1
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Wang M, He J, Dong X, Zhang R. Effect of gradual increase of salt on performance and microbial community during granulation process. J Environ Sci (China) 2025; 147:404-413. [PMID: 39003058 DOI: 10.1016/j.jes.2023.11.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 07/15/2024]
Abstract
Salinity was considered to have effects on the characteristics, performance microbial communities of aerobic granular sludge. This study investigated granulation process with gradual increase of salt under different gradients. Two identical sequencing batch reactors were operated, while the influent of Ra and Rb was subjected to stepwise increments of NaCl concentrations (0-4 g/L and 0-10 g/L). The presence of filamentous bacteria may contribute to granules formed under lower salinity conditions, potentially leading to granules fragmentation. Excellent removal efficiency achieved in both reactors although there was a small accumulation of nitrite in Rb at later stages. The removal efficiencies of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in Ra were 95.31%, 93.70% and 88.66%, while the corresponding removal efficiencies in Rb were 94.19%, 89.79% and 80.74%. Salinity stimulated extracellular polymeric substances (EPS) secretion and enriched EPS producing bacteria to help maintain the integrity and stability of the aerobic granules. Heterotrophic nitrifying bacteria were responsible for NH4+-N and NO2--N oxidation of salinity systems and large number of denitrifying bacteria were detected, which ensure the high removal efficiency of TN in the systems.
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Affiliation(s)
- Mengfei Wang
- School of Environment, Harbin Institute of Technology, Harbin 150090, China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Junguo He
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, China
| | - Xiangke Dong
- National Marine Environmental Monitoring Center, Dalian 116023, China
| | - Ruimiao Zhang
- School of Environment, Harbin Institute of Technology, Harbin 150090, China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, China
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2
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He Q, Tan B, Li M, Su J, Lin B, Wu NP, Shen HN, Chen JJ, Zhang Q. Deciphering the influence of salinity stress on the biological aniline degradation system: Pollutants degradation performance and microbial response. ENVIRONMENTAL RESEARCH 2024; 255:119162. [PMID: 38762003 DOI: 10.1016/j.envres.2024.119162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 04/14/2024] [Accepted: 05/14/2024] [Indexed: 05/20/2024]
Abstract
In order to evaluate the impact of salinity gradients on the aniline biodegradation system, six reactors at salinity concentrations (0%-5%) were established. The results presented the salinity except for 5% imposed negligible effects on aniline degradation performance. Nitrification had prominent resistance to salinity (0%-1.5%) while were significantly restrained when salinity increased. The total nitrogen (TN) removal efficiency of Z4 (1.5%) was 20.5% higher than Z1 (0%) during the stable operation phase. Moreover, high throughput sequencing analysis showed that halophilic bacterium, such as Halomonas, Rhodococcus, remained greater survival advantages in high salinity system. The substantial enrichment of Flavobacterium, Dokdonella, Paracoccus observed in Z4 ensured its excellent nitrogen removal performance. The close cooperation among dominant functional bacteria was strengthened when salt content was below 1.5% while exceeding 1.5% led to the collapse of metabolic capacity through integrating the toxicity of aniline and high osmotic pressure.
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Affiliation(s)
- Qi He
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Bin Tan
- CCCC Second Highway Consultants Co., Ltd., Wuhan, 430056, PR China
| | - Meng Li
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China; Sanya Science and Education Innovation Park, Wuhan University of Technology, Hainan, 572024, PR China
| | - Junhao Su
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Bing Lin
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Nan-Ping Wu
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Hao-Nan Shen
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Jia-Jing Chen
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China; Sanya Science and Education Innovation Park, Wuhan University of Technology, Hainan, 572024, PR China
| | - Qian Zhang
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, PR China.
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3
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Tao Y, Li L, Ning J, Xu W. Culturing partial-denitrification (PD) granules in continuous flow reactor with waste sludge as inoculum: performance, granular sludge characteristics and microbial community. ENVIRONMENTAL TECHNOLOGY 2024; 45:3751-3764. [PMID: 37345969 DOI: 10.1080/09593330.2023.2228993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 06/04/2023] [Indexed: 06/23/2023]
Abstract
Partial denitrification granular sludge (PDGS) can provide long-term stable nitrite for anaerobic ammonia oxidation (anammox). The cultivation of ordinary activated sludge from wastewater treatment plants into PDGS can further promote the application of PD in practical engineering. In this study, the feasibility of fast start-up of PDGS was explored by inoculating waste sludge in up-flow anaerobic sludge blanket (UASB) reactor with synergistic control of nitrogen load rate (NLR, 0.05-0.65 kg N/m3/d) and electron donor starvation (EDS) (240-168 mg L-1), and system performance, particle characteristics and microbial structure were studied. The results showed that PD-UASB started successfully within 48 days, the average nitrite accumulation rate (NTR) and nitrate removal ratio (NRR) reached 79.6% and 82.5% after successful initiation, accompanied by high abundance of PD bacteria (Thauera, Pseudomonas, unclassflied commamonadaceae and Limnobacter) (25.3%). The increase of PD activity, and the difference between nitrate reductase (NAR) and nitrite reductase (NIR) contributed to nitrite production. Besides, the sludge shifted from flocculated (≤0.5 mm, 95.37%) to granulated state (0.5-2 mm, 64.74%), which could be due to the increase of extracellular polymers (EPS) (especially T-EPS) and metabolism of specific microorganisms (Bacteroidota and Chloroflexi, 19.92%). Good sludge granulation promoted the settleability of PD (the SVI5 was 47.248 mL/ g. ss after successful start-up). In summary, good PD sludge granulation process could be achieved in a short time by synergistically controlling NLR and EDS.
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Affiliation(s)
- Youqi Tao
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, People's Republic of China
| | - Linjing Li
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, People's Republic of China
| | - Jianyong Ning
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, People's Republic of China
| | - Wenlai Xu
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, People's Republic of China
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4
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Shi W, Tang Y, Liu Y, Fan J, Huang S, Guo Y, Zhang B, Lens PNL. Deciphering the role of micro/nano-hydroxyapatite in aerobic granular sludge system: Effects on treatment performance and enhancement mechanism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121850. [PMID: 39018842 DOI: 10.1016/j.jenvman.2024.121850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/26/2024] [Accepted: 07/12/2024] [Indexed: 07/19/2024]
Abstract
Hydroxyapatite (HAP), a mineral nucleus identified within aerobic granular sludge (AGS), plays a vital role in enhancing the AGS systems. However, the microscopic mechanism underlying their roles remains largely unexplored. Herein, a systematic investigation was carried out to elucidate the impact and enhanced mechanisms associated with HAP of different sizes, i.e. micro-HAP (mHAP) and nano-HAP (nHAP), on the aerobic granulation, nutrient removal and microbial diversity of AGS. Results showed that the presence of nHAP and mHAP significantly shortened the granulation process to 15 and 20 days, respectively. This might be ascribed to the fact that the large specific surface area of nHAP aggregates was conducive to microbial adhesion, biomass accumulation and sludge granulation. Compared with mHAP, the granules with nHAP showed better settlement performance, mechanical strength and larger diameter. The X-ray diffraction (XRD) and Raman spectrometer analysis confirmed the presence of HAP within the granules, which was found to stimulate the secretion of extracellular polymeric substance, improve the compactness of granule structure and suppress the growth of filamentous bacteria, thereby contributing to a stable AGS system. The presence of HAP, especially nHAP, effectively enriched the functional microorganisms, such as nitrifying and denitrifying bacteria (e.g. Candidatus_Competibacter) and phosphorus accumulating organisms (e.g. Flavobacterium), leading to the improved nutrient removal efficiencies (COD > 96%, TN > 76%, and TP > 74%). Further analysis revealed the up-regulation of functional enzymes (e.g. nitrite oxidoreductase and polyphosphate kinase) involved in nutrient metabolism, underlying the inherent mechanisms for the excellent nutrient removal. This study deepens the understanding of granulation mechanisms from the perspective of mineral cores, and proposes an economically feasible strategy for rapid initiation and stabilization of AGS reactors.
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Affiliation(s)
- Wenxin Shi
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China
| | - Yi Tang
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China
| | - Yi Liu
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China
| | - Jiawei Fan
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China
| | - Shuchang Huang
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China
| | - Yuan Guo
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, China
| | - Bing Zhang
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China.
| | - Piet N L Lens
- UNESCO-IHE, Institute for Water Education, Westvest 7, 2601, DA, Delft, the Netherlands
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Zhou H, Long J, Qin M, Ji X, Wang J, Qian F, Shen Y, Liu W. Successful operation of nitrifying granules at low pH in a continuous-flow reactor: Nitrification performance, granule stability, and microbial community. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121793. [PMID: 38991342 DOI: 10.1016/j.jenvman.2024.121793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 06/29/2024] [Accepted: 07/07/2024] [Indexed: 07/13/2024]
Abstract
Acidic nitrification, as a novel process for treating wastewater without sufficient alkalinity, has received increasing attention over the years. In this study, a continuous-flow reactor with aerobic granular sludge was successful operated at low pH (<6.5) performing high-rate acidic nitrification. Volumetric ammonium oxidation rate of 0.4-1.2 kg/(m3·d) were achieved with the specific biomass activities of 5.8-13.9 mg N/(gVSS·h). Stable partial nitritation with nitrite accumulation efficiency over 85% could be maintained at pH above 6 with the aid of residual ammonium, whereas the nitrite accumulation disappeared when pH was below 6. Interestingly, the granule morphology significantly improved during the acidic operation. The increased secretion of extracellular polymeric substances (especially polysaccharides) suggested a self-protective behavior of microbes in the aerobic granules against acidic stress. 16S rRNA gene sequencing analyses indicated that Candidatus Nitrospira defluvii was always the dominant nitrite-oxidizing bacteria, while the dominant ammonia-oxidizing bacteria shifted from Nitrosomonas europaea to Nitrosomonas mobilis. This study, for the first time, demonstrated the improved stability of aerobic granules under acidic conditions, and also highlighted aerobic granules as a useful solution to achieve high-rate acidic nitrification.
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Affiliation(s)
- Han Zhou
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Jing Long
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Manyu Qin
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Xiaoming Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jianfang Wang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China; National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Feiyue Qian
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China; National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Yaoliang Shen
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China; National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Wenru Liu
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China; National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou, 215009, China.
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6
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Lv YT, Wang Y, Dong J, Miao R, Wang X, Chen X, Wang L. Mechanisms of denitrifying granular sludge disintegration and calcium ion-enhanced re-granulation in acidic wastewater treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121794. [PMID: 38986371 DOI: 10.1016/j.jenvman.2024.121794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 06/01/2024] [Accepted: 07/07/2024] [Indexed: 07/12/2024]
Abstract
Granular sludge is an alternative technology for the direct treatment of acidic nitrate-containing wastewater. Rapid remediation of disintegrated granules is essential to achieve efficient nitrogen removal. In this study, denitrifying granules were inactivated and disintegrated when the influent nitrate-nitrogen concentration was elevated from 240 to 360 mg L-1 in acidic wastewater (pH = 4.1) in a sequencing batch reactor. Tightly bound extracellular polymeric substances (TB-EPS) decreased by 60%, and extracellular protein (PN) was the main component of the reduced EPS. The three-dimensional excitation emission matrices (3D-EEM) results confirmed that the PNs that decreased were mainly tryptophan-like, tyrosine-like, and aromatic. This study further confirmed that the decrease in PN was mainly from the destruction of C=O (amide I) and N-H functional groups. Overloading of nitrogen-inhibited denitrifying activity and the destruction and dissolution of TB-EPS by acidic pH were responsible for granule disintegration, with PNs playing a major role in maintaining granule stability. Based on this, new granules with an average particle size of 454.4 μm were formed after calcium chloride addition; EPS nearly doubled during granule formation with PN as the dominant component, accounting for 64.7-78.4% of the EPS. Atomic force microscopy (AFM) revealed that PN-PN adhesion increased by 1.6-4.9 times in the presence of calcium ions, accelerating the re-granulation of disintegrated particles. This study provides new insights into the disintegration and remediation of granular sludge under acidic conditions.
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Affiliation(s)
- Yong-Tao Lv
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China
| | - Yixin Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China
| | - Jian Dong
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China
| | - Rui Miao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China
| | - Xudong Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China
| | - Xiaolin Chen
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China
| | - Lei Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Membrane Separation of Shaanxi Province, Research Institute of Membrane Separation Technology of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China; Key Laboratory of Environmental Engineering of Shaanxi Province, No. 13 Yanta Road, Xi'an 710055, China.
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7
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Yan A, Chen Y, Li N, Ma T, Qi Y, Xu D. Dewatering performance of aerobic granular sludge under centrifugal with different sludge conditioning agent. Front Microbiol 2024; 15:1386557. [PMID: 38952447 PMCID: PMC11215069 DOI: 10.3389/fmicb.2024.1386557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 04/29/2024] [Indexed: 07/03/2024] Open
Abstract
The aerobic granular sludge(AGS) technology draw scientific researchers attention, and more and more scientific research focuses on it, due to its superior advantages, such as good settling performance, high biological phase, high toxicity resistance and multiple biological effects. With the rapid development of AGS technology, a considerable amount of residual AGS will be produced, and dehydration is the biggest bottleneck of sludge reduction. This study investigated the dewatering process and method of residual AGS cultured by continuous flow experiment. Experiments were conducted using centrifugal dewatering technology with a dosing scheme to analyze the granular sludge dewatering process, and investigate the release process of EPS component in AGS dewatering. Our results implied the specific resistance of AGS has a very low value ((1.82 ± 0.03) × 109 m/kg) and it was not obvious for the conditioning effect of chemical conditioner on AGS dewatering. However, the moisture content can be reduced to 63.5% after dewatering with the presence of inorganic substances. The addition of drinking water treatment plant sludge (Alum sludge) can improve the efficiency of the dewatering of AGS. A possible dewatering process of AGS dewatering was proposed which was divided into two stages: First, a considerable amount of free water in the sludge was quickly removed under the action of gravity without pressure filtration. Second, the bound water release required cooperation between applying centrifugal or pressing force to grind granular cells and separate protein-like substances with the inorganic matter inside the granular sludge. The possible mechanism of AGS dewatering and hypothesis dewatering process are useful to optimize the AGS dewatering process.
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Affiliation(s)
- Ailan Yan
- Nanxun Innovation Institute, Zhejiang University of Water Resources and Electric Power, Hangzhou, China
- College of Water Conservancy and Environmental Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou, China
| | - Yongfei Chen
- Hangzhou Yongzhan Environment Technology Co., Ltd., Hangzhou, China
| | - Ningyu Li
- College of Water Conservancy and Environmental Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou, China
| | - Ting Ma
- China Railway Eryuan Engineering Group East China Exploration & Design Co., Ltd., Hangzhou, China
| | - Yiting Qi
- College of Water Conservancy and Environmental Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou, China
| | - Dong Xu
- College of Water Conservancy and Environmental Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou, China
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8
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Wang J, Li Z, Xiong P, Li Z, Liu H, Zhang Y, Lei Z, Liu X, Lee DJ, Qian X. Reduction of greenhouse gas emissions from closed activated sludge- to aerobic granular sludge-based biosystems via gas circulation. BIORESOURCE TECHNOLOGY 2024; 401:130748. [PMID: 38677387 DOI: 10.1016/j.biortech.2024.130748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Revised: 04/08/2024] [Accepted: 04/25/2024] [Indexed: 04/29/2024]
Abstract
Greenhouse gas (GHG) emissions from biological treatment units are challenging wastewater treatment plants (WWTPs) due to their wide applications and global warming. This study aimed to reduce GHG emissions (especially N2O) using a gas circulation strategy in a closed sequencing-batch reactor when the biological unit varies from activated sludge (AS) to aerobic granular sludge (AGS). Results show that gas circulation lowers pH to 6.3 ± 0.2, facilitating regular granules but elevating total N2O production. From AS to AGS, N2O emission factor increased (0.07-0.86 %) due to decreasing ammonia-oxidizing rates while the emissions of CO2 (0.3 ± 0.1 kg-CO2/kg-chemical oxygen demand) and CH4 remained in the closed biosystem. The gas circulation decreased N2O emission factor by 63 ± 15 % after granulation higher than 44 ± 34 % before granulation, which is implemented by heterotrophic denitrification. This study provides a feasible strategy to enhance heterotrophic N2O elimination in the biological WWTPs.
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Affiliation(s)
- Jixiang Wang
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Zejiao Li
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Pengyu Xiong
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Zhengwen Li
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Hui Liu
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yili Zhang
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Xiang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong; Department of Chemical Engineering & Materials Science, Yuan-Ze University, Chungli 320, Taiwan
| | - Xiaoyong Qian
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China.
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9
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Ni Y, Yang J, Pan J, Wu S, Zou J, Li J. Effects of enhanced biological phosphorus removal on rapid control of sludge bulking and fast formation of aerobic granular sludge. BIORESOURCE TECHNOLOGY 2024; 402:130820. [PMID: 38729583 DOI: 10.1016/j.biortech.2024.130820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/12/2024] [Accepted: 05/07/2024] [Indexed: 05/12/2024]
Abstract
This study investigated the effects of enhanced biological phosphorus removal (EBPR) on rapid sludge bulking control and fast aerobic granular sludge (AGS) formation by adding 20 % of EBPR activated sludge to the bulking activated sludge (BAS) reactor. The results indicate that activating EBPR activity swiftly improved BAS settleability within 16 days, thus resolving sludge bulking issues. Subsequently, a settling time-based selection was employed, resulting in the BAS granulation within another 16 days. The rapid achievement of EBPR activity improved the BAS settleability and facilitated the formation of sludge aggregates, thereby expediting BAS granulation. Inhibition of filamentous bacteria and enrichment of slow-growing organisms contributed to both sludge bulking control and aerobic granulation. Furthermore, the increase in proteins/polysaccharides ratio facilitated the granulation process. Additionally, total nitrogen removal increased from 59.4 % to 71.7 % because of the mature AGS formation. This study provided an approach to simultaneously control sludge bulking and promote aerobic granulation.
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Affiliation(s)
- Yongjiong Ni
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jiaqi Yang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jiyang Pan
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Shuyun Wu
- College of Geomatics and Municipal Engineering, Zhejiang University of Water Resources and Electric Power, Hangzhou 310018, China
| | - Jinte Zou
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; Shaoxing Research Institute, Zhejiang University of Technology, Shaoxing 312000, China.
| | - Jun Li
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
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10
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Cicekalan B, Berenji NR, Aras MF, Guven H, Koyuncu I, Ersahin ME, Ozgun H. Impact of food waste addition in energy efficient municipal wastewater treatment by aerobic granular sludge process. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:29304-29320. [PMID: 38570432 PMCID: PMC11058935 DOI: 10.1007/s11356-024-32997-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 03/15/2024] [Indexed: 04/05/2024]
Abstract
Recently, one of the main purposes of wastewater treatment plants is to achieve a neutral or positive energy balance while meeting the discharge criteria. Aerobic granular sludge (AGS) technology is a promising technology that has low energy and footprint requirements as well as high treatment performance. The effect of co-treatment of municipal wastewater and food waste (FW) on the treatment performance, granule morphology, and settling behavior of the granules was investigated in the study. A biochemical methane potential (BMP) test was also performed to assess the methane potential of mono- and co-digestion of the excess sludge from the AGS process. The addition of FW into wastewater enhanced the nutrient treatment efficiency in the AGS process. BMP of the excess sludge from the AGS process fed with the mixture of wastewater and FW (195 ± 17 mL CH4/g VS) was slightly higher than BMP of excess sludge from the AGS process fed with solely wastewater (173 ± 16 mL CH4/g VS). The highest methane yield was observed for co-digestion of excess sludge from the AGS process and FW, which was 312 ± 8 mL CH4/g VS. Integration of FW as a co-substrate in the AGS process would potentially enhance energy recovery and the quality of effluent in municipal wastewater treatment.
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Affiliation(s)
- Busra Cicekalan
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey.
| | - Nastaran Rahimzadeh Berenji
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Muhammed Furkan Aras
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Huseyin Guven
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Ismail Koyuncu
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- National Research Center On Membrane Technologies, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Mustafa Evren Ersahin
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- National Research Center On Membrane Technologies, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Hale Ozgun
- Civil Engineering Faculty, Department of Environmental Engineering, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- National Research Center On Membrane Technologies, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
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11
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Joel EO, Akinlabi OC, Olaposi AV, Olowomofe TO, Adekanmbi AO. High carriage of plasmid-mediated quinolone resistance (PMQR) genes by ESBL-producing and fluoroquinolone-resistant Escherichia coli recovered from animal waste dumps. Mol Biol Rep 2024; 51:424. [PMID: 38491992 DOI: 10.1007/s11033-024-09228-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 01/08/2024] [Indexed: 03/18/2024]
Abstract
BACKGROUND There has been a rise in the consumption of fluoroquinolones in human and veterinary medicine recently. This has contributed to the rising incidence of quinolone resistance in bacteria. This study aimed at the determination of the antibiotic resistance profile of ESBL-producing and fluoroquinolone-resistant E. coli (FQEC) isolated from animal waste obtained from the waste dumps of an agricultural farm and their carriage of genes encoding PMQR. METHODS AND RESULTS Isolation of ESBL-producing E. coli from animal waste samples was done on CHROMagar ESBL, while presumptive isolates were purified, and identified via the detection of uidA gene. Susceptibility to a panel of ten antibiotics was done using the disc diffusion method, and detection of PMQR genes (qnrA, qnrB, qnrS, aac(6')-lb-cr, qepA and oqxAB) was done using monoplex and duplex PCR. Twenty-five ESBL-producing and FQEC were obtained from the cattle (6), piggery (7) and poultry (12) waste dumps of the farm. There was 100% resistance to cefpodoxime, cefotaxime, enrofloxacin, trimethoprim-sulfamethoxazole and penicillin by the isolates. The resistance to the other antibiotics was streptomycin (48%), ceftazidime (24%), while no isolate resisted amoxicillin-clavulanate and imipenem. The frequencies of PMQR genes detected were; qnrA (96%), oqxAB (96%), qnrB (92%), while qnrS was detected in 88% (22) of the isolates. Aminoglycoside acetyltransferase (aac(6')-lb-cr) and quinolone efflux pump (qepA) were each detected in 20 (80%) of the isolates. CONCLUSIONS This study showed that animal wastes disposed indiscriminately into dumps could be a budding 'hotspot' for multidrug resistant, ESBL-producing and fluoroquinolone-resistant E. coli carrying multiple genes encoding resistance to fluoroquinolone antibiotics.
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Affiliation(s)
- Elizabeth Omokoshi Joel
- Department of Animal Science, Faculty of Agriculture, University of Ibadan, Ibadan, Nigeria
- Molecular Biology and Biotechnology Laboratory, Department of Microbiology, University of Ibadan, Ibadan, Nigeria
| | - Olabisi Comfort Akinlabi
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan, Ibadan, Nigeria.
| | - Adedolapo Victoria Olaposi
- Environmental Microbiology and Biotechnology Laboratory, Department of Microbiology, University of Ibadan, Ibadan, Nigeria
- Molecular Biology and Biotechnology Laboratory, Department of Microbiology, University of Ibadan, Ibadan, Nigeria
| | | | - Abimbola Olumide Adekanmbi
- Environmental Microbiology and Biotechnology Laboratory, Department of Microbiology, University of Ibadan, Ibadan, Nigeria.
- Molecular Biology and Biotechnology Laboratory, Department of Microbiology, University of Ibadan, Ibadan, Nigeria.
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12
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Mills S, Trego AC, Prevedello M, De Vrieze J, O’Flaherty V, Lens PN, Collins G. Unifying concepts in methanogenic, aerobic, and anammox sludge granulation. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 17:100310. [PMID: 37705860 PMCID: PMC10495608 DOI: 10.1016/j.ese.2023.100310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 06/17/2023] [Accepted: 08/05/2023] [Indexed: 09/15/2023]
Abstract
The retention of dense and well-functioning microbial biomass is crucial for effective pollutant removal in several biological wastewater treatment technologies. High solids retention is often achieved through aggregation of microbial communities into dense, spherical aggregates known as granules, which were initially discovered in the 1980s. These granules have since been widely applied in upflow anaerobic digesters for waste-to-energy conversions. Furthermore, granular biomass has been applied in aerobic wastewater treatment and anaerobic ammonium oxidation (anammox) technologies. The mechanisms underpinning the formation of methanogenic, aerobic, and anammox granules are the subject of ongoing research. Although each granule type has been extensively studied in isolation, there has been a lack of comparative studies among these granulation processes. It is likely that there are some unifying concepts that are shared by all three sludge types. Identifying these unifying concepts could allow a unified theory of granulation to be formed. Here, we review the granulation mechanisms of methanogenic, aerobic, and anammox granular sludge, highlighting several common concepts, such as the role of extracellular polymeric substances, cations, and operational parameters like upflow velocity and shear force. We have then identified some unique features of each granule type, such as different internal structures, microbial compositions, and quorum sensing systems. Finally, we propose that future research should prioritize aspects of microbial ecology, such as community assembly or interspecies interactions in individual granules during their formation and growth.
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Affiliation(s)
- Simon Mills
- Microbial Communities Laboratory, School of Biological and Chemical Sciences, National University of Ireland Galway, University Road, Galway, H91 TK33, Ireland
| | - Anna Christine Trego
- Microbial Ecology Laboratory School of Biological and Chemical Sciences, University of Galway, University Road, Galway, H91 TK33, Ireland
| | - Marco Prevedello
- Microbial Communities Laboratory, School of Biological and Chemical Sciences, National University of Ireland Galway, University Road, Galway, H91 TK33, Ireland
| | - Jo De Vrieze
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000, Gent, Belgium
| | - Vincent O’Flaherty
- Microbial Ecology Laboratory School of Biological and Chemical Sciences, University of Galway, University Road, Galway, H91 TK33, Ireland
| | - Piet N.L. Lens
- University of Galway, University Road, Galway, H91 TK33, Ireland
| | - Gavin Collins
- Microbial Communities Laboratory, School of Biological and Chemical Sciences, National University of Ireland Galway, University Road, Galway, H91 TK33, Ireland
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13
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Zhang X, Zhao B, An Q, Zhang P. The influence of different nitrate concentrations on aerobic sludge granulation and the role of extracellular polymeric substances. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 348:119226. [PMID: 37820429 DOI: 10.1016/j.jenvman.2023.119226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 09/13/2023] [Accepted: 10/02/2023] [Indexed: 10/13/2023]
Abstract
This study investigated the influence of nitrate on aerobic granular sludge (AGS) granulation. The introduction of nitrate at 5, 15 and 20 mg L-1 promoted AGS granulation, and the promoting effect was positively correlated with nitrate concentrations. Meanwhile, exogenous nitrate significantly increased denitrification rate in the AGS system. However, granular disintegration appeared at a long-term addition of nitrate. An in-deep analysis showed that nitrate stimulated the secretion of extracellular polymeric substances (EPS), especially the content of proteins, which might be the main reason for the AGS granulation. However, the rapid and excessive increase in EPS might cause granular disintegration, as excessive EPS blocked the transmission of substrates, leading to the increase of dead cells in the granules. Besides, nitrate also altered the hydrophobicity of EPS and the content of α-helix, 3-turned helix and polymeric chain that favored aggregation, which also affected AGS granulation. From the microbial community level, nitrate induced the enrichment of denitrifying bacteria, including those that also functioned as EPS producers, such as Micropruina and Flavobacterium, resulting in the rapid increase of functional enzymes associated with amino acid synthesis, thereby promoting the secretion of proteins in EPS. Conversely, disintegration caused by mass transfer blockage might lead to the loss of EPS producing bacteria and subsequent decrease in EPS content, further accelerating granular disintegration.
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Affiliation(s)
- Xinyi Zhang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Bin Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China.
| | - Qiang An
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Peng Zhang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
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14
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De Vleeschauwer F, Dries J. Full dynamic control of dairy wastewater treatment by aerobic granular sludge using electric conductivity and oxygen uptake rate. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:2707-2718. [PMID: 38096063 PMCID: wst_2023_361 DOI: 10.2166/wst.2023.361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
The objective of the current study was to determine the applicability of a sensor-based dynamic control strategy for the treatment of real variable dairy wastewater by aerobic granular sludge (AGS) performing enhanced biological phosphorus removal (EBPR). Two parallel sequencing batch reactors (SBRs) were set up that used only an anaerobic feast/aerobic famine microbial selection strategy to successfully obtain sludge granulation. SBR-STA used a fixed cycle length, while the duration of the reaction steps in SBR-DYN was variable. The control strategy was based solely on (derived) signals from low-cost and common sensors. The profile of the electric conductivity during the anaerobic reaction step was related to the microbial release of phosphate (PO4-P) and the associated uptake of dissolved organic carbon (DOC) by polyphosphate-accumulating organisms (PAOs). Control of the aerobic reaction step was based on the oxygen uptake rate (OUR). This resulted in a dynamic reactor operation with significant efficiency gains, such as 32% shorter cycle times and 42% higher sludge loading rates without impairing the effluent quality. These results extend the existing potential of indirect control strategies to full biological nutrient removal processes, which may be of great assistance to the operators and designers of industrial installations.
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Affiliation(s)
- Flinn De Vleeschauwer
- Research Group BioWAVE, Biochemical Wastewater Valorisation and Engineering, Faculty of Applied Engineering, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium E-mail:
| | - Jan Dries
- Research Group BioWAVE, Biochemical Wastewater Valorisation and Engineering, Faculty of Applied Engineering, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium
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15
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Wang G, Huang X, Wang S, Yang F, Sun S, Yan P, Chen Y, Fang F, Guo J. Effect of food-to-microorganisms ratio on aerobic granular sludge settleability: Microbial community, potential roles and sequential responses of extracellular proteins and polysaccharides. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118814. [PMID: 37591089 DOI: 10.1016/j.jenvman.2023.118814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/18/2023] [Accepted: 08/12/2023] [Indexed: 08/19/2023]
Abstract
The food-to-microorganism ratio (F/M) is an important parameter in wastewater biotreatment that significantly affects the granulation and settleability of aerobic granular sludge (AGS). Hence, understanding the long-term effects and internal mechanisms of F/M on AGS settling performance is essential. This study investigated the relationship between F/M and the sludge volume index (SVI) within a range of 0.23-2.50 kgCOD/(kgMLVSS·d). Thiothrix and Candidatus_Competibacter were identified as two dominant bacterial genera influencing AGS settling performance. With F/M increased from 0.27 kgCOD/(kgMLVSS·d) to 1.53 kgCOD/(kgMLVSS·d), the abundance of Thiothrix significantly increased from 0.20% to 27.02%, and the hydrophobicity of extracellular proteins (PN) decreased, which collectively reduced AGS settling performance. However, under high-F/M conditions, the gel-like polysaccharides (PS) effectively retained the granular biomass by binding to the highly abundant Thiothrix (53.65%). The progressive increment in biomass led to a concomitant reduction in F/M, resulting in the recovery of AGS settleability. In addition, two-dimensional correlation infrared spectroscopy analysis revealed the preferential responses of PN and PS to the increase and decrease of F/M, and the content and characteristics of PN and PS played important roles in granular settling. The study provides insight into the microbial composition and the potential role of extracellular polymer substances in the AGS sedimentation behavior, offering valuable theoretical support for stable AGS operation.
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Affiliation(s)
- Gonglei Wang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Xiaoxiao Huang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Shuai Wang
- College of Environment Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Fan Yang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Shiting Sun
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Peng Yan
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Youpeng Chen
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Fang Fang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
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16
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He Q, Yan X, Wang H, Ji Y, Li J, Liu L, Bi P, Xu P, Xu B, Ma J. Towards a better understanding of the anaerobic/oxic/anoxic-aerobic granular sludge process (AOA-AGS) for simultaneous low-strength wastewater treatment and in situ sludge reduction from ambient to winter temperatures. ENVIRONMENTAL RESEARCH 2023; 236:116822. [PMID: 37541415 DOI: 10.1016/j.envres.2023.116822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/06/2023]
Abstract
The new anaerobic/oxic/anoxic-aerobic granular sludge (AOA-AGS) merits the advantages of effective carbon utilization and low-carbon treatment. However, low temperature poses stressing concerns and the resisting mechanism remains much unknown. Herein, an AOA-AGS process was configured for simultaneous nitrification, denitrification and phosphorus removal (SNDPR) with low-strength wastewater from ambient (>15 °C) to winter temperatures (<15 °C). Results showed that simultaneously advanced nutrients removal, and dramatic in situ sludge reduction (Yobs of 0.093 g MLSS/g COD) were gained regardless of seasonally decreasing temperatures. Winter temperatures even amplified Candidatus Competibacter predominating from 20.11% to 34.74%, which laid the core basis for endogenous denitrification, sludge minimization and temperature resistance. A removal model was thus proposed given the observed functional groups, and doubts were also raised for future investigations. This study would aid a better understanding on the microbial ecology and engineering aspects of the new AOA-AGS process treating low-strength wastewater at low temperatures.
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Affiliation(s)
- Qiulai He
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Xiaohui Yan
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan, 430082, China
| | - Yaning Ji
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Jinfeng Li
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Liang Liu
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Peng Bi
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Peng Xu
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Baokun Xu
- Agricultural Water Conservancy Department, Changjiang River Scientific Research Institute, Wuhan, 430010, China
| | - Jingwei Ma
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China.
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17
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Nuid M, Aris A, Krishnen R, Chelliapan S, Muda K. Pineapple wastewater as co-substrate in treating real alkaline, non-biodegradable textile wastewater using biogranulation technology. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118501. [PMID: 37418913 DOI: 10.1016/j.jenvman.2023.118501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 05/25/2023] [Accepted: 06/22/2023] [Indexed: 07/09/2023]
Abstract
This study was to develop biogranules using a sequencing batch reactor (SBR) and to evaluate the effect of pineapple wastewater (PW) as a co-substrate for treating real textile wastewater (RTW). The biogranular system cycle was 24 h (2 stages of phase), with an anaerobic phase (17.8 h) followed by an aerobic phase (5.8 h) for every stage of the phase. The concentration of pineapple wastewater was the main factor studied in influencing COD and color removal efficiency. Pineapple wastewater with different concentrations (7, 5, 4, 3, and 0% v/v) makes a total volume of 3 L and causes the OLRs to vary from 2.90 to 0.23 kg COD/m3day. The system achieved 55% of average color removal and 88% of average COD removal at 7%v/v PW concentration during treatment. With the addition of PW, the removal increased significantly. The experiment on the treatment of RTW without any added nutrients proved the importance of co-substrate in dye degradation.
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Affiliation(s)
- Maria Nuid
- Centre for Environmental Sustainability and Water Security, Research Institute for Sustainable Environment, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Bahru, Malaysia
| | - Azmi Aris
- Centre for Environmental Sustainability and Water Security, Research Institute for Sustainable Environment, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Bahru, Malaysia; Department of Water and Environmental Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Bahru, Malaysia.
| | - Ranjeni Krishnen
- Bactiguard South East Asia SDN. BHD., 308b, Jalan Perindustrian Bukit Minyak 18, Penang Science Park, 14100 Penang, Malaysia
| | - Shreeshivadasan Chelliapan
- Centre for Environmental Sustainability and Water Security, Research Institute for Sustainable Environment, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Bahru, Malaysia; Department of Engineering and Technology, Razak Faculty of Technology and Informatics, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia
| | - Khalida Muda
- Department of Water and Environmental Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Bahru, Malaysia
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18
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Xu J, Gao Y, Bi X, Li L, Xiang W, Liu S. Positive effects of lignocellulose on the formation and stability of aerobic granular sludge. Front Microbiol 2023; 14:1254152. [PMID: 37670989 PMCID: PMC10475587 DOI: 10.3389/fmicb.2023.1254152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 07/31/2023] [Indexed: 09/07/2023] Open
Abstract
Introduction Lignocellulose is one of the major components of particulate organic matter in sewage, which has a significant influence on biological wastewater treatment process. However, the effect of lignocellulose on aerobic granular sludge (AGS) system is still unknown. Methods In this study, two reactors were operated over 5 months to investigate the effect of lignocellulose on granulation process, structure stability and pollutants removal of AGS. Results and discussion The results indicated that lignocellulose not only promoted the secretion of tightly bound polysaccharide in extracellular polymeric substances, but also acted as skeletons within granules, thereby facilitating AGS formation, and enhancing structural strength. Lignocellulose imposed little effect on the removal efficiency of pollutants, with more than 95, 99, and 92% of COD, NH4+-N, and PO43--P were removed in both reactors. However, it did exhibit a noticeable influence on pollutants conversion processes. This might be due to that the presence of lignocellulose promoted the enrichment of functional microorganisms, including Candidatus_Accumulibacter, Candidatus_Competibacter, Nitrosomonas, and Nitrospira, etc. These findings might provide valuable insights into the control strategy of lignocellulose in practical AGS systems.
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Affiliation(s)
- Jie Xu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Yuan Gao
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Xuejun Bi
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Lin Li
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Wenjuan Xiang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Shichang Liu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
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19
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Liu S, Zhou M, Daigger GT, Huang J, Song G. Granule formation mechanism, key influencing factors, and resource recycling in aerobic granular sludge (AGS) wastewater treatment: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 338:117771. [PMID: 37004484 DOI: 10.1016/j.jenvman.2023.117771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 03/14/2023] [Accepted: 03/18/2023] [Indexed: 06/19/2023]
Abstract
The high-efficiency and additionally economic benefits generated from aerobic granular sludge (AGS) wastewater treatment have led to its increasing popularity among academics and industrial players. The AGS process can recycle high value-added biomaterials including extracellular polymeric substances (EPS), sodium alginate-like external polymer (ALE), polyhydroxyfatty acid (PHA), and phosphorus (P), etc., which can serve various fields including agriculture, construction, and chemical while removing pollutants from wastewaters. The effects of various key operation parameters on formation and structural stability of AGS are comprehensively summarized. The degradable metabolism of typical pollutants and corresponding microbial diversity and succession in the AGS wastewater treatment system are also discussed, especially with a focus on emerging contaminants removal. In addition, recent attempts for potentially effective production of high value-added biomaterials from AGS are proposed, particularly concerning improving the yield, quality, and application of these biomaterials. This review aims to provide a reference for in-depth research on the AGS process, suggesting a new alternative for wastewater treatment recycling.
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Affiliation(s)
- Shuli Liu
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China; Zhongzhou Water Holding Co., Ltd., Zhengzhou, 450046, China; Civil and Environmental Engineering, University of Michigan, 2350 Hayward St, G.G. Brown Building, Ann Arbor, MI, 48109, USA.
| | - Miao Zhou
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China.
| | - Glen T Daigger
- Civil and Environmental Engineering, University of Michigan, 2350 Hayward St, G.G. Brown Building, Ann Arbor, MI, 48109, USA.
| | - Jianping Huang
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China.
| | - Gangfu Song
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China; Zhongzhou Water Holding Co., Ltd., Zhengzhou, 450046, China.
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20
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Cheng L, Wei M, Hu Q, Li B, Li B, Wang W, Abudi ZN, Hu Z. Aerobic granular sludge formation and stability in enhanced biological phosphorus removal system under antibiotics pressure: Performance, granulation mechanism, and microbial successions. JOURNAL OF HAZARDOUS MATERIALS 2023; 454:131472. [PMID: 37099906 DOI: 10.1016/j.jhazmat.2023.131472] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 04/04/2023] [Accepted: 04/21/2023] [Indexed: 05/19/2023]
Abstract
Wastewater containing antibiotics can pose a significant threat to biological wastewater treatment processes. This study investigated the establishment and stable operation of enhanced biological phosphorus removal (EBPR) by aerobic granular sludge (AGS) under mixed stress conditions induced by tetracycline (TC), sulfamethoxazole (SMX), ofloxacin (OFL), and roxithromycin (ROX). The results show that the AGS system was efficient in removing TP (98.0%), COD (96.1%), and NH4+-N (99.6%). The average removal efficiencies of the four antibiotics were 79.17% (TC), 70.86% (SMX), 25.73% (OFL), and 88.93% (ROX), respectively. The microorganisms in the AGS system secreted more polysaccharides, which contributed to the reactor's tolerance to antibiotics and facilitated granulation by enhancing the production of protein, particularly loosely bound protein. Illumina MiSeq sequencing revealed that putative phosphate accumulating organisms (PAOs)-related genera (Pseudomonas and Flavobacterium) were enormously beneficial to the mature AGS for TP removal. Based on the analysis of extracellular polymeric substances, extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, and microbial community, a three-stage granulation mechanism was proposed including adaption to the stress environment, formation of early aggregates and maturation of PAOs enriched microbial granules. Overall, the study demonstrated the stability of EBPR-AGS under mixed antibiotics pressure, providing insight into the granulation mechanism and the potential use of AGS for wastewater treatment containing antibiotics.
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Affiliation(s)
- Long Cheng
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Mingyu Wei
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Qixing Hu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Bingtang Li
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Bo Li
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Wenjia Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zaidun Naji Abudi
- Environmental Engineering Department, College of Engineering, Mustansiriyah University, Baghdad 999048, Iraq
| | - Zhiquan Hu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
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21
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Yue J, Han X, Jin Y, Yu J. Potential of direct granulation and organic loading rate tolerance of aerobic granular sludge in ultra-hypersaline environment. ENVIRONMENTAL RESEARCH 2023; 228:115831. [PMID: 37024036 DOI: 10.1016/j.envres.2023.115831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/27/2023] [Accepted: 04/01/2023] [Indexed: 05/16/2023]
Abstract
Salt-tolerant aerobic granular sludge (SAGS) technology has shown potentials in the treatment of ultra-hypersaline high-strength organic wastewater. However, the long granulation period and salt-tolerance acclimation period are still bottlenecks that hinder SAGS applications. In this study, "one-step" development strategy was used to try to directly cultivate SAGS under 9% salinity, and the fastest cultivation process was obtained under such high salinity compared to the previous papers with the inoculum of municipal activated sludge without bioaugmentation. Briefly, the inoculated municipal activated sludge was almost discharged on Day 1-10, then fungal pellets appeared and it gradually transitioned to mature SAGS (particle size of ∼4156 μm and SVI30 of 57.8 mL/g) from Day 11 to Day 47 without fragmentation. Metagenomic revealed that fungus Fusarium played key roles in the transition process probably because it functioned as structural backbone. RRNPP and AHL-mediated systems might be the main QS regulation systems of bacteria. TOC and NH4+-N removal efficiencies maintained at ∼93.9% (after Day 11) and ∼68.5% (after Day 33), respectively. Subsequently, the influent organic loading rate (OLR) was stepwise increased from 1.8 to 11.7 kg COD/m3·d. It was found that SAGS could maintain intact structure and low SVI30 (< 55 mL/g) under 9% salinity and the OLR of 1.8-9.9 kg COD/m3·d with adjustment of air velocity. TOC and NH4+-N (TN) removal efficiencies could maintain at ∼95.4% (below OLR of 8.1 kg COD/m3·d) and ∼84.1% (below nitrogen loading rate of 0.40 kg N/m3·d) in ultra-hypersaline environment. Halomonas dominated the SAGS under 9% salinity and varied OLR. This study confirmed the feasibility of direct aerobic granulation in ultra-hypersaline environment and verified the upper OLR boundary of SAGS in ultra-hypersaline high-strength organic wastewater treatment.
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Affiliation(s)
- Jingxue Yue
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; National Engineering Research Center for Integrated Utilization of Salt Lake Resources, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Xushen Han
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; National Engineering Research Center for Integrated Utilization of Salt Lake Resources, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
| | - Yan Jin
- National Engineering Research Center for Integrated Utilization of Salt Lake Resources, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Jianguo Yu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; National Engineering Research Center for Integrated Utilization of Salt Lake Resources, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
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22
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Xie Z, Zhang N, Yang G, Xu Q, Wang D, Tang L, Xia J, Li P, Li X. Environmentally relevant level of perfluorooctanoic acid affect the formation of aerobic granular sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 336:117659. [PMID: 36893544 DOI: 10.1016/j.jenvman.2023.117659] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 02/10/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
The growing increasing occurrence of perfluorooctanoic acid (PFOA) in wastewater has raised concerns about its potential impact on the environment. Nevertheless, the impact of PFOA at environmentally relevant level on the formation of aerobic granular sludge (AGS) is still a 'black box'. This study thus aims to fill this gap by comprehensive investigation of sludge properties, reactor performance and microbial community during the formation of AGS. It was found that 0.1 mg/L PFOA delayed the formation of AGS, causing relatively lower proportion of large size AGS at the end of operation process. Interestingly, the microorganisms contribute to the reactor's tolerance to PFOA by secreting more extracellular polymeric substances (EPS) to slow or block the entry of toxic substances into the cells. During the granule maturation period, the reactor nutrient removal especially chemical oxygen demand (COD) and total nitrogen (TN) were affected by PFOA, decreasing the corresponding removal efficiencies to ∼81.2% and ∼69.8%, respectively. Microbial analysis further revealed that PFOA decreased the abundances of Plasticicumulans, Thauera, Flavobacterium and Cytophagaceae_uncultured, but it has promoted Zoogloea and Betaproteobacteria_unclassified growth, which maintained the structures and functions of AGS. The above results revealed that the intrinsic mechanism of PFOA on the macroscopic representation of sludge granulation process was revealed, and it is expected to provide theoretical insights and practical support for direct adoption of municipal or industrial wastewater containing perfluorinated compounds to cultivate AGS.
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Affiliation(s)
- Zhouyun Xie
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China
| | - Ni Zhang
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China; College of Environmental Science and Engineering and Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha, 410082, PR China
| | - Guojing Yang
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China; College of Environmental Science and Engineering and Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha, 410082, PR China.
| | - Qiuxiang Xu
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China; College of Environmental Science and Engineering and Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha, 410082, PR China
| | - Dongbo Wang
- College of Environmental Science and Engineering and Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha, 410082, PR China.
| | - Li Tang
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China
| | - Jingfen Xia
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China
| | - Ping Li
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, 315100, PR China
| | - Xiaoming Li
- College of Environmental Science and Engineering and Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha, 410082, PR China
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23
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Wang S, Wang G, Yan P, Chen Y, Fang F, Guo J. Non-filamentous sludge bulking induced by exopolysaccharide variation in structure and properties during aerobic granulation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162786. [PMID: 36907402 DOI: 10.1016/j.scitotenv.2023.162786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 02/13/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
The forming mechanism of non-filamentous sludge bulking during aerobic granulation were investigated basing on three feeding strategies (R1 direct aeration after fast feeding, R2 anaerobic stirring after fast feeding and R3 anaerobic plug-flow slow feeding). Results showed that strong selection stress (shortening settling time) led to a sharp flocs washout and the subsequent increase of food to microorganisms (F/M) in R1 and R3 reactors, but not found in R2 due to the different strategies of feeding modes. With the increase of F/M, zeta potential and hydrophobicity of sludge surfaces significantly decreased and thus leading to an enhanced repulsive force and energy barriers for sludge aggregation. Particularly, when F/M exceeded 1.2 kgCOD/(kgMLSS·d), non-filamentous sludge bulking was ultimately triggered in R1 and R3. Further analysis showed that massive extracellular exopolysaccharide (PS) accumulated on the surfaces of non-filamentous bulking sludge due to the increased abundance of the microorganisms related to PS secretion during sludge bulking. In addition, significantly increased intracellular second messenger (c-di-GMP), a key substance regulating PS biosynthesis, was confirmed via its concentration determination as well as microbial function prediction analysis, which played a critical role in sludge bulking. Combing with the systematic detection from surface plasmon resonance system, rheometer and size-exclusion chromatography-multiangle laser light detection-refractive index system, higher molecular weight, compact conformation, higher viscosity and higher hydrophilicity was determined in sludge bulking PS relative to PS extracted from non-filamentous bulking sludge. Clearly, the changes of PS (content, structures and properties) driven by c-di-GMP are the dominant mechanism for the formation of non-filamentous sludge bulking during aerobic granulation. This work could provide theoretical support for successful start-up and application of aerobic granular sludge technology.
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Affiliation(s)
- Shuai Wang
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China; College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Gonglei Wang
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Peng Yan
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Youpeng Chen
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Fang Fang
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
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24
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Zhang B, Tang H, Huang D, Liu C, Shi W, Shen Y. Effect of superficial gas velocity on membrane fouling behavior and evolution during municipal wastewater treatment. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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25
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Ji Y, Liu J, Wang C, Zhang F, Xu X, Zhu L. Stability improvement of aerobic granular sludge (AGS) based on Gibbs free energy change (∆G) of sludge-water interface: Abstract2. Materials and Methods. WATER RESEARCH 2023; 240:120059. [PMID: 37216787 DOI: 10.1016/j.watres.2023.120059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/20/2022] [Accepted: 05/08/2023] [Indexed: 05/24/2023]
Affiliation(s)
- Yatong Ji
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Jieyi Liu
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Chen Wang
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Fan Zhang
- Environmental Protection Bureau of Changxing County, Huzhou 313100, China
| | - Xiangyang Xu
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou 310058, China
| | - Liang Zhu
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou 310058, China.
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26
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Hang Z, Tong P, Zhao P, He Z, Shao L, Jia Y, Wang XC, Li Z. Hierarchical stringent response behaviors of activated sludge system to stressed conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 870:161832. [PMID: 36716870 DOI: 10.1016/j.scitotenv.2023.161832] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 06/18/2023]
Abstract
The stringent response of activated sludge systems to either stressed or harmful environments is important for the stable operation of activated sludge, which is examined by taking copper ion (Cu2+) as a stress model in this study. When weak stress was employed (Cu2+ ≤ 2.5 mg/L), the N-acyl-homoserine lactones (AHLs) of C6-, C8-, and C10-HSL increased by 30 %, 13 %, and 127 %, respectively, while the redox sensor green (RSG) intensity decreased by 28 %. Encountering the increased stress (2.5 mg/L < Cu2+ ≤ 5 mg/L), bacteria concentration in the supernatant increased by 87 %. However, the respiration rates of autotrophic and heterotrophic bacteria (SOURa and SOURh) and adenosine triphosphate decreased by 52 %, 18 %, and 27 %, respectively, and the flocs disintegrated with a diameter decreasing from 57 to 51 μm. When the stress became more serious (Cu2+ > 5 mg/L), the respiration rates continued to decline, but the quasi-endogenous respiration ratio (Rq/t) increased from 31 % to 47 %. Negligible changes occurred in the endogenous respiration rate (SOURe), adenosine diphosphate, and adenosine monophosphate. Based on these results, a hierarchical stringent response model of the activated sludge system to stressed conditions was proposed, and these responses were evaluated by respirogram. The initial response to weak stress was related to the most sensitive signals of quorum sensing and RSG intensity, well described by the quasi-endogenous respiration rate. The adaptive response to increased stress was the proactive migrations of low- and high-nucleic-acid bacteria to the supernatant, causing the looseness and even disintegration of sludge flocs, well described by SOURa, SOURh, and Rq/t. The lethal response to lethal stress was related to endogenous metabolic processes, well described by SOURe. This work provides new insights into understanding the stringent response of activated sludge systems to some stressed conditions. It helps to regulate the stability of activated sludge systems with respirogram technology.
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Affiliation(s)
- Zhenyu Hang
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Peipei Tong
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Pian Zhao
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhangwei He
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Linjun Shao
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yanru Jia
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiaochang C Wang
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhihua Li
- Key Laboratory of Northwest Water Resource, Environment, and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Xi'an Key Laboratory of Intelligent Equipment Technology in Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
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27
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Biliani SE, Manariotis ID. Wastewater treatment by high density algal flocs for nutrient removal and biomass production. JOURNAL OF APPLIED PHYCOLOGY 2023; 35:1237-1250. [PMID: 37249918 PMCID: PMC9990567 DOI: 10.1007/s10811-023-02931-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 02/15/2023] [Accepted: 02/15/2023] [Indexed: 05/31/2023]
Abstract
The present work investigated the efficiency of algal flocs biomass for the treatment of primary and secondary effluent in static and mixing conditions under different hydraulic retention time (HRT). Primary effluent fed cultures created a high-density biomass of 2.8 and 3.8 g L-1 under static and mixing conditions, respectively. Secondary effluent was more effective in order to create even higher density biomass of 7.8 and 6 g L-1 under static and mixing conditions, respectively. The algal floc biomass developed was quite effective for organic matter and nutrient removal. Primary effluent fed cultures seemed to be more efficient for chemical oxygen demand (COD) and ammonia nitrogen removal, while secondary effluent fed cultures for nitrates removal. At an HRT of 8 days using primary effluent, the removal of COD, ammonia nitrogen and total phosphorus was 86.2, 100 and 97.4%, respectively. The cultures fed with secondary effluent, even at low HRT of 1.2 days, achieved removals of 88.4, 77.5, 100 and 98.6% for COD, nitrates, ammonia, and total phosphorus, respectively. Supplementary Information The online version contains supplementary material available at 10.1007/s10811-023-02931-2.
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Affiliation(s)
- Styliani E. Biliani
- Environmental Engineering Laboratory, Department of Civil Engineering, University of Patras, 26504 Rio, Greece
| | - Ioannis D. Manariotis
- Environmental Engineering Laboratory, Department of Civil Engineering, University of Patras, 26504 Rio, Greece
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28
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Du R, Liu Q, Peng Y, Cao S. Potential causes of partial-denitrification (PD) granular sludge breakdown under high nitrate loading rates. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160749. [PMID: 36496026 DOI: 10.1016/j.scitotenv.2022.160749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/28/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
The granule instability has been frequently reported during the operation of high loading rates. While, there no research was performed on the recently developed anoxic partial-denitrification (PD) granules, a novel pathway in producing nitrite from nitrate for anammox process. Herein, this work, for the first time, investigated the influence of nitrate loading rates on the instability of PD granules and identified the key causes. Two lab-scale sequencing batch reactors (SBRs) were operated with nitrate loading rates (NLR) increased from 0.48 to 3.84 kg N/m3/d (R1, 8 cycles/d), and 0.96 to 7.68 kg N/m3/d (R2, 16 cycles/d) by gradually elevating the influent nitrate concentration. Results showed that nitrite production rates increased with the NLRs, with a maximal value of 5.26 kg N/m3/d obtained. However, the compact regular PD granules were not stable and broke down when NLR was above 3.84 kg N/m3/d, which resulted in serious sludge washing out from SBR. The high NLRs led to the extracellular polymeric substances (EPS) transformation in terms of its composition and structure, which the protein content in the EPS and the tightly bound EPS (T-EPS) fraction was significantly decreased, this was supposed to be the major reason causing the breakdown of PD granules. Besides, it was found the PD granule in R2 was more deteriorated than that in R1 under the same high NLR, suggesting the short starvation (idle) times in SBR cycle was likely another reason impairing the stability of PD granules. Overall, this research provides useful information in development of granule-based PD systems and sheds light on achieving high-rate nitrite production in SBR with great stability.
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Affiliation(s)
- Rui Du
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Qingtao Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Shenbin Cao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China; College of Architecture and Civil engineering, Faculty of Architecture, Civil and Transportation Engineering (FACTE), Beijing University of Technology, Beijing 100124, China; Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany.
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29
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Wang Z, Wang H, Nie Q, Ding Y, Lei Z, Zhang Z, Shimizu K, Yuan T. Pb(II) bioremediation using fresh algal-bacterial aerobic granular sludge and its underlying mechanisms highlighting the role of extracellular polymeric substances. JOURNAL OF HAZARDOUS MATERIALS 2023; 444:130452. [PMID: 36435038 DOI: 10.1016/j.jhazmat.2022.130452] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/03/2022] [Accepted: 11/19/2022] [Indexed: 06/16/2023]
Abstract
Lead (Pb) discharged from rural industries poses a significant threat to the environment and human health. Algal-bacterial aerobic granular sludge (A-B AGS) is a promising alternative for sewage treatment with high efficiency and good settleability. In this study, Pb(II) biosorption using fresh A-B AGS was investigated for the first time. The important role of extracellular polymeric substances (EPS) was revealed with the involved mechanisms being clarified. The desorbents for Pb recovery from Pb-loaded A-B AGS were also screened. Results showed that A-B AGS has an excellent maximum Pb adsorption capacity of 72.4 mg·g-1 at pH 6.0. EPS plays an important role in keeping microbial activity, Pb bonding, and providing metal ions (Ca, Na and Mg) for Pb ion exchanges. Electrostatic interaction, ion exchange, and bonding to functional groups may occur orderly in the Pb biosorption process and the formation of pyromorphite (Pb5(PO4)3Cl) contributes to Pb biosorption. About 66 % of the adsorbed Pb was accumulated in the A-B AGS microbial cells. Na2EDTA (0.05 M) can recover 60.3 % of the loaded Pb with the highest microbial activity of granules being remained. All the findings will provide the theoretical basis for the large-scale application of A-B AGS to bioremediate Pb(II)-containing wastewater.
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Affiliation(s)
- Zhiwei Wang
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Hanxiao Wang
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qi Nie
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yi Ding
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
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30
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Liu W, Song J, Wang J, Ji X, Shen Y, Yang D. Achieving robust nitritation in a modified continuous-flow reactor: From micro-granule cultivation to nitrite-oxidizing bacteria elimination. J Environ Sci (China) 2023; 124:117-129. [PMID: 36182122 DOI: 10.1016/j.jes.2021.11.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 11/03/2021] [Accepted: 11/03/2021] [Indexed: 06/16/2023]
Abstract
In this study, a modified continuous-flow nitrifying reactor was successfully operated for rapid cultivation of micro-granules and achieving robust nitritation. Results showed that sludge granulation with mean size of ca. 100 µm was achieved within three weeks by gradually increasing settling velocity-based selection pressure from 0.48 to 0.9 m/hr. Though Nitrospira like nitrite-oxidizing bacteria (NOB) were enriched in the micro-granules with a ratio between ammonia-oxidizing bacteria (AOB) and NOB of 5.7%/6.5% on day 21, fast nitritation was achieved within one-week by gradually increasing of influent ammonium concentration (from 50 to 200 mg/L). Maintaining ammonium in-excess was the key for repressing NOB in the micro-granules. Interestingly, when the influent ammonium concentration switched back to 50 mg/L still with the residual ammonium of 15-25 mg/L, the nitrite accumulation efficiency increased from 90% to 98%. Experimental results suggested that the NOB repression was intensified by both oxygen and nitrite unavailability in the inner layers of micro-granules. Unexpectedly, continuous operation with ammonium in excess resulted in overproduction of extracellular polysaccharides and overgrowth of some bacteria (e.g., Nitrosomonas, Arenimonas, and Flavobacterium), which deteriorated the micro-granule stability and drove the micro-granules aggregation into larger ones with irregular morphology. However, efficient nitritation was stably maintained with extremely high ammonium oxidation potential (> 50 mg/g VSS/hr) and nearly complete washout of NOB was obtained. This suggested that smooth and spherical granule was not a prerequisite for achieving NOB wash-out and maintaining effective nitritation in the granular reactor. Overall, the micro-granules exhibited a great practical potential for high-rate nitritation.
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Affiliation(s)
- Wenru Liu
- National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
| | - Jiajun Song
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Jianfang Wang
- National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Xiaoming Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Yaoliang Shen
- National & Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China; School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Dianhai Yang
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China
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Zhang Z, Wang L, Ji Y, Cao R, Zhou J, Li M, Zhu L, Xu X. Understanding the N-acylated homoserine lactones(AHLs)-based quorum sensing for the stability of aerobic granular sludge in the aspect of substrate hydrolysis enhancement. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159581. [PMID: 36397605 DOI: 10.1016/j.scitotenv.2022.159581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/08/2022] [Accepted: 10/16/2022] [Indexed: 06/16/2023]
Abstract
Efficient substrate metabolism is the premise for stable operation of aerobic granular sludge and can be regulated by quorum sensing (QS). In this study, starch and acetate were selected to represent complex and simple substrates to provide comparable amount of metabolic energy for granules cultivation. Starch-fed granules were larger in size and contained higher EPS content than acetate-fed granules, though both granules exhibited similar substrate-degradation rates during sequencing batch reactor (SBR) cycle. Three N-acylhomoserine lactones (AHLs), including C8-HSL, 3OHC8-HSL and 3OHC12-HSL, were detected as dominant autoinducers in granules. They accumulated more in starch-fed granules than acetate-fed granules. The batch experiments were implemented to investigate QS regulation for granular stability in terms of substrate hydrolysis and transformation. The addition of three AHLs increased the activity of α-amylase, the main starch hydrolase, 4-6 times, significantly (p < 0.01) higher than the control treatment without AHLs amendment. While activity of dehydrogenase, the main simple substrate degradation enzyme, was increased only 1-2 times. Higher enzyme activity, especially α-amylase, significantly (p < 0.05) promoted the substrate-degradation rate (65 % than control group) and EPS yield in starch-fed system. Overall, QS can facilitate complex substrate uptake via hydrolysis enhancement and EPS secretion, which together promote sludge granulation and stability.
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Affiliation(s)
- Zhiming Zhang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Linlin Wang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yatong Ji
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Runjuan Cao
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiaheng Zhou
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Mengyan Li
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark 07102, USA
| | - Liang Zhu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou 310058, China.
| | - Xiangyang Xu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou 310058, China
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Li YS, Li BB, Tian T, Yu HQ. Quorum sensing unveils the sludge floccule-assisted stabilization of aerobic granules in granule-dominated sequencing batch reactors. Biotechnol Bioeng 2023; 120:444-455. [PMID: 36303067 DOI: 10.1002/bit.28275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 10/19/2022] [Accepted: 10/23/2022] [Indexed: 01/13/2023]
Abstract
Floccules are another major form of microbial aggregates in aerobic granular sludge systems. Previous studies mainly attributed the persistence of floccules to their relatively faster nutrient uptake and higher growth rate over aerobic granules; however, they failed to unravel the underlying mechanism of the long-term coexistence of these two aggregates. In this work, the existence and function of the floccules in an aerobic granule-dominated sequencing batch reactor were investigated from the view of quorum sensing (QS) and quorum quenching (QQ). The results showed that though the floccules were closely associated with the granules in terms of similar community structures (including the QS- and QQ-related ones), they exhibited a relatively higher QQ-related activity but a lower QS-related activity. A compatible proportion of floccules might be helpful to maintain the QS-related activity and keep the granules stable. In addition, the structure difference was demonstrated to diversify the QS- and QQ-related activities of the floccules and the aerobic granules. These findings could broaden our understanding of the interactions between the coexistent floccules and granules in aerobic granule-dominated systems and would be instructive for the development of the aerobic granular sludge process.
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Affiliation(s)
- Yu-Sheng Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
| | - Bing-Bing Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
| | - Tian Tian
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China.,Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science & Technology of China, Hefei, China
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Ouyang L, Qiu B. Positive effects of magnetic Fe 3O 4@polyaniline on aerobic granular sludge: Aerobic granulation, granule stability and pollutants removal performance. BIORESOURCE TECHNOLOGY 2023; 368:128296. [PMID: 36370942 DOI: 10.1016/j.biortech.2022.128296] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 06/16/2023]
Abstract
The magnetic material has been determined to have a positive effect on sludge granulation and wastewater treatment performance. In this study, the effect of magnetic Fe3O4@polyaniline (Fe3O4@PANI) on aerobic granulation, granule stability, and pollutants removal performance was evaluated by adding it into a sequencing batch reactor to cultivate aerobic granular sludge (AGS). The results indicated that the composite combined the advantages of PANI and Fe3O4 to promote the formation of AGS during the granulation period. The Fe3O4@PANI stimulated the granules to secrete extracellular polymeric substances with a higher proteins/polysaccharides ratio, thus enhancing the stability of the AGS. In addition, microbial community analysis revealed that the great performance of the AGS on denitrification and phosphorus removal could be attributed to the enrichment of denitrifying bacteria, phosphorus accumulating organisms (PAO), and denitrifying PAO by Fe3O4@PANI. Thus, Fe3O4@PANI has been demonstrated to have a positive effect on the formation and stability of AGS.
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Affiliation(s)
- Lingfeng Ouyang
- Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Sciences & Engineering, Beijing Forestry University, Beijing 100083, China
| | - Bin Qiu
- Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Sciences & Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, Beijing Forestry University, Beijing 100083, China.
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34
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Kosar S, Isik O, Cicekalan B, Gulhan H, Cingoz S, Yoruk M, Ozgun H, Koyuncu I, van Loosdrecht MCM, Ersahin ME. Coupling high-rate activated sludge process with aerobic granular sludge process for sustainable municipal wastewater treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 325:116549. [PMID: 36419284 DOI: 10.1016/j.jenvman.2022.116549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 09/28/2022] [Accepted: 10/15/2022] [Indexed: 06/16/2023]
Abstract
Achieving a neutral/positive energy balance without compromising discharge standards is one of the main goals of wastewater treatment plants (WWTPs) in terms of sustainability. Aerobic granular sludge (AGS) technology promises high treatment performance with low energy and footprint requirement. In this study, high-rate activated sludge (HRAS) process was coupled to AGS process as an energy-efficient pre-treatment option in order to increase energy recovery from municipal wastewater and decrease the particulate matter load of AGS process. Three different feeding strategies were applied throughout the study. AGS system was fed with raw municipal wastewater, with the effluent of HRAS process, and with the mixture of the effluent of HRAS process and raw municipal wastewater at Stage 1, Stage 2 and Stage 3, respectively. Total suspended solids (TSS), chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), and total phosphorus (TP) concentrations in the effluent were less than 10 mg/L, 60 mg/L, 0.4 mg/L, and 1.3 mg/L respectively at all stages. Fluctuations were observed in the denitrification performance due to changes in the influent COD/total nitrogen (TN) ratio. This study showed that coupling HRAS process with AGS process by feeding the AGS process with the mixture of HRAS process effluent and raw municipal wastewater could be an appropriate option for both increasing the energy recovery potential of WWTPs and enabling high effluent quality.
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Affiliation(s)
- Sadiye Kosar
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey.
| | - Onur Isik
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey; Kahramanmaras Sutcu Imam University, Engineering and Architecture Faculty, Environmental Engineering Department, Onikisubat, 46100, Kahramanmaras, Turkey
| | - Busra Cicekalan
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
| | - Hazal Gulhan
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
| | - Seyma Cingoz
- ISKI, Istanbul Water and Sewerage Administration, Eyup, 34060, Istanbul, Turkey
| | - Mustafa Yoruk
- ISKI, Istanbul Water and Sewerage Administration, Eyup, 34060, Istanbul, Turkey
| | - Hale Ozgun
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
| | - Ismail Koyuncu
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
| | - Mark C M van Loosdrecht
- Delft University of Technology, Department of Biotechnology, van der Maasweg 9, 2629, HZ, Delft, the Netherlands
| | - Mustafa Evren Ersahin
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
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Feasibility Study of Applying Anaerobic Step-Feeding Mode for the Treatment of High-Strength Wastewater in Granular Sequencing Batch Reactors (GSBRs). Processes (Basel) 2022. [DOI: 10.3390/pr11010075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
This study investigated the feasibility of applying an anaerobic step-feeding strategy to enhance the performance of granular sequencing batch reactors (GSBRs) in terms of operational stability of the cultivated mature granules and nutrient removal efficiencies. Two identical 5 L reactors were operated with a total cycle time of 8 h. GSBRs were operated with high-strength synthetic wastewater (COD = 1250 ± 43, ammonium (NH4-N) = 115.2 ± 4.6, and orthophosphate (PO4-P) = 17.02 ± 0.9 mg/L) for 360 days through three stages: (1) Cultivation, 125 days (>2.1 mm); (2) Maturation, 175 days (>3 mm); (3) alternate feed loading strategy for R2 only for 60 days (anaerobic step-feeding). The granulation process, the physical properties of the granules, the nutrients, and the substrate removal performance were recorded during the entire operational period. For the cultivation and maturation stages, both reactors followed the fast single feeding mode followed by anaerobic mixing, and the results indicated a strong correlation between R1 and R2 due to the same working conditions. During the cultivation stage, adopting high organic loading rate (OLR) at the reactor start-up did not accelerate the formation of granules. Removal efficiency of PO4-P was less than 76% during the maturation period, while it exceeded 90% for COD, and was higher than 80% for NH4-N without effect of nitrite or nitrate accumulations due to simultaneous nitrification–denitrification. After changing filling mode for R2 only, there was unexpected deterioration in the performance and a rapid disintegration of the matured granules (poor settleability) accompanied by poor effluent quality due to high content of suspended solids because of applying selection pressure of short settling time. Consequently, GSBRs operation under the effect of fast single feeding mode followed by anaerobic mixing favors stable long-term granule stability.
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36
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Campo R, Carretti E, Lubello C, Lotti T. Recovery of structural extracellular polymeric substances (sEPS) from aerobic granular sludge: Insights on biopolymers characterization and hydrogel properties for potential applications. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 324:116247. [PMID: 36174471 DOI: 10.1016/j.jenvman.2022.116247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/07/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Nowadays, wastewater treatment plants (WWTPs) are transforming into water resource recovery facilities (WRRFs) where the resource recovery from waste streams is pivotal. Aerobic granular sludge (AGS) is a novel technology applied for wastewater treatment. Extracellular polymeric substances (EPS) secreted by microorganisms promote the aggregation of bacterial cells into AGS and the structural fraction of EPS (sEPS) is responsible for the mechanical properties of AGS. sEPS can be extracted and recovered from waste AGS by physico-chemical methods and its characterization is to date of relevant concern to understand the properties in the perspective of potential applications. This study reports on: characterization of sEPS extracted and recovered from AGS; - formation and characterization of sEPS-based hydrogels. Briefly, sEPS were extracted by a thermo-alkaline process followed by an acidic precipitation. sEPS-based hydrogels were formed by a cross-linking process with a 2.5% w/w CaCl2 solution. The following key-findings can be drawn: i) hydrogels can be formed starting from 1% w/w sEPS on, by diffusion of Ca2+ into sEPS network; ii) the Ca/C molar ratio of hydrogels decreased with increasing concentration of sEPS from 1 to 10% w/w; iii) the thermogravimetric and spectroscopic behaviours of sEPS show that the cross-linking reaction mainly involves the polysaccharidic fraction of biopolymers; iv) water-holding capacity up to 99 gH2O/gsEPS was registered for 1% w/w sEPS-based hydrogels, suggesting applications in several industrial sectors (i.e. chemical, paper, textile, agronomic, etc.); v) rheological results highlighted a solid-like behaviour (G'≫G") of sEPS-based hydrogels. The power-law fitting of G' vs. sEPS concentration suggests that the expansion of the sEPS network during cross-linking occurs through a percolative mechanism involving the initial formation of sEPS oligomers clusters followed by their interconnection towards the formation of 3D network. These findings provide additional information about the mechanisms of sEPS-based hydrogel formation and reveal the peculiar physico-chemical characteristics of sEPS which nowadays are increasingly gaining interest in the context of resource recovery.
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Affiliation(s)
- Riccardo Campo
- Department of Civil and Environmental Engineering - (DICEA), University of Florence, Florence, Italy.
| | - Emiliano Carretti
- Department of Chemistry "Ugo Schiff" & CSGI Consortium, University of Florence, Italy
| | - Claudio Lubello
- Department of Civil and Environmental Engineering - (DICEA), University of Florence, Florence, Italy
| | - Tommaso Lotti
- Department of Civil and Environmental Engineering - (DICEA), University of Florence, Florence, Italy
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37
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Ji Y, Cao R, Wang C, Xu X, Zhu L. Effect of flow regime on mass transfer diffusion and stability of aerobic granular sludge (AGS) in view of interfacial thermodynamic. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 323:116293. [PMID: 36261993 DOI: 10.1016/j.jenvman.2022.116293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 08/21/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Aerobic granular sludge (AGS) technology has been widely studied as "The Next Generation Wastewater Treatment technology". The effect of hydraulic conditions on the structural stability of AGS has been widely studied. However, the function of flow regime on the AGS stability, especially dissolved oxygen (DO) mass transfer, is still unknown. In this study, we used the Reynolds number (Re) to quantify the flow regime and selected different stages of AGS as experimental subjects. Results showed that the relatively suitable Re (Re = 150) could create lower DO mass transfer limitation (Lc = 27.4 μm) and increase protein (PN) contents and the abundance of hydrophobic functional groups in AGS. At this condition (Re = 150), the interfacial Gibbs free energy of sludge-water (ΔGLSa) was at a lower state (-129.75 ± 2.15 mJ·m-2), which favored the stability of AGS. Principal component analysis (PCA) and correlation analysis indicated that the response of ΔGLSa was affected by Lc, PN, and hydrophobic groups. In addition, results obtained for unstable AGS further verified that suitable Re regulates the structural stability of AGS. This study deepens the understanding of Re as an important hydraulic parameter for structural stability of AGS, which is also of great significance for energy saving of sequential batch reactors (SBRs) with agitation in practical engineering.
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Affiliation(s)
- Yatong Ji
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Runjuan Cao
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Chen Wang
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Xiangyang Xu
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou, 310058, China
| | - Liang Zhu
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou, 310058, China.
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38
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Jiang Y, Shang Y, Zhang W, Zhang X, Li J, Shao S. Assessing the effect of SiO 2 and TiO 2 nanoparticles on granule stability and microbial community shift in aerobic granular sludge process. CHEMOSPHERE 2022; 307:135677. [PMID: 35843432 DOI: 10.1016/j.chemosphere.2022.135677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/19/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023]
Abstract
The widely used SiO2 and TiO2 nanoparticles (NPs) can accumulate in industrial wastewaters, thereby posing challenge to biological wastewater treatment processes. In this work, the performance of aerobic granular sludge (AGS) reactors fed with wastewater containing 50 mg L-1 SiO2 and TiO2 NPs were investigated. The results showed that the granules could resist the NPs in wastewater (no disintegration of granules was observed). SiO2 NPs had a negative effect on the settleability of granules, with the SVI30 increased by 64.5% and protein secretion decreased by 29.9%. To the contrary, the settleability of granules was improved in the presence of TiO2 NPs due to the increase of the protein secretion. Possibly because of the compact and layered structure of granules, in the presence of both types of NPs, no obvious reduction of the overall removal efficiency of organics was found, and nanoparticle-resistant strains were enriched. The overall nitrification and denitrification efficiencies were hardly affected by SiO2 NPs while significantly inhibited by TiO2 NPs. Some functional genera, such as Hyphomicrobium and Acidovorax, showed growth inhibition with TiO2 NPs, which might be responsible for the reduction of nitrification and denitrification efficiencies.
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Affiliation(s)
- Yu Jiang
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, China
| | - Yu Shang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Wei Zhang
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China
| | - Xiangling Zhang
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, China
| | - Jiangyun Li
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Senlin Shao
- School of Civil Engineering, Wuhan University, Wuhan 430072, China.
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The biofilm life cycle: expanding the conceptual model of biofilm formation. Nat Rev Microbiol 2022; 20:608-620. [PMID: 35922483 PMCID: PMC9841534 DOI: 10.1038/s41579-022-00767-0] [Citation(s) in RCA: 275] [Impact Index Per Article: 137.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2022] [Indexed: 01/18/2023]
Abstract
Bacterial biofilms are often defined as communities of surface-attached bacteria and are typically depicted with a classic mushroom-shaped structure characteristic of Pseudomonas aeruginosa. However, it has become evident that this is not how all biofilms develop, especially in vivo, in clinical and industrial settings, and in the environment, where biofilms often are observed as non-surface-attached aggregates. In this Review, we describe the origin of the current five-step biofilm development model and why it fails to capture many aspects of bacterial biofilm physiology. We aim to present a simplistic developmental model for biofilm formation that is flexible enough to include all the diverse scenarios and microenvironments where biofilms are formed. With this new expanded, inclusive model, we hereby introduce a common platform for developing an understanding of biofilms and anti-biofilm strategies that can be tailored to the microenvironment under investigation.
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40
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Pomdaeng P, Chu CY, Sripraphaa K, Sintuya H. An accelerated approach of biogas production through a two-stage BioH 2/CH 4 continuous anaerobic digestion system from Napier grass. BIORESOURCE TECHNOLOGY 2022; 361:127709. [PMID: 35905883 DOI: 10.1016/j.biortech.2022.127709] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/23/2022] [Accepted: 07/23/2022] [Indexed: 06/15/2023]
Abstract
Napier grass found to be greatest potential for gaseous bioenergy production. The biohydrogen and biomethane productions from untreated Napier grass in single and two-stage continuous bioreactors was evaluated using anaerobic digestion technology. The bioreactors were fed Napier grass with organic loading rate (OLR) of 0.5, 1.0 and 2.0 kg VS/m3-d, respectively. The hydrogen, methane, and energy yields were evaluated. The methane yield of single-stage system was 282.08 CH4/g vS with OLR of 0.5 kg VS/m3-d. For two-stage system, the biohydrogen and biomethane yields were 90.06 mL H2/g vS and 367.00 mL CH4/g vS with OLRs of 1.0 and 0.5 kg VS/m3-d, respectively. The energy yields of single and two-stage systems were 13.14 and 10.10 kJ/g vS respectively. The peak OLR of Napier grass was 0.5 kg VS/m3-d for the two-stage system whereas the total energy recovery was 30 % higher than the single-stage system.
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Affiliation(s)
- Prakaidao Pomdaeng
- Asian Development College for Community Economy and Technology (adiCET), Chiang Mai Rajabhat University, Thailand; Master's Program of Green Energy Science and Technology, Feng Chia University, Taiwan
| | - Chen-Yeon Chu
- Master's Program of Green Energy Science and Technology, Feng Chia University, Taiwan; Institute of Green Products, Feng Chia University, Taiwan.
| | - Kobsak Sripraphaa
- National Electronics and Computer Technology Center (NECTEC), National Science and Technology Development Agency (NSTDA), Thailand
| | - Hathaithip Sintuya
- Asian Development College for Community Economy and Technology (adiCET), Chiang Mai Rajabhat University, Thailand
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41
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Guo Y, Zhang B, Feng S, Wang D, Li J, Shi W. Unveiling significance of Ca 2+ ion for start-up of aerobic granular sludge reactor by distinguishing its effects on physicochemical property and bioactivity of sludge. ENVIRONMENTAL RESEARCH 2022; 212:113299. [PMID: 35430279 DOI: 10.1016/j.envres.2022.113299] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 04/01/2022] [Accepted: 04/09/2022] [Indexed: 06/14/2023]
Abstract
Almost all of the aerobic granular sludge (AGS) reactors were fed on certain amounts of Ca2+ ion, but whether and why it was necessary for reactor start-up remain unknown. Herein, this study conducted a set of comparative experiments in three AGS reactors, which were operated in parallel with Ca2+ addition in R3, hydroxyapatite (HAP) addition in R1, and without any forms of Ca addition in R2. Results showed that R3 not only achieved the complete granulation of sludge, but exhibited superior performance of COD and nutrient removal. In contrast, R1 had a slightly quicker granulation rate than R3 (R1: 0.07 day-1; R3: 0.06 day-1), but the formed granules could not efficiently degrade pollutants. In R2, both sludge granulation and pollutants removal did not proceed normally. Further investigations found that the Ca2+ ion acted in three ways: (1) it increased inorganic composition of sludge to promote granulation; (2) the transformed HAP strengthened stability of granular structure; (3) it ensured bioactivity of granules by driving enrichment of functional microbes and synthesis of metabolism enzymes. Overall, this study systemically proved significance of Ca2+ ion for the start-up of AGS reactors and its influencing mechanisms on different properties of granules.
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Affiliation(s)
- Yuan Guo
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, China
| | - Bing Zhang
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China
| | - Siqi Feng
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, China
| | - Dongqi Wang
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, China
| | - Jiake Li
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, China
| | - Wenxin Shi
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China.
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42
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Xu P, Xie Z, Shi L, Yan X, Fu Z, Ma J, Zhang W, Wang H, Xu B, He Q. Distinct responses of aerobic granular sludge sequencing batch reactors to nitrogen and phosphorus deficient conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 834:155369. [PMID: 35461925 DOI: 10.1016/j.scitotenv.2022.155369] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/14/2022] [Accepted: 04/14/2022] [Indexed: 06/14/2023]
Abstract
The nutrients availability determines efficiency of biological treatment systems, along with the structure and metabolism of microbiota. Herein nutrients deficiencies on aerobic granular sludge were comparatively evaluated, treating wastewater with mass ratios of chemical oxygen demand : nitrogen : phosphorus being 200:20:4, 200:2:4, and 200:20:0.4 (deemed as nutrient-balanced, nitrogen-deficient, and phosphorus-deficient), respectively. Results revealed that both nitrogen and phosphorus deficiencies significantly raised the effluent qualities especially nitrogen removal. However, nitrogen deficiency aroused considerable growth of filamentous bacteria, while granules kept compact structure under phosphorus deficient condition. Extracellular polymeric substances (EPS) also varied in contents and structures in response to different wastewaters. Microbial community structure analysis demonstrated that nitrogen deficiency led to lower richness and higher diversity, while the reverse was observed under phosphorus deficient condition. Nitrogen deficiency mainly induced decrease of nitrifying bacteria, while similarly phosphorus deficiency led to loss of phosphorus accumulating organisms. Dramatic enrichment Candidatus_Competibacter and filamentous Thiothrix were found under nutrients deficiencies, in which the latter explained and indicated filamentous bulking potential especially under nitrogen limited condition. Bacterial metabolism patterns verified the functions of microbial community responding to nutrients via PICRUSt2 prediction mainly by up-regulating cell motility, and cellular processes and signaling. This study could aid understanding of long-term stability of aerobic granular sludge for low-strength wastewater treatment.
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Affiliation(s)
- Peng Xu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Zhiyi Xie
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Liangsheng Shi
- Hubei Key Laboratory of Water System Science for Sponge City Construction, Wuhan University, Wuhan, 430072, China
| | - Xiaohui Yan
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Zhidong Fu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Jingwei Ma
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Wei Zhang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Baokun Xu
- Hubei Key Laboratory of Water System Science for Sponge City Construction, Wuhan University, Wuhan, 430072, China; Agricultural Water Conservancy Department, Changjiang River Scientific Research Institute, Wuhan 430010, China
| | - Qiulai He
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China; Hubei Key Laboratory of Water System Science for Sponge City Construction, Wuhan University, Wuhan, 430072, China.
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43
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Tsertou E, Caluwé M, Goossens K, Dobbeleers T, Dockx L, Poelmans S, Suazo KS, Dries J. Is building up substrate during anaerobic feeding necessary for granulation? WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 86:763-776. [PMID: 36038975 DOI: 10.2166/wst.2022.236] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
For a successful granulation process in activated sludge systems, the stimulation of slow growing organisms such as glycogen accumulating microorganisms (GAOs) is a key factor. Here we show that the introduction of an anaerobic feast followed by an aerobic famine phase successfully transforms bulking sludge, caused by the abundance of genus Kouleothrix, to a hybrid floccular-granular sludge. Two sequencing batch reactors (SBRs) were operated for 228 days treating the same industrial wastewater derived from the cleaning of trucks transporting liquid food (the cargo consists of approximately 70% chocolate and 30% beer). By respectively applying a fast and slow feeding in two parallel SBRs, different degrees of substrate build-up were achieved in the two reactors during the feast phase. The F/M ratio over the feeding time was 1.41 ± 0.48 and 0.57 ± 0.16 kg COD·(kg VSS*d)-1 for the fast-fed and the slow-fed SBR respectively. Our results demonstrate that substrate build-up during the anaerobic selection step is not necessary to obtain well-settling granular-like sludge.
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Affiliation(s)
- Eirini Tsertou
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Michel Caluwé
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Koen Goossens
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Thomas Dobbeleers
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Lennert Dockx
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Sven Poelmans
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Karina Seguel Suazo
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
| | - Jan Dries
- Research Group BioWAVE, Biochemical Wastewater Valorization & Engineering, Faculty of Applied Engineering, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171-2020, Antwerp E-mail:
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Trancone G, Spasiano D, Race M, Luongo V, Petrella A, Pirozzi F, Fratino U, Piccinni AF. A combined system for asbestos-cement waste degradation by dark fermentation and resulting supernatant valorization in anaerobic digestion. CHEMOSPHERE 2022; 300:134500. [PMID: 35395263 DOI: 10.1016/j.chemosphere.2022.134500] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 03/14/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
The use of biological processes for the treatment of asbestos cement waste (ACW) has gained interest in recent years. Nevertheless, this methodology is not yet consolidated because of the incomplete ACW conversion during the biological treatment and the consequent need for further treatments that generally require a high amount of energy and chemicals. In this study, the efficiency of both mesophilic and thermophilic dark fermentation (DF) fed with glucose in fed-batch conditions was assessed for ACW biological treatment. Both thermophilic and mesophilic DF of glucose resulted in a partial conversion of glucose into organic acids that successfully degraded all the asbestos fibers contained in an ACW sample. A hydrogen-rich biogas was produced as well: at the end of the mesophilic DF treatment 0.14 LH2 gglucose-1 were obtained. In addition, the anaerobic digestion (AD) of the DF supernatants led to the production of 0.38 LCH4 gCOD-1.
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Affiliation(s)
- G Trancone
- Department of Civil, Building and Environmental Engineering, University of Naples Federico II, Via Claudio, 21, 80125, Napoli, Italy
| | - D Spasiano
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Via E. Orabona, 4, 70125, Bari, Italy.
| | - M Race
- Department of Civil and Mechanical Engineering, Università di Cassino e del Lazio Meridionale, Viale dell'Università, 03043, Cassino, Italy
| | - V Luongo
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples Federico II, Via Cintia, Monte S. Angelo, Napoli, 80126, Italy
| | - A Petrella
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Via E. Orabona, 4, 70125, Bari, Italy
| | - F Pirozzi
- Department of Civil, Building and Environmental Engineering, University of Naples Federico II, Via Claudio, 21, 80125, Napoli, Italy
| | - U Fratino
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Via E. Orabona, 4, 70125, Bari, Italy
| | - A F Piccinni
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Via E. Orabona, 4, 70125, Bari, Italy
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Chen X, Wang J, Wang Q, Li Z, Yuan T, Lei Z, Zhang Z, Shimizu K, Lee DJ. A comparative study on simultaneous recovery of phosphorus and alginate-like exopolymers from bacterial and algal-bacterial aerobic granular sludges: Effects of organic loading rate. BIORESOURCE TECHNOLOGY 2022; 357:127343. [PMID: 35605775 DOI: 10.1016/j.biortech.2022.127343] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/15/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
The effects of organic loading rate (OLR) on simultaneous phosphorus (P) and alginate-like exopolymers (ALE) recovery from bacterial aerobic granular sludge (AGS) and algal-bacterial AGS were examined and compared during 70 days' operation. With the increase of OLR (0.6-1.2 g COD/(L·day)), both AGS showed good settleability and granular strength with P bioavailability > 92% (Stage III). The moderate increase in OLR had a positive influence on simultaneous recovery of P and ALE. On day 60, the contents of ALE and guluronic acid/guluronic acid (GG) blocks reached the highest in algal-bacterial AGS, about 13.37 and 2.13 mg/g-volatile suspended solids (VSS), respectively. Meanwhile, about daily 0.55 kg of P is estimated to be recovered from the wastewater treatment plant with a treatment capacity of 10,000 m3/day. P mass balance analysis during ALE extraction from both AGS was conducive to further evaluation of P removal pathway and its application potentials.
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Affiliation(s)
- Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Jixiang Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qian Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zejiao Li
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
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46
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Phosphorus Removal from Aerobic Granular Sludge: Proliferation of Polyphosphate-Accumulating Organisms (PAOs) under Different Feeding Strategies. Processes (Basel) 2022. [DOI: 10.3390/pr10071399] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Aerobic granular sludge (AGS) is known for high phosphorus removal from wastewaters, and phosphorus can be recovered from high phosphorus-containing waste sludge granules. This study aimed at determining the feeding strategy that provides the best performance in terms of the proliferation of polyphosphate-accumulating organisms (PAOs) and phosphorus removal. Using three AGS bioreactors, this study compared phosphorus removal and the proliferation dynamics of PAOs under three different feeding strategies: anaerobic slow feeding (R1), pulse feeding + anaerobic mixing (R2), and pulse feeding (R3). Results indicate that R1 and R2 achieved significantly higher phosphorus removal (97.6 ± 3% for R1 and 98.3 ± 1% for R2) than R3 (55 ± 11%). The anaerobic slow feeding procedure (R1) achieved the highest specific phosphorus release rate (SPRR) and specific phosphorus uptake rate (SPUR) as compared to the other two feeding conditions. 16S ribosomal ribonucleic acid (rRNA) gene sequencing assay of the microbial community for the three feeding strategies indicated that although the feeding strategy impacted reactor performance, it did not significantly alter the microbial community. The bacteria community composition maintained a similar degree of diversity. Proteobacteria, Bacteroidetes, and Verrucomicrobia were the dominant bacterial phyla in the system. Dominant PAOs were from the class Betaproteobacteria and the genera Paracoccus and Thauera. Glycogen-accumulating organisms were significantly inhibited while other less-known bacteria such as Wandonia and Hyphomonas were observed in all three reactors.
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47
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Cai W, Hu P, Li Z, Kang Q, Chen H, Zhang J, Zhu S. Effect of high ammonia on granular stability and phosphorus recovery of algal-bacterial granules in treatment of synthetic biogas slurry. Heliyon 2022; 8:e09844. [PMID: 35815122 PMCID: PMC9263998 DOI: 10.1016/j.heliyon.2022.e09844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/17/2022] [Accepted: 06/28/2022] [Indexed: 12/03/2022] Open
Abstract
The aim of the study was to investigate the application of algal-bacterial granules in treatment of high ammonia wastewater. Two identical cylindrical reactors, i.e., Rc and Rs was used to develop granular sludge system with synthetic biogas slurry. Rs was run under an artificial solar lamp controlled at 12 h power on and 12 h power off (∼10,000 lux); Rc was operated as control (no light). Results showed that algal-bacterial granules (ABGS) developed in Rs exhibited better structural stability in the face of high ammonia influent. Compared with aerobic granules (AGS), ABGS possessed high proteins (PN) content (145.3 mg/g-VSS) in extracellular polymeric substances (EPS) and better O2 mass transfer inner granules. Higher phosphorus (P) removal capacity was obtained in Rs even under 400 mg/L NH3–N which resulted in higher P content in ABGS biomass (56.4 mg/g-TSS). Bioavailable P in ABGS was 44 mg P/g-SS on day 160, approximately 1.53-times higher than that in AGS.
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48
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P S G da Silva VE, de S Rollemberg SL, da S E Santos SG, C V Silva TF, P Vilar VJ, B Dos Santos A. Landfill leachate biological treatment: perspective for the aerobic granular sludge technology. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:45150-45170. [PMID: 35486275 DOI: 10.1007/s11356-022-20451-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
Landfill leachates are high-strength complex mixtures containing dissolved organic matter, ammonia, heavy metals, and sulfur species, among others. The problem of leachate treatment has subsisted for some time, but an efficient and cost-effective universal solution capable of ensuring environmental resources protection has not been found. Aerobic granular sludge (AGS) has been considered a promising technology for biological wastewater treatment in recent years. Granules' layered structure, with an aerobic outer layer and an anaerobic/anoxic core, enables the presence of diverse microbial populations without the need for support media, allowing simultaneous removal of different pollutants in a single unit. Besides, its strong and compact arrangement provides higher tolerance to toxic pollutants and the ability to withstand large load fluctuations. Furthermore, its good that settling properties allow high biomass retention and better sludge separation. Nevertheless, AGS-related research has focused on carbon-nitrogen-phosphorus removal, mainly from sanitary sewage. This review aims to summarize and analyze the main findings and problems reported in the literature regarding AGS application to landfill leachate treatment and identify the knowledge gaps for future applications.
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Affiliation(s)
- Vicente E P S G da Silva
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Silvio L de S Rollemberg
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Sara G da S E Santos
- LSRE-LCM - Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Tânia F C V Silva
- LSRE-LCM - Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Vítor J P Vilar
- LSRE-LCM - Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - André B Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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Amin Vieira da Costa NP, Libardi N, Ribeiro da Costa RH. How can the addition of extracellular polymeric substances (EPS)-based bioflocculant affect aerobic granular sludge (AGS)? JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 310:114807. [PMID: 35231689 DOI: 10.1016/j.jenvman.2022.114807] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/19/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
The ability of extracellular polymeric substances (EPS) recovered from aerobic granular sludge (AGS) to act as bioflocculant was tested in a pilot-scale sequencing batch reactor (SBR), fed with low-strength municipal wastewater. EPS were compared with the addition of Na-alginate as a standardized biopolymer. The optimal dosage of both biopolymers was determined through jar-test assays (400 mg L-1 of Na-alginate in a 250 mg Ca L-1 and 50 mg L-1 of EPS in pH of 2 ± 0.2). The addition of Na-alginate (Operational Period I- OP-I) and EPS (Operational Period II - OP-II) led to increased adhesion of particles with 2.9 ± 0.45 and 1.3 ± 0.3 g TSS L-1 during OP-I and OP-II, respectively, and fast settling biomass (SVI30 between 68 and 78 mL g-1). Granule predominance occurred at early stages of OP-I (day 37) and OP-II (day 44), presenting diameters mainly within the 212-600 μm range. The reactor showed removal efficiencies of 85% for biochemical oxygen demand (BOD) and above 50% for N-NH4 during the study periods. Furthermore, the addition of EPS as a bioflocculant promoted a substantial increase in polysaccharides (PS = 153.01 ± 121 mg gVSS-1) and proteins (PN = 121.96 ± 69 mg gVSS-1), while the addition of Na-alginate affected mostly the PS content (87 ± 24 mg gVSS-1). The microbial community shifted mainly from Betaproteobacteria (45%) during OP-I to Alphaproteobacteria (64%) in OP-II. Therefore, EPS affected both physical-chemical and microbial features of the AGS biomass without any change in treatment efficiencies. EPS is a promising resource to be recovered from aerobic granular sludge and to be used as an alternative and sustainable bioflocculant.
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Affiliation(s)
| | - Nelson Libardi
- Department of Sanitary and Environmental Engineering, Federal University of Santa Catarina - UFSC, 88040-970, Florianópolis, Brazil.
| | - Rejane Helena Ribeiro da Costa
- Department of Sanitary and Environmental Engineering, Federal University of Santa Catarina - UFSC, 88040-970, Florianópolis, Brazil
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50
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Ji Y, Chen L, Cao R, Zhang Z, Zuo P, Xu X, Zhu L. Uncover the secret of the stability and interfacial Gibbs free energy of aerobic granular sludge. ENVIRONMENTAL RESEARCH 2022; 208:112693. [PMID: 35065066 DOI: 10.1016/j.envres.2022.112693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 12/31/2021] [Accepted: 01/04/2022] [Indexed: 06/14/2023]
Abstract
Interfacial Gibbs free energy (IGFE) as a thermodynamic indicator characterize the stability of the natural system. For aerobic granular sludge (AGS), how IGFE determines the stability of sludge remains to be determined. The Gibbs free energy change at the AGS-water interface (ΔGswa) and AGS interfaces (ΔGsc) were selected as the main interfacial thermodynamic factors. Results indicated that the stable AGS was guaranteed with ΔGsc at the range of -31 to - 46 J m-2. Pearson correlation coefficients between ΔGswa/ ΔGsc and relative hydrophobicity, water content, SVI30, integrity coefficient were -0.9, 0.8, 0.85, and 0.84, which illustrated that the IGFE could be a more comprehensive thermodynamic indicator. Microbial community and EPS analysis verified the importance of denitrifiers, Amide III, protein-like substances for AGS stability. This work offers a new insight into the development of AGS stability based on IGFE.
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Affiliation(s)
- Yatong Ji
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Linlin Chen
- School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Runjuan Cao
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Zhiming Zhang
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Pengxiao Zuo
- Department of Civil and Environmental Engineering, Rice University, Houston, TX, 77005, USA
| | - Xiangyang Xu
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou, 310058, China
| | - Liang Zhu
- Institution of Environment Pollution Control and Treatment, Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou, 310058, China; Zhejiang Provincial Engineering Laboratory of Water Pollution Control, 388 Yuhangtang Road, Hangzhou, 310058, China.
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