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Du Z, Lu B, Li D, Chai X. Strengthening nitrogen removal of rural wastewater treatment in humus biochemical system under low dissolved oxygen conditions: Sludge and microbial characteristics. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121762. [PMID: 39067308 DOI: 10.1016/j.jenvman.2024.121762] [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: 04/06/2024] [Revised: 06/20/2024] [Accepted: 07/04/2024] [Indexed: 07/30/2024]
Abstract
To achieve efficient and cost-effective treatment for the rural wastewater, a novel humus biochemical system (HBS) process derived from humus bio-functional material was proposed to treat rural wastewater under low dissolved oxygen (DO) conditions, and the operational performance, sludge characteristics, and microbial community in HBS were systematically investigated in this study. The results indicated that the HBS reactor could be operated stably under low DO levels of 0.2-0.8 mg/L, and maintained high removal efficiencies of 96.4%, 96.0%, and 88.2% for chemical oxygen demand, ammonia nitrogen, and total nitrogen, with corresponding effluent concentrations of 11.0, 1.7, and 5.1 mg/L, respectively. The sludge produced from HBS was characterized by relatively large particle size, complex structural morphology, and abundant humic substances, which favorably improved the system stability. Illumina sequencing demonstrated that HBS reactor possessed high microbial abundance and diversity and was enriched with plenty of nitrifying and denitrifying bacteria, which synergistically intensified the whole biological nitrogen removal process in this system. The study presented the feasibility and adaptability of HBS for energy-efficient rural wastewater treatment.
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Affiliation(s)
- Zhengliang Du
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Bin Lu
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Dong Li
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Xiaoli Chai
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
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Liu Z, Yang R, Zhang D, Wang J, Gao M, Zhang A, Liu W, Liu Y. Insight into the effect of particulate organic matter on sludge granulation at the low organic load: Sludge characteristics, extracellular polymeric substances and microbial communities response. BIORESOURCE TECHNOLOGY 2023; 388:129791. [PMID: 37730138 DOI: 10.1016/j.biortech.2023.129791] [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: 09/17/2023] [Accepted: 09/17/2023] [Indexed: 09/22/2023]
Abstract
This paper investigated the effect of particulate organic matter (POM) on sludge granulation under low organic load. The results showed that POM promoted the formation of aerobic granular sludge (AGS) with a chemical oxygen demand (COD) fraction of 25%, and POM also enhanced the sludge settleability and biomass retention. However, when the COD fraction of POM increased to 50% and 75%, the AGS performance deteriorated. The analysis of extracellular polymeric substances revealed that the POM (accounted for ≤ 50% of COD in the influent) suppressed the secretion of extracellular protein. Analysis of the microbial community showed that species diversity was lower in the POM-fed system, with Rhodocyclaceae being the predominant bacteria responsible for carbon source degradation. Additionally, molecular ecological network analysis demonstrated that when the COD fraction of the POM exceeded 50%, the connectivity and modularity between microbial species decreased, which may explain the sludge performance deterioration.
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Affiliation(s)
- Zhe Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China; Key Lab of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China; Yulin Ecological Environment Monitoring Station, High-tech Zone Xingda Road, Yulin 719000, China.
| | - Rushuo Yang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
| | - Dan Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
| | - Jiaxuan Wang
- School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Yan Ta Road, No. 58, Xi'an 710054, China
| | - Min Gao
- School of Environmental and Chemical Engineering, Xi an Polytechnic University, Jin Hua Nan Road. No.19, Xi'an 710048, China
| | - Aining Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China
| | - Wenlong Liu
- Yulin Ecological Environment Monitoring Station, High-tech Zone Xingda Road, Yulin 719000, China
| | - Yongjun Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an 710055, China; Key Lab of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China
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3
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Tong Y, Lu P, Zhang W, Liu J, Wang Y, Quan L, Ding A. The shock of benzalkonium chloride on aerobic granular sludge system and its microbiological mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 895:165010. [PMID: 37353018 DOI: 10.1016/j.scitotenv.2023.165010] [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: 04/15/2023] [Revised: 06/08/2023] [Accepted: 06/17/2023] [Indexed: 06/25/2023]
Abstract
Quaternary ammonium compounds (QACs) are a kind of biocides and surfactants widely used around the world and wastewater treatment systems were identified as its largest pool. QACs could significantly inhibit microbial activity in biological treatment. Aerobic granular sludge (AGS) is an emerging wastewater biological treatment technology with high efficiency and resistance, but it is still unclear if AGS system could tolerate QACs shock. In this study, a typical QAC (benzalkonium chloride (BACC12)) was selected to investigate its effect on AGS system. Results indicate that BAC could inhibit the pollutants removal performance of AGS system, including COD, NH4+-N and PO43- in the short term and the inhibition ratio had positive correlation with BAC concentration. However, AGS system could gradually adapt to the BAC stress and recover its original performance. BAC shock could destroy AGS structure by decreasing its particle size and finally leading to particle disintegration. Although AGS could secret more EPS to resist the stress, BAC still had significant inhibition on cell activity. Microbial community analysis illustrated that after high BAC concentration shock in short term, Thauera decreased significantly while Flavobacterium became the dominant genus. However, after the performance of AGS system recovered the dominant genus returned to Thauera and relevant denitrifiers Phaeodactylibacter, Nitrosomonas and Pseudofulvimonas also increased. The typical phosphorous removal microorganism Rubrivivax and Leadbetterella also showed the similar trend. The variation of denitrification and phosphorus removal microbial community was consistent with AGS system performance indicating the change of functional microorganism played key role in the AGS response to BAC stress.
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Affiliation(s)
- Yuhao Tong
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Peili Lu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Wenyu Zhang
- Chongqing Three Gorges Water Service Co., Ltd., Chongqing 400020, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Jun Liu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Yuhai Wang
- Sinopec Chongqing Shale Gas Co., Ltd, Chongqing, 408400, China
| | - Lin Quan
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Aqiang Ding
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China.
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4
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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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Liu Z, Yang R, Li Z, Ning F, Wang J, Gao M, Zhang A, Liu Y. Role of cycle duration on the formation of quinoline-degraded aerobic granules in the aspect of sludge characteristics, extracellular polymeric substances and microbial communities. ENVIRONMENTAL RESEARCH 2023; 216:114589. [PMID: 36244442 DOI: 10.1016/j.envres.2022.114589] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/27/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
This study investigated the culture and characteristics of quinoline-degraded aerobic granular sludge (AGS) under 8-h and 12-h cycle duration. According to results, the cultivation of an 8-h cycle duration enhanced the growth of quinoline-degraded AGS, as well as the settleability of sludge and the retention of biomass. Quinoline can be removed from mature AGS at a rate of more than 90%, but it is removed at a rate slightly higher when the AGS are cultured for 12-h. Compared to 12-h cycle duration, 8-h cycle duration result in a greater increase in the production of extracellular polymeric substances, particularly extracellular proteins. In these two systems, Acidovorax and Paracoccus dominated the quinoline degrading bacteria. In addition, analysis by non-metric multidimensional scaling (based on Bray-curtis distance) showed significant differences of community structure between the two reactors. Clostridia and Acidaminobacter are different bacteria with an 8-h cycle duration compared to 12 h. Relative abundance of nitrogen metabolism genes based on PICRUSt2 prediction, which explain the better total nitrogen removal for an 8-h cycle duration compared to a 12-h cycle duration. Finally, the KEGG pathway was analyzed in order to confirm the results of the microbial analysis.
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Affiliation(s)
- Zhe Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China; Key Lab of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Yulin Ecological Environment Monitoring Station, High-tech Zone Xingda Road, Yulin, 719000, China.
| | - Rushuo Yang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Zhengyang Li
- School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Yan Ta Road No. 58, Xi'an, 710054, China
| | - Fangzhi Ning
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Jiaxuan Wang
- School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Yan Ta Road No. 58, Xi'an, 710054, China
| | - Min Gao
- School of Environmental and Chemical Engineering, Xìan Polytechnic University, Jin Hua Nan Road. No.19, Xi'an, 710048, China
| | - Aining Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Yongjun Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China; Key Lab of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an, 710055, China
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6
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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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7
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Jiang Q, Chen H, Fu Z, Fu X, Wang J, Liang Y, Yin H, Yang J, Jiang J, Yang X, Wang H, Liu Z, Su R. Current Progress, Challenges and Perspectives in the Microalgal-Bacterial Aerobic Granular Sludge Process: A Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:13950. [PMID: 36360829 PMCID: PMC9655209 DOI: 10.3390/ijerph192113950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/18/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Traditional wastewater treatment technologies have become increasingly inefficient to meet the needs of low-consumption and sustainable wastewater treatment. Researchers are committed to seeking new wastewater treatment technologies, to reduce the pressure on the environment caused by resource shortages. Recently, a microalgal-bacterial granular sludge (MBGS) technology has attracted widespread attention due to its high efficiency wastewater treatment capacity, low energy consumption, low CO2 emissions, potentially high added values, and resource recovery capabilities. This review focused primarily on the following aspects of microalgal-bacterial granular sludge technology: (1) MBGS culture and maintenance operating parameters, (2) MBGS application in different wastewaters, (3) MBGS additional products: biofuels and bioproducts, (4) MBGS energy saving and consumption reduction: greenhouse gas emission reduction, and (5) challenges and prospects. The information in this review will help us better understand the current progress and future direction of the MBGS technology development. It is expected that this review will provide a sound theoretical basis for the practical applications of a MBGS technology in environmentally sustainable wastewater treatment, resource recovery, and system optimization.
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Affiliation(s)
- Qianrong Jiang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Honglei Chen
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Zeding Fu
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha 410114, China
| | - Xiaohua Fu
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Jiacheng Wang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yingqi Liang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Hailong Yin
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Junbo Yang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Jie Jiang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Xinxin Yang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - He Wang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Zhiming Liu
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA
| | - Rongkui Su
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
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Ferreira Dos Santos A, Amancio Frutuoso FK, de Amorim de Carvalho C, Sousa Aguiar Lira VN, Mendes Barros AR, Bezerra Dos Santos A. Carbon source affects the resource recovery in aerobic granular sludge systems treating wastewater. BIORESOURCE TECHNOLOGY 2022; 357:127355. [PMID: 35609753 DOI: 10.1016/j.biortech.2022.127355] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 05/17/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
This study evaluated the influence of carbon sources on alginate-like exopolymers (ALE) and tryptophan (Trp) biosynthesis in the aerobic granular sludge (AGS). With acetate, the highest biopolymers levels, per gram of volatile suspended solids (VSS) (418.7 mgALE∙g-1 and 4.1 mgTrp∙gVSS-1), were found likely due to biomass loss throughout the operation, which resulted in lower sludge age (4-7 days) and shorter famine period. During granulation, encouraging results on ALE production were obtained with propionate (>250 mgALE∙gVSS-1), significantly higher than those found with glycerol, glucose, and sucrose. Regarding tryptophan production, propionate and glycerol proved to be good substrates, although the content was still lower than acetate (1.6 mgTrp∙gVSS-1). Granules fed with glucose showed the worst results compared to the other substrates (38.5 mgALE∙VSS-1 and 0.6 mgTrp∙gVSS-1) due to the filamentous microorganisms' abundance found. Therefore, this study provides insights to value the production of compounds of industrial interest in AGS systems.
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Affiliation(s)
- Amanda Ferreira Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | - Clara de Amorim de Carvalho
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | | | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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