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Li ZH, Wang RL, Lu M, Wang X, Huang YP, Yang JW, Zhang TY. A novel method for identifying aerobic granular sludge state using sorting, densification and clarification dynamics during the settling process. WATER RESEARCH 2024; 253:121336. [PMID: 38382291 DOI: 10.1016/j.watres.2024.121336] [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: 09/24/2023] [Revised: 01/22/2024] [Accepted: 02/17/2024] [Indexed: 02/23/2024]
Abstract
Aerobic granular sludge is one of the most promising biological wastewater treatment technologies, yet maintaining its stability is still a challenge for its application, and predicting the state of the granules is essential in addressing this issue. This study explored the potential of dynamic texture entropy, derived from settling images, as a predictive tool for the state of granular sludge. Three processes, traditional thickening, often overlooked clarification, and innovative particle sorting, were used to capture the complexity and diversity of granules. It was found that rapid sorting during settling indicates stable granules, which helps to identify the state of granules. Furthermore, a relationship between sorting time and granule heterogeneity was identified, helping to adjust selection pressure. Features of the dynamic texture entropy well correlated with the respirogram, i.e., R2 were 0.86 and 0.91 for the specific endogenous respiration rate (SOURe) and the specific quasi-endogenous respiration rate (SOURq), respectively, providing a biologically based approach for monitoring the state of granules. The classification accuracy of models using features of dynamic texture entropy as an input was greater than 0.90, significantly higher than the input of conventional features, demonstrating the significant advantage of this approach. These findings contributed to developing robust monitoring tools that facilitate the maintenance of stable granular sludge operations.
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Affiliation(s)
- Zhi-Hua 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Ruo-Lan 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; Xi'an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Meng Lu
- 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xin 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; Xi'an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yong-Peng Huang
- 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Jia-Wei Yang
- 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tian-Yu Zhang
- Department of Mathematical Sciences, Montana State University, Bozeman, MT 59717, USA
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2
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Qu Z, Tan C, Wang X, Zhao N, Li J. Deciphering performance and microbial characterization of marine anammox bacteria-based consortia treating nitrogen-laden hypersaline wastewater: Inhibiting threshold of salinity. BIORESOURCE TECHNOLOGY 2024; 393:130170. [PMID: 38072078 DOI: 10.1016/j.biortech.2023.130170] [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: 10/11/2023] [Revised: 12/04/2023] [Accepted: 12/05/2023] [Indexed: 01/18/2024]
Abstract
Hypersaline wastewater posed a challenge to microbial nitrogen removal processes. Herein, halophilic marine anammox bacteria (MAB) were applied to treat nitrogen-rich wastewater with 35-90 g/L salts for the first time. It was found that MAB, with low relative abundance (2.3-6.9 %), still exhibited good nitrogen removal efficiency (>90 %) under 35-70 g/L salts. The specific anammox activity peaked at 180.16 mg N/(g·VSS·d) at 65 g/L salts. MAB secreted more extracellular polymeric substances to resist the adverse effects of hypersaline stress. Nevertheless, the nitrogen removal deteriorated at 75 g/L salts, and further collapsed as the salinity increased. At 90 g/L salts, total nitrogen removal rate decreased by 74 % compared with that of 35 g/L salts. Besides, SBR1031 increased from 12.0 % (35 g/L salts) to 17.4 % (90 g/L salts) and became the dominant bacterial genus in the reactor. This work shed light on the treatment of hypersaline wastewater through MAB.
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Affiliation(s)
- Zhaopeng Qu
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Chen Tan
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Xiaocui Wang
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Na Zhao
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Jin Li
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China.
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3
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Huang YP, Wang X, Wang RL, He JT, Huang Y, Hang ZY, Chen X, Li ZH. Managing stability of aerobic granules by coordinating diameter and denitrification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167795. [PMID: 37838046 DOI: 10.1016/j.scitotenv.2023.167795] [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: 08/08/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023]
Abstract
Aerobic Granular Sludge (AGS) technology is a promising solution for wastewater treatment due to its structure and high biomass retention capacity. However, the stability of AGS is still a challenge for widespread use. This study investigated the relationships among granule stability, granule diameter, biomass retention capacity, and denitrification efficiency. The results showed that granule diameter did not necessarily indicate granule stability, nor was it associated with biomass retention capacity. For mature granules, promoting simultaneous nitrification and denitrification rather than anoxic denitrification was found to improve granule stability. The deterioration of clarification capacity caused by increased anoxic denitrification at high nitrate concentration was not indicated by diameters or the commonly used SVI5/SVI30. Therefore, ensuring coordination between diameter and denitrification control is crucial for the stability of AGS. These results provide a basis for further research and development of efficient and user-friendly methods for monitoring granular stability.
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Affiliation(s)
- Yong-Peng Huang
- 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xin 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; Xi'an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Ruo-Lan 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; Xi'an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Jin-Tao 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; Xi'an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yuan Huang
- 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhen-Yu 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; Xi'an Key Laboratory of Intelligent Equipment Technology for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xi Chen
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Xi'an 710048, China
| | - Zhi-Hua 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 for Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
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4
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Sun Z, Zhang J, Wang J, Zhu H, Xiong J, Nong G, Luo M, Wang J. Direct start-up of aerobic granular sludge system with dewatered sludge granular particles as inoculant. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 326:116540. [PMID: 36427360 DOI: 10.1016/j.jenvman.2022.116540] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
Aerobic granular sludge (AGS) is a promising technology for engineering applications in the biological treatment of sewage. New objective is to skip the conventional granulation step to integrate it into a continuous-flow reactor directly. This study proposed a method for integrating spherical pelletizing granular sludge (SPGS) into a new patented aerobic granular sludge bed (AGSB), a continuous up-flow reactor. AGSB system could be startup directly, and after 120 days of operation, the SPGS maintained a relatively intact spherical structure and stability. With an initial high chemical oxygen demand (COD) volume loading of over 2.0 kg/(m3·d), this system achieved the desired effect as the same as a mature AGS system. The final mixed liquid suspended solids, and the ratio of 30 min-5 min sludge volume index (SVI30/SVI5) were 20,000 mg/L, and 0.84, respectively. Although hydraulic elution and filamentous bacteria (FBs) had a slightly negative impact on initial phase pollutant removal, the final removal rates for COD, total nitrogen (TN), ammonia nitrogen (NH4+-H), and total phosphorus (TP) were 90%, 70%, 95%, and 85%, respectively. The presence of specific functional microorganisms promoted the secretion of extracellular polymeric substances (EPS), from 90.65 to 209.78 mg/gVSS. The maturation process of SPGS altered the microbial community structures and reduced the species abundance of microbes in sludge.
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Affiliation(s)
- Zhuo Sun
- School of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China; Branch Graduate School of Guangxi Bossco Environmental Protection Technology Co., Ltd, Guangxi University, Nanning, 530007, People's Republic of China
| | - Jiaming Zhang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, People's Republic of China
| | - Jin Wang
- Department of Landscape Architecture, School of Design, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
| | - Hongxiang Zhu
- School of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, People's Republic of China.
| | - Jianhua Xiong
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, People's Republic of China
| | - Guoyou Nong
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, People's Republic of China
| | - Mengqi Luo
- Guangxi Bossco Environmental Protection Technology Co., Ltd., Nanning, 530007, People's Republic of China
| | - Jue Wang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, People's Republic of China
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5
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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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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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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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8
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Liang D, Guo W, Li D, Ding F, Li P, Zheng Z, Li J. Enhanced aerobic granulation for treating low-strength wastewater in an anaerobic-aerobic-anoxic sequencing batch reactor by selecting slow-growing organisms and adding carriers. ENVIRONMENTAL RESEARCH 2022; 205:112547. [PMID: 34902378 DOI: 10.1016/j.envres.2021.112547] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/12/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
The aerobic granular sludge (AGS) process is a promising technology for wastewater treatment. However, a long start-up period for granulation and instability during long-term operation still hinder the application of AGS technology, especially for low-strength wastewater. To solve these two problems, this study tested a novel strategy involving the selection of slow-growing organisms and the addition of carriers in an anaerobic-aerobic-anoxic sequencing batch reactor (AN/O/AX_SBR). Three identical AN/O/AX_SBRs (R_Ctrl, R_CCM, and R_GAC), fed with low-strength wastewater, were operated for 120 days. R_Ctrl had no carriers, R_CCM contained cell culture microcarriers (CCM), and R_GAC contained granular activated carbon (GAC). Mature AGS was achieved within 80 days in all reactors. The carriers could reduce the maturation period of AGS by approximately 10 days (76, 66, and 69 days in R_Ctrl, R_CCM, and R_GAC, respectively) and improve the physical strength of the AGS. AGS showed a strong structure without excessive proliferation of filamentous bacteria, full-grown size (900-1100 μm), and good settleability (SVI5 was 15.4-19.4 mL/g). Microbiological analysis showed that AN/O/AX_SBRs can provide a metabolic selective pressure to select slow-growing organisms such as nitrifying bacteria (norank_f__NS9_marine_group, Ellin6067, and Nitrospira), glycogen and phosphorus accumulating organisms (GAOs: Candidatus_Competibacter and Defluviicoccus; PAOs: Candidatus_Accumulibacter and Flavobacterium). All reactors showed good performance for simultaneous nitrification, endogenous denitrification, and phosphorus removal. The removal efficiencies of total nitrogen and total phosphorous were above 70% and 80%, respectively. The cycle test showed intermediate PAO-GAO metabolism prevailed in the system, and endogenous denitrification was primarily carried out by denitrifying GAOs.
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Affiliation(s)
- Dongbo Liang
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Wei Guo
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Dongyue Li
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Fan Ding
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Peilin Li
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Zhaoming Zheng
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Jun Li
- Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China.
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9
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Zhang C, Gao F, Wu Y, Xu G, Liu H, Zhang H, Yang F, Xu Y. Small-sized salt-tolerant denitrifying and phosphorus removal aerobic granular sludge cultivated with mariculture waste solids to treat synthetic mariculture wastewater. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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10
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He Q, Xie Z, Tang M, Fu Z, Ma J, Wang H, Zhang W, Zhang H, Wang M, Hu J, Xu P. Insights into the simultaneous nitrification, denitrification and phosphorus removal process for in situ sludge reduction and potential phosphorus recovery. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 801:149569. [PMID: 34416609 DOI: 10.1016/j.scitotenv.2021.149569] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/06/2021] [Accepted: 08/06/2021] [Indexed: 06/13/2023]
Abstract
A simultaneous nitrification-denitrification and phosphorus removal (SNDPR) system operated in an alternating anaerobic/aerobic/anoxic (A/O/A) mode was revisited from new perspectives of sludge reduction and potential phosphorus recovery. Reliable and robust removal performance was obtained even under winter temperatures, with average removal efficiency of COD, TP, NH4+-N and TIN being 89.68%, 93.60%, 92.15% and 79.01% at steady state, respectively. Inoculated sludge got enhanced in biomass density, settleability, and bioactivity. And relatively stable amounts of extracellular polymeric substances (EPS) with a stable protein/ polysaccharide (PN/PS) ratio were observed over operation. Meanwhile, a low observed sludge yield (Yobs) of 0.083 g MLSS/g COD (0.082 g MLVSS/g COD) was obtained. A maximum anaerobic phosphorus release up to 43.54 mg/L was found, thus providing phosphorus-rich and low-turbidity stream for further phosphorus recovery. Overall, the SNDPR system deserved attention for in situ sludge reduction and potential phosphorus recovery, beyond reliable and stable wastewater treatment.
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Affiliation(s)
- 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
| | - 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
| | - Meiyi Tang
- China West Construction Hunan Group Co., Ltd., Changsha 410114, 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
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Wei Zhang
- School of Hydraulic Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Huining Zhang
- School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Meng Wang
- Jinan Municipal Engineering Design & Research Institute (Group) Co., Ltd., Jinan 250003, China
| | - Junxian Hu
- School of Metallurgy and Environment, Central South University, Changsha 410083, China.
| | - 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.
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11
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Hang Z, Li Z, Zhu Y, Zhang J, Yang F, Zhang T. A new approach to evaluate and improve the stability of aerobic sludge systems based on maintenance coefficient. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113192. [PMID: 34252857 DOI: 10.1016/j.jenvman.2021.113192] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 05/31/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
Stability is a key issue of wastewater treatment plants using either aerobic granular (AGS) or conventional activated sludge (CAS). The two forms of aerobic sludge were cultivated under different conditions to study the main factors affecting their stability. It was found that maintenance coefficient (m) describing the fraction of non-growth energy of granules increased significantly when the system became more stable during processes with the enhancement of granulation and the periodic short-term shock load. The yield coefficient (YH) was the main factor affecting the m value, and the inhibition in YH value was able to promote the maintenance potential according to the kinetic equation. Therefore, strategies that promote the maintenance coefficient could be applied to improve the stability of sludge systems, including inhibiting the yield rate and taking periodic short-term shock. Evaluation of stability based on the maintenance coefficient is a promising tool for ensuring the stable operation of wastewater treatment processes.
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Affiliation(s)
- Zhenyu Hang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Zhihua Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
| | - Yuanmo Zhu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Jing Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Fan Yang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Tianyu Zhang
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, 59717-2400, USA
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12
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Guzmán-Fierro V, Sanhueza J, Arriagada C, Pereira L, Campos V, Gallardo JJ, Roeckel M. The prediction of partial-nitrification-anammox performance in real industrial wastewater based on granular size. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 286:112255. [PMID: 33647672 DOI: 10.1016/j.jenvman.2021.112255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 12/28/2020] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
To date, the partial nitrification-Anammox (PN-A) granular sludge size has been exclusively analyzed in synthetic substrates. In this work, different ranges of granular size of PN-A sludge were studied at low oxygen concentration using real industrial wastewater as, well as a synthetic substrate. The granular sludge was characterized by the specific nitrification activity (SNA), specific anammox activity (SAA), and granule sedimentation rate. The relative abundance of the bacterial consortium was assessed for each range of diameters through the fluorescence in situ hybridization (FISH) technique. SNA exhibits a direct association with the specific surface of granules, which proves the importance of the outer layer in the nitrification process. Even more critical, the flocculent sludge allowed the stability of the nitrifying activity. The SAA showed different performances faced the real industrial and synthetic substrates. With the synthetic substrate, the SAA decreased at higher diameter ranges, whereas with the industrial substrate, the SAA increased at higher diameter ranges. This situation is explained by the oxygen protection in the sludge maintained with industrial wastewater. The relative abundance of heterotrophic bacteria increased from 9.6 to 22%, due to the presence of organic matter in the industrial substrate. The granular sedimentation rate increased with the diameter of the granules with a linear correlation (R2 > 0.98). Thus, granular sizes can be selected through sedimentation rate control. A linear correlation between SAA and granular sludge diameter ranges was observed. With this correlation, an error of less than 11% in the prediction of SAA was achieved. The use of diameter measurement and granular sedimentation rate as routine techniques could contribute to the control and start-up of PN-A reactors. In the same sense, organic matter present in defined concentrations, can be beneficial for the granular sludge stability, and thus, for nitrogen removal.
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Affiliation(s)
- Víctor Guzmán-Fierro
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepción, Chile
| | - José Sanhueza
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepción, Chile
| | - Constanza Arriagada
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepción, Chile
| | - Luis Pereira
- Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Víctor Campos
- Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Juan José Gallardo
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepción, Chile; Department of Chemical Engineering, Higher Engineering School, University of Almería, Spain
| | - Marlene Roeckel
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepción, Chile.
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13
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Wang L, Zhan H, Wu G, Zeng Y. Effect of operational strategies on the rapid start-up of nitrogen removal aerobic granular system with dewatered sludge as inoculant. BIORESOURCE TECHNOLOGY 2020; 315:123816. [PMID: 32688252 DOI: 10.1016/j.biortech.2020.123816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/03/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
In both sequencing batch reactors with dewatering sludge as inoculant, the strategies by step-feeding (R1) or step-feeding combined with low aeration (R2) were performed under alternating anoxic/aerobic condition to discover superior methods launching nitrogen removal aerobic granule system. Interestingly, two reactors accomplished granulation at day 0, two days later, possessed prominent settling performance (SVI < 45 ml/g. MLSS) and denitrifying ability (TIN > 80%). Thereinto, R2 had lower crushing rate, larger granules, higher biomass and better pollutant removal performance owing to low aeration and more filamentous bacteria on AGS surface. Moreover, effluent NH4+-N was used as indicator of excess filaments due to its quick response for the filaments. After effluent NH4+-N exceeded 5 mg/L, causative filaments Sphaerotilus were effectively inhibited and eliminated by enhancing pH value to 8.0 ± 0.2. As a result, this study provides a new insight into rapid start-up nitrogen removal granule system by promoting and limiting filaments in proper period.
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Affiliation(s)
- Lei Wang
- School of Civil Engineering, Southwest Jiaotong University, 610031 Chengdu, China; School of Environment Science and Spatial Informatics, China University of Mining and Technology, 221116 Xuzhou, China.
| | - Hanhui Zhan
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, 221116 Xuzhou, China
| | - Gang Wu
- School of Life Science and Engineering, Southwest Jiaotong University, 610031 Chengdu, China
| | - Yong Zeng
- School of Civil Engineering, Southwest Jiaotong University, 610031 Chengdu, China
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14
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Rezvani F, Sarrafzadeh MH. Autotrophic granulation of hydrogen consumer denitrifiers and microalgae for nitrate removal from drinking water resources at different hydraulic retention times. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 268:110674. [PMID: 32383647 DOI: 10.1016/j.jenvman.2020.110674] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 03/27/2020] [Accepted: 04/28/2020] [Indexed: 06/11/2023]
Abstract
To avoid hydrogen injection and to enhance the settleability of microbial biomass in biological treatment of nitrate-contaminated drinking water resources, a new method based on granulation of a mixture of hydrogen consumer denitrifiers (HCD) and microalgae is introduced. Decreasing hydraulic retention time (HRT) was applied as the selection pressure in an up-flow photobioreactor to increase the speed of granulation and nitrate removal under autotrophic condition during a 50-day operation. Formation of granules occurred at three phases including granule nucleation, growth of granule, and mature granule, with decreasing the values of ζ-potential from -19 mV to -4 mV. Enhancement of microbial attachment within granule formation could reduce the presence of total suspended solids in the effluent. Developed granules of HCD and microalgae could settle down with velocity of 40 ± 0.6 m/h when reaching the average size of 1.2 mm at day 40. Complete NO3--N removal from drinking water was achieved from the initial stage of granulation until the end of operation at all HRTs of 3 days-5 h. The clear treated water was obtained at the growth phase when the chemical oxygen demand and phosphate were undetectable. Therefore, the application of HCD-microalgae granule is a promising way for nitrate removal from water.
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Affiliation(s)
- Fariba Rezvani
- UNESCO Chair on Water Reuse, Biotechnology Group, School of Chemical Engineering, College of Engineering, University of Tehran, Iran
| | - Mohammad-Hossein Sarrafzadeh
- UNESCO Chair on Water Reuse, Biotechnology Group, School of Chemical Engineering, College of Engineering, University of Tehran, Iran.
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15
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Bekele ZA, Delgado Vela J, Bott CB, Love NG. Sensor-mediated granular sludge reactor for nitrogen removal and reduced aeration demand using a dilute wastewater. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:1006-1016. [PMID: 31954086 PMCID: PMC7383604 DOI: 10.1002/wer.1296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 12/26/2019] [Accepted: 01/12/2020] [Indexed: 06/10/2023]
Abstract
A sensor-mediated strategy was applied to a laboratory-scale granular sludge reactor (GSR) to demonstrate that energy-efficient inorganic nitrogen removal is possible with a dilute mainstream wastewater. The GSR was fed a dilute wastewater designed to simulate an A-stage mainstream anaerobic treatment process. DO, pH, and ammonia/nitrate sensors measured water quality as part of a real-time control strategy that resulted in low-energy nitrogen removal. At a low COD (0.2 kg m-3 day-1 ) and ammonia (0.1 kg-N m-3 day-1 ) load, the average degree of ammonia oxidation was 86.2 ± 3.2% and total inorganic nitrogen removal was 56.7 ± 2.9% over the entire reactor operation. Aeration was controlled using a DO setpoint, with and without residual ammonia control. Under both strategies, maintaining a low bulk oxygen level (0.5 mg/L) and alternating aerobic/anoxic cycles resulted in a higher level of nitrite accumulation and supported shortcut inorganic nitrogen removal by suppressing nitrite oxidizing bacteria. Furthermore, coupling a DO setpoint aeration strategy with residual ammonia control resulted in more stable nitritation and improved aeration efficiency. The results show that sensor-mediated controls, especially coupled with a DO setpoint and residual ammonia controls, are beneficial for maintaining stable aerobic granular sludge. PRACTITIONER POINTS: Tight sensor-mediated aeration control is need for better PN/A. Low DO intermittent aeration with minimum ammonium residual results in a stable N removal. Low DO aeration results in a stable NOB suppression. Using sensor-mediated aeration control in a granular sludge reactor reduces aeration cost.
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Affiliation(s)
- Zerihun A. Bekele
- Department of Civil and Environmental EngineeringUniversity of MichiganAnn ArborMichigan
| | - Jeseth Delgado Vela
- Department of Civil and Environmental EngineeringHoward UniversityWashingtonDistrict of Columbia
| | | | - Nancy G. Love
- Department of Civil and Environmental EngineeringUniversity of MichiganAnn ArborMichigan
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16
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Zhang G, Shi Y, Zhang H, Yang F, Cai L. Operation adjustments of an electrochemically coupled system for total nitrogen removal and the associated mechanism. CHEMOSPHERE 2020; 246:125649. [PMID: 31918076 DOI: 10.1016/j.chemosphere.2019.125649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 09/13/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
A coupled system consisting of sequencing batch reactor and microbial fuel cell (SBR-MFC) was designed to buffer pH drift and purify wastewater. The addition of nitrifying sludge and the adjustment of hydraulic retention time (HRT) were performed to achieve better removal of total nitrogen (TN). When anaerobic/aerobic/anoxic phases in one cycle were 6/4/2 h, the removal efficiency of ammonium was 99.0 ± 1.3%, whereas denitrification was insufficient and the overall removal efficiency of TN was only 29.1 ± 5.8%. When the phases were adjusted to 6/2/4 h, the removal efficiencies of ammonium were 100.0 ± 0.0% in both closed and open circuits, and the overall removal efficiencies of TN were 91.4 ± 0.2% and 71.7 ± 4.2%, respectively, improved by 20% in MFC mode; the maximum voltage (200 Ω) maintained at 0.1 V. Ammonium-oxidizing bacteria (AOB) and Nitrite-oxidizing bacteria (NOB) in the sludge carried out nitrification. The main denitrification pathways in anoxic phase involved polyhydroxyalkanoate (PHA) denitrification by denitrifying glycogen accumulating organisms (GAOs) and electrochemical denitrification by electrochemical active bacteria (EAB). Few polyphosphate accumulating organisms (PAOs) were present, which accounted for poor P removal.
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Affiliation(s)
- Guangyi Zhang
- School of Water Conservancy Engineering, Zhengzhou University, Kexue Road 100, Zhengzhou, 450001, China; Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China
| | - Yinghao Shi
- School of Water Conservancy Engineering, Zhengzhou University, Kexue Road 100, Zhengzhou, 450001, China
| | - Hanmin Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China.
| | - Fenglin Yang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China
| | - Lu Cai
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China
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17
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Xu J, Pang H, He J, Nan J. The effect of supporting matrix on sludge granulation under low hydraulic shear force: Performance, microbial community dynamics and microorganisms migration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 712:136562. [PMID: 32050387 DOI: 10.1016/j.scitotenv.2020.136562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/12/2019] [Accepted: 01/04/2020] [Indexed: 06/10/2023]
Abstract
Granular sludge usually takes extracellular polymers (EPS) as matrices for colonizing microorganisms and maintaining structural stability. However, the low strength of EPS threatens the disintegration of granules, especially under low hydraulic shear force. To accelerate the formation and enhance the stability of granules, micro-sized melamine (ME) sponges (RA) and polyurethane (PU) sponges (RB) were screened out as matrix substitutes for developing aerobic granular biofilm (AGB) in this study. The superficial gas velocity was 0.8 cm s-1. Both reactors achieved over 95% ammonium nitrogen removal efficiency within 10 days. During stabilization period, the chemical oxygen demand, total nitrogen and total phosphorus removal efficiencies were 90.5%, 70% and 95% in RA and 87.8%, 83% and 88% in RB, respectively. Confocal laser scanning microscopy (CLSM) detection revealed that β-polysaccharide was more concentrated in the outer layer in PU-AGB but uniformly dispersed in ME-AGB. The denitrifying phosphorus accumulating organisms (Flavobacterium) was dominant in RA, while the denitrifying glycogen accumulating organisms (Candidatus_Competibacter) was dominant in RB. Fluorescence in situ hybridization (FISH) analysis indicated that the microbial distribution in ME-AGB was relatively uniform, while there was a significant migration of functional microorganisms in PU-AGB. The super-hydrophilicity of ME and the high hydrophobicity of PU may be the main reasons for these differences. Overall, this study indicated that ME sponge is a more suitable material for supporting AGB than PU sponge.
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Affiliation(s)
- Jie Xu
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Heliang Pang
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China.
| | - Junguo He
- Guangzhou University, Guangzhou 510006, China
| | - Jun Nan
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China
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18
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Leal C, Val del Río A, Mesquita DP, Amaral AL, Castro PM, Ferreira EC. Sludge volume index and suspended solids estimation of mature aerobic granular sludge by quantitative image analysis and chemometric tools. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2019.116049] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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19
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Rollemberg SLDS, Ferreira TJT, Firmino PIM, Dos Santos AB. Impact of cycle type on aerobic granular sludge formation, stability, removal mechanisms and system performance. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 256:109970. [PMID: 31989985 DOI: 10.1016/j.jenvman.2019.109970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 11/11/2019] [Accepted: 12/06/2019] [Indexed: 06/10/2023]
Abstract
This paper aimed to assess the impact of the cycle type on aerobic granular sludge (AGS) formation, stability and system performance. Six AGS reactors were operated either on A/O cycles (anaerobic followed by oxic phase) or A/O/A cycles (anaerobic, followed by oxic and anoxic phases), changing only the phase time distribution. Reactors with high percentage of aerobic phase (65% of the total cycle time) generated granules with better settleability and resistance, however denitrification was impaired. On the other hand, reactors with long anaerobic or anoxic phases presented excellent nutrients removals, but the granules were fluffy and unstable. The best results in terms of performance and stability were achieved in an A/O/A reactor with short anoxic phase (10% of the total cycle) and medium aerobic phase (55% of the total cycle). Therefore, in AGS reactors, it is indispensable to optimize the cycle, aiming at fast biomass formation, long-term granule stability and high-rate pollutants removal.
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Affiliation(s)
| | | | - Paulo Igor Milen Firmino
- 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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20
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Xu J, Pang H, He J, Nan J, Wang M, Li L. Start-up of aerobic granular biofilm at low temperature: Performance and microbial community dynamics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 698:134311. [PMID: 31783455 DOI: 10.1016/j.scitotenv.2019.134311] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 09/04/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
Low temperature is a great challenge for the biological treatment of wastewater. In this study, the rapid start-up of aerobic granular biofilm (AGF) reactor was realized by adding micro-sized polyurethane (PU) sponges as matrices at 10 °C. The results showed that the granulation process of AGF was different from that of traditional aerobic granular sludge and biofilms, which was formed by using the sludge intercepted in PU matrix instead of sponge skeletons as granulation carriers. During the 5-month operation period, stable pollutants removal performance was achieved within 70 days, besides, the corresponding ammonium, total nitrogen, and total phosphorus removal efficiencies were 98%, 70%, and 95%, respectively. The addition of PU matrices inhibited the growth of filamentous bacteria and provided support for high structural stability of AGF. With the operation of the reactor, the relative abundance of traditional denitrifying bacteria (genera Thauera and Acidovorax, etc.) decreased gradually, and the putative denitrifying phosphorus accumulating genus, Dechloromonas, occupied a dominant position in the system. This experiment showed that AGF system could be successfully started-up and operated with efficient pollutants removal performance under low temperature when using micro-sized PU sponges as matrices.
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Affiliation(s)
- Jie Xu
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China.
| | - Heliang Pang
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Junguo He
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, China
| | - Jun Nan
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Mengfei Wang
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Lin Li
- School of Environment, Harbin Institute of Technology (HIT), Harbin 150090, China
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21
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Ai C, Yan Z, Zhou H, Hou S, Chai L, Qiu G, Zeng W. Metagenomic Insights into the Effects of Seasonal Temperature Variation on the Activities of Activated Sludge. Microorganisms 2019; 7:E713. [PMID: 31861224 PMCID: PMC6956059 DOI: 10.3390/microorganisms7120713] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 12/13/2019] [Accepted: 12/13/2019] [Indexed: 01/09/2023] Open
Abstract
It is well acknowledged that the activities of activated sludge (AS) are influenced by seasonal temperature variation. However, the underlying mechanisms remain largely unknown. Here, the activities of activated sludge under three simulated temperature variation trends were compared in lab-scale. The TN, HN3-H, and COD removal activities of activated sludge were improved as temperature elevated from 20 °C to 35 °C. While, the TN, HN3-H, COD and total phosphorus removal activities of activated sludge were inhibited as temperature declined from 20 °C to 5 °C. Both the extracellular polymer substances (EPS) composition (e.g., total amount, PS, PN and DNA) and sludge index of activated sludge were altered by simulated seasonal temperature variation. The variation of microbial community structures and the functional potentials of activated sludge were further explored by metagenomics. Proteobacteria, Actinobacteria, Acidobacteria and Bacteroidetes were the dominant phyla for each activated sludge sample under different temperatures. However, the predominant genera of activated sludge were significantly modulated by simulated temperature variation. The functional genes encoding enzymes for nitrogen metabolism in microorganisms were analyzed. The enzyme genes related to ammonification had the highest abundance despite the changing temperature, especially for gene encoding glutamine synthetase. With the temperature raising from 20 °C to 35 °C. The abundance of amoCAB genes encoding ammonia monooxygenase (EC:1.14.99.39) increased by 305.8%. Meanwhile, all the enzyme genes associate with denitrification were reduced. As the temperature declined from 20 °C to 5 °C, the abundance of enzyme genes related to nitrogen metabolism were raised except for carbamate kinase (EC:2.7.2.2), glutamate dehydrogenase (EC:1.4.1.3), glutamine synthetase (EC:6.3.1.2). Metagenomic data indicate that succession of the dominant genera in microbial community structure is, to some extent, beneficial to maintain the functional stability of activated sludge under the temperature variation within a certain temperature range. This study provides novel insights into the effects of seasonal temperature variation on the activities of activated sludge.
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Affiliation(s)
- Chenbing Ai
- School of Metallurgy and Environment, Central South University, Changsha 410083, China; (C.A.)
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
- Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Zhang Yan
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou 350007, China
| | - Han Zhou
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Shanshan Hou
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Liyuan Chai
- School of Metallurgy and Environment, Central South University, Changsha 410083, China; (C.A.)
- Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, China
| | - Guanzhou Qiu
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Weimin Zeng
- School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China
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22
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Zhang L, Long B, Wu J, Cheng Y, Zhang B, Zeng Y, Huang S, Zeng M. Evolution of microbial community during dry storage and recovery of aerobic granular sludge. Heliyon 2019; 5:e03023. [PMID: 31890963 PMCID: PMC6926229 DOI: 10.1016/j.heliyon.2019.e03023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/18/2019] [Accepted: 12/06/2019] [Indexed: 12/15/2022] Open
Abstract
Aerobic granular sludge (AGS) was imbedded in agar and stored at 4 °C for 30 days, and then the stored granules were recovered in a sequencing batch reactor fed real wastewater within 11 days. Variations in microbial community compositions were investigated during dry storage and recovery of AGS, aiming to elucidate the mechanism of granular stability loss and recovery. The storage and recovery of AGS involved microbial community evolution. The dominant bacterial genera of the mature AGS were Zoogloea (relative abundance of 22.39%), Thauera (16.03%) and Clostridium_sensu_stricto (11.17%), and those of the stored granules were Acidovorax (26.79%), Macellibacteroides (12.83%) and Pseudoxanthomonas (5.69%), respectively. However, the dominant genera were Streptococcus (43.64%), Clostridium_sensu_stricto (12.3.6%) and Lactococcus (11.47%) in the recovered AGS. Methanogens were always the dominant archaeal species in mature AGS (93.01%), stored granules (99.99%) and the recovered AGS (94.84%). Facultative anaerobes and anaerobes proliferated and dominated in the stored granules, and their metabolic activities gradually led to granular structure destruction and property deterioration. However, the stored granules served as carriers for the microbes originated from the real septic tank wastewater during recovery. They proliferated rapidly and secreted a large number of extracellular polymeric substances which helped to recover the granular structure in 11 days.
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Affiliation(s)
- Linan Zhang
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
| | - Bei Long
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
| | - Junfeng Wu
- Henan Province Key Laboratory of Water Pollution Control and Rehabilitation Technology, Mingyue Road, Pingdingshan, 467036, Henan, China
| | - Yuanyuan Cheng
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
| | - Binchao Zhang
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
| | - Yu Zeng
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
| | - Sinong Huang
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
| | - Mingjing Zeng
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave. 86, Ganzhou, 341000, Jiangxi, China
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23
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Li ZH, Zhu YM, Zhang YL, Zhang YR, He CB, Yang CJ. Characterization of aerobic granular sludge of different sizes for nitrogen and phosphorus removal. ENVIRONMENTAL TECHNOLOGY 2019; 40:3622-3631. [PMID: 29855222 DOI: 10.1080/09593330.2018.1483971] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 05/27/2018] [Indexed: 06/08/2023]
Abstract
Granular size plays a key role in the performance of the aerobic granular sludge (AGS). As the diameter of the granule increases, stratification may begin to appear due to the increase in mass transfer resistance. Aerobic granules harvested from a lab-scale anaerobic-aerobic sequencing batch reactor (AO-SBR) were classified into three categories according to their size: (a) 0.15-0.28 mm, (b) 0.28-0.45 mm and (c) larger than 0.45 mm. In this study, the categories were called small-size, medium-size and large-size granules, respectively. A fraction of the different forms of phosphate and denitrification efficiency was investigated in each category. Results show that small-size granules present much more easily mobile phosphorus than other granules. Moreover, the denitrification performance has been tested by using dumping and trickling patterns for COD and NO3--N feeding. The results demonstrated that the large-size granules exhibit poor denitrification rates, as opposed to the medium-size granules. Therefore, medium-size granules, with a size of 0.28-0.45 mm, are regarded as the most suitable granular size for AGS in this experiment from the perspective of denitrification and phosphorus removal.
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Affiliation(s)
- Zhi-Hua Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, School of Environmental & Municipal Engineering, Xi'an University of Architecture and Technology , Xi'an , People's Republic of China
| | - Yuan-Mo Zhu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, School of Environmental & Municipal Engineering, Xi'an University of Architecture and Technology , Xi'an , People's Republic of China
| | - Ya-Li Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, School of Environmental & Municipal Engineering, Xi'an University of Architecture and Technology , Xi'an , People's Republic of China
| | - Yu-Rong Zhang
- School of Civil Engineering, Lanzhou University of Technology , Lanzhou , People's Republic of China
| | - Chun-Bo He
- Department of Civil and Environmental Engineering, Norwegian University of Science and Technology , Trondheim , Norway
| | - Cheng-Jian Yang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, School of Environmental & Municipal Engineering, Xi'an University of Architecture and Technology , Xi'an , People's Republic of China
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Wang L, Zhan H, Wang Q, Wu G, Cui D. Enhanced aerobic granulation by inoculating dewatered activated sludge under short settling time in a sequencing batch reactor. BIORESOURCE TECHNOLOGY 2019; 286:121386. [PMID: 31078075 DOI: 10.1016/j.biortech.2019.121386] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/24/2019] [Accepted: 04/27/2019] [Indexed: 05/06/2023]
Abstract
The effect of dewatered activated sludge on aerobic granulation was investigated in a sequencing batch reactor (SBR) under short settling time. The results showed that dewatered sludge accelerated aerobic granulation and the granulation was completed within 5 days. On day 5, the aerobic granules were regular, compact, fast-settling and high granular strength and possessed excellent removal performance of carbon and nitrogen. The change trend of extracellular polymeric substances (EPS) was basically consistent with granular strength and granulation rate, indicating that EPS in granules played a vital function for granulation. Microbial community succession was investigated by pyrosequencing. In 5 days, microbial diversity was reduced and certain strains were rapidly enriched in the granules to become dominant species, serving on a crucial role in rapid granulation and pollutant removal as they could secrete excess EPS and possess the excellentability removing carbon and nitrogen pollutants.
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Affiliation(s)
- Lei Wang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, 221116 Xuzhou, China; School of Civil Engineering, Southwest Jiaotong University, 610031 Chengdu, China
| | - Hanhui Zhan
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, 221116 Xuzhou, China.
| | - Qingqing Wang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, 221116 Xuzhou, China
| | - Gang Wu
- School of Life Science and Engineering, Southwest Jiaotong University, 610031 Chengdu, China
| | - Dabin Cui
- School of Mechanical Engineering, Southwest Jiaotong University, 610031 Chengdu, China
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25
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Long B, Xuan X, Yang C, Zhang L, Cheng Y, Wang J. Stability of aerobic granular sludge in a pilot scale sequencing batch reactor enhanced by granular particle size control. CHEMOSPHERE 2019; 225:460-469. [PMID: 30889409 DOI: 10.1016/j.chemosphere.2019.03.048] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/22/2019] [Accepted: 03/09/2019] [Indexed: 06/09/2023]
Abstract
Aerobic granulation was successfully achieved in a pilot scale sequencing batch reactor within 40 days. Then, stability of different particle size granules was explored according to their activity and resistance to ultrasonic crushing. Different particle size granules (0.3-0.6 mm, 0.6-1 mm, 1-1.43 mm, 1.43-2 mm, 2-3 mm and 3-4 mm) were exposed under different ultrasonic power separately. It was found that the granules with 2-3 mm always had the maximum granulation rates after ultrasonic crushing. Meanwhile, activity data showed that the 2-3 mm granules had the lowest specific oxygen utilization rates, which indicated that they were easier to maintain stability as the increase of their particle sizes was the slowest. So, 500 mL mixed liquid of the reactor were taken out and sieved to obtain the 2-3 mm granules, which were subsequently returned to the reactor to increase their proportion. Through the manual regulation, the proportion of 2-3 mm granules kept increasing which gradually became dominant in the reactor. Under the strategy of 86 days of operation, the aerobic granules were regular and compact, which had good removal effects of the real wastewater. The results indicated that the stability of the system could be greatly enhanced by the method, which provided a new strategy to maintain the granular stability.
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Affiliation(s)
- Bei Long
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave.86, Ganzhou, 341000, Jiangxi, China
| | - Xinpeng Xuan
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave.86, Ganzhou, 341000, Jiangxi, China
| | - Changzhu Yang
- College of Environmental Science and Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan, 430074, Wuhan, China.
| | - Linan Zhang
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave.86, Ganzhou, 341000, Jiangxi, China
| | - Yuanyuan Cheng
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave.86, Ganzhou, 341000, Jiangxi, China
| | - Jianqi Wang
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Hongqi Ave.86, Ganzhou, 341000, Jiangxi, China
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26
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Bassin JP, Tavares DC, Borges RC, Dezotti M. Development of aerobic granular sludge under tropical climate conditions: The key role of inoculum adaptation under reduced sludge washout for stable granulation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 230:168-182. [PMID: 30292012 DOI: 10.1016/j.jenvman.2018.09.072] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/06/2018] [Accepted: 09/22/2018] [Indexed: 06/08/2023]
Abstract
Aerobic granular sludge (AGS) is a promising technology for wastewater treatment. However, the success of the process depends on the formation of stable granular biomass, which is associated with the microbiological aspects of the sludge and reactor operating conditions. In this study, the development of AGS from a poor nitrifying flocculent sludge obtained in a sewage treatment plant designed only for organic matter removal was assessed in a sequencing batch reactor (SBR) under tropical climate conditions (temperatures of 28 ± 4 °C). The results showed that, despite the alternating anaerobic-aerobic conditions during the granules selection phase under high sludge washout rates (low settling time), readily biodegradable organic matter was mainly removed aerobically. The formed granules were unstable, exhibiting a substantial amount of filaments and pasty consistency. The biomass characteristics (e.g., sludge volume index, density, diameter and settling velocity) were negatively impacted as complete granulation was reached, while biomass loss and degranulation became inevitable. Poor nitrification and no enhanced biological phosphate removal (EBPR) were observed. Implementation of a new operational strategy incorporating an adaptation of the seed sludge under reduced washout conditions (high settling time) prior to the granules selection stage enabled most of the influent organics to be removed anaerobically. Besides allowing a feast-famine regime to be established in the reactor, the sludge acclimation phase favoured the development of slow-growing organisms and suppressed the appearance of filamentous-like structures. Fast-settling granules with regular shape remained stable in the long-term, while high ammonium (>95%) and total nitrogen removal (>90%) was obtained. However, EBPR activity was very unstable, most likely due to the high temperatures. The findings of this study are important for the spreading of the AGS technology worldwide, especially in developing countries where the conditions are different in all aspects.
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Affiliation(s)
- J P Bassin
- Federal University of Rio de Janeiro - COPPE - Chemical Engineering Program, Rio de Janeiro, Brazil.
| | - D C Tavares
- Federal University of Rio de Janeiro - COPPE - Chemical Engineering Program, Rio de Janeiro, Brazil
| | - R C Borges
- Federal University of Rio de Janeiro - COPPE - Civil Engineering Program, Rio de Janeiro, Brazil
| | - M Dezotti
- Federal University of Rio de Janeiro - COPPE - Chemical Engineering Program, Rio de Janeiro, Brazil
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27
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Zhou JH, Zhou YC, Yu HC, Zhao YQ, Ye KQ, Fang JY, Wang HY. Determining the effects of aeration intensity and reactor height to diameter (H/D) ratio on granule stability based on bubble behavior analysis. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:784-796. [PMID: 30415362 DOI: 10.1007/s11356-018-3666-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
Aerobic granular sludge was considered as a leading wastewater technology in the next century. However, the loss of granule stability limited the application of this promising biotechnology. Increasing aeration intensity and height to diameter (H/D) ratio were conventional strategies to enhance granule stability. In this study, hydraulic effects of aeration intensity and H/D ratio were explored basing on bubble behavior analysis. However, results revealed that due to viscous resistance, increasing aeration intensity and H/D ratio had limited effects on enhancing hydraulic shear stress, not to mention the extra operation and construction cost. A deflector component was further applied to regulate hydraulic shear stress on large granules under low aeration intensity and H/D ratio. Hydraulic shear stress of large granules was constantly around 3.0 times higher than that in the conventional reactor, resulting in higher percentage of granules within optimal size range (81.95 ± 5.13%). A high abundance of denitrifying bacteria was observed in reactors, which led to high TN removal efficiency of 88.6 ± 3.8%.
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Affiliation(s)
- Jia Heng Zhou
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Yun Cheng Zhou
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Hao Cheng Yu
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Yi Qun Zhao
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Kai Qiang Ye
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Jing Yuan Fang
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Hong Yu Wang
- College of Civil Engineering and Architecture, Zhejiang University of Technology, No. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China.
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28
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Tomar SK, Chakraborty S. Effect of air flow rate on development of aerobic granules, biomass activity and nitrification efficiency for treating phenol, thiocyanate and ammonium. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 219:178-188. [PMID: 29738935 DOI: 10.1016/j.jenvman.2018.04.111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 03/30/2018] [Accepted: 04/25/2018] [Indexed: 06/08/2023]
Abstract
The impact of air flow rate on aerobic granulation was evaluated for treating toxic multiple pollutants; phenol (400 mg L-1), thiocyanate (100 mg L-1) and ammonia nitrogen (100 mg L-1) by using three lab scale sequencing batch reactors (SBRs) (R1, R2 and R3). Larger granules (2938.67 ± 64.91 μm) with higher biomass concentration (volatile solids of 4.17 ± 0.09 g L-1), higher granule settling velocity (55.56 ± 1.36 m h-1) and lower sludge volume index (35.25 ± 1.71 mL gTSS-1) were observed at optimal air flow rate of 2.5 L min-1 (R2). Confocal laser scanning microscopic images illustrated the extended fluorescence for extracellular polymeric substances in R2. In R2, partial nitrification was achieved. Phenol was completely removed in all the reactors while partial removal of SCN- and no nitrification were observed with a decrease (1.5 L min-1) and an increase (3.5 L min-1) in air flow rates (R1 and R3, respectively). This study provides an experimental contribution to examine the effect of optimal combination of aeration and toxic multiple pollutants, governing characteristics and nitrification efficiency of granules along with SBR performance in an economic way in terms of optimal air supply.
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Affiliation(s)
- Sachin Kumar Tomar
- Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Saswati Chakraborty
- Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, India.
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29
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Franca RD, Pinheiro HM, van Loosdrecht MC, Lourenço ND. Stability of aerobic granules during long-term bioreactor operation. Biotechnol Adv 2018; 36:228-246. [DOI: 10.1016/j.biotechadv.2017.11.005] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 09/30/2017] [Accepted: 11/14/2017] [Indexed: 10/18/2022]
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30
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Corsino SF, Capodici M, Torregrossa M, Viviani G. Fate of aerobic granular sludge in the long-term: The role of EPSs on the clogging of granular sludge porosity. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 183:541-550. [PMID: 27623364 DOI: 10.1016/j.jenvman.2016.09.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 08/30/2016] [Accepted: 09/01/2016] [Indexed: 06/06/2023]
Abstract
This work aims to investigate the stability of aerobic granular sludge in the long term, focusing on the clogging of the granular sludge porosity exerted by the extracellular polymeric substances (EPSs). The effects of different cycle lengths (short and long-term cycle) on the granular sludge stability were investigated. Results obtained outlined that during the short duration cycle, the formation and breakage of the aerobic granules were continuously observed. During this period, the excess of EPS production contributed to the clogging of the granules porosity, causing their breakage in the long run. During the long-duration cycle, the extended famine period entailed a greater EPSs consumption by bacteria, thus limiting the clogging of the porosity, and allowed obtaining stable aerobic granules. Reported results demonstrated that an excess in EPSs content could be detrimental to the stability of aerobic granular sludge in the long-term.
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Affiliation(s)
- Santo Fabio Corsino
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy.
| | - Marco Capodici
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
| | - Michele Torregrossa
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
| | - Gaspare Viviani
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
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31
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Deng S, Wang L, Su H. Role and influence of extracellular polymeric substances on the preparation of aerobic granular sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 173:49-54. [PMID: 26974237 DOI: 10.1016/j.jenvman.2016.03.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Revised: 03/04/2016] [Accepted: 03/05/2016] [Indexed: 06/05/2023]
Abstract
Due to the important role of the extracellular polymeric substances in the formation of aerobic granular sludge, the variation of the EPS contents in the process of cultivation and that in the one running cycle time were studied in this work. Aerobic granules with diameters between 0.8 and 1.1 mm were obtained within 30-35 days. The results suggested that the increase of EPS contents significantly contributed to the formation of aerobic granules. A linear relationship between the EPS and SVI was also developed, and it revealed that the aerobic granules had good settling property when the EPS exceeded 200 mg/g MLVSS. Two mainly components of EPS, protein (PN) and polysaccharides (PS), could act as the endogenous food for the microbes during the starvation period. The survival of the microbial population was jeopardized when the F/M ration was below 0.5 g COD/g SS d.
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Affiliation(s)
- Shuang Deng
- Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Luxi Wang
- Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Haijia Su
- Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, PR China.
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32
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Jiang Y, Wang H, Shang Y, Yang K. Simultaneous removal of aniline, nitrogen and phosphorus in aniline-containing wastewater treatment by using sequencing batch reactor. BIORESOURCE TECHNOLOGY 2016; 207:422-9. [PMID: 26906036 DOI: 10.1016/j.biortech.2016.02.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 02/01/2016] [Accepted: 02/04/2016] [Indexed: 05/24/2023]
Abstract
The high removal efficiencies of traditional biological aniline-degrading systems always lead to accumulation of ammonium. In this study, simultaneous removal of aniline, nitrogen and phosphorus in a single sequencing batch reactor was achieved by using anaerobic/aerobic/anoxic (A/O/A) operational process. The removal efficiencies of COD, NH4(+)-N, TN, TP were over 95.80%, 83.03%, 87.13%, 90.95%, respectively in most cases with 250mgL(-1) of initial aniline at 6h cycle when DO was 5.5±0.5mgL(-1). Aniline was able to be completely degraded when initial concentrations were less than 750mgL(-1). When DO increased, the removal rate of NH4(+)-N and TP slightly increased along with the moderate decrease of removal efficiencies of TN. The variation of HRT had obvious influence on removal performance of pollutants. The system showed high removal efficiencies of aniline, COD and nutrients during the variation of operating conditions, which might contribute to disposal of aniline-rich industrial wastewater.
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Affiliation(s)
- Yu Jiang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Yu Shang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Kai Yang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China.
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