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Nakaya Y, Jia J, Satoh H. Tracing morphological characteristics of activated sludge flocs by using a digital microscope and their effects on sludge dewatering and settling. ENVIRONMENTAL TECHNOLOGY 2024; 45:4042-4052. [PMID: 37475153 DOI: 10.1080/09593330.2023.2240026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 07/16/2023] [Indexed: 07/22/2023]
Abstract
ABSTRACTIn wastewater treatment by the activated sludge (AS) process, settleability and dewaterability of AS are key issues that are directly related to the treated water quality and sludge treatment costs. Several studies investigated the relationship between the shape of AS flocs and their settling/dewatering property. To quantify the floc morphology, it is imperative to attach a camera to a microscope or move the stage manually. Hence, labour and equipment costs may increase. In this study, by combining a digital microscope and an automatic stage, more than 100 magnified floc images were rapidly obtained from one AS sample dropped on a slide glass, and shape parameters were collectively calculated using an analysis software. During 1-year monitoring of four wastewater treatment plants in Sapporo City (Hokkaido, Japan), the morphological parameters and extracellular polymeric substances (EPS) quantity/quality of AS were analyzed on the basis of their correlation to the time to filtration (TTF) and sludge volume index (SVI), which are indicators for describing the dewatering and settling properties of AS, respectively. In one plant, larger, denser, and smoother flocs tended to contain less EPS and exhibited better sludge dewaterability. In another plant, larger, denser, and smoother flocs were considered to contribute to better settlement. Especially, an equivalent high-density floc diameter and the ratio of mixed liquor suspended solids (MLSS) concentration to the total floc area were commonly suggested to explain AS dewaterability and settleability.
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Affiliation(s)
- Yuki Nakaya
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Japan
| | - Jinming Jia
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Japan
| | - Hisashi Satoh
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Japan
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2
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Lv J, Zhao Q, Jiang J, Ding J, Wei L. Sludge dewaterability improvement with microbial fuel cell powered electro-Fenton system (MFCⓅEFs): Performance and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171422. [PMID: 38432365 DOI: 10.1016/j.scitotenv.2024.171422] [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: 01/03/2024] [Revised: 02/15/2024] [Accepted: 02/29/2024] [Indexed: 03/05/2024]
Abstract
Throughout the entire process of sludge treatment and disposal, it is crucial to explore stable and efficient techniques to improve sludge dewaterability, which can facilitate subsequent resource utilization and space and cost savings. Traditional Fenton oxidation has been widely researched to enhance the performance of sludge dewaterability, which was limited by the additional energy input and the instabilities of Fe2+ and H2O2. To reduce the consumption of energy and chemicals and further break the rate-limiting step of the iron cycle, a novel and feasible method that constructed microbial fuel cell powered electro-Fenton systems (MFCⓅEFs) with ferrite and biochar electrode (MgFe2O4@BC/CF) was successfully demonstrated. The MFCⓅEFs with MgFe2O4@BC/CF electrode achieved specific resistance filtration and sludge cake water content of 2.52 × 1012 m/kg and 66.54 %. Cellular structure and extracellular polymeric substances (EPS) were disrupted, releasing partially bound water and destroying hydrophilic structures to facilitate sludge flocs aggregation, which was attributed to the oxidation of hydroxyl radicals. The consistent electron supply supplied by MFCⓅEFs and catalytically active sites on the surface of the multifunctional functional group electrode was responsible for producing more hydroxyl radicals and possessing a better oxidizing ability. The study provided an innovative process for sludge dewaterability improvement with high efficiency and low energy consumption, which presented new insights into the green treatment of sludge.
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Affiliation(s)
- Jiaqi Lv
- State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qingliang Zhao
- State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Junqiu Jiang
- State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jing Ding
- State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Liangliang Wei
- State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
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Zhang W, Zhu L, Yang X, Zhu J, Dong B, Tao H. Targeted regulation of digestate dewaterability by the ozone/persulfate oxidation process. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 354:120332. [PMID: 38364539 DOI: 10.1016/j.jenvman.2024.120332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/14/2024] [Accepted: 02/08/2024] [Indexed: 02/18/2024]
Abstract
Dewatering is the first step in the subsequent treatment and disposal of food waste digestate (FWD). However, FWD is difficult to dewatering. In this study, persulfate was synergistic oxidized by ozone to improve digestate dewaterability. The optimal conditions was at pH = 3, O3=40 mg/g TS and PDS=0.1 g/g TS, under which the reductions in the normalized capillary suction time (NCST) and bound moisture (BM) of the FWD were 89.97% and 65.79%, respectively. Hydrophilic functional groups (oxygen- and nitrogen-containing groups) and hydrophilic protein molecular structures were decomposed by the reactive species of sulfate radical (SO4·-) and hydroxyl radicals (·OH) generated in the ozone-persulfate oxidation process, disrupting the binding between EPS and water molecules. The contributions of SO4·- and ·OH to digestate dewaterability were 42.51% and 28.55%. In addition, the introduction of H+ reduced electrostatic repulsion and contributed to the condensation of digestate flocs. The environmental implication assessment and economic analysis suggested that the O3/PDS oxidation process was cost-effective and has a low environmental implication when applied to the FWD dewaterability improvement process. These results can serve as a reference for the management of FWD and further improvement of FWD treatment and disposal efficiency.
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Affiliation(s)
- Wei Zhang
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China.
| | - Li Zhu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Xue Yang
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Jing Zhu
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Bin Dong
- School of Environmental Science and Engineering. Tongji University, Shanghai, 200092, PR China
| | - Hong Tao
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
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Tan X, Zeng S, Chen Z, Lv M, Tang X, He X, Chen Y, Wan Y, Zhang J. Synergistic effect of organic matter-floc size-bound water and multifactorial quantitative model of optimal reagent demand in sewage sludge conditioning process prior to dewatering. WATER RESEARCH 2024; 251:121108. [PMID: 38244300 DOI: 10.1016/j.watres.2024.121108] [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: 10/02/2023] [Revised: 12/20/2023] [Accepted: 01/04/2024] [Indexed: 01/22/2024]
Abstract
The high amount of densely hydrated organic substance present in sewage sludge impedes its filterability, thus restricting sludge disposal. Although chemical conditioning can facilitate filtration, the diverse sludge properties complicate the quantitative control of conditioning process. Investigating how to accurately quantify the optimal reagent demand (ORD) based on the critical physicochemical properties of the target sludge is an effective way to address the current issue. This study focused on the sewage and stockpiled sludge with varying properties, and their ORD under different chemical conditioning. The results showed that organic content, floc size, and bound water synergistically influenced conditioning process. The quantitative models were established between their coupling indicators and ORD, with coupling indicators including the ratio of organic content to floc size, the ratio of flow viscosity to floc size, and the ratio of the product of organic content and bound water to floc size. The linear correlation of the coupling indicator with ORD was higher than that of the traditional single-factor indicator. Furthermore, the inherent filterability of the sludge was somewhat separate from the adjustability of its filtration. A "dual-system" impact model was proposed to characterized the conditioning and filtration processes. These results provide theoretical guidance for the quantitative regulation of conditioning and filtration processes of sludge with complex characteristics.
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Affiliation(s)
- Xun Tan
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Sidong Zeng
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, PR China.
| | - Zhong Chen
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Mingquan Lv
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Xiaoya Tang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Xingxing He
- State Key Laboratory of Hydro-science and Engineering, Tsinghua University, Beijing 100084, PR China
| | - Yijun Chen
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Yong Wan
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Jingping Zhang
- Chongqing Yulanze Environmental Protection Technology Co, Chongqing, 408000, PR China
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Zhang D, Wang Y, Wang J, Fan X, Zhang S, Liu M, Ma L. Rethinking the relationships between gel like structure and sludge dewaterability based on a binary gel like structure model: Implications for the online sensing of dewaterability. WATER RESEARCH 2024; 249:120971. [PMID: 38101042 DOI: 10.1016/j.watres.2023.120971] [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: 05/12/2023] [Revised: 09/26/2023] [Accepted: 12/02/2023] [Indexed: 12/17/2023]
Abstract
The digital transformation of sludge treatment processes requires online sensing of dewaterability. This topic has been attempted for many years based on macroscopic shear rheology. However, the relationship between rheological behavior and dewaterability remains noncommittal, and the reason is unclear. Herein, a binary gel-like structure model was proposed including the interactions network at the supra-flocs level and the gel-like structure at the flocs level. Multiple advanced techniques including optical tweezers were employed to precisely understand the binary gel-like structure and to classify the correlation mechanism between this gel-like structure, rheological behavior, and dewaterability. The analysis of sludge from eight wastewater treatment plants showed the binary gel-like structures at both supra-flocs and flocs levels have significant relationships with sludge dewaterability (p < 0.05). Further deconstruction of the sludge viscoelastic behavior illustrated that the gel-like structure at the supra-flocs level dominates the rheological behavior of sludge. Moreover, the direct description of the binary gel-like structure in four typical sludge treatment processes highlighted the importance of the flocs level's structure in determining the dewaterability. Overall, this study revealed that shear rheology may prefer to stress the interactions network at the supra-flocs level but mask the flocs level's structure, although the latter is important. This observation may provide a general guideline for the design of robust sensors for dewaterability.
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Affiliation(s)
- Daxin Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; School of Soil & Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Yili Wang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
| | - Jingjing Wang
- Cell Biology Facility, Center of Biomedical Analysis, Tsinghua University, Beijing 100084, China
| | - Xiaoyang Fan
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Shuting Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Meilin Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Luyao Ma
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
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Bao P, Du C, Li Y, Jiang H, Zhou L, Yu G, Sun S, Zhou L, Li X, Teng J, Wang X, Wang J. Application of skeleton builders to sludge dewatering and disposal: A critical review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167106. [PMID: 37717769 DOI: 10.1016/j.scitotenv.2023.167106] [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: 08/11/2023] [Revised: 09/13/2023] [Accepted: 09/13/2023] [Indexed: 09/19/2023]
Abstract
With the development of cities and population, the production of sludge is increasing annually. It has become an unavoidable challenge to achieve sludge dewatering and disposal by a cost-effective, efficient and safe process. In this work, firstly, the factors limiting sludge dewatering are reviewed in terms of moisture distribution, sludge concentration, organic matter content, electronegativity, floc strength, and extracellular polymers (EPS). Subsequently, focusing on the dewatering technology about the skeleton builder, the recent progress of it is detailed in terms of mechanism, evaluation indicators, influencing factors, and technology coupling. In addition, the impact of skeleton builders on the sludge disposal stage is concluded. Finally, the challenges faced by sludge dewatering and skeleton builders are prospected. This review will provide some theoretical basis and technical guidance for subsequent experiments and practices regarding skeleton builders.
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Affiliation(s)
- Purui Bao
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Chunyan Du
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering Technology Research Center of Hunan Dongting Lake Flood Control and Water Resources Protection of Hunan Province, Hunan Water Resources and Hydropower Survey, Design, Planning and Research Co., Ltd, Changsha 410007, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China.
| | - Yifu Li
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China.
| | - Heng Jiang
- Engineering Technology Research Center of Hunan Dongting Lake Flood Control and Water Resources Protection of Hunan Province, Hunan Water Resources and Hydropower Survey, Design, Planning and Research Co., Ltd, Changsha 410007, China
| | - Lu Zhou
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Guanlong Yu
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Shiquan Sun
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Lean Zhou
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China; Engineering and Technical Center of Hunan Provincial Environmental Protection for River Lake Dredging Pollution Control, Changsha 410114, China
| | - Xue Li
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Junyi Teng
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Xiaowen Wang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Junchao Wang
- School of Hydraulic and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
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7
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Wu Z, Gao H, Chen Z, Su W, Jie Y, Zhu J, Yu R. Effect of predatory bacterial mixtures on biolysis of waste activated sludge to improve dewatering performance. ENVIRONMENTAL TECHNOLOGY 2023:1-32. [PMID: 38041588 DOI: 10.1080/09593330.2023.2291419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
The generation of surplus sludge during biological wastewater treatment has become a prevalent issue, necessitating the development of a dewatering approach that is efficient, economically feasible, and ecologically sound. Bdellovibrio-and-like organisms (BALOs) are obligatory parasitic bacteria that prey on an array of bacteria. In this study, different BALO strains were isolated and purified from waste activited sludge (WAS). Anti-predation host strains were applied to screen the BALO strains with different host-range to minimize the overlap of the biolysis prey spectrum. In addition, the BALO strains with different host preferences were mixed for sludge biolysis treatment efficiency comparison. The results indicated that the capillary suction time and the bound water content in the WAS treated with the mixed BALOs were significantly decreased by 25.9% ± 1.7% and 5.2% ± 1.2%, respectively, compared to those treated with the single BALO strain. The soluble chemical oxygen demand concentration in the mixed BALOs treated group was increased by 31.2% ± 0.7% than that treated with the single strain. The findings indicate that the mixed strains used in the treatment process resulted in a notable enhancement of both sludge dewatering performance and lysis degree. In addition, the abundance of Proteobacteria treated with the BALO mixtures decreased by 69.1% than the single strain treated one which demonstrated that the BALO mixture expanded the sludge host lysis spectrum. This study revealed the different effects of single and mixed strains on sludge community structure, suggesting that the BALO host range expansion is crucial to further improve sludge dewatering performances.
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Affiliation(s)
- Zeyu Wu
- Department of Environmental Science and Engineering, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, China 210096
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, China 210009
| | - Huan Gao
- Department of Environmental Science and Engineering, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, China 210096
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, China 210009
| | - Zhoukai Chen
- Department of Environmental Science and Engineering, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, China 210096
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, China 210009
- Hangzhou Planning and Design Academy, Hangzhou, Zhejiang, China, 310012
| | - Wenqiang Su
- Yang Zhong Bi Cheng Environmental Technology limited liability company, Yang Zhong, Jiangsu, China, 212200
| | - Yongfang Jie
- Yang Zhong Bi Cheng Environmental Technology limited liability company, Yang Zhong, Jiangsu, China, 212200
| | - Jian Zhu
- Yang Zhong Bi Cheng Environmental Technology limited liability company, Yang Zhong, Jiangsu, China, 212200
| | - Ran Yu
- Department of Environmental Science and Engineering, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, China 210096
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, China 210009
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Zhang YL, Sun P, Dai BB, Zheng SM, Ran DD, Wu TX, Zeng RJ, Wang HF. What affects the accuracy and applicability of determining wastewater sludge water content via low-field nuclear magnetic resonance? ENVIRONMENTAL RESEARCH 2023; 226:115702. [PMID: 36931372 DOI: 10.1016/j.envres.2023.115702] [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: 01/30/2023] [Revised: 03/10/2023] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
The accurate determination of waster sludge water content is crucial to sludge dewatering treatment and its disposal management. Though previous studies highlight the great advantages of low-field nuclear magnetic resonance (LF-NMR) in the determination of sludge water content, its accuracy and applicability are not well studied. Herein, this study investigated the settling of operating parameters and the properties of sludge samples on the accuracy and applicability of LF-NMR method in measuring sludge water content. The results showed that the setting of basic parameters such as standard curve, number of scanning times (NS) and sample weight affected the accuracy of sludge water content by LF-NMR. The standard calibration curve constructed by 3 g/L CuSO4, NS = 8 and the sample weight of about 5 g, were suitable for the accurate determination of sludge water content. Furthermore, the existence of magnetic substances in sludge can affect the distribution gradient of main magnetic field, and thus restricted the applicability of LF-NMR. The saturation magnetization of chemical reagents strongly correlated with the measured relative errors of sludge water content (r = 0.995, p < 0.01), the greater the saturation magnetization of the magnetic material, the greater the error of the test results. On the whole, it is necessary to fully consider the influence of process parameters and sludge properties to evaluate the accuracy and applicability of the LF-NMR method, rather than simply copying the parameters in literatures.
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Affiliation(s)
- Ya-Li Zhang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Ping Sun
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Bing-Bing Dai
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Shao-Ming Zheng
- Fujian Fiber Inspection Center, Fujian Provincial Key Laboratory of Textiles Inspection Technology, Fuzhou, 350002, China
| | - Dan-Di Ran
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Tian-Xin Wu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Raymond Jianxiong Zeng
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
| | - Hou-Feng Wang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
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Liang J, Zhou Y. Iron-based advanced oxidation processes for enhancing sludge dewaterability: State of the art, challenges, and sludge reuse. WATER RESEARCH 2022; 218:118499. [PMID: 35537253 DOI: 10.1016/j.watres.2022.118499] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
The increasing amount of sewage sludge produced in wastewater treatment plants (WWTPs) poses a great challenge to both environment and economy globally. As a requisite process during sludge treatment, sludge dewatering can significantly minimize the sludge volume and lower the operational cost for downstream transportation and disposal. Iron-based advanced oxidation process (AOP), a robust and cost-effective technique with relatively low technical barriers for high-level sludge dewatering, has been widely explored in the past 20 years. The development was mainly driven by the demands of efficient and sustainable sludge conditioning technology and the flexible sludge management approaches. The application of iron-based AOPs in sludge dewatering process attracts more and more attention. In this work, we discussed the current application of iron-based AOPs technology in the sludge dewatering processes in a holistic manner, summarized the factors affecting the sludge dewaterability in the treatment processes, and analyzed the mechanisms of iron-based AOPs to improve dewatering processes. Furthermore, we elaborated potential advantages, limitations, and challenges associated with implementing iron-based AOPs in the full-scale plants and shared the opportunities for sludge reutilization. This review aims to contribute to the development of highly efficient iron-based AOPs for sludge dewatering and offer perspectives and directions towards the new-generation of WWTPs with the sustainable and eco-friendly benefits.
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Affiliation(s)
- Jialin Liang
- Engineering and Technology Research Center for Agricultural Land Pollution Integrated Prevention and Control of Guangdong Higher Education Institute, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, China
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore.
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10
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Reinterpretation of the mechanism of coagulation and its effects in waste activated sludge treatment. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Dong Y, Yuan H, Bai L, Ge D, Zhu N. A comprehensive study on simultaneous enhancement of sludge dewaterability and elimination of polycyclic aromatic hydrocarbons by Fe 2+ catalyzing O 3 process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:152015. [PMID: 34843792 DOI: 10.1016/j.scitotenv.2021.152015] [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: 09/16/2021] [Revised: 11/12/2021] [Accepted: 11/23/2021] [Indexed: 06/13/2023]
Abstract
Simultaneous removal of polycyclic aromatic hydrocarbons (PAHs) in the process of enhancement of sludge dewaterability via oxidation of hydroxyl radicals (•OH) and flocculation of Fe3+ by Fe2+-catalyzing O3 were investigated as a novel research focus. The results showed that capillary suction time (CST) and water content of dewatered sludge cake (Wc) were reduced from 57.9 s and 85.1% to 13.6 s and 69.65% under the optimum usage of 60 mg/g dry solids (DS) O3 and 80 mg/g DS FeSO4, respectively. The relevant dewatering mechanism of Fe2+-catalyzing O3 treatment was elucidated. It was found that extracellular polymeric substances-bound (EPS-bound) and intracellular water was dramatically released through destroying sludge cells and EPS gel-like structure by produced •OH. In addition, the results of X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) and 13C NMR spectroscopy revealed that •OH oxidized and mineralized hydrophilic organic matters intensifying hydrophobicity of sludge surface. Moreover, Fe3+ generated by oxidation of Fe2+ agglomerated fragmented fine particles into large aggregates and decreased exposure of hydrophilic sites by neutralizing negative charge, which promoted water-solids separation. Meanwhile, sludge surface roughness was decreased which was determined by material type upright confocal laser microscope (CLM). As a consequence, •OH and Fe3+ were mainly responsible for enhancement of sludge dewaterability. Moreover, more than 40% of removal rate of PAHs was accomplished by Fe2+-catalyzed O3 treatment mitigating the environmental risks of PAHs spread.
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Affiliation(s)
- Yanting Dong
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haiping Yuan
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lu Bai
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Dongdong Ge
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Nanwen Zhu
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
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12
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Wang HF, Qi HY, Lian ZH, Zhang YL, Li J, Zeng RJ. A unified operating procedure is crucial to evaluate sludge dewaterability, taking the setup of refrigerated storage time as an example. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 307:114528. [PMID: 35091248 DOI: 10.1016/j.jenvman.2022.114528] [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: 09/17/2021] [Revised: 01/08/2022] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Although extensive efforts have been carried out to study sludge dewatering mechanism, the lack of universal operating procedures makes it never be satisfactorily explained. This study evaluated the impact of a unified operating procedure on waste activated sludge (WAS) dewaterability by taking the setup of refrigerated storage time as an example. It was found that storage time played an important role in determining WAS dewaterability and sampled WAS should be refrigerated within 2 days. The results showed that after 2-d storage, sludge filterability was deteriorated significantly while the extent of dewatering efficiency had little change. Meanwhile, increasing storage time greatly increased the release of extracellular polymeric substances (EPS) and heavy metals, decreased sludge viscosity and weakened its network strength, but had little impact on the floc size and zeta potential of the sludge samples. It can hardly reveal the mechanism of storage time on sludge dewaterability due to the non-uniformity of operating procedures in literatures, which is normally ignored. This study emphasizes a unified operating procedure is crucial to evaluate WAS dewaterability. Therefore, more efforts shall be focused on establishing the uniform operating procedure while advancing applied research in the field of sludge dewatering.
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Affiliation(s)
- Hou-Feng Wang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Hui-Yun Qi
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Ze-Han Lian
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Ya-Li Zhang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Jing Li
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
| | - Raymond Jianxiong Zeng
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
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13
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Li X, Shi Y, Zhou X, Wang L, Zhang H, Pi K, Gerson AR, Liu D. Adaptability of organic matter and solid content to Fe 2+/persulfate and skeleton builder conditioner for waste activated sludge dewatering. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:14819-14829. [PMID: 34617233 DOI: 10.1007/s11356-021-16404-x] [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: 03/19/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
Sludge conditioning is important for improved dewatering, with the sludge characteristics impacting the effect of conditioning. A composite conditioner, Fe2+-activated sodium persulfate (Fe2+/SPS) combined with phosphogypsum (PG), was used to examine its impact on sludges with different organic contents (34.6-43.8%) or different solid contents (2.8-5.9%). Response surface optimization analysis shows that when the best conditioning is achieved, the reduction of the specific resistance to filtration (SRF) is not sensitive to organic matter content, but the dewatering performance of the sludge is greatly affected by the solid content. The oxidation role of Fe2+/SPS and the skeleton builder role of PG together affect the conditioning, oxidation playing a major role in conditioning, especially for greater organic matter content. The organic content (maximum ηSOL value was 0.32) also affects the effectiveness of the skeleton builder more than the solid content (Maximum ηSOL value was 0.25). Changes in PG significantly impacts the optimal molar ratio and dosage of Fe2+/SPS. Sludge with greater solid content requires greater Fe2+/SPS dosage to provide stronger oxidation to destroy flocs, and the maximum Fe2+:SPS molar ratio was 1.14 with solid content of 5.9 wt%. The composite conditioning decreases the content of extracellular polymeric substances and proteins/polysaccharides. This study provides new insight into the relationship between the oxidation role of Fe2+/SPS and the skeleton builder role of PG for sludge conditioning strategies according to the optimal conditions.
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Affiliation(s)
- Xiaoran Li
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Yafei Shi
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China.
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, Wuhan, 430068, Hubei, China.
| | - Xi Zhou
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Lu Wang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Huiqin Zhang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
| | - Kewu Pi
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, Wuhan, 430068, Hubei, China
| | - Andrea R Gerson
- Blue Minerals Consultancy, Wattle Grove, Tasmania, 7109, Australia
| | - Defu Liu
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, 430068, Hubei, China
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, Wuhan, 430068, Hubei, China
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14
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Liang J, Luo L, Li D, Varjani S, Xu Y, Wong JWC. Promoting anaerobic co-digestion of sewage sludge and food waste with different types of conductive materials: Performance, stability, and underlying mechanism. BIORESOURCE TECHNOLOGY 2021; 337:125384. [PMID: 34186331 DOI: 10.1016/j.biortech.2021.125384] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 06/13/2023]
Abstract
In this research, we investigated and compared the effects of three widely used conductive materials, e.g., zero-valent iron (Fe0), magnetite (Fe3O4), and biochar on the performance, stability, and in-depth mechanism during the anaerobic co-digestion process of sewage sludge and food waste. Among the three conductive materials, Fe0 could achieve the highest cumulative methane production of 394.0 mL/g volatile solids (VS) added, which was 1.24-fold and 1.17-fold higher than that receiving Fe3O4 and biochar. The mechanistic studies indicated that compared to the Fe3O4 and biochar groups, Fe0 could significantly enhance the release of soluble protein, polysaccharide, and dissolved organic matters, the degradation of volatile fatty acids and VS, and the activities of key enzymes and direct interspecies electron transfer (DIET). Consequently, the methane yield and digestate dewaterability were notably improved. Collectively, these findings will offer suggestions of the preferable conductive materials in the anaerobic co-digestion process for decision makers.
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Affiliation(s)
- Jialin Liang
- Institute of Bioresource and Agriculture, Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Liwen Luo
- Institute of Bioresource and Agriculture, Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Dongyi Li
- Institute of Bioresource and Agriculture, Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, Gujarat 382 010, India
| | - Yunjie Xu
- School of Technology, Huzhou University, Huzhou 311800, China
| | - Jonathan W C Wong
- Institute of Bioresource and Agriculture, Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China; School of Technology, Huzhou University, Huzhou 311800, China.
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15
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Guo S, Zhou L, Huang Y, Huang X. Insight into the comparison of thermally and Fe(II) activated persulfate on sludge dewaterability and disintegration. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 84:1464-1476. [PMID: 34559080 DOI: 10.2166/wst.2021.337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The effects of thermally and Fe(II) activated potassium persulfate (PPS) on sludge dewatering performance were compared systematically. Sludge dewaterability was monitored by measuring capillary suction time (CST) and sludge specific resistance to filtration (SRF), and the degradation effect was characterized by chemical oxygen demand (COD), total organic carbon (TOC), ammonia nitrogen (NH4+-N) and extracellular polymeric substances (EPS). The change of extracellular polymer substance (EPS) including soluble, loosely bound and tightly bound EPS (S-EPS, LB-EPS and TB-EPS) with time and PPS dosage was monitored to discuss the oxidation efficiency of thermally and Fe(II) activated PPS. Sludge supernatant was analyzed by three-dimensional fluorescence excitation-emission spectra (3D-EEM) to confirm the protein transformation. The result showed that sludge dewaterability in terms of CST and SRF were enhanced with increasing PPS dosage and condition time of two activated methods. While Fe(II) activated PPS could reduce sludge CST and SRF to preferred values at low PPS dosage and short condition time. Meanwhile, sludge degradation effect was also more obvious. Mechanically, sludge TB-EPS in proteins and polysaccharides converted to SB-EPS was faster with Fe(II) activated PPS. In addition, thermally activated PPS tended to oxidize the protein in the supernatant first.
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Affiliation(s)
- Shaodong Guo
- School of Urban Construction, Wuhan University of Science and Technology, 2 of Huangjiahu West Road, Hongshan District, Wuhan 430065, Hubei, China E-mail:
| | - Long Zhou
- School of Urban Construction, Wuhan University of Science and Technology, 2 of Huangjiahu West Road, Hongshan District, Wuhan 430065, Hubei, China E-mail:
| | - Yuxin Huang
- School of Urban Construction, Wuhan University of Science and Technology, 2 of Huangjiahu West Road, Hongshan District, Wuhan 430065, Hubei, China E-mail:
| | - Xinghu Huang
- School of Urban Construction, Wuhan University of Science and Technology, 2 of Huangjiahu West Road, Hongshan District, Wuhan 430065, Hubei, China E-mail:
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16
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Dong Y, Gu M, Yuan H, Zhu N. Insights into the enhancement of waste activated sludge dewaterability using sodium dichloroisocyanurate and dodecyl dimethyl ammonium chloride: Performance, mechanism, and implication. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146302. [PMID: 34030389 DOI: 10.1016/j.scitotenv.2021.146302] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 06/12/2023]
Abstract
Sludge dewatering is essential for reduction of sludge volume to cut the cost of transportation and disposal. Combined application of sodium dichloroisocyanurate (DCCNa) and dodecyl dimethyl ammonium chloride (DDAC) was attempted to promote sludge dewatering performance and physicochemical properties for the first time in this work. The results showed that capillary suction time (CST) and moisture content of dewatered sludge cake (Mc) decreased to 15.9 s and 61.54% compared to 144.5 s and 90.39% of raw sludge, respectively, with the addition of optimal dosage of 150 mg DCCNa/g DS and 125 mg DDAC/g DS. The conditioning mechanism of combined treatment was elucidated by investigating the variations of extracellular polymeric substances (EPS) composition, flocs morphological structure, rheological behavior, moisture distribution and Fourier transform infrared (FTIR) of sludge. It could be found that sludge floc cells were decomposed and bound water was released after DCCNa treatment. The bound water content was further decreased with the presence of DDAC. In addition, DDAC not only increased the zeta potential and flowability of sludge, but also reduced the surface tension and interact with oxygen-containing functional groups in sludge. As a result, the sludge dewaterability was significantly improved. Moreover, the calorific value analysis of dewatered sludge cake indicated that combined conditioning of DCCNa and DDAC presented the advantage of incineration disposal.
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Affiliation(s)
- Yanting Dong
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Minxue Gu
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Haiping Yuan
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Nanwen Zhu
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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17
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Sha L, Yu X, Wu Z, Liu X, Wang H, Jiang Q, Zhang S. Study of the variations in apparent electrical resistivity of activated sludge during the electro-dewatering process. ENVIRONMENTAL RESEARCH 2021; 198:110453. [PMID: 33188765 DOI: 10.1016/j.envres.2020.110453] [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: 08/14/2020] [Revised: 10/15/2020] [Accepted: 11/08/2020] [Indexed: 06/11/2023]
Abstract
The high energy consumption of high apparent electrical resistivity (AER) in sludge during the later stages of the electro-dewatering (EDW) process is a difficult problem; however, analysis of sludge AER may contribute to a reduction in energy consumption. In this study, the variations in the AER of activated sludge and potential mechanisms related to sludge properties were systematically examined. First, a sludge cake was divided into four horizontal layers, in order to investigate the sludge AER in each layer. Then, the effects of variations in water distribution, oxidation-reduction potential (ORP), pH, metal ions, sludge conductivity, zeta potential, temperature, and sludge microstructure on the AER in each layer were explored. The results showed that the sludge AER began to increase from the bottom layers to the top layers when the moisture content (MC) was decreased to 60%. The formation of nonionic chemical systems and the gas barrier layer could increase the AER in the top layers, and the increase in sludge AER in the bottom layers was due to the decrease in MC and sludge conductivity. In addition, electrolyte release and electromigration had a significant effect on the sludge AER. This work identifies potential causes for the increase in AER, and provides a reference for solving problems related to high AER in sludge during the later stages of the EDW process.
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Affiliation(s)
- Li Sha
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300354, China
| | - Xiaoyan Yu
- School of Environmental and Safety Engineering, Taiyuan Institute of Technology, Taiyuan, 030008, China
| | - Zhangxiang Wu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300354, China
| | - Xingxin Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300354, China
| | - Haozhe Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300354, China
| | - Qingqing Jiang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300354, China
| | - Shuting Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300354, China.
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