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Yang N, Yang S. Neglected sludge solid phase in sludge pretreatment process: Physicochemical characterization and mechanism study of its role in anaerobic degradation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 944:173769. [PMID: 38848921 DOI: 10.1016/j.scitotenv.2024.173769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 06/01/2024] [Accepted: 06/02/2024] [Indexed: 06/09/2024]
Abstract
The low anaerobic digestion efficiency of the solid phase separated from pre-treated sludge indicates the need to explore other suitable resource utilization pathways for sludge solid phase. However, there is a lack of comprehensive and in-depth research on the physicochemical properties of sludge solid phase. This study comprehensively analyzes the characteristics of sludge solid phase and elucidates the mechanism of sludge solid phase in the anaerobic degradation of toxic wastewater. The results show that the surface free energy of sludge solid phase after different pre-treatments is mainly contributed by Lewis acid-base hydration free energy. The distribution of proteins on the surface of sludge solid phase plays a major role in the adhesion between sludge solid particles. Metal ions in the sludge solid phase are mainly present in the exchange state, followed by the carbonate state and the organics-bound state. The sludge solid phase obtained by sludge pH 12 + 150 °C treatment has the highest conductivity (1.36 mS/m) and capacitance (25.51 μF/g), mainly due to the presence of melanoidins in the sludge solid phase, which has similar semiquinone radicals to humic acids, thus increasing conductivity. The addition of sludge solid phase promotes an increase in cumulative methane production and rate of methane production. The sludge solid phase might play a role of an auxiliary carbon source acting as an adsorbent to buffer against toxicity inhibition and facilitate electron transfer. This study reveals the characteristics of sludge solid phase and its role in anaerobic digestion, providing theoretical guidance for finding suitable resource utilization pathways for sludge solid phase.
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Affiliation(s)
- Ning Yang
- Department of Environmental Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Shucheng Yang
- Department of Environmental Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
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2
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Wen L, Lin L, Fan YA, Luo Y, Ma SS, Zhou Y, Yang C, Shih K, Li XY. Valorization of thermally hydrolyzed sludge with clay for sintering of ceramic tiles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 877:162871. [PMID: 36933740 DOI: 10.1016/j.scitotenv.2023.162871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 05/06/2023]
Abstract
The disposal of wastewater sludge is one of the most challenging environmental problems for large cities. Wastewater sludge may be utilized as a feasible substitute for clay to sinter ceramics, given their similar mineralogical composition. However, the organics in sludge will be wasted, while their release during sintering will leave cracks in the ceramic products. In this research, after the thermal treatment for effective organic recovery, the thermally hydrolyzed sludge (THS) is incorporated with clay for the sintering of construction ceramics. The experimental results showed that a THS dosing ratio up to 40 % can be achieved for mixing with montmorillonite clay to make ceramic tiles. The sintered tiles (THS-40) had an intact shape and structure, and the tile performance was close to that made from single montmorillonite (THS-0), with water absorption of 0.4 % vs. 0.2 %, compressive strength of 136.8 vs. 140.7 MPa, and undetected heavy metal leaching. Further addition of THS would lead to a considerable deterioration of the quality of the tiles to a compressive strength of as low as 5.0 MPa for the THS only product (THS-100). Comparing with the tiles incorporated with raw sludge (RS-40), the THS-40 tiles had a more intact and denser structure with a 10 % improved compressive strength. Cristobalite, aluminum phosphate, mullite, and hematite dominated in the THS-born ceramics, which are typical components of ceramics, and the amount of hematite increased with the THS dosing ratio. Sintering at a high temperature of 1200 °C enabled efficient phase transformation from quartz to cristobalite and from muscovite to mullite, which ensured the toughness and compactness of the THS-born ceramic tiles.
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Affiliation(s)
- Lei Wen
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong
| | - Lin Lin
- Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
| | - Yi-Ang Fan
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong
| | - Yang Luo
- Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland
| | - Sheng-Shou Ma
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong
| | - Ying Zhou
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong
| | - Chao Yang
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong
| | - Kaimin Shih
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong
| | - Xiao-Yan Li
- Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong; Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
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3
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Liu Y, Yuan H, Zhu N, Yuan Z. Effect of thermal hydrolysis pretreatment on the stabilization of sludge with different solid contents during autothermal thermophilic aerobic digestion. ENVIRONMENTAL RESEARCH 2023:116347. [PMID: 37290618 DOI: 10.1016/j.envres.2023.116347] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/04/2023] [Accepted: 06/06/2023] [Indexed: 06/10/2023]
Abstract
Sludge stabilization was affected by solid content during autothermal thermophilic aerobic digestion (ATAD). Thermal hydrolysis pretreatment (THP) could alleviate the issues of high viscosity, slow solubilization and low ATAD efficiency caused by increased solid content. The influence of THP on the stabilization of sludge with different solid contents (5.24%-17.14%) during ATAD was investigated in this study. The results demonstrated that stabilization was achieved with volatile solid (VS) removal of 39.0%-40.4% after 7-9 days of ATAD for sludge with solid content of 5.24%-17.14%. The solubilization of sludge with different solid contents reached 40.1%-45.0% after THP. The rheological analysis indicated that the apparent viscosity of sludge was obviously reduced after THP at different solid contents. The increase in fluorescence intensity of fulvic acid-like organics, soluble microbial by-products and humic acid-like organics in the supernatant after THP and the decrease in fluorescence intensity of soluble microbial by-products after ATAD were detected by excitation emission matrix (EEM). The molecular weight (MW) distribution in the supernatant elucidated that the proportion of 50 kDa < MW < 100 kDa increased to 16%-34% after THP and the proportion of 10 kDa < MW < 50 kDa decreased to 8%-24% after ATAD. High throughput sequencing showed that the dominant bacterial genera shifted from Acinetobacter, Defluviicoccus and Norank_f__norank_o__PeM15 to Sphaerobacter and Bacillus during ATAD. This work revealed that solid content of 13%-17% was appropriate for efficient ATAD and rapid stabilization under THP.
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Affiliation(s)
- Yangyang Liu
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haiping Yuan
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Nanwen Zhu
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Zhihang Yuan
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
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4
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Yan W, Song M, Zhou Y. Redistribution of perfluorooctanoic acid in sludge after thermal hydrolysis: Location of protein plays a major role. WATER RESEARCH 2023; 241:120135. [PMID: 37267707 DOI: 10.1016/j.watres.2023.120135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/04/2023]
Abstract
Perfluorinated compounds (PFCs) are a group of bio-recalcitrant pollutants that remain in waste activated sludge and may subsequently be transferred with sludge to thermal hydrolysis pretreatment (THP) process. Instead of reduction, it is observed previously that the concentration of free PFCs elevated after THP. By employing perfluorooctanoic acid (PFOA) as a representative, this study developed a hierarchical scheme to pinpoint the key factors that contribute to free PFOA elevation from the complex sludge transformations. According to the results, the relative abundance of PFOA in the liquid phase increased by 11.7 - 22.9% during THP. In the solid phase, the amide groups reduction and the spatial structure change of proteins weakened the sorption capability of solids for PFOA. In the liquid phase, the increase of proteins, which could bind and form static hindrance to regulate the behavior of PFOA, was the main factor to retain PFOA in liquid. In contrast, other sludge transformations including changes in pH, zeta potential, ionic condition and specific surface area, displayed insignificant impact on the redistribution process. The study presents a detailed picture on how sludge transformations would regulate PFCs distribution that ultimately direct the selection of further treatment processes.
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Affiliation(s)
- Wangwang Yan
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong 518107, China; Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Cleantech One #06-08, 637141, Singapore
| | - Mengsha Song
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Gongchang Road, Guangming District, Guangdong 518107, China
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Cleantech One #06-08, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore.
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5
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Cai S, Zhang Y, Hu A, Liu M, Wu H, Wang D, Zhang W. Dissolved organic matter transformation mechanisms and process optimization of wastewater sludge hydrothermal humification treatment for producing plant biostimulants. WATER RESEARCH 2023; 235:119910. [PMID: 37001233 DOI: 10.1016/j.watres.2023.119910] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/08/2023] [Accepted: 03/22/2023] [Indexed: 06/19/2023]
Abstract
Understanding the composition, transformation and bioactivity of dissolved organic matter (DOM) at the molecular level is crucial for investigating the hydrothermal humification process of wastewater sludge and producing ecological fertilizers. In this study, DOM transformation pathways under alkali-thermal humification treatment (AHT) were characterized by Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) in conjunction with molecular reaction network analysis. The effects of DOM on plant growth were examined using hydroponics and transcriptomic analysis. In the wastewater sludge humification process, AHT produced maximum amounts of protein (3260.56 mg/L) and humic acid (5788.24 mg/L) after 12 h. FT-ICR MS results indicated that protein-like structures were prone to continuous oxidation and were ultimately transformed into aromatic N-containing compounds resembling humic substances. Several reactive fragments (such as -C2H2O2, -C3H4O2, and -C4H6O2) formed by the Maillard reaction (MR) were identified as potential precursors to humic acid (HA). In terms of biological effects, DOM12h showed the highest rice germination and growth activity, whereas that produced by AHT for a longer period (> 12 h) displayed phytotoxicity owing to the accumulation of toxic substances. Plant biostimulants (such as amino acids and HAs) in DOM improved energy metabolism and carbohydrate storage in rice seedlings by upregulating the "starch and sucrose metabolism" pathways. Toxic substances (such as pyrrole, pyridine, and melanoidin) in DOM can activate cell walls formation to inhibit abiotic stimuli in rice seedlings through the biosynthesis of phenylpropanoid pathway. These findings provide a theoretical basis for optimizing sludge hydrothermal humification and recovering high-quality liquid fertilizers.
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Affiliation(s)
- Siying Cai
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Yu Zhang
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Aibin Hu
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Ming Liu
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Hanjun Wu
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430074, Hubei, China
| | - Dongsheng Wang
- Department of environmental engineering, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Weijun Zhang
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China; National Engineering Laboratory of High Concentration Refractory Organic Wastewater Treatment Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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6
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Wang L, Liu T, Xu J, Wang Z, Lei Z, Shimizu K, Zhang Z, Yuan T. Enhanced economic benefit of recycling Fe 3O 4 for promotion of volatile fatty acids production in anaerobic fermentation of food waste. BIORESOURCE TECHNOLOGY 2023; 369:128428. [PMID: 36470492 DOI: 10.1016/j.biortech.2022.128428] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 11/28/2022] [Accepted: 11/29/2022] [Indexed: 06/17/2023]
Abstract
Fe3O4 addition in anaerobic fermentation of food waste (FW) is promising for enhancing volatile fatty acids (VFAs) production. However, the large amount of Fe3O4 in the digestate fertilizer leads to the waste of resources and possible toxicity to organisms. Thus, this study investigated the feasibility of Fe3O4 recycling for VFAs enhancement in anaerobic fermentation of FW and performed the cost-benefit evaluation of this process. Results revealed that Fe3O4 could be successfully recycled twice with recovery rates of 71.5% and 65.5%, respectively. X-ray diffraction analysis revealed a slight change to the Fe2O3-like structure after 2-time recycling. The VFAs yields were enhanced by 17.2% and 17.0% in Cycles 1 and 2 owing to the enhanced activities of hydrolytic and acid-forming enzymes. The net income of the Fe3O4 recycling process was about 13-fold higher than that of the conventional treatment process, suggesting a promising and economically feasible strategy for enhancing VFAs production.
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Affiliation(s)
- Lanting Wang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tianxiao Liu
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Jing Xu
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhiwei Wang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Faculty of Life Sciences, Toyo University, 1-1-1 Izumino, Oura-gun Itakura, Gunma 374-0193, Japan
| | - Zhenya Zhang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
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7
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Zhuo Y, Yang P, Zhou M, Zhu J, Wen T, Peng D, Han Y. Performance and methane potential of up-flow anaerobic sludge blanket treating thermal hydrolyzed sludge dewatering liquor. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 154:209-216. [PMID: 36257180 DOI: 10.1016/j.wasman.2022.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 10/02/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
Thermal hydrolysis pretreatment could release organic sufficiently from solid into liquid phase to accelerate the high solid sludge anaerobic digestion. Thus, up-flow anaerobic sludge blanket (UASB) could be a promising energy recovery process to treat thermal hydrolyzed sludge dewatering liquor with significantly augmented the organic loading rate (OLR). In this study, its performance was investigated using a lab-scale UASB to treat sludge dewatering liquor after 165 °C, 30 min thermal hydrolysis pretreatment. The results show that 85.57% of the organic in thermal hydrolyzed sludge dewatering liquor could be converted to methane. The UASB adapts to high OLR stably, and the COD removal efficiency was 71.98 ± 1.95% at OLR of 18.35 ± 0.78 kgCOD·(m3·d)-1, and the gap between the maximum potential and experimental methane production yields could be observed during different OLRs. It could be explained as the methanogenesis rate decreased due to the shift of dominant pathway from acetoclastic methanogenesis to syntrophic acetate oxidation following hydrogenotrophic methanogenesis. Methanospirillum became the dominant methanogen with the increase of OLR. In addition, the methane production yield and rate would be hindered till the ammonia nitrogen concentration exceeds 4 g·L-1. Direct interspecies electron transfer could be promising methods to improve UASB performance treating thermal hydrolyzed dewatering liquor.
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Affiliation(s)
- Yang Zhuo
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Peizhen Yang
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Mengyu Zhou
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junzhao Zhu
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tianxiang Wen
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Dangcong Peng
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yun Han
- School of Municipal and Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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8
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Xu Q, Luo L, Li D, Johnravindar D, Varjani S, Wong JWC, Zhao J. Hydrochar prepared from digestate improves anaerobic co-digestion of food waste and sewage sludge: Performance, mechanisms, and implication. BIORESOURCE TECHNOLOGY 2022; 362:127765. [PMID: 35985463 DOI: 10.1016/j.biortech.2022.127765] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 06/15/2023]
Abstract
This work reported a new waste functionalization and utilization method, which use digestate to prepare hydrochar to improve methane production from food waste (FW) and sewage sludge (SS). Experimental results presented that 10 g/L hydrochar obtained the cumulative methane production of 133.11 ± 1.18 mL/g volatile solids added, 26.99 % higher than that without hydrochar addition. By monitoring the conversion of model metabolic intermediates, 10 g/L hydrochar was determined to favor hydrolysis, acidogenesis and methonogenesis bio-processes involved in methane production, thus improving the degradation of solubilized organics and consumption of short-chain fatty acids (SCFAs) during the co-digestion. Microbial investigation revealed that 10 g/L hydrochar enriched the microbes relevant to methane production (e.g., Methanosaeta and Syntrophomonas), but reduced the abundances of hydrolysis- and acidogenesis-related microbes (e.g., Acinetobacter). This hydrochar-based preparation and utilization strategy might offer a novel paradigm for waste-control-waste, bringing economic and environmental benefits.
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Affiliation(s)
- Qiuxiang Xu
- Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region
| | - Liwen Luo
- Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region
| | - Dongyi Li
- Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region
| | - Davidraj Johnravindar
- Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, Gujarat 382010, India
| | - Jonathan W C Wong
- Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region
| | - Jun Zhao
- Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region.
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9
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Yu H, Gu L, Zhang D, Wen H, Wang M, Zhu N. Enhancement of sludge dewaterability by three-dimensional electrolysis with sludge-based particle electrodes. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120599] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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10
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Construction of Recombinant Magnetospirillum Strains for Nitrate Removal from Wastewater Based on Magnetic Adsorption. Processes (Basel) 2022. [DOI: 10.3390/pr10030591] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Nitrate ion (NO3−) in wastewater is a major cause of pollution in aquatic environments worldwide. Magnetospirillum gryphiswaldense (MSR-1) has a complete dissimilatory denitrification pathway, converts NO3− in water into nitrogen (N2) and simultaneously removes ammonium ions (NH4+). We investigated and confirmed direct effects of regulatory protein factors Mg2046 and MgFnr on MSR-1 denitrification pathway by EMSAs and ChIP-qPCR assays. Corresponding mutant strains were constructed. Denitrification efficiency in synthetic wastewater medium during a 12-h cell growth period was significantly higher for mutant strain Δmgfnr (0.456 mmol·L−1·h−1) than for wild-type (0.362 mmol·L−1·h−1). Presence of magnetic particles (magnetosomes) in MSR-1 greatly facilitates collection and isolation of bacterial cells (and activated sludge) by addition of a magnetic field. The easy separation of magnetotactic bacteria, such as MSR-1 and Δmgfnr, from wastewater using magnetic fields is a unique feature that makes them promising candidates for practical application in wastewater treatment and sludge pretreatment.
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11
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Liu X, Meng Q, Wu F, Zhang C, Tan X, Wan C. Enhanced biogas production in anaerobic digestion of sludge medicated by biochar prepared from excess sludge: Role of persistent free radicals and electron mediators. BIORESOURCE TECHNOLOGY 2022; 347:126422. [PMID: 34838963 DOI: 10.1016/j.biortech.2021.126422] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/17/2021] [Accepted: 11/21/2021] [Indexed: 06/13/2023]
Abstract
The addition of biochars to promote the efficiency of anaerobic digestion (AD) has widely received concerns. However, the role of persistent free radicals (PFRs) and the electron transfer ability of biochar in AD has not yet been noticed. In this study, biochars were prepared from excess sludge under 400 °C (B400) or 600 °C (B600) and different ratios of sludge to biochar (5:1, 10:1, 20:1) were applied in the AD of sludge. The results verified that PFRs in biochar participated in the sterilization of microorganisms in sludge, resulting in the release of organic matters. Similar to electron mediators, biochars possessed electron exchangeability and the addition of biochars boosted the biogas production by maximum of 54.5%. The enhancing effect of B400 surpassed that of B600 as high temperature destroyed functional groups and reduced the defect degree of biochar. This study achieved in-situ resource utilization and provided references for the improvement of anaerobic digestion.
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Affiliation(s)
- Xiang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Qingting Meng
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Fengjie Wu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Chen Zhang
- Shanghai Municipal Engineering Design Institute Group Co Ltd, Shanghai 200092, China
| | - Xuejun Tan
- Shanghai Municipal Engineering Design Institute Group Co Ltd, Shanghai 200092, China
| | - Chunli Wan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China.
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12
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Qiu C, Xu W, Wang Y, Yang J, Su X, Lin Z. Hydrothermal alkaline conversion of sewage sludge: optimization of process parameters and characterization of humic acid. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:57695-57705. [PMID: 34091839 DOI: 10.1007/s11356-021-14711-x] [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: 02/10/2021] [Accepted: 05/31/2021] [Indexed: 06/12/2023]
Abstract
Sewage sludge (SS) dewatering is a key step in sludge disposal, which plays an important role in reducing sludge volume, facilitating transportation and subsequent treatment. In this paper, a facile hydrothermal-alkaline treatment for SS was proposed, which can be used for sludge dewatering and humic acid (HA) recycling at the same time. Response surface methodology (RSM) was used to determine the optimal conditions, and a mathematical model was established to accurately predict the changes of sludge water content and the extraction rate of HA. Under the optimal conditions of 170 °C/42 min/0.05 (for hydrothermal temperature, hydrothermal time, and mass ratio of KOH to wet sludge, respectively), the water content decreased to 46.7% and the extraction rate of HA (with a purity of 96.2%) was 89.1%. The improvement of the dewatering performance effectively facilitates the subsequent disposal of the sludge. The hydrothermal-alkaline method not only realizes the efficient dehydration of the sludge, but also obtains HA from the sludge extract. The obtained HA has potential economic value in the fields of agriculture, biological medicine, environment, and the like.
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Affiliation(s)
- Chen Qiu
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, People's Republic of China
- China-Singapore International Joint Research Institute, Guangzhou, 510000, People's Republic of China
| | - Wenbing Xu
- Dongjiang Environmental Company Limited, Shenzhen, Guangdong, 518057, People's Republic of China
| | - Yanjie Wang
- Dongjiang Environmental Company Limited, Shenzhen, Guangdong, 518057, People's Republic of China
| | - Jiakuan Yang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Xintai Su
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, People's Republic of China.
- China-Singapore International Joint Research Institute, Guangzhou, 510000, People's Republic of China.
| | - Zhang Lin
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, People's Republic of China
- China-Singapore International Joint Research Institute, Guangzhou, 510000, People's Republic of China
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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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14
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Jiang Q, Zhang C, Wu P, Ding P, Zhang Y, Cui MH, Liu H. Algae biochar enhanced methanogenesis by enriching specific methanogens at low inoculation ratio during sludge anaerobic digestion. BIORESOURCE TECHNOLOGY 2021; 338:125493. [PMID: 34273625 DOI: 10.1016/j.biortech.2021.125493] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 06/26/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
Carbon materials are promising in improving the performance of anaerobic digestion, however, interactive mechanisms between the carbon-based enhancement and operating parameters remained unclear. Using anaerobic digested sludge as inoculum, the effects of Taihu blue algae biochar (ABC) on methanogenesis at different inoculation ratios were investigated during sludge anaerobic digestion. Results showed that ABC enhanced methane productions at the lower inoculation ratios (4% and 1%, v/v), but not at the higher ratio (10%, v/v). Mechanism analysis demonstrated methanogenic improvements at the lower inoculation ratios were not owing to initial organic loading rate increments. Otherwise, ABC addition at the lower inoculation ratios were more favorable for the enrichment of Methanosarcina than the higher ratio, which might be benefit for methanogenesis through directed interspecies electron transfer. Thus, for the improvement of sludge anaerobic digestion, the microbial enrichments at different inoculation ratios would be more important than the merely biochar addition.
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Affiliation(s)
- Qian Jiang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Chao Zhang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Ping Wu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Peng Ding
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Yan Zhang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou 215011, China
| | - Min-Hua Cui
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou 215011, China
| | - He Liu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou 215011, China.
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Gao S, Lu D, Qian T, Zhou Y. Thermal hydrolyzed food waste liquor as liquid organic fertilizer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 775:145786. [PMID: 33621877 DOI: 10.1016/j.scitotenv.2021.145786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 02/05/2021] [Accepted: 02/06/2021] [Indexed: 06/12/2023]
Abstract
Thermal hydrolysis (TH) is an efficient technology for food waste (FW) management. This study investigated the nutrients released from FW under various TH temperature (140, 160, 180, 200 and 220 °C) and evaluated the feasibility of the hydrolyzed liquor (HL) as liquid organic fertilizer. The phytotoxicity and biotoxicity of HL was analyzed using wheat seed and Pseudomonas putida. Results revealed that TH could effectively solubilize FW and release nutrients (N, P and K) and organic substances. The highest content of total nitrogen (TN, 1685 mgN/L) and phosphorus (TP, 235 mgP/L) in the HL was obtained under 180 °C. The K+ was 278-293 mg/L regardless of treatment temperature. Secondary nutrients (Ca and Mg) and micro metals (Fe, Cu, Zn, Al, Co and Mn) were all detected at relatively high level, while heavy metals (As and Cd) were generally lower than 0.5 mg/L. Twenty types of free amino acid were identified and the maximum total concentration was 4965.13 mg/L. 2% HL displayed higher germination index (>80%) and enhanced root and shoot lengths. No biotoxicity was observed as confirmed by the bioassay. This study proposes a feasible method to solubilize food waste and produce liquid organic fertilizer.
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Affiliation(s)
- Shumei Gao
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing 314001, Zhejiang, China
| | - Dan Lu
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Tingting Qian
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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16
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Xiao K, Abbt-Braun G, Horn H. Changes in the characteristics of dissolved organic matter during sludge treatment: A critical review. WATER RESEARCH 2020; 187:116441. [PMID: 33022515 DOI: 10.1016/j.watres.2020.116441] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/16/2020] [Accepted: 09/19/2020] [Indexed: 06/11/2023]
Abstract
Dissolved organic matter (DOM) of sludge is a heterogeneous mixture of high to low molecular weight organic substances which is including proteinaceous compounds, carbohydrates, humic substances, lipids, lignins, organic acids, organic micropollutants and other biological derived substances generated during wastewater treatment. This paper reviews definition, composition, quantification, and transformation of DOM during different sludge treatments, and the complex interplay of DOM with microbial communities. In anaerobic digestion, anaerobic digestion-refractory organic matter, particularly compounds showing polycyclic steroid-like, alkane and aromatic structures can be generated after pretreatment. During dewatering, the DOM fraction of low molecular weight proteins (< 20,000 Dalton) is the key parameter deteriorating sludge dewaterability. During composting, decomposition and polymerization of DOM occur, followed by the formation of humic substances. During landfill treatment, the composition of DOM, particularly humic substances, are related with leachate quality. Finally, suggestions are proposed for a better understanding of the transformation and degradation of DOM during sludge treatment. Future work in sludge studies needs the establishment and implementation of definitions for sample handling and the standardization of DOM methods for analysis, including sample preparation and fractionation, and data integration. A more detailed knowledge of DOM in sludge facilitates the operation and optimization of sludge treatment technologies.
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Affiliation(s)
- Keke Xiao
- School of Environmental Science & Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan, Hubei 430074, China; Engler-Bunte-Institut, Water Chemistry and Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany; DVGW Research Laboratories, Water Chemistry and Water Technology, Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany
| | - Gudrun Abbt-Braun
- Engler-Bunte-Institut, Water Chemistry and Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany
| | - Harald Horn
- Engler-Bunte-Institut, Water Chemistry and Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany; DVGW Research Laboratories, Water Chemistry and Water Technology, Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany.
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Wang Y, Tian F, Guo P, Fu D, Heeres HJ, Tang T, Yuan H, Wang B, Li J. Catalytic liquefaction of sewage sludge to small molecular weight chemicals. Sci Rep 2020; 10:18929. [PMID: 33144686 PMCID: PMC7609695 DOI: 10.1038/s41598-020-75980-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 10/19/2020] [Indexed: 11/09/2022] Open
Abstract
The catalytic hydrotreatment of sewage sludge, the wet solid byproducts from wastewater treatment plants, using supported Ir, Pt, Pd, Ru catalysts had been investigated with different solvent conditions. Reactions were carried out in a batch set-up at elevated temperatures (400 °C) using a hydrogen donor (formic acid (FA) in isopropanol (IPA) or hydrogen gas), with sewage sludge obtained from different sampling places. Sewage sludge conversions of up to 83.72% were achieved using Pt/C, whereas the performance for the others catalysts is different and solvent had a strong effect on the conversion rate and product constitution. The sewage sludge oils were characterised using a range of analytical techniques (GC, GC-MS, GCxGC, GPC) and were shown to consist of monomers, mainly alkanes and higher oligomers.
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Affiliation(s)
- Yuehu Wang
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China. .,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China.
| | - Feihong Tian
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
| | - Peimei Guo
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
| | - Dazhen Fu
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
| | - Hero Jan Heeres
- Chemical Engineering Department, ENTEG, University of Groningen, Nijenborg 4, 9747 AG, Groningen, The Netherlands
| | - Taotao Tang
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
| | - Huayu Yuan
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
| | - Bing Wang
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
| | - Jiang Li
- College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.,Observation and Research Station for Guizhou Karst Environmental Ecosystems, Guiyang, 550025, China
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Liang J, Zhang L, Yan W, Zhou Y. Mechanistic insights into a novel nitrilotriacetic acid-Fe 0 and CaO 2 process for efficient anaerobic digestion sludge dewatering at near-neutral pH. WATER RESEARCH 2020; 184:116149. [PMID: 32750584 DOI: 10.1016/j.watres.2020.116149] [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: 05/25/2020] [Revised: 06/29/2020] [Accepted: 07/03/2020] [Indexed: 06/11/2023]
Abstract
Traditional Fenton or Fenton-like oxidation has been widely studied for waste activated sludge dewaterability. However, the narrow pH range (2.0-4.0) and the instabilities of Fe2+ and H2O2 have hindered its commercial application. Owing to the high alkalinity of anaerobic digestion (AD) sludge, traditional Fenton or Fenton-like oxidation is economically unfeasible for its dewatering. In this study, we successfully demonstrated a novel and feasible method that used nitrilotriacetic acid (NTA)-Fe0 combined with CaO2 (NTA-Fe0/CaO2) at near-neutral pH (∼6.0) (a slight pH adjustment) in which capillary suction time ratio (CST0/CST) and centrifuged weight reduction (CWR) improved by 6 folds and 42.98 ± 0.37%, respectively, under the optimal conditions. The presence of NTA accelerated the Fe0 corrosion, Fe2+ stability and turnover between Fe2+ and Fe3+. As such, Fe0 could effectively catalyze CaO2 to produce hydroxyl radicals (•OH) under near-neutral conditions. Accordingly, various molecular weight hydrophilic compounds in different extracellular polymeric substances fractions were significantly reduced after treatment. The hydrophilic functional groups especially protein molecules were largely reduced. Consequently, the viscosity of sludge and particle size effectively decreased, while the release of bound water, surface charge, flocculation, and flowability of sludge were improved. The cost-benefit analysis further demonstrated the NTA-Fe0/CaO2 treatment has high reusability and stability and is also more economical over the FeCl3/CaO and Fenton's reagent/CaO treatments. In summary, the NTA-Fe0/CaO2 process is a cost-effective and practically feasible technology for improving AD sludge dewaterability.
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Affiliation(s)
- Jialin Liang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore; School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Liang Zhang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - Wangwang Yan
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - 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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19
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Jeon D, Chung K, Shin J, Min Park C, Gu Shin S, Mo Kim Y. Reducing food waste in residential complexes using a pilot-scale on-site system. BIORESOURCE TECHNOLOGY 2020; 311:123497. [PMID: 32408195 DOI: 10.1016/j.biortech.2020.123497] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/03/2020] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
A pilot-scale on-site system combining biological treatment and a drying stage was applied to achieve mass reduction of food waste (FW) at an urban residential complex. The effectiveness of biodegrading the organic portion of FW via microorganisms existing in FW improved by 38.80% by controlling rates of FW loading and air-flow. In one stage of the on-site biological treatment, the major bacterial community was identified to be mesophilic and facultative; Lactobacillus was the most dominant genus, accounting for 78.1% of bacterial community. Total mass reduction of FW approached 90.15% by increasing removal of both moisture and the organic portion of FW. In addition, the solids and liquids of the final by-products have the potential to be recycled into resources such as fertilizer, a bio-solid refuse fuel or external carbon sources for wastewater treatment plants. The proposed decentralized system offers practical and environmental approaches for FW management in residential complexes.
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Affiliation(s)
- Dawoon Jeon
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Buk-gu, Gwangju 500-712, Republic of Korea
| | - Kyungmi Chung
- GS E&C Research Institute, Building & Environment Research Team, 388,Baeok-daero Idong-myeon, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Jingyeong Shin
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Chang Min Park
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Seung Gu Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, Jinju 52725, Republic of Korea
| | - Young Mo Kim
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea.
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