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Liu K, Lv L, Li W, Wang X, Han M, Ren Z, Gao W, Wang P, Liu X, Sun L, Zhang G. Micro-aeration and leachate recirculation for the acceleration of landfill stabilization: Enhanced hydrolytic acidification by facultative bacteria. BIORESOURCE TECHNOLOGY 2023; 387:129615. [PMID: 37544542 DOI: 10.1016/j.biortech.2023.129615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/26/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
The long duration of landfill stabilization is one of the challenges faced by municipalities. In this paper, a combination of micro-aeration and leachate recirculation is used to achieve rapid degradation of organic matter in landfill waste. The results showed that the content of volatile fatty acids (VFAs) in the hydrolysis phase increased significantly and could enter the methanogenic phase quickly. Until the end of the landfill, the removal rates of chemical oxygen demand (COD), total phosphorus (TP) and ammonia nitrogen (NH4+-N) by micro-aeration and leachate recirculation reached 80.17 %, 48.30 % and 48.56 %, respectively, and the organic matter degradation rate reached 50 %. Micro-aeration and leachate recirculation enhanced the abundance of facultative hydrolytic bacteria such as Rummeliibacillus and Bacillus and the oxygen tolerance of Methanobrevibacter and Methanoculleus. Micro-aeration and leachate recirculation improved the organic matter degradation efficiency of landfill waste by promoting the growth of functional microorganisms.
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Affiliation(s)
- Kaili Liu
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Longyi Lv
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090, PR China
| | - Xinyuan Wang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Muda Han
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Zhijun Ren
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Wenfang Gao
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Pengfei Wang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Xiaoyang Liu
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Li Sun
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Guangming Zhang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
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Jiang S, Yu D, Xiong F, Lian X, Jiang X. Enhanced methane production from the anaerobic co-digestion of food waste plus fruit and vegetable waste. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-27328-z. [PMID: 37155098 DOI: 10.1007/s11356-023-27328-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 04/26/2023] [Indexed: 05/10/2023]
Abstract
Food waste (FW) and fruit, vegetable waste (FVW) are important components of municipal solid waste, yet the performance and related mechanisms of anaerobic co-digestion of FW and FVW for methane production have been rarely investigated. In order to get a deeper understanding of the mechanisms involved, the mesophilic FW and FVW anaerobic co-digestion in different proportions was investigated. The experimental results showed that when the ratio of FW and FVW was 1/1 (in terms of volatile suspended solid), the maximum biomethane yield of 269.9 mL/g TCOD from the codigested substrate is significantly higher than that in FW or FVW anaerobic digestion alone. FW and FVW co-digestion promoted the dissolution and biotransformation of organic matter. When the recommended mixing ratio was applied, the maximum concentration of dissolved chemical oxygen demand (COD) was high as 11971 mg/L. FW and FVW co-digestion reduced the accumulation of volatile fatty acids (VFA) in the digestive system, thus reducing its negative impact on the methanogenesis process. FW and FVW co-digestion process synergistically enhanced microbial activity. The analysis of microbial population structure showed that when FW and FVW were co-digested at the recommended ratio, the relative abundance of Proteiniphilum increased to 26.5%, and the relative abundances of Methanosaeta and Candidatus Methanofastidiosum were also significantly increased. The results of this work provide a certain amount of theoretical basis and technical support for the co-digestion of FW and FVW.
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Affiliation(s)
- Shangsong Jiang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
| | - Dan Yu
- Qingdao Municipal Engineering Design and Research Institute, Qingdao, 266101, China
| | - Fei Xiong
- Qingdao Shunqingyuan Environment Co., Ltd., Qingdao, 266109, China
| | - Xiaoying Lian
- Qingdao Sunrui Marine Environment Co., Ltd., Qingdao, 266101, China
| | - Xiuyan Jiang
- Qingdao Municipal Engineering Design and Research Institute, Qingdao, 266101, China
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3
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Zhou Z, Wang Y, Wang M, Zhou Z. Co-metabolic Effect of Glucose on Methane Production and Phenanthrene Removal in an Enriched Phenanthrene-Degrading Consortium Under Methanogenesis. Front Microbiol 2021; 12:749967. [PMID: 34712215 PMCID: PMC8546250 DOI: 10.3389/fmicb.2021.749967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/16/2021] [Indexed: 11/13/2022] Open
Abstract
Anaerobic digestion is used to treat diverse waste classes, and polycyclic aromatic hydrocarbons (PAHs) are a class of refractory compounds that common in wastes treated using anaerobic digestion. In this study, a microbial consortium with the ability to degrade phenanthrene under methanogenesis was enriched from paddy soil to investigate the cometabolic effect of glucose on methane (CH4) production and phenanthrene (a representative PAH) degradation under methanogenic conditions. The addition of glucose enhanced the CH4 production rate (from 0.37 to 2.25mg⋅L-1⋅d-1) but had no influence on the degradation rate of phenanthrene. Moreover, glucose addition significantly decreased the microbial α-diversity (from 2.59 to 1.30) of the enriched consortium but showed no significant effect on the microbial community (R 2=0.39, p=0.10), archaeal community (R 2=0.48, p=0.10), or functional profile (R 2=0.48, p=0.10). The relative abundance of genes involved in the degradation of aromatic compounds showed a decreasing tendency with the addition of glucose, whereas that of genes related to CH4 synthesis was not affected. Additionally, the abundance of genes related to the acetate pathway was the highest among the four types of CH4 synthesis pathways detected in the enriched consortium, which averagely accounted for 48.24% of the total CH4 synthesis pathway, indicating that the acetate pathway is dominant in this phenanthrene-degrading system during methanogenesis. Our results reveal that achieving an ideal effect is diffcult via co-metabolism in a single-stage digestion system of PAH under methanogenesis; thus, other anaerobic systems with higher PAH removal efficiency should be combined with methanogenic digestion, assembling a multistage pattern to enhance the PAH removal rate and CH4 production in anaerobic digestion.
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Affiliation(s)
- Ziyan Zhou
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Yanqin Wang
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Mingxia Wang
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Zhifeng Zhou
- College of Resources and Environment, Southwest University, Chongqing, China
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4
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Two Phase Anaerobic Digestion System of Municipal Solid Waste by Utilizing Microaeration and Granular Activated Carbon. ENERGIES 2020. [DOI: 10.3390/en13040933] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In an anaerobic digestion (AD) process, the hydrolysis phase is often limited when substrates with high concentrations of solids are used. We hypothesized that applying micro-aeration in the hydrolysis phase and the application of granular activated carbon (GAC) in the methanogenesis phase could make the AD process more efficient. A packed bed reactor (PBR) coupled with an up-flow anaerobic sludge blanket (UASB) was conducted, and its effects on methane generation were evaluated. The micro-aeration rate applied in PBR was 254 L-air/kg-Total solids (TS)-d was compared with a control reactor. Micro-aeration showed that it reduced the hydrolysis time and increased the organic matter solubilization as chemical oxygen demand (COD) increasing 200%, with a volatile fatty acids (VFAs) increment higher than 300%, compared to the control reactor (without aeration). Our findings revealed that the implementations of microaeration and GAC in the two-phase AD system could enhance methane production by reducing hydrolysis time, increasing solid waste solubilization.
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Luo L, Wong JWC. Enhanced food waste degradation in integrated two-phase anaerobic digestion: Effect of leachate recirculation ratio. BIORESOURCE TECHNOLOGY 2019; 291:121813. [PMID: 31376669 DOI: 10.1016/j.biortech.2019.121813] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 07/12/2019] [Accepted: 07/13/2019] [Indexed: 06/10/2023]
Abstract
The aim of this study is to evaluate the effect of leachate recirculation at a ratio of 0%, 25%, 50% or 75% of collected leachate from the Leach Bed Reactor (LBR) on food waste digestion efficiency and its subsequent methane production in the second phase of a two-phase anaerobic system. Higher hydrolysis-acidogenesis efficiency and lower energy loss were achieved in LBR with higher leachate recirculation ratio. Better biochemical balance between metabolic products and microorganisms in leachate was revealed under 50% leachate recirculation ratio, which leads to the highest hydrogen production yield in LBR resulting the highest methane production yield in the corresponding methanogenic phase which was at least 15% higher than that in other conditions. This provides an easy approach to enhance the hydrolysis efficiency and in the same time a biochemical balanced leachate to enhance methanogenic reaction of a two-phase anaerobic digestion.
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Affiliation(s)
- Liwen Luo
- Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region
| | - Jonathan W C Wong
- Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region.
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Digan L, Horgue P, Debenest G, Dubos S, Pommier S, Paul E, Dumas C. An improved hydrodynamic model for percolation and drainage dynamics for household and agricultural waste beds. WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 98:69-80. [PMID: 31437712 DOI: 10.1016/j.wasman.2019.07.027] [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: 10/31/2018] [Revised: 07/17/2019] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
This study focuses on the hydrodynamic modelling of percolation and drainage cycles in the context of solid-state anaerobic digestion and fermentation (VFA platform) of household solid wastes (HSW) in leach bed reactors. Attention was given to the characterization of the water distribution and hydrodynamic properties of the beds. The experimental procedure enabled the measurement of water content in waste beds at different states of compaction during injection and drainage, and this for two types of HSW and for two other type of wastes. A numerical model, set up with experimental data from water content measurements, highlighted that a capillary-free dual-porosity model was not able to correctly reproduce all the hydrodynamic features and particularly the drainage dynamics. The model was improved by adding a reservoir water fraction to macroporosity which allowed to correctly simulate dynamics. This model, validated with data obtained from agricultural wastes, enabled to explain more precisely the water behaviour during percolation processes and these results should be useful for driving either solid-state anaerobic digestion or fermentation reactors. Indeed, this implies that the recirculation regime will impact the renewal of the immobile water fraction in macroporosity, inducing different concentration levels of fermentation products in the leachate.
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Affiliation(s)
- Laura Digan
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Pierre Horgue
- INPT, UPS, IMFT (Institut de Mécanique des Fluides de Toulouse), Université de Toulouse, Allée Camille Soula, F-31400 Toulouse, France and CNRS, IMFT, F-31400 Toulouse, France
| | - Gérald Debenest
- INPT, UPS, IMFT (Institut de Mécanique des Fluides de Toulouse), Université de Toulouse, Allée Camille Soula, F-31400 Toulouse, France and CNRS, IMFT, F-31400 Toulouse, France
| | - Simon Dubos
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | | | - Etienne Paul
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Claire Dumas
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France.
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7
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Kainthola J, Kalamdhad AS, Goud VV. A review on enhanced biogas production from anaerobic digestion of lignocellulosic biomass by different enhancement techniques. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.05.023] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Ryue J, Lin L, Liu Y, Lu W, McCartney D, Dhar BR. Comparative effects of GAC addition on methane productivity and microbial community in mesophilic and thermophilic anaerobic digestion of food waste. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.03.010] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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9
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Zhou H, Wen Z. Solid-State Anaerobic Digestion for Waste Management and Biogas Production. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2019; 169:147-168. [PMID: 30796502 DOI: 10.1007/10_2019_86] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Solid-state anaerobic digestion (SS-AD) is commonly used to treat feedstocks with high solid content such as municipal solid waste and lignocellulosic biomass. Compared to liquid state anaerobic digestion (LS-AD), SS-AD has multiple advantages including high organic loading, minimal digestate generated, and low energy requirement for heating. However, the main disadvantages limiting the efficiency of SS-AD are long solid retention time, incomplete mixing, and an accumulation of inhibitors. For a successful and efficient SS-AD, it is important to control operation parameters such as nutrient levels, C/N ratio, feedstock-to-inoculum ratio, pH, temperature, and mixing. Biogas production in SS-AD performance can be enhanced by feedstock pretreatment, co-digestion, and supplement of additives such as biochar. The aim of this chapter is to provide a comprehensive summary of the current development in SS-AD as an effective way for treating solid waste materials. Graphical Abstract.
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Affiliation(s)
- Haoqin Zhou
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, USA
| | - Zhiyou Wen
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, USA.
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10
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Xiong Z, Hussain A, Lee J, Lee HS. Food waste fermentation in a leach bed reactor: Reactor performance, and microbial ecology and dynamics. BIORESOURCE TECHNOLOGY 2019; 274:153-161. [PMID: 30502606 DOI: 10.1016/j.biortech.2018.11.066] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/15/2018] [Accepted: 11/18/2018] [Indexed: 06/09/2023]
Abstract
Food waste fermentation was investigated in a leach bed reactor operated at acidic, neutral and alkaline conditions. Highest solids reduction of 87% was obtained at pH 7 in 14 days of reaction time with minimum mixing. The concentration of volatile fatty acids increased to 28.6 g COD/L under pH 7, while the highest butyric acid of 16 g COD/L was obtained at pH 6. Bacterial community structure was narrowed down to Bifidobacterium and Clostridium at pH 6, while Bacteroides and Dysgonomonas were identified as main players at both pH 7 and 8. Bacterial populations in the food residue generally reflected those in the leachate, but some bacteria were selectively enriched in the leachate or the food residue. Bacterial community dynamics suggested that biodegradable food waste was first fermented by one of dominant players (e.g., Clostridium) and the other degraded resistant dietary fibers later (e.g., Bifidobacterium, Bacteroides, Dysgonomonas).
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Affiliation(s)
- Ziyi Xiong
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Ontario N2L3G1, Canada
| | - Abid Hussain
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Ontario N2L3G1, Canada; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Jangho Lee
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Ontario N2L3G1, Canada
| | - Hyung-Sool Lee
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Ontario N2L3G1, Canada.
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11
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Wu C, Huang Q, Yu M, Ren Y, Wang Q, Sakai K. Effects of digestate recirculation on a two-stage anaerobic digestion system, particularly focusing on metabolite correlation analysis. BIORESOURCE TECHNOLOGY 2018; 251:40-48. [PMID: 29268149 DOI: 10.1016/j.biortech.2017.12.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 12/06/2017] [Accepted: 12/07/2017] [Indexed: 05/21/2023]
Abstract
Single-stage (S-N treatment) and two-stage anaerobic digestion with (T-R treatment) and without digestate recirculation (T-N treatment) for methane production using food waste (FW) were comparatively evaluated to examine the effects of digestate recirculation on anaerobic digestion (AD). Digestate recirculation positively affected the methane yield and organic loading rate (OLR). Metabolite correlation analysis revealed that a systematic hydrolysis degree of greater than 75% is crucial to achieve the complete recoverable yield of methane from FW. Digestate recirculation also markedly increased the system alkalinity, maintaining an optimum pH for methanogens. However, the ammonium accumulated by T-R treatment would destroy the metabolic balance between the hydrolytic bacteria and methanogens, especially at a critical OLR. Therefore, the appropriate control of two-stage AD systems with digestate recirculation is limited not only to OLR regulation but also to the prevention of ammonium accumulation.
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Affiliation(s)
- Chuanfu Wu
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 10083, China
| | - Qiqi Huang
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
| | - Miao Yu
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
| | - Yuanyuan Ren
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
| | - Qunhui Wang
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China; Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 10083, China.
| | - Kenji Sakai
- Department of Bioscience and Biotechnology, Faculty of Agriculture Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
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12
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Gu XY, Liu JZ, Wong JWC. Control of lactic acid production during hydrolysis and acidogenesis of food waste. BIORESOURCE TECHNOLOGY 2018; 247:711-715. [PMID: 30060404 DOI: 10.1016/j.biortech.2017.09.166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/20/2017] [Accepted: 09/23/2017] [Indexed: 06/08/2023]
Abstract
Lactate accumulation occurs frequently during the hydrolysis and acidogenesis of food waste and produces an unfavorable substrate for anaerobic digestion. The objective of the present study was to reduce lactic acid production during the hydrolysis and acidogenesis of food waste in leachate bed reactor for establishment of the two-phase anaerobic digestion system. The results showed that the hydrolysis and acidogenesis of food waste in batch feeding mode underwent two consecutive stages, namely lactic acid fermentation and mixed acid fermentation. In the lactic acid fermentation stage, lactate constituted 74.4-96.8% of the total organic acids in the leachate. However in semi-continuous mode the content of lactate in the leachate could be reduced less than 0-2% for leach bed reactors operated at feeding loads of 50-150g/d although lactate accumulation occurred at a feeding load of 200g/d. Furthermore the organic acid shifted to acetate and butyrate, providing ideal substrates for anaerobic digestion.
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Affiliation(s)
- X Y Gu
- College of Life Sciences/Key Laboratory of Microbiological Engineering of Agricultural Environments, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, PR China.
| | - J Z Liu
- College of Life Sciences/Key Laboratory of Microbiological Engineering of Agricultural Environments, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, PR China
| | - J W C Wong
- Sino-Forest Applied Research Center for Pearl Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region
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Ratanatamskul C, Saleart T. Effects of sludge recirculation rate and mixing time on performance of a prototype single-stage anaerobic digester for conversion of food wastes to biogas and energy recovery. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:7092-8. [PMID: 25864735 DOI: 10.1007/s11356-015-4448-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 03/25/2015] [Indexed: 05/28/2023]
Abstract
Food wastes have been recognized as the largest waste stream and accounts for 39.25 % of total municipal solid waste in Thailand. Chulalongkorn University has participated in the program of in situ energy recovery from food wastes under the Ministry of Energy (MOE), Thailand. This research aims to develop a prototype single-stage anaerobic digestion system for biogas production and energy recovery from food wastes inside Chulalongkorn University. Here, the effects of sludge recirculation rate and mixing time were investigated as the main key parameters for the system design and operation. From the results obtained in this study, it was found that the sludge recirculation rate of 100 % and the mixing time of 60 min per day were the most suitable design parameters to achieve high efficiencies in terms of chemical oxygen demand (COD), total solids (TS), and total volatile solid (TVS) removal and also biogas production by this prototype anaerobic digester. The obtained biogas production was found to be 0.71 m(3)/kg COD and the composition of methane was 61.6 %. Moreover, the efficiencies of COD removal were as high as 82.9 % and TVS removal could reach 83.9 % at the optimal condition. Therefore, the developed prototype single-stage anaerobic digester can be highly promising for university canteen application to recover energy from food wastes via biogas production.
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Affiliation(s)
- Chavalit Ratanatamskul
- Department of Environmental Engineering, Chulalongkorn University, Bangkok, 10330, Thailand.
| | - Tawinan Saleart
- Inter-Department of Environmental Science, Chulalongkorn University, Bangkok, 10330, Thailand
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14
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Anaerobic Leaching-Bed Reactor Treating Food Waste for Organic Acid Production: Effect of Bulking Agent. ACTA ACUST UNITED AC 2015. [DOI: 10.4028/www.scientific.net/amm.768.289] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Food waste was a troublesome organic waste stream, but a highly desirable substrate for anaerobic digestion to recover energy. Among the diverse reactor configurations, the leaching-bed reactor was reported to be best choice to treating the particular organic waste for platform compounds (volatile fatty acid). In this study, we carried out a series of experiments to investigate the bulking agent and pH control on process performance, and special focus was put on the biodegradability of bulking agent. The supplement of bulking agent greatly improved the leaching rate by 3.6 folds. Although the hydrolytic and acidogenic bacteria were resistant to low pH, the pH control (neutralization) caused a significantly increased volatile fatty acid (VFA) productions from 39.1 g COD/kg VSaddedto 183.4 g VFA/kg VSadded. Comparing with the undegradable bulking agent, the case with supplementing corncob as a bulking agent showed superior VFA yields (225 g COD/kg VSadded) which could be ascribed to the good adhesive properties for microorganisms and biodegradability. The ultimate analysis of the substrate (excluding the bulking agent) also showed that most of food waste was degraded with relative short reaction time. In addition, the TG/DTA and FTIR of residual corncob results indicated some components (cellulose, hemi-cellulose) were degraded, which could contribute to the additional VFA production (14 g COD/kg VSadded). This study suggested that the corncob could be considered as a good bio-compatible bulking agent for leaching-bed reactor, which not only increased the VFA productivity, but provided additional VFA production.
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15
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Mekjinda N, Ritchie RJ. Breakdown of food waste by anaerobic fermentation and non-oxygen producing photosynthesis using a photosynthetic bacterium. WASTE MANAGEMENT (NEW YORK, N.Y.) 2015; 35:199-206. [PMID: 25465509 DOI: 10.1016/j.wasman.2014.10.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 10/20/2014] [Accepted: 10/20/2014] [Indexed: 06/04/2023]
Abstract
Large volumes of food waste are produced by restaurants, hotels, etc generating problems in its collection, processing and disposal. Disposal as garbage increases the organic matter in landfills and leachates. The photosynthetic bacterium Rhodopseudomonas palustris (CGA 009) easily broke down food waste. R. palustris produces H2 under anaerobic conditions and digests a very wide range of organic compounds. R. palustris reduced BOD by ≈70% and COD by ≈33%, starch, ammonia, nitrate, was removed but had little effect on reducing sugar or the total phosphorus, lipid, protein, total solid in a 7-day incubation. R. palustris produced a maximum of 80ml H2/g COD/day. A two-stage anaerobic digestion using yeast as the first stage, followed by a R. palustris digestion was tested but production of H2 was low.
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Affiliation(s)
- N Mekjinda
- Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus, Kathu, Phuket 83120, Thailand
| | - R J Ritchie
- Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus, Kathu, Phuket 83120, Thailand.
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16
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Xu SY, Karthikeyan OP, Selvam A, Wong JWC. Microbial community distribution and extracellular enzyme activities in leach bed reactor treating food waste: effect of different leachate recirculation practices. BIORESOURCE TECHNOLOGY 2014; 168:41-48. [PMID: 24972915 DOI: 10.1016/j.biortech.2014.05.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/30/2014] [Accepted: 05/03/2014] [Indexed: 06/03/2023]
Abstract
This study aimed at understanding the relationship between microbial community and extracellular enzyme activities of leach bed reactor (LBR) treating food waste under different leachate recirculation practices (once per day and continuous) and liquid to solid (L/S) ratios (1:1 and 0.5:1). Microbial community analysis using PCR-DGGE revealed that Lactobacillus sp., Bifidobacter sp., and Proteobacteria were the most abundant species. Number of phylotypes was higher in LBRs with intermittent recirculation; whereas, lower number of phylotypes dominated by the key players of degradation was observed with continuous recirculation. The L/S ratio of 1:1 significantly enhanced the volatile solids removal compared with 0.5:1; however, this effect was insignificant under once a day leachate recirculation. Continuous leachate recirculation with 1:1 L/S ratio significantly improved the organic leaching (240 g COD/kgvolatile solid) and showed distinct extracellular enzyme activities suitable for food waste acidogenesis.
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Affiliation(s)
- Su Yun Xu
- Department of Environmental & Low-Carbon Science, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, China; Sino-Forest Applied Research Centre for Pearl River Delta Environment and Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region
| | - Obuli P Karthikeyan
- Sino-Forest Applied Research Centre for Pearl River Delta Environment and Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region; School of Marine and Tropical Biology, Faculty of Engineering, James Cook University, Townsville, Queensland, Australia
| | - Ammaiyappan Selvam
- Sino-Forest Applied Research Centre for Pearl River Delta Environment and Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region
| | - Jonathan W C Wong
- Sino-Forest Applied Research Centre for Pearl River Delta Environment and Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region.
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17
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Yan BH, Selvam A, Wong JWC. Application of rumen microbes to enhance food waste hydrolysis in acidogenic leach-bed reactors. BIORESOURCE TECHNOLOGY 2014; 168:64-71. [PMID: 24785786 DOI: 10.1016/j.biortech.2014.03.085] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 03/14/2014] [Accepted: 03/17/2014] [Indexed: 06/03/2023]
Abstract
Effect of rumen microorganisms on hydrolysis of food waste in leach bed reactor (LBR) was investigated. LBRs were inoculated (20%, w/w) with cow manure and anaerobically digested sludge at different ratios, 0:1 (LBR-A), 1:3 (LBR-B), 1:1 (LBR-C), 3:1 (LBR-D) and 1:0 (LBR-E). High volatile solids (VS) conversion efficiency of 68% was achieved in LBR-E. Compared with LBR-A, chemical oxygen demand, total soluble products and total Kjeldahl nitrogen leaching of LBR-E were increased by 16%, 14.3% and 27%, respectively. Recovery of the highest amounts of ethanol and butyrate in LBR-E indicated that the metabolic pathway mediated by rumen microorganisms was favorable for subsequent methanogenesis. Phylogenetic analysis confirmed that the enhanced hydrolysis in LBR-E was mainly due to strong degraders, e.g. Enterobacter, Bifidobacterium thermacidophilum and Caloramator sourced from cow manure. Results demonstrate that rumen microorganisms rapidly degrade the VS and produce useful VFAs with high methane yields in subsequent methanogenesis.
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Affiliation(s)
- Bing Hua Yan
- Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region, PR China
| | - Ammaiyappan Selvam
- Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region, PR China
| | - Jonathan W C Wong
- Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region, PR China.
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18
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Ganesh R, Torrijos M, Sousbie P, Lugardon A, Steyer JP, Delgenes JP. Single-phase and two-phase anaerobic digestion of fruit and vegetable waste: comparison of start-up, reactor stability and process performance. WASTE MANAGEMENT (NEW YORK, N.Y.) 2014; 34:875-885. [PMID: 24679584 DOI: 10.1016/j.wasman.2014.02.023] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/12/2014] [Accepted: 02/21/2014] [Indexed: 06/03/2023]
Abstract
Single-phase and two-phase digestion of fruit and vegetable waste were studied to compare reactor start-up, reactor stability and performance (methane yield, volatile solids reduction and energy yield). The single-phase reactor (SPR) was a conventional reactor operated at a low loading rate (maximum of 3.5 kgVS/m3 d), while the two-phase system consisted of an acidification reactor (TPAR) and a methanogenic reactor (TPMR). The TPAR was inoculated with methanogenic sludge similar to the SPR, but was operated with step-wise increase in the loading rate and with total recirculation of reactor solids to convert it into acidification sludge. Before each feeding, part of the sludge from TPAR was centrifuged, the centrifuge liquid (solubilized products) was fed to the TPMR and centrifuged solids were recycled back to the reactor. Single-phase digestion produced a methane yield of 0.45 m3 CH4/kg VS fed and VS removal of 83%. The TPAR shifted to acidification mode at an OLR of 10.0 kgVS/m3 d and then achieved stable performance at 7.0 kgVS/m3 d and pH 5.5-6.2, with very high substrate solubilization rate and a methane yield of 0.30 m3 CH4/kg COD fed. The two-phase process was capable of high VS reduction, but material and energy balance showed that the single-phase process was superior in terms of volumetric methane production and energy yield by 33%. The lower energy yield of the two-phase system was due to the loss of energy during hydrolysis in the TPAR and the deficit in methane production in the TPMR attributed to COD loss due to biomass synthesis and adsorption of hard COD onto the flocs. These results including the complicated operational procedure of the two-phase process and the economic factors suggested that the single-phase process could be the preferred system for FVW.
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Affiliation(s)
- Rangaraj Ganesh
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne F-11100, France
| | - Michel Torrijos
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne F-11100, France.
| | - Philippe Sousbie
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne F-11100, France
| | - Aurelien Lugardon
- Naskeo Environnment, 52 rue Paul Vaillant Couturier, F-92240 Malakoff, France
| | - Jean Philippe Steyer
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne F-11100, France
| | - Jean Philippe Delgenes
- INRA, UR50, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne F-11100, France
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19
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Li X, Chen Y, Zhao S, Wang D, Zheng X, Luo J. Lactic acid accumulation from sludge and food waste to improve the yield of propionic acid-enriched VFA. Biochem Eng J 2014. [DOI: 10.1016/j.bej.2013.12.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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Bai J, Xu H, Zhang Y, Peng Z, Xu G. Combined industrial and domestic wastewater treatment by periodic allocating water hybrid hydrolysis acidification reactor followed by SBR. Biochem Eng J 2013. [DOI: 10.1016/j.bej.2012.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Xu SY, Karthikeyan OP, Selvam A, Wong JWC. Effect of inoculum to substrate ratio on the hydrolysis and acidification of food waste in leach bed reactor. BIORESOURCE TECHNOLOGY 2012; 126:425-30. [PMID: 22227144 DOI: 10.1016/j.biortech.2011.12.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 12/11/2011] [Accepted: 12/12/2011] [Indexed: 05/14/2023]
Abstract
The aim of present study was to determine an appropriate ISR (inoculum to substrate ratio) to enhance the hydrolysis rate and reduce the solid retention time of food waste in hydrolytic-acidogenesis leach bed reactor (LBR). LBR 1-4 were inoculated with 0%, 5%, 20% and 80% (w/w basis) of anaerobically digested sludge, respectively, using artificial food waste as substrate. Experiments were conducted in batch mode at mesophilic condition (35 °C) for 17 days. Higher ISR resulted in 4.3-fold increase in protein hydrolysis; whereas, only a modest increase in the decomposition of carbohydrate. Two kinetic models for carbohydrate and protein degradation were proposed and evaluated. The differences among four ISRs in volatile solids removal efficiencies were marginal, i.e. 52.4%, 62.8%, 63.2% and 71.7% for LBR 1-4, respectively; indicating that higher ISR was insignificant in enhancing the overall hydrolysis rate in LBR. Therefore, a lower ISR of 20% was recommended in the hydrolytic-acidogenic process.
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Affiliation(s)
- Su Yun Xu
- Sino-Forest Applied Research Center for Pearl River Delta Environment and Department of Biology, Hong Kong Baptist University, Hong Kong, Hong Kong Special Administrative Region
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22
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Xie S, Lawlor PG, Frost JP, Wu G, Zhan X. Hydrolysis and acidification of grass silage in leaching bed reactors. BIORESOURCE TECHNOLOGY 2012; 114:406-413. [PMID: 22459960 DOI: 10.1016/j.biortech.2012.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/28/2012] [Accepted: 03/02/2012] [Indexed: 05/31/2023]
Abstract
Hydrolysis and acidification of grass silage (GS) was examined in leaching bed reactors (LBRs) under organic loading rates (OLRs) of 0.5, 0.8 and 1.0 kg volatile solids (VS)/m(3)/day. The LBRs were run in duplicate over five consecutive batch tests (Batch tests 1-5) to examine the effects of pH, leachate dilution and addition of inoculum on the process of hydrolysis and acidification. The highest GS hydrolysis yields of 52-58%, acidification yields of 57-60% and VS removals of 62-66% were obtained in Batch test 4. Increasing OLRs affected the hydrolysis yield negatively. In Batch test 4, the reduction of lignocellulosic materials was up to 74.4% of hemicellulose, 30.1% of cellulose and 9.3% of lignin within 32 days. Cellulase activity can be used as an indicator for the hydrolysis process. Methane production from the LBRs only accounted for 10.0-13.8% of the biological methane potential of GS.
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Affiliation(s)
- S Xie
- Civil Engineering, College of Engineering and Informatics and Ryan Institute, National University of Ireland, Galway, Ireland
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23
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Zhang L, Ouyang W, Lia A. Essential Role of Trace Elements in Continuous Anaerobic Digestion of Food Waste. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.proenv.2012.10.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Xu SY, Lam HP, Karthikeyan OP, Wong JWC. Optimization of food waste hydrolysis in leach bed coupled with methanogenic reactor: effect of pH and bulking agent. BIORESOURCE TECHNOLOGY 2011; 102:3702-3708. [PMID: 21195606 DOI: 10.1016/j.biortech.2010.11.095] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 11/19/2010] [Accepted: 11/22/2010] [Indexed: 05/30/2023]
Abstract
The effects of pH and bulking agents on hydrolysis/acidogenesis of food waste were studied using leach bed reactor (LBR) coupled with methanogenic up-flow anaerobic sludge blanket (UASB) reactor. The hydrolysis rate under regulated pH (6.0) was studied and compared with unregulated one during initial experiment. Then, the efficacies of five different bulking agents, i.e. plastic full particles, plastic hollow sphere, bottom ash, wood chip and saw dust were experimented under the regulated pH condition. Leachate recirculation with 50% water replacement was practiced throughout the experiment. Results proved that the daily leachate recirculation with pH control (6.0) accelerated the hydrolysis rate (59% higher volatile fatty acids) and methane production (up to 88%) compared to that of control without pH control. Furthermore, bottom ash improved the reactor alkalinity, which internally buffered the system that improved the methane production rate (0.182 l CH(4)/g VS(added)) than other bulking agents.
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Affiliation(s)
- Su Yun Xu
- Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong SAR, Hong Kong
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25
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Li D, Zhou T, Chen L, Jiang W, Cheng F, Li B, Kitamura Y. Using porphyritic andesite as a new additive for improving hydrolysis and acidogenesis of solid organic wastes. BIORESOURCE TECHNOLOGY 2009; 100:5594-9. [PMID: 19560914 DOI: 10.1016/j.biortech.2009.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Revised: 05/29/2009] [Accepted: 06/02/2009] [Indexed: 05/28/2023]
Abstract
The effects of porphyritic andesite on the hydrolysis and acidogenesis of solid organic wastes were investigated by batch and continuous experiments using a rotational drum fermentation system. The results of the batch experiment show that if porphyritic andesite (1%, 3%, and 5% reactants) is added initially, the pH level increases and hydrolysis and acidogenesis are accelerated. The highest surface based hydrolysis constant (26.4x10(-3) kgm(-2) d(-1)) and volatile solid degradation ratio (43.3%) were obtained at a 1% porphyritic andesite addition. In the continuous experiment, porphyritic andesite elevated the first order hydrolysis constant from 13.10x10(-3) d(-1) to 18.82x10(-3) d(-1). A particle mean diameter reduction rate of 33.05 microm/d and a volatile solid degradation rate of 3.53 g/L d(-1) were obtained under the hydraulic retention time of 4, 8, 12 and 16 d.
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Affiliation(s)
- Dawei Li
- Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, China Agricultural University, Qinghua Donglu 17, Beijing 100083, China
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Forbes C, O'Reilly C, McLaughlin L, Gilleran G, Tuohy M, Colleran E. Application of high rate, high temperature anaerobic digestion to fungal thermozyme hydrolysates from carbohydrate wastes. WATER RESEARCH 2009; 43:2531-2539. [PMID: 19371919 DOI: 10.1016/j.watres.2009.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 01/18/2009] [Accepted: 03/01/2009] [Indexed: 05/27/2023]
Abstract
The objective of this study was to examine the feasibility of using a two-step, fully biological and sustainable strategy for the treatment of carbohydrate rich wastes. The primary step in this strategy involves the application of thermostable enzymes produced by the thermophilic, aerobic fungus, Talaromyces emersonii, to carbohydrate wastes producing a liquid hydrolysate discharged at elevated temperatures. To assess the potential of thermophilic treatment of this hydrolysate, a comparative study of thermophilic and mesophilic digestion of four sugar rich thermozyme hydrolysate waste streams was conducted by operating two high rate upflow anaerobic hybrid reactors (UAHR) at 37 degrees C (R1) and 55 degrees C (R2). The operational performance of both reactors was monitored from start-up by assessing COD removal efficiencies, volatile fatty acid (VFA) discharge and % methane of the biogas produced. Rapid start-up of both R1 and R2 was achieved on an influent composed of the typical sugar components of the organic fraction of municipal solid waste (OFMSW). Both reactors were subsequently challenged in terms of volumetric loading rate (VLR) and it was found that a VLR of 9 gCOD l(-1)d(-1) at a hydraulic retention time (HRT) of 1 day severely affected the thermophilic reactor with instability characterised by a build up of volatile fatty acid (VFA) intermediates in the effluent. The influent to both reactors was changed to a simple glucose and sucrose-based influent supplied at a VLR of 4.5 gCOD l(-1)d(-1) and HRT of 2 days prior to the introduction of thermozyme hydrolysates. Four unique thermozyme hydrolysates were subsequently supplied to the reactors, each for a period of 10 HRTs. The applied hydrolysates were derived from apple pulp, bread, carob powder and cardboard, all of which were successfully and comparably converted by both reactors. The % total carbohydrate removal by both reactors was monitored during the application of the sugar rich thermozyme hydrolysates. This approach offers a sustainable technology for the treatment of carbohydrate rich wastes and highlights the potential of these wastes as substrates for the generation of second-generation biofuels.
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Affiliation(s)
- C Forbes
- Environmental Microbiology Research Unit, Department of Microbiology, National University of Ireland, Galway, Ireland.
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