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Lin M, Qiao W, Ren L, Sun Y, Zhang J, Dong R. Determination of effects of thermophilic and hyperthermophilic temperatures on anaerobic hydrolysis and acidogenesis of pig manure through a one-year study. BIORESOURCE TECHNOLOGY 2024; 391:129890. [PMID: 37858802 DOI: 10.1016/j.biortech.2023.129890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 10/01/2023] [Accepted: 10/16/2023] [Indexed: 10/21/2023]
Abstract
Improving hydrolysis and acidogenesis through thermophilic and hyperthermophilic temperatures is critical for enhancing the anaerobic decomposition of organic waste like pig manure. However, whether higher temperatures can provide more enhanced performance has not been elucidated experimentally. This study, therefore, conducted a 375-day continuous operation experiment at 55 and 70 °C with a 5-day hydraulic retention time. The two temperature reactors entered a stable state after about 200 days and long-term microbial acclimation markedly changed their performances. In the thermophilic and hyperthermophilic reactor, the hydrolysis efficiencies were obtained at 29.7 % and 27.3 % respectively, whereas the acidogenesis efficiency was relatively low at 1.0 % and 3.1 %. Due to the occurrence of methanogenesis, the volatile fatty acid concentration in the thermophilic reactor was only 45 % of that in the hyperthermophilic reactor. The thermophilic reactor exhibited higher bacterial diversity; however, this difference between the two reactors apparently did not correlate with hydrolysis and acidogenesis performance.
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Affiliation(s)
- Min Lin
- College of Engineering, China Agricultural University, Beijing 100083, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province 572025, China
| | - Wei Qiao
- College of Engineering, China Agricultural University, Beijing 100083, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province 572025, China.
| | - Lijuan Ren
- College of Engineering, China Agricultural University, Beijing 100083, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province 572025, China
| | - Yibo Sun
- College of Engineering, China Agricultural University, Beijing 100083, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province 572025, China
| | - Jiahao Zhang
- College of Engineering, China Agricultural University, Beijing 100083, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province 572025, China
| | - Renjie Dong
- College of Engineering, China Agricultural University, Beijing 100083, China
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2
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Ćwiertniewicz-Wojciechowska M, Cema G, Ziembińska-Buczyńska A. Sewage sludge pretreatment: current status and future prospects. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:88313-88330. [PMID: 37453013 PMCID: PMC10412499 DOI: 10.1007/s11356-023-28613-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 07/01/2023] [Indexed: 07/18/2023]
Abstract
Sewage sludge is regarded by wastewater treatment plants as problematic, from a financial and managerial point of view. Thus, a variety of disposal routes are used, but the most popular is methane fermentation. The proportion of macromolecular compounds in sewage sludges varies, and substrates treated in methane fermentation provide different amounts of biogas with various quality and quantity. Depending on the equipment and financial capabilities for methane fermentation, different methods of sewage sludge pretreatment are available. This review presents the challenges associated with the recalcitrant structure of sewage sludge and the presence of process inhibitors. We also examined the diverse methods of sewage sludge pretreatment that increase methane yield. Moreover, in the field of biological sewage sludge treatment, three future study propositions are proposed: improved pretreatment of sewage sludge using biological methods, assess the changes in microbial consortia caused with pretreatment methods, and verification of microbial impact on biomass degradation.
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Affiliation(s)
| | - Grzegorz Cema
- Department of Environmental Biotechnology, Silesian University of Technology, Akademicka 2A, 44-100, Gliwice, Poland
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3
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Zheng X, Chen X, Qu A, Yang W, Tao L, Li F, Huang J, Xu X, Tang J, Hou P, Han W. Valorisation of food waste for valuable by-products generation with economic assessment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 338:117762. [PMID: 37003224 DOI: 10.1016/j.jenvman.2023.117762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/02/2023] [Accepted: 03/17/2023] [Indexed: 06/19/2023]
Abstract
This study assessed the techno-economic feasibility of a biorefinery for valuable by-products (mainly hydrogen, ethanol and fertilizer) generation from food waste. The plant was designed to be built in Zhejiang province (China) with a processing capacity of 100 t food waste per day. It was found that the total capital investment (TCI) and annual operation cost (AOC) of the plant were US$ 7625549 and US$ 2432290.7 year-1, respectively. After the tax, US$ 3141867.6 year-1 of net profit could be reached. The payback period (PBP) was 3.5 years at a 7% discount rate. The internal rate of return (IRR) and return on investment (ROI) were 45.54% and 43.88%, respectively. Shutdown condition could happen with the feed of food waste less than 7.84 t day-1 (2587.2 t year-1) for the plant. This work was beneficial for attracting interests and even investment for valuable by-products generation from food waste in large scale.
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Affiliation(s)
- Xietian Zheng
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Xikai Chen
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Anlan Qu
- College of Horticulture, Northwest A&F University, Xi'an 712100, China
| | - Wenjing Yang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Lu Tao
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Feiyue Li
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Jingang Huang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China; School of Automation, The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, China
| | - Xiaobin Xu
- School of Automation, The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, China
| | - Junhong Tang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Pingzhi Hou
- School of Automation, The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, China
| | - Wei Han
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China; School of Automation, The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, China.
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4
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Wang L, Zhou J, Jia Q, Ma X, Zhao Y, Gong L, Zhang H. Anaerobic digestion of hydrothermally pretreated dewatered sewage sludge: effects of process conditions on methane production and the fate of phosphorus. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:66767-66780. [PMID: 37099108 DOI: 10.1007/s11356-023-26990-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 04/09/2023] [Indexed: 05/25/2023]
Abstract
The hydrothermal pretreatment (HTP) characteristics and the fate of phosphorus (P) and anaerobic digestion (AD) performance of dewatered sewage sludge (DSS) were investigated at different hydrothermal conditions. The maximum methane yield reached 241 mL CH4/g COD when the hydrothermal conditions were 200 °C-2 h-10% (A4), and the yield was 78.28% higher than that without pretreatment (A0) and 29.62% higher than that of the initial hydrothermal conditions (A1, 140 °C-1 h-5%). Proteins, polysaccharides, and volatile fatty acids (VFAs) were the main hydrothermal products of DSS. 3D-EEM analysis revealed that tyrosine, tryptophan proteins, and fulvic acids decreased after HTP, but the content of humic acid-like substances increased, and this phenomenon was more noticeable after AD. Solid-organic P was converted into liquid-P during the hydrothermal process, and nonapatite inorganic P was converted into organic P during AD. All samples achieved positive energy balance, and the energy balance of A4 was 10.50 kJ/g VS. Microbial analysis showed that the composition of the anaerobic microbial degradation community changed as the sludge organic composition was altered. Results showed that the HTP improved the anaerobic digestion of DSS.
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Affiliation(s)
- Luyu Wang
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Jun Zhou
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Qinwei Jia
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Xiaofan Ma
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Yuhang Zhao
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
| | - Lei Gong
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China.
| | - Haonan Zhang
- School of Environmental Engineering, Faculty of Environmental and Safety Engineering, Qingdao University of Science and Technology, 53, Zhengzhou Road, Qingdao, 266042, Shandong Province, China
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5
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Saravanan A, Senthil Kumar P, Rangasamy G, Hariharan R, Hemavathy RV, Deepika PD, Anand K, Karthika S. Strategies for enhancing the efficacy of anaerobic digestion of food industry wastewater: An insight into bioreactor types, challenges, and future scope. CHEMOSPHERE 2023; 310:136856. [PMID: 36243094 DOI: 10.1016/j.chemosphere.2022.136856] [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: 07/02/2022] [Revised: 09/28/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
Food waste have become a growing concern worldwide with raising population and economic growth. Wastewater discharged from food industries contains many valuable and toxic components that have a negative impact on the ecological system. Large amounts of wastewater are discharged from the food industry, which necessitates the creation of effective technologies. Wastewater from the food industry can be seen as a rich source of energy and a primary source for generating valuable products. Waste disposal and resource recovery are sustainably valued by anaerobic digestion of wastewater from the food sector. The characteristics, composition, and nature of wastewater produced from various food sectors are elaborated upon in this review. An overview of the anaerobic digestion process for wastewater treatment in the food industry is included. Enhancement strategies for the anaerobic digestion process have been discussed in detail. In addition, various types of reactors utilized for performing anaerobic digestion is illustrated. Though anaerobic digestion process possesses advantages, the challenges and future scope are examined for improving the outcome.
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Affiliation(s)
- A Saravanan
- Department of Sustainable Engineering, Institute of Biotechnology, Saveetha School of Engineering, SIMATS, Chennai, 602105, India
| | - P Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603110, India; Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603110, India; School of Engineering, Lebanese American University, Byblos, Lebanon.
| | - Gayathri Rangasamy
- University Centre for Research and Development & Department of Civil Engineering, Chandigarh University, Gharuan, Mohali, Punjab, 140413, India
| | - R Hariharan
- Department of Sustainable Engineering, Institute of Biotechnology, Saveetha School of Engineering, SIMATS, Chennai, 602105, India
| | - R V Hemavathy
- Department of Biotechnology, Rajalakshmi Engineering College, Chennai, 602105, India
| | - P D Deepika
- Department of Biotechnology, Rajalakshmi Engineering College, Chennai, 602105, India
| | - Krithika Anand
- Department of Biotechnology, Rajalakshmi Engineering College, Chennai, 602105, India
| | - S Karthika
- Department of Biotechnology, Rajalakshmi Engineering College, Chennai, 602105, India
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6
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Sillero L, Sganzerla WG, Carneiro TF, Solera R, Perez M. Techno-economic analysis of single-stage and temperature-phase anaerobic co-digestion of sewage sludge, wine vinasse, and poultry manure. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 325:116419. [PMID: 36257226 DOI: 10.1016/j.jenvman.2022.116419] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/19/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Anaerobic co-digestion (AcoD) is a mature and consolidated waste management technology that can transform agro-industrial by-products into biogas and digestate. This study conducted a techno-economic assessment of bioenergy and agricultural fertilizer production from AcoD of sewage sludge, wine vinasse, and poultry manure. In this case study, three configurations were investigated: i) Scenario 1, AcoD in thermophilic temperature; ii) Scenario 2, AcoD in mesophilic temperature; and iii) Scenario 3, AcoD in a temperature phase (TPAD) system, where the digestate produced in the first reactor (thermophilic) feeds the second reactor (mesophilic). The process was designed to manage 24,022 m³ wine vinasse y-1, 24,022 m³ sewage sludge y-1, and 480 m³ poultry manure y-1. The major cost was the fixed capital investment for the single-stage (320,981 USD) and TPAD processes (379,698 USD). The TPAD process produced the highest electricity (1058.99 MWh y-1) and heat (4765.47 GJ y-1) with the lowest cost of manufacturing for electricity (84.99 USD MWh-1), heat (0.019 USD MJ-1), and fertilizer (30.91 USD t-1). Regarding the profitability indicators, the highest net present value (509,011 USD) and the lowest payback time (4.24 y) were achieved for Scenario 3. In conclusion, TPAD is a profitable and sustainable waste-to-energy management technology that can be applied in a circular economy framework to recover bioenergy and fertilizer, contributing to decreasing the carbon footprint of the agri-food sector.
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Affiliation(s)
- Leonor Sillero
- Department of Environmental Technologies (IVAGRO), Faculty of Marine and Environmental Sciences (CASEM), University of Cádiz (UCA), Pol. Río San Pedro s/n, 11510, Puerto Real, Cádiz, Spain
| | - William Gustavo Sganzerla
- Department of Environmental Technologies (IVAGRO), Faculty of Marine and Environmental Sciences (CASEM), University of Cádiz (UCA), Pol. Río San Pedro s/n, 11510, Puerto Real, Cádiz, Spain; University of Campinas (UNICAMP), School of Food Engineering (FEA), Campinas, SP, Brazil
| | - Tania Forster Carneiro
- University of Campinas (UNICAMP), School of Food Engineering (FEA), Campinas, SP, Brazil
| | - Rosario Solera
- Department of Environmental Technologies (IVAGRO), Faculty of Marine and Environmental Sciences (CASEM), University of Cádiz (UCA), Pol. Río San Pedro s/n, 11510, Puerto Real, Cádiz, Spain.
| | - Montserrat Perez
- Department of Environmental Technologies (IVAGRO), Faculty of Marine and Environmental Sciences (CASEM), University of Cádiz (UCA), Pol. Río San Pedro s/n, 11510, Puerto Real, Cádiz, Spain
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7
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Optimization of Biogas Production from Sewage Sludge: Impact of Combination with Bovine Dung and Leachate from Municipal Organic Waste. SUSTAINABILITY 2022. [DOI: 10.3390/su14084380] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Biogas is a bioenergy produced from organic or all types of biological degradable wastes and could make it possible to limit energy dependence. Sludge is the best alternative substrate for biogas production at a community-level biogas plant. The literature shows that co-digestion can increase the efficiency of sludge anaerobic digestion. This research, thus, focused on (i) determining the conditions of optimal biogas production in the co-digestion of primary sludge (PS) and bovine dung (BD), (ii) evaluating the impact of leachate from organic waste and cellulose on biogas production. Primary sludge was collected in Bacau town wastewater treatment plant in Romania. The sampling of municipal solid waste was carried out in Ouagadougou pre-collect centers (Burkina Faso). Batch tests were conducted in glass bottles through anaerobic digestion (1 L). The following parameters were monitored during the digestion process: pH, volatile fatty acid (VFA), volatile solids (VS) and biogas production. Primary sludge, bovine dung and leachate showed 50.51%, 72.41% and 70.48% of volatile solids content, respectively. Sludge showed good stability, unlike the other two substrates, such as bovine dung and leachate, with VFA to alkalinity ratio 0.54. Leachate from organic waste had high values of VFA to alkalinity ratio > 3600. Co-digestion could make it possible to raise the levels of organic matter and improve microbial growth and the stability of anaerobic biomass. The best biogas production yield of 152.43 mL/g VS was obtained with a combination of 30% bovine dung and 70% primary sludge at 45 °C, with a 21.57% reduction in organic matter. An improvement in biogas productivity was effective with the addition of leachate, which could be used as an additive element during anaerobic digestion.
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Liu T, Miao P, Shi Y, Tang KHD, Yap PS. Recent advances, current issues and future prospects of bioenergy production: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 810:152181. [PMID: 34883167 DOI: 10.1016/j.scitotenv.2021.152181] [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: 10/11/2021] [Revised: 11/28/2021] [Accepted: 11/30/2021] [Indexed: 05/09/2023]
Abstract
With the immense potential of bioenergy to drive carbon neutrality and achieve the climate targets of the Paris Agreement, this paper aims to present the recent advances in bioenergy production as well as their limitations. The novelty of this review is that it covers a comprehensive range of strategies in bioenergy production and it provides the future prospects for improvement. This paper reviewed more than 200 peer-reviewed scholarly papers mainly published between 2010 and 2021. Bioenergy is derived from biomass, which, through thermochemical and biochemical processes, is converted into various forms of biofuels. This paper reveals that bioenergy production is temperature-dependent and thermochemical processes currently have the advantage of higher efficiency over biochemical processes in terms of lower response time and higher conversion. However, biochemical processes produce more volatile organic compounds and have lower energy and temperature requirements. The combination of the two processes could fill the shortcomings of a single process. The choices of feedstock are diverse as well. In the future, it can be anticipated that continuous technological development to enhance the commercial viability of different processes, as well as approaches of ensuring their sustainability, will be among the main aspects to be studied in greater detail.
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Affiliation(s)
- Tianqi Liu
- Department of Civil Engineering, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
| | - Pengyun Miao
- Department of Civil Engineering, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
| | - Yang Shi
- Department of Architecture and Design, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Kuok Ho Daniel Tang
- Environmental Science Program, Division of Science and Technology, Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai 519087, China
| | - Pow-Seng Yap
- Department of Civil Engineering, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China.
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Zhang X, Liu C, Chen Y, Zheng G, Chen Y. Source separation, transportation, pretreatment, and valorization of municipal solid waste: a critical review. ENVIRONMENT, DEVELOPMENT AND SUSTAINABILITY 2022; 24:11471-11513. [PMID: 34776765 PMCID: PMC8579419 DOI: 10.1007/s10668-021-01932-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 10/25/2021] [Indexed: 05/19/2023]
Abstract
Waste sorting is an effective means of enhancing resource or energy recovery from municipal solid waste (MSW). Waste sorting management system is not limited to source separation, but also involves at least three stages, i.e., collection and transportation (C&T), pretreatment, and resource utilization. This review focuses on the whole process of MSW management strategy based on the waste sorting perspective. Firstly, as the sources of MSW play an essential role in the means of subsequent valorization, the factors affecting the generation of MSW and its prediction methods are introduced. Secondly, a detailed comparison of approaches to source separation across countries is presented. Constructing a top-down management system and incentivizing or constraining residents' sorting behavior from the bottom up is believed to be a practical approach to promote source separation. Then, the current state of C&T techniques and its network optimization are reviewed, facilitated by artificial intelligence (AI) and the Internet of Things technologies. Furthermore, the advances in pretreatment strategies for enhanced sorting and resource recovery are introduced briefly. Finally, appropriate methods to valorize different MSW are proposed. It is worth noting that new technologies, such as AI, show high application potential in waste management. The sharing of (intermediate) products or energy of varying processing units will inject vitality into the waste management network and achieve sustainable development.
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Affiliation(s)
- Xuemeng Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092 People’s Republic of China
| | - Chao Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092 People’s Republic of China
| | - Yuexi Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092 People’s Republic of China
| | - Guanghong Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092 People’s Republic of China
| | - Yinguang Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092 People’s Republic of China
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10
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Accurate Estimation of Bicarbonate and Acetic Acid Concentrations with Wider Ranges in Anaerobic Media Using Classical FOS/TAC Titration Method. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app112411843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The determination of a volatile fatty acid content (FOS) and total alkalinity (TAC) can be carried out using Nordmann’s FOS/TAC titration method developed in the 1970s. This two-point titration (pH = 5 and 4.4) can be simply implemented and is widely employed by both the academic and industrial worlds. However, the present study proves that Nordmann’s method is only valid in limited ranges, since the titration of one FOS and TAC has an impact on the determination of the other, especially in extreme conditions. The present work develops a numerical tool with Scilab simulating the acid–base equilibria of titration. The program is efficient in predicting the experimental equivalent volumes obtained from Nordmann’s method with different combinations of sodium acetate and sodium bicarbonate contents. The mean absolute percentage errors (MAPE) between the simulation and experiment are below 7%. Two new formulas are developed, considering both equivalent volumes at pH = 5 and 4.4 to calibrate FOS and TAC values. The proposed formulas show their good performance in predicting various combinations of FOS and TAC contents in an anaerobic digestate at TAC ranging from 0 to 20,000 mg CaCO3·L−1 and FOS ranging from 0 to 31,000 mg HAc·L−1.
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11
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Ahmed B, Tyagi VK, Aboudi K, Naseem A, Álvarez-Gallego CJ, Fernández-Güelfo LA, Kazmi AA, Romero-García LI. Thermally enhanced solubilization and anaerobic digestion of organic fraction of municipal solid waste. CHEMOSPHERE 2021; 282:131136. [PMID: 34470172 DOI: 10.1016/j.chemosphere.2021.131136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/02/2021] [Accepted: 06/03/2021] [Indexed: 06/13/2023]
Abstract
Organic fraction of municipal solid waste (OFMSW) is an ideal substrate for biogas production; however, complex chemical structure and being heterogeneous obstruct its biotransformation in anaerobic digestion (AD) process. Thermal pre-treatment of OFMSW has been suggested to enhance the solubilization and improve the anaerobic digestibility of OFMSW. This paper critically and comprehensively reviews the characterization of OFMSW (physical, chemical, bromatological) and enlightens the valuable properties of OFMSW for waste valorization. In following sections, the advantages and limitations of AD of OFMSW are discussed, followed by the application of temperature phased AD, and various thermal pre-treatments, i.e., conventional thermal, microwave, and thermo-chemical for high rate bioenergy transformation. Effects of pre-treatment on COD, proteins, sugars and VS solubilization, and biogas yield are discussed. Formation of recalcitrant during thermal pre-treatment and the effect on anaerobic digestibility are considered. Full scale application, and techno-economic and environmental feasibility of thermal pre-treatment methods are also revealed. This review concluded that thermophilic (55 °C) and temperature phased anaerobic digestion, temperature phased anaerobic digestion, TPAD (55 + 37 °C) processes shows effective and stable performance at low HRTs and high OLRs and achieved higher methane yield than mesophilic digestion. The thermal pre-treatment at a lower temperature (120 °C) improves the net energy yield. However, high-temperature pre-treatment (>150 °C) result in decreased biogas yield and even lower than the non-pre-treated OFMSW, although a high degree of COD solubilization. The OFMSW solubilization in terms of COD, proteins, and sugars cannot accurately reflect thermal/hybrid pre-treatments' potential. Thus, substrate pre-treatment followed by anaerobic digestibility of pretreated substrate together can evaluate the actual effectiveness of thermal pre-treatment of OFMSW.
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Affiliation(s)
- Banafsha Ahmed
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, India
| | - Vinay Kumar Tyagi
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, India.
| | - Kaoutar Aboudi
- Department of Chemical Engineering and Food Technology, Institute of Vitivinicultural and Agri-food Research (IVAGRO), University of Cadiz, 11510, Puerto Real, Cadiz, Spain
| | - Azmat Naseem
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, India
| | - Carlos José Álvarez-Gallego
- Department of Chemical Engineering and Food Technology, Institute of Vitivinicultural and Agri-food Research (IVAGRO), University of Cadiz, 11510, Puerto Real, Cadiz, Spain
| | - Luis Alberto Fernández-Güelfo
- Department of Environmental Technologies, Faculty of Marine and Environmental Sciences, International Campus of Excellence (ceiA3), University of Cadiz, 11510, Puerto Real, Cadiz, Spain
| | - A A Kazmi
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, India
| | - Luis Isidoro Romero-García
- Department of Chemical Engineering and Food Technology, Institute of Vitivinicultural and Agri-food Research (IVAGRO), University of Cadiz, 11510, Puerto Real, Cadiz, Spain
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12
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Digested Sludge Quality in Mesophilic, Thermophilic and Temperature-Phased Anaerobic Digestion Systems. WATER 2021. [DOI: 10.3390/w13202839] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Anaerobic digestion (AD) technology is commonly used to treat sewage sludge from activated sludge systems, meanwhile alleviating the energy demand (and costs) for wastewater treatment. Most often, anaerobic digestion is run in single-stage systems under mesophilic conditions, as this temperature regime is considered to be more stable than the thermophilic one. However, it is known that thermophilic conditions are advantageous over mesophilic ones in terms of methane production and digestate hygienisation, while it is unclear which one is better concerning the digestate dewaterability. Temperature-phased anaerobic digestion (TPAD) is a double-stage AD process that combines the above-mentioned temperature regimes, by operating a thermophilic digester followed by a mesophilic one. The aim of this study is to compare the digestate quality of single-stage mesophilic and thermophilic AD and TPAD systems, in terms of the dewaterability, pathogenic safety and lower calorific value (LCV) and, based on the comparison, consider digested sludge final disposal alternatives. The research is conducted in lab-scale reactors treating waste-activated sludge. The dewaterability is tested by two methods, namely, centrifugation and mechanical pressing. The experimental results show that the TPAD system is the most beneficial in terms of organic matter degradation efficiency (32.4% against 27.2 for TAD and 26.0 for MAD), producing a digestate with a high dewaterability (8.1–9.8% worse than for TAD and 6.2–12.0% better than for MAD) and pathogenic safety (coliforms and Escherichia coli were not detected, and Clostridium perfringens were counted up to 4.8–4.9 × 103, when for TAD it was only 1.4–2.5 × 103, and for MAD it was 1.3–1.8 × 104), with the lowest LCV (19.2% against 15.4% and 15.8% under thermophilic and mesophilic conditions, respectively). Regarding the final disposal, the digested sludge after TAD can be applied directly in agriculture; after TPAD, it can be used as a fertilizer only in the case where the fermenter HRT assures the pathogenic safety. The MAD digestate is the best for being used as a fuel preserving a higher portion of organic matter, not transforming into biogas during AD.
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