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Yin Y, Qi X, Gao L, Lu X, Yang X, Xiao K, Liu Y, Qiu Y, Huang X, Liang P. Quantifying Methane Influx from Sewer into Wastewater Treatment Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:9582-9590. [PMID: 38780619 DOI: 10.1021/acs.est.4c00820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Wastewater treatment contributes substantially to methane (CH4) emissions, yet monitoring and tracing face challenges because the treatment processes are often treated as a "black box". Particularly, despite growing interest, the amount of CH4 carryover and influx from the sewer and its impacts on overall emissions remain unclear. This study quantified CH4 emissions from six wastewater treatment plants (WWTPs) across China, utilizing existing multizonal odor control systems, with a focus on Beijing and Guiyang WWTPs. In the Beijing WWTP, almost 90% of CH4 emissions from the wastewater treatment process were conveyed through sewer pipes, affecting emissions even in the aerobic zone of biological treatment. In the Guiyang WWTP, where most CH4 from the sewer was released at the inlet well, a 24 h online monitoring revealed CH4 fluctuations linked to neighborhood water consumption and a strong correlation to influent COD inputs. CH4 emission factors monitored in six WWTPs range from 1.5 to 13.4 gCH4/kgCODrem, higher than those observed in previous studies using A2O technology. This underscores the importance of considering CH4 influx from sewer systems to avoid underestimation. The odor control system in WWTPs demonstrates its potential as a cost-effective approach for tracing, monitoring, and mitigating CH4.
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Affiliation(s)
- Yijun Yin
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Xiang Qi
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Lan Gao
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Xi Lu
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Xufei Yang
- Department of Agricultural and Biosystems Engineering, South Dakota State University, Brookings, South Dakota 57007, United States
| | - Kang Xiao
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yanchen Liu
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Yong Qiu
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Xia Huang
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Peng Liang
- School of Environment, Tsinghua University, Beijing 100084, P. R. China
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2
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Wang J, Zhang N, Xu S, Shao Z, Jiang C, Yuan H, Wang C, Zheng X, Chi Y, Zhang W, Wang D, Zhuang X. Carbon footprint analysis and comprehensive evaluation of municipal wastewater treatment plants under different typical upgrading and reconstruction modes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 880:163335. [PMID: 37030360 DOI: 10.1016/j.scitotenv.2023.163335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 03/11/2023] [Accepted: 04/03/2023] [Indexed: 04/15/2023]
Abstract
The issue of greenhouse gas (GHG) emissions resulting from the upgrading and reconstruction of municipal wastewater treatment plants (MWWTPs) along with improved water quality is receiving attention and research. There is an urgent need to explore the impact of upgrading and reconstruction on carbon footprint (CF) in order to address concerns that the upgrading and reconstruction will increase GHG emissions while improving water quality. Here we accounted for the CF of five MWWTPs in Zhejiang Province, China, before and after three different upgrading and reconstruction models - "Improving quality and efficiency" ("Mode I"), "Upgrading and renovation" ("Mode U") and "Improving quality and efficiency plus Upgrading and renovation" ("Mode I plus U"). The upgrading and reconstruction was found to not necessarily result in more GHG emissions. In contrast, the "Mode I" had a more significant advantage in terms of CF reduction (1.82-12.6 % reduction in CF). Overall, the ratio of indirect emissions to direct emissions (indirect emissions/direct emissions) and the amount of GHG emitted per unit of pollutant removed (CFCOD、CFTN、CFTP) decreased, while both the carbon and energy neutral rates increased significantly (up to 33.29 % and 79.36 % respectively) after all three upgrading and reconstruction modes. In addition, the wastewater treatment efficiency and capacity are the main factors that affect the level of carbon emission. The results of this study can provide a calculation model that can be used for other similar MWWTPs during the upgrading and reconstruction processes. More importantly, it can provide a new research perspective as well as valuable information to revisit the impact of upgrading and reconstruction in MWWTPs on GHG emissions.
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Affiliation(s)
- Jinglin Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China; Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu 322000, Zhejiang, China
| | - Nan Zhang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Shengjun Xu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Zhiping Shao
- Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu 322000, Zhejiang, China
| | - Cancan Jiang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Hongying Yuan
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Cong Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xiaoxu Zheng
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yongzhi Chi
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Weijun Zhang
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China
| | - Dongsheng Wang
- Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu 322000, Zhejiang, China
| | - Xuliang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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3
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Song C, Zhu JJ, Willis JL, Moore DP, Zondlo MA, Ren ZJ. Methane Emissions from Municipal Wastewater Collection and Treatment Systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:2248-2261. [PMID: 36735881 PMCID: PMC10041530 DOI: 10.1021/acs.est.2c04388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Municipal wastewater collection and treatment systems are critical infrastructures, and they are also identified as major sources of anthropogenic CH4 emissions that contribute to climate change. The actual CH4 emissions at the plant- or regional level vary greatly due to site-specific conditions as well as high seasonal and diurnal variations. Here, we conducted the first quantitative analysis of CH4 emissions from different types of sewers and water resource recovery facilities (WRRFs). We examined variations in CH4 emissions associated with methods applied in different monitoring campaigns, and identified main CH4 sources and sinks to facilitate carbon emission reduction efforts in the wastewater sector. We found plant-wide CH4 emissions vary by orders of magnitude, from 0.01 to 110 g CH4/m3 with high emissions associated with plants equipped with anaerobic digestion or stabilization ponds. Rising mains show higher dissolved CH4 concentrations than gravity sewers when transporting similar raw sewage under similar environmental conditions, but the latter dominates most collection systems around the world. Using the updated data sets, we estimated annual CH4 emission from the U.S. centralized, municipal wastewater treatment to be approximately 10.9 ± 7.0 MMT CO2-eq/year, which is about twice as the IPCC (2019) Tier 2 estimates (4.3-6.1 MMT CO2-eq/year). Given CH4 emission control will play a crucial role in achieving net zero carbon goals by the midcentury, more studies are needed to profile and mitigate CH4 emissions from the wastewater sector.
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Affiliation(s)
- Cuihong Song
- Department
of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey08544United States
| | - Jun-Jie Zhu
- Department
of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey08544United States
- Andlinger
Center for Energy and the Environment, Princeton
University, Princeton, New Jersey08544, United States
| | - John L. Willis
- Brown
and Caldwell, Atlanta, Georgia30328, United States
| | - Daniel P. Moore
- Department
of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey08544United States
| | - Mark A. Zondlo
- Department
of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey08544United States
| | - Zhiyong Jason Ren
- Department
of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey08544United States
- Andlinger
Center for Energy and the Environment, Princeton
University, Princeton, New Jersey08544, United States
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Su Q, Dai H, Xie S, Yu X, Lin Y, Singh VP, Karthikeyan R. Water-Energy-Carbon Nexus: Greenhouse Gas Emissions from Integrated Urban Drainage Systems in China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:2093-2104. [PMID: 36696288 DOI: 10.1021/acs.est.2c08583] [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] [Indexed: 06/17/2023]
Abstract
Greenhouse gas (GHG) emissions from integrated urban drainage systems (IUDSs), including sewer, wastewater treatment plants (WWTPs), and receiving water systems, have not yet been integrated due to the lack of modeling tools. Here, we updated the computable general equilibrium-based System Dynamics and Water Environmental Model (CGE-SyDWEM), a recently developed model simulating the water-energy-carbon nexus at the watershed level, to calculate the direct and indirect (electricity use and external) GHG emissions from IUDSs considering carbon mitigation strategies and water engineering practices. The updated CGE-SyDWEM was applied to an estuary watershed in Shenzhen, the fourth largest city in China. With increasing socio-economic development and water infrastructure systems upgrading, GHG emissions are projected to increase from 129.2 (95% CI: 95.9-162.5) kt in 2007 to 190.7 (144.8-236.6) kt in 2025, with 89% from WWTPs (direct: 17%; electricity use: 65%; and external: 7%), 10% from the sewer (direct: 1% and electricity use: 9%) and 1% from receiving waters (direct). Carbon mitigation can reduce GHG emissions by 7% and emission intensity by 6% by 2025, with 63% contributed by external emission reduction from chemical uses. The integrated model can aid water, energy, and carbon decision-makers in finding cost-effective solutions for water and energy security in the future.
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Affiliation(s)
- Qiong Su
- Department of Agricultural Sciences, Clemson University, Clemson, South Carolina29634, United States
| | - Hancheng Dai
- College of Environmental Sciences and Engineering, Peking University, Beijing100871, China
- Institute for Global Health and Development, Peking University, Beijing100871, China
| | - Shuyan Xie
- China National Environmental Monitoring Center, Beijing100012, China
| | - Xiangying Yu
- Guangdong Provincial Academy of Environmental Science, Guangzhou510045, China
| | - Yun Lin
- Joint Institute for Regional Earth System Science and Engineering and Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, California90095, United States
| | - Vijay P Singh
- Department of Biological and Agricultural Engineering & Zachry Department of Civil & Environmental Engineering, Texas A&M University, College Station, Texas77843, United States
- National Water and Energy Center, UAE University, Al Ain15551, UAE
| | - Raghupathy Karthikeyan
- Department of Agricultural Sciences, Clemson University, Clemson, South Carolina29634, United States
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5
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Nowrouzi M, Abyar H, Rohani S. A comparison of nitrogen removal systems through cost-coupled life cycle assessment and energy efficiency analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159787. [PMID: 36309255 DOI: 10.1016/j.scitotenv.2022.159787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/15/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
The global water crisis reflects the necessity of exploring the best approaches for the water supply. Therefore, for the first time, the current study compares nitrogen removal systems (NRSs) from life cycle assessment (LCA), economic, kinetic, thermodynamic, and synergistic perspectives. The assessed systems were sequential batch reactor (SBR), oxic/anoxic (OA), and oxic/anaerobic/oxic (OAO) bioreactors. Among all, the SBR configuration showed the best efficiency (98.74 %) for nitrogen removal. The environmental impacts notably presented by marine + freshwater ecotoxicity (53.76 %), and climate change categories (16.39 %), significantly because of metal emissions. Non-renewable sources supplied 95 % of total energy demand. The operation of NRSs showed the most impact on human health (63.67 %) through CH4 and CO2 emissions. The total costs significantly belonged to the construction (<86.37 %) > amortization> operation. The influent COD illustrated the most role in environmental burdens (16.44 %) based on the sensitivity analysis. The removal reaction was endothermic, physical, non-spontaneous, and followed a pseudo-second-order kinetic model (R2 > 0.98). The chemical exergy provided the major portion of the total calculated exergy (83 %). The exergetic efficiency of the system was 69 %, which was predominantly supplied by biogas (∼50.75 %). Accordingly, this study can present a stepwise guideline for further related investigations.
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Affiliation(s)
- Mohsen Nowrouzi
- Department of Science and Biotechnology, Faculty of Nano and Bio Science and Technology, Persian Gulf University, Bushehr 75169-13798, Iran.
| | - Hajar Abyar
- Department of Environmental Sciences, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan 49189-43464, Iran.
| | - Sohrab Rohani
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario N6A 5B9, Canada
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6
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Contreras JA, Valenzuela EI, Quijano G. Nitrate/nitrite-dependent anaerobic oxidation of methane (N-AOM) as a technology platform for greenhouse gas abatement in wastewater treatment plants: State-of-the-art and challenges. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115671. [PMID: 35816965 DOI: 10.1016/j.jenvman.2022.115671] [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: 04/15/2022] [Revised: 06/21/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
Nitrate/nitrite-dependent anaerobic oxidation of methane (N-AOM) is a metabolic process recently discovered and partially characterized in terms of the microorganisms and pathways involved. The N-AOM process can be a powerful tool for mitigating the impacts of greenhouse gas emissions from wastewater treatment plants by coupling the reduction of nitrate or nitrite with the oxidation of residual dissolved methane. Besides specific anaerobic methanotrophs such as bacteria members of the phylum NC10 and archaea belonging to the lineage ANME-2d, recent reports suggested that other methane-oxidizing bacteria in syntrophy with denitrifiers can also perform the N-AOM process, which facilitates the application of this metabolic process for the oxidation of residual methane under realistic scenarios. This work constitutes a state-of-art review that includes the fundamentals of the N-AOM process, new information on process microbiology, bioreactor configurations, and operating conditions for process implementation in WWTP. Potential advantages of the N-AOM process over aerobic methanotrophic biotechnologies are presented, including the potential interrelation of the N-AOM with other nitrogen removal processes within the WWTP, such as the anaerobic ammonium oxidation. This work also addressed the challenges of this biotechnology towards its application at full scale, identifying and discussing critical research niches.
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Affiliation(s)
- José A Contreras
- Laboratory for Research on Advanced Processes for Water Treatment, Instituto de Ingeniería, Unidad Académica Juriquilla, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro, 76230, Mexico
| | - Edgardo I Valenzuela
- Laboratory for Research on Advanced Processes for Water Treatment, Instituto de Ingeniería, Unidad Académica Juriquilla, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro, 76230, Mexico
| | - Guillermo Quijano
- Laboratory for Research on Advanced Processes for Water Treatment, Instituto de Ingeniería, Unidad Académica Juriquilla, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro, 76230, Mexico.
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7
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Marami H, Tsapekos P, Khoshnevisan B, Madsen JA, Andersen JK, Rafiee S, Angelidaki I. Going beyond conventional wastewater treatment plants within circular bioeconomy concept - a sustainability assessment study. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 85:1878-1903. [PMID: 35358077 DOI: 10.2166/wst.2022.096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Wastewater treatment plants (WWTP) have extensive energy processes that undermine their economic and environmental performance. In this context, the integration of wastewater treatment with other biochemical processes such as co-digestion of sludge with organic wastes, and production of value-added products at their downstream processes will shift conventional WWTPs into biorefinery platforms with better sustainability performance. The sustainability of such a biorefinery platform has been investigated herein using an economic and life cycle assessment approach. This WWTP-based biorefinery treats wastewater from Copenhagen municipality, co-digests the source-sorted organic fraction of municipal solid waste and sludge, and upgrades biogas into biomethane using a hydrogen-assisted upgrading method. Apart from bioenergy, this biorefinery also produces microbial protein (MP) using recovered nutrients from WWTP's reject water. The net environmental savings achieved in two damage categories, i.e., -1.07 × 10-2 species.yr/FU in ecosystem quality and -1.68 × 106 USD/FU in resource scarcity damage categories along with high potential windows for the further environmental profile improvements make this biorefinery platform so encouraging. Despite being promising in terms of environmental performance, the high capital expenditure and low gross profit have undermined the economic performance of the proposed biorefinery. Technological improvements, process optimization, and encouraging incentives/subsidies are still needed to make this platform economically feasible.
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Affiliation(s)
- Hadis Marami
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Tehran, Iran
| | - Panagiotis Tsapekos
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Kgs Lyngby DK-2800, Denmark
| | - Benyamin Khoshnevisan
- Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Odense, Denmark
| | | | | | - Shahin Rafiee
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Tehran, Iran
| | - Irini Angelidaki
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Kgs Lyngby DK-2800, Denmark
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Hua H, Jiang S, Yuan Z, Liu X, Zhang Y, Cai Z. Advancing greenhouse gas emission factors for municipal wastewater treatment plants in China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 295:118648. [PMID: 34890748 DOI: 10.1016/j.envpol.2021.118648] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 10/09/2021] [Accepted: 12/05/2021] [Indexed: 06/13/2023]
Abstract
Estimations of greenhouse gas (GHG) emissions from municipal wastewater treatment plants (MWTPs) remain significant uncertainties in China owing to a lack of reliable emission factors (EFs). This study developed a framework to obtain multi-level (technology, province, and nation) GHG EFs of MWTPs using a database containing 3107 MWTPs in China and published site-specific monitoring data. Results show that GHG EFs of different technologies range widely from 180.0 to 615.7 g CO2-eq/t wastewater, and significant differences are also observed among different provinces in China (190.5-600.3 g CO2-eq/t wastewater), which are generally lower than the previous estimates. It confirms the importance of more detailed technology classification and considering the technological disparity of different provinces in refining GHG estimations of MWTPs. To test the feasibility of the developed EFs, we compared GHG emissions from MWTPs based on multi-level EFs at different spatial and temporal scales. Similar estimation results imply that selecting corresponding EF depending on the availability of activity data would simplify GHG estimations of MWTPs without sacrificing much accuracy. This study contributes a set of well-developed EFs to improve the estimates of GHG emissions from MWTPs, and also offers a method to develop GHG EFs for other sectors.
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Affiliation(s)
- Hui Hua
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Songyan Jiang
- School of Management Science and Engineering, Nanjing University of Information Science and Technology, Nanjing, 210044, PR China
| | - Zengwei Yuan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
| | - Xuewei Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - You Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Zican Cai
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
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9
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Rong C, Luo Z, Wang T, Guo Y, Kong Z, Wu J, Ji J, Qin Y, Hanaoka T, Sakemi S, Ito M, Kobayashi S, Kobayashi M, Li YY. Chemical oxygen demand and nitrogen transformation in a large pilot-scale plant with a combined submerged anaerobic membrane bioreactor and one-stage partial nitritation-anammox for treating mainstream wastewater at 25 °C. BIORESOURCE TECHNOLOGY 2021; 341:125840. [PMID: 34469821 DOI: 10.1016/j.biortech.2021.125840] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/19/2021] [Accepted: 08/21/2021] [Indexed: 06/13/2023]
Abstract
A novel municipal wastewater treatment process towards energy neutrality and reduced carbon emissions was established by combining a submerged anaerobic membrane bioreactor (SAnMBR) with a one-stage partial nitritation-anammox (PN/A), and was demonstrated at pilot-scale at 25 °C. The overall COD and BOD5 removal efficiencies were 95.1% and 96.4%, respectively, with 20.3 mg L-1 COD and 5.2 mg L-1 BOD5 remaining in the final effluent. The total nitrogen (TN) removal efficiency was 81.7%, resulting 7.3 mg L-1 TN was discharged from the system. The biogas yield was 0.222 NL g-1 COD removed with a methane content range of 78-81%. Approximately 90% of influent COD was removed in the SAnMBR, and 70% of influent nitrogen was removed in the PN/A. The denitrification which occurred in the PN/A enhanced overall COD and nitrogen removal. The successful operation of this pilot-scale plant indicates the SAnMBR-PN/A process is suitable for treating real municipal wastewater.
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Affiliation(s)
- Chao Rong
- Graduate School of Environmental Studies, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Zibin Luo
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Tianjie Wang
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Yan Guo
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Zhe Kong
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Jiang Wu
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan; Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies, Tsukuba 305-8506, Japan
| | - Jiayuan Ji
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Yu Qin
- Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Taira Hanaoka
- Solution Engineering Group, Environmental Engineering Department, Mitsubishi Kakoki Kaisha, Ltd., 1-2 Miyamae-Cho, Kawasaki-Ku, Kawasaki, Kanagawa 210-0012, Japan
| | - Shinichi Sakemi
- Solution Engineering Group, Environmental Engineering Department, Mitsubishi Kakoki Kaisha, Ltd., 1-2 Miyamae-Cho, Kawasaki-Ku, Kawasaki, Kanagawa 210-0012, Japan
| | - Masami Ito
- Global Water Recycling and Reuse System Association, Japan, 5-1, Soto-Kanda 1-Chome, Chiyoda-Ku, Tokyo 101-0021, Japan
| | - Shigeki Kobayashi
- Global Water Recycling and Reuse System Association, Japan, 5-1, Soto-Kanda 1-Chome, Chiyoda-Ku, Tokyo 101-0021, Japan
| | - Masumi Kobayashi
- Separation and Aqua Chemicals Department, Mitsubishi Chemical Corporation, Gate City Osaki East Tower, 11-2 Osaki 1-chome, Shinagawa-Ku, Tokyo 141-0032, Japan
| | - Yu-You Li
- Graduate School of Environmental Studies, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan; Laboratory of Environmental Protection Engineering, Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba Ward, Sendai, Miyagi 980-8579, Japan.
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10
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Baeten JE, Walgraeve C, Granja RC, van Loosdrecht MCM, Volcke EIP. Unaerated feeding alters the fate of dissolved methane during aerobic wastewater treatment. WATER RESEARCH 2021; 204:117619. [PMID: 34509867 DOI: 10.1016/j.watres.2021.117619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 08/10/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
In municipal wastewater treatment plants, some dissolved methane can enter the aerobic bioreactors. This greenhouse gas originates from sewers and return flows from anaerobic sludge treatment. In well-mixed conventional activated sludge reactors, methane emissions are largely avoided because methane oxidizing bacteria consume a large fraction, even without optimizing for this purpose. In this work, the fate of dissolved methane is studied in aerobic granular sludge reactors, as they become increasingly popular. The influence of the characteristic design and operating conditions of these reactors are studied with a mathematical model with apparent conversion kinetics and stripping: the separation of feeding and aeration in time, a higher substrate transport resistance, a high retention time of granular biomass and a taller water column. Even for a best-case scenario combining an unrealistically low intragranule substrate transport resistance, a high retention time, a tall reactor, an extremely high influent methane concentration and no oxygen limitation, the methane conversion efficiency was only 12% when feeding and aeration were separated in time, which is lower than for continuous activated sludge reactors under typical conditions. A more rigorous model was used to confirm the limited conversion, considering the multi-species and multi-substrate biofilm kinetics, anoxic methane consumers and the high substrate concentration at the bottom during upward plug flow feeding. The observed limited methane conversion is mainly due to the high concentration that accumulates during unaerated feeding phases, which favours stripping more than conversion in the subsequent aeration phase. Based on these findings, strategies were proposed to mitigate methane emissions from wastewater treatment plants with sequentially operated reactors.
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Affiliation(s)
- Janis E Baeten
- Department of Green chemistry and Technology, Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Christophe Walgraeve
- Department of Green chemistry and Technology, Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Rafael Cesar Granja
- Department of Green chemistry and Technology, Ghent University, Coupure Links 653, Ghent 9000, Belgium
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, the Netherlands
| | - Eveline I P Volcke
- Department of Green chemistry and Technology, Ghent University, Coupure Links 653, Ghent 9000, Belgium.
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11
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Baeten JE, van Dijk EJH, Pronk M, van Loosdrecht MCM, Volcke EIP. Potential of off-gas analyses for sequentially operated reactors demonstrated on full-scale aerobic granular sludge technology. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 787:147651. [PMID: 34000528 DOI: 10.1016/j.scitotenv.2021.147651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/22/2021] [Accepted: 05/05/2021] [Indexed: 06/12/2023]
Abstract
This work shows how more variables can be monitored with a single off-gas sampler on sequentially operated than on continuously fed and aerated reactors and applies the methods to data from a full-scale aerobic granular sludge reactor as a demonstration and to obtain insight in this technology. First, liquid-gas transfer rates were calculated. Oxygen (O2) absorption and carbon dioxide (CO2) emission rates showed comparable cyclic trends due to the coupling of O2 consumption and CO2 production. Methane (CH4) emissions showed a stripping profile and nitrous oxide (N2O) emissions showed two peaks each cycle, which were attributed to different production pathways. Secondly, aeration characteristics were calculated, of which the gradual improvement within cycles was explained by surfactants degradation. Thirdly, liquid phase concentrations were estimated from off-gas measurements via a novel calculation procedure. As such, an average influent CH4 concentration of 0.7 g·m-3 was found. Fourthly, reaction rates could be estimated from off-gas data because no feeding or discharge occurred during reaction phases. The O2 consumption rate increased with increasing dissolved oxygen and decreased once nitrification was complete. Fifthly, greenhouse gas emissions could be derived, indicating a 0.06% N2O emission factor. Sixthly, off-gas gave an indication of influent characteristics. The CO2 emitted per kg COD catabolized corresponded with the TOC/COD ratio of typical wastewater organics in cycles with balanced nitrification and denitrification. High nitrogen removal efficiencies were associated with high catabolized COD/N ratios as estimated from the O2 absorption. Finally, mass balances could be closed using off-gas O2 data. As such, an observed yield of 0.27 g COD/g COD was found. All these variables could be estimated with a single sampler because aeration without feeding creates a more homogeneous off-gas composition and simplifies liquid-phase mass balances. Therefore, off-gas analyzers may have a broader application potential for sequentially operated reactors than currently acknowledged.
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Affiliation(s)
- Janis E Baeten
- BioCo Research Group, Department of Green Chemistry and Technology, Coupure Links 653, 9000 Gent, Ghent University, Belgium.
| | - Edward J H van Dijk
- Environmental Biotechnology, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands; Royal HaskoningDHV, Laan 1914 35, Amersfoort 3800, AL, the Netherlands.
| | - Mario Pronk
- Environmental Biotechnology, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands; Royal HaskoningDHV, Laan 1914 35, Amersfoort 3800, AL, the Netherlands.
| | - Mark C M van Loosdrecht
- Environmental Biotechnology, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands.
| | - Eveline I P Volcke
- BioCo Research Group, Department of Green Chemistry and Technology, Coupure Links 653, 9000 Gent, Ghent University, Belgium.
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12
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Li Y, Xu Y, Fu Z, Li W, Zheng L, Li M. Assessment of energy use and environmental impacts of wastewater treatment plants in the entire life cycle: A system meta-analysis. ENVIRONMENTAL RESEARCH 2021; 198:110458. [PMID: 33188763 DOI: 10.1016/j.envres.2020.110458] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 08/27/2020] [Accepted: 11/06/2020] [Indexed: 06/11/2023]
Abstract
Wastewater treatment plants (WWTPs) play a critical role in the sustainable development of water resources due to its outstanding ability of removing pollutants from complex influent wastewater and generating clean and safe effluent. This paper innovatively adopted the meta-analysis method in view of published LCA studies to assess the energy use and environmental impacts of WWTPs during their life cycle. The search and screening process determined a useful data source with 54 LCA literatures covering 109 relevant case studies. The meta-analysis results revealed that, compared with other regions, the WWTPs in China have the higher intensity in terms of energy use, global warming potential (GWP), eutrophication potential (EP), acidification potential (AP), photochemical oxidation (PHO), freshwater ecotoxicity potential (FETP) and terrestrial ecotoxicity potential (TETP) categories, implying that the energy conservation and emission reduction strategies are necessary to wastewater treatment industry in China. Moreover, compared with A/A/O and CASS processes, the A/O process consumes less energy and results in lower GWP and AP intensity, but affects adversely the natural water-body protection due to undesirable treatment efficiency. Furthermore, the treatment capacities of medium and large scales (i.e. 5-20 × 104 m3/d) are most reasonable sizes for WWTPs since their intensity of energy use, GWP, EP and AP are under a relatively low level. Finally, a strict effluent discharge standard is highly recommended from the perspective of protecting aquatic environment, although it leads to a higher energy consumption. The findings of this study could provide valuable references for promoting healthy and sustainable wastewater treatment industry.
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Affiliation(s)
- Ye Li
- MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Ye Xu
- MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Zhenghui Fu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Wei Li
- MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
| | - Lijun Zheng
- School of Materials and Metallurgy, University of Science and Technology Liaoning, Anshan, 114051, China.
| | - Mengran Li
- MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
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Onodera T, Komatsu K, Kohzu A, Kanaya G, Mizuochi M, Syutsubo K. Differences in the isotopic signature of activated sludge in four types of advanced treatment processes at a municipal wastewater treatment plant. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 286:112264. [PMID: 33684800 DOI: 10.1016/j.jenvman.2021.112264] [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: 12/14/2020] [Revised: 02/04/2021] [Accepted: 02/21/2021] [Indexed: 06/12/2023]
Abstract
The natural abundance of stable isotopes is a powerful tool for evaluating biological reactions and process conditions. However, there are few stable isotope studies on the wastewater treatment process. This study carried out the first investigation on variations in natural abundance of carbon and nitrogen stable isotope ratios (δ13C and δ15N) of activated sludge in four types of advanced treatment process (extended aeration activated sludge (EAAS), aerobic-anoxic-aerobic (A2O), recycled nitrification-denitrification (RND), and modified Bardenpho (MB)) at a municipal wastewater treatment plant. The δ13C and δ15N values of influent suspended solids settled in the primary sedimentation tank (i.e., primary sludge) ranged from -25.4‰ to -24.6‰ and 0.5‰-2.9‰, respectively, during monitoring periods. The δ13C values of the activated sludge were -24.6‰ to -23.6‰ (EAAS), -25.4‰ to -24.3‰ (A2O), -25.7‰ to -24.9‰ (RND), and -25.7‰ to -24.3‰ (MB). The δ13C values of the activated sludge were similar to those of influent suspended solids. However, the δ13C values of activated sludge in EAAS was significantly higher than in A2O, RND, and MB. Meanwhile, the δ15N values of activated sludge were obviously higher than influent suspended solids; 5.8‰-7.5‰ (EAAS), 6.6‰-8.1‰ (A2O), 5.5‰-7.5‰ (RND), and 5.3‰-7.6‰ (MB). Changes in δ13C and δ15N values of the activated sludge within the treatment system were also found. These findings indicate that changes in δ13C and δ15N values of the activated sludge rely on important function for biological wastewater treatment such as nitrification, denitrification, and methane oxidation through wastewater treatment over time.
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Affiliation(s)
- Takashi Onodera
- Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Kazuhiro Komatsu
- Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Ayato Kohzu
- Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Gen Kanaya
- Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Motoyuki Mizuochi
- Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Kazuaki Syutsubo
- Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
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14
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Jaromin-Gleń K, Babko R, Kuzmina T, Danko Y, Łagód G, Polakowski C, Szulżyk-Cieplak J, Bieganowski A. Contribution of prokaryotes and eukaryotes to CO 2 emissions in the wastewater treatment process. PeerJ 2020; 8:e9325. [PMID: 32596047 PMCID: PMC7305776 DOI: 10.7717/peerj.9325] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 05/18/2020] [Indexed: 11/23/2022] Open
Abstract
Reduction of the greenhouse effect is primarily associated with the reduction of greenhouse gas (GHG) emissions. Carbon dioxide (CO2) is one of the gases that increases the greenhouse effect - it is responsible for about half of the greenhouse effect. Significant sources of CO2 are wastewater treatment plants (WWTPs) and waste management, with about 3% contribution to global emissions. CO2 is produced mainly in the aerobic stage of wastewater purification and is a consequence of activated sludge activity. Although the roles of activated sludge components in the purification process have been studied quite well, their quantitative contribution to CO2 emissions is still unknown. The emission of CO2 caused by prokaryotes and eukaryotes over the course of a year (taking into account subsequent seasons) in model sequencing batch reactors (SBR) is presented in this study. In this work, for the first time, we aimed to quantify this contribution of eukaryotic organisms to total CO2 emissions during the WWTP process. It is of the order of several or more ppm. The contribution of CO2 produced by different components of activated sludge in WWTPs can improve estimation of the emissions of GHGs in this area of human activity.
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Affiliation(s)
| | - Roman Babko
- Schmalhausen Institute of Zoology, National Academy of Sciences, Kiev, Ukraine
| | | | - Yaroslav Danko
- Sumy Makarenko State Pedagogical University, Sumy, Ukraine
| | - Grzegorz Łagód
- Environmental Engineering Faculty, Lublin University of Technology, Lublin, Poland
| | - Cezary Polakowski
- Institute of Agrophysics, Polish Academy of Sciences, Lublin, Poland
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15
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Han Y, Sun Y, Chen H, Guo X, Yu C, Li Y, Liu J, Xiao B. Effects of wastewater treatment processes on the sludge reduction system with 2,4-dichlorophenol: Sequencing batch reactor and anaerobic-anoxic-oxic process. J Biotechnol 2017; 251:99-105. [DOI: 10.1016/j.jbiotec.2017.04.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/17/2017] [Accepted: 04/23/2017] [Indexed: 10/19/2022]
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16
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Hu Z, Ma R. Distribution and characteristic of nitrite-dependent anaerobic methane oxidation bacteria by comparative analysis of wastewater treatment plants and agriculture fields in northern China. PeerJ 2016; 4:e2766. [PMID: 27994974 PMCID: PMC5160924 DOI: 10.7717/peerj.2766] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 11/07/2016] [Indexed: 11/20/2022] Open
Abstract
Nitrite-dependent anaerobic methane oxidation (n-damo) is a recently discovered biological process which has been arousing global attention because of its potential in minimizing greenhouse gases emissions. In this study, molecular biological techniques and potential n-damo activity batch experiments were conducted to investigate the presence and diversity of M. oxyfera bacteria in paddy field, corn field, and wastewater treatment plant (WWTP) sites in northern China, as well as lab-scale n-damo enrichment culture. N-damo enrichment culture showed the highest abundance of M. oxyfera bacteria, and positive correlation was observed between potential n-damo rate and abundance of M. oxyfera bacteria. Both paddy field and corn field sites were believed to be better inoculum than WWTP for the enrichment of M. oxyfera bacteria due to their higher abundance and the diversity of M. oxyfera bacteria. Comparative analysis revealed that long biomass retention time, low NH\documentclass[12pt]{minimal}
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Affiliation(s)
- Zhen Hu
- School of Environmental Science and Engineering, Shandong University , Jinan , China
| | - Ru Ma
- School of Environmental Science and Engineering, Shandong University , Jinan , China
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17
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Ren Y, Wang J, Xu L, Liu C, Zong R, Yu J, Liang S. Direct emissions of N2O, CO 2, and CH 4 from A/A/O bioreactor systems: impact of influent C/N ratio. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:8163-8173. [PMID: 25850740 DOI: 10.1007/s11356-015-4408-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 03/18/2015] [Indexed: 06/04/2023]
Abstract
Direct emissions of N2O, CO2, and CH4, three important greenhouse gases (GHGs), from biological sewage treatment process have attracted increasing attention worldwide, due to the increasing concern about climate change. Despite the tremendous efforts devoted to understanding GHG emission from biological sewage treatment process, the impact of influent C/N ratios, in terms of chemical oxygen demand (COD)/total nitrogen (TN), on an anaerobic/anoxic/oxic (A/A/O) bioreactor system has not been investigated. In this work, the direct GHG emission from A/A/O bioreactor systems fed with actual sewage was analyzed under different influent C/N ratios over a 6-month period. The results showed that the variation in influent carbon (160 to 500 mg/L) and nitrogen load (35 to 95 mg/L) dramatically influenced pollutant removal efficiency and GHG production from this process. In the A/A/O bioreactor systems, the GHG production increased from 26-39 to 112-173 g CO2-equivalent as influent C/N ratios decreased from 10.3/10.7 to 3.5/3.8. Taking consideration of pollutant removal efficiency and direct biogenic GHG (N2O, CO2, and CH4) production, the optimum influent C/N ratio was determined to be 7.1/7.5, at which a relatively high pollutant removal efficiency and meanwhile a low level of GHG production (30.4 g CO2-equivalent) can be achieved. Besides, mechanical aeration turned out to be the most significant factor influencing GHG emission from the A/A/O bioreactor systems.
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Affiliation(s)
- Yangang Ren
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, People's Republic of China
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