1
|
Zhang Y, Wang Z, Hu J, Pu C. Intelligent management of carbon emissions of urban domestic sewage based on the Internet of Things. ENVIRONMENTAL RESEARCH 2024; 251:118594. [PMID: 38442818 DOI: 10.1016/j.envres.2024.118594] [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: 10/19/2023] [Revised: 02/05/2024] [Accepted: 02/28/2024] [Indexed: 03/07/2024]
Abstract
Domestic wastewater is one of the major carbon sources that cannot be ignored by human society. Against the background of carbon peaking & carbon neutrality (Double Carbon) goals, the continuous urbanization has put heavy pressure on urban drainage systems. Nevertheless, the complex subjective and objective conditions of drainage systems restrict the field monitoring, measurement, and analysis of drainage systems, which has become a great obstacle to the study of carbon emissions from drainage system. In this paper, 3389 sensor terminals of Internet of Things (IoT) are used to build a field monitoring IoT for urban domestic wastewater methane (CH4) carbon emission, with 21 main districts of Chongqing Municipality in China as the study area. Incorporating Fick's law of diffusion, this field monitoring IoT derives a measurement model for methane carbon emissions based on measured concentrations, and solves the problems of long-term and stable monitoring and measurement of methane gas in complex underground environment. With GIS spatio-temporal analysis used to analyze the spatial and temporal evolution patterns of carbon emissions from septic tanks in drainage systems, it successfully reveals the spatial and temporal distribution of methane carbon emissions from drainage systems in different seasons, as well as the relationship between methane carbon emissions from drainage systems and the latitude of direct sunlight. Applying the DTW method, it quantifies the stability of methane monitoring in drainage systems and evaluates the effects of Sampling Frequency (SF) and Number of Devices Terminal (NDT) on the stability of methane monitoring. Consequently, an intelligent management system for carbon emissions from urban domestic wastewater is constructed on the base of IoT, which integrates methane monitoring, measurement and analysis in septic tanks of drainage systems.
Collapse
Affiliation(s)
- Yanjing Zhang
- School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, China
| | - Zhoufeng Wang
- School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, China; Chongqing Rongguan Science Technologies Co.Ltd., Chongqing 400039, China; State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China.
| | - Jiaxing Hu
- School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, China
| | - Chaodong Pu
- Chongqing Rongguan Science Technologies Co.Ltd., Chongqing 400039, China
| |
Collapse
|
2
|
Chen J, Wang H, Yin W, Wang Y, Lv J, Wang A. Deciphering carbon emissions in urban sewer networks: Bridging urban sewer networks with city-wide environmental dynamics. WATER RESEARCH 2024; 256:121576. [PMID: 38608619 DOI: 10.1016/j.watres.2024.121576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 03/26/2024] [Accepted: 04/05/2024] [Indexed: 04/14/2024]
Abstract
As urbanization accelerates, understanding and managing carbon emissions from urban sewer networks have become crucial for sustainable urban water cycles. This review examines the factors influencing greenhouse gas (GHG) emissions within urban sewage systems, analyzing the complex effects between water quality, hydrodynamics, and sewer infrastructure on GHG production and emission processes. It reveals significant spatiotemporal heterogeneity in GHG emissions, particularly under long-term scenarios where flow rates and temperatures exhibit strong impacts and correlations. Given the presence of fugitive and dissolved potential GHGs, standardized monitoring and accounting methods are deemed essential. Advanced modeling techniques emerge as crucial tools for large-scale carbon emission prediction and management. The review identifies that traditional definitions and computational frameworks for carbon emission boundaries fail to fully consider the inherent heterogeneity of sewers and the dynamic changes and impacts of multi-source pollution within the sewer system during the urban water cycle. This includes irregular fugitive emissions, the influence of stormwater systems, climate change, geographical features, sewer design, and the impacts of food waste and antibiotics. Key strategies for emission management are discussed, focusing on the need for careful consideration of approaches that might inadvertently increase global emissions, such as ventilation, chemical treatments, and water management practices. The review advocates for an overarching strategy that encompasses a holistic view of carbon emissions, stressing the importance of refined emission boundary definitions, novel accounting practices, and comprehensive management schemes in line with the water treatment sector's move towards carbon neutrality. It champions the adoption of interdisciplinary, technologically advanced solutions to mitigate pollution and reduce carbon emissions, emphasizing the importance of integrating cross-scale issues and other environmentally friendly measures in future research directions.
Collapse
Affiliation(s)
- Jiaji Chen
- Key Lab of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 101408, China; State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China; Sino-Danish Center for Education and Research, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Hongcheng Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
| | - Wanxin Yin
- College of the Environment, Liaoning University, Shenyang 110036, China
| | - Yuqi Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Jiaqiang Lv
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - AiJie Wang
- Key Lab of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
| |
Collapse
|
3
|
Zuo Z, Xing Y, Duan H, Ren D, Zheng M, Liu Y, Huang X. Reducing sulfide and methane production in gravity sewer sediments through urine separation, collection and intermittent dosing. WATER RESEARCH 2023; 234:119820. [PMID: 36889087 DOI: 10.1016/j.watres.2023.119820] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Revised: 02/21/2023] [Accepted: 02/25/2023] [Indexed: 06/18/2023]
Abstract
Sulfide and methane production are a major concern in sewer management. Many solutions with the use of chemicals have been proposed yet incurring huge costs. Here, this study reports an alternative solution to reduce sulfide and methane production in sewer sediments. This is achieved through integration of urine source separation, rapid storage, and intermittent in situ re-dosing into a sewer. Based on a reasonable capacity of urine collection, an intermittent dosing strategy (i.e. 40 min per day) was designed and then experimentally tested using two laboratory sewer sediment reactors. The long-term operation showed that the proposed urine dosing in the experimental reactor effectively reduced sulfidogenic and methanogenic activities by 54% and 83%, compared to those in the control reactor. In-sediment chemical and microbial analyses revealed that the short-term exposure to urine wastewater was effective in suppressing sulfate-reducing bacteria and methanogenic archaea, particularly within a surface active zone of sediments (0-0.5 cm) likely attributed to the biocidal effect of urine free ammonia. Economic and environmental assessments indicated that the proposed urine approach can save 91% in total costs, 80% in energy consumption and 96% in greenhouse gas emissions compared to the conventional use of chemicals (including ferric salt, nitrate, sodium hydroxide, and magnesium hydroxide). These results collectively demonstrated a practical solution without chemical input to improve sewer management.
Collapse
Affiliation(s)
- Zhiqiang Zuo
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia; National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yaxin Xing
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Haoran Duan
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Daheng Ren
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Min Zheng
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Yanchen Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| |
Collapse
|
4
|
Ren D, Zuo Z, Xing Y, Ji P, Yu T, Zhu D, Liu Y, Huang X. Simultaneous control of sulfide and methane in sewers achieved by a physical approach targeting dominant active zone in sediments. WATER RESEARCH 2022; 211:118010. [PMID: 35021123 DOI: 10.1016/j.watres.2021.118010] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/26/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
Sewer sediments not only induce sewer blockages, but also contributes to significant sulfide and methane productions in gravity sewer systems. Chemical control of sulfide and methane production is extremely expensive. This study aims to propose a novel physical control approach-intermittent surface sediment flushing to synchronously address sediment-induced multiple issues. The proposed approach was established investigating the suppression and recovery characteristics of sulfidogenic and methanogenic activities of sediments including the in-situ activity analysis by using the diffusive gradients in thin films (DGT). The results showed that ∼70% of total sulfide and methane production in sediments was contributed by surface sediments (0-1.5 cm), which could be easily flushed away by a low shear stress (<0.1 N/m2). Surface sediment flushing resulted in an immediate reduction in sulfidogenic and methanogenic activities, which both required about one week to recover to 50% of the maximum. These novel insights hopefully provide a feasible approach, i.e., intermittent surface sediment flushing, to effectively reduce sulfide and methane production in sewers. Compared with chemical dosing methods, the proposed approach, which has no chemical input, greatly reduces operating cost and environment impact. Moreover, intermittent surface flushing is expected to keep sediment thickness within a certain range to alleviate sewer blockage.
Collapse
Affiliation(s)
- Daheng Ren
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhiqiang Zuo
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yaxin Xing
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Penghui Ji
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Tong Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - David Zhu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Yanchen Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| |
Collapse
|
5
|
Zuo Z, Ren D, Qiao L, Li H, Huang X, Liu Y. Rapid dynamic quantification of sulfide generation flux in spatially heterogeneous sediments of gravity sewers. WATER RESEARCH 2021; 203:117494. [PMID: 34412021 DOI: 10.1016/j.watres.2021.117494] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/20/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Compared with anaerobic pressure sewers, gravity sewers have much more complex operational conditions, such as anaerobic/aerobic spatial variations along variable structures of the pipe network. This greatly complicates the prediction of sulfide generation from spatially heterogeneous sewer sediments. This study proposes a novel quantitative approach for rapidly estimating the sulfide generation flux by understanding the sulfidogenic conversion under complex sewer conditions. Significant anaerobic/aerobic spatial variations were the most critical factor affecting the sulfide production in residential gravity sewers. The dynamic aeration-related process stimulated the growth of sulfide-oxidizing bacteria (SOB) in the surface zone, while the sulfidogenic and methanogenic zone moved into deeper layers. A detailed mechanism model incorporating dynamic alternative anaerobic/aerobic transformation was developed to predict apparent sulfide production, as well as the microscale spatial profiles of chemicals and microbial communities in sediments. The model was evaluated to establish a rapid quantitative approach that only depended on a few key parameters (e.g., flow velocity, pipe diameter, slope, mean hydraulic depth and sulfate concentration), which can provide an important basis for estimating different sulfide generation fluxes under various sewer factors. The identification of sulfide generation hotspots will greatly help determine how to economically control sulfide generation by chemical dosing or pipe structural modification.
Collapse
Affiliation(s)
- Zhiqiang Zuo
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Daheng Ren
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Longkai Qiao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - He Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanchen Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
| |
Collapse
|