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2024 Vol. 42, No. 4
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2024, 42(4): 1-8.
doi: 10.13205/j.hjgc.202404001
Abstract:
The research was focused on Hangzhou Bay (HB) in the East China Sea, a region characterized by severe water pollution. The composition and distribution of 77 antibiotics belonging to 6 classes, in sewage treatment plants, near-shore effluent receiving areas, and coastal waters were investigated using high-performance liquid chromatography-mass spectrometry. The findings revealed that the removal rates of antibiotics in sewage treatment plants ranged from 31.1% to 88.8%, with quinolones exhibiting the highest removal rate at an average value of 80.3%. Effluent from the sewage treatment plants was discharged into the corresponding effluent receiving areas. In the Jiaxing (JX) effluent receiving area, 53 antibiotics were identified with an average concentration of 48180.7 ng/L, while the Shangyu (SY) effluent receiving area contained 63 antibiotics with an average concentration of 341.2 ng/L. The result of the principal component analysis indicated that the sewage treatment plant was a significant source of antibiotic pollution in the SY effluent receiving area. In contrast, the antibiotics in the JX effluent receiving area were less influenced by the sewage treatment plant discharge and more affected by other sources containing veterinary antibiotics. Following the collection of antibiotic-containing wastewater, the near-shore effluent receiving areas became a "source" of antibiotic pollution in the coastal sea. The waterin coastal area contained 51 antibiotics with an average concentration of 189.5 ng/L. A clear "distance attenuation" trend was observed in the diffusion of antibiotic concentration from near-shore to coastal areas, particularly for quinolone antibiotics.
The research was focused on Hangzhou Bay (HB) in the East China Sea, a region characterized by severe water pollution. The composition and distribution of 77 antibiotics belonging to 6 classes, in sewage treatment plants, near-shore effluent receiving areas, and coastal waters were investigated using high-performance liquid chromatography-mass spectrometry. The findings revealed that the removal rates of antibiotics in sewage treatment plants ranged from 31.1% to 88.8%, with quinolones exhibiting the highest removal rate at an average value of 80.3%. Effluent from the sewage treatment plants was discharged into the corresponding effluent receiving areas. In the Jiaxing (JX) effluent receiving area, 53 antibiotics were identified with an average concentration of 48180.7 ng/L, while the Shangyu (SY) effluent receiving area contained 63 antibiotics with an average concentration of 341.2 ng/L. The result of the principal component analysis indicated that the sewage treatment plant was a significant source of antibiotic pollution in the SY effluent receiving area. In contrast, the antibiotics in the JX effluent receiving area were less influenced by the sewage treatment plant discharge and more affected by other sources containing veterinary antibiotics. Following the collection of antibiotic-containing wastewater, the near-shore effluent receiving areas became a "source" of antibiotic pollution in the coastal sea. The waterin coastal area contained 51 antibiotics with an average concentration of 189.5 ng/L. A clear "distance attenuation" trend was observed in the diffusion of antibiotic concentration from near-shore to coastal areas, particularly for quinolone antibiotics.
2024, 42(4): 9-21.
doi: 10.13205/j.hjgc.202404002
Abstract:
Municipal wastewater treatment plants (MWWTPs) are regarded as one of the important nitrous oxide (N2O) emission sources. In this paper, emission characteristics of N2O from different areas and various treatment processes were summarized. Meanwhile, N2O mitigation strategies concerning the optimization of operation parameters as well as the development and application of novel technologies were proposed. According to previous studies, N2O emission from MWWTPs in East China was higher than that in West China. Moreover, N2O emission through wastewater treatment processes was higher than that from sludge treatment systems. In the context of achieving the "carbon peaking and carbon neutrality" goals of China, N2O mitigation should not be realized at the expense of producing by-products like NO and increasing energy consumption. Engineering measures, such as sealing the reaction tanks and installing accurate aeration systems, could reduce N2O emissions from MWWTPs without a substantial increase in electricity expense. Promoting industrialization of novel technologies (including but not limited to aerobic granular sludge, anaerobic ammonium oxidation, and coupled aerobic-anoxic nitrous decomposition operation), along with building N2O reduction facilities for tailwater and sidestream treatment could promote the realization of net zero carbon emission MWWTPs. In general, operation parameters optimization and novel technology development are profitable for N2O mitigation, which is of far-reaching significance for actualizing the low-carbon operation of MWWTPs.
Municipal wastewater treatment plants (MWWTPs) are regarded as one of the important nitrous oxide (N2O) emission sources. In this paper, emission characteristics of N2O from different areas and various treatment processes were summarized. Meanwhile, N2O mitigation strategies concerning the optimization of operation parameters as well as the development and application of novel technologies were proposed. According to previous studies, N2O emission from MWWTPs in East China was higher than that in West China. Moreover, N2O emission through wastewater treatment processes was higher than that from sludge treatment systems. In the context of achieving the "carbon peaking and carbon neutrality" goals of China, N2O mitigation should not be realized at the expense of producing by-products like NO and increasing energy consumption. Engineering measures, such as sealing the reaction tanks and installing accurate aeration systems, could reduce N2O emissions from MWWTPs without a substantial increase in electricity expense. Promoting industrialization of novel technologies (including but not limited to aerobic granular sludge, anaerobic ammonium oxidation, and coupled aerobic-anoxic nitrous decomposition operation), along with building N2O reduction facilities for tailwater and sidestream treatment could promote the realization of net zero carbon emission MWWTPs. In general, operation parameters optimization and novel technology development are profitable for N2O mitigation, which is of far-reaching significance for actualizing the low-carbon operation of MWWTPs.
2024, 42(4): 22-30.
doi: 10.13205/j.hjgc.202404003
Abstract:
Municipal sewers are an important potential source of greenhouse gases such as methane, with a wide range of influencing factors. The characteristics of methane production and discharge in pipelines, the transformation of substrates and the microbial function mechanisms under different water quality conditions still need to be further analyzed. This study investigated the volatile fatty acids (VFAs) content and methane emission characteristics in sewage pipeline systems under different sewage concentrations (100~700 mg COD/L) via static simulations. The results showed that the higher the effluent COD concentration in the pipeline system, the higher the production of VFAs and methane. Compared with low-concentration sewage (100 mg COD/L), the VFAs production in high-concentration sewage pipeline systems (500 and 700 mg COD/L) was increased by 2.4, 4.1 times, respectively, while the methane emission was increased by 8.1 and 21.0 times. Mechanism analysis revealed that high-concentration sewage in the pipeline system favored the enrichment of anaerobic microorganisms involved in hydrolysis, acidogenesis, and methane production. This led to the upregulation of functional gene expression associated with extracellular hydrolysis (e.g., dacC), intracellular metabolism (e.g., yhdR), fatty acid generation (e.g., pta), and methane generation (e.g., ftr, fwd), thereby enhancing microbial methane production metabolism. Partial least squares path modeling (PLS-PM) analysis indicated that the functional microbial community (λ=0.721) and the expression of related metabolic genes (λ=0.640) were the main factors influencing methane production and emission in sewage pipelines, while sewage COD concentration was a secondary factor (λ=0.623).
Municipal sewers are an important potential source of greenhouse gases such as methane, with a wide range of influencing factors. The characteristics of methane production and discharge in pipelines, the transformation of substrates and the microbial function mechanisms under different water quality conditions still need to be further analyzed. This study investigated the volatile fatty acids (VFAs) content and methane emission characteristics in sewage pipeline systems under different sewage concentrations (100~700 mg COD/L) via static simulations. The results showed that the higher the effluent COD concentration in the pipeline system, the higher the production of VFAs and methane. Compared with low-concentration sewage (100 mg COD/L), the VFAs production in high-concentration sewage pipeline systems (500 and 700 mg COD/L) was increased by 2.4, 4.1 times, respectively, while the methane emission was increased by 8.1 and 21.0 times. Mechanism analysis revealed that high-concentration sewage in the pipeline system favored the enrichment of anaerobic microorganisms involved in hydrolysis, acidogenesis, and methane production. This led to the upregulation of functional gene expression associated with extracellular hydrolysis (e.g., dacC), intracellular metabolism (e.g., yhdR), fatty acid generation (e.g., pta), and methane generation (e.g., ftr, fwd), thereby enhancing microbial methane production metabolism. Partial least squares path modeling (PLS-PM) analysis indicated that the functional microbial community (λ=0.721) and the expression of related metabolic genes (λ=0.640) were the main factors influencing methane production and emission in sewage pipelines, while sewage COD concentration was a secondary factor (λ=0.623).
2024, 42(4): 31-39.
doi: 10.13205/j.hjgc.202404004
Abstract:
The composition of leachate from municipal solid waste (MSW) incineration is complex and has high concentrations of pollutants, making its treatment system an important source of greenhouse gas emissions. However, the carbon emission characteristics of the incineration leachate treatment system are still not clear, which hinders the development and implementation of pollution reduction and carbon reduction strategies. Therefore, in this study, the inclination leachate from a typical MSW incineration plant in Shanghai was selected as the research object. The carbon footprint of the incineration leachate treatment system was calculated using a life cycle assessment method. The study focused on the carbon emission characteristics of the leachate treatment system under different water quality and quantity conditions. The carbon emissions of different treatment units were quantitatively analyzed to provide a scientific basis for upgrading and transforming low-carbon treatment processes for incineration leachate and achieving coordinated pollution reduction and carbon reduction goals in China. The results showed that direct carbon emissions tended to be higher in spring and summer and lower in autumn and winter, with N2O being the most important direct carbon emission source (0.4~47.7 t CO2 eq); indirect carbon emissions were much higher than direct carbon emissions, with electricity being the largest source of carbon emissions (78.2~121.3 t CO2 eq). In addition, external carbon sources could reduce direct carbon emissions to some extent but would increase indirect carbon emissions. Recovering CH4 generated in the anaerobic digestion (AD) unit (0~160.3 t CO2 eq) is an important pathway for achieving carbon neutrality in the leachate treatment system. Although the direct and indirect carbon emissions were reduced after waste classification, the limited carbon recovery led to an increase in net carbon emissions from the leachate treatment plant, causing the leachate treatment system a transition from a carbon sink to a carbon source. Overall, in the carbon reduction strategy for the incineration leachate treatment system, it is crucial to focus on controlling carbon emissions from electricity. Reducing direct carbon emissions can be achieved by improving denitrification efficiency. Upgrading and improving the two-stage anoxic/oxic(A/O) process in each leachate treatment unit is essential for achieving energy savings and emissions reduction.
The composition of leachate from municipal solid waste (MSW) incineration is complex and has high concentrations of pollutants, making its treatment system an important source of greenhouse gas emissions. However, the carbon emission characteristics of the incineration leachate treatment system are still not clear, which hinders the development and implementation of pollution reduction and carbon reduction strategies. Therefore, in this study, the inclination leachate from a typical MSW incineration plant in Shanghai was selected as the research object. The carbon footprint of the incineration leachate treatment system was calculated using a life cycle assessment method. The study focused on the carbon emission characteristics of the leachate treatment system under different water quality and quantity conditions. The carbon emissions of different treatment units were quantitatively analyzed to provide a scientific basis for upgrading and transforming low-carbon treatment processes for incineration leachate and achieving coordinated pollution reduction and carbon reduction goals in China. The results showed that direct carbon emissions tended to be higher in spring and summer and lower in autumn and winter, with N2O being the most important direct carbon emission source (0.4~47.7 t CO2 eq); indirect carbon emissions were much higher than direct carbon emissions, with electricity being the largest source of carbon emissions (78.2~121.3 t CO2 eq). In addition, external carbon sources could reduce direct carbon emissions to some extent but would increase indirect carbon emissions. Recovering CH4 generated in the anaerobic digestion (AD) unit (0~160.3 t CO2 eq) is an important pathway for achieving carbon neutrality in the leachate treatment system. Although the direct and indirect carbon emissions were reduced after waste classification, the limited carbon recovery led to an increase in net carbon emissions from the leachate treatment plant, causing the leachate treatment system a transition from a carbon sink to a carbon source. Overall, in the carbon reduction strategy for the incineration leachate treatment system, it is crucial to focus on controlling carbon emissions from electricity. Reducing direct carbon emissions can be achieved by improving denitrification efficiency. Upgrading and improving the two-stage anoxic/oxic(A/O) process in each leachate treatment unit is essential for achieving energy savings and emissions reduction.
2024, 42(4): 40-47.
doi: 10.13205/j.hjgc.202404005
Abstract:
As a potential source of groundwater pollution, landfill sites may still cause significant pollution risks to surrounding groundwater due to leachate leakage after closure. Therefore, studying the pollutant transport patterns after leachate leakage in landfill sites is of great significance for managing landfill sites after closure and monitoring groundwater pollution. In this paper, we established a water flow and solute transport model based on Visual Modflow, considering only the abnormal condition of long-term continuous leakage at the bottom of a landfill site, to predict the transport and diffusion laws of typical pollutants (COD) in domestic landfills. The research results indicate that the groundwater flow in the study area flows from north to south, and COD leaks and then migrates downstream; the long-term continuous leakage at the bottom of the landfill area continuously increases the diffusion range, distance, and maximum concentration of the pollution plume. By the 3650th day, it has exceeded the boundary of the research area, causing pollution to the CY River on the right side. Therefore, after discovering the leakage, it is necessary to take effective measures promptly, such as gas phase extraction, PRB technology, etc., to avoid the continued migration and diffusion of pollutants; it is necessary to strengthen the monitoring of groundwater in the landfill and its surrounding areas, regularly inspect and maintain groundwater monitoring wells, and establish a reasonable emergency response mechanism.
As a potential source of groundwater pollution, landfill sites may still cause significant pollution risks to surrounding groundwater due to leachate leakage after closure. Therefore, studying the pollutant transport patterns after leachate leakage in landfill sites is of great significance for managing landfill sites after closure and monitoring groundwater pollution. In this paper, we established a water flow and solute transport model based on Visual Modflow, considering only the abnormal condition of long-term continuous leakage at the bottom of a landfill site, to predict the transport and diffusion laws of typical pollutants (COD) in domestic landfills. The research results indicate that the groundwater flow in the study area flows from north to south, and COD leaks and then migrates downstream; the long-term continuous leakage at the bottom of the landfill area continuously increases the diffusion range, distance, and maximum concentration of the pollution plume. By the 3650th day, it has exceeded the boundary of the research area, causing pollution to the CY River on the right side. Therefore, after discovering the leakage, it is necessary to take effective measures promptly, such as gas phase extraction, PRB technology, etc., to avoid the continued migration and diffusion of pollutants; it is necessary to strengthen the monitoring of groundwater in the landfill and its surrounding areas, regularly inspect and maintain groundwater monitoring wells, and establish a reasonable emergency response mechanism.
2024, 42(4): 48-57.
doi: 10.13205/j.hjgc.202404006
Abstract:
The presence of a significant amount of residual food in landfills attracts birds to forage, inadvertently leading to the transportation of pollutants, such as plastics, heavy metals, and pathogens into their habitats, potentially impacting the local ecological environment. Drawing upon existing literature, this review examines the role of birds in the migration of pollutants within landfills, providing a detailed analysis of the specific pathways through which plastics, heavy metals, and antibiotic-resistant bacteria are transmitted by birds, and their negative impacts on the environment. Furthermore, targeted recommendations for future landfill management are proposed based on the reasons for bird entry into landfills. The aim is to protect avian ecology while effectively reducing the transmission risk and severity of pollutants within landfills.
The presence of a significant amount of residual food in landfills attracts birds to forage, inadvertently leading to the transportation of pollutants, such as plastics, heavy metals, and pathogens into their habitats, potentially impacting the local ecological environment. Drawing upon existing literature, this review examines the role of birds in the migration of pollutants within landfills, providing a detailed analysis of the specific pathways through which plastics, heavy metals, and antibiotic-resistant bacteria are transmitted by birds, and their negative impacts on the environment. Furthermore, targeted recommendations for future landfill management are proposed based on the reasons for bird entry into landfills. The aim is to protect avian ecology while effectively reducing the transmission risk and severity of pollutants within landfills.
2024, 42(4): 58-65.
doi: 10.13205/j.hjgc.202404007
Abstract:
To solve the current problem of lagging construction of reclaimed water-supply networks in China, the distribution of reclaimed water using heat-supply networks was proposed. The application situations of reclaimed water distribution through a heat-supply network were analyzed, and the risk types and factors were identified, and then the control methods also were proposed. Chem-corrosion, bio-corrosion, scaling and yellow water were the main risks of the reclaimed water distribution by heat-supply network. Reclaimed water with grade A level could be the preferred water source for the heat-supply replenishment. The risk factors of the reclaimed water distribution by the heat-supply network for industrial reuse mainly included pH, inorganic and organic matters. Besides the above risk factors, nutrients and heavy metals were also included for the landscape environment, municipal and agricultural reuse. The essential control methods of the reclaimed water distribution by the heat-supply network were water softening, de-oxygen, and organic matter removal. In addition, the key control points for each situation were the removal of nutrients and heavy metals, reduction of Larsen index, and proportional switching of water sources. Then the feasibility of above application situations and control methods was analyzed in a case in Taiyuan as an example. It could provide theoretical basis and technical reference for the reclaimed water distribution by the heat-supply network.
To solve the current problem of lagging construction of reclaimed water-supply networks in China, the distribution of reclaimed water using heat-supply networks was proposed. The application situations of reclaimed water distribution through a heat-supply network were analyzed, and the risk types and factors were identified, and then the control methods also were proposed. Chem-corrosion, bio-corrosion, scaling and yellow water were the main risks of the reclaimed water distribution by heat-supply network. Reclaimed water with grade A level could be the preferred water source for the heat-supply replenishment. The risk factors of the reclaimed water distribution by the heat-supply network for industrial reuse mainly included pH, inorganic and organic matters. Besides the above risk factors, nutrients and heavy metals were also included for the landscape environment, municipal and agricultural reuse. The essential control methods of the reclaimed water distribution by the heat-supply network were water softening, de-oxygen, and organic matter removal. In addition, the key control points for each situation were the removal of nutrients and heavy metals, reduction of Larsen index, and proportional switching of water sources. Then the feasibility of above application situations and control methods was analyzed in a case in Taiyuan as an example. It could provide theoretical basis and technical reference for the reclaimed water distribution by the heat-supply network.
2024, 42(4): 66-73.
doi: 10.13205/j.hjgc.202404008
Abstract:
After the full implementation of ultra-low emission in coal-fired power plants, whether it is still necessary to adopt high stack emission has aroused extensive discussion. In this study, taking the Yiyang Power Plant as an example, the impact of six scenarios based on two emission heights (210 m, 60 m) on the concentrations of air pollutants at the state-controlled monitoring sites in Yiyang were simulated using the AERMOD model. The results showed that in both typical and unfavorable meteorological years, the temporary chimney with a height of 60 m has an adverse effect on the concentrations of air pollutants at each monitoring site, compared to the original chimney with a height of 210 m, resulting in an increase in the maximum daily concentrations of each pollutant in the range of 8.82 μg/m3 to 20.19 μg/m3, and an increase in the maximum annual concentrations of each pollutant in the range of 0.91 to 2.08 μg/m3, and the effect in unfavorable meteorological years was generally greater than that in typical meteorological years. At the same time, the change in emission altitude also has an important effect on the maximum occupancy rate of pollutants and the number of days of pollution exceedance in Yiyang. The maximum occupancy rate of NO2 and PM2.5 increased significantly, and the number of days of particulate matter exceedance increased by more than or equal to 2 days in several monitoring sites. Because coal-fired power generation is still the dominant power source of China, as well as the urgent need for air quality improvement, a significant reduction in the height of emission stacks should be considered prudently.
After the full implementation of ultra-low emission in coal-fired power plants, whether it is still necessary to adopt high stack emission has aroused extensive discussion. In this study, taking the Yiyang Power Plant as an example, the impact of six scenarios based on two emission heights (210 m, 60 m) on the concentrations of air pollutants at the state-controlled monitoring sites in Yiyang were simulated using the AERMOD model. The results showed that in both typical and unfavorable meteorological years, the temporary chimney with a height of 60 m has an adverse effect on the concentrations of air pollutants at each monitoring site, compared to the original chimney with a height of 210 m, resulting in an increase in the maximum daily concentrations of each pollutant in the range of 8.82 μg/m3 to 20.19 μg/m3, and an increase in the maximum annual concentrations of each pollutant in the range of 0.91 to 2.08 μg/m3, and the effect in unfavorable meteorological years was generally greater than that in typical meteorological years. At the same time, the change in emission altitude also has an important effect on the maximum occupancy rate of pollutants and the number of days of pollution exceedance in Yiyang. The maximum occupancy rate of NO2 and PM2.5 increased significantly, and the number of days of particulate matter exceedance increased by more than or equal to 2 days in several monitoring sites. Because coal-fired power generation is still the dominant power source of China, as well as the urgent need for air quality improvement, a significant reduction in the height of emission stacks should be considered prudently.
2024, 42(4): 74-81.
doi: 10.13205/j.hjgc.202404009
Abstract:
The basin compound ecosystem consists of the socioeconomic system and natural water system. Exploring the effects of production and consumption pattern transitions within and outside the basin on water uses in the basin can provide new insights into water resource management of the basin compound ecosystem. Based on the environmentally extended multi-regional input-output model and structural decomposition analysis, this study investigated the effects of China’s multi-regional transitions of production and consumption patterns on water use changes in the Pearl River Basin from 2007 to 2017. Results showed that the final demand from outside the basin drove 20% to 23% of water use in the Pearl River Basin. Zhejiang and Hebei contributed significantly to the water use increments in the Pearl River Basin. In contrast, Shanghai and Beijing were vital in reducing water use. These two provinces contributed even more than those within the basin (except for Guangxi and Guangdong), mainly attributed to their optimizations of the final demand structure. The decline in water use intensity is a critical factor contributing to the water use reductions in the Pearl River Basin. However, in addition to improving water use efficiency within the basin, it is urgent to break through the end-of-pipe control-oriented approach for water resource management. This study proposed that water resource management in the Pearl River Basin should take a multi-regional compound ecosystem perspective. Policymakers should pay attention to collaborative transitions of production and consumption patterns of both in-basin and out-of-basin regions, and reduce water uses of the whole supply chain from the demand perspective.
The basin compound ecosystem consists of the socioeconomic system and natural water system. Exploring the effects of production and consumption pattern transitions within and outside the basin on water uses in the basin can provide new insights into water resource management of the basin compound ecosystem. Based on the environmentally extended multi-regional input-output model and structural decomposition analysis, this study investigated the effects of China’s multi-regional transitions of production and consumption patterns on water use changes in the Pearl River Basin from 2007 to 2017. Results showed that the final demand from outside the basin drove 20% to 23% of water use in the Pearl River Basin. Zhejiang and Hebei contributed significantly to the water use increments in the Pearl River Basin. In contrast, Shanghai and Beijing were vital in reducing water use. These two provinces contributed even more than those within the basin (except for Guangxi and Guangdong), mainly attributed to their optimizations of the final demand structure. The decline in water use intensity is a critical factor contributing to the water use reductions in the Pearl River Basin. However, in addition to improving water use efficiency within the basin, it is urgent to break through the end-of-pipe control-oriented approach for water resource management. This study proposed that water resource management in the Pearl River Basin should take a multi-regional compound ecosystem perspective. Policymakers should pay attention to collaborative transitions of production and consumption patterns of both in-basin and out-of-basin regions, and reduce water uses of the whole supply chain from the demand perspective.
2024, 42(4): 82-90.
doi: 10.13205/j.hjgc.202404010
Abstract:
It is very important to carry out the risk assessment of rainstorm-induced inundation in urban areas for inundation regulation and urban security development. This study took the 310 km2 main urban area of Yinchuan as an example, to establish an efficient and high-resolution coupled GAST-SWMM model of urban surface inundation and drainage process of underground pipe network based on GPU acceleration technology. The model was verified by the measured information of inundation points. The inundation location and risk level before and after the planning of the study area were simulated respectively under the condition of 24-hour rainstorms with a return period of 20 years and 30 years. The inundation reduction was analyzed and the inundation risk map was drawn. The results showed that compared with the measured values, the simulation error of the model was less than 6%, and the simulation accuracy was higher. After planning, compared with the situation before planning, the average value of the peak water area reduction rate and peak water depth reduction rate reached 41.6% and 45.03%, respectively, and the average value of the peak water depth reduction rate reached 51.74% and 56.05%, respectively, and the high-risk water points were all reduced to medium risk and low risk. The coupled numerical model has a good application effect in the large-scale urban rainstorm-induced inundation risk assessment, and the research results have important reference value for the prevention and elimination of rainstorm-prone inundation points in Yinchuan.
It is very important to carry out the risk assessment of rainstorm-induced inundation in urban areas for inundation regulation and urban security development. This study took the 310 km2 main urban area of Yinchuan as an example, to establish an efficient and high-resolution coupled GAST-SWMM model of urban surface inundation and drainage process of underground pipe network based on GPU acceleration technology. The model was verified by the measured information of inundation points. The inundation location and risk level before and after the planning of the study area were simulated respectively under the condition of 24-hour rainstorms with a return period of 20 years and 30 years. The inundation reduction was analyzed and the inundation risk map was drawn. The results showed that compared with the measured values, the simulation error of the model was less than 6%, and the simulation accuracy was higher. After planning, compared with the situation before planning, the average value of the peak water area reduction rate and peak water depth reduction rate reached 41.6% and 45.03%, respectively, and the average value of the peak water depth reduction rate reached 51.74% and 56.05%, respectively, and the high-risk water points were all reduced to medium risk and low risk. The coupled numerical model has a good application effect in the large-scale urban rainstorm-induced inundation risk assessment, and the research results have important reference value for the prevention and elimination of rainstorm-prone inundation points in Yinchuan.
2024, 42(4): 91-99.
doi: 10.13205/j.hjgc.202404011
Abstract:
Parabens are widely used as preservatives in the production of food, cosmetics, pharmaceuticals, and industrial products. However, as a group of emerging endocrine disruptor, parabens can be bioaccumulated in aquatic organisms, thus posing threat to the ecosystem and human health. In this study, we investigated the occurrence and distribution of parabens in the surface water and sediments of the Dongjiang River, and assessed the potential ecological risk it may pose. The results showed that the concentrations of total parabens in the surface water ranged from 1.17 ng/L to 17.07 ng/L. The concentrations of parabens in sediments ranged from 19.0 ng/g to 765.959 ng/g. Meanwhile, the average content of parabens in the water column and sediment of Xizhijiang (XZJ) was higher, 3.62 ng/L and 155.99 ng/g, respectively. Among the parabens and metabolites measured, MeP and 4-HB were the respective major parent compound and metabolite. The levels of different types of parent parabens also showed variability in different regions, which may be related to different consumption habits of food, drugs, and cosmetics. The risk assessment showed that the ecological risk of parabens in the Dongjiang River was low, but long-term exposure may cause greater harmful effects on the ecosystem. The results of the study provide scientific support for the risk assessment and environmental management of parabens.
Parabens are widely used as preservatives in the production of food, cosmetics, pharmaceuticals, and industrial products. However, as a group of emerging endocrine disruptor, parabens can be bioaccumulated in aquatic organisms, thus posing threat to the ecosystem and human health. In this study, we investigated the occurrence and distribution of parabens in the surface water and sediments of the Dongjiang River, and assessed the potential ecological risk it may pose. The results showed that the concentrations of total parabens in the surface water ranged from 1.17 ng/L to 17.07 ng/L. The concentrations of parabens in sediments ranged from 19.0 ng/g to 765.959 ng/g. Meanwhile, the average content of parabens in the water column and sediment of Xizhijiang (XZJ) was higher, 3.62 ng/L and 155.99 ng/g, respectively. Among the parabens and metabolites measured, MeP and 4-HB were the respective major parent compound and metabolite. The levels of different types of parent parabens also showed variability in different regions, which may be related to different consumption habits of food, drugs, and cosmetics. The risk assessment showed that the ecological risk of parabens in the Dongjiang River was low, but long-term exposure may cause greater harmful effects on the ecosystem. The results of the study provide scientific support for the risk assessment and environmental management of parabens.
2024, 42(4): 100-110.
doi: 10.13205/j.hjgc.202404012
Abstract:
Compared the denitrification performance of single-stage moving bed biofilm reactors (MBBR) under two different operation modes, continuous flow, and sequencing batch, by adding synthetic wastewater with different carbon-to-nitrogen(C/N) ratios. Metagenomic sequencing technology was utilized to analyze the microbial community and functional gene abundance of biofilms on carriers in different phases, as well as to analyze the major nitrogen metabolism pathways in the reactor, with the aim of investigating the effects of different C/N ratios and operation modes on the denitrification performance and biofilm community structure of the MBBR system. Results showed that the variation of C/N ratio had little effect on ammonia nitrogen removal of the MBBR process, with ammonia nitrogen removal rates remaining above 95% in all phases. However, there was a significant difference in simultaneous nitrification and denitrification (SND) efficiencies among phases, due to the limitation of denitrification performance. In addition, the total inorganic nitrogen removal rate of the sequencing batch MBBR (SBMBBR) was always higher than that of the continuous flow MBBR (CFMBBR), which may be due to the differences in the total number of functional genes, such as narGHI, napAB, nirK, nirS, norBC, and nosZ, which play a crucial role in denitrification. There were significant differences in the dominant bacterial phyla and species under different operation modes, which was also a major reason for the significant difference in denitrification performance between SBMBBR and CFMBBR. These results can provide useful references for the optimization design and operation of MBBR for the treatment of urban domestic wastewater with lower C/N ratios.
Compared the denitrification performance of single-stage moving bed biofilm reactors (MBBR) under two different operation modes, continuous flow, and sequencing batch, by adding synthetic wastewater with different carbon-to-nitrogen(C/N) ratios. Metagenomic sequencing technology was utilized to analyze the microbial community and functional gene abundance of biofilms on carriers in different phases, as well as to analyze the major nitrogen metabolism pathways in the reactor, with the aim of investigating the effects of different C/N ratios and operation modes on the denitrification performance and biofilm community structure of the MBBR system. Results showed that the variation of C/N ratio had little effect on ammonia nitrogen removal of the MBBR process, with ammonia nitrogen removal rates remaining above 95% in all phases. However, there was a significant difference in simultaneous nitrification and denitrification (SND) efficiencies among phases, due to the limitation of denitrification performance. In addition, the total inorganic nitrogen removal rate of the sequencing batch MBBR (SBMBBR) was always higher than that of the continuous flow MBBR (CFMBBR), which may be due to the differences in the total number of functional genes, such as narGHI, napAB, nirK, nirS, norBC, and nosZ, which play a crucial role in denitrification. There were significant differences in the dominant bacterial phyla and species under different operation modes, which was also a major reason for the significant difference in denitrification performance between SBMBBR and CFMBBR. These results can provide useful references for the optimization design and operation of MBBR for the treatment of urban domestic wastewater with lower C/N ratios.
2024, 42(4): 111-118.
doi: 10.13205/j.hjgc.202404013
Abstract:
To improve the shortcomings of the traditional Fenton method, such as narrow pH application range and high iron mud production, the present study developed an Fe(Ⅲ)-nitrilotriacetic acid (NTA)/hydroxylamine (HAm)/H2O2 system for the degradation of azo dye Orange G (OG). Experimental results demonstrated that Fe(Ⅲ)-NTA/HAm/H2O2 system could effectively degrade OG under neutral condition with a degradation rate of 90% above, and ·OH was the dominant reactive species responsible for OG degradation in this system. The degradation rate of OG in the Fe(Ⅲ)-NTA/HAm/H2O2 system decreased with the increase of solution pH. Appropriate increases in Fe(Ⅲ), NTA, HAm, and H2O2 concentrations were beneficial for OG degradation in this system, but excessive addition of these reagents would inhibit OG degradation. The introduction of NTA could expand the pH application range of the traditional Fenton process from acidic to weakly alkaline, and the addition of HAm remarkedly reduced the dosage of Fe by promoting the regeneration of Fe(Ⅱ) in the system. Compared with the traditional Fenton process, this Fe(Ⅲ)-NTA/HAm/H2O2 system showed great potential for practical applications.
To improve the shortcomings of the traditional Fenton method, such as narrow pH application range and high iron mud production, the present study developed an Fe(Ⅲ)-nitrilotriacetic acid (NTA)/hydroxylamine (HAm)/H2O2 system for the degradation of azo dye Orange G (OG). Experimental results demonstrated that Fe(Ⅲ)-NTA/HAm/H2O2 system could effectively degrade OG under neutral condition with a degradation rate of 90% above, and ·OH was the dominant reactive species responsible for OG degradation in this system. The degradation rate of OG in the Fe(Ⅲ)-NTA/HAm/H2O2 system decreased with the increase of solution pH. Appropriate increases in Fe(Ⅲ), NTA, HAm, and H2O2 concentrations were beneficial for OG degradation in this system, but excessive addition of these reagents would inhibit OG degradation. The introduction of NTA could expand the pH application range of the traditional Fenton process from acidic to weakly alkaline, and the addition of HAm remarkedly reduced the dosage of Fe by promoting the regeneration of Fe(Ⅱ) in the system. Compared with the traditional Fenton process, this Fe(Ⅲ)-NTA/HAm/H2O2 system showed great potential for practical applications.
2024, 42(4): 119-124.
doi: 10.13205/j.hjgc.202404014
Abstract:
Considering the non-renewable and indispensable nature of phosphorus resources, the treatment and recovery of phosphorus from phosphogypsum leachate based on the crystallization method of bird droppings has important environmental and economic significance. This paper systematically studied the feasibility of recovering phosphorus in the phosphogypsum leachate from a fertilizer company in Hubei Province and the crystallization optimization. The results showed that the main reaction parameters posed a limited effect on obtaining a higher phosphorus recovery efficiency in a single reaction process, and the maximum phosphorus recovery efficiency was only 67.8%. The latter response surface design experimental results also confirmed that after a certain stage, the increase in pH, n(Mg)/n(P), and n(N)/n(P) did not significantly enhance the phosphorus recovery efficiency. Considering the influence of various factors on phosphorus recovery, the optimal condition parameters were determined as follows: pH=8.6, n(Mg)/n(P)=1.6, n(N)/n(P)=1. Finally, a graded crystallization method was adopted, and after three crystallization cycles, phosphorus recovery efficiency reached 97.9%. After characterizing the products in the phosphorus recovery stage through EPMA, XRD and Minteq modeling analysis, the products were mainly struvite with a small amount of calcium phosphate, and the heavy metal content in struvite was extremely low, ensuring its subsequent application safely in agricultural as a potential fertilizer.
Considering the non-renewable and indispensable nature of phosphorus resources, the treatment and recovery of phosphorus from phosphogypsum leachate based on the crystallization method of bird droppings has important environmental and economic significance. This paper systematically studied the feasibility of recovering phosphorus in the phosphogypsum leachate from a fertilizer company in Hubei Province and the crystallization optimization. The results showed that the main reaction parameters posed a limited effect on obtaining a higher phosphorus recovery efficiency in a single reaction process, and the maximum phosphorus recovery efficiency was only 67.8%. The latter response surface design experimental results also confirmed that after a certain stage, the increase in pH, n(Mg)/n(P), and n(N)/n(P) did not significantly enhance the phosphorus recovery efficiency. Considering the influence of various factors on phosphorus recovery, the optimal condition parameters were determined as follows: pH=8.6, n(Mg)/n(P)=1.6, n(N)/n(P)=1. Finally, a graded crystallization method was adopted, and after three crystallization cycles, phosphorus recovery efficiency reached 97.9%. After characterizing the products in the phosphorus recovery stage through EPMA, XRD and Minteq modeling analysis, the products were mainly struvite with a small amount of calcium phosphate, and the heavy metal content in struvite was extremely low, ensuring its subsequent application safely in agricultural as a potential fertilizer.
2024, 42(4): 125-131.
doi: 10.13205/j.hjgc.202404015
Abstract:
Establishing connecting pipes between main sewer pipes to realize the interconnection of municipal wastewater systems can significantly improve the resilience and safety of the system. Sewer pipe interconnection projects have been carried out in China; however, the key points of planning and design need to be further studied. By combing relevant cases of pipe interconnection at home and abroad, the design principles and key points of sewer network interconnection were studied, including planning surplus capacity for wastewater treatment plants, determining the excess capacity of sewage wastewater treatment plants, designing integrated pumping stations, determining the location of connecting points, constructing the connecting pipe by pipe jacking and shield, and improving maintenance of the connecting pipes. Furthermore, a case study of the wastewater system planning of a city was used to explain the application scenario of sewer network interconnection in detail. This paper can provide a reference for the implementation of sewer network interconnection in the future.
Establishing connecting pipes between main sewer pipes to realize the interconnection of municipal wastewater systems can significantly improve the resilience and safety of the system. Sewer pipe interconnection projects have been carried out in China; however, the key points of planning and design need to be further studied. By combing relevant cases of pipe interconnection at home and abroad, the design principles and key points of sewer network interconnection were studied, including planning surplus capacity for wastewater treatment plants, determining the excess capacity of sewage wastewater treatment plants, designing integrated pumping stations, determining the location of connecting points, constructing the connecting pipe by pipe jacking and shield, and improving maintenance of the connecting pipes. Furthermore, a case study of the wastewater system planning of a city was used to explain the application scenario of sewer network interconnection in detail. This paper can provide a reference for the implementation of sewer network interconnection in the future.
2024, 42(4): 132-138.
doi: 10.13205/j.hjgc.202404016
Abstract:
Organic pollutants could be degraded by KMnO4, and the oxidation process of phosphonates by KMnO4 is still unclear. Herein, using nitrilotris (methylene phosphonic acid, NTMP) as a model pollutant, radical capture experiments and electron paramagnetic resonance (EPR) were used to explore the dominant active oxidizing species in KMnO4 system, and the effects of solution chemical properties (such as pH, coexisting substances, actual water body, etc.) on the degradation of NTMP by KMnO4 were investigated. The results showed that direct oxidation of KMnO4 was the dominant pathway for NTMP degradation, and its degradation was greatly influenced by pH value. The best oxidation performance of NTMP by KMnO4 was obtained at pH=5.0, and 51.4% of NTMP was oxidized into PO3-4, much higher than that in UV/H2O2 and UV/potassium persulfate (PDS) system. No obvious inhibition on the degradation of NTMP was observed in the presence of coexisting substances in water (i.e., SO2-4, NO-3, HCO-3, and humic acid). In addition, KMnO4 also showed a high degradation efficiency on NTMP in actual wastewater, and its selectivity was better than that of free radical systems. The results provide an important reference for the efficient removal of phosphonates from actual wastewater.
Organic pollutants could be degraded by KMnO4, and the oxidation process of phosphonates by KMnO4 is still unclear. Herein, using nitrilotris (methylene phosphonic acid, NTMP) as a model pollutant, radical capture experiments and electron paramagnetic resonance (EPR) were used to explore the dominant active oxidizing species in KMnO4 system, and the effects of solution chemical properties (such as pH, coexisting substances, actual water body, etc.) on the degradation of NTMP by KMnO4 were investigated. The results showed that direct oxidation of KMnO4 was the dominant pathway for NTMP degradation, and its degradation was greatly influenced by pH value. The best oxidation performance of NTMP by KMnO4 was obtained at pH=5.0, and 51.4% of NTMP was oxidized into PO3-4, much higher than that in UV/H2O2 and UV/potassium persulfate (PDS) system. No obvious inhibition on the degradation of NTMP was observed in the presence of coexisting substances in water (i.e., SO2-4, NO-3, HCO-3, and humic acid). In addition, KMnO4 also showed a high degradation efficiency on NTMP in actual wastewater, and its selectivity was better than that of free radical systems. The results provide an important reference for the efficient removal of phosphonates from actual wastewater.
2024, 42(4): 139-147.
doi: 10.13205/j.hjgc.202404017
Abstract:
As a typical industrial city in western China, Lanzhou is having significant ozone pollution situation in recent years, and volatile organic compounds (VOCs) play a key role in the generation of secondary pollutants such as O3 and PM2.5. To study the characteristics and sources of VOCs pollution in Lanzhou, this study selected the VOCs components monitoring data from the monitoring stations of Lanzhou University in downtown area and Xigu Refining and Chemical Industry Zone in the west, and conducted research and comparative analysis on VOCs pollution characteristics and sources of the two stations based on the PMF model. The results showed that the average annual value of VOCs in the central urban area was 32.24×10-9, with the highest concentration in December and the lowest in July; the average annual value of VOCs in the Xigu Refining and Chemical Industry Zone was 70.86×10-9, with the highest concentration in May and the lowest in August; alkanes, alkenes, and halogenated hydrocarbons were the main VOCs composition species in the two regions. The overall VOCs emission level of the Xigu Refining and Chemical Industrial Zone was higher than that of the downtown area, in which the concentration of halogenated hydrocarbons was 2.5 times higher than that of the central urban area, the concentration of olefins and aromatic hydrocarbon was more than 2 times higher, and the pollution level of alkynes was decreased. Overall, the trend of VOCs concentration changes in both areas was higher in winter and spring months, and lower in summer and autumn months. PMF source analysis results showed that vehicle exhaust gas source, oil and gas volatilization source, and organic solvents application source are the three main VOCs sources in the downtown area, while the industrial source was the most important VOCs source in Xigu Refining and Chemical Industrial Zone. Therefore, Lanzhou’s VOCs emission reduction control should be focused on reducing anthropogenic sources such as the petrochemical industry, motor vehicle exhaust, and solvent use.
As a typical industrial city in western China, Lanzhou is having significant ozone pollution situation in recent years, and volatile organic compounds (VOCs) play a key role in the generation of secondary pollutants such as O3 and PM2.5. To study the characteristics and sources of VOCs pollution in Lanzhou, this study selected the VOCs components monitoring data from the monitoring stations of Lanzhou University in downtown area and Xigu Refining and Chemical Industry Zone in the west, and conducted research and comparative analysis on VOCs pollution characteristics and sources of the two stations based on the PMF model. The results showed that the average annual value of VOCs in the central urban area was 32.24×10-9, with the highest concentration in December and the lowest in July; the average annual value of VOCs in the Xigu Refining and Chemical Industry Zone was 70.86×10-9, with the highest concentration in May and the lowest in August; alkanes, alkenes, and halogenated hydrocarbons were the main VOCs composition species in the two regions. The overall VOCs emission level of the Xigu Refining and Chemical Industrial Zone was higher than that of the downtown area, in which the concentration of halogenated hydrocarbons was 2.5 times higher than that of the central urban area, the concentration of olefins and aromatic hydrocarbon was more than 2 times higher, and the pollution level of alkynes was decreased. Overall, the trend of VOCs concentration changes in both areas was higher in winter and spring months, and lower in summer and autumn months. PMF source analysis results showed that vehicle exhaust gas source, oil and gas volatilization source, and organic solvents application source are the three main VOCs sources in the downtown area, while the industrial source was the most important VOCs source in Xigu Refining and Chemical Industrial Zone. Therefore, Lanzhou’s VOCs emission reduction control should be focused on reducing anthropogenic sources such as the petrochemical industry, motor vehicle exhaust, and solvent use.
2024, 42(4): 148-156.
doi: 10.13205/j.hjgc.202404018
Abstract:
To realize all-year-round air purification together with strengthening indoor ventilation in indoor environment, this study has numerically proposed a solar photocatalytic ventilation wall system coupling with hybrid ventilation and further investigated the diffusion characteristics of pollutants in winter and summer. Based on computational fluid dynamics, key parameters of solar radiation intensity and initial velocity have been comprehensively studied to analyze the effects on system pollutant removal rate and comprehensive evaluation index. The simulated results showed that the collaborative model for pollutant removal and hybrid ventilation is reliable and feasible. Especially, the comprehensive evaluation index for winter mode gradually increased from 0.00 to 1.00 with an increase in radiation intensity, while the summer model showed a negative correlation from 0.50 to 0.37. Increasing the initial velocity caused the comprehensive evaluation index of the winter model to decrease by up to 97%, while that of the summer model initially increased, then decreased and finally increased again. The adjustment of the external heat flow input and initial velocity has positive significance for promoting the removal of indoor pollutants.
To realize all-year-round air purification together with strengthening indoor ventilation in indoor environment, this study has numerically proposed a solar photocatalytic ventilation wall system coupling with hybrid ventilation and further investigated the diffusion characteristics of pollutants in winter and summer. Based on computational fluid dynamics, key parameters of solar radiation intensity and initial velocity have been comprehensively studied to analyze the effects on system pollutant removal rate and comprehensive evaluation index. The simulated results showed that the collaborative model for pollutant removal and hybrid ventilation is reliable and feasible. Especially, the comprehensive evaluation index for winter mode gradually increased from 0.00 to 1.00 with an increase in radiation intensity, while the summer model showed a negative correlation from 0.50 to 0.37. Increasing the initial velocity caused the comprehensive evaluation index of the winter model to decrease by up to 97%, while that of the summer model initially increased, then decreased and finally increased again. The adjustment of the external heat flow input and initial velocity has positive significance for promoting the removal of indoor pollutants.
2024, 42(4): 157-166.
doi: 10.13205/j.hjgc.202404019
Abstract:
In this study, Mn-TiO2/γ-Al2O3 catalyst was prepared by impregnation method to degrade xylene with dielectric barrier discharge (DBD) plasma. The oxidation properties of xylene in DBD plasma under different discharge power, initial mass concentration, and gas flow were studied. The catalyst was characterized by XRD and FT-IR to analyze the crystal shape and properties of the catalyst before and after DBD plasma discharge. The results showed that under the conditions of discharge power of 20 W, inlet concentration of xylene 38.62 mg/m3 and inlet flow rate of 0.65 L/min, the degradation efficiency of xylene reached 75.8% and the energy efficiency of the reactor was 0.1027 g/(kW·h) after adding Mn-TiO2/γ-Al2O3 catalyst. At the same time, ozone concentration was reduced to 36.94 mg/m3. The characterization results showed that the crystal shape and properties of the catalyst were not changed before and after the DBD plasma discharge. To further analyze the intermediate products produced in the process of degradation of xylene, FT-IR, GC-MS, and emission spectroscopy were used for diagnosis. It was found that the types and quantity of intermediate products decreased, the emission spectral intensity increased, and the number of characteristic spectral lines increased after adding catalyst. This study can provide a theoretical reference for the performance optimization and catalyst selection of DBD plasma in the application of xylene degradation.
In this study, Mn-TiO2/γ-Al2O3 catalyst was prepared by impregnation method to degrade xylene with dielectric barrier discharge (DBD) plasma. The oxidation properties of xylene in DBD plasma under different discharge power, initial mass concentration, and gas flow were studied. The catalyst was characterized by XRD and FT-IR to analyze the crystal shape and properties of the catalyst before and after DBD plasma discharge. The results showed that under the conditions of discharge power of 20 W, inlet concentration of xylene 38.62 mg/m3 and inlet flow rate of 0.65 L/min, the degradation efficiency of xylene reached 75.8% and the energy efficiency of the reactor was 0.1027 g/(kW·h) after adding Mn-TiO2/γ-Al2O3 catalyst. At the same time, ozone concentration was reduced to 36.94 mg/m3. The characterization results showed that the crystal shape and properties of the catalyst were not changed before and after the DBD plasma discharge. To further analyze the intermediate products produced in the process of degradation of xylene, FT-IR, GC-MS, and emission spectroscopy were used for diagnosis. It was found that the types and quantity of intermediate products decreased, the emission spectral intensity increased, and the number of characteristic spectral lines increased after adding catalyst. This study can provide a theoretical reference for the performance optimization and catalyst selection of DBD plasma in the application of xylene degradation.
2024, 42(4): 167-174.
doi: 10.13205/j.hjgc.202404020
Abstract:
Pulse back blow dedusting with conventional cartridge filters was found to be imbalanced in terms of energy allocation, with the lower and upper cartridge sections respectively getting excessive and insufficient energy apportionment, consequently causing not only the lower section to be more susceptible to damage, but also the upper section to be ineffective in dedusting. In light of this problem, the present study proposed fitting airflow-guiding columns within the filter cartridge to guide the reversely-blow airflow and improve the internal flow field. A series of numerical simulations and experimental tests were employed to determine how the cartridge fared in pulse jet cleaning. The results showed that the proposed column-fitted filter cartridge received more evenly-distributed reversely-blown pressure, as the impact pressure intensities at the middle and lower cartridge sections were reduced to 65% of that of the original cartridge, thereby rectifying the excessive blowing strength issue. At the same time, the proposed modification also generated a sharp impact pressure intensity peak at the upper cartridge section, which subsequently addressed the weak blowing strength issue. Furthermore, under unchanged working conditions, the proposed column-fitted filter cartridge also gained a service life that is 8 times longer than its conventional counterparts.
Pulse back blow dedusting with conventional cartridge filters was found to be imbalanced in terms of energy allocation, with the lower and upper cartridge sections respectively getting excessive and insufficient energy apportionment, consequently causing not only the lower section to be more susceptible to damage, but also the upper section to be ineffective in dedusting. In light of this problem, the present study proposed fitting airflow-guiding columns within the filter cartridge to guide the reversely-blow airflow and improve the internal flow field. A series of numerical simulations and experimental tests were employed to determine how the cartridge fared in pulse jet cleaning. The results showed that the proposed column-fitted filter cartridge received more evenly-distributed reversely-blown pressure, as the impact pressure intensities at the middle and lower cartridge sections were reduced to 65% of that of the original cartridge, thereby rectifying the excessive blowing strength issue. At the same time, the proposed modification also generated a sharp impact pressure intensity peak at the upper cartridge section, which subsequently addressed the weak blowing strength issue. Furthermore, under unchanged working conditions, the proposed column-fitted filter cartridge also gained a service life that is 8 times longer than its conventional counterparts.
2024, 42(4): 175-186.
doi: 10.13205/j.hjgc.202404021
Abstract:
Introducing exogenous additives into the anaerobic digestion system can improve the performance of the anaerobic digestion system and play a positive role in rapid start-up, reducing inhibition, improving fermentation efficiency, and improving process stability. In recent years, research on anaerobic digestion additives has developed rapidly. This paper reviews the research progress of eight kinds of anaerobic digestion additives (microorganisms, enzymes, trace elements, nanomaterials, adsorbents, conductive materials, ash, and gas). It focuses on discussing their effects and mechanisms in anaerobic digestion. This paper graphically presents the action modes of various additives in the anaerobic system, discusses the fundamental problems that need to be paid attention to in the use of additives, and points out the current research deficiencies and future research directions, aiming at providing essential references for the in-depth research and application of anaerobic digestion additives.
Introducing exogenous additives into the anaerobic digestion system can improve the performance of the anaerobic digestion system and play a positive role in rapid start-up, reducing inhibition, improving fermentation efficiency, and improving process stability. In recent years, research on anaerobic digestion additives has developed rapidly. This paper reviews the research progress of eight kinds of anaerobic digestion additives (microorganisms, enzymes, trace elements, nanomaterials, adsorbents, conductive materials, ash, and gas). It focuses on discussing their effects and mechanisms in anaerobic digestion. This paper graphically presents the action modes of various additives in the anaerobic system, discusses the fundamental problems that need to be paid attention to in the use of additives, and points out the current research deficiencies and future research directions, aiming at providing essential references for the in-depth research and application of anaerobic digestion additives.
2024, 42(4): 187-195.
doi: 10.13205/j.hjgc.202404022
Abstract:
It is an effective way to control surface subsidence, realize construction waste resources, reduce land occupation area to fill the coal goaf using construction waste. Uniaxial compression mechanics tests and surface hole fraction calculation were produced on 4 groups of 12 construction waste specimens with different cement content. The relationship between cement content and hole fraction was analyzed, the relationships of cement content and compressive strength, peak strain, and elastic modulus were discussed, failure instability modes of specimens were put forward, and the cement content range of filling specimens for peak strength, the strength reasonable range and rapid strength improvement were determined. The results showed that hole fraction and cement content had an antiphase relationship, cement content had a great influence on the stress-strain curve of filling specimens, the four-phase characteristics of the stress-strain curve was significant at cement content 15%, the greater cement content (the less hole fraction), the longer the elastic phase, conversely, the longer the yield phase. As cement content increased (hole fraction decreased), the strength and elastic modulus of filling specimens were increased according to cubic polynomial, and the axial strain showed decreasing, slow, trend to stable. The instability mode of filling specimens with less than 10% cement content was a multi-crack crushing failure, the one with 10% to 15% showed double back-arch shear failure, and the one with more than 15% showed double vertical splitting failure. The cement content range of the construction waste filling body was 7% to 20% according to mine requirements, the strength range 2.3647 to 15.7341 MPa, the peak strength of the filling specimen appeared at the cement content of 18.6991%, and the strength of filling specimens on the 28th day was 1.24 times on the 10th day.
It is an effective way to control surface subsidence, realize construction waste resources, reduce land occupation area to fill the coal goaf using construction waste. Uniaxial compression mechanics tests and surface hole fraction calculation were produced on 4 groups of 12 construction waste specimens with different cement content. The relationship between cement content and hole fraction was analyzed, the relationships of cement content and compressive strength, peak strain, and elastic modulus were discussed, failure instability modes of specimens were put forward, and the cement content range of filling specimens for peak strength, the strength reasonable range and rapid strength improvement were determined. The results showed that hole fraction and cement content had an antiphase relationship, cement content had a great influence on the stress-strain curve of filling specimens, the four-phase characteristics of the stress-strain curve was significant at cement content 15%, the greater cement content (the less hole fraction), the longer the elastic phase, conversely, the longer the yield phase. As cement content increased (hole fraction decreased), the strength and elastic modulus of filling specimens were increased according to cubic polynomial, and the axial strain showed decreasing, slow, trend to stable. The instability mode of filling specimens with less than 10% cement content was a multi-crack crushing failure, the one with 10% to 15% showed double back-arch shear failure, and the one with more than 15% showed double vertical splitting failure. The cement content range of the construction waste filling body was 7% to 20% according to mine requirements, the strength range 2.3647 to 15.7341 MPa, the peak strength of the filling specimen appeared at the cement content of 18.6991%, and the strength of filling specimens on the 28th day was 1.24 times on the 10th day.
2024, 42(4): 196-203.
doi: 10.13205/j.hjgc.202404023
Abstract:
Solid wastes such as slag, fly ash, steel slag, lime, and desulfurization ash were used to prepare a multi-solid waste activator (MSWA) for tailings filling. We constructed a multi-response optimization model, analyzed the significance of MSWA raw materials, and conducted microscopic experiments to explore the hydration mechanism. The above test results showed that: the error of the calculated value of the desired model of multiple responses was less than 2%, which can effectively reflect the proportioning willingness and the significance of raw materials; the TS-3 intention value of the test group was 0.812, and the 3-day strength and expansion were 0.643 MPa and 15.8 cm; the significant factors in 3-day strength term were cement clinker (0.629) and steel slag (0.171), the significant factor of expansion term was fly ash (0.761). The microscopic test showed that: in the OH- and SO2-4 solution provided by slag, C3S and C3A in cement clinker and other raw materials rapidly hydrated and released heat, and fly ash could promote hydration and improve the workability of mortar. In the product, C—S—H and AFt were well developed, making the structure compact, thus enhancing the macroscopic mechanical properties of the filling body.
Solid wastes such as slag, fly ash, steel slag, lime, and desulfurization ash were used to prepare a multi-solid waste activator (MSWA) for tailings filling. We constructed a multi-response optimization model, analyzed the significance of MSWA raw materials, and conducted microscopic experiments to explore the hydration mechanism. The above test results showed that: the error of the calculated value of the desired model of multiple responses was less than 2%, which can effectively reflect the proportioning willingness and the significance of raw materials; the TS-3 intention value of the test group was 0.812, and the 3-day strength and expansion were 0.643 MPa and 15.8 cm; the significant factors in 3-day strength term were cement clinker (0.629) and steel slag (0.171), the significant factor of expansion term was fly ash (0.761). The microscopic test showed that: in the OH- and SO2-4 solution provided by slag, C3S and C3A in cement clinker and other raw materials rapidly hydrated and released heat, and fly ash could promote hydration and improve the workability of mortar. In the product, C—S—H and AFt were well developed, making the structure compact, thus enhancing the macroscopic mechanical properties of the filling body.
2024, 42(4): 204-211.
doi: 10.13205/j.hjgc.202404024
Abstract:
The mechanism of the effect of hydrothermal treatment conditions on the degreasing properties and physical and chemical properties of food waste was investigated by varying the heating temperature (80, 100, 120, 140 ℃), heating time (50, 70, 90, 110 min) and centrifugal speed (3000, 5000, 7000, 9000 r/min). The results showed that the hydrothermal process was found to improve the oil extraction rate of food waste, which reached a maximum of 95.37% at a heating temperature of 120 ℃, a heating time of 90 minutes and a centrifugal speed of 9000 r/min; meanwhile, the hydrothermal process increased the concentration of SCOD and VFAs by up to 49.01% and 110.27% compared to the blank group, which promoted the hydrolysis of organic matter. In addition, the gas chromatography/mass spectrometry revealed that the hydrothermal process promoted the production of long-chain fatty acids, which increased by 77.18% to 149.14% compared with the blank group, improving the potential of kitchen grease as a biodiesel feedstock; the three-dimensional fluorescence spectroscopy analysis also showed that the transformation trend of dissolved organic matter after hydrothermal treatment was to degrade soluble microbial by-products into stable humic acid-like substances, which was conducive to the subsequent composting of food waste. It indicates that moderate hydrothermal treatment of food waste can effectively improve the oil extraction rate, organic matter hydrolysis capacity and bioavailable efficiency.
The mechanism of the effect of hydrothermal treatment conditions on the degreasing properties and physical and chemical properties of food waste was investigated by varying the heating temperature (80, 100, 120, 140 ℃), heating time (50, 70, 90, 110 min) and centrifugal speed (3000, 5000, 7000, 9000 r/min). The results showed that the hydrothermal process was found to improve the oil extraction rate of food waste, which reached a maximum of 95.37% at a heating temperature of 120 ℃, a heating time of 90 minutes and a centrifugal speed of 9000 r/min; meanwhile, the hydrothermal process increased the concentration of SCOD and VFAs by up to 49.01% and 110.27% compared to the blank group, which promoted the hydrolysis of organic matter. In addition, the gas chromatography/mass spectrometry revealed that the hydrothermal process promoted the production of long-chain fatty acids, which increased by 77.18% to 149.14% compared with the blank group, improving the potential of kitchen grease as a biodiesel feedstock; the three-dimensional fluorescence spectroscopy analysis also showed that the transformation trend of dissolved organic matter after hydrothermal treatment was to degrade soluble microbial by-products into stable humic acid-like substances, which was conducive to the subsequent composting of food waste. It indicates that moderate hydrothermal treatment of food waste can effectively improve the oil extraction rate, organic matter hydrolysis capacity and bioavailable efficiency.
2024, 42(4): 212-224.
doi: 10.13205/j.hjgc.202404025
Abstract:
The production of solid waste from non-ferrous metal mining and smelting is large, usually containing multiple heavy metals, which have both environmental risks and resource utilization value. This article established a solution for analyzing the environmental attributes and resource attributes of solid waste through an improved analytic hierarchy process (AHP) and the Topsis calculation method. Combined with the analysis of the composition and structural characteristics of 15 typical solid wastes, the solid waste attribute scores can be quantified, and their treatment paths can be guided. The results showed that the resource attributes of solid waste, such as mining waste and beneficiation tailings were stronger than environmental attributes, and the score of building materials utilization direction was greater than 0.5, indicating a bias towards building materials utilization; the environmental attribute of smelting solid waste, such as waste acid neutralizing slag was stronger than the resource attributes, indicating that its environmental pollution risk was high and must be treated harmlessly; smelting solid waste, such as goethite were rich in valuable metals such as Fe and Zn, and the economic and technological feasibility of metal extraction was high. The resource attributes were stronger than the environmental attributes, indicating its resource utilization approach for metal extraction. The established resource and environmental attributes analysis method can provide important guidance for the treatment and disposal of solid waste from non-ferrous mining, beneficiation, and metallurgy.
The production of solid waste from non-ferrous metal mining and smelting is large, usually containing multiple heavy metals, which have both environmental risks and resource utilization value. This article established a solution for analyzing the environmental attributes and resource attributes of solid waste through an improved analytic hierarchy process (AHP) and the Topsis calculation method. Combined with the analysis of the composition and structural characteristics of 15 typical solid wastes, the solid waste attribute scores can be quantified, and their treatment paths can be guided. The results showed that the resource attributes of solid waste, such as mining waste and beneficiation tailings were stronger than environmental attributes, and the score of building materials utilization direction was greater than 0.5, indicating a bias towards building materials utilization; the environmental attribute of smelting solid waste, such as waste acid neutralizing slag was stronger than the resource attributes, indicating that its environmental pollution risk was high and must be treated harmlessly; smelting solid waste, such as goethite were rich in valuable metals such as Fe and Zn, and the economic and technological feasibility of metal extraction was high. The resource attributes were stronger than the environmental attributes, indicating its resource utilization approach for metal extraction. The established resource and environmental attributes analysis method can provide important guidance for the treatment and disposal of solid waste from non-ferrous mining, beneficiation, and metallurgy.
2024, 42(4): 225-232.
doi: 10.13205/j.hjgc.202404026
Abstract:
The cement industry, as a key industry for greenhouse gas emissions, is under enormous pressure to reduce CO2 emissions. Limestone calcined clay cement developed in recent years is a highly promising low-carbon cement, and its raw materials, clay and limestone has a similar composition to excavated clay and recycled concrete fines in construction and demolition waste. Using the life cycle assessment (LCA) method as a basic framework, this paper evaluated the environmental and economic potential of a composite cement made of the abovementioned construction and demolition waste by creating an inventory analysis of the products. The results showed that the construction and demolition waste composite cement (C3) can reduce CO2 emissions by more than 24%, compared to the existing cement products, and production costs can be cut down by at least 19%. The future inclusion of the cement industry in the carbon emission trading market will further widen the cost gap between C3 and the existing cement products.
The cement industry, as a key industry for greenhouse gas emissions, is under enormous pressure to reduce CO2 emissions. Limestone calcined clay cement developed in recent years is a highly promising low-carbon cement, and its raw materials, clay and limestone has a similar composition to excavated clay and recycled concrete fines in construction and demolition waste. Using the life cycle assessment (LCA) method as a basic framework, this paper evaluated the environmental and economic potential of a composite cement made of the abovementioned construction and demolition waste by creating an inventory analysis of the products. The results showed that the construction and demolition waste composite cement (C3) can reduce CO2 emissions by more than 24%, compared to the existing cement products, and production costs can be cut down by at least 19%. The future inclusion of the cement industry in the carbon emission trading market will further widen the cost gap between C3 and the existing cement products.
2024, 42(4): 233-241.
doi: 10.13205/j.hjgc.202404027
Abstract:
Garbage siege has always been a big problem in China’s urban management. Aiming at the difficulties of the recyclable waste disposal process, this paper proposed a system based on the improved Inception ResNet V2 network combined with the ROBOT MG400 robotic arm for automatic sorting of recyclable waste. Firstly, we improved the fixture on the MG400 robotic arm to make it more suitable for garbage grabbing. Then, we independently created a dataset of 50850 sheets, based on which the garbage images were processed by background noise reduction, image classification, and voting algorithms, and the CBAM attention mechanism was added to the output layer of the Inception ResNet V2 network to improve the accuracy of model recognition. Finally, the whole system was experimentally verified. The verification results showed that the system could classify garbage more accurately and collect it into the corresponding garbage collection container, and the recognition accuracy was 99.35% and 95.39% when the conveyor belt was stationary and running, the mAP value of the improved network was 2.56% higher than that of the original model, and the sorting efficiency of the system reached 60 pieces per minute. Therefore, this system can independently complete the sorting of recyclable waste with high efficiency, high accuracy, and high precision.
Garbage siege has always been a big problem in China’s urban management. Aiming at the difficulties of the recyclable waste disposal process, this paper proposed a system based on the improved Inception ResNet V2 network combined with the ROBOT MG400 robotic arm for automatic sorting of recyclable waste. Firstly, we improved the fixture on the MG400 robotic arm to make it more suitable for garbage grabbing. Then, we independently created a dataset of 50850 sheets, based on which the garbage images were processed by background noise reduction, image classification, and voting algorithms, and the CBAM attention mechanism was added to the output layer of the Inception ResNet V2 network to improve the accuracy of model recognition. Finally, the whole system was experimentally verified. The verification results showed that the system could classify garbage more accurately and collect it into the corresponding garbage collection container, and the recognition accuracy was 99.35% and 95.39% when the conveyor belt was stationary and running, the mAP value of the improved network was 2.56% higher than that of the original model, and the sorting efficiency of the system reached 60 pieces per minute. Therefore, this system can independently complete the sorting of recyclable waste with high efficiency, high accuracy, and high precision.
2024, 42(4): 242-249.
doi: 10.13205/j.hjgc.202404028
Abstract:
The current research regarding the remediation of total petroleum hydrocarbon (TPH) contaminated soils largely ignores the effect of soil structures, and cannot provide either good temperature control or reasonable design of heating and extraction tubes. To address this issue, a new bench-scale thermal remediation apparatus has been developed to conduct thermal remediation tests of TPH-contaminated soils. The test results showed that the remediation effect of TPH(C6 to C9) was significantly affected by the heating temperature and heating time. The thermal remediation effect of contaminated soils showed large divergence at different locations within the insulation tank, and a good remediation effect is usually accomplished by shorter distances from the heating tube, extraction tube as well as soil surface; the influence from top cover system of the soil surface was however limited. It was also found that the particle components, pH value, contents of nitrogen, phosphorus and potassium of the contaminated soils showed small changes after thermal remediation, and the content of organic matter and moisture content had been significantly reduced. The novel apparatus developed in this study is expected to contribute to the improvement of in-situ thermal remediation technology of TPH-contaminated soils. The findings are supposed to be useful for the selection of operating parameters of thermal remediation technology in the prescribed field as well as environmental assessment.
The current research regarding the remediation of total petroleum hydrocarbon (TPH) contaminated soils largely ignores the effect of soil structures, and cannot provide either good temperature control or reasonable design of heating and extraction tubes. To address this issue, a new bench-scale thermal remediation apparatus has been developed to conduct thermal remediation tests of TPH-contaminated soils. The test results showed that the remediation effect of TPH(C6 to C9) was significantly affected by the heating temperature and heating time. The thermal remediation effect of contaminated soils showed large divergence at different locations within the insulation tank, and a good remediation effect is usually accomplished by shorter distances from the heating tube, extraction tube as well as soil surface; the influence from top cover system of the soil surface was however limited. It was also found that the particle components, pH value, contents of nitrogen, phosphorus and potassium of the contaminated soils showed small changes after thermal remediation, and the content of organic matter and moisture content had been significantly reduced. The novel apparatus developed in this study is expected to contribute to the improvement of in-situ thermal remediation technology of TPH-contaminated soils. The findings are supposed to be useful for the selection of operating parameters of thermal remediation technology in the prescribed field as well as environmental assessment.
2024, 42(4): 250-257.
doi: 10.13205/j.hjgc.202404029
Abstract:
To study the stress response of different plants under high-concentration doxycycline contamination and evaluate their remediation potentials for doxycycline contamination, 3 types of plants were selected for performing the germination and hydroponic experiments, including chicory, lettuce, and parsley. Based on it, the changes in seed germination, plant height, root length, and fresh weight were observed, and the contents of doxycycline in hydroponic nutrient solution over different periods of time were detected by high performance liquid chromatography. According to the results, it can be concluded that: 1) Doxycycline can promote the germination of chicory and lettuce seeds, but have an inhibitory effect on the germination of parsley seeds. The inhibitory effect of doxycycline on seed root length was significantly greater than shoot growth. 2) There were differences in the stress responses of three plants to doxycycline: the plant height, root length, and fresh weight of chicory and parsley had an obvious inhibitory effect on doxycycline; while doxycycline had no obvious inhibitory effect on the plant height and fresh weight of lettuce, it can promote the root growth of lettuce to a certain extent. 3) The removal rates for chicory, lettuce, and parsley to doxycycline in water were 81.75%, 58.42%, and 53.16% respectively. Chicory can be used as an alternative plant to degrade antibiotic contamination.
To study the stress response of different plants under high-concentration doxycycline contamination and evaluate their remediation potentials for doxycycline contamination, 3 types of plants were selected for performing the germination and hydroponic experiments, including chicory, lettuce, and parsley. Based on it, the changes in seed germination, plant height, root length, and fresh weight were observed, and the contents of doxycycline in hydroponic nutrient solution over different periods of time were detected by high performance liquid chromatography. According to the results, it can be concluded that: 1) Doxycycline can promote the germination of chicory and lettuce seeds, but have an inhibitory effect on the germination of parsley seeds. The inhibitory effect of doxycycline on seed root length was significantly greater than shoot growth. 2) There were differences in the stress responses of three plants to doxycycline: the plant height, root length, and fresh weight of chicory and parsley had an obvious inhibitory effect on doxycycline; while doxycycline had no obvious inhibitory effect on the plant height and fresh weight of lettuce, it can promote the root growth of lettuce to a certain extent. 3) The removal rates for chicory, lettuce, and parsley to doxycycline in water were 81.75%, 58.42%, and 53.16% respectively. Chicory can be used as an alternative plant to degrade antibiotic contamination.
2024, 42(4): 258-265.
doi: 10.13205/j.hjgc.202404030
Abstract:
The leakage of crude oil from oil tankers, drilling platforms, and oil wells causes oil pollutants to enter the sea and results in the deterioration of the marine ecological environment. In this paper, magnetic hydrophobic Ulva prolifera oil absorption materials were prepared by chemical modification method. The morphology, chemical composition, and wettability of Ulva prolifera at different modification stages were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and contact angle measurement. After modification with dopamine and dodecanethiol, the contact angle of water and oil of Ulva prolifera was about 131.4° and 0°, respectively, showing excellent hydrophobic and lipophilic properties. The maximum adsorption capacity of the modified Ulva prolifera for crude oil was 7.4 g/g, showing an excellent oil absorption capacity. Simulated oil-contaminated beach experiments illustrated that the adsorption rate of modified Ulva prolifera to the oil attached on the surface of coarse sand particles reached 78.4%, indicating that the hydrophobic magnetic Ulva prolifera has high value and potential in oil pollution control.
The leakage of crude oil from oil tankers, drilling platforms, and oil wells causes oil pollutants to enter the sea and results in the deterioration of the marine ecological environment. In this paper, magnetic hydrophobic Ulva prolifera oil absorption materials were prepared by chemical modification method. The morphology, chemical composition, and wettability of Ulva prolifera at different modification stages were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and contact angle measurement. After modification with dopamine and dodecanethiol, the contact angle of water and oil of Ulva prolifera was about 131.4° and 0°, respectively, showing excellent hydrophobic and lipophilic properties. The maximum adsorption capacity of the modified Ulva prolifera for crude oil was 7.4 g/g, showing an excellent oil absorption capacity. Simulated oil-contaminated beach experiments illustrated that the adsorption rate of modified Ulva prolifera to the oil attached on the surface of coarse sand particles reached 78.4%, indicating that the hydrophobic magnetic Ulva prolifera has high value and potential in oil pollution control.
2024, 42(4): 266-272.
doi: 10.13205/j.hjgc.202404031
Abstract:
In the context of the tidal river network area of the Pearl River Delta, drawing inspiration from the water quality management concept of total maximum daily load (TMDL) in the United States, a strategy for the environmental governance of the Nanshunliananwei Water System was proposed, with the primary objective of achieving water quality target. Taking ammonia nitrogen (NH3-N) as a representative indicator for the characterization of black and odorous water bodies, a simulation approach based on terrestrial pollution loads and water quality correlation models was employed. Following the conceptual framework of " pollutant loads calculation-environmental capacity assessment-pollutant loads allocation-engineering measures prediction", a refined NH3-N emission control scheme was developed scientifically. Through simulation calculation, the pollution load of NH3-N into the river can be reduced by 41.61 t/a through the source control and pollution interception projects. The water quality compliance rate in the river channels stands at 92.66%, marking a substantial increase of 35.92% compared to the conditions before the implementation of the engineering project.
In the context of the tidal river network area of the Pearl River Delta, drawing inspiration from the water quality management concept of total maximum daily load (TMDL) in the United States, a strategy for the environmental governance of the Nanshunliananwei Water System was proposed, with the primary objective of achieving water quality target. Taking ammonia nitrogen (NH3-N) as a representative indicator for the characterization of black and odorous water bodies, a simulation approach based on terrestrial pollution loads and water quality correlation models was employed. Following the conceptual framework of " pollutant loads calculation-environmental capacity assessment-pollutant loads allocation-engineering measures prediction", a refined NH3-N emission control scheme was developed scientifically. Through simulation calculation, the pollution load of NH3-N into the river can be reduced by 41.61 t/a through the source control and pollution interception projects. The water quality compliance rate in the river channels stands at 92.66%, marking a substantial increase of 35.92% compared to the conditions before the implementation of the engineering project.
2024, 42(4): 273-278.
doi: 10.13205/j.hjgc.202404032
Abstract:
To quickly investigate the overflow pollution pattern of urban rivers and to estimate the total pollution amount in complex urban areas, a calculation method based on monitoring data is proposed, which considers a closed region as a whole: Based on the balance relationship between domestic sewage volume, rainwater volume entering the sewage system, treated volume of the wastewater treatment plant, and overflow volume in the region, the overflow pollution is calculated by combining the monitoring data of pollutant concentration and flow, and further used to summarize the overflow pattern according to the rainfall data. The results show that based on 60 rainfall data, flow and water quality monitoring data during 458 days, the deviation between the calculated results and the monitoring results is +11.7%, and the accuracy of the results is acceptable. This method does not need to pay attention to the complex drainage network in the region, and the calculation and analysis is fast and reliable to support water environment planning and early stage of river water environment engineering.
To quickly investigate the overflow pollution pattern of urban rivers and to estimate the total pollution amount in complex urban areas, a calculation method based on monitoring data is proposed, which considers a closed region as a whole: Based on the balance relationship between domestic sewage volume, rainwater volume entering the sewage system, treated volume of the wastewater treatment plant, and overflow volume in the region, the overflow pollution is calculated by combining the monitoring data of pollutant concentration and flow, and further used to summarize the overflow pattern according to the rainfall data. The results show that based on 60 rainfall data, flow and water quality monitoring data during 458 days, the deviation between the calculated results and the monitoring results is +11.7%, and the accuracy of the results is acceptable. This method does not need to pay attention to the complex drainage network in the region, and the calculation and analysis is fast and reliable to support water environment planning and early stage of river water environment engineering.
