Login
Register
E-alert
Current Articles
2025, Volume 43, Issue 1
Display Method:
2025,
43(1):
1-11.
doi: 10.13205/j.hjgc.202501001
Abstract:
With the increasing scale and widespread utilization of chemicals, emerging contaminants such as persistent organic pollutants (POPs), endocrine-disrupting chemicals (EDCs), antibiotics, and microplastics have been detected extensively in aquatic environments, presenting significant and complex challenges to the safety of aquatic ecosystems and human health. This paper provides a systematic and detailed introduction to the concept, sources, and classifications of emerging contaminants, offering readers a comprehensive understanding of their nature. It also summarizes the harmful effects and the current control technologies available, while analyzing the core environmental ethical issues associated with these pollutants. Using bisphenol A (BPA) as a representative example, this study delved deeply into the environmental ethical dilemmas associated with the utilization, treatment, and disposal of such contaminants. Specifically, it examined issues concerning natural rights, environmental equity, and intergenerational justice, which are intricately linked to the broader governance and management of emerging contaminants. Moreover, the paper proposed actionable countermeasures and constructive recommendations aimed at tackling the ethical challenges associated with emerging pollutants in aquatic environments, emphasizing both theoretical insights and practical approaches. In the future, there is an urgent necessity to further enhance research and exploration into innovative control methods and comprehensive policy measures for emerging contaminants. This requires an integrated focus on both technological advancements and managerial innovations, ultimately providing robust theoretical support and practical solutions for strengthening ethical governance in water environmental protection. These efforts will contribute significantly to ensuring the sustainable safety and resilience of water resources in China.
With the increasing scale and widespread utilization of chemicals, emerging contaminants such as persistent organic pollutants (POPs), endocrine-disrupting chemicals (EDCs), antibiotics, and microplastics have been detected extensively in aquatic environments, presenting significant and complex challenges to the safety of aquatic ecosystems and human health. This paper provides a systematic and detailed introduction to the concept, sources, and classifications of emerging contaminants, offering readers a comprehensive understanding of their nature. It also summarizes the harmful effects and the current control technologies available, while analyzing the core environmental ethical issues associated with these pollutants. Using bisphenol A (BPA) as a representative example, this study delved deeply into the environmental ethical dilemmas associated with the utilization, treatment, and disposal of such contaminants. Specifically, it examined issues concerning natural rights, environmental equity, and intergenerational justice, which are intricately linked to the broader governance and management of emerging contaminants. Moreover, the paper proposed actionable countermeasures and constructive recommendations aimed at tackling the ethical challenges associated with emerging pollutants in aquatic environments, emphasizing both theoretical insights and practical approaches. In the future, there is an urgent necessity to further enhance research and exploration into innovative control methods and comprehensive policy measures for emerging contaminants. This requires an integrated focus on both technological advancements and managerial innovations, ultimately providing robust theoretical support and practical solutions for strengthening ethical governance in water environmental protection. These efforts will contribute significantly to ensuring the sustainable safety and resilience of water resources in China.
2025,
43(1):
12-20.
doi: 10.13205/j.hjgc.202501002
Abstract:
With the development of plastic pollution and the promotion of circular economy, the recycling of waste plastics has become an important issue in today’s world. The recycling of waste PET bottles to polyester filament can not only solve the problem of plastic pollution, but also contribute to the reduction of greenhouse gas emissions and the formation of circular economy. In this paper, a general carbon footprint and carbon emission reduction accounting method for filament recycled from waste PET bottles was established. The carbon footprint of recycled filament and carbon emission reduction compared with that of the virgin filament were quantitatively assessed based on actual production cases and localized databases. Furthermore, based on the technical investigation, the deep decarbonization measures of high-quality recycled filament were proposed and the deep decarbonization potential was estimated. The results showed that the carbon footprint of high-quality recycled filament was 1139 to 1779 kg CO2eq/t, 64% to 77% lower than that of the virgin filament. Power consumption is the main contributor to the product’s carbon footprint and the entry point for deep carbon reduction, which can be achieved through photovoltaic power generation replacement, heat recovery and electricity saving, etc. Substituting 16% of electricity from power grid with photovoltaic and simultaneously saving 16% of electricity consumption can reduce the carbon footprint by approximately 20%. The research results can provide methodology and localized data reference for carbon footprint accounting of recycled filament, offer concrete support for further decarbonization of recycled filament production, and promote the green and low-carbon transformation of China’s textile industry.
With the development of plastic pollution and the promotion of circular economy, the recycling of waste plastics has become an important issue in today’s world. The recycling of waste PET bottles to polyester filament can not only solve the problem of plastic pollution, but also contribute to the reduction of greenhouse gas emissions and the formation of circular economy. In this paper, a general carbon footprint and carbon emission reduction accounting method for filament recycled from waste PET bottles was established. The carbon footprint of recycled filament and carbon emission reduction compared with that of the virgin filament were quantitatively assessed based on actual production cases and localized databases. Furthermore, based on the technical investigation, the deep decarbonization measures of high-quality recycled filament were proposed and the deep decarbonization potential was estimated. The results showed that the carbon footprint of high-quality recycled filament was 1139 to 1779 kg CO2eq/t, 64% to 77% lower than that of the virgin filament. Power consumption is the main contributor to the product’s carbon footprint and the entry point for deep carbon reduction, which can be achieved through photovoltaic power generation replacement, heat recovery and electricity saving, etc. Substituting 16% of electricity from power grid with photovoltaic and simultaneously saving 16% of electricity consumption can reduce the carbon footprint by approximately 20%. The research results can provide methodology and localized data reference for carbon footprint accounting of recycled filament, offer concrete support for further decarbonization of recycled filament production, and promote the green and low-carbon transformation of China’s textile industry.
2025,
43(1):
21-30.
doi: 10.13205/j.hjgc.202501003
Abstract:
China is the world’s largest producer of primary aluminum. The carbon emissions from the production of primary aluminum account for about 5% of the total carbon emissions in society, which is of great significance to China’s "dual carbon" goal. To explore the sources of carbon emissions from primary aluminum production, a new algorithm for calculating carbon emissions from primary aluminum production was designed from the perspective of energy consumption. Three different grid emission factors, namely regional, baseline, and national, were selected to account for carbon emissions from primary aluminum production in China from 2012 to 2021, and to identify key factors that constrain primary aluminum production. The results showed that from 2012 to 2021, the carbon emissions from China’s primary aluminum production showed an overall upward trend, but the growth rate was slowing down, and the emission reduction effect of primary aluminum production was significant. Taking the baseline grid emission factor calculation as an example, 1) in 2012, the carbon emissions per ton of primary aluminum produced in China were 18.14 t/t. In 2021, the carbon emissions per ton of primary aluminum production in China were 12.48 t/t, with a decrease of 31.21%. 2) in terms of proportion, carbon emissions from primary aluminum production in China have always been dominated by electricity consumption. In 2021, nearly 90% of carbon emissions from primary aluminum production came from self-owned electricity and grid power consumption. 3) the four key factors that constrain the carbon emissions of primary aluminum production are the production of primary aluminum, the proportion of self-owned electricity, the comprehensive AC power consumption of primary aluminum, and the carbon dioxide emissions per unit of thermal power generation in China. In 2012, the carbon emissions per ton of aluminum in various regions of China were 15.67 t/t to 16.82 t/t, which decreased to 10.09 t/t to 11.09 t/t in 2021. The southern China has the lowest carbon emissions per ton of aluminum, with 10.09 tons of carbon emissions per ton of aluminum. Transferring the electrolytic aluminum industry to low-carbon emission factor areas, such as southern China, has a significant driving effect on emission reduction. At the same time, it is necessary to update the emission factors of China’s regional power grid as soon as possible, to accurately reflect the energy consumption structure of each region, and provide a basis for formulating relevant policies to guide the emission reduction of primary aluminum production.
China is the world’s largest producer of primary aluminum. The carbon emissions from the production of primary aluminum account for about 5% of the total carbon emissions in society, which is of great significance to China’s "dual carbon" goal. To explore the sources of carbon emissions from primary aluminum production, a new algorithm for calculating carbon emissions from primary aluminum production was designed from the perspective of energy consumption. Three different grid emission factors, namely regional, baseline, and national, were selected to account for carbon emissions from primary aluminum production in China from 2012 to 2021, and to identify key factors that constrain primary aluminum production. The results showed that from 2012 to 2021, the carbon emissions from China’s primary aluminum production showed an overall upward trend, but the growth rate was slowing down, and the emission reduction effect of primary aluminum production was significant. Taking the baseline grid emission factor calculation as an example, 1) in 2012, the carbon emissions per ton of primary aluminum produced in China were 18.14 t/t. In 2021, the carbon emissions per ton of primary aluminum production in China were 12.48 t/t, with a decrease of 31.21%. 2) in terms of proportion, carbon emissions from primary aluminum production in China have always been dominated by electricity consumption. In 2021, nearly 90% of carbon emissions from primary aluminum production came from self-owned electricity and grid power consumption. 3) the four key factors that constrain the carbon emissions of primary aluminum production are the production of primary aluminum, the proportion of self-owned electricity, the comprehensive AC power consumption of primary aluminum, and the carbon dioxide emissions per unit of thermal power generation in China. In 2012, the carbon emissions per ton of aluminum in various regions of China were 15.67 t/t to 16.82 t/t, which decreased to 10.09 t/t to 11.09 t/t in 2021. The southern China has the lowest carbon emissions per ton of aluminum, with 10.09 tons of carbon emissions per ton of aluminum. Transferring the electrolytic aluminum industry to low-carbon emission factor areas, such as southern China, has a significant driving effect on emission reduction. At the same time, it is necessary to update the emission factors of China’s regional power grid as soon as possible, to accurately reflect the energy consumption structure of each region, and provide a basis for formulating relevant policies to guide the emission reduction of primary aluminum production.
Research progress on accounting, modeling and influencing factors of transportation carbon emissions
2025,
43(1):
31-41.
doi: 10.13205/j.hjgc.202501004
Abstract:
Amidst the backdrop of accelerated urbanization and the sustained development of infrastructure, carbon emissions from the transportation sector have emerged as a critical impediment to the sustainable development of the global community. This paper presents a systematic review of the principal scholarly achievements in transportation carbon emissions from 2019 to 2024, providing an in-depth analysis of research progress, current challenges, and developmental trends at both the macro level and within the road transport domain. The results indicate a significant upward trend in research on transportation carbon emissions, focusing on carbon emission inventory accounting, simulation studies, influencing factors, and policy assessments as the primary research entry points. The predominant estimation method is the "top-down" approach, with a clear trend toward integrating multiple models and innovation in research models. Socioeconomic indicators are identified as core considerations that significantly impact transportation carbon emissions, with the optimization of transportation structures and technological innovation recognized as effective strategies for reducing carbon emissions. Policy guidance is shown to be effective in lowering carbon emissions, with a focus on strengthening urban transportation construction management and promoting the establishment and improvement of carbon emission trading markets as the main directions for policy formulation. Future research on transportation carbon emissions should further concentrate on the characteristics of carbon emissions within the context of urbanization, the application of visualization and dynamic simulation technologies, and deepen the comprehensive analysis of diverse and holistic influencing factors. This will provide theoretical support and practical guidance for the implementation of precise and efficient strategies for reducing transportation carbon emissions. The integration of socioeconomic indicators into transportation planning and policy is crucial for achieving sustainable outcomes, and the study emphasizes the need for a shift towards more sustainable transportation structures and the adoption of innovative technologies that can significantly reduce the carbon footprint of the sector. Policymakers are urged to consider these findings when formulating strategies aimed at reducing carbon emissions, particularly in the context of urban development and the establishment of carbon trading markets. By integrating research findings into policy and practice, the research community and policymakers can work together to develop and implement strategies. It is also essential to foster international cooperation and knowledge exchange to address the global challenge of transportation carbon emissions effectively.
Amidst the backdrop of accelerated urbanization and the sustained development of infrastructure, carbon emissions from the transportation sector have emerged as a critical impediment to the sustainable development of the global community. This paper presents a systematic review of the principal scholarly achievements in transportation carbon emissions from 2019 to 2024, providing an in-depth analysis of research progress, current challenges, and developmental trends at both the macro level and within the road transport domain. The results indicate a significant upward trend in research on transportation carbon emissions, focusing on carbon emission inventory accounting, simulation studies, influencing factors, and policy assessments as the primary research entry points. The predominant estimation method is the "top-down" approach, with a clear trend toward integrating multiple models and innovation in research models. Socioeconomic indicators are identified as core considerations that significantly impact transportation carbon emissions, with the optimization of transportation structures and technological innovation recognized as effective strategies for reducing carbon emissions. Policy guidance is shown to be effective in lowering carbon emissions, with a focus on strengthening urban transportation construction management and promoting the establishment and improvement of carbon emission trading markets as the main directions for policy formulation. Future research on transportation carbon emissions should further concentrate on the characteristics of carbon emissions within the context of urbanization, the application of visualization and dynamic simulation technologies, and deepen the comprehensive analysis of diverse and holistic influencing factors. This will provide theoretical support and practical guidance for the implementation of precise and efficient strategies for reducing transportation carbon emissions. The integration of socioeconomic indicators into transportation planning and policy is crucial for achieving sustainable outcomes, and the study emphasizes the need for a shift towards more sustainable transportation structures and the adoption of innovative technologies that can significantly reduce the carbon footprint of the sector. Policymakers are urged to consider these findings when formulating strategies aimed at reducing carbon emissions, particularly in the context of urban development and the establishment of carbon trading markets. By integrating research findings into policy and practice, the research community and policymakers can work together to develop and implement strategies. It is also essential to foster international cooperation and knowledge exchange to address the global challenge of transportation carbon emissions effectively.
2025,
43(1):
42-50.
doi: 10.13205/j.hjgc.202501005
Abstract:
A substantial quantity of waste, including engineering residue, drilling residue, and mud cake, is inevitably generated during railway construction in China. Improper disposal of this waste not only consumes significant land resources but also poses severe environmental pollution risks. This study focuses on the drilling slag, slag, and mud cake produced during railway construction. Firstly, we analyzed the resource and environmental properties of these wastes, such as heavy metal content and mineral composition. Based on this analysis, different proportions of construction waste and ceramisite raw materials were mixed, and recycled ceramisite was prepared using a sintering method. By measuring physical properties including apparent density and bulk density, we examined the effect of varying waste ratio on the characteristics of recycled ceramics. Additionally, we investigated the leaching behavior of regenerated ceramics and evaluated the concentrations of heavy metals through leaching toxicity test to assess the potential ecological pollution risk. The results demonstrated that: 1) significant differences existed in heavy metal concentration and mineral composition among different types of construction waste, providing a basis for waste classification and resource utilization. 2) the physical properties of recycled ceramics, such as apparent density and bulk density, varied depending on the amount of construction waste, necessitating controlled waste ratios based on specific application requirements. 3) compared to the raw materials, the concentrations of heavy metals in reclaimed ceramics was increased, posing an ecological pollution risk that requires appropriate controlling measures.
A substantial quantity of waste, including engineering residue, drilling residue, and mud cake, is inevitably generated during railway construction in China. Improper disposal of this waste not only consumes significant land resources but also poses severe environmental pollution risks. This study focuses on the drilling slag, slag, and mud cake produced during railway construction. Firstly, we analyzed the resource and environmental properties of these wastes, such as heavy metal content and mineral composition. Based on this analysis, different proportions of construction waste and ceramisite raw materials were mixed, and recycled ceramisite was prepared using a sintering method. By measuring physical properties including apparent density and bulk density, we examined the effect of varying waste ratio on the characteristics of recycled ceramics. Additionally, we investigated the leaching behavior of regenerated ceramics and evaluated the concentrations of heavy metals through leaching toxicity test to assess the potential ecological pollution risk. The results demonstrated that: 1) significant differences existed in heavy metal concentration and mineral composition among different types of construction waste, providing a basis for waste classification and resource utilization. 2) the physical properties of recycled ceramics, such as apparent density and bulk density, varied depending on the amount of construction waste, necessitating controlled waste ratios based on specific application requirements. 3) compared to the raw materials, the concentrations of heavy metals in reclaimed ceramics was increased, posing an ecological pollution risk that requires appropriate controlling measures.
2025,
43(1):
51-61.
doi: 10.13205/j.hjgc.202501006
Abstract:
Within the framework of the new development plan to address the issue of global climate change, the treatment and disposal of solid waste will be guided by innovative concepts such as carbon recycling and energy regeneration. The construction and development of venous industrial parks are of great importance for achieving China’s national "Dual-Carbon" goal. Carbon emission reduction and resource recycling are both taken into consideration, in the development mode of integrated waste treatment in venous industrial parks. The scientific assessment of carbon emissions reduction efficacy in venous industrial parks could explore its developmental direction and furnish empirical evidence for governmental energy conservation and emission reduction policy formulation. Based on CDM methodology, presence and absence comparison method, emission factor method, this study selected a typical integrated venous industrial park with a domestic waste incineration plant as the core, and estimated and analyzed the carbon emission reduction of major projects, such as waste incineration cogeneration, construction waste recycling, and food and kitchen waste treatment in the park. The treatment capacity of various waste treated in the park is 1.407 million tons per year. The annual carbon emission reduction of the main project is 804,716 tons of CO2e. This study assessed the carbon emission reduction potential of the venous industrial parks, serving as a reference for its participation in carbon sink trading and the achievement of synergistic economic and environment.
Within the framework of the new development plan to address the issue of global climate change, the treatment and disposal of solid waste will be guided by innovative concepts such as carbon recycling and energy regeneration. The construction and development of venous industrial parks are of great importance for achieving China’s national "Dual-Carbon" goal. Carbon emission reduction and resource recycling are both taken into consideration, in the development mode of integrated waste treatment in venous industrial parks. The scientific assessment of carbon emissions reduction efficacy in venous industrial parks could explore its developmental direction and furnish empirical evidence for governmental energy conservation and emission reduction policy formulation. Based on CDM methodology, presence and absence comparison method, emission factor method, this study selected a typical integrated venous industrial park with a domestic waste incineration plant as the core, and estimated and analyzed the carbon emission reduction of major projects, such as waste incineration cogeneration, construction waste recycling, and food and kitchen waste treatment in the park. The treatment capacity of various waste treated in the park is 1.407 million tons per year. The annual carbon emission reduction of the main project is 804,716 tons of CO2e. This study assessed the carbon emission reduction potential of the venous industrial parks, serving as a reference for its participation in carbon sink trading and the achievement of synergistic economic and environment.
2025,
43(1):
62-69.
doi: 10.13205/j.hjgc.202501007
Abstract:
Ti4O7, due to its high electrochemical stability and electronic conductivity, has been widely used in electrochemistry and has shown excellent performance. In this paper, a high-performance carbon modified Ti4O7 electrode membrane prepared by extraction and filtration method was used in a flow-through filtration system to achieve efficient phenol degradation. SEM, XPS, and XRD were used to characterize the morphology and crystal structure of carbon materials with different loading ratios and structures. The effects of different catalysts and carbon material loading, applied voltage, solution pH, and flow rate on the degradation efficiency of phenol were investigated. The results showed that the oxidation flux of the electrode film in the circulation system reached 1208.5 mg/(h·m2), when the addition of acetylene carbon black (ATCE) was 5%, the voltage was 4 V, the solution pH was 3.0, and the flow rate was 1.5 mL/min. Comparing the electrochemical performance test results before and after the loading of carbon material, it was found that the presence of carbon material between the Ti4O7 crystals significantly improved the electron transfer rate. This paper further confirms the electrode surface properties and the relationship between the anode electric catalytic oxidation performance, and provides a new path for the electrode reactor optimization
Ti4O7, due to its high electrochemical stability and electronic conductivity, has been widely used in electrochemistry and has shown excellent performance. In this paper, a high-performance carbon modified Ti4O7 electrode membrane prepared by extraction and filtration method was used in a flow-through filtration system to achieve efficient phenol degradation. SEM, XPS, and XRD were used to characterize the morphology and crystal structure of carbon materials with different loading ratios and structures. The effects of different catalysts and carbon material loading, applied voltage, solution pH, and flow rate on the degradation efficiency of phenol were investigated. The results showed that the oxidation flux of the electrode film in the circulation system reached 1208.5 mg/(h·m2), when the addition of acetylene carbon black (ATCE) was 5%, the voltage was 4 V, the solution pH was 3.0, and the flow rate was 1.5 mL/min. Comparing the electrochemical performance test results before and after the loading of carbon material, it was found that the presence of carbon material between the Ti4O7 crystals significantly improved the electron transfer rate. This paper further confirms the electrode surface properties and the relationship between the anode electric catalytic oxidation performance, and provides a new path for the electrode reactor optimization
2025,
43(1):
70-79.
doi: 10.13205/j.hjgc.202501008
Abstract:
Based on the Dual Carbon background, this article analyzes the current status of carbon capture technology research in wastewater treatment and selects a total of 2654 relevant documents from the Web of Science. Through a comprehensive analysis of the year of publication, organization, author, and keyword map of the papers, it is concluded that there are three key frontiers in the current development of carbon capture technology in wastewater treatment. First of all, the selection and optimization of the carbon capture process is a major research field with great concern. This involves augmenting existing greenhouse gas mitigation technologies and fostering the development of novel, transformative low-carbon technologies. Secondly, the research on carbon capture products and the ways and extent of resource and energy utilization are also crucial research perspectives. Lastly, some studies are concerned with conducting dynamic life cycle assessment of the water environment under the framework of carbon neutrality, and the establishment of calculation models to estimate the carbon footprint and energy consumption potential of wastewater treatment plants, to inform sustainable development strategies. Future research directions will likely focus on the expansion and enhancement of mathematical modeling and non-technical analysis (such as socio-economic and environmental fundamentals) to provide a more nuanced understanding of the economic benefits and sustainability of carbon capture technologies. The research presented in this article employs CiteSpace software to conduct a rigorous and visual analysis of the existing research on carbon capture technologies in wastewater treatment, to provide a integrated understanding of the current state of knowledge in the field, and to identify potential challenges and opportunities for future development and innovation, thereby informing strategies for sustainable development and advancement in wastewater treatment industry.
Based on the Dual Carbon background, this article analyzes the current status of carbon capture technology research in wastewater treatment and selects a total of 2654 relevant documents from the Web of Science. Through a comprehensive analysis of the year of publication, organization, author, and keyword map of the papers, it is concluded that there are three key frontiers in the current development of carbon capture technology in wastewater treatment. First of all, the selection and optimization of the carbon capture process is a major research field with great concern. This involves augmenting existing greenhouse gas mitigation technologies and fostering the development of novel, transformative low-carbon technologies. Secondly, the research on carbon capture products and the ways and extent of resource and energy utilization are also crucial research perspectives. Lastly, some studies are concerned with conducting dynamic life cycle assessment of the water environment under the framework of carbon neutrality, and the establishment of calculation models to estimate the carbon footprint and energy consumption potential of wastewater treatment plants, to inform sustainable development strategies. Future research directions will likely focus on the expansion and enhancement of mathematical modeling and non-technical analysis (such as socio-economic and environmental fundamentals) to provide a more nuanced understanding of the economic benefits and sustainability of carbon capture technologies. The research presented in this article employs CiteSpace software to conduct a rigorous and visual analysis of the existing research on carbon capture technologies in wastewater treatment, to provide a integrated understanding of the current state of knowledge in the field, and to identify potential challenges and opportunities for future development and innovation, thereby informing strategies for sustainable development and advancement in wastewater treatment industry.
2025,
43(1):
80-88.
doi: 10.13205/j.hjgc.202501009
Abstract:
The paper industry generates a large amount of wastewater and sludge containing organic pollutants and heavy metals during its production process, leading to serious soil environmental pollution in the paper mill and its surrounding areas, which makes the soil remediation project for the paper mills and their surrounding areas more difficult. Consequently, there is an urgent need for environmental impact assessment to minimize the ecological footprint of the remediation process. Taking a contaminated site in a paper mill as an example, this study applied a life cycle assessment (LCA) approach to analyze the environmental footprint of soil remediation efforts, aiming to explore a sustainable and environmentally friendly method for soil restoration. In this study, the SEFA (sustainable environmental footprint assessment) tool was used to calculate the environmental footprints of three alternative remediation scenarios: 1) ex-situ chemical oxidation combined with cement kiln co-processing (Scenario 1), 2) cement kiln co-processing alone (Scenario 2), and 3) ex-situ thermal desorption combined with soil washing (Scenario 3). The SEFA tool is developed by the US Environmental Protection Agency, covering five core elements of GSR, and quantifying energy consumption and carbon footprint generated by remediation of contaminated sites. The results showed that regarding material consumption, total energy consumption, greenhouse gas emissions, and air pollutant emissions, the environmental impacts followed the order of Scenario 3 < Scenario 2 < Scenario 1. The carbon emissions from each remediation technique ranged from 0.05 to 0.66 t CO2 e/m3. Additionally, Monte Carlo uncertainty analysis confirmed the robustness and reliability of the simulation results. Under the national background of the Dual-Carbon policy, China’s paper industry is constantly optimizing its industrial layout and building a low-carbon development cluster. These findings suggest that the SEFA tool is highly applicable for evaluating soil remediation options in the paper industry. It provides a framework for assessing both the environmental impact and the feasibility of different remediation strategies, demonstrating potential advantages for complex sites contaminated with organic pollutants and heavy metals. This paper can serve as a scientific foundation for decision-making and contribute to improving the environmental performance of soil remediation in the paper industry, helping to guide future efforts to address pollution in the sector.
The paper industry generates a large amount of wastewater and sludge containing organic pollutants and heavy metals during its production process, leading to serious soil environmental pollution in the paper mill and its surrounding areas, which makes the soil remediation project for the paper mills and their surrounding areas more difficult. Consequently, there is an urgent need for environmental impact assessment to minimize the ecological footprint of the remediation process. Taking a contaminated site in a paper mill as an example, this study applied a life cycle assessment (LCA) approach to analyze the environmental footprint of soil remediation efforts, aiming to explore a sustainable and environmentally friendly method for soil restoration. In this study, the SEFA (sustainable environmental footprint assessment) tool was used to calculate the environmental footprints of three alternative remediation scenarios: 1) ex-situ chemical oxidation combined with cement kiln co-processing (Scenario 1), 2) cement kiln co-processing alone (Scenario 2), and 3) ex-situ thermal desorption combined with soil washing (Scenario 3). The SEFA tool is developed by the US Environmental Protection Agency, covering five core elements of GSR, and quantifying energy consumption and carbon footprint generated by remediation of contaminated sites. The results showed that regarding material consumption, total energy consumption, greenhouse gas emissions, and air pollutant emissions, the environmental impacts followed the order of Scenario 3 < Scenario 2 < Scenario 1. The carbon emissions from each remediation technique ranged from 0.05 to 0.66 t CO2 e/m3. Additionally, Monte Carlo uncertainty analysis confirmed the robustness and reliability of the simulation results. Under the national background of the Dual-Carbon policy, China’s paper industry is constantly optimizing its industrial layout and building a low-carbon development cluster. These findings suggest that the SEFA tool is highly applicable for evaluating soil remediation options in the paper industry. It provides a framework for assessing both the environmental impact and the feasibility of different remediation strategies, demonstrating potential advantages for complex sites contaminated with organic pollutants and heavy metals. This paper can serve as a scientific foundation for decision-making and contribute to improving the environmental performance of soil remediation in the paper industry, helping to guide future efforts to address pollution in the sector.
2025,
43(1):
89-96.
doi: 10.13205/j.hjgc.202501010
Abstract:
The safe operation and maintenance of urban drainage networks, especially the proper disposal of sewer sediment, has become an urgent challenge as urbanization accelerates and wastewater treatment processes generate increasing amounts of sediment. In response, the Technical Regulations for the Treatment and Disposal of Sewer Sludge in Urban Drainage Systems, released in 2022, mandates that the organic component of sewer sediment must be reduced to 5% below, before it can be safely landfilled or reused as building materials. This requirement depends on the effective separation of organic and inorganic sewer sediment components, a complex process that has not been deeply studied. Traditional treatment methods, such as multi-stage hydraulic panning, rely on hydraulic forces and material concentration differences to separate the components. However, the methods are inefficient and consume numerous water resources. In contrast, newer technologies, alkaline hydrolysis, thermal hydrolysis, and CER (cation exchange resin), offer promising solutions to improve the separation efficiency. These methods aim to break down biopolymers directly or disrupt ion bridges through CER, thereby promoting the decomposition of sediment. Direct cracking methods focus on the breaking of biopolymers. While indirect approaches, CER, focus on breaking down the bonds that hold the components together. Although the number of research on CER treatment remains limited, it offers a more sustainable solution than traditional methods. This review explored the composition and environmental hazards of sewer sediment, emphasizing the importance of effective separation of organic and inorganic components. The current status of traditional hydraulic panning, typical hydrolysis methods, and CER technology were studied. By comparing the efficiency and mechanisms of those methods, the review evaluated the advantages and disadvantages from the perspective of engineering implementation, environmental impact, and economic benefits. The findings suggested that CER treatment, with high separation efficiency and sustainability, holds great potential in future sewer sediment management. Overall, this review provides both theoretical insights and practical guidance for advancing the understanding of organic/inorganic component separation in sewer sediment and encourages the development of efficient treatment technologies. A new recycling method of CER is also proposed to increase the economic and environmental benefits of sediment treatment.
The safe operation and maintenance of urban drainage networks, especially the proper disposal of sewer sediment, has become an urgent challenge as urbanization accelerates and wastewater treatment processes generate increasing amounts of sediment. In response, the Technical Regulations for the Treatment and Disposal of Sewer Sludge in Urban Drainage Systems, released in 2022, mandates that the organic component of sewer sediment must be reduced to 5% below, before it can be safely landfilled or reused as building materials. This requirement depends on the effective separation of organic and inorganic sewer sediment components, a complex process that has not been deeply studied. Traditional treatment methods, such as multi-stage hydraulic panning, rely on hydraulic forces and material concentration differences to separate the components. However, the methods are inefficient and consume numerous water resources. In contrast, newer technologies, alkaline hydrolysis, thermal hydrolysis, and CER (cation exchange resin), offer promising solutions to improve the separation efficiency. These methods aim to break down biopolymers directly or disrupt ion bridges through CER, thereby promoting the decomposition of sediment. Direct cracking methods focus on the breaking of biopolymers. While indirect approaches, CER, focus on breaking down the bonds that hold the components together. Although the number of research on CER treatment remains limited, it offers a more sustainable solution than traditional methods. This review explored the composition and environmental hazards of sewer sediment, emphasizing the importance of effective separation of organic and inorganic components. The current status of traditional hydraulic panning, typical hydrolysis methods, and CER technology were studied. By comparing the efficiency and mechanisms of those methods, the review evaluated the advantages and disadvantages from the perspective of engineering implementation, environmental impact, and economic benefits. The findings suggested that CER treatment, with high separation efficiency and sustainability, holds great potential in future sewer sediment management. Overall, this review provides both theoretical insights and practical guidance for advancing the understanding of organic/inorganic component separation in sewer sediment and encourages the development of efficient treatment technologies. A new recycling method of CER is also proposed to increase the economic and environmental benefits of sediment treatment.
2025,
43(1):
97-106.
doi: 10.13205/j.hjgc.202501011
Abstract:
In addressing the challenge of low nitrogen removal efficiency in wastewater treatment plants under low-temperature conditions, this study undertook a comprehensive comparison of pollutant removal efficiency, sludge extracellular polymeric substances (EPS), and microbial community structure. This comparison focused on two treatment systems: the high-concentration composite powder bio-fluidized (HPB) system and the anaerobic-anoxic-oxic (AAO) process. The basis for this comparison was rooted in the detailed physical and chemical characterization of the PY@DE composite powder carrier materials utilized within the HPB system. The results of this investigation unequivocally indicated that the incorporation of the PY@DE composite powder carrier into the HPB system significantly enhanced its overall performance metrics. Specifically, the average total nitrogen (TN) concentration reached 6.85 mg/L, a level considerably lower than the Class A Discharge Standard stipulated in the Pollutant Discharge Standard for Urban Sewage Treatment Plants (GB 18918—2002). Moreover, the HPB system demonstrated an average TN removal rate of an impressive 89%, which represents a substantial improvement over the performance of the AAO process by a notable margin of 14%. Key factors contributing to the superior performance of the HPB system include the exceptional properties of the PY@DE composite powder carrier. This carrier exhibited a contact angle of 14.6°, which is indicative of its favorable wettability, coupled with an interfacial adsorption free energy of 46.28 mJ/m2. These properties are essential for enhancing interaction with wastewater constituents, thereby facilitating efficient adsorption and subsequent removal of nitrogenous compounds. Furthermore, the introduction of the composite powder carrier positively influenced the microbial community structure within the HPB system. It selectively enriched populations of nitrogen-removing bacteria, notably Dokdonella, Rhodobacter, and Hydrogenophaga, which are crucial for effective nitrogen degradation. These findings collectively suggest that the PY@DE composite powder carrier not only possesses excellent biocompatibility, which is instrumental in fostering the growth of beneficial microorganisms, but also enhances biofilm stability. This stability is particularly vital for maintaining high nitrogen removal efficiency, especially under challenging low-temperature conditions that typically hinder microbial activity. Ultimately, the insights derived from this study advocate for the integration of advanced bio-carrier materials, such as the PY@DE composite, into wastewater treatment methodologies to significantly improve nitrogen removal efficiencies.
In addressing the challenge of low nitrogen removal efficiency in wastewater treatment plants under low-temperature conditions, this study undertook a comprehensive comparison of pollutant removal efficiency, sludge extracellular polymeric substances (EPS), and microbial community structure. This comparison focused on two treatment systems: the high-concentration composite powder bio-fluidized (HPB) system and the anaerobic-anoxic-oxic (AAO) process. The basis for this comparison was rooted in the detailed physical and chemical characterization of the PY@DE composite powder carrier materials utilized within the HPB system. The results of this investigation unequivocally indicated that the incorporation of the PY@DE composite powder carrier into the HPB system significantly enhanced its overall performance metrics. Specifically, the average total nitrogen (TN) concentration reached 6.85 mg/L, a level considerably lower than the Class A Discharge Standard stipulated in the Pollutant Discharge Standard for Urban Sewage Treatment Plants (GB 18918—2002). Moreover, the HPB system demonstrated an average TN removal rate of an impressive 89%, which represents a substantial improvement over the performance of the AAO process by a notable margin of 14%. Key factors contributing to the superior performance of the HPB system include the exceptional properties of the PY@DE composite powder carrier. This carrier exhibited a contact angle of 14.6°, which is indicative of its favorable wettability, coupled with an interfacial adsorption free energy of 46.28 mJ/m2. These properties are essential for enhancing interaction with wastewater constituents, thereby facilitating efficient adsorption and subsequent removal of nitrogenous compounds. Furthermore, the introduction of the composite powder carrier positively influenced the microbial community structure within the HPB system. It selectively enriched populations of nitrogen-removing bacteria, notably Dokdonella, Rhodobacter, and Hydrogenophaga, which are crucial for effective nitrogen degradation. These findings collectively suggest that the PY@DE composite powder carrier not only possesses excellent biocompatibility, which is instrumental in fostering the growth of beneficial microorganisms, but also enhances biofilm stability. This stability is particularly vital for maintaining high nitrogen removal efficiency, especially under challenging low-temperature conditions that typically hinder microbial activity. Ultimately, the insights derived from this study advocate for the integration of advanced bio-carrier materials, such as the PY@DE composite, into wastewater treatment methodologies to significantly improve nitrogen removal efficiencies.
2025,
43(1):
107-117.
doi: 10.13205/j.hjgc.202501012
Abstract:
In the context of addressing the ever-increasing issue of phosphorus pollution in water bodies, the adsorption method has emerged as a promising approach. However, for an adsorbent to be truly viable in practical applications, its adsorption performance and recyclability play pivotal roles. These two aspects determine whether it can effectively remove phosphorus from water over an extended period and be reused economically and eco-friendly. Through a relatively straightforward yet effective impregnation-calcination technique, a novel magnesium-modified fibrous phosphate adsorbent, denoted as MgO@CFF, was successfully fabricated. This adsorbent was designed to possess both remarkable adsorption performance and satisfactory recyclability, aiming to overcome the limitations of many existing adsorbents in dealing with phosphorus-contaminated water. Subsequently, a series of comprehensive experiments were carried out with the MgO@CFF as the focus. Specifically, its performance was meticulously evaluated under diverse conditions that mimic real-world water environments, including different initial phosphorus concentrations, the presence of various coexisting ions, and a wide range of pH values. The obtained experimental results are quite significant. Firstly, within a broad pH interval spanning from 3 to 7, the maximum adsorption capacity of MgO@CFF can reach an impressive value of 11.23 mg-P/g. This indicates its robustness in handling phosphorus under a relatively wide range of acidity and alkalinity conditions that are common in natural and industrial water systems. Secondly, even when confronted with different types of foreign anions in the water, MgO@CFF still showcases its outstanding ability to selectively adsorb phosphate, with a preferential selectivity exceeding 50%. Furthermore, in terms of the adsorption kinetics, MgO@CFF exhibits a remarkable characteristic of rapid adsorption. At the 60-minute mark during the adsorption process, the amount of phosphorus adsorbed by it is approximately 75% of the final adsorption equilibrium amount. It reaches the adsorption equilibrium state at around 120 minutes. This fast adsorption speed implies that it can quickly reduce the phosphorus concentration in water, which is highly beneficial for practical water treatment operations with time constraints. Another notable aspect is its recyclability. After undergoing 10 cycles of adsorption/desorption experiments, it is found that in the latter 9 cycles, the attenuation of the adsorption equilibrium amount of MgO@CFF is only in the range of 8% to 10%. Such a low attenuation rate demonstrates its excellent regeneration ability, meaning that it can be reused multiple times without significant loss of adsorption performance, thereby reducing the overall cost and environmental impact associated with the adsorbent replacement. It is of particular interest that through a series of advanced characterization means, it has been verified that MgO@CFF mainly implements radial linear chemical precipitation adsorption for phosphate. This unique adsorption mechanism is rather distinct and has been scarcely reported in previous studies. It provides new insights into the understanding of how this adsorbent interacts with phosphorus in water and might inspire further research in this field. In conclusion, the fibrous phosphorus adsorbent MgO@CFF has multiple appealing features such as high adsorption efficiency, rapid adsorption speed, strong selectivity for phosphorus, and ease of separation from water. Given these advantages, it holds great promise and is likely to have broad application prospects in phosphorus removal from water bodies, contributing to quality improvement and sustainable management of water resources.
In the context of addressing the ever-increasing issue of phosphorus pollution in water bodies, the adsorption method has emerged as a promising approach. However, for an adsorbent to be truly viable in practical applications, its adsorption performance and recyclability play pivotal roles. These two aspects determine whether it can effectively remove phosphorus from water over an extended period and be reused economically and eco-friendly. Through a relatively straightforward yet effective impregnation-calcination technique, a novel magnesium-modified fibrous phosphate adsorbent, denoted as MgO@CFF, was successfully fabricated. This adsorbent was designed to possess both remarkable adsorption performance and satisfactory recyclability, aiming to overcome the limitations of many existing adsorbents in dealing with phosphorus-contaminated water. Subsequently, a series of comprehensive experiments were carried out with the MgO@CFF as the focus. Specifically, its performance was meticulously evaluated under diverse conditions that mimic real-world water environments, including different initial phosphorus concentrations, the presence of various coexisting ions, and a wide range of pH values. The obtained experimental results are quite significant. Firstly, within a broad pH interval spanning from 3 to 7, the maximum adsorption capacity of MgO@CFF can reach an impressive value of 11.23 mg-P/g. This indicates its robustness in handling phosphorus under a relatively wide range of acidity and alkalinity conditions that are common in natural and industrial water systems. Secondly, even when confronted with different types of foreign anions in the water, MgO@CFF still showcases its outstanding ability to selectively adsorb phosphate, with a preferential selectivity exceeding 50%. Furthermore, in terms of the adsorption kinetics, MgO@CFF exhibits a remarkable characteristic of rapid adsorption. At the 60-minute mark during the adsorption process, the amount of phosphorus adsorbed by it is approximately 75% of the final adsorption equilibrium amount. It reaches the adsorption equilibrium state at around 120 minutes. This fast adsorption speed implies that it can quickly reduce the phosphorus concentration in water, which is highly beneficial for practical water treatment operations with time constraints. Another notable aspect is its recyclability. After undergoing 10 cycles of adsorption/desorption experiments, it is found that in the latter 9 cycles, the attenuation of the adsorption equilibrium amount of MgO@CFF is only in the range of 8% to 10%. Such a low attenuation rate demonstrates its excellent regeneration ability, meaning that it can be reused multiple times without significant loss of adsorption performance, thereby reducing the overall cost and environmental impact associated with the adsorbent replacement. It is of particular interest that through a series of advanced characterization means, it has been verified that MgO@CFF mainly implements radial linear chemical precipitation adsorption for phosphate. This unique adsorption mechanism is rather distinct and has been scarcely reported in previous studies. It provides new insights into the understanding of how this adsorbent interacts with phosphorus in water and might inspire further research in this field. In conclusion, the fibrous phosphorus adsorbent MgO@CFF has multiple appealing features such as high adsorption efficiency, rapid adsorption speed, strong selectivity for phosphorus, and ease of separation from water. Given these advantages, it holds great promise and is likely to have broad application prospects in phosphorus removal from water bodies, contributing to quality improvement and sustainable management of water resources.
2025,
43(1):
118-124.
doi: 10.13205/j.hjgc.202501013
Abstract:
Affected by low temperature and low pressure, the microbial activity of wastewater treatment plants in plateau area is lower, nitrogen and phosphorus concentration in the effluent is generally higher, and the energy consumption and drug consumption usually remain a high level. In this study, an A2/O-MBR process was selected to study the effects of DO concentration and C/N ratio on nitrogen and phosphorus removal performance of a wastewater treatment system at low temperature. The results showed that when the water temperature in the reactor was 10 ℃, the HRT was 12 h, and the reflux ratio of the two-stage mixture was 200%, the MLSS of the system was 7000 mg/L, far higher than the traditional activated sludge process, and that overcome the lack of microbial activity caused by low temperature to some extent; when DO concentration was 1.0~1.5 mg/L, the denitrification performance of the system was the best, and the average removal rates of NH4+-N and TN were 99.80% and 91.28%, far exceeding the first-class A standard in the Integrated Wastewater Discharge Standard. When DO was too low, it mainly affected the nitrification ability of the system, thus affecting its denitrification performance; when C/N was 5, the average removal rates of NH4+-N and TN were 99.80% and 91.28%, respectively, and the system achieved good nitrogen removal performance. When C/N was too low, denitrification was inhibited, which affected the nitrogen removal performance; under different DO concentrations and C/N ratios, the average removal rate of TP could be stabilized at 95% above, complying with the first-class A standard. Based on the results, the aeration of plateau sewage treatment plants in daily operation can be properly reduced, to reduce the total energy consumption. The research results can also provide reference for improving the efficiency of sewage treatment systems under low temperature condition.
Affected by low temperature and low pressure, the microbial activity of wastewater treatment plants in plateau area is lower, nitrogen and phosphorus concentration in the effluent is generally higher, and the energy consumption and drug consumption usually remain a high level. In this study, an A2/O-MBR process was selected to study the effects of DO concentration and C/N ratio on nitrogen and phosphorus removal performance of a wastewater treatment system at low temperature. The results showed that when the water temperature in the reactor was 10 ℃, the HRT was 12 h, and the reflux ratio of the two-stage mixture was 200%, the MLSS of the system was 7000 mg/L, far higher than the traditional activated sludge process, and that overcome the lack of microbial activity caused by low temperature to some extent; when DO concentration was 1.0~1.5 mg/L, the denitrification performance of the system was the best, and the average removal rates of NH4+-N and TN were 99.80% and 91.28%, far exceeding the first-class A standard in the Integrated Wastewater Discharge Standard. When DO was too low, it mainly affected the nitrification ability of the system, thus affecting its denitrification performance; when C/N was 5, the average removal rates of NH4+-N and TN were 99.80% and 91.28%, respectively, and the system achieved good nitrogen removal performance. When C/N was too low, denitrification was inhibited, which affected the nitrogen removal performance; under different DO concentrations and C/N ratios, the average removal rate of TP could be stabilized at 95% above, complying with the first-class A standard. Based on the results, the aeration of plateau sewage treatment plants in daily operation can be properly reduced, to reduce the total energy consumption. The research results can also provide reference for improving the efficiency of sewage treatment systems under low temperature condition.
2025,
43(1):
125-134.
doi: 10.13205/j.hjgc.202501014
Abstract:
In order to improve urban waterlogging, rain flood damage, and scarce water resources, China pays more and more attention to collecting and utilizing rainwater, and actively promotes the concept of "sponge city". For giving full play to the effect of rainwater harvesting systems and measuring their value, this study aimed to establish the evaluation model of the comprehensive benefits of rainwater harvesting systems by adopting emergy analysis method. The method quantifies the input and output of material flow, energy flow and monetary flow into solar energy value through emergy conversion technology. Taking a typical office building as a comprehensive case study, this paper calculated the basic value indexes of the three stages of the total collection life cycle, including construction phase, operation phase and scrap and demolition phase. This paper selected the emergy evaluation indexes of ecological environment, economy and society to calculate the results. Thus, the results of emergy evaluation indexes were calculated by the formula, the benefit output of the system was analyzed, and the results were evaluated. The results showed that the emergy input of the rainwater harvesting system was 2.45E+18sej. Remarkably, the emergy output reached an impressive level of 5.61E+18sej, which was much larger than the input energy. This striking disparity fully demonstrated that the output emergy far exceeded the input emergy, underscoring the system’s remarkable effectiveness and efficiency. The system has demonstrated significant output benefits across multiple dimensions, including economic performance, social benefits, and ecological environmental protection. Among them, the ecological environment benefits accounted for 92.90%, especially in biodiversity protection, annual runoff pollution removal and water supply. During the operation phase, the emergy/environment sustainability index (ESI) of the system was 0.8256, showing the system’s sustainable development ability. A high ESI value indicated that the system pursued economic benefits while fully considering environmental protection and social responsibility. This comprehensive benefit evaluation method based on emergy value analysis can evaluate the benefits of rainwater harvesting systems in the construction and operation phase from the perspective of resource flow, and provide a reference for the evaluation of urban rainwater harvesting and utilization systems.
In order to improve urban waterlogging, rain flood damage, and scarce water resources, China pays more and more attention to collecting and utilizing rainwater, and actively promotes the concept of "sponge city". For giving full play to the effect of rainwater harvesting systems and measuring their value, this study aimed to establish the evaluation model of the comprehensive benefits of rainwater harvesting systems by adopting emergy analysis method. The method quantifies the input and output of material flow, energy flow and monetary flow into solar energy value through emergy conversion technology. Taking a typical office building as a comprehensive case study, this paper calculated the basic value indexes of the three stages of the total collection life cycle, including construction phase, operation phase and scrap and demolition phase. This paper selected the emergy evaluation indexes of ecological environment, economy and society to calculate the results. Thus, the results of emergy evaluation indexes were calculated by the formula, the benefit output of the system was analyzed, and the results were evaluated. The results showed that the emergy input of the rainwater harvesting system was 2.45E+18sej. Remarkably, the emergy output reached an impressive level of 5.61E+18sej, which was much larger than the input energy. This striking disparity fully demonstrated that the output emergy far exceeded the input emergy, underscoring the system’s remarkable effectiveness and efficiency. The system has demonstrated significant output benefits across multiple dimensions, including economic performance, social benefits, and ecological environmental protection. Among them, the ecological environment benefits accounted for 92.90%, especially in biodiversity protection, annual runoff pollution removal and water supply. During the operation phase, the emergy/environment sustainability index (ESI) of the system was 0.8256, showing the system’s sustainable development ability. A high ESI value indicated that the system pursued economic benefits while fully considering environmental protection and social responsibility. This comprehensive benefit evaluation method based on emergy value analysis can evaluate the benefits of rainwater harvesting systems in the construction and operation phase from the perspective of resource flow, and provide a reference for the evaluation of urban rainwater harvesting and utilization systems.
2025,
43(1):
135-143.
doi: 10.13205/j.hjgc.202501015
Abstract:
Luzhou is located in the southwestern hilly region of China, and the upper reaches of the Yangtze River. Wastewater treatment plants (WWTPs) are not only important parts of urban water pollution control, but also important sources of pollutants in natural water bodies. Understanding the quality characteristics of effluent from the WWTPs in Luzhou is crucial for protecting the water quality of the Yangtze River. This study systematically examined the conventional water quality indicators of the incoming and outgoing water from five municipal WWTPs in Luzhou, which were chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen, and total phosphorus (TP), and further compared them with the surface water quality of the upper reaches of the Yangtze River and the water quality of China’s domestic wastewater treatment plants. The analysis employed a multi-factor assessment method to evaluate the risk of eutrophication in the effluent, alongside the use of EPA Method 1694, to assess the detection frequency, concentration levels, and risk quotients of pharmaceuticals and personal care products (PPCPs) present in the tailwater. The findings indicated that TP concentrations in the effluent from these WWTPs failed to meet the Class Ⅲ surface water quality standards in most cases, with a probability of exceeding ranging from 64.3% to 100%, compared to median levels observed at wastewater treatment plants across China. Consequently, TP was identified as a significant contaminant among conventional pollutants. In the investigation, it was discovered that all five WWTPs grappled with inadequate carbon sources during their denitrification processes. The tailwater was at high risk of eutrophication, and the increasing load of TP pollution entering the Yangtze River ecosystem cannot be ignored. Furthermore, 13 PPCPs were detected in the tailwater, and two of them were identified as posing medium to high ecological risks. Specifically, sulfadiazine was categorized as a high-risk PPCP, while sulfamethoxazole was classified as medium risk. The remaining assessed PPCPs were deemed to present low ecological risks. In terms of the two key pollutants, TP and PPCPs, several targeted recommendations were proposed for enhancing the wastewater treatment processes in Luzhou. First, an appropriate increase was advocated in the dosage of polyferric sulfate (PFS), alongside a transition from type D filters to type Ⅴ filters, to improve the efficiency of phosphorus removal from the effluent. Second, ozone treatment and activated carbon were recommended into the treatment process. These additions were expected to effectively address and remove PPCPs that are resistant to conventional treatment methods. These research insights underscored the pressing need for improvements across the municipal wastewater treatment systems of Luzhou. Implementing the recommended changes will probably lead to a significant reduction in the ecological risks associated with TP and PPCPs, assuring that the quality of the effluent aligns with environmental standards.
Luzhou is located in the southwestern hilly region of China, and the upper reaches of the Yangtze River. Wastewater treatment plants (WWTPs) are not only important parts of urban water pollution control, but also important sources of pollutants in natural water bodies. Understanding the quality characteristics of effluent from the WWTPs in Luzhou is crucial for protecting the water quality of the Yangtze River. This study systematically examined the conventional water quality indicators of the incoming and outgoing water from five municipal WWTPs in Luzhou, which were chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen, and total phosphorus (TP), and further compared them with the surface water quality of the upper reaches of the Yangtze River and the water quality of China’s domestic wastewater treatment plants. The analysis employed a multi-factor assessment method to evaluate the risk of eutrophication in the effluent, alongside the use of EPA Method 1694, to assess the detection frequency, concentration levels, and risk quotients of pharmaceuticals and personal care products (PPCPs) present in the tailwater. The findings indicated that TP concentrations in the effluent from these WWTPs failed to meet the Class Ⅲ surface water quality standards in most cases, with a probability of exceeding ranging from 64.3% to 100%, compared to median levels observed at wastewater treatment plants across China. Consequently, TP was identified as a significant contaminant among conventional pollutants. In the investigation, it was discovered that all five WWTPs grappled with inadequate carbon sources during their denitrification processes. The tailwater was at high risk of eutrophication, and the increasing load of TP pollution entering the Yangtze River ecosystem cannot be ignored. Furthermore, 13 PPCPs were detected in the tailwater, and two of them were identified as posing medium to high ecological risks. Specifically, sulfadiazine was categorized as a high-risk PPCP, while sulfamethoxazole was classified as medium risk. The remaining assessed PPCPs were deemed to present low ecological risks. In terms of the two key pollutants, TP and PPCPs, several targeted recommendations were proposed for enhancing the wastewater treatment processes in Luzhou. First, an appropriate increase was advocated in the dosage of polyferric sulfate (PFS), alongside a transition from type D filters to type Ⅴ filters, to improve the efficiency of phosphorus removal from the effluent. Second, ozone treatment and activated carbon were recommended into the treatment process. These additions were expected to effectively address and remove PPCPs that are resistant to conventional treatment methods. These research insights underscored the pressing need for improvements across the municipal wastewater treatment systems of Luzhou. Implementing the recommended changes will probably lead to a significant reduction in the ecological risks associated with TP and PPCPs, assuring that the quality of the effluent aligns with environmental standards.
2025,
43(1):
144-154.
doi: 10.13205/j.hjgc.202501016
Abstract:
In recent years, overflow pollution from municipal drainage systems has become a critical issue that affects the improvement of the urban water environment in many Chinese cities. The causes of overflow pollution are complex, with the main sources including combined sewer overflows, diverted sewage connections, stormwater runoff pollution, and pipe network sediments. In order to ameliorate the overflow pollution problem within a short period, the use of rainwater storage facilities in conjunction with in-situ purification at pumping stations is a feasible means. This study explored the feasibility of the magnetic coagulation process for overflow pollution reduction and carried out the optimization of process parameters. The results showed that the optimum magnetic coagulation conditions were: coagulant polyaluminum chloride (PAC), coagulation aid polyacrylic amide (PAM), and magnetic powder with dosages of 100, 1.00 and 100 mg/L, respectively; with the size of magnetic powder at 300 mesh and the optimum dosing order of magnetic powder-PAC-PAM. Under the optimum conditions, the average concentrations of COD and TP in the effluent of overflow wastewater after magnetic coagulation treatment were 12±8.83 and 0.03±0.03 mg/L, complying with China’s Surface Water Quality Standard: Class Ⅲ. Meanwhile, it was found that there was a significant positive correlation between the removal of COD, turbidity, SS and TP, where a high SS contribution can be a representative indicator. Therefore, the empirical equation for adjusting the dosage of chemicals was established based on the variation of SS concentration in the influent, which can cope with the complex and variable influent water quality in practical applications. This study can provide a reference for in-situ purification of overflow pollution.
In recent years, overflow pollution from municipal drainage systems has become a critical issue that affects the improvement of the urban water environment in many Chinese cities. The causes of overflow pollution are complex, with the main sources including combined sewer overflows, diverted sewage connections, stormwater runoff pollution, and pipe network sediments. In order to ameliorate the overflow pollution problem within a short period, the use of rainwater storage facilities in conjunction with in-situ purification at pumping stations is a feasible means. This study explored the feasibility of the magnetic coagulation process for overflow pollution reduction and carried out the optimization of process parameters. The results showed that the optimum magnetic coagulation conditions were: coagulant polyaluminum chloride (PAC), coagulation aid polyacrylic amide (PAM), and magnetic powder with dosages of 100, 1.00 and 100 mg/L, respectively; with the size of magnetic powder at 300 mesh and the optimum dosing order of magnetic powder-PAC-PAM. Under the optimum conditions, the average concentrations of COD and TP in the effluent of overflow wastewater after magnetic coagulation treatment were 12±8.83 and 0.03±0.03 mg/L, complying with China’s Surface Water Quality Standard: Class Ⅲ. Meanwhile, it was found that there was a significant positive correlation between the removal of COD, turbidity, SS and TP, where a high SS contribution can be a representative indicator. Therefore, the empirical equation for adjusting the dosage of chemicals was established based on the variation of SS concentration in the influent, which can cope with the complex and variable influent water quality in practical applications. This study can provide a reference for in-situ purification of overflow pollution.
2025,
43(1):
155-166.
doi: 10.13205/j.hjgc.202501017
Abstract:
To comprehend the disparities in the deposition characteristics of SNA ions in fine particulate matter in eastern China, this study initially utilized PM2.5 concentration data from 98 cities in the region spanning from 2015 to 2022. The data underwent analysis via the K-means algorithm and were categorized into three groups: LPC, MPC, and HPC, based on ascending concentration levels. The findings revealed a decreasing trend in the daily average PM2.5 concentration across most cities. However, noteworthy distinctions emerged among cities categorized under different attributes, with the distribution of types closely linked to regional location. The study employed the WRF/CAMx model to simulate particulate matter fractions and wet and dry deposition rates in six representative cities: Jinan, Zhengzhou, Hefei, Nanjing, Hangzhou, and Shanghai. It revealed significant seasonal variations in important water-soluble ions, namely SNA ions (NO3-, SO42-, and NH4+), within PM2.5. Specifically, in January, the mass concentration of NO3- in MPC-type cities was approximately 1.46 to 1.88 times higher than that in HPC and LPC-type cities. However, this discrepancy decreased in April, July, and October, resulting in a narrowed difference between different categories. Similar patterns were observed for NH4+, while SO42- exhibited relatively lower concentration levels with the least significant differences. Furthermore, the simulation results indicated that wet deposition fluxes of various ionic components were not only correlated with PM2.5 concentration and ion mass concentration but also significantly influenced by precipitation. Dry and wet deposition continuously and steadily reduced the concentration of particulate matter in the air, especially in the later stages of the pollution process. Its contribution was more significant. By comparing the difference in wet sedimentation flux and precipitation between different cities, it was concluded that SNA ion wet sedimentation flux was the result of the combined action of precipitation and ion mass concentration. The natural sedimentation process was one of the stable and continuous removal mechanisms of fine particles in the atmosphere. The dry sedimentation effect was more significant in northern cities, and the wet sedimentation effect was more frequent in southern cities. Later in the pollution process, the contribution of sedimentation became more prominent.
To comprehend the disparities in the deposition characteristics of SNA ions in fine particulate matter in eastern China, this study initially utilized PM2.5 concentration data from 98 cities in the region spanning from 2015 to 2022. The data underwent analysis via the K-means algorithm and were categorized into three groups: LPC, MPC, and HPC, based on ascending concentration levels. The findings revealed a decreasing trend in the daily average PM2.5 concentration across most cities. However, noteworthy distinctions emerged among cities categorized under different attributes, with the distribution of types closely linked to regional location. The study employed the WRF/CAMx model to simulate particulate matter fractions and wet and dry deposition rates in six representative cities: Jinan, Zhengzhou, Hefei, Nanjing, Hangzhou, and Shanghai. It revealed significant seasonal variations in important water-soluble ions, namely SNA ions (NO3-, SO42-, and NH4+), within PM2.5. Specifically, in January, the mass concentration of NO3- in MPC-type cities was approximately 1.46 to 1.88 times higher than that in HPC and LPC-type cities. However, this discrepancy decreased in April, July, and October, resulting in a narrowed difference between different categories. Similar patterns were observed for NH4+, while SO42- exhibited relatively lower concentration levels with the least significant differences. Furthermore, the simulation results indicated that wet deposition fluxes of various ionic components were not only correlated with PM2.5 concentration and ion mass concentration but also significantly influenced by precipitation. Dry and wet deposition continuously and steadily reduced the concentration of particulate matter in the air, especially in the later stages of the pollution process. Its contribution was more significant. By comparing the difference in wet sedimentation flux and precipitation between different cities, it was concluded that SNA ion wet sedimentation flux was the result of the combined action of precipitation and ion mass concentration. The natural sedimentation process was one of the stable and continuous removal mechanisms of fine particles in the atmosphere. The dry sedimentation effect was more significant in northern cities, and the wet sedimentation effect was more frequent in southern cities. Later in the pollution process, the contribution of sedimentation became more prominent.
2025,
43(1):
167-174.
doi: 10.13205/j.hjgc.202501018
Abstract:
Down-fired boilers are designed to burn low-volatile coal, of which the NOx emission is much higher than that of conventional coal-fired boilers. With the proposal of ultra-low emission standards for thermal power units, the efficient and low-cost reduction of NOx emission in down-fired boilers has become a key issue to be solved urgently. Experiments were conducted in a high-temperature drop tube furnace to investigate the effects of excess air ratio (λ), NH3/NOx molar ratio (NSR), temperature, etc. on the NOx reduction characteristics during anthracite coal combustion by urea solution injection into the high-temperature fuel-rich zone. The experimental results indicated that air-staging combustion could lower approximately 30% of NOx emissions when the excess air ratio was decreased from 1.05 to 0.75. NOx emissions could be further lowered by urea solution injection into a high-temperature reduction zone based on air-staging combustion, and a lower excess air ratio and higher temperature were conducive to the NOx reduction efficiency of urea solution. The optimal NH3/NOx molar ratio was 1.5 under 1400 ℃ or oxidizing atmosphere. However, the optimal NH3/NOx molar ratio was shifted to 2.0 under relatively lower temperatures and a reducing atmosphere. Urea solution injection into a high-temperature fuel-rich zone could reduce 34.27% of NOx emissions and achieve a minimum NOx emission of 438.30 mg/Nm3 under the optimal experimental conditions, i.e., temperature of 1400 ℃, excess air ratio of 0.75, NH3/NOx molar ratio of 1.5. Our findings verify the effectiveness of urea solution injection into the high-temperature fuel-rich zone in lowering NOx emission in down-fired boilers burning anthracite coal.
Down-fired boilers are designed to burn low-volatile coal, of which the NOx emission is much higher than that of conventional coal-fired boilers. With the proposal of ultra-low emission standards for thermal power units, the efficient and low-cost reduction of NOx emission in down-fired boilers has become a key issue to be solved urgently. Experiments were conducted in a high-temperature drop tube furnace to investigate the effects of excess air ratio (λ), NH3/NOx molar ratio (NSR), temperature, etc. on the NOx reduction characteristics during anthracite coal combustion by urea solution injection into the high-temperature fuel-rich zone. The experimental results indicated that air-staging combustion could lower approximately 30% of NOx emissions when the excess air ratio was decreased from 1.05 to 0.75. NOx emissions could be further lowered by urea solution injection into a high-temperature reduction zone based on air-staging combustion, and a lower excess air ratio and higher temperature were conducive to the NOx reduction efficiency of urea solution. The optimal NH3/NOx molar ratio was 1.5 under 1400 ℃ or oxidizing atmosphere. However, the optimal NH3/NOx molar ratio was shifted to 2.0 under relatively lower temperatures and a reducing atmosphere. Urea solution injection into a high-temperature fuel-rich zone could reduce 34.27% of NOx emissions and achieve a minimum NOx emission of 438.30 mg/Nm3 under the optimal experimental conditions, i.e., temperature of 1400 ℃, excess air ratio of 0.75, NH3/NOx molar ratio of 1.5. Our findings verify the effectiveness of urea solution injection into the high-temperature fuel-rich zone in lowering NOx emission in down-fired boilers burning anthracite coal.
2025,
43(1):
175-184.
doi: 10.13205/j.hjgc.202501019
Abstract:
Catalytic oxidation is the most effective way to treat CVOCs. At present, the core difficulties in making efficient CVOCs catalysts are achieving high activity, resistance to chlorine poisoning and resistance to high temperature sintering. In this experiment, a series of hydroxyapatite (HAP(X), X refers to the Ca/P molar ratio) with different Ca/P molar ratios were prepared by liquid phase deposition method, and then ruthenium (Ru) was loaded on the surface of HAP(X) by urea homogeneous deposition precipitation method to prepare the Ru/HAP(X) catalyst. As shown by the results of XRD, FT-IR, SEM, TEM, H2-TPR, NH3-TPD, etc., Ru nanoparticles were highly dispersed on the surface of HAP, and Ru/HAP(1.67) exhibited the best low-temperature reducibility, as well as the richest medium and strong acid sites. The catalytic oxidation activity, selectivity, and stability of Ru/HAP(X) for dichloromethane (DCM) were investigated by taking DCM as typical chlorine-containing VOCs. The investigation result indicated that Ru/HAP(1.67) had the best catalytic oxidation performance and good stability for DCM. The Ca/P molar ratio had a significant effect on the distribution of by-products in the DCM reaction. Monochloromethane, an incomplete decomposition product, was detected in Ru/HAP (1.50) because of its strong acidity. With the increase in Ca/P molar ratio, trichloromethane and tetrachloromethane were the main by-products of Ru/HAP(1.60) and Ru/HAP(1.67). The research results provide references for industrial application of CVOCs catalytic oxidation and high value-added utilization of phosphorus resources.
Catalytic oxidation is the most effective way to treat CVOCs. At present, the core difficulties in making efficient CVOCs catalysts are achieving high activity, resistance to chlorine poisoning and resistance to high temperature sintering. In this experiment, a series of hydroxyapatite (HAP(X), X refers to the Ca/P molar ratio) with different Ca/P molar ratios were prepared by liquid phase deposition method, and then ruthenium (Ru) was loaded on the surface of HAP(X) by urea homogeneous deposition precipitation method to prepare the Ru/HAP(X) catalyst. As shown by the results of XRD, FT-IR, SEM, TEM, H2-TPR, NH3-TPD, etc., Ru nanoparticles were highly dispersed on the surface of HAP, and Ru/HAP(1.67) exhibited the best low-temperature reducibility, as well as the richest medium and strong acid sites. The catalytic oxidation activity, selectivity, and stability of Ru/HAP(X) for dichloromethane (DCM) were investigated by taking DCM as typical chlorine-containing VOCs. The investigation result indicated that Ru/HAP(1.67) had the best catalytic oxidation performance and good stability for DCM. The Ca/P molar ratio had a significant effect on the distribution of by-products in the DCM reaction. Monochloromethane, an incomplete decomposition product, was detected in Ru/HAP (1.50) because of its strong acidity. With the increase in Ca/P molar ratio, trichloromethane and tetrachloromethane were the main by-products of Ru/HAP(1.60) and Ru/HAP(1.67). The research results provide references for industrial application of CVOCs catalytic oxidation and high value-added utilization of phosphorus resources.
2025,
43(1):
185-194.
doi: 10.13205/j.hjgc.202501020
Abstract:
Biogas engineering is a rural energy project aiming at developing and utilizing livestock manure to achieve a virtuous cycle of agricultural ecology. Intelligent monitoring technology can improve the stability of engineering operations by collecting and monitoring various indicators during the operation process of biogas engineering. This article analyzes the main monitoring technologies, automation control technologies, and equipment research and development applications of biogas engineering. The results indicate that the monitoring and control technology of biogas engineering currently has problems such as incomplete monitoring indicators system, low sensor service life, and low automation level; to further improve the intelligence level of biogas engineering, in-depth research should be conducted on the fermentation process mechanism, and the development of high-precision and long-life monitoring sensors suitable for practical biogas engineering should be improved. The application of emerging network technologies such as animal networking in practical engineering should be promoted to improve the efficiency of intelligent operation. Based on the review of biogas engineering monitoring technology, combined with the current relatively mature technology, this paper took the PLC control system as an example to build a set of reliable, feasible, low-cost, and easy to promote biogas engineering intelligent monitoring systems, to build a set of intelligent biogas engineering monitoring systems to achieve the monitoring of various indicators of the biogas engineering system, automatic feeding, heating, stirring, etc. The operation stability of the whole system is improved, which provides a reference for the intelligent monitoring technology of biogas engineering.
Biogas engineering is a rural energy project aiming at developing and utilizing livestock manure to achieve a virtuous cycle of agricultural ecology. Intelligent monitoring technology can improve the stability of engineering operations by collecting and monitoring various indicators during the operation process of biogas engineering. This article analyzes the main monitoring technologies, automation control technologies, and equipment research and development applications of biogas engineering. The results indicate that the monitoring and control technology of biogas engineering currently has problems such as incomplete monitoring indicators system, low sensor service life, and low automation level; to further improve the intelligence level of biogas engineering, in-depth research should be conducted on the fermentation process mechanism, and the development of high-precision and long-life monitoring sensors suitable for practical biogas engineering should be improved. The application of emerging network technologies such as animal networking in practical engineering should be promoted to improve the efficiency of intelligent operation. Based on the review of biogas engineering monitoring technology, combined with the current relatively mature technology, this paper took the PLC control system as an example to build a set of reliable, feasible, low-cost, and easy to promote biogas engineering intelligent monitoring systems, to build a set of intelligent biogas engineering monitoring systems to achieve the monitoring of various indicators of the biogas engineering system, automatic feeding, heating, stirring, etc. The operation stability of the whole system is improved, which provides a reference for the intelligent monitoring technology of biogas engineering.
2025,
43(1):
195-203.
doi: 10.13205/j.hjgc.202501021
Abstract:
Aluminum sludge, a geopolymer with high aluminum content, can be used as a supplementary cementitious material to improve the corrosion resistance of concrete. In this study, the effects of two different alkali activators (NaOH and Na2SiO3) on the hydration process of cement-based coating materials under different dosages were investigated by using sludge pretreatment methods of low-temperature calcination combined with alkali activation, and the acid corrosion resistance of the coating was explored. The results showed that the substitution of aluminum sludge ash (ASA) at a low temperature of 350 ℃ with an alkali activator can promote the formation of calcium aluminate hydrate (C-A-H) and calcium aluminosilicate hydrate (C-A-S-H) gel products. The acid corrosion resistance of the coating material with the ratio of 6% Na2SiO3+10% ASA was better than that of ordinary Portland cement, and the coating material can form a layer of acid barrier, Al(OH)3, in the middle stage of corrosion. This work provides a low-energy consumption treatment method for resource utilization of aluminum sludge, and the coating material can be applied in acid-corrosive environment
Aluminum sludge, a geopolymer with high aluminum content, can be used as a supplementary cementitious material to improve the corrosion resistance of concrete. In this study, the effects of two different alkali activators (NaOH and Na2SiO3) on the hydration process of cement-based coating materials under different dosages were investigated by using sludge pretreatment methods of low-temperature calcination combined with alkali activation, and the acid corrosion resistance of the coating was explored. The results showed that the substitution of aluminum sludge ash (ASA) at a low temperature of 350 ℃ with an alkali activator can promote the formation of calcium aluminate hydrate (C-A-H) and calcium aluminosilicate hydrate (C-A-S-H) gel products. The acid corrosion resistance of the coating material with the ratio of 6% Na2SiO3+10% ASA was better than that of ordinary Portland cement, and the coating material can form a layer of acid barrier, Al(OH)3, in the middle stage of corrosion. This work provides a low-energy consumption treatment method for resource utilization of aluminum sludge, and the coating material can be applied in acid-corrosive environment
Design of remediation process for volatile organic pollution sites with air sparging based on TOUGH2
2025,
43(1):
204-210.
doi: 10.13205/j.hjgc.202501022
Abstract:
The air sparging method is a crucial technology for addressing organic contamination in groundwater and soil. When integrated with numerical simulation, this approach allows for the optimization of remediation conditions, thereby enhancing the effectiveness of the remediation process. This paper utilized the T2VOC module of TOUGH2 software, to simulate and investigate the transport mechanisms of para-xylene during the processes of leakage, redistribution, and air sparging remediation within a specified study area. The findings of this research indicated that during the leakage of contaminants, para-xylene in the unsaturated zone underwent vertical migration and lateral expansion due to the combined effects of gravitational and capillary forces. In contrast, para-xylene in the saturated zone primarily experienced horizontal diffusion and subsequently dissolved into the groundwater, which complicated the spread of contamination. Furthermore, by taking the specific site conditions of the study area into account, including soil permeability and groundwater level, this study identified the optimal aeration flow rate at 12 m3/h and the aeration depth at 10.4 m. These results provide significant insights into the behavior of para-xylene contaminants and contribute to the development of more effective remediation strategies for contaminated sites. Overall, this research highlighted the importance of integrating numerical modeling with traditional remediation techniques, offering a promising direction for improving the management of organic pollutants in subsurface environments. Thus, it lays a foundational understanding for future studies aimed at refining remediation practices and addressing environmental challenges related to soil and groundwater contamination.
The air sparging method is a crucial technology for addressing organic contamination in groundwater and soil. When integrated with numerical simulation, this approach allows for the optimization of remediation conditions, thereby enhancing the effectiveness of the remediation process. This paper utilized the T2VOC module of TOUGH2 software, to simulate and investigate the transport mechanisms of para-xylene during the processes of leakage, redistribution, and air sparging remediation within a specified study area. The findings of this research indicated that during the leakage of contaminants, para-xylene in the unsaturated zone underwent vertical migration and lateral expansion due to the combined effects of gravitational and capillary forces. In contrast, para-xylene in the saturated zone primarily experienced horizontal diffusion and subsequently dissolved into the groundwater, which complicated the spread of contamination. Furthermore, by taking the specific site conditions of the study area into account, including soil permeability and groundwater level, this study identified the optimal aeration flow rate at 12 m3/h and the aeration depth at 10.4 m. These results provide significant insights into the behavior of para-xylene contaminants and contribute to the development of more effective remediation strategies for contaminated sites. Overall, this research highlighted the importance of integrating numerical modeling with traditional remediation techniques, offering a promising direction for improving the management of organic pollutants in subsurface environments. Thus, it lays a foundational understanding for future studies aimed at refining remediation practices and addressing environmental challenges related to soil and groundwater contamination.
2025,
43(1):
211-222.
doi: 10.13205/j.hjgc.202501023
Abstract:
The scientific selection of appropriate combined remediation technologies represents a significant challenge in the environmental governance of petrochemical agglomerations. This study proposed a comprehensive screening system for combined remediation technologies specifically designed for petrochemical agglomerations. This screening methodology system encompassed several critical components aiming at enhancing remediation outcomes. Firstly, the system included the development of a comprehensive remediation database tailored for petrochemical contamination sites. This database served as a centralized repository of relevant information, facilitating data analysis and informed decision-making. Secondly, the establishment of a screening indicator system was vital. This system was designed to evaluate the efficacy of various remediation technologies based on key performance metrics. In addition to these components, a weighting calculation method for the screening indicators was formulated. This method allowed for the prioritization of indicators, ensuring that the most impactful factors were duly considered during the selection process. Furthermore, the Technique for Order of Preference by Similarity to an Ideal Solution (TOPSIS) was employed. This quantitative method effectively ranked and selected alternative combined remediation technologies. Based on this framework, a remediation technology screening assistance system was developed, and successfully implemented at a contaminated petrochemical site in Nanjing, Jiangsu Province in China. The results indicated that the optimal combination of remediation technologies included natural attenuation, pump and treat-injection cyclic, and in-situ chemical oxidation. Notably, this combination demonstrated a high degree of consistency with the actual application of the site, confirming the efficacy of the proposed screening methodology in practical applications. In conclusion, these findings not only offer a solid methodological foundation for addressing the specific challenges associated with selecting combined remediation technologies for petrochemical-contaminated sites, but also provide practical guidance for real projects.
The scientific selection of appropriate combined remediation technologies represents a significant challenge in the environmental governance of petrochemical agglomerations. This study proposed a comprehensive screening system for combined remediation technologies specifically designed for petrochemical agglomerations. This screening methodology system encompassed several critical components aiming at enhancing remediation outcomes. Firstly, the system included the development of a comprehensive remediation database tailored for petrochemical contamination sites. This database served as a centralized repository of relevant information, facilitating data analysis and informed decision-making. Secondly, the establishment of a screening indicator system was vital. This system was designed to evaluate the efficacy of various remediation technologies based on key performance metrics. In addition to these components, a weighting calculation method for the screening indicators was formulated. This method allowed for the prioritization of indicators, ensuring that the most impactful factors were duly considered during the selection process. Furthermore, the Technique for Order of Preference by Similarity to an Ideal Solution (TOPSIS) was employed. This quantitative method effectively ranked and selected alternative combined remediation technologies. Based on this framework, a remediation technology screening assistance system was developed, and successfully implemented at a contaminated petrochemical site in Nanjing, Jiangsu Province in China. The results indicated that the optimal combination of remediation technologies included natural attenuation, pump and treat-injection cyclic, and in-situ chemical oxidation. Notably, this combination demonstrated a high degree of consistency with the actual application of the site, confirming the efficacy of the proposed screening methodology in practical applications. In conclusion, these findings not only offer a solid methodological foundation for addressing the specific challenges associated with selecting combined remediation technologies for petrochemical-contaminated sites, but also provide practical guidance for real projects.
