Reservoirs have been served as the major source of drinking water for dozens of years.The water quality safety of large andmedium reservoirs increasingly becomes the focus of public concern.Field test has proved that ...Reservoirs have been served as the major source of drinking water for dozens of years.The water quality safety of large andmedium reservoirs increasingly becomes the focus of public concern.Field test has proved that water-lifting and aeration system(WLAS)is a piece of effective equipment for in situ control and improvement of water quality.However,its intrinsic bioremediation mechanism,especially for nitrogen removal,still lacks in-depth investigation.Hence,the dynamic changes inwater quality parameters,carbon source metabolism,species compositions and co-occurrence patterns ofmicrobial communitieswere systematically studied in Jinpen Reservoir within a wholeWLAS running cycle.TheWLAS operation could efficiently reduce organic carbon(19.77%),nitrogen(21.55%)and phosphorus(65.60%),respectively.Biolog analysis revealed that the microbialmetabolic capacitieswere enhanced viaWLAS operation,especially in bottomwater.High-throughput sequencing demonstrated that WLAS operation altered the diversity and distributions of microbial communities in the source water.The most dominant genus accountable for aerobic denitrification was identified as Dechloromonas.Furthermore,network analysis revealed that microorganisms interacted more closely through WLAS operation.Oxidation-reduction potential(ORP)and total nitrogen(TN)were regarded as the two main physicochemical parameters influencing microbial community structures,as confirmed by redundancy analysis(RDA)and Mantel test.Overall,the results will provide a scientific basis and an effective way for strengthening the in-situ bioremediation of micro-polluted source water.展开更多
Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used ...Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures（silty,clayey, and sandy soils） along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform（TCM） and trichloroethylene（TCE）. Mechanical soil aeration was effective for remediating VCHs（removal efficiency 〉 98%）. The volatilization process was described by an exponential kinetic function.In the early stage of treatment（0–7 hr）, rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.展开更多
In recent years, many industrial enterprises located in the urban centers of China have been relocated owing to the rapid increase in urban development. At the sites abandoned by these enterprises, volatile organic co...In recent years, many industrial enterprises located in the urban centers of China have been relocated owing to the rapid increase in urban development. At the sites abandoned by these enterprises, volatile organic compounds have frequently been detected, sometimes at high concentrations, particularly at sites abandoned by chemical manufacturing enterprises. With the redevelopment of sites and changes in land-use tvpe associated with these sites, substantial amounts of contaminated soils now require remediation. ＂Since China is a developing country, soil remediation warrants the usage of techniques that are suitable for addressing the unique challenges faced in this country. Land shortage is a common problem in China; the large numbers of contaminated sites, tight development schedules, and limited financial resources necessitate the development of .cost-effective methods for land reclamation.Mechanical soil aeration is a simple, effective, and low-cost soil remediation tectm^que mat is particularly suitable for the remediation of large volatile organic compound-contaminated sites. Its effectiveness has been confirmed by conducting laboratory studies, pilot tests, and full-scale projects.This study reviews current engineei-ing practice and developmental trends of mechanical soil aeration and analyzes the advantages and disadvantages of this technology for application in China as an emerging soil remediation market. The findings of this study might aid technology development in China, as well as assist other developing countries in the assessment and implementation of costeffective hazardous waste site soil remediation programs.展开更多
基金This work was supported by the National Key Research and Development Program of China(No.2019YFD1100101)the National Natural Science Foundation of China(No.51979217)+2 种基金the Shaanxi Provincial Key Research and Development Program(No.2019ZDLSF06-03)the Youth Innovation Team of Shaanxi Universities in 2020(PI:Dr.Haihan Zhang)the Youth Innovation Team of Shaanxi Universities in 2021(No.21JP061).
文摘Reservoirs have been served as the major source of drinking water for dozens of years.The water quality safety of large andmedium reservoirs increasingly becomes the focus of public concern.Field test has proved that water-lifting and aeration system(WLAS)is a piece of effective equipment for in situ control and improvement of water quality.However,its intrinsic bioremediation mechanism,especially for nitrogen removal,still lacks in-depth investigation.Hence,the dynamic changes inwater quality parameters,carbon source metabolism,species compositions and co-occurrence patterns ofmicrobial communitieswere systematically studied in Jinpen Reservoir within a wholeWLAS running cycle.TheWLAS operation could efficiently reduce organic carbon(19.77%),nitrogen(21.55%)and phosphorus(65.60%),respectively.Biolog analysis revealed that the microbialmetabolic capacitieswere enhanced viaWLAS operation,especially in bottomwater.High-throughput sequencing demonstrated that WLAS operation altered the diversity and distributions of microbial communities in the source water.The most dominant genus accountable for aerobic denitrification was identified as Dechloromonas.Furthermore,network analysis revealed that microorganisms interacted more closely through WLAS operation.Oxidation-reduction potential(ORP)and total nitrogen(TN)were regarded as the two main physicochemical parameters influencing microbial community structures,as confirmed by redundancy analysis(RDA)and Mantel test.Overall,the results will provide a scientific basis and an effective way for strengthening the in-situ bioremediation of micro-polluted source water.
基金supported by the National Environmental Protection Public Welfare projects(Nos.201409047 and 201109017)the “13th Five-Year Plan” National Key Research and Development Program of China(No.2016YFC0501108)+1 种基金the Fundamental Research Funds for the Central Universities(No.2016QH02)Beijing Natural Science Foundation(No.8152025)
文摘Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures（silty,clayey, and sandy soils） along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform（TCM） and trichloroethylene（TCE）. Mechanical soil aeration was effective for remediating VCHs（removal efficiency 〉 98%）. The volatilization process was described by an exponential kinetic function.In the early stage of treatment（0–7 hr）, rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.
文摘In recent years, many industrial enterprises located in the urban centers of China have been relocated owing to the rapid increase in urban development. At the sites abandoned by these enterprises, volatile organic compounds have frequently been detected, sometimes at high concentrations, particularly at sites abandoned by chemical manufacturing enterprises. With the redevelopment of sites and changes in land-use tvpe associated with these sites, substantial amounts of contaminated soils now require remediation. ＂Since China is a developing country, soil remediation warrants the usage of techniques that are suitable for addressing the unique challenges faced in this country. Land shortage is a common problem in China; the large numbers of contaminated sites, tight development schedules, and limited financial resources necessitate the development of .cost-effective methods for land reclamation.Mechanical soil aeration is a simple, effective, and low-cost soil remediation tectm^que mat is particularly suitable for the remediation of large volatile organic compound-contaminated sites. Its effectiveness has been confirmed by conducting laboratory studies, pilot tests, and full-scale projects.This study reviews current engineei-ing practice and developmental trends of mechanical soil aeration and analyzes the advantages and disadvantages of this technology for application in China as an emerging soil remediation market. The findings of this study might aid technology development in China, as well as assist other developing countries in the assessment and implementation of costeffective hazardous waste site soil remediation programs.
