Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we rese...Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we researched migration and transformation of COD in aerated zone, and put f orward a mathematical model showing the process. The results show that adsorptio n of organism in aerated zone is linear, which is represented by Henry's law s =K dc+s d, adsorption coefficient K d=0.069 3; biodegradati on diagram accord basically with first order kinetics equation c=c 0e -K 1t , biodegradation coefficient K 1 = 0.049 9 d -1 ; dispersio n coefficient D= 0.002 42 m 2/d in experiments. The migration and transform ation of organic pollutants (COD) in aerated zone jointly result from many f actors such as dispersion, adsorption and biodegradation etc..展开更多
Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the ...Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal.展开更多
Recently,more and more attention has been paid to the strong oxidation ability of newly prepared potassium ferrate(NAPF) in sludge reduction process,but less attention has been paid to the change of phosphorus in this...Recently,more and more attention has been paid to the strong oxidation ability of newly prepared potassium ferrate(NAPF) in sludge reduction process,but less attention has been paid to the change of phosphorus in this process.The feasibility of phosphorus migration and transformation during excess sludge reduction pretre atment using NAPF pre-oxidation combined with anaerobic digestion was investigated.After 70 mg/g suspended solids NAPF pretreatment and 16 days anaerobic digestion,the solid-phase volatile suspended solids decreased by 44.2%,and much organic matter had been released into the liquid-phase and then degraded during digestion by indigenous microorganisms.As the sludge pre-oxidation process was performed,solid-phase organic phosphorus and chemically combined phosphorus also released into the liquid-phase as PO4^3-,peaking at 100 mg/L.During anaerobic digestion,the Fe3+in the liquid-phase was gradually reduced to Fe2+,and then formed Fe^2+-PO4^3- compound crystals and re-migrated to the solid-phase.The concentration of PO4^3- decreased to 17.08± 1.1 mg/L in the liquid-phase after anaerobic digestion.Finally,the phosphorus in the Fe^2+-PO4^3- compound accounts for 80% of the total phosphorus in the solid-phase.A large number of vivianite crystals in sludge were observed.Therefore,this technology not only effectively reduces sludge,but also increases the proportion of PO43-in the sludge in the form of Vivianite.展开更多
[Objective] The aim was to provide theoretical basis for field moisture conserving irrigation.[Method] With Xiaoyan No.6 as tested material,three different kinds of mulching irrigation treatments were carried out (st...[Objective] The aim was to provide theoretical basis for field moisture conserving irrigation.[Method] With Xiaoyan No.6 as tested material,three different kinds of mulching irrigation treatments were carried out (straw mulching;plastic mulching;PAM control adjustment mulching).With non-mulching treatment as control,moisture conserving effect of different treatments were compared.[Result] The results showed that the water consumption of winter wheat under different soil moisture conservation treatments was low at earlier stage and later stage,but high at mid-stage,which was consistent with the water consumption law of control.There were some differences in terms of consumption intensity because of irrigation schedule and growth condition;soil moisture conservation treatments could restrain ineffective evaporation of soil moisture before anthesis.We also found that the variation of soil moisture at depth of 0-20 cm in PAM and control treatment was dramatic.The soil moisture of the former was lower than the latter at the depth of 0-20 cm,but higher at the depth of 20-50 cm.The difference of soil moisture at the depth of 0-50 cm was significant.[Conclusion] Plastic mulching and straw mulching could restrain evaporation effectively.展开更多
Pharmaceuticals and personal care products(PPCPs)are a new kind of contaminant widely existing in the surface water and groundwater environment.In recent years,PPCPs have been received widely attention from many resea...Pharmaceuticals and personal care products(PPCPs)are a new kind of contaminant widely existing in the surface water and groundwater environment.In recent years,PPCPs have been received widely attention from many researchers.The migration and transformation of PPCPs are mainly photolysis,biodegradation,adsorption and hydrolysis in aquifer environment.The influencing factors of PPCPs migration include PPCPs’own physical and chemical properties,types and contents of organic matter,pH,lithology,geotechnical structure and the thickness of vadose zone,etc.At present,the research of PPCPs in China is still in the primary stage,especially on the contaminant in aquifer system.Therefore,the research in this field needs to be further strengthened.展开更多
Cyclic injection holds great potential for CO_(2) emission reduction coupled with enhanced unconventional oil recovery.There is,however,a lack of a thorough understanding of carbon distribution,migration,and transform...Cyclic injection holds great potential for CO_(2) emission reduction coupled with enhanced unconventional oil recovery.There is,however,a lack of a thorough understanding of carbon distribution,migration,and transformation underground over time at the reservoir scale.To address this issue,we conducted a rig-orous numerical simulation integrating microseismic events,multi-geomechanics,and multi-geochemistry to represent the complex fracture geometry,rock stress sensitivity,and CO_(2)-oil-brine-rock interactions.The fluid model,reservoir model,and geochemical reaction kinetics were carefully validated and calibrated using experimental data.The performance of CO_(2) utilization and geological storage was comprehensively investigated in terms of changes in oil production,CO_(2) storage,carbon distribution,and petrophysical properties.The results indicate that 48.3%of the injected CO_(2) was stored stably under-ground after ten cycles(ten years),with a 3.4%increase in oil recovery.The presence of multiple CO_(2) stor-age forms,such as dissolved in water and mineralized carbonate,impeded CO_(2)-oil interaction,leading to a 25.9%reduction in the volume of the CO_(2)-oil mixing zone and a 2.2%decrease in cumulative oil pro-duction,albeit with a 7.7%increase in the storage rate.The cyclic injection mode had a significant impact on the migration and transformation of CO_(2) in the reservoir.While dissolved CO_(2) in oil accounted for over half of the total storage,it had the possibility of being released during production.After ten cycles,20%of the injected CO_(2)(approximately 12000 t)reached long-term storage in four forms:mineralized carbon-ate(6%),water-dissolved CO_(2)(6%),aqueous ions(4%),and trapped gas(4%).Notably,the non-fracture zone within the stimulated reservoir volume(SRV)served as the primary trapping area for residual gas.This work provides valuable insights into dynamic CO_(2) transport and transformation processes under cyclic injection and presents a more comprehensive and precise framework for assessing CO_(2) capture,utilization,and storage with enhanced oil recovery(CCUS-EOR)performance in unconventional reser-voirs after fracturing.展开更多
Metal-based engineered nanomaterials(MENMs)are increasingly being used in people’s working lives.Although MENMs have important effects on soil ecosystem and play an important role in solving soil environmental proble...Metal-based engineered nanomaterials(MENMs)are increasingly being used in people’s working lives.Although MENMs have important effects on soil ecosystem and play an important role in solving soil environmental problems,the hazards associated with MENMs cannot be ignored.Therefore,more and more scholars have studied the behavior and effects of nanomaterials in soils in recent years.In this review,we explore the articles on MENMs and soil ecosystem retrieved from various databases from 2013 to 2022.We discuss the mechanisms of MENM toxicity,the current state of soil ecosystem,the ecological effects of MENMs on soil microbes,earthworms,and plants,and the ways by which soil organisms take up MENMs.We now know that although MENMs have positive effects on soil ecosystem,their potential hazards are not negligible.Therefore,it is necessary to investigate the effects of MENMs on soil organisms.Meanwhile,we should pay more attention to the negative effects of MENMs on soil ecosystem while exploring their positive effects on soil ecosystem in future research.展开更多
The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to...The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.展开更多
文摘Collecting waste water with a certain c onc entration of organic pollutants COD (chemical oxygen demand), static adsorption, static biodegradation and dynamic soil column experiments were made in laborato ry, we researched migration and transformation of COD in aerated zone, and put f orward a mathematical model showing the process. The results show that adsorptio n of organism in aerated zone is linear, which is represented by Henry's law s =K dc+s d, adsorption coefficient K d=0.069 3; biodegradati on diagram accord basically with first order kinetics equation c=c 0e -K 1t , biodegradation coefficient K 1 = 0.049 9 d -1 ; dispersio n coefficient D= 0.002 42 m 2/d in experiments. The migration and transform ation of organic pollutants (COD) in aerated zone jointly result from many f actors such as dispersion, adsorption and biodegradation etc..
基金supported by Jilin Provincial Department of Education Science and Technology Project(No.JJKH20230152KJ)the Doctoral Research Initiation Fund(No.BSJXM-2022215).
文摘Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal.
基金supported by the National Natural Science Foundation of China(No.51938010)the Major Science and Technology Projects for Water Pollution Control and Treatment of China(No.2017ZX07205002)+1 种基金National Key Research and Development Programme of China(No.2016YFC0401103)the Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment。
文摘Recently,more and more attention has been paid to the strong oxidation ability of newly prepared potassium ferrate(NAPF) in sludge reduction process,but less attention has been paid to the change of phosphorus in this process.The feasibility of phosphorus migration and transformation during excess sludge reduction pretre atment using NAPF pre-oxidation combined with anaerobic digestion was investigated.After 70 mg/g suspended solids NAPF pretreatment and 16 days anaerobic digestion,the solid-phase volatile suspended solids decreased by 44.2%,and much organic matter had been released into the liquid-phase and then degraded during digestion by indigenous microorganisms.As the sludge pre-oxidation process was performed,solid-phase organic phosphorus and chemically combined phosphorus also released into the liquid-phase as PO4^3-,peaking at 100 mg/L.During anaerobic digestion,the Fe3+in the liquid-phase was gradually reduced to Fe2+,and then formed Fe^2+-PO4^3- compound crystals and re-migrated to the solid-phase.The concentration of PO4^3- decreased to 17.08± 1.1 mg/L in the liquid-phase after anaerobic digestion.Finally,the phosphorus in the Fe^2+-PO4^3- compound accounts for 80% of the total phosphorus in the solid-phase.A large number of vivianite crystals in sludge were observed.Therefore,this technology not only effectively reduces sludge,but also increases the proportion of PO43-in the sludge in the form of Vivianite.
基金Supported by National 863 Project (2006AA100223)Program of Introducing Talents of Discipline to Hydrology Ecological and Water Security in Arid and Semi Arid Areas(B08039)~~
文摘[Objective] The aim was to provide theoretical basis for field moisture conserving irrigation.[Method] With Xiaoyan No.6 as tested material,three different kinds of mulching irrigation treatments were carried out (straw mulching;plastic mulching;PAM control adjustment mulching).With non-mulching treatment as control,moisture conserving effect of different treatments were compared.[Result] The results showed that the water consumption of winter wheat under different soil moisture conservation treatments was low at earlier stage and later stage,but high at mid-stage,which was consistent with the water consumption law of control.There were some differences in terms of consumption intensity because of irrigation schedule and growth condition;soil moisture conservation treatments could restrain ineffective evaporation of soil moisture before anthesis.We also found that the variation of soil moisture at depth of 0-20 cm in PAM and control treatment was dramatic.The soil moisture of the former was lower than the latter at the depth of 0-20 cm,but higher at the depth of 20-50 cm.The difference of soil moisture at the depth of 0-50 cm was significant.[Conclusion] Plastic mulching and straw mulching could restrain evaporation effectively.
基金This study was supported by National Natural Science Foundation of China(No.4197021272).
文摘Pharmaceuticals and personal care products(PPCPs)are a new kind of contaminant widely existing in the surface water and groundwater environment.In recent years,PPCPs have been received widely attention from many researchers.The migration and transformation of PPCPs are mainly photolysis,biodegradation,adsorption and hydrolysis in aquifer environment.The influencing factors of PPCPs migration include PPCPs’own physical and chemical properties,types and contents of organic matter,pH,lithology,geotechnical structure and the thickness of vadose zone,etc.At present,the research of PPCPs in China is still in the primary stage,especially on the contaminant in aquifer system.Therefore,the research in this field needs to be further strengthened.
基金support from the National Key Research and Development Program of China(2023YFE0120700)National Natural Science Foundation of China(52274041)Distinguished Young Sichuan Science Scholars(2023NSFSC1954).
文摘Cyclic injection holds great potential for CO_(2) emission reduction coupled with enhanced unconventional oil recovery.There is,however,a lack of a thorough understanding of carbon distribution,migration,and transformation underground over time at the reservoir scale.To address this issue,we conducted a rig-orous numerical simulation integrating microseismic events,multi-geomechanics,and multi-geochemistry to represent the complex fracture geometry,rock stress sensitivity,and CO_(2)-oil-brine-rock interactions.The fluid model,reservoir model,and geochemical reaction kinetics were carefully validated and calibrated using experimental data.The performance of CO_(2) utilization and geological storage was comprehensively investigated in terms of changes in oil production,CO_(2) storage,carbon distribution,and petrophysical properties.The results indicate that 48.3%of the injected CO_(2) was stored stably under-ground after ten cycles(ten years),with a 3.4%increase in oil recovery.The presence of multiple CO_(2) stor-age forms,such as dissolved in water and mineralized carbonate,impeded CO_(2)-oil interaction,leading to a 25.9%reduction in the volume of the CO_(2)-oil mixing zone and a 2.2%decrease in cumulative oil pro-duction,albeit with a 7.7%increase in the storage rate.The cyclic injection mode had a significant impact on the migration and transformation of CO_(2) in the reservoir.While dissolved CO_(2) in oil accounted for over half of the total storage,it had the possibility of being released during production.After ten cycles,20%of the injected CO_(2)(approximately 12000 t)reached long-term storage in four forms:mineralized carbon-ate(6%),water-dissolved CO_(2)(6%),aqueous ions(4%),and trapped gas(4%).Notably,the non-fracture zone within the stimulated reservoir volume(SRV)served as the primary trapping area for residual gas.This work provides valuable insights into dynamic CO_(2) transport and transformation processes under cyclic injection and presents a more comprehensive and precise framework for assessing CO_(2) capture,utilization,and storage with enhanced oil recovery(CCUS-EOR)performance in unconventional reser-voirs after fracturing.
基金supported by the National Key R&D Program of China(Nos.2017YFD0801300 and 2017YFD 0801103)the National Natural Science Foundation of China(No.41130526)。
文摘Metal-based engineered nanomaterials(MENMs)are increasingly being used in people’s working lives.Although MENMs have important effects on soil ecosystem and play an important role in solving soil environmental problems,the hazards associated with MENMs cannot be ignored.Therefore,more and more scholars have studied the behavior and effects of nanomaterials in soils in recent years.In this review,we explore the articles on MENMs and soil ecosystem retrieved from various databases from 2013 to 2022.We discuss the mechanisms of MENM toxicity,the current state of soil ecosystem,the ecological effects of MENMs on soil microbes,earthworms,and plants,and the ways by which soil organisms take up MENMs.We now know that although MENMs have positive effects on soil ecosystem,their potential hazards are not negligible.Therefore,it is necessary to investigate the effects of MENMs on soil organisms.Meanwhile,we should pay more attention to the negative effects of MENMs on soil ecosystem while exploring their positive effects on soil ecosystem in future research.
基金supported by the Central Public-interest Scientific Institution Basal Research Fund(No.Y2024QC29)the Central Public-interest Scientific Institution Basal Research Fund(Nos.2024-jbkyywf-lwj and 2024-jbkyywf-zyj).
文摘The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.