A new process for utilization of hazardous lead-bearing wastes and iron-rich wastes by reducing-matting smelting has been developed.The slag(SG) and the iron-rich matte(IRM) are the main by-products from reducing-...A new process for utilization of hazardous lead-bearing wastes and iron-rich wastes by reducing-matting smelting has been developed.The slag(SG) and the iron-rich matte(IRM) are the main by-products from reducing-matting smelting of lead-bearing wastes and iron-rich wastes.The environmental risk of heavy metals(Cd,Zn,Pb and As) in the main by-products versus the charging material for reducing-matting smelting(CM) has been systematically assessed using leaching toxicity test,the three-stage sequential extraction procedure of European Community Bureau of Reference(BCR) and Hakanson Potential Ecological Risk Index Method(PERI).The results demonstrate that the ecological risk level of heavy metals for SG and IRM is significantly reduced after the reducing-matting smelting process compared with that for CM.展开更多
Mg2+ and PO43+ were added into the synthetic wastewater, leading to the dissociation of the complex ions in the wastewater, and resulting in removal of copper and ammonia therein. The effects of agents addition amo...Mg2+ and PO43+ were added into the synthetic wastewater, leading to the dissociation of the complex ions in the wastewater, and resulting in removal of copper and ammonia therein. The effects of agents addition amount, pH, and reaction time on the removal efficiency of copper and ammonia were investigated. In particular, two-sectional struvite formation (TSSF) process was established for copper and ammonia removal. MgCl2 and Na2HPO4 were added by following 90% addition in the first section and remained 10% in the second during the TSSF process. Compared with one sectional struvite formation, TSSF possessed much better performance. Under condition of n(NH3-N):n(Mg):n(P)=1:1.2:1.5 (molar ratio), pH=9, and reaction time of 30 min, the removal efficiencies of copper and ammonia were 98.9% and 99.96%, respectively. The enhanced performance of TSSF is explained by the competition of ammonia by copper?ammonia complexes and struvite. The dissociation of copper-ammonia complexes is further demonstrated by thermodynamic equilibrium analysis, on the basis of calculations and establishment of predominance phases diagram. Moreover, XRD and EDS analyses further confirmed the formation of struvite and precipitation of copper, which prove the transmission of copper and ammonia from liquid phase into solid phase.展开更多
The author summarized the advantages and potential risks of urban-rural organic wastes agricultural reutilization to reduce the potential risks of urban-rural organic wastes agricultural utilization. The results showe...The author summarized the advantages and potential risks of urban-rural organic wastes agricultural reutilization to reduce the potential risks of urban-rural organic wastes agricultural utilization. The results showed that: the organic wastes generated in urban-rural life as fertilizer applied into farmland made an impact on soil properties, then indirectly affected the soil microbial biomass and soil enzymes activities. In addition, the heavy metals in organic wastes would accumulate in the soil and damage to soil environment. Therefore, it was necessary to make a long- term research on the environment of soil which agricultural utilized of wastes.展开更多
Soil samples were collected from Zhangshi Wastewater Irrigation Area in the suburb of Shenyang City,China,an area with a 30-year irrigation history with heavy metal-containing wastewater.The chemical properties and mi...Soil samples were collected from Zhangshi Wastewater Irrigation Area in the suburb of Shenyang City,China,an area with a 30-year irrigation history with heavy metal-containing wastewater.The chemical properties and microbial characteristics of the soils were examined to evaluate the present situation of heavy metal pollution and to assess the soil microbial characteristics under long-term heavy metal stress.In light of the National Environmental Quality Standards of China,the soil in the test area was heavily polluted by Cd and to a lesser degree by Zn and Cu,even though wastewater irrigation ceased in 1993.Soil metabolic quotient (qCO_2) had a significant positive correlation,while soil microbial quotient (qM) had a negative correlation with content of soil heavy metals.Soil microbial biomass carbon (MBC) had significantly negative correlation with Cd,but soil substrate-induced respiration (SIR),dehydrogenase activity (DHA),cellulase activity, and culturable microbial populations had no persistent correlations with soil heavy metal content.Soil nutrients,except for phosphorous,showed positive effects on soil microbial characteristics,which to a certain degree obscured the adverse effects of soil heavy metals.Soil Cd contributed more to the soil microbial characteristics,but qM and qCO_2 were more sensitive and showed persistent responses to heavy metals stress.It could be concluded that qM and qCO_2 can be used as bioindicators of heavy metal pollution in soils.展开更多
The effect of moisture in municipal solid waste (MSW) on partitioning of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) was studied in a laboratory tubular furnace by using simulated MSW. The moisture in MSW influ...The effect of moisture in municipal solid waste (MSW) on partitioning of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) was studied in a laboratory tubular furnace by using simulated MSW. The moisture in MSW influences heavy metals in following ways, to increase the moisture in flue gas and decrease the combustion temperature, to prolong the combustion time, and to prolong the releasing time of volatiles with the furnace temperature decreased by increasing the moisture. The volatilization of Pb, Zn and Cd was enhanced by increasing the moisture in MSW because of the prolonged combustion time. For Pb and Zn, the combustion time was important at higher temperature, while for Cd, it was important at low temperature. The moisture content showed slight effect on Cu partitioning. When extra chlorine was added to MSW, such as 1%PVC + 0.5%NaCl, the volatilization of Pb, Zn and Cu was enhanced by increasing the moisture because water evaporation reduced the temperature and increased devolatilization time. At higher temperature, NaCl tends to decompose and generates more free chlorine, producing more metal chlorides. Since Cd is a strong volatile heavy metal in MSW, the effect of moisture content on its volatilization is less than that of Pb, Zn or Cu during the MSW incineration.展开更多
Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in Chi...Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR (Community Bureau of Reference) sequential extraction procedure. The sludges contained considerable amounts of organic matter (31.8%- 48.0%), total N (16.3-26.4 g kg^-1) and total P (15.1-23.9 g kg^-1), indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China's control standards for pollutants in sludges from agricultural use (GB 4284-1984). The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.展开更多
The biosorption of copper(Ⅱ) ions onto biofilm was studied in a batch system with respect to the temperature, initial pH value and biofilm sorbent mass. The biomass exhibited the highest copper(Ⅱ) sorption capacity ...The biosorption of copper(Ⅱ) ions onto biofilm was studied in a batch system with respect to the temperature, initial pH value and biofilm sorbent mass. The biomass exhibited the highest copper(Ⅱ) sorption capacity under the conditions of room temperature, initial pH value of 6.0 and the sorbent mass 8 g. The experimental data were analyzed using four sorption kinetic models, the pseudo-first order, the Ritchie second order, the modified second order and the Elovich equations to determine the best-fit equation for the sorption of metal ions onto biofilm. Comparing with the sum of squared-errors, the results show that both the Ritchie second order and modified second order equations can fit the experimental data very well.展开更多
Heavy metals pollution in Jiaozhou Bay was studied in Ruditapes. philippinarum, a bioindicator of seawater pollution. Heavy metals in soda industry wastes “white mud” were also studied. Comparison of microwave diges...Heavy metals pollution in Jiaozhou Bay was studied in Ruditapes. philippinarum, a bioindicator of seawater pollution. Heavy metals in soda industry wastes “white mud” were also studied. Comparison of microwave digestion method with general digestion method revealed that microwave digestion is superior to general digestion in precision, recovery, digestion speed and efficiency, etc. Cd concentration in Hongdao R. philippinarum samples exceeded the national standard by 0.046 mg/kg, that of Yinghai sample by 0.02 mg/kg, and that of Hongshiya sample by 0.22 mg/kg. Sample Pb concentration in Hongshiya was found to exceed the national standard by 0.02 mg/kg. However the heavy metals concentration in R. philippinarum near the Qingdao Alkaline Factory was complied with the standard. This was proved by Penaeus chinensis culture experiment. Therefore, the possible contamination source may come from other land areas.展开更多
The process of adsorption of metal ions by immobilized marine algae with the existence of clay was investigated. It can be noted from the results that, after mixing with clay, the adsorption rate increases rapidly wit...The process of adsorption of metal ions by immobilized marine algae with the existence of clay was investigated. It can be noted from the results that, after mixing with clay, the adsorption rate increases rapidly with the increasing amount of the marine algae. When pH=5, the best ratio between the clay and the marine algae is 1:4 for Pb2+. The result of in situ handling of the waste water containing heavy metals shows that the average adsorption rates of heavy metal irons Cu2+, Cd2+, Pb2+ and Ni2+ are all over 70 %.展开更多
The aim of the present work is to remove heavy metals (copper, manganese, and zinc) from industrial wastewater of Baiji refinery using GAC (granular activated carbon). The most important factors affecting adsorpti...The aim of the present work is to remove heavy metals (copper, manganese, and zinc) from industrial wastewater of Baiji refinery using GAC (granular activated carbon). The most important factors affecting adsorption process have been studied, which are granular activated carbon thickness, H, inlet pollutant concentration, Cv, and liquid hourly space velocity, LHSV. All experiments were performed under constant temperature at 25℃ and pH = 7. The experimental apparatus was designed and constructed to enable controlling of the operating conditions. Employing five levels for each of H and LHSV and three levels for Co required 75 runs for each metal. Box-Wilson method was used to reduce the number of experiments to 15 for each metal. The results indicated that copper, manganese, and zinc can be completely removed from wastewater using activated carbon. However, breakthrough time for zinc is low. It is also shown that breakthrough time (TB) and exhaustion time (TE) are inversely proportional with pollutant concentration and LHSV (liquid hour space velocity) while it is directly proportional with the thickness of activated carbon column.展开更多
In order to optimize monitoring points and monitoring factor, the relationshipbetween pollutants and soil sample were established by correspondence analysis.Thestudy results show that the reflecting monitoring points ...In order to optimize monitoring points and monitoring factor, the relationshipbetween pollutants and soil sample were established by correspondence analysis.Thestudy results show that the reflecting monitoring points and monitoring factors in thegraphic on the same factor axis can clearly express the intrinsic link between pollutantsand monitoring points and distribution characteristics.To determine the main monitoringpoint and the main monitoring indicators can reduce and optimize the number of monitoringpoints under the premise of ensuring the typical and representative of monitoring data.Using the correlation of pollutants can reduce the number of monitoring indicators and improvethe effectiveness of data collection.展开更多
基金Project(2012BAC12B02)supported by the National Key Technology R&D Program of ChinaProject(2014FJ1011)supported by the Key Projects of Science and Technology of Hunan Province,ChinaProject(2011AA061001)supported by the National High-tech Research and Development Program of China
文摘A new process for utilization of hazardous lead-bearing wastes and iron-rich wastes by reducing-matting smelting has been developed.The slag(SG) and the iron-rich matte(IRM) are the main by-products from reducing-matting smelting of lead-bearing wastes and iron-rich wastes.The environmental risk of heavy metals(Cd,Zn,Pb and As) in the main by-products versus the charging material for reducing-matting smelting(CM) has been systematically assessed using leaching toxicity test,the three-stage sequential extraction procedure of European Community Bureau of Reference(BCR) and Hakanson Potential Ecological Risk Index Method(PERI).The results demonstrate that the ecological risk level of heavy metals for SG and IRM is significantly reduced after the reducing-matting smelting process compared with that for CM.
基金Project(51674305)supported by the National Natural Science Foundation of ChinaProject(2013WK2007)supported by the Key Project of Science and Technology of Hunan Province,China+1 种基金Project(2015CX001)supported by the Innovation Stimulating Program of Central South University,ChinaKey Project(1602FKDC007)supported by Science and Technology Program of Gansu Province,China
文摘Mg2+ and PO43+ were added into the synthetic wastewater, leading to the dissociation of the complex ions in the wastewater, and resulting in removal of copper and ammonia therein. The effects of agents addition amount, pH, and reaction time on the removal efficiency of copper and ammonia were investigated. In particular, two-sectional struvite formation (TSSF) process was established for copper and ammonia removal. MgCl2 and Na2HPO4 were added by following 90% addition in the first section and remained 10% in the second during the TSSF process. Compared with one sectional struvite formation, TSSF possessed much better performance. Under condition of n(NH3-N):n(Mg):n(P)=1:1.2:1.5 (molar ratio), pH=9, and reaction time of 30 min, the removal efficiencies of copper and ammonia were 98.9% and 99.96%, respectively. The enhanced performance of TSSF is explained by the competition of ammonia by copper?ammonia complexes and struvite. The dissociation of copper-ammonia complexes is further demonstrated by thermodynamic equilibrium analysis, on the basis of calculations and establishment of predominance phases diagram. Moreover, XRD and EDS analyses further confirmed the formation of struvite and precipitation of copper, which prove the transmission of copper and ammonia from liquid phase into solid phase.
基金Supported by Soil Improvement and Fertilizer Management for Organic Farming in Sand Areas in Nanjing Municipality(20130115)In situ Chicken Droppings Compositing-based Deodorization and Factory Environment Optimization Technology Research(KJCX20151205)~~
文摘The author summarized the advantages and potential risks of urban-rural organic wastes agricultural reutilization to reduce the potential risks of urban-rural organic wastes agricultural utilization. The results showed that: the organic wastes generated in urban-rural life as fertilizer applied into farmland made an impact on soil properties, then indirectly affected the soil microbial biomass and soil enzymes activities. In addition, the heavy metals in organic wastes would accumulate in the soil and damage to soil environment. Therefore, it was necessary to make a long- term research on the environment of soil which agricultural utilized of wastes.
基金Project supported by the National Key Basic Research Support Foundation of China (No.2004CB418503).
文摘Soil samples were collected from Zhangshi Wastewater Irrigation Area in the suburb of Shenyang City,China,an area with a 30-year irrigation history with heavy metal-containing wastewater.The chemical properties and microbial characteristics of the soils were examined to evaluate the present situation of heavy metal pollution and to assess the soil microbial characteristics under long-term heavy metal stress.In light of the National Environmental Quality Standards of China,the soil in the test area was heavily polluted by Cd and to a lesser degree by Zn and Cu,even though wastewater irrigation ceased in 1993.Soil metabolic quotient (qCO_2) had a significant positive correlation,while soil microbial quotient (qM) had a negative correlation with content of soil heavy metals.Soil microbial biomass carbon (MBC) had significantly negative correlation with Cd,but soil substrate-induced respiration (SIR),dehydrogenase activity (DHA),cellulase activity, and culturable microbial populations had no persistent correlations with soil heavy metal content.Soil nutrients,except for phosphorous,showed positive effects on soil microbial characteristics,which to a certain degree obscured the adverse effects of soil heavy metals.Soil Cd contributed more to the soil microbial characteristics,but qM and qCO_2 were more sensitive and showed persistent responses to heavy metals stress.It could be concluded that qM and qCO_2 can be used as bioindicators of heavy metal pollution in soils.
基金Supported by the National Basic Research Program of China (2011CB201502)
文摘The effect of moisture in municipal solid waste (MSW) on partitioning of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) was studied in a laboratory tubular furnace by using simulated MSW. The moisture in MSW influences heavy metals in following ways, to increase the moisture in flue gas and decrease the combustion temperature, to prolong the combustion time, and to prolong the releasing time of volatiles with the furnace temperature decreased by increasing the moisture. The volatilization of Pb, Zn and Cd was enhanced by increasing the moisture in MSW because of the prolonged combustion time. For Pb and Zn, the combustion time was important at higher temperature, while for Cd, it was important at low temperature. The moisture content showed slight effect on Cu partitioning. When extra chlorine was added to MSW, such as 1%PVC + 0.5%NaCl, the volatilization of Pb, Zn and Cu was enhanced by increasing the moisture because water evaporation reduced the temperature and increased devolatilization time. At higher temperature, NaCl tends to decompose and generates more free chlorine, producing more metal chlorides. Since Cd is a strong volatile heavy metal in MSW, the effect of moisture content on its volatilization is less than that of Pb, Zn or Cu during the MSW incineration.
基金Project supported by the National Key Basic Research Support Foundation of China (No. 2002CB412303)the Natural Science Foundation of Jiangsu Province (No. KB2004115)
文摘Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR (Community Bureau of Reference) sequential extraction procedure. The sludges contained considerable amounts of organic matter (31.8%- 48.0%), total N (16.3-26.4 g kg^-1) and total P (15.1-23.9 g kg^-1), indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China's control standards for pollutants in sludges from agricultural use (GB 4284-1984). The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.
文摘The biosorption of copper(Ⅱ) ions onto biofilm was studied in a batch system with respect to the temperature, initial pH value and biofilm sorbent mass. The biomass exhibited the highest copper(Ⅱ) sorption capacity under the conditions of room temperature, initial pH value of 6.0 and the sorbent mass 8 g. The experimental data were analyzed using four sorption kinetic models, the pseudo-first order, the Ritchie second order, the modified second order and the Elovich equations to determine the best-fit equation for the sorption of metal ions onto biofilm. Comparing with the sum of squared-errors, the results show that both the Ritchie second order and modified second order equations can fit the experimental data very well.
基金This study is supported by Project 973 (NO.2002CB412402), and key project of the Chinese Academy of Sciences (Grant NO.KJCX315W-215).
文摘Heavy metals pollution in Jiaozhou Bay was studied in Ruditapes. philippinarum, a bioindicator of seawater pollution. Heavy metals in soda industry wastes “white mud” were also studied. Comparison of microwave digestion method with general digestion method revealed that microwave digestion is superior to general digestion in precision, recovery, digestion speed and efficiency, etc. Cd concentration in Hongdao R. philippinarum samples exceeded the national standard by 0.046 mg/kg, that of Yinghai sample by 0.02 mg/kg, and that of Hongshiya sample by 0.22 mg/kg. Sample Pb concentration in Hongshiya was found to exceed the national standard by 0.02 mg/kg. However the heavy metals concentration in R. philippinarum near the Qingdao Alkaline Factory was complied with the standard. This was proved by Penaeus chinensis culture experiment. Therefore, the possible contamination source may come from other land areas.
文摘The process of adsorption of metal ions by immobilized marine algae with the existence of clay was investigated. It can be noted from the results that, after mixing with clay, the adsorption rate increases rapidly with the increasing amount of the marine algae. When pH=5, the best ratio between the clay and the marine algae is 1:4 for Pb2+. The result of in situ handling of the waste water containing heavy metals shows that the average adsorption rates of heavy metal irons Cu2+, Cd2+, Pb2+ and Ni2+ are all over 70 %.
文摘The aim of the present work is to remove heavy metals (copper, manganese, and zinc) from industrial wastewater of Baiji refinery using GAC (granular activated carbon). The most important factors affecting adsorption process have been studied, which are granular activated carbon thickness, H, inlet pollutant concentration, Cv, and liquid hourly space velocity, LHSV. All experiments were performed under constant temperature at 25℃ and pH = 7. The experimental apparatus was designed and constructed to enable controlling of the operating conditions. Employing five levels for each of H and LHSV and three levels for Co required 75 runs for each metal. Box-Wilson method was used to reduce the number of experiments to 15 for each metal. The results indicated that copper, manganese, and zinc can be completely removed from wastewater using activated carbon. However, breakthrough time for zinc is low. It is also shown that breakthrough time (TB) and exhaustion time (TE) are inversely proportional with pollutant concentration and LHSV (liquid hour space velocity) while it is directly proportional with the thickness of activated carbon column.
基金Supported by the Public Welfare Research Program of State Environmental Protection Administration(200909065)
文摘In order to optimize monitoring points and monitoring factor, the relationshipbetween pollutants and soil sample were established by correspondence analysis.Thestudy results show that the reflecting monitoring points and monitoring factors in thegraphic on the same factor axis can clearly express the intrinsic link between pollutantsand monitoring points and distribution characteristics.To determine the main monitoringpoint and the main monitoring indicators can reduce and optimize the number of monitoringpoints under the premise of ensuring the typical and representative of monitoring data.Using the correlation of pollutants can reduce the number of monitoring indicators and improvethe effectiveness of data collection.