An improved configuration of the membrane stack was adopted in the electrodeionization （EDI） cell to prevent precipitation of bivalent metal hydroxide during the running. The operational parameters that influenced t...An improved configuration of the membrane stack was adopted in the electrodeionization （EDI） cell to prevent precipitation of bivalent metal hydroxide during the running. The operational parameters that influenced the removal of copper ions from the dilute solution were optimized. The result showed that a moderate decrease in the inlet pH value and a moderate increase in the applied voltage could achieve a better removal effect. The steady process of electroplating wastewater treatment could be achieved with a removal efficiency of more than 99.5% and an enrichment factor of 5-14. The concentration of copper in purified water was less than 0.23 mg/L. This demonstrated the applicability of recovering heavy metal ions and purified water from electroplating effluent for industrial reuse.展开更多
A method to model small-scale ambient concentrations of N, N-dimethylformamide (DMF) in a synthetic leather industrial zone was developed. Longwan, a district of Wenzhou City in Southeast China, was selected as the st...A method to model small-scale ambient concentrations of N, N-dimethylformamide (DMF) in a synthetic leather industrial zone was developed. Longwan, a district of Wenzhou City in Southeast China, was selected as the study area. DMF emissions at the synthetic leather industrial zone were inventoried, during 2007, and an AMS/EPA regulatory model (AERMOD) was used to simulate DMF concentrations using 10 000 100 m×100 m grids for the 2006 period. In 2007, actual DMF concentrations were recorded at seven DMF monitoring stations, and were compared with simulated results for the same timeframe. Simulated DMF concentrations were predicted to be in the range of 0.012-2.31 mg/m3, which is similar to the range of the monitored dataset results. A large majority (93%) of relative errors (REs) between simulated and monitored concentrations ranged from 0.48% to 189.4%. While DMF emissions within factories did not exceed the regulated emission limit, simulations indicated that, in 2006, 20% of the daily average ambient DMF concentrations exceeded this limit. This Modelling method could be applied in evaluating regional atmospheric environmental capacities and human exposure to DMF.展开更多
Population exposure to pollutants is important for studies on the exposure-response relationship. However, it is difficult to evaluate population exposure to non-conventional pollutants due to limited data on concentr...Population exposure to pollutants is important for studies on the exposure-response relationship. However, it is difficult to evaluate population exposure to non-conventional pollutants due to limited data on concentration levels and the movement patterns of inhabitants. In this study, an air dispersion model was used to simulate N, N-dimethylformarnide （DMF） concentrations, as a proxy to monitoring concentrations. A total of 1289 randomly selected household representatives were surveyed to obtain information on movement characteristics. Subsequently, population movement patterns were combined with DMF concentration levels on maps of 100 m× 100 m resolution to calculate population exposure. During 2008, the estimated population exposure to DMF ranged from 0.002 to 0.64 mg/m^3. The highest level of population exposure to DMF was found in the north and northwest sub-districts of the study area, ranging from 0.42 to 0.64 mg/m^3. The population exposure to DMF for different occupational groups indicated that retired people and farmers were vulnerable subpopulations among people highly exposed to DME This was mainly because they spent most time at home where the DMF concentration was high. As pollutant concentrations were divided into small grids, we found that exposure levels were substantially impacted by population movement characteristics.展开更多
基金Project (No. Z505060) supported by the Natural Science Foundation of Zhejiang Province, China
文摘An improved configuration of the membrane stack was adopted in the electrodeionization （EDI） cell to prevent precipitation of bivalent metal hydroxide during the running. The operational parameters that influenced the removal of copper ions from the dilute solution were optimized. The result showed that a moderate decrease in the inlet pH value and a moderate increase in the applied voltage could achieve a better removal effect. The steady process of electroplating wastewater treatment could be achieved with a removal efficiency of more than 99.5% and an enrichment factor of 5-14. The concentration of copper in purified water was less than 0.23 mg/L. This demonstrated the applicability of recovering heavy metal ions and purified water from electroplating effluent for industrial reuse.
基金Project (No. 200809103) supported by the "State Environmental Protection Commonweal Trade Scientific Research" Project of Ministry of Environmental Protection of China
文摘A method to model small-scale ambient concentrations of N, N-dimethylformamide (DMF) in a synthetic leather industrial zone was developed. Longwan, a district of Wenzhou City in Southeast China, was selected as the study area. DMF emissions at the synthetic leather industrial zone were inventoried, during 2007, and an AMS/EPA regulatory model (AERMOD) was used to simulate DMF concentrations using 10 000 100 m×100 m grids for the 2006 period. In 2007, actual DMF concentrations were recorded at seven DMF monitoring stations, and were compared with simulated results for the same timeframe. Simulated DMF concentrations were predicted to be in the range of 0.012-2.31 mg/m3, which is similar to the range of the monitored dataset results. A large majority (93%) of relative errors (REs) between simulated and monitored concentrations ranged from 0.48% to 189.4%. While DMF emissions within factories did not exceed the regulated emission limit, simulations indicated that, in 2006, 20% of the daily average ambient DMF concentrations exceeded this limit. This Modelling method could be applied in evaluating regional atmospheric environmental capacities and human exposure to DMF.
基金Project (No. 200809103) supported by the State Environmental Protection Commonweal Trade Scientific Research of Ministry of Environmental Protection of China
文摘Population exposure to pollutants is important for studies on the exposure-response relationship. However, it is difficult to evaluate population exposure to non-conventional pollutants due to limited data on concentration levels and the movement patterns of inhabitants. In this study, an air dispersion model was used to simulate N, N-dimethylformarnide （DMF） concentrations, as a proxy to monitoring concentrations. A total of 1289 randomly selected household representatives were surveyed to obtain information on movement characteristics. Subsequently, population movement patterns were combined with DMF concentration levels on maps of 100 m× 100 m resolution to calculate population exposure. During 2008, the estimated population exposure to DMF ranged from 0.002 to 0.64 mg/m^3. The highest level of population exposure to DMF was found in the north and northwest sub-districts of the study area, ranging from 0.42 to 0.64 mg/m^3. The population exposure to DMF for different occupational groups indicated that retired people and farmers were vulnerable subpopulations among people highly exposed to DME This was mainly because they spent most time at home where the DMF concentration was high. As pollutant concentrations were divided into small grids, we found that exposure levels were substantially impacted by population movement characteristics.
