Increasing attention has been paid to air pollution control （APC） residues in China recently due to the rising proportion of waste incineration and the hazardous characteristics of the residues, among which heavy me...Increasing attention has been paid to air pollution control （APC） residues in China recently due to the rising proportion of waste incineration and the hazardous characteristics of the residues, among which heavy metal leaching toxicity plays an important role. Leaching behavior and potential risk of Pb and Zn in the APC residues from a Shanghai municipal solid waste （MSW） incinerator was studied, based on the leaching tests under different conditions and theoretical calculation using a geochemical thermodynamic equilibrium model MINTEQA2. Results showed that, extractant species and liquid to solid （L/S） ratio predominantly controlled the leaching toxicity of Pb and Zn, while ionic strength, vibration method and leaching time had less effect on the metals release. Leachate/final pH determined the metal leaching behavior, which changed the speciation of heavy metals in the extraction system. The equilibrium aqueous speciation, precipitation-dissolution of Pb and Zn was investigated according to the model computation, which was well in agreement with the experimental results.展开更多
This paper proposes a computational fluid dynamics(CFD)model,along with dimensionless quantitative assessment standard—air pollution residual time(APRT)for the evaluation of local haze-fog(HF)dispersion in a built en...This paper proposes a computational fluid dynamics(CFD)model,along with dimensionless quantitative assessment standard—air pollution residual time(APRT)for the evaluation of local haze-fog(HF)dispersion in a built environment.A low APRT value ensures good ventilation.A building group model that comprises high-rise business building,mid-rise office buildings,low-mid-rise residential buildings(at the center of the building group),a mid-rise recreational center,and a local road(open terrain),was scaled down(1:100)to simulate the HF dispersion process.The orientation of the building group was numerically modified to generate a wind incidence normal to the high-rise building,mid-rise buildings,recreational center,and road.The results showed that the orientation of the building group largely determines the APRT.The most favorable orientation can reduce APRT by more than 50%.Our results strongly suggested that in order to reduce the consequential negative effect of air pollution,future urban designs should undergo a comprehensive ventilation assessment to ensure a low APRT value.展开更多
基金The Key Project of Shanghai Council of Science and Technology(No. 032312043)
文摘Increasing attention has been paid to air pollution control （APC） residues in China recently due to the rising proportion of waste incineration and the hazardous characteristics of the residues, among which heavy metal leaching toxicity plays an important role. Leaching behavior and potential risk of Pb and Zn in the APC residues from a Shanghai municipal solid waste （MSW） incinerator was studied, based on the leaching tests under different conditions and theoretical calculation using a geochemical thermodynamic equilibrium model MINTEQA2. Results showed that, extractant species and liquid to solid （L/S） ratio predominantly controlled the leaching toxicity of Pb and Zn, while ionic strength, vibration method and leaching time had less effect on the metals release. Leachate/final pH determined the metal leaching behavior, which changed the speciation of heavy metals in the extraction system. The equilibrium aqueous speciation, precipitation-dissolution of Pb and Zn was investigated according to the model computation, which was well in agreement with the experimental results.
基金This research was supported by a special fund of the State Key Joint Laboratory of Environment Simulation and Pollution Control(2015)-15K09ESPCT,Tsinghua University,China。
文摘This paper proposes a computational fluid dynamics(CFD)model,along with dimensionless quantitative assessment standard—air pollution residual time(APRT)for the evaluation of local haze-fog(HF)dispersion in a built environment.A low APRT value ensures good ventilation.A building group model that comprises high-rise business building,mid-rise office buildings,low-mid-rise residential buildings(at the center of the building group),a mid-rise recreational center,and a local road(open terrain),was scaled down(1:100)to simulate the HF dispersion process.The orientation of the building group was numerically modified to generate a wind incidence normal to the high-rise building,mid-rise buildings,recreational center,and road.The results showed that the orientation of the building group largely determines the APRT.The most favorable orientation can reduce APRT by more than 50%.Our results strongly suggested that in order to reduce the consequential negative effect of air pollution,future urban designs should undergo a comprehensive ventilation assessment to ensure a low APRT value.
