The atmospheric mercury pollution in Beijing is a serious problem.Atmospheric mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemen...The atmospheric mercury pollution in Beijing is a serious problem.Atmospheric mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemental mercury,divalent mercury and particulate-phase mercury.Many studies showed that mercury in Beijing's air was higher than the general level of mercury concentration in the atmosphere.Mercury emission sources were discussed.Industrial emissions,coal burning,vehicle exhaust emissions and waste incineration were thought to be the main sources of atmospheric mercury pollution in Beijing.And also meteorology has an effect on atmospheric mercury concentration in Beijing.Measures have been taken to control the emission of mercury into the air in recent years.展开更多
To reduce carbon intensity, an improved management method balancing the reduction in costs and greenhouse gas(GHG)emissions is required for Tianjin's waste management system. Firstly, six objective functions, name...To reduce carbon intensity, an improved management method balancing the reduction in costs and greenhouse gas(GHG)emissions is required for Tianjin's waste management system. Firstly, six objective functions, namely, cost minimization, GHG minimization, eco-efficiency minimization, cost maximization, GHG maximization and eco-efficiency maximization, are built and subjected to the same constraints with each objective function corresponding to one scenario. Secondly, GHG emissions and costs are derived from the waste flow of each scenario. Thirdly, the range of GHG emissions and costs of other potential scenarios are obtained and plotted through adjusting waste flow with infinitely possible step sizes according to the correlation among the above six scenarios. And the optimal scenario is determined based on this range. The results suggest the following conclusions. 1) The scenarios located on the border between scenario cost minimization and GHG minimization create an optimum curve, and scenario GHG minimization has the smallest eco-efficiency on the curve; 2) Simple pursuit of eco-efficiency minimization using fractional programming may be unreasonable; 3) Balancing GHG emissions from incineration and landfills benefits Tianjin's waste management system as it reduces GHG emissions and costs.展开更多
Waste disposal is a major source of greenhouse gas emissions such as methane, carbon dioxide and nitrous oxide. In China, rapid economic growth and urbanization have led to increasing solid waste generation and greenh...Waste disposal is a major source of greenhouse gas emissions such as methane, carbon dioxide and nitrous oxide. In China, rapid economic growth and urbanization have led to increasing solid waste generation and greenhouse gas emissions from the waste sector. Based on the first-order decay （FOD） method recommended by the 2006 IPCC Guidelines, this paper systematically estimates China＇s carbon emissions from the waste sector and forecasts their peak. Results indicate that between 1981 and 2009, China＇s carbon emissions from the waste sector surged, possibly peaking by around 2024. In comparison with developed countries, there is a large potential to improve waste disposal in China. Industrial upgradation and waste disposal improvement will help reduce waste generation and carbon emissions from the waste sector.展开更多
文摘The atmospheric mercury pollution in Beijing is a serious problem.Atmospheric mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemental mercury,divalent mercury and particulate-phase mercury.Many studies showed that mercury in Beijing's air was higher than the general level of mercury concentration in the atmosphere.Mercury emission sources were discussed.Industrial emissions,coal burning,vehicle exhaust emissions and waste incineration were thought to be the main sources of atmospheric mercury pollution in Beijing.And also meteorology has an effect on atmospheric mercury concentration in Beijing.Measures have been taken to control the emission of mercury into the air in recent years.
基金Project(51406133) supported by the National Natural Science Foundation of ChinaProject supported by the Scientific Research Foundation for the Returned Overseas,ChinaProject supported by Independent Innovation Fund of Tianjin University,China
文摘To reduce carbon intensity, an improved management method balancing the reduction in costs and greenhouse gas(GHG)emissions is required for Tianjin's waste management system. Firstly, six objective functions, namely, cost minimization, GHG minimization, eco-efficiency minimization, cost maximization, GHG maximization and eco-efficiency maximization, are built and subjected to the same constraints with each objective function corresponding to one scenario. Secondly, GHG emissions and costs are derived from the waste flow of each scenario. Thirdly, the range of GHG emissions and costs of other potential scenarios are obtained and plotted through adjusting waste flow with infinitely possible step sizes according to the correlation among the above six scenarios. And the optimal scenario is determined based on this range. The results suggest the following conclusions. 1) The scenarios located on the border between scenario cost minimization and GHG minimization create an optimum curve, and scenario GHG minimization has the smallest eco-efficiency on the curve; 2) Simple pursuit of eco-efficiency minimization using fractional programming may be unreasonable; 3) Balancing GHG emissions from incineration and landfills benefits Tianjin's waste management system as it reduces GHG emissions and costs.
文摘Waste disposal is a major source of greenhouse gas emissions such as methane, carbon dioxide and nitrous oxide. In China, rapid economic growth and urbanization have led to increasing solid waste generation and greenhouse gas emissions from the waste sector. Based on the first-order decay （FOD） method recommended by the 2006 IPCC Guidelines, this paper systematically estimates China＇s carbon emissions from the waste sector and forecasts their peak. Results indicate that between 1981 and 2009, China＇s carbon emissions from the waste sector surged, possibly peaking by around 2024. In comparison with developed countries, there is a large potential to improve waste disposal in China. Industrial upgradation and waste disposal improvement will help reduce waste generation and carbon emissions from the waste sector.
