A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the i...A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surrounding rock mass. The effect of the regional hydraulic gradient was also investigated. The analyses were conducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material(i.e., water retention curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.展开更多
Unmanned aerial vehicle has low cost, good flexibility, low risk and high efficiency. When it is applied in maritime supervision, such as maritime patrol, sea cruise, investigation and emergency response, maritime sea...Unmanned aerial vehicle has low cost, good flexibility, low risk and high efficiency. When it is applied in maritime supervision, such as maritime patrol, sea cruise, investigation and emergency response, maritime search and rescue, navigation channel measurement, monitoring and inspection of the oil and sewage spills from ships at sea, it can effectively expand the uses of monitoring sea areas, reduce the phenomenon of illegal use of sea, which can improve modernization construction in maritime supervision. According to the UAV (unmanned aerial vehicle) development and application, this paper explores the advantages of the UAV application in maritime adminstration, as well as the characteristics of maritime adminstration, put forward some countermeasures and suggestions of UAV applied in maritime adminstration.展开更多
A systematic strategy for retrofit of the multi-period heat exchanger network (HEN) on the basis of the multi- objective optimization is developed. In this three-stage procedure, a simplified multi-objective optimiz...A systematic strategy for retrofit of the multi-period heat exchanger network (HEN) on the basis of the multi- objective optimization is developed. In this three-stage procedure, a simplified multi-objective optimization model of the multi-period lIEN is first established and then solved to target the retrofit, aiming to minimizing the total annual cost and total annual CO2 emissions. The obtained Pareto front represents series of retrofit targets under different emission limitations, from which the most desirable one can be selected. The matching of the existing and the required heat exchangers is further implemented to finalize the retrofit, which will meet the practical retrofit requirements and matching restrictions. The application of the proposed procedure is illustrated through a case study of a HEN in a vacuum gas oil hydro-treating unit.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
基金financial support of the Natural Sciences and Engineering Research Council of Canada (NSERC)the partners of Research Institute on Mines and the Environment (RIME UQAT-Polytechnique)
文摘A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surrounding rock mass. The effect of the regional hydraulic gradient was also investigated. The analyses were conducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material(i.e., water retention curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.
文摘Unmanned aerial vehicle has low cost, good flexibility, low risk and high efficiency. When it is applied in maritime supervision, such as maritime patrol, sea cruise, investigation and emergency response, maritime search and rescue, navigation channel measurement, monitoring and inspection of the oil and sewage spills from ships at sea, it can effectively expand the uses of monitoring sea areas, reduce the phenomenon of illegal use of sea, which can improve modernization construction in maritime supervision. According to the UAV (unmanned aerial vehicle) development and application, this paper explores the advantages of the UAV application in maritime adminstration, as well as the characteristics of maritime adminstration, put forward some countermeasures and suggestions of UAV applied in maritime adminstration.
基金Supported by the National Natural Science Foundation of China(21376188,21676211)
文摘A systematic strategy for retrofit of the multi-period heat exchanger network (HEN) on the basis of the multi- objective optimization is developed. In this three-stage procedure, a simplified multi-objective optimization model of the multi-period lIEN is first established and then solved to target the retrofit, aiming to minimizing the total annual cost and total annual CO2 emissions. The obtained Pareto front represents series of retrofit targets under different emission limitations, from which the most desirable one can be selected. The matching of the existing and the required heat exchangers is further implemented to finalize the retrofit, which will meet the practical retrofit requirements and matching restrictions. The application of the proposed procedure is illustrated through a case study of a HEN in a vacuum gas oil hydro-treating unit.
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.