Lipovtsy coal field mine №4 processed north-western reserves of Lipovtsy field in Primorski Krai (Russia). In 1997, the mine was declared unprofitable and was abandoned by natural flooding with no arrangement of mine...Lipovtsy coal field mine №4 processed north-western reserves of Lipovtsy field in Primorski Krai (Russia). In 1997, the mine was declared unprofitable and was abandoned by natural flooding with no arrangement of mine water discharge and in 2005 it was fully flooded. The main sources of pollution in the studied area are spoil heaps (mine wastes), underspoil filtering waters and mine waters which are being discharged on the surface after finishing of “hydraulic funnel” artificial support. The study of technogenic landscape of abandoned mine industrial area showed that its morphologic form is dominated by spoil heaps. Soils located near mine waste body differ from benchmark soils by chemical properties and size distribution. The influence of active hydrochemical mine and drainage water flows is the reason of the above-mentioned variation in soil properties. Results showed that, there exist a high correlation ratios between chemical composition of mine waters and water extracts from soil: Between the alkalinity of mine waters and electrical conductivity of soil water extracts (r = 0.73), between mine water iron content and pH of soil water extract (r = −0.56), between the solid residue of mine waters and electrical conductivity of soil water extracts (r = 0.72), between the mine waters calcium content and electrical conductivity of soil water extracts (r = −0.75), between the alkalinity of mine waters and silicon dioxide content of soil water extracts (r = 0.61), between the mineralization of mine waters and chrome content of soil water extracts (r = 0.73).展开更多
Total contents of heavy metals ( Pb, Cr, Cd, Hg, As, Cu, Zn, and Ni) in 68 soil samples were determined to evaluate the contamination level of soil from five coal mine areas in Xingren County, Guizhou province. The ...Total contents of heavy metals ( Pb, Cr, Cd, Hg, As, Cu, Zn, and Ni) in 68 soil samples were determined to evaluate the contamination level of soil from five coal mine areas in Xingren County, Guizhou province. The pollution levels of heavy metals were characterized by anthro- pogenic influence multiple, and the pollution of heavy metal in soil was evaluated using geo-accumulation index. Based on the health risk models recommended by the U.S. Environmental Protection Agency ( US EPA), the health risks of heavy metals in the soils were assessed. The results showed that the abandoned land in the five coal mining areas were contaminated by heavy metals, and the order of pollution levels of eight heavy metals was As 〉 Pb 〉 Cu 〉 Hg 〉 Ni 〉 Cr 〉 Cd 〉 Zn. The soils suffered moderate-heavy pollution from As and Pb, and the contents of As and Pb in the soils were 13.16 and 4.76 times higher than the background values of Guizhou Province, followed by Cu, Hg and Ni , while soil pollution from Cr, Cd and Zn was mild. The order of non-caminogenic risks of the heavy metals in the soils was As 〉 Pb 〉 Cr 〉 Ni 〉 Cu 〉 Hg 〉 Cd 〉 Zn, and the non-carcinogenic dsk value of As was higher than that its threshold value 1, which indicated that As had a high potential health risk to adults and children. The order of carcinogen risks of the four heavy metals was As 〉 Cd 〉 Cr 〉 Ni, and the carcinogenic risk value of As was higher than its threshold value, indicating that As had a high carcinogenic risk to adults and children. The carcinogenic risk values of other three heavy metals ( Cd, Cr and Ni) were lower than the threshold value, so they had no carcinogenic risk to human health. Moreover, children were more sensitively affect- ed by heavy metals from the abandoned land. Therefore, the health of children in such areas should be paid more attention to. The HI value of the eight heavy metals to children was seven times higher than that to adults. The contribution rate of HQAs to HI was about 88%, and the contribution rate of CRA, to TCR was about 98%, so As was the most crucial factor influencing non-carcinogenic and carcinogenic dsk in the abandoned soils.展开更多
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining tech...Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.展开更多
The retained coal in the end slope of an open-pit mine can be mined by the highwall mining techniques.However,the instability mechanism of the reserved rib pillar under dynamic loads of mining haul trucks and static l...The retained coal in the end slope of an open-pit mine can be mined by the highwall mining techniques.However,the instability mechanism of the reserved rib pillar under dynamic loads of mining haul trucks and static loads of the overlying strata is not clear,which restricts the safe and efcient application of highwall mining.In this study,the load-bearing model of the rib pillar in highwall mining was established,the cusp catastrophe theory and the safety coefcient of the rib pillar were considered,and the criterion equations of the rib pillar stability were proposed.Based on the limit equilibrium theory,the limit stress of the rib pillar was analyzed,and the calculation equations of plastic zone width of the rib pillar in highwall mining were obtained.Based on the Winkler foundation beam theory,the elastic foundation beam model composed of the rib pillar and roof under the highwall mining was established,and the calculation equations for the compression of the rib pillar under dynamic and static loads were developed.The results showed that with the increase of the rib pillar width,the total compression of the rib pillar under dynamic and static loads decreases nonlinearly,and the compression of the rib pillar caused by static loads of the overlying strata and trucks has a decisive role.Numerical simulation and theoretical calculation were also performed in this study.In the numerical simulation,the coal seam with a buried depth of 122 m and a thickness of 3 m is mined by highwall mining techniques.According to the established rib pillar instability model of the highwall mining system,it is found that when the mining opening width is 3 m,the reasonable width of the rib pillar is at least 1.3 m,and the safety factor of the rib pillar is 1.3.The numerical simulation results are in good agreement with the results of theoretical calculation,which verifes the feasibility of the theoretical analysis of the rib pillar stability.This research provides a reference for the stability analysis of rib pillars under highwall mining.展开更多
Mining activities produced a lot of abandoned mine land. This paper introduced the theoretical and technical progress of ecological restoration of surface coal mines, mining subsidence land and coal waste piles in Chi...Mining activities produced a lot of abandoned mine land. This paper introduced the theoretical and technical progress of ecological restoration of surface coal mines, mining subsidence land and coal waste piles in China and discussed some key problems for research in the future. Ecological restoration of abandoned mine land was related to many disciplines, and multi-disciplinary theories might make great contributes to it. Some practical techniques of ecological restoration of abandoned mine land and their demonstration bases in China were introduced. Ecosystem succession process and mechanism, structure optimization of land use and new technologies of ecological restoration of abandoned mine land should be focused on in research activities.展开更多
面向“30·60”双碳目标,矿区能源利用方式的绿色、经济、高效转型成为我国能源革命的迫切需求。西部矿区拥有丰富的可再生能源资源禀赋,但仍面临着可再生能源就地消纳困难,电力设备投资成本高、利用率低以及外送输电通道有限的困...面向“30·60”双碳目标,矿区能源利用方式的绿色、经济、高效转型成为我国能源革命的迫切需求。西部矿区拥有丰富的可再生能源资源禀赋,但仍面临着可再生能源就地消纳困难,电力设备投资成本高、利用率低以及外送输电通道有限的困难。为提升矿区用能清洁化程度,提升矿区能源供给的稳定性与可靠性,增强矿区对外部电网的支撑能力,提出全清洁能源下的高品质矿区能源系统(High-quality Coal Mine Energy System,HCMES)及其配置优化方法。首先,考虑西部矿山综合能源系统的负荷特点与伴生能源利用,结合可再生能源发电与废弃矿井抽水蓄能,构建全清洁能源下的HCMES架构。其次,考虑到矿区生产全流程负荷的需求响应能力,考虑系统的能量平衡约束,提出全清洁能源下的高品质矿区能源系统优化配置模型。最后,以系统年平均综合成本最小化为目标,将原问题转化为混合整数线性规划模型,求解生成高品质矿区能源系统优化配置方案。以我国西部某年产煤量1200万t的矿区实际数据为实例,验证所提模型与方法的有效性,并分析可再生能源出力与生产负荷需求不确定性对系统优化配置结果的影响。算例仿真设置了4种矿区能源系统配置方式:不配置储能、配置抽水蓄能、配置电化学储能、配置抽水蓄能(不外购电能)。结果表明,所提出的HCMES相较于其他配置方式可减少电气一次设备投资11.11%,相较于方式3可降低年平均综合成本7.91%,且最多可减少矿区生产用能总二氧化碳排放量91.17%。展开更多
文摘Lipovtsy coal field mine №4 processed north-western reserves of Lipovtsy field in Primorski Krai (Russia). In 1997, the mine was declared unprofitable and was abandoned by natural flooding with no arrangement of mine water discharge and in 2005 it was fully flooded. The main sources of pollution in the studied area are spoil heaps (mine wastes), underspoil filtering waters and mine waters which are being discharged on the surface after finishing of “hydraulic funnel” artificial support. The study of technogenic landscape of abandoned mine industrial area showed that its morphologic form is dominated by spoil heaps. Soils located near mine waste body differ from benchmark soils by chemical properties and size distribution. The influence of active hydrochemical mine and drainage water flows is the reason of the above-mentioned variation in soil properties. Results showed that, there exist a high correlation ratios between chemical composition of mine waters and water extracts from soil: Between the alkalinity of mine waters and electrical conductivity of soil water extracts (r = 0.73), between mine water iron content and pH of soil water extract (r = −0.56), between the solid residue of mine waters and electrical conductivity of soil water extracts (r = 0.72), between the mine waters calcium content and electrical conductivity of soil water extracts (r = −0.75), between the alkalinity of mine waters and silicon dioxide content of soil water extracts (r = 0.61), between the mineralization of mine waters and chrome content of soil water extracts (r = 0.73).
基金Supported by the National Natural Science Foundation of China(21467005)
文摘Total contents of heavy metals ( Pb, Cr, Cd, Hg, As, Cu, Zn, and Ni) in 68 soil samples were determined to evaluate the contamination level of soil from five coal mine areas in Xingren County, Guizhou province. The pollution levels of heavy metals were characterized by anthro- pogenic influence multiple, and the pollution of heavy metal in soil was evaluated using geo-accumulation index. Based on the health risk models recommended by the U.S. Environmental Protection Agency ( US EPA), the health risks of heavy metals in the soils were assessed. The results showed that the abandoned land in the five coal mining areas were contaminated by heavy metals, and the order of pollution levels of eight heavy metals was As 〉 Pb 〉 Cu 〉 Hg 〉 Ni 〉 Cr 〉 Cd 〉 Zn. The soils suffered moderate-heavy pollution from As and Pb, and the contents of As and Pb in the soils were 13.16 and 4.76 times higher than the background values of Guizhou Province, followed by Cu, Hg and Ni , while soil pollution from Cr, Cd and Zn was mild. The order of non-caminogenic risks of the heavy metals in the soils was As 〉 Pb 〉 Cr 〉 Ni 〉 Cu 〉 Hg 〉 Cd 〉 Zn, and the non-carcinogenic dsk value of As was higher than that its threshold value 1, which indicated that As had a high potential health risk to adults and children. The order of carcinogen risks of the four heavy metals was As 〉 Cd 〉 Cr 〉 Ni, and the carcinogenic risk value of As was higher than its threshold value, indicating that As had a high carcinogenic risk to adults and children. The carcinogenic risk values of other three heavy metals ( Cd, Cr and Ni) were lower than the threshold value, so they had no carcinogenic risk to human health. Moreover, children were more sensitively affect- ed by heavy metals from the abandoned land. Therefore, the health of children in such areas should be paid more attention to. The HI value of the eight heavy metals to children was seven times higher than that to adults. The contribution rate of HQAs to HI was about 88%, and the contribution rate of CRA, to TCR was about 98%, so As was the most crucial factor influencing non-carcinogenic and carcinogenic dsk in the abandoned soils.
文摘Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.
基金fnancially supported by National Natural Science Foundation of China(Grant No.51974295).
文摘The retained coal in the end slope of an open-pit mine can be mined by the highwall mining techniques.However,the instability mechanism of the reserved rib pillar under dynamic loads of mining haul trucks and static loads of the overlying strata is not clear,which restricts the safe and efcient application of highwall mining.In this study,the load-bearing model of the rib pillar in highwall mining was established,the cusp catastrophe theory and the safety coefcient of the rib pillar were considered,and the criterion equations of the rib pillar stability were proposed.Based on the limit equilibrium theory,the limit stress of the rib pillar was analyzed,and the calculation equations of plastic zone width of the rib pillar in highwall mining were obtained.Based on the Winkler foundation beam theory,the elastic foundation beam model composed of the rib pillar and roof under the highwall mining was established,and the calculation equations for the compression of the rib pillar under dynamic and static loads were developed.The results showed that with the increase of the rib pillar width,the total compression of the rib pillar under dynamic and static loads decreases nonlinearly,and the compression of the rib pillar caused by static loads of the overlying strata and trucks has a decisive role.Numerical simulation and theoretical calculation were also performed in this study.In the numerical simulation,the coal seam with a buried depth of 122 m and a thickness of 3 m is mined by highwall mining techniques.According to the established rib pillar instability model of the highwall mining system,it is found that when the mining opening width is 3 m,the reasonable width of the rib pillar is at least 1.3 m,and the safety factor of the rib pillar is 1.3.The numerical simulation results are in good agreement with the results of theoretical calculation,which verifes the feasibility of the theoretical analysis of the rib pillar stability.This research provides a reference for the stability analysis of rib pillars under highwall mining.
基金National Twelve Five-year Plan Science and Technology Program (2012BAC04B03).
文摘Mining activities produced a lot of abandoned mine land. This paper introduced the theoretical and technical progress of ecological restoration of surface coal mines, mining subsidence land and coal waste piles in China and discussed some key problems for research in the future. Ecological restoration of abandoned mine land was related to many disciplines, and multi-disciplinary theories might make great contributes to it. Some practical techniques of ecological restoration of abandoned mine land and their demonstration bases in China were introduced. Ecosystem succession process and mechanism, structure optimization of land use and new technologies of ecological restoration of abandoned mine land should be focused on in research activities.
文摘面向“30·60”双碳目标,矿区能源利用方式的绿色、经济、高效转型成为我国能源革命的迫切需求。西部矿区拥有丰富的可再生能源资源禀赋,但仍面临着可再生能源就地消纳困难,电力设备投资成本高、利用率低以及外送输电通道有限的困难。为提升矿区用能清洁化程度,提升矿区能源供给的稳定性与可靠性,增强矿区对外部电网的支撑能力,提出全清洁能源下的高品质矿区能源系统(High-quality Coal Mine Energy System,HCMES)及其配置优化方法。首先,考虑西部矿山综合能源系统的负荷特点与伴生能源利用,结合可再生能源发电与废弃矿井抽水蓄能,构建全清洁能源下的HCMES架构。其次,考虑到矿区生产全流程负荷的需求响应能力,考虑系统的能量平衡约束,提出全清洁能源下的高品质矿区能源系统优化配置模型。最后,以系统年平均综合成本最小化为目标,将原问题转化为混合整数线性规划模型,求解生成高品质矿区能源系统优化配置方案。以我国西部某年产煤量1200万t的矿区实际数据为实例,验证所提模型与方法的有效性,并分析可再生能源出力与生产负荷需求不确定性对系统优化配置结果的影响。算例仿真设置了4种矿区能源系统配置方式:不配置储能、配置抽水蓄能、配置电化学储能、配置抽水蓄能(不外购电能)。结果表明,所提出的HCMES相较于其他配置方式可减少电气一次设备投资11.11%,相较于方式3可降低年平均综合成本7.91%,且最多可减少矿区生产用能总二氧化碳排放量91.17%。