This paper presents the effect of open dumping of municipal solid waste(MSW) on soil characteristics in the mountainous region of Himachal Pradesh, India. The solid waste of dumpsite contains various complex character...This paper presents the effect of open dumping of municipal solid waste(MSW) on soil characteristics in the mountainous region of Himachal Pradesh, India. The solid waste of dumpsite contains various complex characteristics with organic fractions of the highest proportions. As leachate percolates into the soil, it migrates contaminants into the soil and affects soil stability and strength. The study includes the geotechnical investigation of dump soil characteristics and its comparison with the natural soil samples taken from outside the proximity of dumpsites. The geochemical analysis of dumpsite soil samples was also carried out by scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS).Visual inspection revealed that the MSW consists of high fraction of organics, followed by paper. The soil samples were collected from five trial pits in the dumpsites at depths of 0.5 m, 1 m and 1.5 m. Then the collected soil samples were subjected to specific gravity test, grain size analysis, Atterberg’s limit test,compaction test, direct shear test, California bearing ratio(CBR) test and permeability analysis. The study indicated that the dumpsite soils from four study regions show decreasing trends in the values of maximum dry density(MDD), specific gravity, cohesion and CBR, and increasing permeability as compared to the natural soil. The results show that the geotechnical properties of the soils at all four study locations have been severely hampered due to contamination induced by open dumping of waste.展开更多
Sequential fractionation of Cr, Zn, Pb and Mn in soil samples collected 5 m - 104 m away from Esisi open dump was determined to evaluate the potential health danger posed by the metals. Spatial test soil samples were ...Sequential fractionation of Cr, Zn, Pb and Mn in soil samples collected 5 m - 104 m away from Esisi open dump was determined to evaluate the potential health danger posed by the metals. Spatial test soil samples were collected at various increasing distances (5 m - 104 m) from the epicentre of the dump using a stainless steel auger. Tessier’s sequential extraction protocols were employed. The concentrations of the metals in the various fractions were determined, the fractions are exchangeable fraction, carbonate fraction, Fe-Mn oxide fraction, organic fraction and residual fraction. The metals were found mostly concentrated in the Fe-Mn oxide fraction. This study has provided information on the mobility factors and chemical forms of Cr, Zn, Pb and Mn in the soil of the environment of Esisi open dump and the environmental risk of the metals in the environment of Esisi open dump.展开更多
In Mexico, hazardous and non-hazardous urban solid wastes are commonly disposed of in dumps. Inappropriate waste disposal makes solid waste disposal sites potential sources of pollution and health risks. The objective...In Mexico, hazardous and non-hazardous urban solid wastes are commonly disposed of in dumps. Inappropriate waste disposal makes solid waste disposal sites potential sources of pollution and health risks. The objective of the present study was to evaluate the impact of leachate from a dump on surface water systems. Physical, chemical, and bacteriological characteristics and the volume of leachate were measured. The site of study is located in Zinaprcuaro, Michoac^m, Mexico, and was chosen due to the water supplies were in line with the dump, thus conforming a system to test for movement of toxins. Leachate and water from three ponds located at different distances to the dump were sampled during three months of a year to measure physicochemical and bacteriological parameters, according to the standard methods of the American Public Health Association; the concentration of heavy metals was measured by atomic absorption spectrometry. Most characteristics exceed the maximum permissible limits established for the Mexican legislation regarding wastewater discharges and drinking water. Likewise, analysis of variance showed statistically significant differences between concentrations of pollutants in relation to the distance from the dump of sampled sites and with season of sampling, thus confirming the contamination of water by dump leachate.展开更多
Based on the externality theory and the environmental value theory, the hypothesis of charging for waste dumping of open-pit metal mines was put forth. The charging methods were designed according to the characteristi...Based on the externality theory and the environmental value theory, the hypothesis of charging for waste dumping of open-pit metal mines was put forth. The charging methods were designed according to the characteristics of waste dumping of openpit metal mines, including charging based on the dumping amount of the total waste, multi-charging factors, exceeding standard punishment charging, and so on. The main charging parameter is based on the dumping area rather than the total amount of waste dumping. The charging model of waste dumping of open-pit mines was formulated, and the charging rate was divided into two parts, i.e., the standard charging rate and the differential charging rate. The standard charging rate was derived using the equilibrium dynamic model, whereas the differential one was obtained by establishing the fuzzy synthesized evaluation model.展开更多
In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase ...In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase capacity of the dump in future. This paper describes current condition of waste dump of Narynsukhait coal mine and then discusses the optimization of waste dump geometry by analyzing the effect of different waste dump’s bench configuration on slope performance. Optimization of the geometry is carried out by investigating and comparing the performance of geometrical combinations of bench height, bench angles and number of safety berm by means of numerical modeling. The model shows that increasing height of bench is able to induce shear stress in the bench and may initiate bench instable. However, the shear stress can be limited by having safety berm and/or reducing bench angle to satisfy the stability criteria.展开更多
Dumping areas represent a stable hazard. To clarify the formation mechanism of dumping piles on dumping area stability, an investigation in open pit mine was performed. Moreover, experiments with gravel were conducted...Dumping areas represent a stable hazard. To clarify the formation mechanism of dumping piles on dumping area stability, an investigation in open pit mine was performed. Moreover, experiments with gravel were conducted based on the research site conditions. The geological conditions, dumping operation, and waste particle size distribution were investigated in the Heidaigou open pit mine. Particle size distribution, dumping height, dumping volume, and floor inclination were varied to examine their effects on a single pile formation. The design of blasting can be modified to make the particle size of waste smaller. The volume of the bucket does not have a pronounced effect on dumping pile repose angle, capacity of dumping pile, and dumping area stability. The smaller the floor inclination, the better it is. Two measures are proposed to increase the kinetic force of friction between waste material and floor surface. The interval distance, dumping volume and dumping height were also varied to examine the interaction between the formations of multiple piles. The dumping width should be decided through optimization efficiency of bulldozer and dumping device in bucket wheel excavator-belt-stacker dumping operation and dragline dumping operation. Moreover, the volume of the bucket does not have a pronounced interaction effect. In the dumping operation, the work amount of bulldozer decreases as dumping pile increases. The design of the dumping operation must consider the total efficiency of ground leveling operation and forming dumping the area.展开更多
According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport p...According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport passage is analyzed in aspects such as the internal dump occupation,dragline operation efficiency,coal transport distance,upper stripping distance and shifting quantities.The middle passage should be given priority in thick overburden open pit mine because the dragline system is only responsible for part stripping task.According to characteristics of middle passage,the transport passage is divided into parallel climbing,vertical climbing and horizontal transport.In addition,the transport passage structure optimization model and shifting distance optimization model are established in this paper.The case study in Heidaigou open pit mine shows that,the parallel climbing height is accounted for about 60%of the total height,and reasonable shifting distances of the first mining area and the second mining area are 240 and 320 m.Sensitivity analysis shows that,the total passage height has important influence on the shifting step,so it is with the stripping height and passage construction cost to the passage structure.展开更多
文摘This paper presents the effect of open dumping of municipal solid waste(MSW) on soil characteristics in the mountainous region of Himachal Pradesh, India. The solid waste of dumpsite contains various complex characteristics with organic fractions of the highest proportions. As leachate percolates into the soil, it migrates contaminants into the soil and affects soil stability and strength. The study includes the geotechnical investigation of dump soil characteristics and its comparison with the natural soil samples taken from outside the proximity of dumpsites. The geochemical analysis of dumpsite soil samples was also carried out by scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS).Visual inspection revealed that the MSW consists of high fraction of organics, followed by paper. The soil samples were collected from five trial pits in the dumpsites at depths of 0.5 m, 1 m and 1.5 m. Then the collected soil samples were subjected to specific gravity test, grain size analysis, Atterberg’s limit test,compaction test, direct shear test, California bearing ratio(CBR) test and permeability analysis. The study indicated that the dumpsite soils from four study regions show decreasing trends in the values of maximum dry density(MDD), specific gravity, cohesion and CBR, and increasing permeability as compared to the natural soil. The results show that the geotechnical properties of the soils at all four study locations have been severely hampered due to contamination induced by open dumping of waste.
文摘Sequential fractionation of Cr, Zn, Pb and Mn in soil samples collected 5 m - 104 m away from Esisi open dump was determined to evaluate the potential health danger posed by the metals. Spatial test soil samples were collected at various increasing distances (5 m - 104 m) from the epicentre of the dump using a stainless steel auger. Tessier’s sequential extraction protocols were employed. The concentrations of the metals in the various fractions were determined, the fractions are exchangeable fraction, carbonate fraction, Fe-Mn oxide fraction, organic fraction and residual fraction. The metals were found mostly concentrated in the Fe-Mn oxide fraction. This study has provided information on the mobility factors and chemical forms of Cr, Zn, Pb and Mn in the soil of the environment of Esisi open dump and the environmental risk of the metals in the environment of Esisi open dump.
文摘In Mexico, hazardous and non-hazardous urban solid wastes are commonly disposed of in dumps. Inappropriate waste disposal makes solid waste disposal sites potential sources of pollution and health risks. The objective of the present study was to evaluate the impact of leachate from a dump on surface water systems. Physical, chemical, and bacteriological characteristics and the volume of leachate were measured. The site of study is located in Zinaprcuaro, Michoac^m, Mexico, and was chosen due to the water supplies were in line with the dump, thus conforming a system to test for movement of toxins. Leachate and water from three ponds located at different distances to the dump were sampled during three months of a year to measure physicochemical and bacteriological parameters, according to the standard methods of the American Public Health Association; the concentration of heavy metals was measured by atomic absorption spectrometry. Most characteristics exceed the maximum permissible limits established for the Mexican legislation regarding wastewater discharges and drinking water. Likewise, analysis of variance showed statistically significant differences between concentrations of pollutants in relation to the distance from the dump of sampled sites and with season of sampling, thus confirming the contamination of water by dump leachate.
文摘Based on the externality theory and the environmental value theory, the hypothesis of charging for waste dumping of open-pit metal mines was put forth. The charging methods were designed according to the characteristics of waste dumping of openpit metal mines, including charging based on the dumping amount of the total waste, multi-charging factors, exceeding standard punishment charging, and so on. The main charging parameter is based on the dumping area rather than the total amount of waste dumping. The charging model of waste dumping of open-pit mines was formulated, and the charging rate was divided into two parts, i.e., the standard charging rate and the differential charging rate. The standard charging rate was derived using the equilibrium dynamic model, whereas the differential one was obtained by establishing the fuzzy synthesized evaluation model.
文摘In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase capacity of the dump in future. This paper describes current condition of waste dump of Narynsukhait coal mine and then discusses the optimization of waste dump geometry by analyzing the effect of different waste dump’s bench configuration on slope performance. Optimization of the geometry is carried out by investigating and comparing the performance of geometrical combinations of bench height, bench angles and number of safety berm by means of numerical modeling. The model shows that increasing height of bench is able to induce shear stress in the bench and may initiate bench instable. However, the shear stress can be limited by having safety berm and/or reducing bench angle to satisfy the stability criteria.
文摘Dumping areas represent a stable hazard. To clarify the formation mechanism of dumping piles on dumping area stability, an investigation in open pit mine was performed. Moreover, experiments with gravel were conducted based on the research site conditions. The geological conditions, dumping operation, and waste particle size distribution were investigated in the Heidaigou open pit mine. Particle size distribution, dumping height, dumping volume, and floor inclination were varied to examine their effects on a single pile formation. The design of blasting can be modified to make the particle size of waste smaller. The volume of the bucket does not have a pronounced effect on dumping pile repose angle, capacity of dumping pile, and dumping area stability. The smaller the floor inclination, the better it is. Two measures are proposed to increase the kinetic force of friction between waste material and floor surface. The interval distance, dumping volume and dumping height were also varied to examine the interaction between the formations of multiple piles. The dumping width should be decided through optimization efficiency of bulldozer and dumping device in bucket wheel excavator-belt-stacker dumping operation and dragline dumping operation. Moreover, the volume of the bucket does not have a pronounced interaction effect. In the dumping operation, the work amount of bulldozer decreases as dumping pile increases. The design of the dumping operation must consider the total efficiency of ground leveling operation and forming dumping the area.
基金Financial support from the National High-Tech Research and Development Program of China(No.2012AA062004)the National Natural Science Foundation of China(No.51034005)
文摘According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport passage is analyzed in aspects such as the internal dump occupation,dragline operation efficiency,coal transport distance,upper stripping distance and shifting quantities.The middle passage should be given priority in thick overburden open pit mine because the dragline system is only responsible for part stripping task.According to characteristics of middle passage,the transport passage is divided into parallel climbing,vertical climbing and horizontal transport.In addition,the transport passage structure optimization model and shifting distance optimization model are established in this paper.The case study in Heidaigou open pit mine shows that,the parallel climbing height is accounted for about 60%of the total height,and reasonable shifting distances of the first mining area and the second mining area are 240 and 320 m.Sensitivity analysis shows that,the total passage height has important influence on the shifting step,so it is with the stripping height and passage construction cost to the passage structure.
