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A gold — copper mine in Xinjiang is located at a high altitude. The industrial site is limited, with complex terrain and a sensitive environment. The distance between the dressing plant and the tailings pond is long and the height difference is significant. Under the conditions of simultaneous mining of upper and lower mining areas and coexistence of self-flow and pumping, to fully balance underground filling and tailings conveying and achieve green mining of mines, the paper, based on the development system, established the optimal thickening method for mine tailings filling and proposed 3 feasible solutions for the coordination of tailings conveying and filling system layout, which are compared and analyzed from multiple aspects including process flow, engineering investment, operating costs, and surface environment protection. The results show that the mine is most suitable for the deep cone thickening scheme, and the filling station is arranged at the surface of 2800 m air return audit + two-stage tailings conveying( Scheme I ), which is obviously better than Scheme II and III in terms of investment, operating costs, present value cost, and reliability. Besides, the system has high reliability and is easy to manage. The research provides solutions for the construction of tailings conveying and filling systems of the same type of mine. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to prevent the occurrence of rockburst accident caused by the stress concentration of the middle rock pillar in the near-vertical coal seam and affect the mining of the lower coal seam in the known goaf, taking Wudong coal mine in Xinjiang as an example, based on the special geological and mining conditions of the mine, through the simulation experiment and numerical analysis of similar materials, the variation law of the stress distribution of the middle rock pillar with the increase in mining depth is analyzed. A presplitting blasting pressure relief technology of drilling a construction chamber in the middle of the rock column is proposed to form a buffer layer in the rock wall and effectively prevent the continuous downward movement of stress. In order to achieve the optimal blasting effect, the finite element numerical simulation software GTS NX is used to carry out the chamber rock mass hole blasting simulation experiment, the three influencing factors of blasting effect, such as charge quantity, blast hole diameter, and blast hole row spacing, are comprehensively considered, and the optimal pressure relief blasting parameters with the radius of borehole blasting crack circle and the width of plastic zone as the index are determined. The experimental results show that under the condition of determining the physical and mechanical parameters of coal and rock, the blast hole diameter has become the main control factor affecting the blasting pressure relief effect, followed by the charge amount. Through 9 groups of orthogonal tests, the optimal combination of the three indexes is 6 kg charge, 150 mm hole diameter and 10 m hole row spacing. The practical engineering application results of the combination are tested by downhole transient electromagnetic detection (TEM), and it is found that the pressure relief effect is obvious. The preliminary conclusions of the study have guiding significance for the pressure relief and erosion prevention of the middle rock pillar in Wudong mine and provide experimental methods and theoretical basis for the determination of blasting pressure relief parameters in other mines. [ABSTRACT FROM AUTHOR]

Reasonable mining procedures are very important for energy saving in open-pit mines. However, studies on mining procedures in the first mining area of large open-pit mines characterized by thick and inclined coal seams are limited. The Hongshaquan open-pit mine located in Xinjiang, China was used as an example in this study to relieve space strain of soil drainage and reduce stripping weighted transport distance of the mining scheme in the first mining area of large open-pit mines characterized by thick and inclined coal seams. Three mining schemes, including eastward fan-shaped, southward partial gentle, and southward overall gentle turning schemes, were put forward. Stripping ratio, coal mining, stripping distance, and lifting height of the three schemes were compared and analyzed while considering technical and economic indicators. Accordingly, the stability of typical slopes in the stope and inner and outer dumps of the open-pit mine under the optimal mining scheme was analyzed using numerical simulation. Results demonstrate that stripping ratios of the three schemes are stable below 4 cubic metres per ton. The eastward fan-shaped turning scheme presents the minimum stripping distance, stripping lifting height, and mining distance, while the southward overall gentle turning scheme shows the minimum lifting height. The eastward fan-shaped turning scheme demonstrates enhanced short-term economic benefits, while the southward overall gentle turning scheme exhibits improved long-term economic benefits. The southward overall gentle turning scheme combined with the future expansion demand of the Hongshaquan open-pit mine, difficulty in the mining process, upgrading of mining technology, and other factors was adopted to mine the first mining area. Slope stability coefficients of the stope and inner and outer dumps meet the safety reserve coefficient and safety production requirements under this scheme. This study can provide a reference for the comparison and selection of mining procedures and slope stability analysis of similar open-pit coal mines. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• The CSAMT method is used to image acidic contaminants of uranium mine in Yili Basin. • The resistivity model identified the scale and position of the contaminant plumes. • The surrounding low permeability sandstones confine the contaminant plumes. • The porosity of uranium-bearing sandstones changes due to acidification and plugging. Acid in-situ uranium leach mining is an effective, popular technology for extracting uranium without large uranium mill tailings. However, acid in-situ leaching causes extremely high concentrations of acidic contaminants in aquifers. To represent the migration and range of acidic contaminant pollutants in confined aquifers, this study applied the controlled source audio-frequency magnetotellurics (CSAMT) method to a uranium mining area located in the Yili Basin, Xinjiang, northwest China. We collected ten CSAMT profiles from 364 sites with an average site interval of 20 m. The electrical resistivity model of the uranium mining area was obtained via two-dimensional inversion using CSAMT data, with 23 frequencies, ranging from 8192 Hz to 4 Hz. Combined with geological, geochemical, and well log data, this resistivity model was successfully used to identify the scale and position of acid contaminant plumes beneath the uranium mining area, which appear as electrically well-defined features that closely coincide with the distribution of sulfate and uranium ions in groundwater. With uranium mining activities ceasing, the scale of acid contaminant plumes has been reduced, owing to the natural attenuation of the aquifer or the contaminants well confined in the mining site. The low-permeability sandstone surrounding the aquifer was imaged as a resistive feature, which confines the contaminant plumes to the uranium mining area and slows the downstream migration of contaminants. According to the modified Archie's law, the porosity of the sandstone bearing uranium beneath the injection well zone increases, owing to acidification, while the porosity of the sandstone beneath the production well zone decreases, owing to pore plugging. [ABSTRACT FROM AUTHOR]