Optimisation of Working Line Length during the Period of Gently Inclined Slope in Tilted Coal Seam Open-Pit Mine

Abstract

In the initial production phase of an inclined seam opencast mine, due to initial investment and production capacity constraints, zoning or phasing is usually used, resulting in changes in the length of the working line during the transition of the mining area. To simplify the process, this article analyses the changes in the length of the working line during the period of slow gang steering in inclined seam opencast mines. In order to simplify the process, this article analyses the changes in the length of the working line in each period. The relationship between the length of the working line and the realm stripping ratio in the overlapping area of the two mining areas is discussed, and the variation in the realm stripping ratio and the economically reasonable stripping ratio under different working line lengths is illustrated. The advantages and disadvantages of the different optimization options are described. The optimization method was applied to the Zhundong opencast coal mine to calculate the working line lengths for the two stages. The optimized stripping ratio for the second-stage south gang location is equal to the economically reasonable stripping ratio of 3.50 m3/t, which reduces coal compression and improves economic efficiency, and is a guideline for the study of the working line lengths in each stage of the open-pit mine slow gang turning.