Price Estimation of Coal Seam and Its Application in the Optimization of the Mining Sequence: A Case Study.

Coal price may vary significantly within a given coal seam, and the accurate characterization of coal price plays an important role in the rational development and utilization of coal resources. A geostatistics-block-based method is proposed to obtain the spatial correlation of borehole survey data and map the heterogenous distribution of coal seam thickness and coal quality (including calorific value, volatile content, ash content, and sulfur content). A block model of thermal coal price is next established considering the spatial distribution of coal quality parameters. Taking an undisclosed coal mine as an example, the estimation process of coal price block model is described in detail, and the mining sequence among several panels is optimized considering the heterogenous coal price. The coal price ranges from 814 to 1671 Chinese Yuan/t within the research area, and the net present value is increased by 1.53% after the optimization of the mining sequence. The result indicated that the coal price is generally heterogenous in a coal seam, and it has a significant influence on the mining sequence. The accurate modeling of coal seam properties has wide applications in mining engineering.