Observation and research on surface crack structure of coal based on electronic scanning technology

Abstract

Based on the background of the 2 # coal seam mainly mined by Caojiatan Coal Mine in Yulin Mining Area in northern Shaanxi, this paper adopts the Scanning electron microscope test method to obtain the fracture size and structural characteristics of coal samples through the process of sample preparation drying testing analysis. After testing, the cracks in the main coal seam samples of Yulin mining area in northern Shaanxi show irregular distribution, with small branch cracks mainly derived from larger main cracks. The closed form crack structure is a wedge-shaped structure, while the open form crack width is in an disordered state. Some cracks have no fixed width or size, and the main crack width range is 90μm~617μm, the width range of branch fine cracks is 0-21 μm; It can provide basic support for the application of water injection dust reduction engineering in the later stage.