Study on the Connectivity of Pore Structure of Coal in Three-Dimensional Space

The connectivity of pore is main factor which affect the permeability of coal seam. In this paper, we perform an experiment on the pore structure in blind coal sample and lean coal sample, a non-destructive inspection equipment “micro CT experimental system” is used to scan coal samples, the least scanning unit resolution of the system is 0.5 μm. Based on the micro-CT images, the 3D digital sample of coal is reconstructed by using the software developed by author, by images segmentation, binarization, reappeared the distribution of pore cluster in three-dimension space, and analyzed the connectivity of pore cluster in coal sample. The experimental result indicated: the major factor influencing on gas drainage efficiency is amount of pores included in the largest pore cluster.