A Study of Directional Permeability and Gas Injection to Flush Coal Seam Gas Testing Apparatus and Method

摘要

Due to the reservoir rocks are often anisotropic in permeability, and traditional permeability testing apparatus cannot well carry out the directional permeability testing. The specialised permeability apparatus known as multi-functional outburst research rig (MFORR) is used to study the directional permeability under various confining pressures, and the relevant testing method and results are introduced as well. The MFORR testing results with of an Australian coal specimen from Sydney Basin show that this new directional permeability testing apparatus and method can give the promising results in radial permeability test. Compared to the traditional triaxial testing methodology, it can well study the directional permeability properties of anisotropic rocks and complement the traditional triaxial testing method. Moreover, the better accordance with actual conditions of coalbed methane extraction and other field engineering is another advantage of this new method. Besides, a promising result in the gas injection to flush Coal Seam Gas (CSG) testing using MFORR indicates that it is a direct way to analyse the gas displacement process by injecting through the drilling hole to the or saturated coal.