Experimental Study Of Effect On Gas Permeation Migration About Tectonic Coal With Structure Differences

The coal whose coal body structure greatly damaged is an obstacle for coalbed methane production and a difficulty for coal and gas outburst prevention. So, the study about tectonic coal with different particle structures has significant meaning for coal bed methane production and coal and gas outburst prevention. Based on different size coal particle, making each tectonic coal body with different particle size of coal sample, the gas migration and coal body outburst are studied in this paper. The main contents in this paper, as follows:1. Getting the coal sample from east of Zhuji coal mine. Because the goal of the paper, the coal sample is smashed to getting coal particle with different granule size. Analyzing the grading characteristics of each coal particle.2. The experiment about gas migration characteristics in coal with different structure is done. In this chapter, the gas injection-adsorption-desorption-migrati on is operated to each coal sample with different particle structure. The flow da tas are processed by the matlab function fitting toolbox and getting the result th ere are linear or binomial migration characteristics about coal body with differe nt particle structure.3. The experiment about gas migration characteristics in coal body with ins tantaneous pressure relief is done. The mathematical model of effective stress、p ore permeability about coal with particle structure is established. At the same ti me, the dynamic characteristics of effectiveness stress、pore permeability about i nstantaneous unloading coal are also studied by experiment. Based on these, the gas migration characteristics about instantaneous unloading coal are studied. Th e result show all the effective stress between coal granule、the permeability、p orosity has the index change relation. The gas migration has the potential trend from linear to binomial when the external stress on the loaded coal is relieved4. The experiment of the coal and gas burst about coal with different particle structure is done. Before and after coal and gas burst, contrasting the coal body structure、gas pressure change、gas velocity and coal body permeability about coal body with different particle structure. Fitting the dates got at the moment coal and gas burst and studying the gas migration characteristics as well.