The Analysis Of Tectonically Deformed Coal Pore Structure And Adsorption In Hancheng Area

Take the tectonically deformed coal sample in Hancheng area Shanxi province as the research object,using the original summed up data and macro macroscopic observation,described tectonically deformed coal sample petrology characteristics.Using SEM,MIP and low temperature nitrogen adsorption experiment,analyzed pore structure characteristics of tectonically deformed coal sample.Using isothermal adsorption experiment,analyzed coal sample adsorption performance difference in Hancheng area.This paper deeply analyzes the tectonically deformed coal sample's pore structure and adsorption in Hancheng area,have a great influence on coalbed gas occurrence and reservoir.Using the original summed up data and macro macroscopic observation,the coal sample of Hancheng area can be divided into fragmented coal,granulated coal and mylonitized coal.Fragment coal remain the native structure and bedding,usually see block and layered structure,they have slip plane and its surface develop exogenetic fractures,using hand can break into small pieces.Granulated coals have discontinuous bedding and granular structure,using hand can break about 1mm.Mylinitized coal have no native structure,but they develop micro fold,its hardness is low,using hand can break them into powder.Fragmented coal have more endogenous fractures,granulated coal have moreexogenetic fractures,mylonitized coal have more shear fractures.Using SEM,MIP and low temperature nitrogen adsorption experiment to study coal pore structure characteristics.Using SEM can see different categories of pore.we know fragment coal have more macropore,granulated and mylonitized coal have more small pore.Using MIP and low temperature nitrogen adsorption experiment,we can find relation between pore volume,surface area and structure,metamorphic.Tectonic stress is grow,pore volume and surface area is grow.The proportion of sub-Micropore,micropore and mesopore is increase,structure power have more influence in “big” pore.The Ro,max is grow,pore volume and surface area is grow,except mesopore and macropore.The pore volume and surface area of lean coal is greater than coking coal.Metamorphic have more influence in “small” pore.Using isothermal adsorption experiment to study the relation between adsorption and structure power,metamorphic.Adsorption and structure power have positive relation.The Ro,max is grow,the adsorption is increase.The adsorption of lean coal is greater than coking coal.The adsorption have positive relation with “samll” pore,neither “big” pore.