The physical and chemical texture of tectonically deformed coals produced by various formational mechanisms are different from those of primary coals,thus resulting in major differences among the physical properties o...The physical and chemical texture of tectonically deformed coals produced by various formational mechanisms are different from those of primary coals,thus resulting in major differences among the physical properties of the reservoirs of these coals. We have studied the adsorption/desorption be-havior of tectonically deformed coals by the use of isothermal adsorption/desorption experiments un-der equilibrium moisture condition. Experiments of isothermal adsorption/desorption of methane or multi-component gases have indicated that,the adsorption curves of coals with a low degree of tec-tonic deformation conform to the type of isothermal adsorption curve described by the Langmuir equation; the methane adsorption curves of coals with strong tectonic deformation cannot be de-scribed by the Langmuir equation. The adsorption/desorption process of methane and multi-compo-nent gases in the deformed coals is not consistent with primary coals,which form an effect of hys-teresis in different kinds of tectonically deformed coals. With the change of pore structure of tectoni-cally deformed coals at reservoir condition,the added adsorbed CH4 in the experiments is desorbed on the pore surface of coals during the pressure reduction process. Thus,the result shows that the ad-sorption volume in the process of desorbing is greater than that in adsorbing. Because of the defor-mation,structural change,and transformation of the adsorption potential field of coals,it is essential to form a new kind of isothermal adsorption curve and the hysteresis effect of the desorption process.展开更多
CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of g...CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of greenhouse gases and the emerging commercial significance of CBM. Reservoir-simulation technology,as a useful tool of reservoir development, has the capability to provide us with an economic means to solve complex reservoir-engineering problems with efficiency. The pore structure of coal is highly heterogeneous, and the heterogeneity of the pores depends on the coal type and rank.展开更多
基金Supported by National Basic Research Program of China (Grant Nos.2006CB202201 and 2009CB219601)National Natural Science Foundation of China (Grant Nos.40772135,40642013 and 40172058)
文摘The physical and chemical texture of tectonically deformed coals produced by various formational mechanisms are different from those of primary coals,thus resulting in major differences among the physical properties of the reservoirs of these coals. We have studied the adsorption/desorption be-havior of tectonically deformed coals by the use of isothermal adsorption/desorption experiments un-der equilibrium moisture condition. Experiments of isothermal adsorption/desorption of methane or multi-component gases have indicated that,the adsorption curves of coals with a low degree of tec-tonic deformation conform to the type of isothermal adsorption curve described by the Langmuir equation; the methane adsorption curves of coals with strong tectonic deformation cannot be de-scribed by the Langmuir equation. The adsorption/desorption process of methane and multi-compo-nent gases in the deformed coals is not consistent with primary coals,which form an effect of hys-teresis in different kinds of tectonically deformed coals. With the change of pore structure of tectoni-cally deformed coals at reservoir condition,the added adsorbed CH4 in the experiments is desorbed on the pore surface of coals during the pressure reduction process. Thus,the result shows that the ad-sorption volume in the process of desorbing is greater than that in adsorbing. Because of the defor-mation,structural change,and transformation of the adsorption potential field of coals,it is essential to form a new kind of isothermal adsorption curve and the hysteresis effect of the desorption process.
文摘CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of greenhouse gases and the emerging commercial significance of CBM. Reservoir-simulation technology,as a useful tool of reservoir development, has the capability to provide us with an economic means to solve complex reservoir-engineering problems with efficiency. The pore structure of coal is highly heterogeneous, and the heterogeneity of the pores depends on the coal type and rank.
