大佛寺煤储层甲烷解吸的传质过程研究

以CH4解吸过程CH4的质点运移过程、能量来源与传递为研究目标，剥离大佛寺4号煤的镜煤与暗煤，进行工业分析、煤岩分析、液氮吸附、压汞实验、润湿性测定、吸附/解吸等对比实验，进行吸附热计算。研究认为:按照传质功能分类，煤的孔隙分半开放孔与连通孔,镜煤吸附量大，以半开放孔为主，暗煤以连通孔为主;降压湍动引起水的蒸汽化，H2O的吸附放热导致CH4的解吸，降压解吸的本质是竞争吸附，表现为置换解吸;煤层气的产出的传质过程是低溶解度的CH4气核空化过程(Cavitition)。煤的吸水、平衡水实验与CT扫描结果初步验证了我们对煤层气产出的传质过程认识。研究结果补充了解吸作用的能量来源问题。

Mass transfer process of desorption of CBM in Dafosi coal reservoir

Targeted at the particle migration process,energy source and transmission of CH4 during its desorption process,the vitrain and durain in No.4 Mine of Dafosi are stripped to conduct a series of contrast experiments concerning industrial analysis,coal petrographical analysis,liquid nitrogen adsorption,mercury injection experiments,wetting testing,adsorption and desorption,and then the adsorption heats are calculated.It is discovered that (1) In terms of mass transfer function,coal pores are classified into semi-open pores and interconnected pores.With large adsorbing capacity,vitrain mainly has semi-open pores,and durain mainly has interconnected ones.(2) Depressurization turbulence leads to water vaporization.Heat release from the adsorption of H2O leads to the desorption of CH4.The nature of depressurization desorption is competitive adsorption,manifesting as replacement desorption.(3) The mass transfer process of CBM is a cavitation process of CH4 gas nucleus with low solubility.The water adsorption of coal,equilibrium water experiments and the results of CT scanning all basically verify the understanding of the mass transfer process of CBM production.The research results supplement the issue of energy source of adsorption.