煤储层等温吸附实验过程中参数敏感性分析  

Analysis on parameter sensibility during isothermal adsorption experiment of coal reservoir

作　　者：马行陟[1,2] 宋岩[1,3] 柳少波[1,2] 田华[1,2] 郑永平[1,2] 郝加庆[1,2] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油天然气集团公司盆地构造与油气成藏重点实验室,北京100083 [3]中国石油大学,北京102249

出　　处：《煤田地质与勘探》2014年第6期34-39,共6页Coal Geology & Exploration

基　　金：国家重点基础研究发展计划(973计划)项目(2009CB219600);国家科技重大专项项目(2011ZX05003);中国石油天然气股份公司"十二五"科技攻关项目(2011A-0203)

摘　　要：容量法等温吸附实验是测定煤储层吸附性和含气性的常用手段。实验装置中的参考缸体积V1、装有样品时的自由空间体积V2和压力表对等温吸附实验有着直接的影响,但是这三者对实验影响的程度目前还没有系统的认识。为了理清实验过程中各参数的影响和提高等温吸附实验的测试精度,基于波义尔定律建立了煤储层容量法等温吸附实验稳定性和精确性分析的数学模型,利用Matlab软件对吸附实验过程进行了数值模拟。研究表明,吸附实验的稳定性和准确性受压力表、参考缸的体积V1和样品缸装有样品时的自由空间体积V2的控制,压力表测量精度越高,等温吸附实验的稳定性和精确性就越好;压力表精度一定时,V1和V2的体积较小且匹配组合满足一定的条件,吸附实验才能达到较好的稳定性和精确性。利用优化方法得到的结果对鄂尔多斯盆地东缘韩城地区中煤阶煤储层开展等温吸附对比实验,结果表明,经过优化组合的吸附实验测试结果稳定和精度都有所提高,吸附量的最大差值为1.45 cm3/g,远低于未经过优化的实验所测吸附量的差值5.27 cm3/g。Volumetric adsorption experiment is the primary method to determine the adsorption capability andgas content of coal reservoirs. Reference cylinder volume V1, free volume V2 in sample cylinder and pressuregauge precision were identified as the key factors influencing adsorption experiment. To understand how theparameters impact isotherm adsorption experiment results and improve the precision of the experiment, in thispaper, stability analysis and accuracy analysis were performed for adsorption experiment according to Boyle＇slaw. Based on the established models, the adsorption experiments are simulated by Matlab software. The resultshows that the stability and the accuracy of experiment are controlled by V1, V2, pressure gauge precision andreference cylinder volume. The higher pressure gauge precision, the more stable and precise adsorptionexperiment is. When the pressure gauge precision is fixed, only V1 and V2 are smaller and satisfy certainconditions which have been simulated can the experiment achieve good stability and precision. Comparativeisothermal adsorption experiment was conducted on medium rank coal from Hancheng area in the eastern Ordosbasin by using the results obtained from optimization. Result indicates that the quality of adsorption results isimproved, the maximum adsorption difference is 1.45 cm^3/g, far less than 5.27 cm^3/g from the experiment notoptimized by models.

关 键 词：吸附 煤储层 波义尔定律 容量法 敏感性分析 

分 类 号：P618.13[天文地球—矿床学]