高温高压致密气藏岩石扩散系数测定及影响因素  

Rock diffusion coefficient measuring and its effecting factors of tight gas reservoir under high temperature and high pressure

作　　者：王晓波[1,2,3] 陈践发[1] 李剑[2,3] 王东良[2,3] 李志生[2,3] 柳广弟[1] 谢增业[2,3] 孙明亮[1] 

机构地区：[1]中国石油大学油气资源与探测国家重点实验室北京102249 [2]中国石油天然气股份有限公司勘探开发研究院廊坊分院,河北廊坊065007 [3]中国石油天然气集团公司天然气成藏与开发重点实验室,河北廊坊065007

出　　处：《中国石油大学学报（自然科学版）》2014年第3期25-31,共7页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家重大科技专项(2011ZX05007);国家“973”项目(2007CB209503);国家自然科学基金项目(41102086)

摘　　要：根据气体在浓度梯度下通过岩样自由扩散的原理,利用建立的高温高压致密气藏岩石扩散系数测定方法,对四川盆地须家河组、鄂尔多斯盆地上古生界致密气藏岩石样品开展试验分析,并探讨物性、温度、注气平衡压力、围压、饱和介质等因素对致密气藏岩石扩散系数的影响.研究表明：物性是致密气藏岩石扩散能力的基础,对其具有重要控制作用,二者呈正幂函数相关关系;温度对致密气藏岩石扩散系数具有促进作用,二者呈指数相关关系;孔隙流体压力、上覆地层压力对致密气藏岩石扩散能力均具有抑制作用,呈负幂函数相关关系,且上覆地层压力的影响与岩性密切相关（泥岩大于砂岩）;饱和介质条件致密气藏岩石干样、湿样扩散系数总体相差2～3个数量级.Based on the assumption that gas free diffusion is controlled by concentration gradient in rock samples,the typical tight gas resevoir rock samples from Xujiahe Formation in Sichuan Basin and upper Paleozoic in Ordos Basin were studied by establishing a method measuring the tight gas reservoir rock diffusion coefficients under high temperature and high pressure.Then,the influences of physical properties,temperature,gas injecting pressure,surrounding pressure and saturated media conditions on diffusion coefficient of tight gas reservoir rock samples were intensively discussed.The results show that rock physical properties are the governing factor and have the dominant controlling effects on rock diffusive abilities,and have a positive power function relationship with tight gas reservoir rock diffusion coefficients.Temperature has large positive promoting effects on rock diffusive abilities,and a positive exponential relationship with rock diffusion coefficients.Both porous flu-id pressure and overlying rock pressure have suppressing effects and have negative power function relationships with tight gas reservoir rock diffusion coefficients,especially overlying rock pressure which has great relationship with lithology,e.g.mudstone is larger than sandstone.The difference of rock diffusion coefficients between saturated media and dry samples is generally about 2-3 orders of magnitude.

关 键 词：高温高压 致密气藏 扩散系数 影响因素 孔隙流体压力 上覆地层压力 饱和介质条件 

分 类 号：TE122[石油与天然气工程—油气勘探]