页岩气藏地质储量优化计算方法  

An optimal calculation method for the geological reserves of shale gas reservoirs

作　　者：何浪 梅海燕 胡欣芮 张茂林[2] 毛恒博 HE Lang;MEI Haiyan;HU Xinrui;ZHANG Maolin;MAO Hengbo(School of Petroleum Engineering,Southwest Petroleum University,Chengdu 610500,Sichuan,China;Hubei Cooperative Innovation Center of Unconventional Oil and Gas,Yangtze University,Wuhan 430100,Hubei,China;No.12 Oil Production Plant,PetroChina Changqing Oilfield Company,Heshui 745400,Gansu,China)

机构地区：[1]西南石油大学石油与天然气工程学院,610500 [2]长江大学非常规油气湖北省协同创新中心 [3]中国石油长庆油田公司采油十二厂

出　　处：《石油钻采工艺》2019年第2期197-202,共6页Oil Drilling & Production Technology

基　　金：国家科技重大专项“潜江与泌阳凹陷页岩油勘探开发目标评价”(编号:2016ZX05049005010);国家科技重大专项“涪陵地区五峰组-龙马溪组页岩气压裂及采气规律研究”(编号:2016ZX05060026)

摘　　要：精确评价地质储量是页岩气藏开发规划的重要一步,虽然理论方法不断完善,但仍存在不足。在页岩气藏中,吸附气不仅包含甲烷,还存在一定比例的乙烷等其他烃类气体,应采用多组分吸附模型计算吸附气储量。同时,天然裂缝中大量存在的天然气也不能忽略。此外,干酪根中也溶解了一定的气体,忽略会导致较大误差。采用多组分吸附模型,考虑了吸附相占据的孔隙度、裂缝游离气及干酪根中的溶解气,建立了一种优化的页岩气藏地质储量计算模型。实例分析发现,裂缝游离气和溶解气占总储量的比例分别为10.41%和7.05%,传统方法计算得到的吸附气储量偏小,基质游离气储量偏大,总储量偏小。为了合理评价页岩气藏地质储量,应采用多组分吸附模型,考虑吸附相孔隙度且不能忽略裂缝游离气及干酪根中的溶解气。Evaluating the gas in place accurately is one important part of the development planning of shale gas reservoirs, and its theories and methods are being improved continuously, but there are still some deficiencies. The adsorbed gas in shale gas reservoirs not only contains methane, but also a certain percentage of ethane and other hydrocarbon gases, so the adsorbed gas reserves shall be calculated by using the multi-component adsorption model. In addition, there is natural gas in a great number of natural fractures, which is not negligible. What’s more, some gas is dissolved in the kerogen, and greater deviation will be induced if the dissolved gas is neglected. The multi-component adsorption model is used, the porosity occupied by the adsorbed phase, the free gas in fractures and the dissolved gas in kerogen are taken into account, and a modified calculation method for the gas in place of shale gas reservoirs is established. Case analysis indicates that the percentages of fracture free gas and dissolved gas in the total reserves are 10.41% and 7.05%, respectively. The adsorbed gas reserves calculated by using the traditional method is lower, the matrix free gas reserves is higher and the total reserves is lower. In order to evaluate the gas in place of shale gas reservoirs rationally, it is necessary to adopt the multi-component adsorption model, and take into consideration the porosity of the adsorbed phase, as well as the free gas in fractures and the dissolved gas in kerogen.

关 键 词：地质储量 页岩气藏 多组分吸附 裂缝游离气 溶解气 吸附相孔隙度 

分 类 号：TE155[石油与天然气工程—油气勘探]