低渗砂岩油藏CO_(2)驱相态及组分变化规律  

Phase State and Component Change Law of CO_(2) Flooding in Low-Permeability Sandstone Reservoirs

作　　者：刘建仪 杨雪[1,2] 刘勇 Liu Jianyi;Yang Xue;Liu Yong(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu,Sichuan 610500,China;Southwest Petroleum University,Chengdu,Sichuan 610500,China;PetroChina Liaohe Oilfield Company,Panjin,Liaoning 124010,China)

机构地区：[1]油气藏地质及开发工程国家重点实验室,四川成都610500 [2]西南石油大学,四川成都610500 [3]中国石油辽河油田分公司,辽宁盘锦124010

出　　处：《特种油气藏》2022年第6期91-96,共6页Special Oil & Gas Reservoirs

基　　金：国家科技重大专项“缝洞型油藏注气配套工艺技术优化研究”(2016ZX05053-011)。

摘　　要：为了解低渗砂岩油藏W区块注气开发过程中的相态、油气组分变化和储层原油对注气的反应,利用质量守恒和状态方程等经典理论,以CO_(2)气体为注入介质,通过注气膨胀、气相色谱实验和PVT相平衡模拟软件进行原油组分变化特征研究。结果表明:CO_(2)注入量增至0.814 mol时,泡点压力升高了0.96倍,样品体积膨胀了2.09倍,流体中CO_(2)含量由背景值的0.6%逐渐升至81.0%,说明该区泡点压力主要受轻烃组分控制,原油组分因气体的溶解和分离发生明显改变。该研究可为东濮凹陷低渗砂岩油藏注气提高采收率、油气输运工艺设计、开发方案编制提供技术支持,对其开发具有重要的实际意义。To work out the phase state,changes in oil and gas components and the response of crude oil to gas injection in the gas injection development of Block W in low-permeability sandstone reservoirs,classical theories such as mass conservation and equation of state were employed to study the characteristics of crude oil component changes by gas injection expansion,gas chromatography test and PVT phase equilibrium simulation software,with CO_(2)gas as injection medium.The result shows:When the CO_(2)injection amount increased to 0.814 mol,the bubble point pressure increased by 0.96 times,the sample volume expanded by 2.09 times,and the CO_(2)content in the fluid gradually increased from 0.6% of the background value to 81.0%,indicating that the bubble point pressure was mainly under the control from the light hydrocarbon components,and the crude oil components changed significantly due to the dissolution and separation of gas.This study technically supports the oil recovery enhancement by gas injection,the design of oil and gas transmission technology,and the preparation of development plan of low-permeability sandstone reservoirs in Dongpu Sag,as well as having important practical significance for its development.

关 键 词：相态 组分 泡点压力 状态方程 CO_(2) 低渗砂岩油藏 

分 类 号：TE345[石油与天然气工程—油气田开发工程]