热复合化学方法改善极强敏感性稠油油藏开发效果机理  

A study on a thermal compound chemical method for improving development efficiency of heavy-oil reservoirs with strong sensitivity

作　　者：曹嫣镔[1,2] 于田田[2] 林吉生[2] 刘冬青[2] 何绍群[2] 王全 夏道宏 

机构地区：[1]中国石油大学化学工程学院,山东青岛266580 [2]中国石化胜利油田公司采油工艺研究院,山东东营257000

出　　处：《石油学报》2013年第1期128-132,共5页Acta Petrolei Sinica

基　　金：国家重大科技专项(2011ZX05011-002)资助

摘　　要：胜利油田极强水敏性稠油油藏主要分布在金家油田,储量在2 000×104 t以上,该类油藏水敏指数在0.9以上,单纯注蒸汽热采开发效果差,无法实现有效动用。笔者针对以上矛盾,开展了热复合化学方法开采技术研究。利用金家油田真实岩心开展了不同驱替方式条件下热复合化学方法岩心驱油效率评价实验,利用X衍射、扫描电镜、铸体薄片、压汞实验研究了蒸汽+高温防膨剂、蒸汽+高效驱油剂、蒸汽+高效驱油剂+高温缩膨剂不同驱替方式下岩心黏土矿物组分变化、黏土在孔喉分布状态、孔喉半径分布规律、驱替效率。研究结果表明,蒸汽+高温驱油剂+高温缩膨剂的热复合化学驱替方式可促进蒙脱石向伊利石的转变,同时溶蚀部分高岭石,大幅度提高油藏孔喉渗流通道,形成大的"热蚯孔",大幅度提高敏感性稠油油藏的渗透率和驱替效率。Heavy-oil reservoirs with extremely strong water sensitivity in the Shengli oilfield are mainly distributed in the Jinjia oilfield and their reserves amount to more than 20 million tons. In addition, the thermal recovery effect only by steam injection seems poor and it is difficult to effectively produce these reserves because the water sensitivity index for this kind of reservoirs exceeds 0.9. In view of the above contradiction, a thermal compound chemical method research was carried out, in which real cores from the Jinjia oilfield were used to evaluate different displacement manners based on thermal compound chemical flooding, such as the vapor ＋ high temperature antiswelling agent, steam＋ high-performance oil displacement agent, and steam＋ high-performance oil displacement a- gent ＋ high-temperature condensation agent. Composition changes of clay minerals, clay distributions in pore throats and radius distri butions of pore throats were measured by means of X diffraction, scanning electron microscope, cast thin section and mercury-injection in order to explore principle mechanisms of the enhanced oil recovery with the thermal compound chemical method under high-tempera ture conditions. The results showed that the thermal compound chemical displacement manner with the steam ＋ high-temperature oil dis- placement agent ＋ high-temperature condensation agent can promote the transformation of montmorillonite to illite and the dissolution of part kaolinite at the same time, which can greatly improve pore-throat flow channels of reservoirs to form large ＂hot-wormholes＂ that remarkably increase the permeability and flooding displacement efficiency of heavy-oil reservoirs with strong water sensitivity.

关 键 词：强水敏 稠油油藏 热采 热复合化学驱 电镜分析 

分 类 号：TE345[石油与天然气工程—油气田开发工程]