CO2混相驱技术在特低渗透滩坝砂油藏的开发实践及效果评价  

Application and evaluation of CO2 miscible flooding in extra-low permeability beach-bar sand reservoirs

作　　者：刘小波 LIU Xiaobo(Dongsheng Petroleum Development Group Company Limited of Shengli Oilfield,Dongying City,Shandong Province,257200,China)

机构地区：[1]胜利油田东胜精攻石油开发集团股份有限公司,山东东营257200

出　　处：《油气地质与采收率》2020年第3期113-119,共7页Petroleum Geology and Recovery Efficiency

摘　　要：正理庄油田樊142块为典型的低孔、特低渗透滩坝砂油藏,弹性开发递减快,采收率低。为研究特低渗透滩坝砂油藏CO2混相驱的可行性,优选正理庄油田樊142块的樊142-7-斜4井组开展CO2混相驱先导试验。室内研究结果表明,CO2具有较好的降黏和膨胀地层原油的作用,能够大幅度提高采收率。利用数值模拟,进行CO2驱恢复地层能量优化设计,井组采用反七点法井网、周期注采、合理地层压力保持在1.3MMP,可获得较好的采收率和经济效益。现场试验效果证实,CO2具有较好的注入能力,井组地层压力显著恢复,井组混相阶段注气换油率为0.44 t/t,采收率提高6.2%,取得较好的增产效果,可见CO2混相驱是提高特低渗透油藏采收率的有效手段。Block Fan142 in Zhenglizhuang Oilfield is a typical low porosity,extra-low permeability beach-bar sand reservoir with the rapid production decline and low recovery during the elastic development period.In order to study the feasibility of CO2 miscible flooding in the extra-low permeability beach-bar sand reservoirs,a pilot test was carried out in Well Group F142-7-X4 of the Block Fan142.The results show that CO2 has a good effect on reducing viscosity and swelling formation oil,which can dramatically improve oil recovery.By using numerical simulation,the formation pressure may be restored through the optimization design of CO2 flooding.The higher recovery and economic benefit of the well group may be obtained at the conditions of the inverted seven-point pattern,the cyclic injection and production,and maintaining formation pressure at 1.3MMP.The field test results show that CO2 has a good injection capacity and the formation pressure of the well group is significantly restored.A good stimulation performance is achieved.The oil exchange rate by gas injection of the well group at the miscible phase is 0.44 t/t and oil recovery factor of well group is increased by 6.2%.The CO2 miscible flooding is an effective means to improve the recovery of the extra-low permeability reservoirs.

关 键 词：特低渗透油藏 CO2 混相驱 现场试验 提高采收率 

分 类 号：TE357.45[石油与天然气工程—油气田开发工程]