特低渗油藏CO_2非混相驱封窜实验研究  

Experimental research of CO_2 channeling law in the immiscible CO_2 flooding of the ultra-low permeability reservoirs

作　　者：张磊[1,2] 赵凤兰[1] 侯吉瑞[1] 端详刚[1] 王嘉晨 徐宏明 

机构地区：[1]中国石油大学(北京)提高采收率研究院,北京昌平102249 [2]中国石油大学(北京)石油工程学院,北京昌平102249

出　　处：《西安石油大学学报（自然科学版）》2013年第5期62-65,3,共4页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家自然科学基金"CO2在多孔介质中扩散规律的影响因素及机理研究"(编号:50804052)

摘　　要：为了提高特低渗油藏CO2驱的开发效果,以靖边三叠系延长组长6段为研究对象,设计了5组不同的驱油实验(生产压差分别为1 MPa、2 MPa、3 MPa、4 MPa、5 MPa)分析CO2驱过程中的窜逸规律.实验结果表明,随着压差增加,见气时间和气窜时间缩短,但是最终采收率却呈现出先增加后降低的趋势,且见气前后产量大幅增加,是开采的最主要时期.实验显示在3 MPa压差下驱油效果最好.在3 MPa驱替压差下开展了封窜提高采收率实验,封窜剂选用异丙胺.结果显示:封窜剂的残余阻力系数为6.92,扩大波及体积效果很好,提高采收率的幅度达15%.实验结果表明延长组长6段油藏的最佳驱替压差为10 MPa,在气窜之后采用异丙胺封堵能大幅提高最终采收率.In order to improve the development effect of ultra-low permeability reservoirs,based on the condition of the Chang-6 oil reservoir of Yanchang Formation in Jingbian Oilfield,five sets of immiscible CO2flooding experiments with different production pressure differences( 1 MPa,2 MPa,3 MPa,4 MPa,5 MPa) were carried out to analyze the channeling laws of CO2. The results show that with the increase of the pressure difference,gas breakthrough and gas channeling are all ahead of time,but the ultimate recovery rate first increases and then decrease,and that the gas breakthrough before and after,oil output sharply increases,so the period is important to the oil recovery. The experimental results also show that there is the best immiscible CO2flooding effect under the pressure difference of 3MPa. In order to enhance the oil recovery efficiency,using isopropylamine as plugging agent,the plugging channeling experiments are carried out under the pressure difference of 3 MPa. It is shown that,the residual resistance coefficient of the plugging agent is 8. 56,the plugging agent has good enlarging sweep volume effect,and oil recovery efficiency can be enhanced by 15%. It is also shown that the optimal flooding pressure difference of Chang-6 oil reservoir of Yanchang Formation is 10 MPa,and using isopropylamine as plugging agent could greatly improve the ultimate recovery efficiency after gas channeling.

关 键 词：CO2非混相驱油 气窜规律 封窜 异丙胺 波及体积 

分 类 号：TE357.4[石油与天然气工程—油气田开发工程]