超低渗透油藏N2吞吐提高采收率影响因素  

Factors of Influencing Enhanced Oil Recovery of N2 Huff-Puff in Ultra-Low Permeability Oil Reservoir

作　　者：王选涛 王海华 李秉路 苗伟 付明 张桐 WANG Xuantao;WANG Haihua;LI Binglu;MIAO Wei;FU Ming;ZHANG Tong(Sixth Oil Production Plant,PetroChina Changqing Oilfield Company,Xi'an,Shaanxi 710000,China)

机构地区：[1]中国石油长庆油田分公司第六采油厂,陕西西安710000

出　　处：《西安石油大学学报（自然科学版）》2020年第6期60-64,共5页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家科技重大专项“超低渗透油藏有效开采技术”(2011ZX05013-004)。

摘　　要：通过一系列室内N2吞吐物理模拟实验,对长庆超低渗透油藏N2吞吐提高采收率效果及其影响因素进行研究。结果表明:随吞吐周期增加,累计采收率逐渐增大,但增加幅度逐渐降低,经过5个吞吐周期,累计采收率提高8.30%~11.58%,其中前3周期,注气利用率高,吞吐效果较好;放喷压力越低,最终累计提高采收率越大,且放喷压力为6 MPa时注气吞吐效果最佳;适当增加焖井时间,能有效提高N2吞吐采收率;渗透率越高,周期采收率越大,吞吐效果越好。N2吞吐能有效提高超低渗透油藏采收率,但吞吐周期应控制在3个以内。The enhanced oil recovery effect of N2 huff-puff and its influencing factors in Changqing ultra-low permeability reservoir were studied through a series of laboratory simulation experiments of N2 huff-puff.The results show that the cumulative recovery efficiency increases gradually with the increase of the huff-puff cycle,but the increment decreases gradually.The cumulative recovery efficiency increases by 8.30%~11.58%by 5 huff-puff cycles,of which the first three cycles have high gas injection utilization rate and the huff-puff effect is better.The lower the production pressure,the greater the final cumulative recovery efficiency,and gas injection effect is the best when the production pressure is 6 MPa.Increasing the soaking time appropriately can effectively improve the recovery efficiency of N2 huff-puff.The higher the permeability of reservoir,the greater the cycle recovery efficiency and the better the N2 huff-puff effect.N2 huff-puff can effectively improve the recovery efficiency of ultra-low permeability reservoir,but the huff-puff cycle number should be controlled within three cycles.

关 键 词：N2吞吐 提高采收率 吞吐周期 放喷压力 焖井时间 超低渗透油藏 

分 类 号：TE357[石油与天然气工程—油气田开发工程]