低渗非均质油藏CO_2驱特征及水动力学封窜方法
|
摘要
CO_2注入油藏不仅可以大幅度提高原油采收率,且可以实现温室气体减排的目标。因此,CO_2驱技术得到越来越广泛的应用。我国油藏多属于陆相沉积,非均质严重,导致CO_2气窜严重,使CO_2驱油效果变差。利用层内非均质模型,开展了连续注气、水气交替、间歇注气和脉冲注入CO_2开采模拟实验,研究了非均质油藏CO_2驱开采驱特征及动力学环境对CO_2气窜的影响。实验结果表明:水气交替注入驱油效果最好,间歇注气和连续注气效果次之,脉冲注气效果最差;CO_2驱未见气和低气油比阶段采出程度高,是主要的生产阶段,延长两个阶段的生产时间可以提高开发效果;通过改变水动力学条件可以有效地抑制CO_2气窜,水气交替注入抑制气窜能力较强,而脉冲注气的扰动效应加剧了模型中CO_2气窜,上述实验结果表明非均质油藏水气交替注入是CO_2驱最优注入方式。
CO_2 injection is a commonly used technique for recovering oil from mature reservoirs as it can not only greatly improve oil recovery, but also achieve the goal of greenhouse gas emission reduction. Most of the reservoirs in China are continental deposits, and the serious heterogeneity leads to serious CO_2 gas channeling, which makes the effect of CO_2 flooding worse. In this paper,the simulation experiment of continuous gas injection, WAG, intermittent gas injection and pulse injection of CO_2 is carried out by using the heterogeneous model in the layer, and the effects of the characteristics of the CO_2 flooding in the heterogeneous oil reservoir and the dynamic environment on the CO_2 gas blow-by are studied. The experimental results show that WAG injection flooding is the best, the effect of intermittent gas injection and continuous gas injection is second, and the pulse gas injection effect is the worst; CO_2 flooding has no gas and low gas oil. In the production stage, extending the production time of the two stages can improve the development effect; by changing the hydrodynamic conditions, the CO_2 gas channeling can be effectively suppressed, and the WAG injection is more capable of suppressing the gas channeling, and the disturbance effect of the pulse gas injection is intensified. The above experimental results show that WAG injection in heterogeneous reservoirs is the optimal injection mode for CO_2 flooding.
CO_2 injection is a commonly used technique for recovering oil from mature reservoirs as it can not only greatly improve oil recovery, but also achieve the goal of greenhouse gas emission reduction. Most of the reservoirs in China are continental deposits, and the serious heterogeneity leads to serious CO_2 gas channeling, which makes the effect of CO_2 flooding worse. In this paper,the simulation experiment of continuous gas injection, WAG, intermittent gas injection and pulse injection of CO_2 is carried out by using the heterogeneous model in the layer, and the effects of the characteristics of the CO_2 flooding in the heterogeneous oil reservoir and the dynamic environment on the CO_2 gas blow-by are studied. The experimental results show that WAG injection flooding is the best, the effect of intermittent gas injection and continuous gas injection is second, and the pulse gas injection effect is the worst; CO_2 flooding has no gas and low gas oil. In the production stage, extending the production time of the two stages can improve the development effect; by changing the hydrodynamic conditions, the CO_2 gas channeling can be effectively suppressed, and the WAG injection is more capable of suppressing the gas channeling, and the disturbance effect of the pulse gas injection is intensified. The above experimental results show that WAG injection in heterogeneous reservoirs is the optimal injection mode for CO_2 flooding.
引文
[1]刘炳官,朱平,雍志强,等.江苏油田CO2混相驱现场试验研究[J].石油学报,2002,23(4):56-60.
[2] J R Christensen, E H Stenby, A Skauge. Review of WAG field experience[C]//paper SPE-39883-MS presented at the International Petroleum Conference and Exhibition of Mexico, 3-5 March1998, Villahermosa, Mexico.
[3]李兆敏,张超,李松岩,等.非均质油藏CO2泡沫与CO2交替驱提高采收率研究[J].石油化工高等学校学报,2011,24(6):1-5.
[4]赵金省,谭俊领,古正富,等.非均质储层CO2泡沫调驱注人参数优化实验研究[J].中国工程科学,2012,14(11):88-93.
[5]杨昌华,王庆,董俊艳,等.高温高盐油藏CO2驱泡沫封窜体系研究与应用[J].石油钻采工艺,2012,34(5):95-97.
[6] Jianhang Xu, Aaron Wlaschin, Robert M Enick. Thickening carbon dioxide with the fluoroacrylate-styrene copolymer[C]//paper SPE-71497-MS presented at the SPE Annual Technical Conference and Exhibition, 30 September-3 October 2001, New Orleans, Louisiana, USA.
[7] R M Enick, D Olsen, J Ammer, et al. Mobility and conformance control for CO2EOR via thickeners, foams, and gels--a literature review of 40 years of research and pilot tests[C]//paper SPE-154122-MS presented at the SPE Improved Oil Recovery Symposium, 14-18 April 2012, Tulsa, Oklahoma, USA.
[8]沈爱国,刘金波,佘跃惠,等.CO2潜在增稠剂苯乙烯醋酸乙烯酯二元共聚物的设计与合成[J].石油天然气学报,2011,33(2):131-135.
[9]徐阳,赵仁保,王淼,等.CO2驱封窜用新型复合凝胶体系筛选评价研究[J].石油天然气学报,2010,32(1):346-351.
[10]王锐,岳湘安,王春旭,等.压力和电场对低渗油藏基质中采收率的影响[J].大庆石油地质与开发,2009,28(6):130-135.
[2] J R Christensen, E H Stenby, A Skauge. Review of WAG field experience[C]//paper SPE-39883-MS presented at the International Petroleum Conference and Exhibition of Mexico, 3-5 March1998, Villahermosa, Mexico.
[3]李兆敏,张超,李松岩,等.非均质油藏CO2泡沫与CO2交替驱提高采收率研究[J].石油化工高等学校学报,2011,24(6):1-5.
[4]赵金省,谭俊领,古正富,等.非均质储层CO2泡沫调驱注人参数优化实验研究[J].中国工程科学,2012,14(11):88-93.
[5]杨昌华,王庆,董俊艳,等.高温高盐油藏CO2驱泡沫封窜体系研究与应用[J].石油钻采工艺,2012,34(5):95-97.
[6] Jianhang Xu, Aaron Wlaschin, Robert M Enick. Thickening carbon dioxide with the fluoroacrylate-styrene copolymer[C]//paper SPE-71497-MS presented at the SPE Annual Technical Conference and Exhibition, 30 September-3 October 2001, New Orleans, Louisiana, USA.
[7] R M Enick, D Olsen, J Ammer, et al. Mobility and conformance control for CO2EOR via thickeners, foams, and gels--a literature review of 40 years of research and pilot tests[C]//paper SPE-154122-MS presented at the SPE Improved Oil Recovery Symposium, 14-18 April 2012, Tulsa, Oklahoma, USA.
[8]沈爱国,刘金波,佘跃惠,等.CO2潜在增稠剂苯乙烯醋酸乙烯酯二元共聚物的设计与合成[J].石油天然气学报,2011,33(2):131-135.
[9]徐阳,赵仁保,王淼,等.CO2驱封窜用新型复合凝胶体系筛选评价研究[J].石油天然气学报,2010,32(1):346-351.
[10]王锐,岳湘安,王春旭,等.压力和电场对低渗油藏基质中采收率的影响[J].大庆石油地质与开发,2009,28(6):130-135.