摘要
非均质油藏各层的渗透率和孔隙结构不同,当有效压力变化时每一层的渗透率压敏性也不同,这必然会影响注入流体的分布。利用并联岩心模型,对低渗透非均质油藏的CO2驱开发过程进行了研究,分别讨论了渗透率和渗透率级差与有效压力的关系以及有效压力对流体分布的影响。研究结果表明,有效压力变化后,不同渗透率的岩心其渗透率压敏性不同,低渗透岩心渗透率压敏性比高渗透岩心的强;有效压力增加,渗透率级差变大,非均质性增强,高渗透岩心中分流率增加,低渗透岩心中分流率减少,波及体积减小。因此,在低渗透非均质油藏开发过程中应该保持合理的地层压力,尽量避免因压敏性而导致的波及体积减小的现象。
Because of the difference of permeability and pore configuration among the layers of heterogeneous reservoir,when the effective pressure changed,the sensitivity of each layer is different,which will certainly influence the distribution of the injected fluid. The stress sensitivity of the low heterogeneous reservoir and its influences on fluid distribution were researched using the parallel core model. The relationship between permeability and effective stress,permeability contrast and effective stress,fluid distribution and effective stress was mainly analyzed according to experiments. Cores with different permeability showed different stress sensitivity when effective stresses were modified,and lower permeability cores showed stronger stress sensitivity than high and moderate permeability ones. With the effective stress increasing,the parameters such as permeability contrast,heterogeneities and throughput ratios in high permeability cores all showed increasing tendencies,while throughput ratios in low permeability cores and swept volume decreased. So,formation pressure should be rational at the development process of low-permeability and heterogeneous oil reservoirs,then the decreased swept volume results from the stress sensitivity would be avoided.
<Keywords>heterogeneities ;permeability contrast ;effective stress ;stress sensitivity ;fluid distribution
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2009年第5期92-94,共3页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项"大型油气田及煤层气开发"之"复杂油气田地质及提高采收率技术"(2008ZX05009)
关键词
非均质
渗透率级差
有效压力
压敏性
流体分布
heterogeneities
permeability contrast
effective stress
stress sensitivity
fluid distribution
