渗透率各向异性油藏的开发对策研究

DEVELOPMENT COUNTERMEASURES RESEARCH FOR PERMEABILITY ANISOTROPY RESERVOIRS

渗透率各向异性是储层、尤其是河流相储层的基本性质,它对油藏的有效开采会产生一定的负面影响。在注水保持地层能量的开发过程中,注入流体沿高渗透率方向优先推进,导致不同方向上的生产井见水时间差别较大,致使驱替过程很不均衡,从而影响油藏开发效果。针对上述问题,基于渗流力学理论,提出了井距控制法和注采压差控制法两种应对措施,并用数值模拟方法检验了这两种对策的有效性。验证结果表明,井距控制法和注采压差控制法能促使注入流体在储层中的均衡驱替,因而能保证不同方向上的油井见水时间的一致性,从而可以有效地抑制渗透率各向异性的负面影响。

Permeability Anisotropy is an essential property for the formation,especially for the formation of fluvial facies.And this property would lead to some negative influence upon the efficient development of reservoir.During the reservoir development,with retaining the formation energy by water injection,the injection fluid preferentially flowed along the high permeability direction,and this would cause that the water breakthrough times for production wells in different directions were different obviously from each other,and result in the unbalanced displacement,consequently influence the effects of reservoir development.The countermeasures,which were called wellspacingcontrol method and the injectionproduction pressure difference control method,were put forward on the basis of the percolation mechanics theory for the above problem.Then the validation of the two methods was verified by numerical reservoir simulations.The test results demonstrated that the two methods could both help to bring about the balanced displacement of injection fluid,and thus could ensure the consistency of the waterbreakthrough times for the oil wells in different directions,accordingly they could restrain the negative influence of the permeability anisotropy.