复杂油藏开发中的能量保持研究

对于边底水驱油藏、应力敏感油藏与高油气比油藏等复杂油藏,如果地层能量保持不适当,将会改变储层的渗流特征,显著降低油藏的采收率和开发效益。在深入研究复杂油藏生产特征的基础上,根据渗流理论阐述了边底水驱油藏水侵对储层的伤害、高油气比油藏脱气对渗流的影响、应力敏感油藏在较大应力下对渗流的影响,同时分析了其影响程度与地层能量保持的相互关系。在此基础上,提出了复杂油藏能量优化控制措施:对于边底水驱油藏,可以通过控制采油速度与产量、采用合理的井型及控制地层能量,改善油藏渗流特征,促进油藏的高效开发;对于应力敏感油藏和高油气比油藏,可以通过采用合理的井型、适时注水、采用合理的开采速度、改善油藏的渗流特征,提高采收率。

Study on the energy maintenance during the development of the complex reservoir

If the reservoir pressure wasn't properly maintained in the process of oil development,the character of fluid flow through porous medium will be changed,the recovery rate and the benefit of developing would obviously be declined for many types of reservoirs,such as water drive reservoir,high gas/oil ratio reservoir and stress-sensitive reservoir.Based on researching the production characteristic of the complex reservoir,It is elaborated that the energy maintenance has close relation with the formation damage caused by water invasion in water drive reservoirs,degasification in high gas/oil ratio reservoirs,and permeability decline in stress-sensitive reservoirs.Based on the above-mentioned study,corresponding energy maintenance schemes is presented for these complex reservoirs:It will promote the development of high efficiency to the water drive reservoir by proper draw down pressure and compatible well types;It will promote the development of high efficiency to the high gas/oil ratio reservoir and stress-sensitive reservoir by flooding in good time,proper draw down pressure,compatible well type and reasonable oil production rate.