低渗储层压驱设计数值模拟研究

Numerical simulation of pressure flooding design for low-permeability reservoirs

研究了室内驱替实验的岩心渗流特征及驱油规律,建立考虑压驱注水驱油机理的纯基质系统油藏数值模型,实现了考虑压驱过程基质渗透率变化的油藏压驱数值模拟方法。基于以上方法,研究了一般低渗、特低渗、超低渗油藏不同注入排量、注入总量、压驱时机、压驱方式、注采比对压驱增产的影响规律,明确不同压驱参数对油藏采油速度和最终采收率影响规律,初步给定储层最优的压驱工艺参数组合。

The seepage characteristics of the core and the rules of oil displacement in laboratory displacement experiments were studied.It was established a numerical model of a pure matrix system reservoir considering the mechanism of oil displacement by pressure-drive water injection,and it was realized a numerical simulation method of pressure flooding in reservoirs considering the change of matrix permeability in the process of pressure-driving.Based on the above method,the influences of different injection rates,total injection volume,pressure-drive timing,pressure-drive mode,and injection-production ratio on a pressure-drive production increase in general low-permeability,extra-low-permeability,and ultra-low-permeability reservoirs were studied.The influences of different pressuredrive parameters on the oil recovery rate and ultimate recovery efficiency were clarified,so that the optimal combination of pressuredrive parameters for the reservoir could be determined preliminarily.