任11碳酸盐岩油藏注CO_2提高采收率研究

Study on EOR by carbon Dioxide Injection Process in R11 Carbonate Reservoir

许多碳酸盐岩油藏进入高含水开发期,如何挖潜,进一步提高采收率是目前的主要工作方向。目前任11碳酸盐岩油藏存在单井产油量低,注入水利用系数低,水驱效率越来越差的问题。因此需要探索新途径,以便进一步发挥油藏生产潜力。分析了任11油藏注CO2提高采收率的机理,开展了任11油藏注CO2提高采收率的数值模拟研究。针对研究区块的地质及开发特点,建立了相应的三维数值模型,在水驱历史拟合的基础上,应用数值模拟技术从注气强度、注气方式、注气部位,生产气油比控制等方面进行了优化研究。油藏注CO2方案模拟计算20年,产油量显著上升,采用注CO2可比目前开发方式提高采收率3.5%左右。

Many carbonate reservoir have been into high water-cut development stage. How to dig the remaining oil potential and enhancing oil recovery further is dominant work target now. There are many problems in carbonate reservoir of RI i, such as low oil production of single well, inefficient utilization of injected water, and worsening of the water-flood efficiency. Therefore it is necessary to find a new way to dig reservoir production potential. The EOR mechanism by Carbon dioxide injection process in R11 is analyzed and the numerical simulation research on EOR by Carbon dioxide injection process in R11 reservoir is completed. Aimed at reservoir properties and development characteristic the three-dimensional numerical model is set up. Based on the fitting history of water flooding, the gas injection rate, gas injection mode, gas injection position and the gas-oil ratio control are optimized. The plan of Carbon dioxide injection is predicted for 20 years and the result shows that oil production rise obviously and it can enhance oil recovery about 3.5% more than the current exploitation mode.