低渗透油藏动态渗吸机理实验研究及数字岩心模拟

在低渗油藏的开发过程中,渗吸作用对于产量提升起到重要作用.传统的岩心渗流实验难以从微观的角度较为清晰地描述岩石物性、孔喉分布、岩石组分构成等特征.利用数字岩心技术建立孔隙网络模型,对真实岩心孔隙结构进行渗吸模拟分析具有重要意义.对松辽盆地某区域岩心样品通过综合微计算机断层扫描技术(micro computed tomography,Micro-CT)、数字岩心分析技术,实现低渗储层数字岩心渗吸过程的模拟,与实验室岩心自发渗吸实验对照,结果表明,利用数字岩心技术模拟得到的孔隙度、渗透率参数与实验室测量结果相差较小,提取的孔隙网络模型与真实岩心误差较小,从而可以保证数字岩心得到的两相渗流模拟结果具有较高的可信度,为油藏渗吸作用的机理研究提供了新的思路,对指导实际油藏开发具有重要意义.

Experimental study on dynamic imbibition mechanism of low permeability reservoir and digital core simulation

In the development process of low permeability reservoirs, the effect of spontaneous imbibition plays an important role in the enhancement of oil production recovery. The traditional core imbibition experiment is difficult to clearly describe the characteristics of petrophysical properties, pore throat distribution and rock composition from the microscopic perspective. The establishment of pore network model based on digital core technology is of great significance to simulate and analyze the spontaneous imbibition of real core. Few regional cores sample in Songliao Basin are used through integrated Micro-CT scan and digital rock technology to achieve the digital core spontaneous imbibition simulation, and laboratory core spontaneous imbibition experiment is used to compare, the results show that the parameters of porosity, permeability are little different between digital core technology simulation and laboratory measurements, the pore network model and the real core are of little error, which can guarantee the two phase flow simulation results of digital core has high credibility, and have significant guidance for the study of spontaneous imbibition effect and enhancement of the oil recovery.