深层低渗稠油有效开发方式

Effective Method for Development of Deep Heavy Oil in Low Permeability Reservoir

超深层低渗稠油油藏具有地层压力高、原油粘度高以及渗透率低等特点,常规注蒸汽热采降粘效果差、单井产能低,油藏开发难度极大。物模实验及数值模拟计算表明:开发初期高地层压力条件下采用CO2吞吐,后期地层压力下降转为DCS协同作用可有效解决深层低渗稠油降粘困难的问题;压裂改造可大幅度降低低渗导致的高启动压力梯度,有效提高稠油在油藏中的渗流能力。压裂辅助CO2吞吐开发方式在矿场应用中取得了良好效果。

High reservoir pressure,high viscosity and low permeability are main characters of deep heavy oil in low permeability reservoir. Reducing viscosity by the method of injecting steam has poor effect,so reservoir development faces great difficulty. Lab experiment and numerical simulation shows that combining CO2 soak at high reservoir pressure and DCS at low pressure can reduce oil viscosity effectively. Hydraulic fracturing can reduce threshold pressure gradient and improve percolation capacity. CO2 soak assisted by hydraulic fracturing made a good result in oilfield development.