稠油热采井氮气泡沫调剖技术研究与应用

Study and application on nitrogen-foam profile control technique in thermal recovery well for heavy oil

针对河南稠油热采井的汽窜问题,开展了氮气泡沫调剖技术体系的室内实验及参数优化研究,通过发泡剂的静态性能评价和单双管连续驱替实验,确定了最佳发泡剂质量分数和最佳气液比,优选发泡剂质量分数为0.5%,推导出最佳气液比在地面条件下注氮气量与蒸汽量之比约为40:1左右,单井汽窜的泡沫调剖段塞注入量为0.1 PV左右。2007年,经过现场7口井的氮气泡沫调剖试验,措施有效率85.7%,取得了较好的增油效果,措施后平均单井注汽压力与措施前相比上升0.6 MPa,有效封堵了热采井的汽窜通道。

Laboratory experiment and parameters of nitrogen- foam profile control technique are conducted to solve the steam breakthrough in thermal recovery well for dense oil in Henan oil field.Through the static performance evaluation and consecutive single and dual string displacement experi- ment,the optimal mass fraction of foaming agent and the op- timal gas liquid ratio are obtained:the mass fraction of foa- ming agent as 0.5%;the deduced optimal ratio of nitrogen and steam production under the ground condition as about 40 :1;and the injection amount in the foam profile control see- tion of individual well of steam breakthrough as about 0. 1PV.In 2007,through experiments of nitrogen- foam pro- file control in 7 wells,a success ratio of measure as 85.7 is acquired and the steam injection pressure of individual well after measure increased by 0.6MPa,which effectively block the steam breakthrough channel of thermal recovery well.