致密油层空气泡沫驱油提高驱油效率实验研究

Experimental Study on Improving Oil Displacement Efficiency by Air-foam Flooding in Tight Oil Layer

商琳琳 许建红

SHANG Linlin，XU Jianhong

致密油层物性差，孔喉半径小，油藏非均质性严重，水驱驱油效率低，注水开发效果差。针对这些问题，为提高大庆外围龙虎泡油田高台子致密油层的驱油效率，模拟油层条件开展了空气-泡沫液体系驱油实验。结果表明，高台子致密油层水驱驱油效率平均值为48.95%，水驱后继续空气-泡沫液交替驱替的驱油效率为79.63%，驱油效率提高26.92%；小段塞交替驱替的效果好于大段塞驱；气液比过高，突破时间变短，驱油效率较低；用空气-泡沫液段塞驱代替水驱也能达到较好的驱油效果。致密油层水驱后转空气泡沫驱可大幅提高驱油效率，通过空气-泡沫液段塞、周期、气液比等注入参数的优化进一步改善致密油层驱油效果。图6表4参10

The tight oil layer had poor physical property，small pore throat radius，serious heterogeneity of reservoir，low water flooding efficiency，and poor effect of waterflood development. In order to further improve the oil displacement efficiency of Gaotaizi tight oil layer in Daqing oilfield，the experiment of air foam liquid system flooding was carried out by simulating the conditions of oil layer. The experiment results showed that the average oil displacement efficiency of water flooding in Gaotaizi tight oil layer was 48.95%，and the displacement efficiency of air-foam alternating flooding after water flooding was 79.63%，which increased the oil displacement efficiency by 26.92%. The displacement effect of a short alternating displacement was better than that of big slug. When the gas-liquid ratio was too high，the breakthrough time became shorter and flooding effect reduced. Instead of water flooding，direct air-foam liquid slug could achieve good flooding effect. The air-foam flooding could substantially improve the oil displacement efficiency of tight oil after water flooding. The displacement effect of tight oil layer could be improved through the injection parameter optimization of air-foam liquid slug，cycle and gas-liquid ratio.

10.19346/j.cnki.1000-4092.2019.03.020