非均质油层空气泡沫驱提高采收率试验研究

Experiment Study of Improved Oil Recovery through Air Foam Flooding in Heterogeneous Reservoir

中原油田胡12区块是一主力区块，由于油层非均质性强．导致注水开发后油井含水上升速度快，水淹严重，油藏采收率低。为进一步提高油藏采收率，达到降水稳油的目的，模拟其油层条件。建立了非均质油层模型．以廉价的空气为基础，进行了空气泡沫驱油提高采收率室内试验，主要进行了不同注入方式、不同气液比对采收率影响的试验。试验结果表明，发泡剂、空气交替注入。发泡剂、空气、水交替注入，泡沫、空气交替注入3种注入方式中，泡沫、空气交替注入方式效果最好；气液比在1：1～3：1范围变化时，最佳气液比为3：1。试验结果证明了空气泡沫驱能大幅度提高胡12区块油藏采收率，适用于高含水、非均质油藏，是一种有前途的三次采油方法．

Hu-12 block is a main reservoir in Zhongyuan Oilfield. Water cut increased sharply and caused severe water flooding and low oil recovery due to high reservoir heterogeneity. For the purpose of further improving oil recovery, reducing water cut and stabilizing oil production rate, a heterogeneous reservoir simulation model was created. Experiment study of air- foam flooding was conducted with focusing on the impact of different injection module and different gas- liquid ratio on the recovery. The results show thai the injection of foam alternating air is better than injection of alternating foam, air and water, and injectton of foam agent alternating air. The optimum gas- liquid ratio is 3 ： 1 in the range from 1 ： 1 to 3 ： 1. The experiment results suggest that the oil recovery of Hu-12 block was improved remarkably by air- foam flooding, which is applicable to heterogeneous reservoirs with high water cut. Therefore air- foam flooding is a promising tertiary oil recovery technique.