千12块稠油油藏转氮气泡沫驱研究

Study on converting to nitrogen foam flooding for heavy oil reservoirs in Qian12 block of Liaohe oilfield

为改善辽河油田千12块莲花油层稠油油藏蒸汽吞吐和水驱的开发效果,开展了氮气泡沫驱提高采收率数值模拟研究。选取该区块主力断块千22块建立三维地质模型,在历史拟合的基础上,对氮气泡沫驱注采参数进行优化设计,并进行生产指标预测。研究结果表明,周期氮气泡沫驱比连续泡沫驱效果好,最佳注采参数为:注泡沫2个月,然后开井生产4个月为1个周期,单井注液速度为50m3/d,最佳气液比为1:1至1.5:1.0之间,最佳泡沫剂质量浓度为0.5%。该块采用氮气泡沫驱技术可以较好地改善稠油开发效果,达到降水增油和提高原油采收率的目的。

Numerical simulation of nitrogen foam flooding is conducted in order to improve the development effect of cyclic steam stimulation and water flooding in Lianhua heavy oil reservoirs of Qian12 block of Liaohe oilfield.A 3-D geological model is established for Qian22 fault block,the principal block in this area.The injection-production parameters are optimized and the production index is predicted for nitrogen foam flooding based on history match.The result shows that cyclic nitrogen foam flooding is better than continual foam flooding.The optimal injection-production parameters are:foam injection for 2 months and production for 4 months,which make up a cycle,with single well injection rate of 50 m3/d,gas-liquid ratio between 1:1 to 1.5:1,and foam agent mass concentration of 0.5%.Nitrogen foam flooding can improve heavy oil development effect,decrease water cut,and increase oil production and recovery factor for this block.