大庆西部稠油水平井蒸汽驱数值模拟研究

大庆西部斜坡江55区块油藏埋藏深度浅,油藏温度低,油层厚度比较薄,直井冷采产量很低,因此开发该油藏的比较可能的开采方式为水平井蒸汽驱和水平井蒸汽吞吐。为了改善其开发效果,针对水平井蒸汽驱,应用CMG数值模拟软件在三维地质建模的基础上对注采参数进行了优化。通过改变井距、水平段长度、采注比、蒸汽干度、注汽速度等生产参数,预测开发效果,对比生产效果确定合理的生产参数。结果表明:水平井水平段长度300 m时蒸汽驱总体效果比较好;蒸汽干度要达到0.4之上;蒸汽吞吐三周期之后转蒸汽驱效果最好;井距越大,采出程度越低;油层越厚,采出程度越高。

Numerical simulation on horizontal steam flooding of heavy oil in the west of Daqing

In view of characteristics of shallow buried depth, low reservoir temperature, small reservoir thickness and low production level of vertical cold production in Jiang55 block in the western slope of Daqing, so the probable methods of developing the reservoir are horizontal steam stimulation and horizontal steam flooding. To improve the development effect of horizontal well steam flooding, CMG numerical simulation software based on three-dimensional geological modeling is utilized to optimize injection and production parameters. Their respective development effects are predicted by changing production parameters such as well spacing, horizontal length, production injection rate, steam quality, steam injection rate etc, logical production parameters are determined by comparing production effects. Results indicate that the overall effect of steam flooding is better when horizontal length of horizontal well is 300m; steam quality is 0.4 at least; the effect is best when steam flooding is performed after three stimulation cycles; well spacing is bigger, recovery percentage is lower; oil reservoir is thicker, recovery percentage is higher.