注水井压裂调剖设计方法研究

DESIGEN METHOD FOR FRACTURED INJECTION WELL PROFILE MODIFICATION

对于低渗透油田 ,主要通过水力压裂提高油水井的增产增注能力 ,区块经过整体压裂改造后 ,水力裂缝参数将对油水井的产量起决定性作用。对于多油层非均质油藏 ,层间差异会导致吸水剖面不均匀 ,影响水驱效率。对需要经过压裂再投注的注水井 ,建立了压裂后预测注水井注入量的数值模型 ,分析了各层注入量与地层物性、裂缝参数和注入压力的关系。研究结果表明 ,通过合理地设计裂缝参数 ,可以减缓层间矛盾 ,改善吸水剖面。现场试验 8口井 ,其中 6口井进行了吸水剖面测试 ,全井达到配注方案的有 4口井 ,说明该方法对多油层非均质油藏注水井的调剖具有一定的应用价值。

As for low permeability reservoir, it is mainly by hydraulic fracturing to improve injection production capability of wells and keep formation pressure. After block integral reconstruction by fracturing, the fracture parameters arc the decisive factors influencing the production injection rate of the wells. In multilayer heterogeneous reservoir, the interlayer difference would lead to nonuniformity of injection profile and influence water displacement efficiency. For the injection well which needs fracturing, a simulation model of injection prediction of fractured well is constructed in this paper. The relations among injection and formation properties, fracture parameters,injection pressure are analyzed. The results show that the interlayer contradiction can be reduced and the injection profile can be improved by reasonal design of different fracture parameters for fractured injection well. Injection profiles of six wells are tested, and four wells have completely reached the level of injecting scheme. It is shown that the method is practically use fill to injection profile modification of injection well in multizone heterogeneous reservoir.