重复压裂技术研究与应用

Research and Application of Refracturing Technology

银本才,杜卫平,陈小新

Yin Bencai , Du Weiping, Chen Xiaoxin

中原油田分公司井下特种作业处

Downhole Special Service Division, Zhongyuan Oilfield Company, SINOPEC, Henan 457001, P. R. China

针对中原油田油藏特点, 研究了低渗透油藏的老井重复压裂技术。运用压前评估技术, 提出了复压井选层原则, 同时研究了运用模糊数学方法进行选井选层。根据储层特点及上次失效原因, 提出了重复压裂时机的确定方法, 研究应用了提高复压效果的高砂液比施工技术。在此基础上进行了重复压裂优化设计, 根据实验室试验结果, 选用了有机硼交联改性胍胶水基压裂液体系及低密度高强度支撑剂。现场实施10 口井, 施工成功率100% , 有效率90% ,达到了稳油控水的目的, 对老油区的改造起到了积极作用, 展现了良好的应用前景。

Aimming at the characteristics of oil reservoirs in Zhongyuan Oilf ield, the refracturing technologies for old wells are researched. W ith assessment before fracturing, the principle of selecting layers for refracturing wells is provided, and a fuzzy mathematics method in selecting layers and wells is also used. On the base of reservoir characteristics and the last inefficiency reasons, a method of determining refracturing opportunity is put in, and the treating technique with high sand ratio to enhance fracturing effect is also studied. About that, optimum design of refracturing is done as well. Based on the lab-test results, modified guar gum water-base system crosslinked by organic bom agent, low-density and high-strength proppant are selected in a refracturing job. Through field application for 10 wells, the refracturing technology achieved obvious result in increasing production and controlling water cut with success percent of 100 and effective ratio of 90 percent. The technology has a positive effect in f racturing innovation for old blocks, showing its good prospect in the future.