低渗油藏注水井解堵增注技术研究

摘要

Some water injectors in the Zhuangxi low and extra - low permeability reservoirs are confronted with problems of high injection pressure (44 Mpa) , under - injection and poor injection response, as well as short life and low efficiency with conventional acid fluid systems. Laboratory experiment has been conducted on compound technology of decompression and augmented injection with sandstone acid - bioactivator. The experiment result indicates that the compound is highly functional as a retarding agent, corrosion inhibitor and in - depth block remover. The new activator can effectively reduce surface tension, change formation wettability, reduce pressure and augment injection. The technology provides guarantee for in - depth acidization and injection stimulation in water injectors and is of important significance to improving water flooding response in low and extra - low permeability reservoirs.%为了解决桩西低渗、特低渗油藏部分注水井注水压力过高(44MPa)、欠注严重、注水效果差,以及常规酸液体系有效期短、效果差等难题,对砂岩酸-生物活性剂复合降压增注技术进行了室内实验研究.实验结果表明,该项技术具有良好的缓速缓蚀深部解堵功能,其新型活性剂可有效降低表面张力,改变地层润湿性,降压增注.该技术为注水井深部酸化增注提供了可靠的技术保证,对改善低渗、特低渗油田的注水开发效果具有十分重要的意义.