双段塞选择性堵水技术研究

油气井出水是油田开发过程中存在的一个普遍问题,给油气井生产、油气集输和油田开发,特别是注水开发的油田,带来严重的影响.选用水溶性的改性树脂-聚合物复合堵剂(DM-3)作为第一段塞,进行了大孔道裂缝型岩芯的堵水实验,发现堵剂对裂缝有较好的暂堵能力和选择性封堵能力,通过煤油浸泡24 h后,油解封率大于82.2%,具有良好的选择性,对地层伤害率低于25%,随着解封时间增长,解封率不断提高,暂时封堵率下降.通过一系列实验确定了高渗透性水泥段塞的粗粒径水泥配方,完成了施工性能的调节,在四川金华地区的金78井进行现场施工,取得了成功.

SELECTIVE WATER - PLUGGING TECHNOLOGY WITH COMPLEX-SLUG

The water production of the oil wells is a common problem in exploitation, which makes serious influences on production of oil wells, gathering and transportation of gas and oil, and the exploitation of oil fields recovered by water injection. The water plugging agent composed of altered-colophony-polymer (DM-3) is chosen as the first slug and water-shutoff experiments done on coarse pore-fracture cores. The result shows that this slug has good capability of temporary plugging and selective sealing on core. Dipping in diesel for 24 hours, the oil de-plugging is greater than 82%, and the formation damage is less than 25%, as the time of de-plugging gets longer, the de-plugging is getting better and temporary plugging decreases. The basic formulation of thick particle cement has been determined through a series of experiments. The adjustments of the operation function have been finished. Field operation in Well Jin78 in Sichuan Jinhua is successful.