尕斯油田E_3~1油藏复合深部调剖技术应用实践

Application of the Compound Indepth Profile Modification in Gasi Oilfield E_3~1 Reservoir

针对青海尕斯油田E31油藏高温高矿化度条件(温度126℃,地层水矿化度174501 mg/L),进行"预交联颗粒+可动凝胶"复合深部调驱体系室内研究和现场应用。实验结果表明,所用颗粒在模拟地层水中的膨胀倍数达到了10倍以上;聚合物/复合交联剂可动凝胶体系具有较好的抗盐抗温性能;岩心驱替实验结果表明,预交联颗粒优先进入高渗透层并封堵大孔道,后续注入的可动凝胶主要进入低渗透层,启动低渗透层的原油,达到深部调剖驱油的功能,在高渗与低渗填砂管中,采收率在水驱基础上分别提高了12.97%和29.72%。该油藏复合调驱现场应用实践表明,两个井组累计增油4498.35 t,累计减少产水11009.49 m3,复合调驱技术的成功应用为高温高矿化度油藏控水增油技术推广提供了一定参考依据。

Aimed at the high temperature and high salinity conditions（temperature 126℃,formation water salinity 174501mg/L） of Gasi oilfield E31 reservoir,the laboratory study and field application of the compound in-depth profile modication system ＂the pre-crosslinked gelled particle ＋ movable gel＂ were carried out.The pre-crosslinked gelled particles could swell by 10 times after saturated by model water,and the movable gel had excellent tolerance to temperature and salinity.The core flowing experiment showed that the pre-crosslinked gelled particles were inclined to enter the higher permeable layers and to block them,while the movable gel could enter the lower permeable layers to displace the crude oil,which resulted in realizing the function of the in-depth profile modification.The oil recovery in higher and lower permeable layers were enhanced by 12.97% and 29.72% based on the water-flooding,respectively.The movable gel used in field was 2000 mg/L polymer ＋1.0% crosslinking agent.The field application of the compound in-depth profile modification at two well groups indicated that the accumulation production of oil increased by 4498.35 tons and the accumulation production of water reduced by 11009.49 m3.The successful application of the compound in-depth profile modification technique provided reference to the widely use of the technology of controlling water and increasing oil for the high temperature and high salinity reservoir.