埕岛油田埕北326A井组钻井液油层保护技术

Reservoir protection techniques of drilling liquid applied on Chengbei well group 326A,Chengdao oilfield

针对埕岛油田埕北326A井组施工中面临的油层保护技术难题,采用充填暂堵与防水锁剂并用的油层保护方案,通过处理剂优选实验,研制了优质无污染海水钻井液体系。性能评价实验结果表明,该钻井液体系抗粘土、抗盐、抗钙污染能力强,具有良好的流变性能。动态污染实验结果表明,岩心渗透率恢复率超过90%,油层保护效果较好。埕北326A井组现场应用结果证实,优质无污染海水钻井液体系性能稳定,能有效抑制泥页岩水化,全井组在钻井、完井过程中,井壁稳定,施工安全顺利。截至2010年8月26日,埕北326A-2和埕北326A-4井的产油量分别为92和68.6t/d,且油层保护效果好。

In response to the technical problems of protecting the reservoir from being damaged during the field application of well group 326A in Chengdao oilfield,the reservoir protection plan combining temporary filling plugging and anti-water-block agent is adopted,thereafter,the high quality non-pollution sea water drilling liquid system is proposed through handling agent screening experiment.The performance evaluation experiment reveals that this drilling liquid is high in anti-clay,anti-salt,anti-calcium and anti-pollution,therefore full of favorable rheology performance.The dynamic pollution experiment also exhibits that the core retrieving permeability is up to 90%,good reservoir protection performance.The field test on well group 326A of Chengbei oilfield verifies that the high quality non-polluted sea water drilling liquid is stable and may constrain the liquification of shale,that is, stable borehole in the whole drilling and well completion process.As of August,26,2010,the daily oil production of well 326A- 2 and 326A-4 is 92 and 68.6 t respectively with good reservoir protection performance.