低压低产气井井底净化处理剂研制及现场应用

Development and Field Application of Bottom Hole Cleaning Agent for Low Pressure and Low Production Gas Wells

低压低产气井井底污染原因复杂,井底净化效果不明显,本文通过井底污染类型的梳理,明确低压低产气井污染是水锁伤害、乳状液污染和结垢堵塞等多种污染共同作用的结果。针对性研制一种具有降低表面张力和改变储层润湿性的解除水锁处理剂,通过优选破乳剂和垢处理剂,研究形成能有效降低表面张力、改善储层润湿性、破乳及溶垢阻垢为一体的井底净化处理剂,处理剂表面张力25.66 mN·m^(-1),pH值6,能够使岩心接触角增加12.63°,针对ZJ122沙溪庙组岩心,返排24 h渗透率恢复率明显提高,溶垢阻垢能力强,破乳速度快,有利于提高井底净化效果。

The cause of bottom hole pollution of low pressure and low production gas wells is complex,and the bottom hole purification effect is not obvious.Through the carding of the types of bottom hole pollution,this paper makes it clear that the pollution of low pressure and low production gas wells is the result of water lock damage,emulsion pollution and scaling blockage.A kind of water lock release treatment agent is developed,which can reduce surface tension and change reservoir wettability.By optimizing demulsifier and scale treatment agent,a bottom hole purification treatment agent which can effectively reduce surface tension,improve reservoir wettability,demulsification and scale dissolving and scale inhibition ability is formed.The surface tension of the treating agent is 25.66 mN·m^(-1),pH 6,the treatment agent can increase the contact angle of core by 12.63°.Aiming at the core of ZJ122 shaximiao formation,the recovery rate of permeability in 24 hours is increased obviously,the ability of scale dissolving and scale inhibition is strong,and the speed of demulsification is fast,which is beneficial to improve the bottom hole purification effect.