高矿化度微泡沫钻井液技术的研究与应用

Study and Application of High Salinity Micro Foam Drilling Fluid Technology

江汉油田储层以上为盐膏层盖层,从减小油气层损害的角度考虑适宜用饱和盐水钻井完井液,但储层压力系数低,使用饱和盐水体系钻井易发生漏失。为此,对高矿化度微泡沫钻井液进行了研究。研制出了离子型起泡剂QP-1(主起泡剂)和非离子型起泡剂QP-2(辅起泡剂),并优选出了改性XC和PAC作抗盐型稳泡剂。利用JHPM全自动PVT实验仪测定了微泡沫钻井液在不同压力、温度下的密度变化情况,对其防漏堵漏能力进行了实验评价,分析了其防漏堵漏机理。该钻井液在觯深1井、拖26斜-2井等4口井中进行了实验应用。现场应用结果表明,该高矿化度微泡沫钻井液密度、黏度易于控制,在防漏堵漏方面具有特殊的优势,并提高了机械钻速。

A high salinity micro foam mud was adopted to drill the low pressure gradient salt and gypsum formations immediately above the reservoir which when drilled with saturated water base fluid,mud losses occurred frequently.Using biopolymer and poly anionic cellulose (PAC) as the foam stabilizer,an ionic foaming agent QP-1 (primary) and a non-ionic foaming agent (secondary) QP-2 were used to prepare micro foam muds evaluated using a JHMP automatic PVT tester at different pressures and temperatures for their densities.Also evaluated was their ability to control mud losses.Field application in wells such as PAISH- EN-1,TUO26XIE-2 showed that the density and viscosity of the foam mud were easy to control.The foam muds showed their advantages in mud loss control,and penetration rate was increased.