一种抗高温高密度水基钻井液体系的优选及室内评价研究

Selection of A Water-based Drilling Fluid System of High-temperature Resistance and High Density and Its Laboratory Evaluation

针对深井、超深井温度和压力高,地层结构复杂等因素,结合深井钻井液的技术特点,通过对抑制剂、抗高温稳定剂、抗高温降滤失剂、抗高温增黏剂、润滑剂等添加剂的优化, 研制了-套密度在1.80～2.20g/cm3 可调、具有现场可操作性的抗高温高密度水基钻井液体系HTDF,其配方如下4%膨润土＋0.1%NaOH＋0.5%乙醇胺＋0.5%PADS＋3%CSMP-2 （视博）＋3%SPR （视博）＋0.2%KPAM＋0.3%PAMS＋1.5%TEX＋重晶石,并对其高温稳定性、抗污染性、抑制性、润滑性、油层保护性和高温高压滤失性能等进行了室内评价.结果表明,该体系具有长时间的抗温稳定性（抗200℃）,能有效抑制泥岩的水化膨胀,具有较强的封堵性,滤失量低,对储层伤害小,可以满足钻进时工程地质要求.

In consideration of the problems of high temperature and high pressure and the complex formation structures of deep and ultra-deep wells,combined with the technical characteristics of deep well drilling fluid,a set of water-based drilling fluid systems of high temperature and high density are developed by optimizing the inhibitive agent,high temperature stabilizer,high temperature fluid loss additives,high temperature viscosifier and lubricity,it has an adjustable density between 1.80~2.20g/cm3,it is a water-based drilling fluid system of high-temperature resistance and high density(HTDF)and it has field operability.The formula includes 4% bentonite+0.1% NaOH+0.5%ethanolamine+0.5% PADS+ 3%CSMP-2+3%SPR+0.2%KPAM+0.3%PAMS+1.5%TEX+ barite.And its high temperature stability,pollution resistance,inhibitory,lubricity,reservoir protection and high temperature and high pressure filtration are evaluated in laboratory.The results show that the system has a long time of temperature resistance(200℃)with the strong sealing ability,low filter loss,little damage to the reservoir,it can prevent and control the hydration of mudstone effectively and meet the engineering geological requirements of drilling.