SDBS/Na2CO3改性膨润土及其在钻井液中的应用研究

SDBS/Na2CO3 modified bentonite and application in drilling fluid

对钙基膨润土经过钠化改性,其胶结性、悬浮性、分散性均得到提升,在水介质中,触变性较好,凝胶结构稳定,应用于钻井液中表现良好。实验考察了磁力搅拌时间、微波时间及功率、温度、十二烷基苯磺酸钠/碳酸钠(SDBS/Na2CO3)比例及50%无水乙醇等因素对膨润土改性的影响。得到制备改性膨润土最佳条件:m(膨润土)∶m(SDBS)∶m(Na2CO3)=16∶2∶3,50%无水乙醇40mL,磁力搅拌时间3min,微波时间2min,反应温度40℃,微波功率200W;将其用于制备钻井液,配方为:5%碳酸钠+4%改性膨润土+0.7%FLA+2%聚乙二醇+3%硅酸钾+0.8%硫酸钡,并对体系的流变性、滤失性、抑制性及抗污染性进行评价。

The cementation,suspension and dispersibility of calcium bentonite were improved by sodium modification.In water medium,thixotropy and fluidity are good,and it is easy to form a stable gel structure,which performs well in drilling fluid.The influences of magnetic stirring time,microwave time,power,temperature,SDBS/Na2CO3 ratio and 50% anhydrous ethanol on the natrified bentonite were investigated.Get the best preparation conditions of modified bentonite:the quality of m (bentonite)∶ m (SDBS)∶ m (Na2CO3) for 16 ∶2 ∶3,40 mL of 50% ethanol,magnetic stirring time of 3 min and 2 min,microwave time,reaction temperature 40 ℃,microwave power 200 W.Drilling fluid was prepared by using modified bentonite.The formula was:5% sodium carbonate +4% modified bentonite +0.7%FLA+2% polyethylene glycol +3% potassium silicate +0.8% barium sulfate.At the same time,the rheological,filtration,inhibition and pollution resistance of the system were evaluated.