纳米二氧化硅-壳聚糖杂化材料在水基钻井液中的应用研究

Application of nano-silica-chitosan hybrid material in water-based drilling fluid

首先制备了纳米二氧化硅-壳聚糖杂化材料,并利用傅里叶红外光谱(FT-IR),热重分析(TGA),动态光散射(DLS)和Zeta电位对产物进行了表征.此外,还将纳米二氧化硅,壳聚糖和纳米二氧化硅-壳聚糖杂化材料应用于水基钻井液中,进一步考察了其对于水基钻井液性能的影响.结果表明,相比于纳米二氧化硅和壳聚糖,纳米二氧化硅-壳聚糖杂化材料可有效增大水基钻井液的粘度,在2.0%的加量下可将水基钻井液的滤失量从25.2 mL降低至8.2 mL,降滤失效果显著.同时,还利用了扫描电镜(SEM)对上述几种水基钻井液的泥饼的微观形貌进行了分析,结果显示纳米二氧化硅-壳聚糖杂化材料可有效封堵泥饼的微裂缝,形成高质量的泥饼.这对于井壁稳定和减少钻井事故有着重要的意义.

Nano-silica-chitosan inorganic-organic hybrid materials are mainly used in drug control and the preparation of composite materials.However,its application in drilling fluids has rarely been reported.Nano-silica-chitosan hybrid materials were prepared and characterized by Fourier transform infrared spectroscopy(FTIR),thermogravimetric analysis(TGA),dynamic light scattering(DLS)and Zeta potential.In addition,nano-silica,chitosan and nano-silica-chitosan hybrid materials are also used in water-based drlling fluids.The results show that,compared with nano-silica and chitosan,nano-silica-chitosan hybrid material can effectively increase the viscosity of waterbased drilling fluid.The filtration loss of water-based drilling fluid can be reduced from 25.2 mL to 8.2 mL with 2.0%addition,and the effect of filtration reduction is significant.At the same time,the micro-morphology of mud cakes of these water-based drilling fluids was analyzed by scanning electron microscopy(SEM).The results show that nano-silica-chitosan hybrid material can effectively plug the micro-cracks of mud cakes and form high-quality mud cakes.It is of great significance for wellbore stability and reducing drilling accidents.