Nano-laponite/polymer composite as filtration reducer on water-based drilling fluid and mechanism study

In drilling deep complex formations, most drilling fluid additives have insufficient temperature and salt tolerance, resulting in the decline of drilling fluid performance. This study used 2-acrylamide-2-methylpropane sulfonic acid, acrylamide, dimethyl diallyl ammonium chloride, and modified nano-laponite to synthesize a nanocomposite filtrate reducer (ANDP) with excellent temperature and salt resistance, which can maintain the performance of drilling fluid. The structure of ANDP was analyzed by a transmission electron microscope and an infrared spectrometer. The thermal stability of ANDP was studied by thermogravimetric analysis. The performance of ANDP was evaluated in a water-based drilling fluid. The mechanism was analyzed per clay-particle size distribution, Zeta potential, filter cake permeability, and scanning electron microscopy imaging. The results show that ANDP has good thermal stability and expected molecular structure. The filtration of freshwater drilling fluid after agin...在深部复杂地层钻井过程中，多数钻井液添加剂的耐温抗盐性能不足，导致钻井液性能出现衰减。本研究以2-丙烯酰胺-2-甲基丙磺酸（2-acrylamide-2-methylpropane sulfonic acid）、丙烯酰胺（acrylamide）、二甲基二烯丙基氯化铵（dimethyl diallyl ammonium chloride）以及改性纳米锂皂石（modified nano-laponite）为原料，合成了一种耐温抗盐性能优异的纳米复合降滤失剂（ANDP），可有效维持钻井液性能。通过透射电子显微镜（transmission electron microscope）与红外光谱仪（infrared spectrometer）对ANDP的结构进行了表征分析，采用热重分析（thermogravimetric analysis）研究了ANDP的热稳定性能，并在水基钻井液（water-based drilling fluid）中评价了ANDP的应用性能。从黏土粒径分布、Zeta电位（Zeta potential）、滤饼渗透率以及扫描电子显微镜成像（scanning electron microscopy imaging）等角度对其作用机理进行了分析。结果表明，ANDP具备良好的热稳定性与预期的分子结构，老化后淡水钻井液的滤失量……