钻井液用抗高温低分子增稠剂的制备及性能评价

Preparation and performance evaluation of an anti-high temperature low-molecular-weight thickener for drilling fluid

为了保持钻井液在高温条件下具有良好的流变性、改善沉降稳定性,以丙烯酰胺、丙烯酸为原料,引入2-丙烯酰胺基-2-甲基丙磺酸、N-乙烯基吡咯烷酮等抗高温单体,同时引入分子量调节剂和交联剂改善分子结构,合成黏度效应低、分子结构立体、高温稳定性强的钻井液用低分子增稠剂。该增稠剂在复合盐水基浆(150℃)和饱和盐水基浆(200℃)中均具有良好的降滤失能力,在高密度钻井液体系中可有效改善钻井液的高温稳定性,密度2.3 g/cm^(3)复合盐钻井液经200℃、7 d高温静置后,静态沉降因子为0.512,具有良好的沉降稳定性。

In order to maintain good rheology and improve settlement stability under high temperature conditions,author synthesized low-molecular-weight thickener for drilling fluid with low viscosity effect,three-dimensional molecular structure and strong temperature resistance.It was synthesized by using acrylamide(AM)and acrylic acid(AA)as raw materials,introducing high temperature resistant monomers such as AMPS and NVP,introducing molecular weight regulators and crosslinking agents to improve the molecular structure.The low-molecular-weight thickener for drilling fluid had good capability of filtration reduction in both compound brine-based slurry(150℃)and saturated brine-based slurry(200℃).In high-density drilling fluid systems,it could effectively improve the high temperature stability of drilling fluid.The stability coefficient(SF)of 2.3g/cm^(3) compound salt drilling fluidis was only 0.512,after standing under 200℃for 7 d.