羟甲基化木质素磺酸盐添加剂对钻井液性能的影响

为了进一步优化木质素磺酸盐作为钻井液处理剂的效能,利用其与甲醛的羟甲基化反应制备了羟甲基化木质素磺酸盐;采用红外光谱仪、X射线粉末衍射仪、扫描电镜等分析了其结构;测定了改性前后的木质素磺酸盐对钻井液流变性、降滤失性、黏土水化膨胀抑制性等性能的影响.结果显示,改性后的羟甲基化木质素磺酸盐的整体结构变化不大,但羟基数量增加,与水的相溶性增强.与木质素磺酸盐相比,羟甲基化木质素磺酸盐在室温下对基浆有较强的提黏作用,经180℃高温老化后降黏、降滤失作用有所增强,形成的泥饼厚度降低,对黏土水化膨胀的抑制作用增强.

Effect of hydroxymethylated lignin sulfonate additive on the performance of drilling fluid

Hydroxymethylated lignin sulfonate was prepared viathe hydroxymethylation reaction of lignin sulfonate with formaldehyde so as to enhance the performance as a drilling fluid additive.The product was characterized by Fourier transform infrared spectrometry,X-ray diffraction,and scanning electron microscopy.Moreover,the effect of as-prepared hydroxymethylated lignin sulfonate additive on the performaces of drilling fluid,including rheology behavior,filtration loss reducing ability,and inhibition against clay hydrous disintegration was investigated.Results show that hydroxymethylation of lignin sulfonate leads to little change in its framework but causes increase of the hydroxyl group amount and the intermiscibility with water.As compared with lignin sulfonate,the hydroxymethylated lignin sulfonate can more effectively increase the viscosity of the base fluid at room temperature and reduce the viscosity and filtration loss after aging under 180 ℃.Besides,the hydroxymethylated lignin sulfonate generates thinner mud-cakes and exhibits better inhibition against clay hydrous disintegration than lignin sulfonate.