改性腐植酸油基降滤失剂的两步法合成与性能评价

Two-step synthesis and performance evaluation of humic acid fluid loss additive for oil-based drilling fluid

以腐植酸为原料,采用酰氯化-酰胺化两步法在40℃下反应4h合成改性腐植酸油基降滤失剂,并通过红外光谱对改性腐植酸进行了表征。在最佳加量下,其中温中压滤失量低于2mL、高温高压滤失量低于8mL。该降滤失剂抗160℃高温,在20%(w)CaCl_2或10%(w)NaCl盐污染条件下,能保持较低的滤失量。

Using humic acid as raw material, the modified humic acid oil based on fluid loss agent was synthesized under 40 ℃ for 4 h by two step of acyl chlorination and amidation, and the structure of modified humic acid was characterized by infrared spectroscopy. The indoor test shows that the modified humic acid in oil base drilling fluid has good fluid loss effect. When the dosage is 3%, filtration loss is 2.0 mL at medium temperature and medium pressure, fluid loss is 8.0 mL at high temperature and high pressure. The fluid loss agent could resist the high temperature of 160 ℃, and remain low amount of fluid loss under the condition of 20 % CaCl2 or 10% NaCl salt