低温无固相钻井液配方优选及经济性评价

Optimization of a Low-temperature and Non-solid Drilling Fluid Formulation and the Economic Evaluation

摘要:

为解决高原冻土和天然气水合物勘探过程中钻进和取心问题，选择了NaCl作为抗冻剂，抗盐共聚物GTQ和水解聚丙烯酰胺PHP作为主要聚合物试剂，采用正交试验法，在常温下优选出了9组配方，经过低温测试，确定了在 -15 ℃可用的钻井液配方Z1（20%NaCl+0.1%PHP+1.2%GTQ+1%KHm）和Z2（25%NaCl+0.15%PHP+1.0%GTQ+1%KHm），其主要性能指标分别为：AV值46.5、47.5 mPa·s，PV值34、35 mPa·s，YP值12.8、12.8 Pa，FLAPI值6.8、7.6 mL/30 min。经成本核算，2种配方具有比较好的经济性，可以满足高原冻土层钻进要求。

Abstract:

NaCl was selected as antifreeze to solve difficulties for drilling and coring in plateau permafrost and exploration process of gas hydrate, and salt tolerant copolymer GTQ and hydrolyzed polyacrylamide PHP were taken as main polymer reagent. With orthogonal test method, 9 groups of optimal formulas were obtained in normal temperature, after low temperature test, the drilling fluid formulation Z1（20%NaCl 0.1%PHP 1.2%GTQ 1%KHm）and Z2 （25%NaCl 0.15%PHP 1.0%GTQ 1%KHm）were determined, which could be used in the temperature of -15℃. The main performance indicators were: AV values were 46.5 and 47.5 MPa·s, PV values were 34 and 35MPa·s, YP values were both 12.8Pa and FLAPI were 6.8 and 7.6mL/30min. By the cost accounting, the 2 formulas are economic and can meet the requirements of plateau permafrost drilling.