基于响应面法优化废弃油基钻井液的萃取方法

针对油气田钻井过程中经多次循环导致基液老化变质而无法使用的废弃油基钻井液,采用响应面法优化废弃油基钻井液萃取实验。以石油醚(60~90 ℃)作为萃取剂,通过单因素实验确定了编码参数,考察了液料比(萃取剂与废弃油基钻井液加量质量比,g/g)、萃取温度、萃取时间3因素5水平的中心组合设计,建立数学模型并进行验证。结果表明,对于液料比1.5:1,萃取时间25 min,萃取温度36.5 ℃的最佳萃取条件,萃取率的预测值为82.97%,实测值为82.18%,相对误差仅有0.95%。

Extraction method of waste oil based drilling fluid by response surface methodology

Oil-based drilling fluids are abandoned owing to deterioration after being circulated many times during the process of oil and gas drilling. However, it could be extracted to recycle the oil using extraction treatments optimized by response surface methodology (RSM). The extraction solvent was petroleum ether (60 to 90 ℃). Code parameters were determined by single-factor tests. The liquid-waste ratio, extraction time, and extraction temperature, which were selected as influencing factors with a combination design with three factors and five levels, were optimized by RSM in order to enhance extraction efficiency. Results showed that the measured value was 82.18% and the predicted value was 82.97% using optimized extraction conditions of liquid-waste ratio of 1.5:1, extraction time of 25 min, and extraction temperature of 36.5 ℃. The relative error was 0.95%.