Abstract: CQ-BOL biological oil lubricant is developed from waste cooking oil for drilling fluid. The biological oil lubricant can solve the technological problems of high torque and high friction existing in drilling of horizontal wells in Changqing area, which affect drilling safety and improvement of drilling rate. Indoor evaluation indicates that the reduction rate of lubricant coefficient is higher than 82.3 percent and the heat tolerance is up to 150°C. The biological oil lubricant is low in toxicity and free from fluorescence with a good compatibility with the existing drilling fluid system. It is used for more than 150 wells after it was successfully tested in horizontal wells in Changqing. Based on the onsite application, the friction coefficient of mud cake is controlled within the range of 0.0262-0.0524 and the extreme lubricant coefficient is less than 0.10 when the dosage of the biological oil lubricator is between 0.5 percent and 3 percent, providing drilling fluid with a good lubricating and friction-reducing function.

Key words: waste cooking oil, drilling fluid, lubricity, horizontal well, Changqing Oilfield

摘要： 为解决长庆地区水平井钻井过程中因钻具与井壁的扭矩大、摩阻高影响安全钻井及钻井提速的技术瓶颈,尝试了将来源广、经济实惠的废弃食用油研制成钻井液用生物油润滑剂CQ-BOL的实验研究。室内评价结果表明,该生物油润滑剂的润滑系数降低率高达82.3%,抗温达150℃,低毒性、无荧光,与目前使用的钻井液体系配伍性良好。生物油润滑剂在长庆油气水平井试验成功后规模化推广应用150余口井,现场维护加量范围为0.5%~3%,泥饼滑块摩阻系数维持在0.0262~0.0524,极压润滑系数低于0.10,始终保持钻井液具有良好的润滑减阻性能,应用效果优良。

关键词: 废弃食用油, 钻井液, 润滑性, 水平井, 长庆油田