非常规油气田开发含油岩屑环保无害化处理技术

Environmentally Friendly and Harmless Treatment Technology for Oily Rock Cuttings in Unconventional Oil and Gas Field Development

非常规油气田的勘探开发通常使用大量的油基钻井液,在钻井过程中不可避免地产生较多的含油岩屑,给周边生态环境带来了较大的污染威胁。为了提高此类含油岩屑的处理效率,达到含油岩屑环保无害化处理的目的,采用超声波辅助化学清洗法对含油岩屑进行了清洗处理,并优化了处理工艺参数。结果表明:液固质量比越大、清洗剂质量分数越高、实验温度越高,经过超声-化学清洗处理后的岩屑含油率相对就越低;而随着清洗时间的延长以及超声功率的增大,处理后的岩屑含油率则呈现出“先降低后升高”的趋势。当实验液固质量比为4∶1、清洗剂质量分数为8%、清洗温度为40℃、清洗时间为30 min、超声功率为300 W时,对目标含油岩屑的清洗处理效果最好,处理后的岩屑含油率可以降低至0.22%,能够达到国家标准GB 18599—2020中的排放要求。研究结果可为非常规油气田开发含油岩屑的高效处理提供一种参考。

The exploration and development of unconventional oil and gas fields usually use a large amount of oil-based drilling fluid,which inevitably generates a large amount of oily rock cuttings during the drilling process,posing a significant pollution threat to the surrounding ecological environment.In order to improve the treatment efficiency of such oily rock cuttings and achieve the goal of environmentally friendly and harmless treatment of oily rock cuttings,ultrasonic assisted chemical cleaning method was used to clean the oily rock cuttings,and the treatment process parameters were optimized.The results showed that the higher the liquid-solid mass ratio,the higher the mass fraction of cleaning agent,and the higher the experimental temperature,the lower the oil content of rock cuttings after ultrasonic chemical cleaning treatment;as the cleaning time prolonged and the ultrasonic power increased,the oil content of the treated rock cuttings showed a trend of"first decreasing and then increasing".When the experimental liquid to solid-mass ratio was 4∶1,the cleaning agent mass fraction was 8%,the cleaning temperature was 40℃,the cleaning time was 30 min,and the ultrasonic power was 300 W,the cleaning effect on the target oily rock cuttings was the best.The oil content of the treated rock cuttings was reduced to 0.22%,meeting the emission requirements of the national standard GB 18599—2020.The research results can provide some reference for the efficient treatment of oil-bearing cuttings in unconventional oil and gas field development.