环保型水基钻井液在胜利油田的研究与应用

Study and Application of Environmentally Friendly Water Base Drilling Fluid in Shengli Oilfield

废弃钻井液一直是钻井工程的主要污染物之一,而研发环保型水基钻井液体系,从源头上控制废弃钻井液环境污染,已成为现阶段实现"绿色钻井、清洁生产"的重要途径。针对胜利油田环保型水基钻井液技术需求,自主研发了基于改性淀粉的抗高温环保降滤失剂HBFR,其在淡水、盐水中均具有良好的降滤失性能,抗温达150℃,形成了环保型水基钻井液系列配套处理剂,构建了综合性能良好的抗高温(150℃)环保型水基钻井液体系(SLHB)。评价结果表明,SLHB体系具有良好的流变、滤失、抑制页岩水化及抗污染性能,高温高压滤失量为10.2 mL,EC50值大于1×10^5 mg/L,BOD5/CODCr为16.2%,可达到国家污水排放二级标准。SLHB已在胜利油田现场应用10余口井,较好地满足了胜利油田环保钻井液技术需求。

Waste drilling fluid is one of the major pollutants of the drilling operations. In the development of environmentally friendly water base drilling fluids, controlling the production of waste drilling fluid from the source is becoming an important means of achieving "green drilling and clean production". An environmentally friendly high temperature filter loss reducer, HBFR, has been developed from modified starch to satisfy the needs of environmentally friendly water base drilling fluids in Shengli Oilfield. HBFR has good filtration control property in both fresh water and saltwater drilling fluids, and is resistant to high temperature(150 ℃). As one of the additives used for formulating environmentally friendly water base drilling fluids, HBFR has been used to formulate a high temperature environmentally friendly drilling fluid SLHB. SLHB in laboratory experiment showed good rheological properties, filtration control capacity, shale inhibitive capacity and contamination resistance, and can be used at 150 ℃. The HTHP filter loss of SLHB was 10.2 mL. SLHB has satisfied the level 2 requirement for sewage discharge because it has EC50 of greater than 1×10^5 mg/L and BOD5/CODCr of 16.2%. SLHB has been used on more than 10 wells in Shengli Oilfield, satisfying the needs for environment protection and providing a technical support for the "green development" in Shengli Oilfield with environmentally friendly drilling fluids.