旋流萃取分离技术处理石化电脱盐废水

采用旋流萃取分离技术处理某炼油厂常减压装置电脱盐废水(初始废水含油量约为5 000 mg/L),优化了废水除油的工艺条件。试验结果表明,废水除油的最佳工艺条件为:旋流萃取分离机中心转子的转速960 r/min、废水流量2 000 L/h、废水温度80℃。废水经旋流萃取分离后,废水的含油量小于200 mg/L,废水除油效果较好;分离后油相的含水量约为0.1%(w),盐质量浓度小于20 mg/L,可回注到常减压装置原料罐循环利用。对于2 Mt/a的常减压装置,采用旋流萃取分离技术后,每年可减少支出100.4万元。

Treatment of Petrochemical Electro-Desalination Wastewater by Swirl Extraction

The electro-desalination wastewater （with 5 000 mg/L of initial oil content） from the crude oil unit of a refinery was treated by swirl extraction technology. The optimum process conditions for oil removal are as follows：rotating speed 960 r/min,wastewater flow 2 000 L/h,wastewater temperature 80 ℃. After swirl extraction,the oil content of the wastewater is less than 200 mg/L. The separated oil with 0.1% （w） of water content and below 20 mg/L of salt mass concentration can be recycled to the head tank. The cost for wastewater treatment will be reduced by 1.004×10⁶ yuan per year for a 2 Mt/a crude oil unit.