目前大多数油田废水经处理后直接用于回注,其控制指标是含油量和悬浮物,主要利用“二段”和“三段”治理工艺进行净化。随着国内大部分油田进入三次采油期,废水的产生量增多,一部分废水需排放到地表水体中。相应地对外排废水的COD_Cr指标提出了要求,过去的回注用水处理工艺无法满足需要,这就给很多油田的外排废水处理提出了新的研究课题。作者针对油田废水中COD_Cr的去除,介绍了国内研究单位主要采用的生物处理、混凝沉淀、电化学等几个方法的研究情况。

Nowadays most oil-field wastewater is refilled into underground after treated by“two-stage”or “three-stage” technics.The main technical control parameters are the concentration of oil and SS.The amount of wastewater is increasing , because domestic oil-fields have entered the third period of oil extraction, some of which has to be discharged into surface water.Meanwhile, the COD_Cr of discharged wastewater becomes one of the technical control targets, and the past technics which were used to treat refilled water can not meet the demands any more.Therefore a new study task aiming at the discharging wastewater treatment in many oil-fields appears.Domestic research institutions focus on biological treatment,flocculation and agglomeration and electrochemistry and so on to remove COD_Cr from oil-field discharging wastewater.