Experimental Study On High Water-cut Crude Oil For Water Pre-separation And Wastewater Treatment

With the oilfield development entered into the high water cut period and extreme high water cut period,oil extraction became water extraction,which led to the constructions in the ground handling system was difficult to adapt to water-based process needs.Therefore,it has a very important significance that separating some water from crude oil production and purifying the oily sewage in the well site,booster pumping station or transfer station.Based on the previous study of SPEPRI,the key technology of water pre-separation and wastewater treatment of high water-cut crude oil was studied,and the short process technology of the integrated water pre-separation and wastewater treatment was studied.What's more,this paper also carried out field experiment research in Jiangsu oilfield.The results show that the main process of integrated pre-separation and wastewater treatment short process can be used to purify the high water-cut crude oil in one hour,the outlet content of oil and suspended particle can be controlled under 50mg/L respectively and that,after using the filter process for treatment,the outlet quality will meet reinjection criteria.The key to the rapid separation of the integrated equipment is to integrate high-flow swirling technology and multi-phase rapid separation technology with coalescence,flotation and so on.Field application tests show that the optimum working condition of the integrated equipment are inlet flow rate 13~25 m~3/h,the split rate 50%~70%,the dosage 80mg/L and the working pressure is more than 0.17MPa when the average inlet water-cut is 80%,In addition,the integrated equipment is capable of operating in a large flow range and at a lower operating pressure.