Optimization of reinjection treatment technology for oilfield wastewater in Longdong area

¹ Longdong University, College of Energy Engineering, Qingyang 745000, China
² Gansu Energy Group Company Limited, Qingyang 745000, China
³ Second Petroleum Production Factory, Changqing Oilfield Company of PetroChina, Qingyang 745000, China
⁴ Longdong University, School of Foreign Languages, Qingyang 745000, China

^* Corresponding author: Xiulan Zhu, keaizhuk@126.com

Abstract

With the long-term water injection development of Longdong oilfields, most of the oilfield blocks have been fully in the mid-high water cut period, and the amount of oil production wastewater is increasing year by year. In order to prevent the waste of resources and energy of oil production sewage, the oil production sewage after reaching the standard is treated for reinjection, which will ensure the sustainable development of the oil field. Oil production wastewater contains crude oil, solid-phase suspended solids and other pollutants, with high salinity, and problems such as difficulty in oil-water separation, sludge, scaling and corrosion. The sewage treatment system uses a multifunctional water treatment device to effectively remove oil and filter through the “special microorganism + air flotation + filtration” process, and build a sludge sewage tank for sludge discharge and backwashing. The reformed oil recovery wastewater reinjection treatment technology turns “sewage” into “clear flow”, reduces operating costs, improves wastewater treatment efficiency, and meets the water quality requirements of oilfield reinjection water.