Oily Wastewater Reuse Technology Research Of Northern Shanbei Oilfield

As the onshore oil fields in China have been into mid-late stage of development, the quantity of oil fields produced water increase rapidly because of the rise of water ratio. Oil recovery will be enhanced by re-injecting oil fields produced water effective treated as alternative sources of new water. This will also achieve double benefit of saving and emission reduction.This paper aims to solve the key problems of re-injection treatment of oil fields produced water such as the control of water quality stability, the effective control of corrosion rate, the stability of treated water and compatibility with the formation water, the impact on the formation properties of treated water, the reduction of produced sludge.Through researching oil production wastewater reinjection relating to the YoufangVillage oil region located in Northern Shaanxi, wastewater treatment process was optimized, the water injection requirements from oil field development were met; by evaluating the performance of wastewater treatment chemicals, an efficient, economical and safe complex wastewater disposal agent was proposed; by revising and improving oil field injection wastewater indicators, the adaptability of water reinjection was proposed, and the technical support for efficient, low-cost treatment and reuse of oilfield wastewater was provided.The results show the wastewater treatment process that the use of " untreated watwerâ†'pH rconditioning agentâ†'DT-04â†'PACâ†'DT-01â†'reaction tank (mixing tank)â†'settling tank (flotation tank)â†'twice filter" was feasible, selection and use of DT-04type sterilizating desulfuratingagent,PAC inorganic flocculants, DT-01type organic flocculant is reasonable. the wastewater treatment effects were proved to be good:the unit ran smoothly, pH, oil content, suspended solids can be reached7.0,8.7mg/L,7.0mg/L respectively, and the total iron content is0.48mg/L of the treated water; After low sludge sewage treatment wastewater technology, the corrosion of the reinjection water system can be further reduced, and the controlled corrosion rate was0.0536mm/a, less than the petroleum industry level of0.076mm/a; the cost of the wastewater treatment agent can be controlled at1.55yuan/m3or so.