利用盘式曝氧技术提高注入污水含氧量试验

Experiment on Improving Oxygen Content of Injected Sewage by Using Disk Aeration Technology

目前大庆油田主要采用射流曝氧工艺提高污水中含氧量,但是在杏南矿区应用过程中发现,污水中含氧量以及Fe^(2+)、S^(2-)等二价离子去除率未能达到预期。针对射流曝氧污水溶氧量不足的问题,应用注水罐盘式曝氧技术,对已建注水曝氧站进行改造,探索一种新型盘式曝氧方式,并在A和B两座配注站开展了盘式曝氧技术现场试验。盘式工艺采用供气增氧微氧化装置,利用离心鼓风机或罗茨鼓风机为水体进行曝氧,解决射流曝氧工艺曝氧后污水溶氧量不足的问题,保证聚驱稀释用水溶氧值满足开发效果。研究结果表明:在相同气水比的情况下,鼓风机设备造价及能耗均低于空压机;在相同气量情况下,曝气器氧传递效率高,对水中溶氧量提升幅度大。经现场试验,使用供气增压设备后,出水溶氧量由1.5 mg/L提高到6.6 mg/L,配制聚合物黏度平均提高7.6%以上,聚合物溶液稳定性大幅提升,保证了聚驱稀释用水溶氧值满足开发要求。

Currently,the jet aeration technology is mainly used in Daqing Oilfield to increase the oxygen content in sewage.However,during the application process in the Xingnan mining area,it was found that the oxygen content in sewage,and the removal rate of bivalent ions such as Fe^(2+)and S^(2-)failed to meet expectations.In response to the problem of insufficient dissolved oxygen content in the jet-aerated sewage,a new type of disk aeration method is explored by using water injection tank disk aeration technology to transform the existing water injection aeration station,and conducted on-site tests of the disk aeration technology at two injection distribution stations A and B.The"disk type"process uses a gas supply and oxygen increasing micro oxidation device,using a centrifugal blower or a Roots blower to aerate the water body,solving the problem of insufficient dissolved oxygen content in sewage after aeration in the jet aeration process,and ensuring that the dissolved oxygen value of polymer flooding dilution water meets the development effect.The research results show that:under the same gas-water ratio,the cost and energy consumption of the blower equipment are lower than those of the air compressor.Under the same air volume,the aerator has high oxygen transfer efficiency,and dissolved oxygen in the water is considerably improved.After field testing,using the gas supply booster equipment,the dissolved oxygen in the effluent increased from 1.5 mg/L to 6.6 mg/L,and the viscosity of the prepared polymer increased by an average of more than 7.6%.The stability of the polymer solution is significantly improved,ensuring that the dissolved oxygen value of the polymer flooding dilution water meets the development requirements.