电化学脱稳技术处理油田含聚污水

Treatment of polymer-containing oilfield wastewate by electrochemical destabilization technology

采用“电化学除油器—斜板除油器—核桃壳过滤器”模拟装置处理模拟含聚采油污水,考察了有/无清水剂加入条件下含聚污水的处理效果,并对电化学除油机理进行了分析.实验结果表明：各级处理单元的除油率与电化学处理时间成正比,不加入清水剂、电化学处理40 min时,各级处理单元的除油率均超过92％;在电化学除油器前加入清水剂100mg/L、电化学处理20 min时,各级处理单元的除油率分别为98.8％～99.4％,处理后污水含油量小于30 mg/L,处理效果优于在斜板除油器前加入清水剂;电化学处理与清水剂处理有良好的协同除油效果,可大幅降低清水剂用量.机理分析结果表明,电化学作用主要使吸附于油-水界面的产出聚合物降解、脱稳,实现了对油-水界面膜强度和界面电荷的有效破坏,除油效果优异且处理后的絮体松散、无黏附性.

The simulated polymer-containing oilfield wastewater was treated in a set of simulation devices containing electrochemical unit, inclined plate oil skimmer and walnut shell filter. The treatment effects with or without clarifying agent addition were evaluated, and the electrochemical oil-removing mechanism was analyzed. The experiment results show that： The oil removal rates of the treatment units are proportional to the electrochemical treatment time and they are all over 92% when the electrochemical treatment time is 40 min and no clarifying agent is added; When 100 mg/L of clarifying agent is added before the electrochemical unit and the electrochemical treatment time is 20 min, the oil removal rates of each treatment units are 98.8%-99.4%, the oil content of the treated wastewater is below 30 mg/L; The electrochemical treatment and clarifying treatment have a good synergistic effect on oil-removal, which can greatly decrease the clarifying agent dosage. The mechanism analysis results show that, with electrochemical treatment, the residual polymers absorbed to oil-water interface are degraded and destabilized, and the strength of oil-water interfacial film and the oil-water interface charges are decreased. The oil-removal effect of electrochemical treatment is good and the flocs are loose and unadhesive.