氧化-混凝法用于油田回注污水处理研究

报道了过氧化辅助混凝法处理油田回注污水的研究结果。简述了方法原理。在室内实验研究中将油田污水先用石灰乳处理，使pH值升至7．07～7．3，先后加入合20％H2O2的氧化剂和混凝剂聚硅酸铝铁，沉降后的上清液经砂滤器过滤即得到净化污水。加入氧化剂5mg/L和混凝剂60mg／L，使污水中含油、悬浮固体、总铁、舍硫(S^2-)分别由146、43、26、8．0mg／L降至2．8、2．1、0．1、0mg/L；与单独使用混凝剂相比，混凝剂的最优加量范围由80～100mg／L扩大至40～90mg／L，适应处理水量变化的能力大大增强；氧化剂最优加量范围为4～6mg/L.在中原油田采油三厂进行的现场试验中，过氧化辅助混凝法(5mg／L氧化剂 60mg／L混凝剂)处理后的污水，舍油、悬浮固体、总铁、舍硫、MF、TGB、SRB、腐蚀速率等指标均大大优于混凝法(90mg/L混凝剂)处理后的污水，特别是MFF值高达42，TGB和SRB茵数为0，腐蚀速率为0．0386mm／a；在水处理流程中，被处理水的腐蚀速率除混合罐内高于来水外，均低于0．076mm/a；处理后污水合氧量低，水质的稳定性提高。图5表4参5。

A Study on Treating Recycled Produced Water by Peroxidization Enhanced Coagulation

A new technology of treating produced water for reservoir flooding by peroxidization enhanced coagulation is presented. The principles of the technology are stated briefly. In laboratory experimental investigations the produced water is pretreated by lime slurry to pH 7.03-7.30 and treated by 20% H 2O 2 compounded solution and coagulant AlFe polysilicate, after sedimentation the top water is sand filtered to give purified injection water with following results. H 2O 2 solution of dosage 5 mg/L and coagulant of 60 mg/L added decrease contents of oil, suspended solids, total Fe and sulfide from 146, 43,26 and 8.0 mg/L to 2.8, 2.1,0.1 and 0 mg/L, respectively, and, comparing with simple coagulation method, the range of optimal coagulant dosage enlarges from 80-100 to 40-90 mg/L thus enhancing the ability of the treatment to adapt to varying in water volume being treated; the range of optimal H 2O 2 solution dosage is of 4-6 mg/L. In a plant trial in the 3rd Zhongyuan production factory the quality of the produced water treated by peroxide+coagulant (5+60 mg/L) is significanlty improved in contents of oil, suspended solids, total Fe and sulfide, TGB and SRB population, corrosion rate and MF value, of these MF value is as high as 42, population of TGB and SRB is of zero, corrosion rate is reduced to 0.038 6 mm/a (0.124 8 mm/a for untreated water); the corrosion rate of being treated water along the treating course is low besides that in the mixer and the dissolved oxigen content in treated water is low, too, which indicate increased stability of the water quality in following technologic steps.