电絮凝+微气泡臭氧氧化耦合工艺深度处理压裂废水

Advanced treatment of fracturing wastewater by electroflocculation hybrid with micro-bubble ozone oxidation process

采用电絮凝+微气泡臭氧氧化耦合工艺处理页岩气压裂废水,考察了不同工艺、初始pH、电流密度、臭氧投加量、反应时间等因素对压裂废水COD去除效果的影响。结果表明,电絮凝+微气泡臭氧氧化耦合工艺对页岩气压裂废水具有较好的处理效果,在初始pH为9.5、电流密度为15 mA/cm^(2)、臭氧投加量为80 mg/L和反应时间为60 min最优反应条件下,压裂废水COD去除率可达到85.96%。电絮凝与微气泡臭氧氧化之间存在协同作用,碱性环境更有助于页岩气压裂废水的电絮凝耦合微气泡臭氧氧化处理,过高的电流密度将出现显著的浓差极化现象和导致絮凝体与悬浮颗粒失稳脱附,适当增加臭氧投加量将有利于加快电絮凝+微气泡臭氧氧化耦合体系中·OH的生成速率和产生量,提高废水处理效果。

A hybrid process of electroflocculation and micro-bubble ozone oxidation was applied for the treatment of shale gas fracturing wastewater,and the influences of the different treatment processes,the initial pH,current density,ozone dosage,reaction time on the COD removal of fracturing wastewater treatment were investigated.The results showed that the hybrid process of electroflocculation and micro-bubble ozone oxidation had a good effect on the treatment of shale gas fracturing wastewater.The removal rate of COD had reached 85.96%under the initial pH 9.5,current density 15 mA/cm^(2),ozone dosage 80 mg/L,reaction time 60 min.There was a synergistic effect between electroflocculation and micro-bubble ozone oxidation.The alkaline environment was more conducive to the electroflocculation coupled micro-bubble ozone oxidation treatment of shale gas fracturing wastewater.A significant concentration polarization would lead to unstable desorption of flocs and suspended particles when the current density was excessive.An appropriate increase in ozone dosage would accelerate the formation rate and quantity of·OH,and improve the wastewater treatment effect.