电化学氧化法处理氨氮废水的影响因素

为了考查电化学氧化对低浓度废水中氨氮的处理效果,研究阴极材料、阳极材料、电流密度、氯离子质量浓度、极板间距、沸石的添加和氨氮的初始质量浓度等影响因素对氨氮和总氮降解的影响,同时比较研究二维和三维电极对氨氮的去除效果.结果表明,电化学氧化法是一种适宜于废水脱氮的技术,较佳的工艺条件为：极板间距1 cm、电流密度5 mA/cm2、阳极RuO2-IrO2-SnO2/Ti、阴极钛网、氯离子质量浓度200 mg/L、改性沸石为粒子电极,在该条件下反应20 min后氨氮的去除率可达95%.与二维电极对比,三维电极是在多种物理化学过程协同作用下完成对氨氮的去除,可以达到更高的氨氮降解效果和电流效率.

Influencing factors on ammonia removal by electrochemical oxidation treatment

To investigate the degradation of low-concentration ammonia in wastewater by electrochemical oxidation, the effect of various operating factors on ammonia and total nitrogen removal were studied. The experimental parameters were anode, cathode material, current density, chloride concentration, electrode gap, initial ammonium concentration and three-dimensional particle. Both the performances of two-dimensional and three-dimensional electrode were discussed. The results show that electrochemical oxidation is suitable to degrade ammonia from wastewater, and the optimum operating parameters are 1 cm electrode gap, 5 mA/cm2 current density, 200 mg/L chloride concentration, RuO2-IrO2-SnO2/Ti as anode, titanium mesh as cathode, and modified zeolite as three-dimensional particle. Under the optimal conditions, 95% of ammonia is removed after 20 minutes' electrochemical oxidation. The synergetic effects of several physical-chemical processes achieve ammonia removal in the three-dimensional system. Compared to two-dimensional system, ammonia removal and current efficiency are higher in three-dimensional system.