在低电流、低电压条件下,采用电化学氧化法处理水中低浓度氨氮.分别考察了电流密度、极板间距、pH、氯离子浓度对氨氮降解的影响.通过运行成本的分析,确定最佳工艺条件.在此条件下,考察SO42-和初始氨氮浓度对电化学氧化处理低浓度氨氮的影响.结果表明,在电流密度为2 m A·cm-2、极板间距为5 mm、pH为10、Cl-浓度为1 200 mg/L的条件下对初始浓度为100 mg/L的氨氮废水进行电解,电解8 h后,氨氮可以从100 mg/L降至0,其平均能耗为0.032 k W·h/g(NH4+-N),出水时的pH为5.53呈弱酸性;且SO42-对电解去除氨氮的影响很大,初始氨氮浓度对处理氨氮的影响很小.
Removing low-concentration ammonia nitrogen from wastewater by electrochemical oxidation with low current and voltage was studied.The effects of current density,plate spacing,pH,chloride ion concentration on ammonia removal were discussed,and the optimal condition were selected by analyzing the operation costs. SO42-concentration and initial concentration of ammonia nitrogen were investigated under the optimal condition. The results showed that the initial ammonia nitrogen concentration had little effect on removal of ammonia nitrogen and the SO42-had a great influence on the removal of ammonia nitrogen,the ammonia nitrogen could be decreased from 100mg/L to 0 when the current density was 2 m A·cm-2,the plate spacing was 5 mm,pH was 10 and the chlorine ion concentration was 1 200 mg/L after 8 h. The power consumption was 0.032 k W·h/g(NH4+-N),and the pH of the effluent was 5.53.