三维电极法去除废水中氨氮的研究

发布时间：2018-06-06 02:37

本文选题：氨氮 + 直接电化学氧化　；参考：《西北农林科技大学学报(自然科学版)》2016年11期

【摘要】：【目的】分析三维电极法去除氨氮的主要途径及其氧化机理。【方法】以石墨棒为阳极、不锈钢直筒为阴极、柱状活性炭为粒子电极,自制三维电极反应装置对废水中的氨氮进行处理,考察电解时间、电解电压、电解质(氯离子)浓度和pH值对氨氮去除效果的影响,并对氨氮的去除机理进行分析。【结果】在一定范围内,三维电极对氨氮的去除效果会随着电解电压、电解时间、电解质浓度的增大而上升;当电解电压为9V,电解时间50min,以0.02mol/L的NaCl作电解质,在废水pH呈中性时,三维电极反应装置对废水中氨氮的去除效果最好,去除率最高可达70%。通过试验数据及理论分析可知,氨氮的去除途径主要有2种:一是游离氨(NH3)在电极上直接氧化转化成N2;二是当体系中存在一定浓度的氯离子时,铵离子(NH+4)发生间接氧化反应生成N2。极少量亚硝氮和硝氮的生成表明体系内有少量的氨氮通过·OH、O3等中间氧化活性物质间接氧化。【结论】三维电极法在适宜条件下对废水中的氨氮有着良好的去除效果,并具有反应时间短和二次污染小等特点。
[Abstract]:[objective] to analyze the main ways of removing ammonia nitrogen by three dimensional electrode and its oxidation mechanism. [methods] Graphite rod as anode, stainless steel tube as cathode, columnar activated carbon as particle electrode, The effect of electrolysis time, electrolytic voltage, electrolyte (chloride ion) concentration and pH value on ammonia nitrogen removal was investigated. The removal mechanism of ammonia nitrogen was analyzed. [results] in a certain range, the removal effect of ammonia nitrogen would increase with the increase of electrolytic voltage, electrolytic time and electrolyte concentration. When the electrolysis voltage is 9V, the electrolysis time is 50min and the NaCl of 0.02mol/L is used as the electrolyte, when the pH of the wastewater is neutral, the removal efficiency of ammonia nitrogen in the wastewater by the three-dimensional electrode reaction device is the best, and the highest removal rate is up to 70%. According to the experimental data and theoretical analysis, there are two main ways to remove ammonia nitrogen: one is that free ammonia NH _ 3 is oxidized directly to N _ 2 on the electrode, the other is when there is a certain concentration of chloride ions in the system, Ammonium ion NH _ 4) was oxidized indirectly to form N _ 2. The formation of a very small amount of nitrite nitrogen and nitrate nitrogen indicates that a small amount of ammonia nitrogen in the system is indirectly oxidized by intermediate oxidizing active substances such as OHO _ 3. [conclusion] Three-dimensional electrode method has a good removal effect on ammonia nitrogen in wastewater under suitable conditions. It also has the characteristics of short reaction time and small secondary pollution.
【作者单位】：西安建筑科技大学环境与市政工程学院;陕西省环境科学研究院;
【基金】：陕西省科技统筹创新工程计划项目(2011KTZB03-03)
【分类号】：X703

【相似文献】