储存尿液电化学法脱氮的影响因素

Influence factors of electrochemical removal of nitrogen from stored urine

生活污水中约80%的氨氮来自尿液,收集尿液并脱氮处理可极大减轻生活污水处理负荷.本实验用Ti/Ru O2-Ti O2电极作为阳极,不锈钢板作为阴极,在有机玻璃电解槽中研究考察电流密度（20~100 m A/cm^2）、储存尿液初始p H（9~12）以及Na Cl投加量（4~16 g/L）对储存尿液（250 m L）的脱氮效果.结果表明,最佳脱氮工艺参数为：电流密度80 m A/cm^2,初始p H在11左右,Na Cl投加量为8 g/L,电解时间达到270 min.在此最优化条件下,氨氮和总氮的去除率分别是91.83%和88.34%;处理1 L尿液消耗0.311 k W·h电能.可见,该方法具有快速、低能耗、高效优点,在源分离尿液氮处理方面具有应用前景.

About 80% of ammonia in municipal wastewater comes from urine. In the present study,Ti/Ru O2-Ti O2 anode and stainless steel cathode were used in the nitrogen removal process of stored urine. The operating variables in the electrochemical nitrogen removal including the current density（ 20-100 m A/cm^2）,initial p H（ 9-12）,and sodium chloride dosage（ 4-16 g /L） were considered to be the influence factors on the nitrogen removal. The the most effective electrochemical process was observed when utilizing a current density at about 80 m A/cm^2,initial p H at about 11,and sodium chloride dosage at about 8 g/L. Under the optimum conditions the removal rates of ammonia and total nitrogen were 91. 83% and 88. 34%,erspectively,and the reaction time was 270 min. A total of 0. 311 k W·h energy was consumed for treating 1 L of stored urine. This process was rapid and efficient with low cost,and it would have promising applications in removal of nitrogen in stored urine.