pH值和碳氮比对微生物燃料电池脱氮除磷效果的影响

【目的】探究pH值和碳氮比对微生物燃料电池脱氮除磷的影响,找出适宜pH值的和碳氮比。【方法】采用单室微生物燃料电池装置,设置不同的阳极液的pH值(W1=5、W2=6、W3=7、W4=8、W5=9);选取pH值=7,设置不同的碳氮比(N1=1∶1、N2=2∶1、N3=4∶1、N4=8∶1、N5=16∶1),共10个处理,测量2个反应周期内输出电压值、COD、氨态氮、硝态氮、总氮和总磷的变化。【结果】在其他条件相同的情况下,只改变阳极液的pH值,输出电压随pH值增大先增大后减小;pH值为8时产电性能最佳,最大电压为204.74 mV;COD、氨态氮、硝态氮、总氮随pH值增大呈先降低后增大的趋势,在pH值为8时,其去除效率最高,分别为74%、38%、93%和58%;在pH值为9时,总磷的去除效率最优为24%。只改变碳氮比时,当碳氮比为4时电压最大,为158.33 mV;COD、氨态氮、硝态氮、总磷的去除率随碳氮比增大先增大后减小,当碳氮比为4时,COD的降解率最大为65%;当碳氮比为2时,氨态氮的降解效率最好为35%;当碳氮比为8时,硝态氮和总磷的去除效率最高,分别为96%和16%;总氮的去除效率随碳氮比的增大而提高,当碳氮比为16时,总氮的去除效率最高,为59%。【结论】碳氮比为4∶1、pH值为8时可以取得较好的脱氮除磷效果。

Effect of pH and C/N on Nitrogen and Phosphorus Removal in Microbial Fuel Cell

【Objective】The purpose of this paper is to study the effect of pH and carbon-nitrogen ratio on removal of nitrogen and phosphorus from soil using microbial fuel cell.【Method】A single-chamber microbial fuel cell was used, in which pH in the anodized liquid varied from 5.0 to 9.0, and when the pH was 70 we examined carbon-nitrogen ratio at 1∶1, 2∶1, 4∶1, 8∶1 and 16∶1 respectively. In each experiment, we measured the change in voltage, COD, ammonia, nitrate, total nitrogen and total phosphorus in two changing cycles of the pH and the carbon-nitrogen ratio.【Result】When else conditions were the same, increasing pH in the anolyte to 8.0 increased the voltage to 204.74 mV, with the associated removal efficiency of COD, ammonia, nitrate and total nitrogen being74%, 38%, 93%, and 58% respectively. But a further increase in the pH deteriorated performance of the cell.When the pH was 9.0, the removal efficiency of total phosphorus peaked at 24%. The voltage peaked at 158.33 mV when carbon-nitrogen ratio was 4. The removal rate of COD, ammonia, nitrate and the total phosphorus increased first followed by a fall as the carbon-nitrogen ratio increased, peaking at 65% when the carbon-nitrogen ratio was 4. When the carbon-nitrogen ratio was 2, the removal rate of ammonia peaked at 35%. The removal efficiency of nitrate and total phosphorus peaked at 96% and 16% respectively when the carbon-carbon ratio was 8.0.The removal efficiency of total nitrogen increased with the increase in carbon-nitrogen ratio, peaked at 59% when the ratio was 16.【Conclusion】Keeping the carbon-nitrogen ratio at 4 and the pH at 8 was most efficient to remove nitrogen and phosphorus from the soil water.