微生物燃料电池强化铁碳微电解去除低浓度硝态氮技术

本研究成功构建一种耦合反应器，借助微生物燃料电池（MFC）来强化铁碳微电解还原硝酸盐能力，同时达到提高低浓度硝态氮去除效率和延长铁碳床使用寿命的目的。该耦合反应器运行原理在于利用阳极室内污泥发酵产电特性，为阴极室还原硝酸盐提供电子，强化铁碳床能力，减缓铁腐蚀过程。实验结果表明：在铁碳比为1:1、进水初始pH为7的条件下，该耦合反应器在实验初期对低浓度硝态氮（10 mg·L-1）的去除率为90.33%，而纯铁碳床反应器的硝态氮去除率仅有77.97%，耦合反应器的去除效率高于纯铁碳床12.36%，证明通过耦合MFC能够强化铁碳微电解还原硝态氮的能力。随着铁腐蚀程度的增加，运行20周期后耦合反应器对于硝态氮的去除效率仍高于纯铁碳床28.77%，证明耦合反应器能够延长铁碳床使用时间，并且当铁碳比较低时对硝酸盐去除的强化效果更好。

Enhance Iron-Carbon Micro-electrolysis for the Removal of Low Concentration Nitrate Nitrogen by Microbial Fuel Cell

In this study, a coupling reactor was successfully set up to enhance the ability of iron-carbon micro-electrolysis for reducing nitrate by microbial fuel cells (MFC). It also achieved the goals of improving removal efficiency of low-concentration nitrate nitrogen and prolong the service life of iron-carbon beds in the meantime. The operation principle of the coupling reactor was utilizing the electricity generation characteristics of sludge fermentation in the anode chamber to provide electrons for nitrate reduction in the cathode chamber, improve iron-carbon bed capacity and slow down the iron corrosion process. The experimental results showed that in the initial condition of 1:1 iron-carbon ratio and pH=7, the removal rate of low concentration nitrate nitrogen (10 mg·L-1) in the coupling reactor was 90.33% at the initial stage of the experiment. While the removal rate of nitrate nitrogen in the pure iron-carbon bed reactor was only 77.97%. The nitrate removal efficiency in coupling reactor was 12.36% higher than pure iron-carbon bed. The results proved that the ability of iron-carbon micro-electrolysis for reducing nitrate nitrogen can be enhanced by coupling MFC. Along with the increasing iron corrosion degree, the removal efficiency of nitrate nitrogen in coupling reactor was still 28.77% higher than that in the pure iron-carbon bed after 20 cycles operation, which proved that the coupled reactor can prolong the work time of iron-carbon bed. In addition, the enhancement effect for nitrate removal was better when the ratio of iron-carbon was comparatively low.