稻田水动力微生物燃料电池性能及其脱氮效果研究

The Performance of Hydrodynamic Microbial Fuel Cells and Its Denitrification Effect in Paddy Field

【目的】探究微生物燃料电池在利用稻田分泌物的条件下对稻田氮素的去除作用。【方法】将圆桶形微生物燃料电池装置置于模拟的稻田排水环境中,水流带来的水稻根际分泌物是微生物的能量来源。本研究设置三种不同氮质量浓度的进水水平C1(8.57 mg/L)、C2(42.58 mg/L)、C3(77.13 mg/L),定期对出流液体进行取样,通过流动分析仪测定出流液中铵态氮、硝态氮量。【结果】C3处理中输出电压和运行期间做的总功最高,总发电量16.6 mW·h;当环境温度低于35℃时,输出电压值随温度增加而增加。对C3处理的输出电压与温度、前一日温度变化、运行时间进行多元回归分析,相关系数0.86,环境温度及其变化与装置的输出电压显著相关;铵态氮处理结束时的出流液中的铵态氮质量浓度比处理开始时的下降13%,硝态氮质量浓度下降23%。【结论】水动力微生物燃料电池装置在模拟的稻田排水环境运行过程中起到脱氮作用,且脱氮效果随装置的运行增强。

Microorganism decompose organis under anaerobic condition produce electrons.Microbial fuel cell is a device use these electrons produces electric energy.Microbial fuel cells are used to treat wastewater domestic sewage and industrial wastewater.【Objective】This paper aims at study the appliation of Microbial fuel cells in agricultral outputs treatment.【Method】Cylindric hydrodynamic microbial fuel cell devices was put in the simulative paddy field drainage ditch to explore its actual operation and denitrification,whose only carbon source was root exudates carried by water flow.Root exudates contains various sugars.The simulated inflow is treated with nitrogen concentration,and devided into three levels of C1(8.57 mg/L),C2(42.85 mg/L)and C3(77.13 mg/L).The outflow was taken as sample regularly.The ammonium nitrogen and nitric nitrogen content in the water samples are analyzed by flowing analyzer.【Result】C3 had the highest total generating capacity which was 16.6 mW·h.The changes of ambient temperature and ambient temperature had significant influence on the operation parameters of the device.The output voltage would increase with the environmental temprature when environment tempreture was under 35 degree Celsius.The output voltage will drop sharply when the environment temperature was 40℃,and it would rise back when the temperature is dropping to the appropriate range.The output voltage of C3 was analyzed by multiple regression analysis with temperature,temperature change and operating days,and the correlation coefficient reached 0.86.Ammonium nitrogen concentration of outflows in later stage decreased 13%than early stage of experimental treatment.Nitric nitrogen concentration of outflows in later stage decreased23%.【Conclusion】The hydrodynamic microbial fuel cell device can be operated in the simulated water drainage environment of the paddy field,and it plays the role of denitrification during operation.The content of nitrogen in the outflows is decreased with the operation of the device.