铁阳极/生物阴极单室电池脱氮及产电效能

Nitrogen removal and power production efficiency of iron anode/biocathode single-chamber cell

研究了铁阳极生物阴极单室电池无机废水脱氮及产电效能,并探究了生物阴极优势菌群结构.结果表明,在外接1000Ω电阻,进水40mg/L硝氮的条件下单室电池的内阻仅为224.1Ω,并且最大功率密度达到1.82W/m^(3),总氮去除率为40%.降低外电阻和硝氮负荷后,电池在外接200Ω电阻情况下可以稳定运行与处理硝氮负荷为20mg/L的无机废水,在2d内总氮去除率达到95.8%,最大去除负荷为0.0102kgNO_(3)^(-)-N/(m^(3)·d),硝氮去除负荷提升了1倍,说明单室铁阳极生物阴极电池具有良好的去除无机废水中低浓度硝氮的能力.生物阴极群落分析表明,与接种污泥相比,生物阴极群落多样性降低,绝对优势菌属为Thiobacillus,相对丰度为40.8%,为阴极电自养反硝化主要菌属.

The denitrification and electricity generation efficiency of inorganic wastewater from iron anode biocathode single-chamber cells were investigated,and the dominant bacterial community structure of the biocathode was examined.The results showed that the internal resistance of the single-chamber cell was only 224.1Ωunder the condition of external 1000Ωresistor and 40mg/L nitrate-nitrogen feed water,and the maximum power density reached 1.82W/m^(3)with the total nitrogen removal rate of 40%.After lowering the external resistance and nitrate-nitrogen load,the cell could be stably operated and treated inorganic wastewater with a nitrate-nitrogen load of 20mg/L under the external 200Ωresistance,and the total nitrogen removal rate reached 95.8%within 2d.The maximum nitrate-nitrogen removal load was 0.0102kgNO_(3)^(-)-N/(m^(3)·d),which was a one-fold increase in nitrate-nitrogen removal load,indicating that the single-chamber iron-anode biocathode cell has a good capacity to remove low concentrations of nitrate-nitrogen in inorganic wastewaters.Analysis of the biocathode community showed that the diversity of the biocathode community was reduced compared with that of the inoculated sludge,and the absolute dominant genus was Thiobacillus,with a relative abundance of 40.8%,which was the main genus for cathodic electroautotrophic denitrification.