溶解氧对电极生物膜反硝化性能的影响

Influences of dissolved oxygen on denitrification abilities of biofilm-electrode system

摘要:

为确定溶解氧对电极生物膜反硝化性能的影响,设计并运行了一套"电解-电极生物膜反应器"(ER&BER),研究电化学反应器(ER)的电解电流强度对电极生物膜反应器(BER)进水溶解氧(DO)质量浓度及反应器内DO质量浓度梯度的影响.结果表明,电化学反应和微生物的呼吸共同影响BER中DO的消耗.分别单独改变和连续改变ER系统内的电解电流,测定BER系统内阴极区溶解氧质量浓度以及硝酸盐氮和亚硝酸盐氮的去除情况.研究发现,BER系统阴极区溶解氧均低于2 mg/L,进水中溶解氧质量浓度提高使阴极区溶解氧也略有提高,这对硝酸盐氮的去除没有明显影响,而使亚硝酸盐积累略有增加.通过透射电镜观察DO对生物膜上微生物生物相的影响,初步发现DO质量浓度的变化会引起生物相的一些变化.

Abstract:

To study the influences of dissolved oxygen(DO) on denitrification ability of biofilm-electrode,a system consisting of electrolysis reactor and biofilm-electrode reactor was fabricated.The effects of electrolysis current of electrolysis reactor system on the DO content in influents and the DO grads in biofilm-electrode reactor were investigated.Results implied that both microbe respiration and electrochemistry had effects on DO consumption in biofilm-electrode reactor system.The DO,the removal of nitrate-N and the nitrite-N in the biofilm-electrode system were measured when the current in the electrolysis reactor was applied in continuous and batch changes.Although the DO in cathodes area had a little increasing with the increasing of DO in influent,the DO values were all below 2 mg/L.No evidence proves the influences of DO on nitrate removal but the negative influences might be obtained on nitrite accumulation.Some changes on microbial species of bio-film electrode were found at different DO concentrations by transmission electron microscopy micrographs.