微生物脱盐电池(MDC)是一种集污水净化、产电和脱盐为一体的新型水处理工艺。构建并运行了10L级堆叠式树脂填充型微生物脱盐中试装置,考察了盐室初始浓度及阳极进水基质浓度对MDC运行效果的影响。初始盐室浓度升高时,平均电流较高,平均脱盐速率提高,但脱盐率降低;阳极基质降解速率基本符合米氏方程,当基质COD〉75mg/L时,近似于零级反应,COD降解速率为71.5mg/(L·h);在阳极水力停留时间为6h且连续流运行模式下,当阳极进水COD在150~600mg/L变化时,阳极出水COD浓度随进水COD浓度增加而增加,但阴极出水COD浓度均低于城市污水排放一级A标准限值,平均电流随进水COD浓度上升,脱盐率为64.1%~82.1%。这为进一步放大MDC反应器并研究脱盐速率提供了参考。
Microbial desalination cell (MDC) is a kind of novel water treatment process by in- tegrating wastewater purification, electricity generation and water desalination. A 10 L pilot-scale stacked MDC packed with ion-exchange resin was built and operated to investigate the influence of the initial salt concentration and substrate concentration of anode influent on MDC performance. The average current and desalination rate of MDC were increased with the increase of initial salt concentration in the desalina- tion chamber, while the desalination efficiency was decreased. Substrate degradation in anode chamber o- beyed Michaelis equation, and could be described in zero-order reaction with constant COD degradation rate of 71.5 mg/(L ~ h) when the substrate COD concentration was higher than 75 mg/L. When the MDC was operated continuously with HRT of 6 h in anode chamber, and the COD concentration of anode influent was ranged from 150 mg/L to 600 mg/L, the anode effluent COD was increased with the increase of influent COD while the COD concentrations of the cathode effluent were all less than the limit of the first grade A of municipal wastewater discharge standard. The average current was increased with the increase of influent COD, and the desalination efficiency was 64.1% to 82.1%. Results provided a reference for further study on scale-up and desalination rate of MDC.