Author/Authors :
Tong، نويسنده , , Shuang and Chen، نويسنده , , Nan and Wang، نويسنده , , Heng and Liu، نويسنده , , Hengyuan and Tao، نويسنده , , Chen and Feng، نويسنده , , Chuanping and Zhang، نويسنده , , Baogang and Hao، نويسنده , , Chunbo and Pu، نويسنده , , Jiaoyang and Zhao، نويسنده , , Jiamin، نويسنده ,
Abstract :
In this study, central composite design (CCD) and response surface methodology (RSM) were applied to optimize the C/N and current density in a heterotrophic/biofilm-electrode autotrophic denitrification reactor (HAD-BER). Results showed that nitrate could be effectively reduced over a wide range of C/Ns (0.84–1.3535) and current densities (96.8–370.0 mA/m2); however, an optimum C/N of 1.13 and optimum current density of 239.6 mA/m2 were obtained by RSM. Moreover, the HAD-BER performance under the optimum conditions resulted in almost 100% nitrate-N removal efficiency and low nitrite-N and ammonia-N accumulation. Furthermore, under the optimum conditions, H2 generated from water electrolysis matched the CO2 produced by heterotrophic denitrification by stoichiometric calculation. Therefore, CCD and RSM could be used to acquire optimum operational conditions and improve the nitrate removal efficiency and energy consumption in the HAD-BER.
Keywords :
Nitrate reduction , HAD-BER , Central composite design (CCD) , optimization , response surface methodology (RSM)
