Simultaneously energy production and dairy wastewater treatment using bioelectrochemical cells： In different environmental and hydrodynamic modes  

作　　者：Masoud Hasany Soheila Yaghmaei Mohammad Mahdi Mardanpour Zahra Ghasemi Naraghi 

机构地区：[1]Department of Chemical and Petroleum Engineering, Shafif University of Technology, Azadi Avenue, P.O. Box 11365-9465, Tehran, Iran

出　　处：《Chinese Journal of Chemical Engineering》2017年第12期1847-1855,共9页中国化学工程学报（英文版）

基　　金：supported by Sharif University of Technology,Vice President for Research Grant G930111

摘　　要：A successful design, previously adapted for treatment of complex wastewaters in a microbial fuel cell （MFC）, was used to fabricate two MFCs, with a few changes for cost reduction and ease of construction. Performance and electrochemical characteristics of MFCs were evaluated in different environmental conditions （in complete darkness and presence of light）, and different flow patterns of batch and continuous in four hydraulic retention times from 8 to 30 h. Changes in chemical oxygen demand, and nitrate and phosphate concentrations were evaluated. In contrast to the microbial fuel cell operated in darkness （D-MFC） with a stable open circuit voltage of 700 mV, presence of light led to growth of other species, and consecutively low and unsteady open circuit voltage. Although the performance of the MFC subjected to light （L-MFC） was quite low and unsteady in dynamic state （internal resistance = 100 Ω, power density = 5.15 W.m-3）. it reached power density of 9.2 W.m-3 which was close to performance of D-MFC （internal resistance = 50 d, power density = 10.3 W.m-3）. Evaluated only for D-MFC, the coulombic efficiency observed in batch mode （30%） was quite higher than the maximum acquired in continuous mode （9.6%） even at the highest hydraulic retention time. In this study, changes in phosphate and different types of nitrogen existing in dairy wastewater were investigated for the first time. At hydraulic retention time of 8 h, the orthophosphate concentration in effluent was 84% higher compared to influent. Total nitrogen and total Kjeldahl nitrogen were reduced 70% and 99% respectively at hydraulic retention time of 30 h, while nitrate and nitrite concentrations increased. The microbial electrolysis cell （MEC）, revamped from D-MEC, showed the maximum gas production of 0.2 m3 H2·m-3·d-1 at 700 mV applied voltage.A successful design, previously adapted for treatment of complex wastewaters in a microbial fuel cell(MFC),was used to fabricate two MFCs, with a few changes for cost reduction and ease of construction. Performance and electrochemical characteristics of MFCs were evaluated in different environmental conditions(in complete darkness and presence of light), and different flow patterns of batch and continuous in four hydraulic retention times from 8 to 30 h. Changes in chemical oxygen demand, and nitrate and phosphate concentrations were evaluated. In contrast to the microbial fuel cell operated in darkness(D-MFC) with a stable open circuit voltage of 700 mV, presence of light led to growth of other species, and consecutively low and unsteady open circuit voltage. Although the performance of the MFC subjected to light(L-MFC) was quite low and unsteady in dynamic state(internal resistance = 100 Ω, power density = 5.15 W·m^(-3)), it reached power density of 9.2 W·m^(-3) which was close to performance of D-MFC(internal resistance = 50 Ω, power density = 10.3 W·m^(-3)).Evaluated only for D-MFC, the coulombic efficiency observed in batch mode(30%) was quite higher than the maximum acquired in continuous mode(9.6%) even at the highest hydraulic retention time. In this study,changes in phosphate and different types of nitrogen existing in dairy wastewater were investigated for the first time. At hydraulic retention time of 8 h, the orthophosphate concentration in effluent was 84% higher compared to influent. Total nitrogen and total Kjeldahl nitrogen were reduced 70% and 99% respectively at hydraulic retention time of 30 h, while nitrate and nitrite concentrations increased. The microbial electrolysis cell(MEC), revamped from D-MFC, showed the maximum gas production of 0.2 m^3 H_2·m^(-3)·d^(-1) at 700 mV applied voltage.

关 键 词：Dairy wastewater Darkness Light Microbial electrolysis cell Microbial fuel cell Nitrogen Phosphate 

分 类 号：X703[环境科学与工程—环境工程]