Selection of the most suitable pretreatment method by PROMETHEE for baker's yeast production wastewater in Microbial Fuel Cell

BACKGROUND: The high organic load and low biodegradability of the effluent from baker's yeast production limit its use as a substrate in microbial fuel cell (MFC) systems. In this study, baker's yeast production wastewater was used as a substrate in the anode chamber to assess the impact of various pretreatment methods [dilution, microwave (MW), acidic-thermal, basic-thermal and ultrasound (US)] on electricity generation and waste treatment. Additionally, azo dye was used as an electron acceptor at the cathode. Power density and coulomb efficiency were evaluated for electricity generation, and chemical oxygen demand (COD) removal and azo dye removal parameters were evaluated for treatability. RESULTS: The maximum power densities obtained were 83.53, 46.54, 19.41, 67.40, 41 and 33 mW m(-2) for MW, acidic thermal, alkaline-thermal and US pretreatments, diluted raw and raw wastewater, respectively. To determine the most suitable pretreatment method, PROMETHEE was performed using the criteria of maximum power density, COD removal, azo dye removal, coulombic efficiency and pretreatment cost. The most suitable method was found to be MW pretreatment. The order of the alternatives was found to be MW > US > acidic/thermal > diluted raw > raw > alkaline/thermal. With the MW pretreatment, 81.34% azo dye removal, 5 g L-1 COD removal, 0.27% coulombic efficiency and (sic)0.284 L-1 pretreatment cost were obtained. CONCLUSION: The most suitable pretreatment method to be applied to wastewater for the treatment of baker's yeast production wastewater and high energy production was determined as MW using the PROMETHEE approach. (c) 2023 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).