Modelling sugarcane vinasse processing in an acidogenic reactor to produce hydrogen with an ADM1-based model

Abstract

Biohydrogen can be produced by dark fermentation of sugarcane vinasse, wastewater from the sugar-alcohol industry, in acidogenic anaerobic bioreactors. In this work, a model based on ADM1 was constructed to model anaerobic processing of sugarcane vinasse in an acidogenic batch reactor. Based on experimental data, hypotheses were put forward. Two new pathways were assumed: Acetate+Lactate→Butyrate+Hydrogen and Glycerol→Butyrate+Hydrogen. A sensitivity analysis was carried out to reduce the number of free parameters, after which the model was calibrated with the experimental data. The proposed model was able to adequately describe sugar and glycerol consumption, acetate and lactate production and consumption and hydrogen and butyrate production over the operational time at an initial concentration of vinasse of 30kgCODm−3. Nevertheless more improvements can be carried out to make the model more realistic and to cover intermediate metabolic pathways under conditions of lower vinasse concentration, such as 15kgCODm−3 and 20kgCODm−3.