Kinetics of Biohydrogen Production by Dark Fermentation Processes

Various kinetic models were developed to describe the fermentative biohydrogen production in a batch system. These models took into account the effects of substrate degradation (and inhibition), temperature and pH on biomass growth as well as on the rate of biohydrogen production. This chapter summarizes various such models describing the effect of different parameters on the biological hydrogen production process. It was found that the modified Gompertz model was most suitable to describe the progress of biohydrogen formation process. Substrate inhibition was well described by the Andrew model, which is the modified form of the classical Monod model as well as by the Han- Levenspiel model. The modified Logistic model was used to describe the growth of the biomass as well as the rate of biohydrogen production. The effect of temperature was well described by the Arrhenius model, but up to the critical temperature only. The Ratkowsky model was able to describe the effect of both temperature as well as pH on fermentative biohydrogen production.

Keywords: Biohydrogen, dark fermentation, Gompertz model, Andrew model, Han-Levenspiel model, Ratkowsky model, Monod model, inhibition, Luedeking-Piret model, activation energy, Enterobacter cloacae.