Production of H2 and Methanol via Dark Fermentation: A Process Optimization Study

This work presents a process optimization study for the production of H-2 and methanol via dark fermentation. A kinetic model is developed for dark fermentation, and it is implemented in the process optimization by means of orthogonal collocation. As a result from the entire process optimization, the optimal operating conditions of the process are determined. The investment in the process is estimated to be $18.2 M and has a production cost of $37.6 per kg of H-2 produced when 1 kg/s of biomass is treated. The second process optimization study is developed for the production of methanol via hydrogenation of CO2. This process is estimated to require an investment of $ 16.4 M, and the production cost is $6.9/kg of methanol when 1 kg/s of biomass is treated. In both cases, the amounts of H-2, 8 g/s, and methanol produced, 38 g/s, are very low in comparison with the resource treated.