Hydrogen production from sugar beet molasses – a techno-economic study

Two-stage fermentative hydrogen production process comprising dark fermentation and photofermentation followed by gas upgrading is studied from the technical and economic points of view. It is assumed that a conceptual hydrogen plant is connected to a sugar factory so that technical sucrose solutions produced there (raw juice, thick juice and molasses) can be used as fermentation feedstocks. Process data needed for the study are based on the results of a recently completed research project and in the techno-economic assessment of hydrogen production, data acquired in the sugar industry are taken into account. A parametric study of the cost of hydrogen production from molasses shows that the total cost is highly sensitive to the capital and operating costs of the photofermentation stage. Prospects of cost reduction through further development of the two-stage fermentative process are discussed.