Hydrogen production within a polygeneration concept based on dual fluidized bed biomass steam gasification

Dual fluidized bed biomass steam gasification generates a high calorific, practically nitrogen-free product gas with a volumetric H-2 content of about 40%. Therefore, this could be a promising route for a poly-generation concept aiming at the production of valuable gases (for example H-2), electricity, and heat. In this paper, a lab-scale process chain, based on state of the art unit operations, which processed a tar-rich product gas from a commercial dual fluidized bed biomass steam gasification plant, is investigated regarding H-2 production within a polygeneration concept. The lab-scale process chain employed a water gas shift step, two gas scrubbing steps, and a pressure swing adsorption step. During the investigations, a volumetric H-2 concentration of 99.9% with a specific H-2 production of 30 g kg(-1) biomass was reached. In addition, a valuable off-gas stream with a lower heating value of 7.9 MJ m(-3) was produced. Moreover, a techno-economic assessment shows the economic feasibility of such a polygeneration concept, if certain feed in tariffs for renewable electricity and H-2 exist. Consequently, these results show, that the dual fluidized bed biomass steam gasification technology is a promising route for a polygeneration concept, which aims at the production of H-2, electricity, and district heat. (c) 2016 Elsevier Ltd. All rights reserved.