Technological challenges for producing hydrogen from biomass

This paper evaluates the production of hydrogen through gasification and dark fermentation, comparing the results in terms of energy consumption, Hydrogen productivity and quality as well as  potential environment impacts. The feedstock selected was Pinus Patula Shiede residues. The raw material was characterized by measuring moisture content (AOAC 928.09 method), klason lignin content (TAPPI 222 om-83 method), acid-soluble lignin content (TAPPI 250UM-85 method) holocellulose content (ASTM Standard D1104 method), cellulose content (TAPPI 203 os-74 method) and ash content (TAPPI Standard T211 om-93 method).The energy analysis was carried out using simulation tools for both processes. The simulation tool was the commercial package Aspen Plus v8.0 (from Aspen Technology, Inc., USA). Besides, eight environmental categories were evaluated using the waste reduction algorithm developed by the Environmental Protection Agency (EPA).  In order to feedback the simulation step, verification experiments were developed at small scale using bioreactors and a gasifier “GEK Gasifier (10 KW/h) Power Pallet”. The gas produced for the two ways were analyzed (CO, H2, CO2, CH4) using an analyzer (GASBOARD-3100P, Portable syngas infrared analyzer).

It was demonstrated that the best option today to produce hydrogen is the thermochemical way. However the challenges for the dark fermentation were properly addressed.