An experimental approach aiming the production of a gas mixture composed of hydrogen and methane from biomass as natural gas substitute in industrial applications

Abstract

This work presents an experimental approach aiming the production of a gas mixture composed of H₂ and CH₄, which should serve as natural gas substitute in industrial applications. Therefore, a lab-scale process chain employing a water gas shift unit, scrubbing units, and a pressure swing adsorption unit was operated with tar-rich product gas extracted from a commercial dual fluidized bed biomass steam gasification plant. A gas mixture with a volumetric fraction of about 80% H₂ and 19% CH₄ and with minor fractions of CO and CO₂ was produced by employing carbon molecular sieve as adsorbent. Moreover, the produced gas mixture had a lower heating value of about 15.5MJ·m^-3 and a lower Wobbe index of about 43.4MJ·m^-3, which is similar to the typical Wobbe index of natural gas.

Keywords: Biomass steam gasification; Carbon molecular sieve; Dual fluidized bed; H(2)CH(4); Hythane.