Small Scale Entrained-Flow Gasification of Biocoals Made by Hydrothermal Carbonization

Abstract

Recently biomass upgrading technologies like torrefaction and hydrothermal carbonization are investigated to make low quality biomasses and residues available for energetic use. Hydrothermal carbonization offers the conversion of wet, heterogeneous biomass to a homogenous biocoal with enhanced grinding and dewatering properties. In this work the utilization of biocoal in an entrained-flow gasifier is analyzed for subsequent heat and power generation in a gas engine. Basic simulation results of an air-blown gasification process in Aspen Plus^® are presented and the development of a small scale autothermal entrained-flow gasifier is described. Large scale technologies like pneumatic dense-phase conveying were applied successfully in small scale with biocoals. Operational experiences and key findings are discussed. First trials were carried out using lignite as comparable fuel.