Technological barriers of biomass gasification

This work deals with the main technological barriers which limit the commercial diffusion of biomass gasifiers. Five technological barriers have been identified. 1) The properties of biomass are variable so gasifiers require flexibility to process different kinds of feed. 2) The high moisture content of biomass limits the energetic efficiency of the process. 3) Problems arising from solid handling and management. 4) Biomass ash can form particulates and alkaline vapours. 5) The presence of tar in the gas can lead to fouling and plugging of the plant pipelines. Each barrier is discussed with concern on different gasifier configuration and end-use of the gas. In addition, since the tar abatement is a specific problem related to biomass gasification, a preliminary experimental study of tar thermal cracking is described. The tar and gas yields as well as the gas composition are reported as functions of temperature. The experimental results are then used to estimate kinetic parameters for the thermal cracking of gasification tars