Analysis of fluidized bed gasification of biomass assisted by solar-heated particles

Although biomass gasification using concentrated solar energy is an attractive technology for the production of storable renewable energy and CO2 reduction, several challenges have stalled its deployment over the last decades: high temperature and/or large reactor volume required for complete fuel (char) conversion, the achievement of a steady syngas generation independent of solar radiation variation, and accomplishing effective heat supply at high temperature in large-scale reactors. An alternative approach overcoming these technical challenges is analyzed in this paper. It is based on conducting the gasification of biomass with steam in a fluidized bed using solid particles that are separately heated in a solid particle receiver using concentrating solar energy. The present study includes the thermodynamic and kinetic analysis of solar steam gasification in a completely allothermal single fluidized bed gasifier as well as in a partially allothermal dual fluidized bed gasification system. A theoretical analysis of the reactor performance and its integration with the solar receiver is examined and the state of the art of the most important aspects for developing the proposed technology is reviewed.