A theoretical and experimental study of biomass gasification

The modeling of large-scale gasifiers requires fundamental understanding of gasification of single char particles. In this work, the gasification rate of a singe char particle in an CO2-CO-N2 is investigated by means of (i) construction of a simple numerical model, (ii) material investigation of char and (iii) gasification experiments in a grid reactor. The numerical model indicates the existence of a reaction controlled limit and a diffusion controlled limit. The limiting cases can be discerned experimentally by increasing the partial pressure of nitrogen in the mixture, while keeping the other partial pressures constant. Material investigation of char particles indicates that they can be considered to be non-porous. Preliminary grid reactor experiments indicate that it is possible to test the results of the model experimentally and to verify whether the char is nonporous.