(143e) Multi-Scale Modelling of Biomass Gasification: The Effects of Intraparticle Transfer on Syngas and Biochar Production

Biomass gasification is an efficient and environmentally friendly technology to realize energy conversion from biomass. In this work, a coupled representative particle and fuel-bed model was developed based on a multi-scale approach. In this model, the reactor was discretized in the flow direction of inlet gasifying agent and a fuel-bed model was constructed to characterize gas-solid field in the gasifier reactor. In each cell, a representative particle model was developed to predict the effects of intraparticle transfer on the flow field and biomass conversion rate. In addition, a three-region approach (i.e. natural, mixed and forced convection region) was applied in this model in terms of different fluid velocity profiles inside the gasifier reactor. The molecular, particle and reactor levels were all considered in the multi-scale modelling approach. The effects of particle shape and size, intraparticle transfer, different gasification agents and air inlet locations on the gasification performance were investigated in this work. Experimental results were used to validate the model and the deviation between the model prediction and experimental data was found to be less than 15%.