Alexandria Engineering Journal (Oct 2020)
Experimental and numerical study of sawdust air-gasification
Abstract
This work presents a numerical and experimental investigation of sawdust gasification in a fluidized bed using air. The fluidized bed reactor was tested in the Faculty of Engineering, Mansoura University, Egypt. In the experimental part, the experiments were made in a fluidized bed gasifier to optimize the gasifying of sawdust pellets using air. The syngas composed mainly of CO, H2, CH4, and CO2 as in the typical gasification process. The obtained experimental results showed that the syngas contents are strongly affected by the equivalence ratio and temperature. Increasing of ER improves char burning to produce more CO2, but H2 gradually increased till ER = 0.35 instead of CH4, CO and H2 increased as temperature increased. The temperature of 900 °C and an equivalence ratio of 0.35 is the right combination of sawdust gasification as operating conditions. A kinetic-hydrodynamic one-dimensional model was developed and validated with experimental results. This model is used to expect the effect of various operating parameters on a biomass gasification performance, such as temperature, equivalence ratio, and different hydrodynamic parameters. This model capable of expects the axial gas composition along the gasifier, as well as the syngas composition and heating value of produced gas and the gasification efficiency at the reactor outlet. The model results were in reasonable agreement with experimental results and published results.
