Abstract
The flexibility of gasification, which incorporates both characteristics of the kind of biomass and options for producing heat or fuel, is what stimulates interest in biomass gasification research and application possibilities. One of the challenges with gasification is the accurate prediction of gasification products from the wide array of feedstocks and operational conditions, making the design and optimisation challenging. There are several studies on equilibrium models that have been published, but most of the models examined the impact of moisture and heating value. Examining the other parameter effects within the same model can enhance the accuracy of a gasification model. This work aims to create stoichiometric equilibrium models that enable the analysis of parameter effects on a specific feedstock's gasification products for use in optimisation and system modelling. A mathematical model for fixed bed gasifiers that use downdraft gasification for wood as a feedstock is presented. When the algebraic model equations are solved, the conversion behaviour of wood biomass throughout a gasification process is predicted in terms of the composition of the end products. The model has been verified with published experimental data from the literature demonstrating good agreement. The created model may be regarded as a helpful tool to simulate the impact of numerous different biomass feedstocks and operating conditions on gas characteristics and the simple algebraic formulation allows for the application of the model for optimisation purposes.