This item is available under a Creative Commons License for non-commercial use only
2.3 MECHANICAL ENGINEERING, Thermodynamics, Chemical engineering (plants, products), Energy and fuels
The efficient utilisation of biomass resources is of utmost importance. Biomass gasification offers much higher efficiencies than combustion. Gasification is a process in which a fuel is converted to a combustible gas (syngas). A dual fluidised bed gasifier known as the fast internally circulating fluidised bed (FICFB) was selected. It has been demonstrated at industrial scale and data is readily available for model validation. An Aspen Plus model was developed to simulate the FICFB gasifier. The model is based on Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it. The model has been validated and predicts syngas composition, heating value and cold gas efficiency (CGE) in very good agreement with published data. Important operating parameters such as gasification temperature (Tg), biomass moisture, steam to biomass ratio (STBR), air-fuel ratio and air and steam temperature were varied. Tg and STBR were found to have very strong influence on syngas composition and heating value. Biomass moisture had the most significant impact on CGE. The other parameters, although less important, were found to have substantial effect on CGE.
W. Doherty, A. Reynolds, D. Kennedy. Aspen plus simulation of biomass gasification in a steam blown dual fluidised bed. Book Chapter: Materials and processes for energy: communicating current research and technological developments, A. Méndez-Vilas (Ed.), Formatex Research Centre, 2013.