Biomass steam gasification - an extensive parametric modeling study

A model for steam gasification of biomass was developed by applying thermod ynamic equilibrium calculations. With this model, the simulation of a decen tralized combined heat and power station based on a dual fluidized-bed stea m gasifier was carried out. Fuel composition (ultimate analysis and moistur e content) and the operating parameters, temperature and amount of gasifica tion agent, were varied over a wide range. Their influences on amount, comp osition, and heating value of product gas and process efficiencies were eva luated. It was shown that the accuracy of an equilibrium model for the gas composition is sufficient for thermodynamic considerations. Net electric ef ficiency of about 20% can be expected with a rather simple process. Sensiti vity analysis showed that gasification temperature and fuel oxygen content were the most significant parameters determining the chemical efficiency of the gasification. (C) 2001 Elsevier Science Ltd. All rights reserved.