Sorption-enhanced gasification - Analysis of process parameters impact on the system's operation with a dual fluidised bed model

Abstract

Sorption-enhanced gasification (SEG) is a promising technology for synthetic biofuel production from biomass. A semi-empirical 1-dimensional dual fluidised bed (DFB) model for the SEG process with coupled bubbling fluidised bed and circulating fluidised bed is developed. The model is used to analyse the operation of a pilot-scale adiabatic DFB system. A study of the gasifier operation temperature's influence on the system's mass and energy balances in the range of 650 °C–775 °C was conducted. In addition, an effect of the gasifier's steam-to-carbon (S/C) ratio on the system's mass and energy balances and producer gas composition in the range of 700 °C–775 °C was investigated for the production of synthetic biofuels. The model gave a good prediction for producer composition against experimental studies. The results show the effect of gasifier temperature and S/C ratio on the mass and energy balances of the system. The variation of the main parameters showed processes suitability for the production of dimethyl ether, methanol and synthetic natural gas. The simulations improved the understanding of the SEG processes physical operation. The knowledge of the system's operation is valuable in reactor system design and the development of the system's efficient operation ways for synthetic biofuel production.