Optimal performance prediction of isothermal feedstock gasifier using unified thermodynamic model

Abstract

In this work, a unified thermodynamic model for isothermal feedstock gasification is proposed to predict the gasification performance at carbon boundary point (CBP), by considering total hydrogen/total carbon, total oxygen/total carbon (entering into the system) and gasification temperature as unifying variables. The unified model is applicable for any combination of feedstocks, any blend of gasification agents O2, steam and CO2 and any practically relevant gasification temperature. The simple model can be solved analytically to predict the amount of unknown gasification agent required to reach CBP. The unified model is also used to predict syngas composition, cold gas efficiency and amount of heat to be supplied, at CBP. The model is validated for different feedstocks, blend of gasification agents and gasification temperatures. The results predicted by the model are within 10% of the results from Aspen Plus.