Thermal analysis in numerical thermodynamic modeling of solid fuel conversion

Abstract

Detailed kinetic models dominate in combustion modeling. However, their application is often complicated by insufficient knowledge of a mechanism and reaction rates for heterophase interactions especially as applied to gasification. The novel approach using thermodynamic model of extreme intermediate states (MEIS) could make up an efficient alternative. MEIS is strictly deterministic and simple in structure. Along with the search for the final equilibrium, it allows partial equilibria to be found and various macroscopic phenomena to be taken into account, e.g., transport phenomena and kinetic rates. The core problem in MEIS construction is formulation of macrokinetic constrains whose form depends on the problem statement and accessible information on the process. Thermal analysis has been deployed to infer proper constraints for modeling of wooden biomass gasification. The advantage of the method consists in much higher availability of the initial information compared with detailed kinetics. Model results are in good agreement with experiment.