Thermal analysis in numerical thermodynamic modeling of solid fuel conversion

Abstract

Detailed kinetic models dominate in combus- tion modeling. However, their application is often com- plicated by insufficient knowledge of a mechanism and reaction rates for heterophase interactions especially as applied to gasification. The novel approach using thermo- dynamic 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 prob- lem statement and accessible information on the process. Thermal analysis has been deployed to infer proper con- straints for modeling of wooden biomass gasification. The advantage of the method consists in much higher avail- ability of the initial information compared with detailed kinetics. Model results are in good agreement with experiment.