Equilibrium Composition of Simulated Coal Combustion Products: Relationship to Fireside Corrosion and Ash Fouling

Abstract

A computer solution of chemical equilibrium composition is presented for high-temperature combustion reactions related to fireside corrosion and ash fouling. A simple calculation system, which models the injection of a sodium-potassium mixture through a flame, is solved for equilibrium compositions at temperatures from 1500 deg to 3000 deg F at varying oxygen levels from 0.1 percent to 17 percent in the gas stream and 1 atmosphere pressure. At equilibrium, principally alkali sulfates and hydroxides are produced in the model of a combustion product atmosphere resembling that in a coal-fired boiler. A total of 42 reactions involving 40 chemical species were treated in the reactant mixture and compositions for the entire system are included.