Analysis of the Fundamental Aspects of Oxidation of Rich Methane Mixtures in Matrix-Type Converters

Abstract

Equilibrium distribution of oxidation products was calculated for the system СН₄ + ψО₂ → products at 0.5 < ψ < 1.0 and temperature of 900–1700 K, with the existence of phase transitions in the system taken into account. Two regions are conditionally distinguished: I, at ψ > 0.6 and temperatures higher than 1000–1200 K (depending on ψ), when there is no Csolid in the system; and II, if this component is present in the system. The range of working temperatures and values of ψ, at which the matrix conversion process occurs, falls within region I. A nearly 100% conversion of oxygen and methane is reached within this region; there is no Csolid; and CO, H₂, CO₂, and H₂O are products of the partial oxidation of methane in equilibrium. The temperature limits within which the system passes into region II and the formation of the synthesis gas is accompanied by the appearance of soot were determined. Formulas describing the dependence of the yield of oxidation products per mole of converted methane at various ratios between the methane and oxygen concentrations were derived. An expression was obtained on the basis of experimental data, which can be used to approximately calculate to within <6% the most important technological parameter of the matrix conversion process, [H₂]/[CO] ratio.