Kinetic Studies on the Sulfidation of Iron by Sulfur Bearing Low-Btu Gases

摘要

The use of a low-Btu gas as a reducing agent for iron oxide was shown to be favorable at temperatures of 800 sup 0 C or greater. Little benefit was seen in terms of increased reduction rates at higher pressures (up to 5 atmospheres) or in varying either the H sub 2 concentration or CO/CO sub 2 ratio, within the range of a low-Btu gas. Sulfidation was found to occur in reaction with iron and not iron oxide. It was found that to avoid contamination of the reduced iron, very low levels of H sub 2 S are necessary in the gas phase (approx. =0.05%). Kinetic data for the sulfidation of reduced iron oxide discs by a sulfur bearing low-Btu gas were taken to clarify the mechanism for the sulfidation reaction. Sulfidation was found to increase with H sub 2 S concentration, system pressure and temperature, and to depend weakly on H sub 2 concentration and CO/CO sub 2 ratio. A model based on combined Multicomponent and Knudsen diffusion through the FeS product layer was developed and used to describe sulfidation. 40 refs., 16 figs. (ERA citation 13:024813)