This report describes research on coal combustion processes and pyrite oxidation processes. Work focuses on the oxidation of iron pyrite to form the non-slagging magnetite.

This paper presents results of investigations on the transformation of iron pyrite to non-slagging species during staged combustion of pulverized coal. Work focuses on the oxidation of iron pyrite to magnetite.

This document is the third quarterly status report on a project conducted at the High Temperature Gasdynamics Laboratory at Stanford University, Stanford, California and concerned with enhancing the transformation of iron pyrite to non-slagging species during staged, low-NO(subscript x) pulverized coal (P.C.) combustion. The research project is intended to advance PETC's efforts to improve our technical understanding of the high-temperature chemical and physical processes involved in the utilization of coal. The work focuses on the mechanistic description and rate quantification of the effects of fuel properties and combustion environment on the oxidation of iron pyrite to form the non-slagging species magnetite. The knowledge gained from this work is intended to be incorporated into numerical codes that can be used to formulate anti-slagging strategies involving minimal disturbance of coal combustor performance.

This document is the eighth quarterly status report on a project that is conducted at the High Temperature Gasdynamics Laboratory at Stanford University, Stanford, California and is concerned with enhancing the transformation of iron pyrite to non-slagging species during staged, low-NO(subscript x) pulverized coal (P.C.) combustion. In general, the project has the following objectives: (1) the characterization of the various mechanisms of intraparticle mass transfer and chemical reaction that control overall pyrite combustion rates and (2) the synthesis of the reaction rate resistances of the various mechanisms into a general rate expression for pyrite combustion. The knowledge gained from this project will be incorporated into numerical codes and utilized to formulate slagging abatement strategies involving the minor adjustment of firing conditions. Ultimately, the benefit of this research program is intended to be an increase in the range of coals compatible with staged, low-NO{sub X} combustor retrofits.