NO_x Reduction as a Co-benefit of SO_2 Adsorption by Trona in a Coal-fired Rotary Kiln Calciner

摘要

Trona is known to be an effective sorbent of SO_x resulting from coal combustion. The effectiveness of this adsorption process can vary with gas temperature and major species concentrations, but favorable conditions can typically be identified and targeted for many coal combustion applications. Past work in this area has been focused on power applications and chemical mechanisms and rates for describing these reactions have been proposed and evaluated. The extension of these concepts to describe related impacts on NO_x chemistry has also been performed and quantitatively evaluated. Reaction Engineering International and OCI Wyoming have recently undertaken an effort to leverage this information and implement descriptions of these heterogeneous chemical reactions into a CFD-based approach. This approach was then validated using emissions data from OCI Wyoming's Green River plant. Results of this evaluation indicate that trona resulted in a 12-14% reduction in NO_x emissions for the conditions existing in a trona calcining kiln.