title: Combustion Modifications of Batch Annealing Furnaces and Ammonia Combustion Ovens for NOX Abatement in Steel Plants.
abstract: NOX control employing several combustion modification techniques is studied in batch annealing furnaces and ammonia combustion ovens in steel plants. The fuels of the annealing furnace and ammonia oven are by-product fuel gases and ammonia vapor, respectively, which are generated in the same steelworks. Study of the emission characteristics of the annealing furnace show that delayed combustion can effectively reduce NOX emissions. Delayed combustion is accomplished by air-staging in burners, off-symmetric mixing of fuel and air, and air-biasing in the furnace, and these modification can operations achieve 60%, 40%, and 26% of NOX reductions, respectively. For the ammonia oven, NOX emission from combustion of ammonia vapor is remarkably reduced by staging the air injected into the oven, adjusting the total air rate, and adding by-product fuel gases to the combustion system.
authors.affiliation: a Department of Chemical Engineering , Chung Yuan Christian University , Chung-Li , Taiwan , USA.
authors.forename: Hsisheng
authors.initials: H
authors.lastname: Teng