Theoretical study of the influence of mixing in the SNCR process. Comparison with pilot scale data

A theoretical study of the influence of mixing on the selective non-catalyt ic reduction (SNCR) process has been performed. The study includes the use of a detailed kinetic reaction mechanism together with a simple approach fo r mixing based on the "maximum mixedness model" proposed by Zwietering (195 9). Two different configurations for that simple mixing approach have been considered and discussed, i.e. the "direct approach" which implies entrainm ent of the jet flow (containing the SNCR reduction agent) into a bulk flow (containing the products of the main combustion zone); and the "reverse app roach" which represents entrainment of the bulk flow into the jet stream. T he main features of both approaches applied to the SNCR process are analyze d and discussed. Furthermore, comparison of the results obtained with the p resent approaches with different experimental pilot scale results is perfor med. (C) 2000 Elsevier Science Ltd. All rights reserved.