The spray conditions such as spray zone, nozzle type and the concentration of reductant solution were optimized in full-scale urea-based SNCR process for NOx removal from a limestone calcining process. NOx removal efficiency varied with the spray zon...
The spray conditions such as spray zone, nozzle type and the concentration of reductant solution were optimized in full-scale urea-based SNCR process for NOx removal from a limestone calcining process. NOx removal efficiency varied with the spray zone of urea solution even at the same amount of urea, which was closely related to the velocity field of flue gas. The full cone type nozzle revealed higher NOx removal efficiency than the flat spray nozzle. The lower concentration of urea solution was favorable for NOx removal. The varieties of NOx removal efficiency with the employed nozzle type and the concentration of urea solution were mainly due to the degree of mixing between the sprayed urea mists and flue gas. The momentum depending on the size and velocity of the sprayed mists significantly affected the mixing intensity and consequently NOx removal efficiency.