Pilot scale study for control of industrial boiler nitrogen oxide emissions using hydrogen peroxide treatment coupled with wet scrubbing-system design.

摘要

The research in this study was of the scale-up effects on a new control technology for nitrogen oxide (NO_x) emissions. The new technology was designed for use on stationary combustion sources where the flue gas stream is greater than 900°F. The study was conducted on the flue gases from an industrial boiler. The new technology incorporates liquid injection of hydrogen peroxide (H₂O₂) into the hot gas stream followed by caustic wet scrubbing. The parameters addressed in this study were NO _x (100–800 ppm), H₂O₂ (50–3600 ppm), sulfur dioxide (100–900 ppm), and temperature (830°F–1030°F). The concentration of the H₂O₂ used in this study was 50%. Nitric oxide (NO) conversions of 90–97% for H₂O ₂:NO molar ratios of 1:1 were achieved. The effects of sulfur dioxide on conversion efficiency were found to be synergistic for H₂O ₂:NO molar ratios of less than 1:1 and insignificant for molar ratios of 1:1 or greater. Follow-on studies are underway to investigate rate constants for the reactions involved in this process, scrubber design parameters, and modifications to this technology for low temperature flue gas streams, and to further investigate the nitrogen speciation observed in the process.