Experiment and CFD simulation of hybrid SNCR–SCR using urea solution in a pilot-scale reactor

• Published in: Computers & chemical engineering 2010-10, Vol.34 (10), p.1580-1589
• Main Authors: Nguyen, Thanh D.B., Lim, Young-Il, Eom, Won-Hyeon, Kim, Seong-Joon, Yoo, Kyung-Seun
• Format: Article
• Language: English
• Subjects: Computational fluid dynamics; Computational fluid dynamics (CFD); Computer simulation; Droplets; Honeycomb; Hybrid SNCR–SCR; Mathematical models; NO x reduction; Nonuniform; Pilot-scale flow reactor; Reactors; Reduction; Selective catalytic reduction (SCR); Selective non-catalytic reduction (SNCR); Titanium dioxide
• ISSN: 0098-1354; 1873-4375
• DOI: 10.1016/j.compchemeng.2009.12.012

The urea-based selective non-catalytic reduction (SNCR) experiment and modeling previously presented by Nguyen, Lim, et al. (2008) was extended in this study to the hybrid SNCR–SCR process for nitrogen oxides (NO x ) removal in a pilot-scale flow reactor. The 5 wt% urea–water solution was sprayed into the SNCR zone and a commercial V 2O 5–WO 3/TiO 2 catalyst in the form of monolith honeycomb was applied in the SCR zone. The NO x reduction efficiency of 91% was obtained from hybrid SNCR–SCR experiments, while 81% of NO x was reduced from the SNCR zone at 940 °C and a normalized stoichiometric ratio (NSR) of 2.0. The turbulent reacting flow computational fluid dynamics (CFD) model with a nonuniform droplet size distribution was used, incorporating with the reduced seven-step reactions of SNCR and one Arrhenius-type SCR kinetics. The CFD simulation results showed a reasonable agreement with the experimental data in the temperature range between 900 and 980 °C.