Nitrogen Oxides Removal Characteristics of SNCR-SCR Hybrid System

The SNCR-SCR (selective non-catalytic reduction-selective catalytic reduction) hybrid system is an economical NOx removal system. In this study, the effect of the operating parameters of the SNCR-SCR hybrid system on NOx removal efficiency was investigated. When the SNCR reactor was operated at a temperature lower than the optimum temperature (900~950 ), an additional NO removal is obtained basesd on the utilization of slip. On the other hand, the SNCR reactor operated above the temperature resulted in no additional NO removal of SCR due to decomposition of . Therefore, the SNCR process should be operated at optimum temperature to obtain high NO removal efficiency and low slip. Thus, it is important to adjust NSR (normalized stoichiometric ratio) so that can be maintained at an appropriate level.