Use of simulation to optimize NOx abatement by absorption and selective catalytic reduction

This paper describes the development of an ASPEN PLUS simulation model for a commercial NOx abatement system involving both absorption and selective c atalytic reduction (SCR). The model helps identify operator guidelines and retrofit options needed to enable the commercial system to operate efficien tly during surges in NOx-laden fumes without incurring costly fines. The re sulting model applies a reactive-distillation module with a practical react ion set for NOx absorption and implements a kinetic model for SCR. The simu lation results agree well with both design specifications and literature da ta and provide practical insights for optimum operation and economical retr ofits of the commercial system.