Modeling of a Two-Bed Reactor for Low-Temperature Removal of Nitrogen Oxides in Nitric Acid Production

In this study, the modeling of low-temperature catalytic abatement NOX and N2O from tail gases in a weak nitric acid plant utilizing single-pressure 0.716 MPa system was performed. A one-reactor concept assumes that first bed, is reduced by ammonia on commercial vanadia–alumina catalyst, second decomposed proprietary nickel–cobalt catalyst. The kinetics decomposition Cs/Ni0.1Co2.9O4 catalyst experimentally studied an isothermal flow reactor. reaction rate constants were determined varying residence time temperature; these data formed basis for heat mass transport adiabatic reactor which mitigation nitrogen oxides occurred. Taking into account given spatial limitations inside allowable temperatures, layer heights evaluated to ensure residual content less than 50 ppm. Catalyst loading using layers estimated tail-gas rates 46,040–58,670 m3/h. Simulations showed optimum inlet temperature 260 °C; case, conversion targets achieved range m3/h while adhering bed height outlet limitations.