MODELING LOW-TEMPERATURE GAS REBURNING - NOX REDUCTION POTENTIAL AND EFFECTS OF MIXING

A model for simulating reburning in semi-industrial scale has been dev eloped. It consists of a recently developed reaction mechanism for reb urning with C-1 and C-2 hydrocarbons, in combination with ideal reacto r modeling and a simplified mixing approach. The reaction mechanism as well as the mixing model has been validated separately against experi mental data from laboratory and pilot scale tests. Modeling prediction s have been compared with experimental data from a number of pilot sca le studies of gas reburning with good results. The large differences i n reburn efficiency reported in different low-temperature pilot scale experiments are reconciled in terms of the different operating conditi ons used. The model has been used to assess the potential of the rebur n process at low temperatures, and recommendations for process optimiz ation are provided. Results show that the low-temperature gas reburn p rocess has a significant potential for NO reduction and that both the reburn and burnout regions are important in process optimization.