Engineering development of coal-fired high performance power systems, Phase 2: Selective non-catalytic reduction system development

Most of the available computational models for Selective Non- Catalytic Reduction (SNCR) systems are capable of identifying injection parameters such as spray droplet size, injection angles and velocity. These results allow identification of the appropriate injection locations based on the temperature window and mixing for effective dispersion of the reagent. However, in order to quantify No{sub x} reduction and estimate the potential for ammonia slip, a kinetic model must be coupled with the mixing predictions. Typically, reaction mechanisms for SNCR consist of over 100 elementary steps occurring between approximately 30 different species. Trying to model a mechanism of this size is not practical. This ABB project incorporated development of SNCR systems including NO{sub x} reduction and ammonia slip. The model was validated using data collected from a large-scale experimental test facility. The model developed under this project can be utilized for the SNCR system design applicable to HIPPS. The HITAF design in the HIPPS project includes low NO{sub x} firing system in the coal combustor and both selective non-catalytic reduction (SNCR) downstream of the radiant heating section and selective catalytic reduction in a lower temperature zone. The performance of the SNCR will dictate the capacity and capital cost requirements of the SCR