Selective Noncatalytic Reduction (SNCR) Field Evaluation in Utility Natural Gas-Fired Boilers. Final Report, June 1991-March 1992.

摘要

Various technologies are available to control NOx from fossil fuel-fired power plants, ranging from combustion and operational modifications to post-combustion selective catalytic NOx reduction. One potentially attractive option for gas- and oil-fired power plants is selective noncatalytic reduction (SNCR). SNCR appears capable of reducing NOx in the 50% range. Since catalysts are not required, equipment costs are considered moderate. While the SNCR process has many attractive features, there are also several disadvantages. One drawback is the relatively narrow temperature window over which the process operates (1600-1900 deg F). This poses numerous challenges for a full-scale application since the SNCR process temperature window typically occurs in the convective section where available access space is limited, gas velocities are high, and residence times are short. Another disadvantage of SNCR is the potential emissions of undesirable byproducts (e.g., NH3, N2O, and CO). Little information is available on these issues. Recognizing the potential benefits and risks, PG&E in conjunction with the Gas Research Institute performed a field evaluation of SNCR at Morro Bay Power Plant Unit 3 (MBPP3).