Evaluation of NOx reduction alternatives for coal fired boilers

The Clean Air Act Amendments (CAAA) of 1990 for the first time contained provisions for reduction in nitrogen oxides (NOx) emissions from existing stationary sources. NOx emission limits have been published with both the federal government and individual states and regions issuing their own guidelines. A complex compliance schedule is influenced by the location of the source, the type of source and the fuel fired. Developing an acceptable emission compliance plan is a complex process, especially when the operation of multiple sources must be considered. NOx emission reduction options include both combustion and post combustion retrofits and the viability and effectiveness of these must be evaluated both individually and in combination. An accurate estimate of baseline emissions is also required in order to develop a meaningful compliance plan. Once the viable control options are identified, implementation cost estimates must be developed and the cost effectiveness of alternate NOx reduction options compared. This process should result in a minimum cost NOx compliance plan.