Cost of Selective Catalytic Reduction (SCR) Application for NOx Control on Coal-Fired Boilers

摘要

The report provides a methodology for estimating budgetary costs associated withretrofit applications of selective catalytic reduction (SCR) technology on coal-fired boilers. SCR is a postcombustion nitrogen oxides (NO-x) control technology capable of providing NO-x reductions >90%. With SCR, NO-x reductions are achieved by injecting ammonia into the flue gas, which then passes through layers of catalyst in a reactor. The ammonia and NO-x react on the surface of the catalyst, forming nitrogen and water. In the U.S., SCR has been applied mainly to electrical utility boilers firing coal and natural gas and ranging in capacity from 25 to 800 MW. The costing methodology presented in the report applies to SCR retrofits on coal-fired boilers ranging in capacity from 100 to about 850 MW and with design efficiencies >80% and up to 95% of NO-x removal. The cost equations and variables used in the methodology are based on information from SCR system suppliers and reflect experience gained from >200 SCR applications. Note, however, that the budgetary cost estimates for typical SCR applications that this methodology can provide cannot replace the detailed site-specific engineering cost studies or cost quotations that are developed by SCR systems suppliers.