Catalytic reduction of nitrogen oxides with ammonia: utility pilot plant operation. Final report, Jan 1973--Oct 1976

The report describes work to demonstrate, on a utility pilot plant scale, the performance, reliability, and practicability of reducing nitrogen oxides (NOx) emissions from steam boilers by reduction of NOx with ammonia over a platinum catalyst. A utility pilot plant treating a slipstream from an operating electric utility boiler, equivalent to approximately 1.5 MW output, was designed, installed, and tested on gas and oil fuel. Laboratory pilot plant testing supplemented the utility pilot plant testing. Results of gas-firing the utility pilot plant, together with laboratory pilot plant test results, indicated that the catalytic reduction system has consistently provided 85-90% NOx removal for over 4000 hours, with no significant performance loss at a 50,000 per hour space velocity. Results of oil-firing the utility pilot plant, together with laboratory pilot plant tests results, indicated that this system could provide at least 65% NOx removal when the flue gas temperature is above 575 F. Preliminary cost estimates indicate a capital expenditure of less than $11 per kW plant capacity, with an operating expenditure of less than $0.02 per kWhr for a full-scale system, based on 1974 dollars and a gas-fired 480 MW plant.