Development of advanced NO{sub x} control concepts for coal-fired utility boilers. Quarterly technical progress report No. 4, July 1, 1991--September 30, 1991

CombiNO{sub x} is a NO{sub x} reduction process which incorporates three different NO{sub x} control technologies: reburning, selective non-catalytic reduction (SNCR), and methanol injection. Gas reburning is a widely used technology that has been proven to reduce NO{sub x} up to 60% on full-scale applications. The specific goals of the CombiNO{sub x} project are: 70% NO{sub x} reduction at 20% of the cost of selective catalytic reduction; NO{sub x} levels at the stack of 60 ppm for ozone non-attainment areas; Demonstrate coal reburning; Identify all undesirable by-products of the process and their controlling parameters; Demonstrate 95% N0{sub 2} removal in a wet scrubber. Before integrating all three of CombiNO{sub x}`s technologies into a combined process, it is imperative that the chemistry of each individual process is well understood. Pilot-scale SNCR tests and the corresponding computer modeling were studied in detail and discussed in the previous quarterly report. This quarterly report will present the results obtained during the pilot-scale advanced reburning tests performed on EER`s Boiler Simulation Facility (BSF). Since methanol injection is a relatively new NO{sub x} control technology, laboratory-scale tests were performed to better understand the conditions at which methanol is most effective. The experimental set-up and results frommore » these tests will be discussed.« less