OCR Text |
Show E Q. Q. >i 0 Z Fig. 4. Effect of FGR on NOx. QLN in the Test Facility 20 -~------~~~----~--~~~--~~~30 E 15 Q. +-___ --+_~---.,;;~- __ ~=_---:... ___ -~--=:..-==:...&_ 20 ~ • NOx, ppm o • CO, ppm U 10 -. r--------T------~_r----~~~--~~~ 10 5 -~ .. ~.- ~ - --~ '.'- -':(, -~ .. --:-. ~--~_~~_~--------___ --~.~ .- -~~------~o o 5 10 FGR, 0/0 15 20 OUTLINE OF BENCHMARK INSTALLATIONS AND THE RESULTS The following describes the results achieved with QLN burners in some applications that together present the overall picture of the burner performance. 1. United Airlines, San Francisco CA - retrofit of a 75,000 pph B&W packaged boiler. The burner was firing natural gas, and jet fuel with up to 95 MMBtu/hr capacity. This was the first field installation of QLN burner mentioned earlier. All of the existing combustion controls and the fan were reused. When firing Natural Gas, NOx emissions below 30 ppm were easily achieved with 15% excess air and no FGR, Fig. 5. Carbon Monoxide emissions at the back of the furnace were about 50 ppm, but reaching 300 -400 ppm at the stack due to shortcircuiting . When firing jet fuel NOx was up to 75 ppm. 2. Nerefco, Netherlands - this was the first retrofit of a field erected boiler with two QLN burners, manufactured by COEN Dejong, a subsidiary of COEN in Holland. The boiler had relatively low space heat release, typical for European boilers. Overall firing rate was 235 MMBtu/hr. Combustion air was at slightly elevated temperature. The results were 26 ppm NOx, 13% excess air and insignificant CO emissions without FGR. 3. Gaylord Container, Antioch CA . This job is a good example of QLN performance in a large field erected boiler equipped with four QLN burners firing up to 480 MMBtu/Hr. The results were 42 ppm NOx, at 15% excess air ard practically no CO emissions without FGR. 4. Extremely low NOx emissions of 14 ppm were achieved in the eight feet diameter Steam Flood Generator (Bakersfield, Ca) firing Natural Gas at up to 60 MMBtu/Hr. The furnace was almost equivalent to the Coen test facility where all the initial testing with QLN was performed. The reduction in NOx versus data at the test yard are attributed to the absence of refractory lining in the Steam Flood Generator. 6 |