| OCR Text |
Show formation. Further, w e noticed that the N O x value at 3 0 % load did not get lower whereas the temperature at the 3 0 % load was lower than that at the rated combustion. W e consider that this was because of poor uniformity of gas/air mixture in the case of 3 0 % load. 70 60 50 40 30 20 10 0 (HALL) • SAMPLING A (135* OOMflOM OF MJZZLO A SAMPLING C • SAMPLING 0 100 200 01STANCE FROM HALL (mm) 300 /FURNACE^ \ CENTER; FIGURE 7. DISTRIBUTION OF NOx IN FURNACE AT RATED LOAD 70 60 50 40 30 20 10 V (HALL) :^*= 4=4= • SAMPLING A (IS* OOMflOM OF tCUUD A SAMPLING C • SAMPLING 0 0.-2.4% JL Pi-6,2< 100 200 300 OrSTANCE FROM HALL (ma) /FURNACES \CENTER I FIGURE 8. DISTRIBUTION OF NOx IN FURNACE ON DIFFERET OJ % AT 30% LOAD 3)CO distribution (Figures 9 and 10) Figure 9 shows C O distribution in the furnace at rated load with O 2=3.7%. At the measuring point A at 20 m m position from the furnace wall, the maximum C O concentration was 2100 ppm, showing rapid decrease toward the center. At the measuring point C at 850 m m downstream the main nozzle, C O concentration was 55 ppm which indicated that combustion was almost finalized. The reason of low C O value at the center of point A may be because of flue gas recirculation. Figure 10 shows CO distribution in the furnace at 30 % load with O 2=2.4% and O 2=6.2%. In the case of O 2=6.2%, the maximum C O concentration at measuring point A was 1150 ppm at 20 m m 2000 1500 500 TEST CONDITIONS RATEO FIRING 0,-3.7X . N0x-43ppn(at0,-0X CORRECTEO) CO-Oopm C0.-9.94X e SAMPLING A (135* OOMflOM OF KUOQ * SAMPLING C • SAMPLING 0 0 (HALL) » t * > * fFURNACEN tCENTER^ 100 200 300 orSTANCE FROM HALL (mm) FIGURE 9. DISTRIBUTION OF CO IN FURNACE AT RATED LOAD Oi=3.7% |
