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Show 1 6 (4) NOx emissions are as low 10ppm or less. (5) The flame temperature distribution shows a comparatively uniform and low temperature distribution. (Fig. 26) 3.5.3 Burner application results An SLG burner was installed to the coal drying, heated-air (250°C) generation furnace when making pulverized coal for blast furnace injection and sole combustion of blast furnace gas was conducted. (Table 9) (1) Sole combustion of blast furnace gas at all operating conditions and at a turndown of up to one tenth possible. (2) Both NOx and CO emissions are extremely small (NOx< 10ppm, CO< 50ppm) (3) Stable combustion proceeds up to an air ratio of 1.05-2.5. Flame length (mm) (Temperature of furnace· 804- C) 500 , 000 , 500 E E '0 .! j 0 '0 .. ~ 2 0 4 Fig.26 Flame temper.ature distribution (120 x 103 kcal/h. Load 60%) Table 9 Application results of SLG burner Steel Works Applied Combustion Calorific Air ratio in of SMI blast furnace capacity value of fuel standard (Kcal/h burner) (Kcal/Nm3 ) operation No. 4 3,000 x 103 720 1.5 Wakayama 3 No. 5 6,100 x 10 720 1.5 Kashima No. 2 6,100 x 103 750 1.5 Kokura No. 2 1,350 x 103 650 1.5 3.6 SNM burner 2000 Application date Jan. 1986 Oct. 1991 Mar. 1990 Feb. 1989 This burner was developed for heating steel strip raidly with a reducing and direct heating flame in continuous heat treatment furnace. The burner can hp. matched to variable size of steel strip production by changing the burner load in a few second. 3.6. 1 Structure of burner The fuel ejected from the burner center pipe holes at right angles is mixed with air swirled by swirler within the burner. and the mixed fuel and air are ejected rapidly. (Fig. 27) 3.6.2 Principle and characteristics of burner If the flame does not touch to the steel strip,iron-oxide-layer of the steel strip cannot be reduced in our research. |