Effect of Size Distribution of Coke Breeze on Sintering Performance

Coke breeze is added as fuel in sintering process. The size distribution of coke breeze is one of the important factors, which plays an important role in achieving proper sintering process. Therefore, the effects of size distribution of coke breeze on sintering performance are investigated. Experimental results show that, in practical production, we should adjust the size distribution of coke breeze according to the different production strategy (aimed for best strength or highest productivity, or others). For example, aimed for sinter with maximum tumble strength, the size distribution of coke breeze should be 57.20% of −1 mm, 25.63% of 1–3 mm, 11.17% of 3–5 mm, and 6.00% of +5 mm. Then the tumble strength of sinter increases about 1.48%, production yield increases about 1.7%. Similarly, aimed for sinter with maximum productivity, the size distribution of coke breeze should be 47.22% of −1 mm, 23.10% of 1–3 mm, 28.68% of 3–5 mm, and 1.00% of +5 mm. For this case, the productivity increases 0.1 t m−2 h−1, the sintering speed increases 0.7 mm min−1, and the production yield increases 0.4%. There are two reasons for that sinter B (optimized by maximum tumble strength) has better sintering performances, they are as follows: (i) the effect of coke breeze size on the sintering temperature profile and (ii) pores distribution. The research results of present work could give a scientific guide to reasonably utilize fuel resources in practical sintering process. In case of practical sinter production, the time of high temperature zone (+1200 °C) is relatively lower, thermocouple 1 and thermocouple 2 are 170 and 330 s, respectively. While in case of maximum tumble strength, they are 190 and 370 s, respectively. Therefore, the effect of coke breeze size on the sintering temperature profile is the essential for sintering performances.