A 350-kg- and 10-t-Oven Investigation into the Effects of Preheating (Followed by Gravity Charging), and Changing the Composition of, a Metallurgical Blend from the USA

摘要

Studies were carried out of a 23 10-t and numerous 350-kg-oven tests to determine the combined effects of preheating to approximately 200C and the replacement of better coking coals by poorer coals and coke breeze. It was shown that the proportion of expensive high-rank coal in the blend could be reduced or completely eliminated from the charge and replaced by 4% of fine breeze or possibly another high-rank coal. Furthermore, 29 per cent of an inexpensive low-rank coal could be incorporated in the blend. Cokes of higher than normal strength could be obtained by preheating charges that contained 4 percent fine breeze and 8 percent Beatrice or Premier coal and, to a lesser extent, by adding 8 percent Beatrice or Premier coal or fine breeze. Preheating increased the charge bulk density, reduced the carbonizing time and increased coal throughput by 40 to 50 per cent.