Ironmaking in conventional and mini blast furnaces Part 2: The mini blast furnace

摘要

The availability of raw materials and energy in the form of coke supplemented by coal/ natural gas has a major influence on the cost of hot metal produced in blast furnaces. Many innovations such as using a higher proportion of sinter in the burden, increased oxygen enrichment, operation with lower slag volumes, intense process monitoring using a variety of probes, development of mathematical models to control the process dynamics, etc have ensured that classical blast furnace ironmaking has remained competitive over many years. It continues to be the most widely used method of ironmaking even today despite the advent of such alternatives as smelting reduction (developed primarily for smaller scale application). The challenge of the alternative technologies was primarily blunted when mini blast furnaces came into the picture. MBFs are ideally suited for making special quality pig iron as well as in small-to-medium scale steel production through the EAF/ EOF route. The fact that MBFs can be installed virtually at no risk (since the process itself is well established) has gone a long way in its widespread adoption in developing countries. A large number of MBF ironmaking plants have sprung-up in the secondary sector in countries like Brazil, China and India. More such units are likely to come up in the coming five years, particularly in India.