Iron. 7. 118 smelting

An additive assisting in fusion - e.g. CaCOj in iron-smelting - although the limestone also helps with slag formation. 

From this relationship it can be seen that a reduction level of 95% compares with a metallisation level of 92.5%. A reduction level of 33.33% or less has a metallisation level of 0%. DRI normally has at least 90% reduction or 85% metallisation. Processes producing soHd, partially reduced iron, ie, <90% reduced or <85% metallised, are classified as prereduction processes. The partially reduced product, called prereduced iron, is not acceptable for steelmaking but can be used as a feed for iron smelting. 

Blastfurnace slag Iron smelting Nearly all used As roadstone, railway ballast, filter medium, aggregate for concrete, fertilizer and in manufacture of cement... 

Blastfurnace slag Iron smelting Nearly all used As roadstone, railway... 

The iron smelting process in the blast furnace is a classic example worth mentioning in order to illustrate some general features of waste heat recovery. With respect to the combustion of its fuel and the resultant formation of gases, the iron blast furnace is like a huge gas producer. There is always an excess of carbon in the combustion zone, and the product formed in it is carbon monoxide. There is, of course, no steam blown in as such, but whatever moisture is present in the blast is decomposed by carbon, as in creating producer gas ... 

HIsmelt A direct iron smelting process in which noncoking coal, fine iron ore, and fluxes and gases, are injected into a molten iron bath the carbon monoxide produced is used to prereduce the ore in a fluidized bed. Under development by CRA, Australia, since the early 1980s, joined by Midrex Corporation in 1988. Their joint venture company, Hismelt Corporation, commissioned a pilot plant at Kwinana, near Perth, Australia, in 1993. 

The importance of coal started to be recognized when it was tried as a fuel in brick ovens. An extensive use of coal began in the middle of the 17rh century when Engl ironmaster Dudley established several iron smelting works for which coal was more suitable than charcoal... 

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