ABSTRACT
The Chapter covers a brief description on the iron-making processes and their correlations with the quality parameters of ferruginous burden materials: iron ore in lump form and agglomerates in the form of sinter and pellets. The integrated blast furnace and oxygen steel-making route happens to be a dominant process for steel production worldwide. The rest is contributed through the (a) coal- and gas-based direct reduced iron production route, also (b) smelting–reduction process for production of liquid iron, like COREX smelting reduction technology. Their performance in terms of (a) productivity, (b) cost of operation, and (c) hot metal quality has been briefed. Iron making through the blast furnace route is a highly capital intensive operation, which is specifically mentioned in the text. The reduction of iron oxide, as it descends axially in the blast furnace, takes place in stages and in its various zones; related phenomena and chemical reactions are outlined. The countercurrent principle on which the blast furnace operates makes it rely heavily on the agglomerates' properties: strength, reduction behavior, also the meltdown characteristics. The quality requirement of burden materials across the different sections of the blast furnace varies; these are mentioned in the text. The importance of maintaining adequate gas permeability in its upper shaft, also of liquid and gas permeability in its lower part, is described. The slag has desulfurization capacity; its role in maintaining the hot metal quality is outlined. In an integrated iron and steel plant, the performance of a sinter and/or pellet plant should be seen in combination with that of the iron making. It is not only the quantity of agglomerates but their quality that matter.
