The process in which steel is made starts with the production of coke which is needed to produce carbon monoxide in the blast furnace after which the coke is burned in a blast furnace to produce carbon monoxide that is needed to reduce the iron oxide or hematite into carbon reduced iron, the raw ore is mixed with limestone or calcium carbonate, sinter, coke and or other aggregates, the calcium carbonate or limestone helps reduce acidic impurities in the iron and forms a layer of slag above the molten metal which is then poured or scooped carefully off the molten metal and poured back into nature. Once the slag is removed the iron is poured into a transport container or bowl where it is put into a holding furnace for later casting, the iron that will be converted to steel is transport to the next facility for the next process. The iron that is produce in this process is called pig iron and typically has a 3.5-4.5% amount of carbon or 92% in which case it is further reduced in an open hearth furnace to produce steel. There are three types of pig iron, hematite pig iron , nodular pig iron and basic pig iron in which case different types of iron can be made such as cast iron, wrought iron, nodular iron, grey iron, white iron, pig iron (directly from the furnace), and malleable iron.
http://www.steel.org/making-steel/how-its-made/processes/how-a-blast-furnace-works.aspx
http://www.bbc.co.uk/education/guides/zfsk7ty/revision/4