What is corex technology in steel making and why it is called so?

Corex is a smelting-reduction process developed by Siemens , for the cost-efficient and environmentally friendly production of hot metal from iron ore and coal. The process differs from the conventional blast furnace route in that non-coking coal can be directly used for ore reduction and melting work, eliminating the need for coking plants. The use of lump ore or pellets also dispenses with the need for sinter plants. All metallurgical work is carried out in two separate process reactors - the reduction shaft and the melter gasifier. Lump ore, sinter, pellets or a mixture are charged into a reduction shaft where they are reduced to direct-reduced iron (DRI) by a reduction gas. Discharge screws convey the DRI from the reduction shaft into the melter gasifier where final reduction and melting takes place in addition to all other metallurgical and slag reactions. Corex is a smelting-reduction process developed by Siemens , for the cost-efficient and environmentally friendly production of hot metal from iron ore and coal. The process differs from the conventional blast furnace route in that non-coking coal can be directly used for ore reduction and melting work, eliminating the need for coking plants. The use of lump ore or pellets also dispenses with the need for sinter plants. All metallurgical work is carried out in two separate process reactors - the reduction shaft and the melter gasifier. Lump ore, sinter, pellets or a mixture are charged into a reduction shaft where they are reduced to direct-reduced iron (DRI) by a reduction gas. Discharge screws convey the DRI from the reduction shaft into the melter gasifier where final reduction and melting takes place in addition to all other metallurgical and slag reactions.