Direct Reduced Iron

The industrial production of iron starts with iron ore, a naturally occurring mineral. Chemically, iron ore consists of iron and oxygen, mostly in the form of magnetite (Fe3O4) or hematite (Fe2O3). That oxygen is traditionally removed in a blast furnace by combining it with carbon. Alternatively, the oxygen can be combined with hydrogen or carbon via a process known as direction reduction of iron, or DRI for short. Both routes produce impure forms of iron which requires further processing to yield usable iron and steel products.

The direct reduction of iron (DRI) is a more energy efficient route to produce iron from iron ore than the traditional blast furnace. Moreover, if hydrogen is used as the reductant instead of carbon, then DRI can eliminate the formation of carbon dioxide, seen as a major contributor to global warming.

After production, direct reduced iron (DRI) will immediately start to re-oxidise. This process emits energy in the form of heat, creating a risk of self-combustion. Hence when shipped, DRI is often kept under nitrogen, which is an inert gas. Re-oxidation can be slowed by processing DRI into larger forms, such as briquettes. In many cases, the DRI unit is part of an integrated facility, whereby all DRI is quickly processed further into more stable forms of iron and steel.