DRI Sponge iron or direct reduced iron (DRI) is a material obtained from the reduction of iron ore (in the form of lumps, pellets or slag) directly, that is, without smelting. During the direct regeneration process and due to the release of oxygen gas, the iron ore turns into spherical pieces that have small holes on their surface like a sponge. This appearance is the reason for the special name of this product. The grade of sponge iron is between 84 and 95%, which is a high value. Among the reasons for the spread and popularity of sponge iron, we can mention the lack of iron waste, its price increase and environmental problems. Iran is the second largest producer of sponge iron in the world.