The production process of direct reduction of iron can be roughly divided into processes based on H2 as a reducing agent and processes based on C as a reducing agent.
Gas based vertical furnaces belong to non melting direct reduction iron. The main technologies on the market are Midrex and Energiron.
The gas based reduction process based on a vertical furnace provides an efficient method for reducing iron oxide with great operational flexibility. The operation of the reduction shaft furnace is simple and direct. Iron containing materials (ball or block ore) are introduced into the top of a cylindrical refractory lined container, descending by gravity flow and coming into contact with the upward flowing reducing gas. Reducing gases (mainly hydrogen and carbon monoxide) react with iron oxide to reduce (remove oxygen content) and carbonize the material before unloading. Products can be simultaneously made into CDRI, HDRI, HBI, or any combination.Our company, in cooperation with HYL/Midrex, has successfully put into operation the 600,000 ton per year gas based direct reduced iron project at Hebei Zhangxuan High tech Technology Co., Ltd., a subsidiary of Hebei Zhangjiakou HBIS Group. This production line adopts the Energiron gas based reduction process and draws on Midrex, which has the characteristics of high metallization rate, high production efficiency, high energy utilization rate, high DRI strength and density. It has become the world's first hydrogen rich gas (coke oven gas) direct reduction equipment. Currently, the production and operation are stable, and the product quality and output meet the standards. With carbon dioxide emissions as low as 250 kilograms per ton of reduced iron, Zhangxuan High Tech will become the world's lowest carbon industrial direct reduction plant.
