Direct Reduction Plant

Gas-based direct-reduction processes are particularly suitable for installation in those areas where natural gas is available in abundance and at economical prices.

The Midrex Process is a shaft-type direct-reduction process where iron ore pellets, lump iron ore or a combination thereof are reduced in a vertical shaft (or reduction furnace) to metallic iron by means of a reduction gas. The reducing gas is produced from a mixture of natural gas (usually methane) and recycled gas from the reduction furnace. The mixture flows through catalyst tubes where it is chemically converted into a gas containing hydrogen and carbon monoxide.The desired reducing-gas temperature is typically in the range of 900 °C. The gas ascends through the material column in the countercurrent direction and removes oxygen from the iron carriers. The product, direct-reduced iron, typically has a total iron content in the range of 90–94% Fe. After the DRI exits from the bottom of the shaft, it can be compressed in the hot condition to hot-briquetted iron (HBI) for safe storage and transportation. DRI or HBI are virgin iron sources free from tramp elements and are increasingly being used in electric arc furnaces to dilute the contaminants present in the scrap.

ASYN solutions comprise following:

  • Mass & Energy Balance Software

  • Process Basic Engineering

  • Recuperator Design

  • Level 2 Control & Automation System implementation

  • Piping Design

  • Steel Structure Design

  • 3D Modelling & Engineering Coordination

 

Hot charge of DRI into EAF

With increased charging of direct reduced iron (DRI) to electric arc furnaces to substitute for the use of expensive low residual scrap, so the benefits of charging this material hot rather than cold have been highlighted. Most DR installations now feature hot charging options or are planned so that EAF melt shops can operate with hot material charging in the future. Efficient transport of hot material with minimum temperature and dust losses and no oxidation is key to this technology.

 

Download Recuperator Design (Farsi)    

Download Direct Reduction Plant (Farsi)