FASTMET® uses a rotary hearth furnace (RHF) to convert steel mill by-products and iron oxide fines to a highly metallized DRI. These by-products typically include iron oxide screenings, baghouse dust and mill scale. Carbon contained in the wastes or added as coal, charcoal, or coke is used as the reductant. The iron-bearing materials, reductant and a binder are mixed and either pelletized or briquetted.
The pelletizing option uses a pan system, with the pellets dried at 160-180oC, then fed to the RHF. For briquetting, a roller press is used and the briquettes are fed directly to the RHF without curing or drying. Generally briquetting provides for more flexibility when using the wide range of chemistry and particle sizes encountered with steel mill wastes.
The FASTMET® RHF Process has been fully developed and numerous commercial-scale plants are operating in Japan, offering a cost-effective means of dealing with ferrous and non-ferrous by-products from iron and steelmaking processes.
FASTMELT® utilizes the same basic flowsheet and equipment as FASTMET® but includes a melter to produce hot metal. Hot DRI is discharged from the RHF and melted in an electric furnace or coal-based melter.
FASTMET®/FASTMELT® is now available for commercial sale by Midrex Technologies and Kobe Steel.