TECHNOLOGY & PRODUCTS
Cold Direct Reduced Iron (CDRI)
Cooled DRI for flexible handling and charging
Cold Direct Reduced Iron (CDRI) is the most common discharge configuration used in MIDREX™ Plants.
After reduction, the iron is cooled and passivated, allowing it to be safely handled, transported, stored and charged into steelmaking furnaces as needed.
This flexibility makes CDRI well-suited to plants where ironmaking and steelmaking operations are not directly connected or where material logistics require storage and transport.
What is CDRI?
Most MIDREX Plants built to date produce CDRI. After reduction, the DRI is cooled in the lower part of the MIDREX™ Shaft Furnace to about 50°C. CDRI is typically used in a nearby electric arc furnace (EAF).
The material is passivated to prevent reoxidation and loss of metallization. Once it has cooled, it can be conveyed and stored for a short duration, with the appropriate material-handling systems. CDRI is most often used in operations where flexibility in material handling matters more than immediate energy recovery. Because hot transfer is not required, plant layout and transfer distance tend to be less restrictive than in hot-charging configurations. This can simplify material flow, particularly at sites where ironmaking and steelmaking units are not tightly integrated.
MIDREX CDRI Plant in Hamburg, Germany. Start-up: 1971
CDRI in steelmaking
In electric arc furnace steelmaking, CDRI is used across a range of charging practices, including continuous charging. Its handling behaviour is familiar to operators and fits well with variable production schedules and day-to-day process adjustments.
Multiple iron product forms
The MIDREX™ Process allows iron to be produced in multiple forms, so producers can align the product form with layout, logistics, and operating priorities.
Many MIDREX Plants are configured to produce more than one iron product form, or to move between forms as operating needs change. In this context, CDRI serves as a baseline product that can be handled or stored with relatively few constraints.
World DRI Statistics
Examine the latest annual data, production figures and global trends in direct reduction.