COREX® Smelting Reduction Process

COREX®, a smelting-reduction process, enables the cost-effective and environmentally friendly production of hot metal from iron ore and coal. By eliminating the need for coke ovens and sintering plants and utilizing lower-cost coal compared to the blast furnace route, the COREX® process achieves significant cost savings of up to 15% compared to the conventional blast furnace route. COREX® plant emissions contain only insignificant amounts of NO_X, SO₂, dust, phenols, sulfides, and ammonia. Thus, emission values fall far below the maximum values permitted by, e.g., European standards. Furthermore, wastewater emissions in this smelting reduction route are considerably lower than in the conventional blast furnace route.

Advantages of the COREX® Process

Direct Use of Non-Coking Coal

In the COREX® process, all metallurgical work is carried out in two separate process reactors: the reduction shaft and the melter gasifier. As the burden pressure in the melter gasifier is lower compared to the burden pressure in a blast furnace shaft, it allows coal to be charged directly into the melter gasifier, enabling the use of non-coking coal and eliminating the need for a coking oven plant.

A High Proportion of Lump Ore

The typical burden for COREX® is 100% pellets. Depending on the price of lump ore available, a lump ore ratio of up to 80% is also possible without interfering with the stable production of the plant.

Use of Pure Oxygen

Blast furnace operators strive to enrich the hot blast with oxygen, as the high ratio of nitrogen in the hot blast is a burden for the blast furnace process. The COREX® process uses high-purity oxygen, producing a top gas with a high calorific value. This gas can subsequently be used for further reduction work, heat/energy generation, or to produce ethanol and acid using gas fermentation processes, such as the proprietary fermentation process from LanzaTech. Since each steel production plant is unique, the additional value generated from top gas can be suited to each customer's particular needs.