HIsmelt™: Reducing Costs and Emissions
At an 800,000-tonne-per-year capacity plant in western Australia, Nucor is part of a joint venture using HIsmelt™ technology to produce high quality pig iron while actually reducing greenhouse emissions and costs.
Pig iron, mainly produced as feedstock for steel mills, is typically made using blast furnaces that consume huge amounts of coal to create and burn coke.
But with HIsmelt technology, front-end processes like coke and sinter making are eliminated. Not only that, the process is able to use cheaper iron ore fines and coal fines to add efficiency to its innovation.
Since most air and water emissions are directly related to the volume of coke produced, entirely eliminating coke production is extremely beneficial for the environment.
At the heart of HIsmelt technology is the Smelt Reduction Vessel (SRV), which replaces the function of a blast furnace. Essentially, the SRV is able to generate huge amounts of energy, which can instantly transfer carbon from the coal fines into the melted iron fines to produce iron.
With the technology, a HIsmelt plant will have lower than industry best practice emissions of CO2, SO2 and NOx. Plus, many of the wastes produced during the process can be recycled in an efficient manner. Its slag can be used for a variety of applications in construction. And its offgas can be used a fuel for power generation.
WITH THE TECHNOLOGY, A HISMELT PLANT WILL HAVE LOWER THAN INDUSTRY BEST PRACTICE EMISSIONS OF CO2, SO2 and NOx.
In addition to decreasing greenhouse emissions, the HIsmelt process will provide cost-effective steelmaking options for developing countries and replacement for aging plants in developed countries.
As for the pig iron end-product? It's relatively free of impurities and is easily re-melted and processed for conversion to high-grade steel.