By adding granulated municipal waste material to its electric arc furnace process, ArcelorMittal will be able to half the use of coal at its Hamburg electric steelworks. This will save valuable resources and further reduce CO2 emissions.
Tests with sewage sludge and paper
The innovative granulated waste product is the result of two years of development, during which a wide range of materials were examined and tested. “We tested materials as diverse as sewage sludge, paper fibers, specially prepared orange peel, and non-recyclable waste,” says Project Manager Michel Wurlitzer.
Conveyability guaranteed
German technology provider Stein Injection Technology GmbH made an important contribution to the success of the project. The company tested the materials' conveying properties with its injection technology to ensure good conveyability.
Eventually, granulated materials from municipal waste proved to be best suited as a coal substitute. The biogenic carbons contained in paper and cotton fibres, for example, and hydrogen present in this kind of waste made it best suitable for this process.
Substitute product burns emission-free
The process takes place at a steel bath temperature higher than 1,600 °C. This ensures that the municipal waste added to the steelmaking process as granules burns completely, without residues. “Our off-gas analyzes have shown that the substitute product does not cause any measurable emissions,” adds Wurlitzer.
ArcelorMittal expects that the new product made of material from municipal waste will achieve annual CO2 savings of about 3,500 t at its Hamburg steelworks. Through this, the steelmaker is making a further contribution to the decarbonization of steel production.
