Australian technology that harvests blast furnace waste from steel production and uses it to make greener cement is being trialled at industrial scale in China, the world’s largest iron user.
The sustainability potential for the technology is immense. If fully commercialised, it has the potential to save each year 60 billion litres of water, 800 petajoules of energy and 600 million tonnes of greenhouse gas emissions. This is equivalent to 14 per cent of Australia’s entire energy use, and about 10 per cent of its annual greenhouse gas emissions.
The process, know as Dry Slag Granulation, is subject to an agreement signed by CSIRO and the Beijing MCC Equipment Research & Design Corporation, and is a landmark for both Australia-China research collaboration and environmentally friendly metal production, according Jonathan Law, director of CSIRO’s Mineral Resources Flagship.
“Our collaboration is an exciting step towards the uptake of an innovation with real prospects of transforming the productivity and environmental performance of global iron smelting,” Mr Law said.
“The benefits from wide uptake of DSG technology on blast furnaces will be profound in helping the global industry to reduce water and energy use and greenhouse gas emissions while sustaining metal production.”
The DSG technology is fitted to blast furnaces and includes a spinning disc and granulation chamber that separates molten slag into droplets under centrifugal forces. Air is used to quench and solidify the droplets, with a granulated slag product being extracted as well as heated air, which can be captured for reuse onsite in applications such as drying, preheating or steam generation.
The process produces a “glassy” product ideal for cement manufacture, but with significantly lower associated greenhouse gas emissions than conventional cement production.
The technology also saves water and eliminates the underground water pollution associated with alternative wet granulation processes.
Under the agreement MCCE will scale-up and demonstrate the technology at industrial scale and, if successful, commercialise it in China, which produces 60 per cent of the world’s iron waste, before potentially taking the technology global.
The agreement is the culmination of more than a decade of DSG technology development by CSIRO and industry partners including Arrium and BlueScope.
“DSG is just one of the CSIRO innovations in sustainable steel production and one of many solutions we have found for national and global challenges in the minerals industry,” Mr Law said.
“The DSG project is a good example of reward from continuous R&D investment and we look forward to working closely with MCCE to bring it to full fruition.”
Australia is set to benefit immensely from the DSG technology, as it is owned by the CSIRO, which has two patent applications for it. Unfortunately, research into mineral resources and energy was worst-hit by the $115 million Abbott Government budget cuts to the CSIRO, according to The Australian. Resources and energy is one of five “areas of strength” identified by Australian federal and state/territory governments as foreign investment priorities, it said.