The Materials Processing Institute, in collaboration with industry and research partners, has secured a £118,363 research project to investigate methods of converting steelmaking slag into high-grade road surfacing material.
This research is supported by a government grant awarded by Innovate UK, the UK’s innovation agency, as part of the Transforming Foundation Industries initiative.
It is the latest vote of confidence in the Teesside-based research and innovation centre and comes just weeks after it was awarded £22m by chancellor Rishi Sunak to deliver a five-year programme aimed at revolutionising the steels and metals sector.
Steelmaking slag is currently crushed and used in the road construction process, but its currently approved 60 PSV level of skid resistance limits use on UK roads accordingly.
The institute is collaborating with Tarmac, British Steel, Glass Futures and PWS road building services. The 12-month project will seek to increase the silica content of the slag, which is a by-product of basic oxygen steelmaking (BOS), to improve its quality and consistency and achieve a higher PSV classification which would allow greater use on UK roads and reduce waste through reuse of the refined slag.
The institute will investigate using slags produced in other areas of the steelmaking process, including desulphurisation slag, which is difficult to dispose of. It will also conduct research into the waste streams produced by the glass industry that cannot be recycled.
Its objective is to create several new slags modified by high silica sources, which will be tested by Tarmac for skid resistance. The most promising will be produced in a full-scale plant trial before undergoing further testing.
The second activity of the project is to undertake a detailed assessment of the volumes and values of waste, or difficult-to-reuse, streams of appropriate material from within the glass industry and the steel works to determine the potential for use as a slag modifier.
The research aims to improve the utilisation of by-product and waste streams to increase the value and volume of the by-product stream thereby benefitting both the steel sector and the aggregates sector. It will reduce the current rate of consumption of high quality aggregate, with environmental and balance of payments benefits.
The research will improve the competitiveness of the steel industry by increasing the value and quantity of a by-product by the addition of difficult to recycle materials and it will help the glass industry to deal with ‘difficult to recycle’ materials. It will improve the competitiveness of the aggregate industry by replacing high cost imported aggregate.
Cross sector collaboration was central to this grant being awarded. The Materials Processing Institute will design, produce and analyse the modified slags at the required scale, British Steel will supply the modifier materials in the appropriate crushed form, Tarmac will carry out the testing and scale up trials, Glass Futures will assess the volumes and values of waste, or difficult-to-reuse, streams of appropriate material from within the glass industry and PWS Road Building Services will guide the test programme and will facilitate acceptance within the road construction sector.
Chris McDonald, chief executive of the institute, said: “We are delighted to have been awarded the funds for this innovative project that will seek to repurpose materials that are either already destined for landfill or difficult to reuse.
“The UK steel industry produces around 550,000 tonnes of coarse steelmaking slag annually. A commercially viable material will reduce waste, contribute to the circular economy and increase the competitiveness of the steelmaker, glass producer and material processor.
“We are confident this investment will pay dividends for the UK economy and further enhance this country’s expertise in research and innovation.”