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VITO – CO2 negative construction materials from recycled resources
EARTO Innovation Awards 2016 – Impact Expected Category
Third Prize

The steel industry produces massive quantities of waste materials with no or at best low-value applications, creating serious environmental issues. On the other hand, the construction industry is responsible for a large amount of global CO
2 emissions and drastically needs to improve its environmental impact. To address these two problems, EARTO member VITO developed the Carbstone process that transforms waste materials and CO
2 into high value construction materials with drastically reduced environmental impact.
In the steel industry, massive quantities of alkaline waste materials such as steel slags or construction and demolition waste are produced each year. For instance, 170-250 million tonnes of steel slags were produced worldwide in 2014. Besides, in the construction industry, concrete assumes an eminent role with a production of 30-35 bn tonnes/year, making it the second-most used material by mankind behind water, while concrete manufacturing is responsible for up to 8% of global CO
2 emissions. A better and more efficient processing of alkaline waste and CO
2 into high value products therefore provides large environmental benefits.

The market targeted by Carbstone is
estimated to grow by up to 1.2% /year, reaching 16bn tonnes by 2050
Significant economic value:
€335m investments and
17.500 jobs
Considerable environmental impact: 10m tonnes
CO2 reduction and
40m tonnes waste recycling
Breakthrough technology
VITO’s Carbstone process transforms alkaline waste and CO
2 into high value construction materials. The process uniquely combines existing technologies, using accelerated mineral carbonation by treating various types of waste with CO
2 at elevated pressure and temperature. The CO
2 is sequestered inside the products by transforming CO
2 gas into solid carbonate minerals that cement the slag particles together. This flexible technology allows for the production of a range of products, from paving bricks to roofing tiles, with the same technical properties as conventional concrete products.
Reduced environmental impact
Carbstone’s considerable environmental benefits turn this technology into a disruptive innovation. Indeed, Carbstones have a negative CO
2 footprint, 200kg CO
2/kg lower than conventional concrete construction products, mainly due to a highly energy-efficient production process and the incorporation of CO
2 inside the materials. CO
2 emissions are also avoided by a decreased use of primary raw materials. Besides, around 800kg of secondary raw materials can be recycled to produce a tonne of Carbstone material, an extremely high ratio compared to the 28% substitution rate of current concrete based construction materials. Carbstones therefore avoid landfilling, save on primary raw materials and reduce global warming.
From pilot to market
To further develop this patented technology, a pilot plant was created in 2014 and large-scale industrial trials are conducted. The target is to set up a production plant for the Belgian market in 2017, while developing a licensing model to commercialise the technology worldwide. The market targeted by Carbstone is estimated to grow by 1.2%/year, reaching 16bn tonnes by 2050. The “breakthrough scenario” estimates a production of 50m tonnes of Carbstone by 2040, while recycling 40m tonnes of waste and saving 10m tonnes of CO
2, with a total investment of €335m and 17.500 full-time jobs created.
More information about this innovation
VITO is a Belgium RTO in cleantech and sustainable development, elaborating solutions for the large societal challenges of today. This results in 5 research programmes: sustainable chemistry, energy, health, materials management and land use. Each programme builds up a strong base of knowledge and skill, with added value for industry and society. The 750 employees are working hard on sustainability and transition thinking as binding factors between the 5 research programmes.
www.vito.be