Displaying items by tag: research

US: Novel concretes developer Greencraft has made a patent application for a new method of CO₂ mineralisation using a microporous material containing mineral oxides, like slag. Global Warming Focus News has reported that the method also works for natural hyaloclastite, bottom ash, fly ash, volcanic ash and lava.

Greencraft said that its method marks an ‘improvement’ in current techniques for sequestering CO₂ in alternative materials.

China: A new study from Hong Kong Polytechnic University showcases sustainable cement production methods, focusing on low-clinker cements and alternative solutions for incinerator fly ash (IFA). The research demonstrates that using carbonated-washed IFA mixed with slag, coal fly ash, or metakaolin can replace 60% of Portland cement, forming ternary blended cement. This approach reportedly reduces the carbon footprint of cement production.

The study found that slag was the most effective,improving pore structure and increasing ettringite and hemicarboaluminate formation with a blend of 40% slag and 20% IFA. It achieved 90% of the compressive strength of pure Portland cement after 90 days.

The researchers said "This study demonstrated the promising potential of the blended cements to simultaneously divert IFA from landfills and reduce the clinker content of cement."

US: The Department of Transportation has announced a US$5m initiative to investigate the use of steel slag in cement and concrete. This will take the form of a collaboration between the Department of Transportation and a selected US-based steel producer and university partner. The initiative seeks to reduce CO₂ emissions in the production of building materials. Prospective participants may view the grant opportunity here.

Transport secretary Pete Buttigieg said "We're proud to make this funding available to help develop the next generation of construction materials so that the future of our transport infrastructure is more resilient, more sustainable and made in America.”

Robert Hampshire, deputy assistant secretary for research and technology and chief science officer, said “This funding initiative will develop and advance innovative materials and technologies that support the nation’s goals to decarbonise the transportation sector by 2050, strengthen resilience of the nation’s transportation infrastructure, and address adverse environmental impacts created by the transportation system.”

Finland: Betolar has signed a cooperation agreement with concrete producer Consolis Parma to develop reduced-CO₂ hollow concrete slabs. The development process will implement Betolar's Geoprime binder into Consolis Parma's concrete production. Consolis Parma is committed to halving its CO₂ emissions between 2021 and 2035.

Consolis Parma's Technology Director Juha Rämö said “The use of alternative new binder combinations and additives that ensure the efficiency of the manufacturing process are key factors in achieving our climate goals. We are actively seeking new channels to address these challenges. The cooperation with Betolar is an important new partnership for us."

Germany: Building materials research institute FEhS-Institute says that cement producers used 7.9Mt of German ground granulated blast furnace slag (GGBFS) in cement production in 2022. This corresponds to 71% of the 11.1Mt of slag produced by the domestic iron and steel industries during the year. Other applications for the slag included aggregates production (3.1Mt - 28%) and internal recycling at the refinery (500,000t - 4.5%).

Managing director Thomas Reiche said "Unlike recycled materials, iron mill slags are already high-quality and climate-friendly secondary raw materials in their 'first life.' For decades they have made an important contribution to a sustainable recycling economy in Germany. To ensure that this can continue in the future after the transformation of the steel industry, we have been researching new slags together with our partners since 2013 - for example, with the Direct Reduction Of Iron Ore Electric Furnace Slag and Save CO2 projects to develop Blast Furnace Slag 2.0."

UK: SteelPhalt, a subsidiary of US-based Harsco Environmental, has been awarded a research grant through the Industrial Energy Transformation Fund (IETF). The grant is part of a government effort to distribute funding to help energy-intensive industries cut their carbon emissions and energy costs. The grant funds will enable the company to conduct a feasibility study on energy-efficient solutions for asphalt production. The research will seek to identify ways to capture the waste heat in the exhaust gases and transform it into electrical power, with the objective of reducing the energy demand and carbon impact of the process. The company uses steel slag as a main component of its asphalt products.

UK: A team of researchers from six UK universities has filed a patent for a clinkerless cement product called Cambridge Electric Cement. Local press has reported that the project, called UK Fires, saw researchers successfully produce the cement using renewable power from recycled cement powder and ground granulated blast furnace slag (GGBFS). Following its successes, UK Fires has obtained a further Euro2m in funding from the UK Engineering and Physical Sciences Research Council (EPSRC) to continue its work into the range of concrete wastes suitable for use in Cambridge Electric Cement production.

US: The Slag Cement Association (SCA) has announced the recipients of its 2021 Slag Cement in Sustainable Concrete Awards program. Thirteen construction projects were chosen to showcase the broad applications of slag cement and its impact on creating more durable and sustainable concrete. The infrastructure winners included projects with slag cement supplied by companies including Argos USA, Cemex, Lehigh Hanson, Ozinga, Skyway and St Mary’s Cement. These projects included work on roads, bridges, residential construction, a concert venue, a sport stadium, airports, a theme park and a hydroelectric dam. Two research projects on slag cement from Cleveland State University and Florida State University were also recognised.

Japan: JFE Steel and Innoqua, a startup linked to the University of Tokyo, are working on using slag as an artificial bed for coral reef restoration. JFE Steel has recently installed a 1m fish tank in the lobby of its Tokyo-based headquarters as part of a feasibility test for the biodiversity initiative, according to the Nikkei newspaper. The companies are testing Marine Block, a product made from slag that is processed using a proprietary technique to allow coral to attach to it easily. The initiative will examine which species of corals are most likely to attach to the Marine Block, the ideal growing conditions and then move on to larger-scale coral breeding.

The Japanese steel industry produces over 35Mt/yr of slag. The majority of it is used in infrastructure projects. JFE Steel hopes to use about 10% of the slag it produces in 2030 in port and marine applications.

Vietnam: The government has encouraged cement producers to increase their uptake of waste products, including slag, in cement production. The Viet Nam News newspaper has reported that the government has asked the Ministry of Construction and related agencies to complete the formulation of technical standards, regulations and instructions in relation to the use of slag as well as researching new applications for it. The Ministry of Industry and Trade has also started inspecting storage sites to ensure that it doesn’t exceed two years worth of production. The government initiative has been made in response to rising stockpiles of slag, ash and gypsum.