Displaying items by tag: Slag

Sweden: Cemvision has developed a patent-pending beneficiation process to upcycle electric arc furnace (EAF) and basic oxygen furnace (BOF) slags into high-performance supplementary cementitious material (SCM), while recovering valuable metals.

Third-party testing found the material performs as well as or better than ground granulated blast-furnace slag (GGBS). Cemvision recovers 99% of the iron oxide content from EAF slag for reuse in steelmaking, as well as other metals like chromium.

The output will support Cemvision’s Re-Ment Massive and Rapid products as clinker-replacing SCMs. The process was piloted with metallurgical research institute Swerim.

Cemvision CEO Oscar Hållén said “This is a game-changer not only for the cement industry but for steel producers as well. Our process enables high-performing cement products from materials that would otherwise be treated as waste. With this innovation, we're proving that decarbonisation and circularity can go hand in hand, and at scale.”

US: Researchers at the Massachusetts Institute of Technology (MIT) have developed an AI tool to compare studies of alternative raw materials for cement production. A collaborative team from the MIT Concrete Sustainability Hub and MIT’s recycling research programme, Olivetti Group, published its findings in the Nature journal. The team mined 5.7m academic publications to identify 14,434 alternative raw materials. These belonged to 19 ‘types,’ including bottom ashes, fly ashes, calcined clays and slags, as well as less homogenous types such as biomass ashes, glasses and mine tailings. The study more than doubles the number of fly ashes and slags recorded on a database of this kind. The tool then provides a unified assessment of cementitious reactivity and pozzolanicity, also accounting for variables in particle size and amorphous content.

Türkiye: Oyak Cement will convert Mill 3 at its Darıca integrated cement plant to a slag grinding unit, according to local press reports.

The company has submitted the project to the government and the environmental impact assessment process has reportedly begun. The US$252,000 investment will add 14 jobs. The modified facility will grind 1200t/day (360,000t/yr) of slag, along with 18,000t of limestone in its other mills.

UAE: Emsteel has signed a strategic partnership with Finnish company Magsort to produce decarbonised cement using steel slag. The agreement follows an industrial-scale pilot at its Al Ain plant that used 10,000t of steel slag to produce low-carbon cement. To meet growing local demand, Emsteel will build an integrated line at the Al Ain facility to process steel residue from its Abu Dhabi steel plant.

US: Eco Material Technologies has announced the opening of the Blissville Rail Terminal in Queens, New York. The new terminal will enable Eco Material to distribute approximately 50,000t/yr of fly ash from its national network to support local infrastructure projects in the New York metro area. The terminal will utilise rail transportation to deliver fly ash and cementitious materials, which the company says can replace up to 25% of carbon-intensive Portland cement in standard concrete mixes, with Eco Material's technologies reportedly allowing for up to 100% replacement in select applications.

"The opening of the Blissville Terminal is a major step in our efforts to expand access to low-carbon cement alternatives in all major metro areas, " said Grant Quasha, CEO of Eco Material Technologies. "By strengthening our presence in New York, we can better serve future infrastructure projects with innovative materials that reduce reliance on traditional Portland cement and imported steel slag.”

Ireland: Ecocem has secured €4m in research funding as part of the European Innovation Council’s Pathfinder Challenges 2024 in order to optimise electric arc furnace (EAF) slag for low-carbon cement production. The four-year programme is funded by Horizon Europe and will explore ways to enhance EAF slag reactivity and its suitability as a supplementary cementitious material without compromising cement durability. The project was submitted to the Pathfinder Challenge 2 call: “Towards Cement and Concrete as a Carbon Sink.”

Corporate development executive director Eoin Condren said “For many years, we have been pioneering the use of a range of slags and cementitious materials to create scalable and durable low-carbon cement. Thanks to this grant, we will continue our groundbreaking work as the steel industry transitions to new manufacturing processes, delivering a viable solution for a new generation of waste from steel.”

Australia: Boral will receive US$15.4m in government funding for a kiln feed optimisation project at its Berrima Cement Works, with CO₂ emissions expected to reduce by up to 100,000t/yr, based on predicted production rates. The Powering the Regions grant will support the producer’s installation of a new specialised grinding circuit and supporting infrastructure, which will raise the use of alternative raw materials in kiln feed to 23% from 9%, lowering the amount of limestone used.

Boral will use steel manufacturing by-products and industrial waste, including granulated blast furnace slag, steel slag, cement fibre board, fly ash and recycled fine concrete aggregates. The project will be operational in 2028.

The head of innovation and sustainability at Boral, Ali Nezhad, said “In terms of the resulting emissions intensity of the manufactured clinker, the project will result in up to 11% reduction in clinker emission intensity, 9% attributable to a reduction in calcination emissions and 2% attributable to thermal efficiency gains.”

Türkiye: Cement producer Karcimsa Cement said that it will invest US$30m in a 1Mt/yr clinker and granulated slag grinding facility in Kayseri.

The plant will produce ‘green’ cement with low carbon emissions, according to chair of Karcimsa, Soner Ozbey.

Back in March 2024, Türkiye imposed restrictions on cement to expand the use of low-carbon cement in public procurement contracts from 2025.

"The clinker/cement ratio in the cement to be used in public investments will be a maximum of 0.80 as of 2025 and this ratio will decrease to 0.75 by 2030," Karcimsa said.

The company will reportedly procure slag from Kardemir to be used in production.

Karcimsa is a joint venture between Turkish steel firm Kardemir and concrete producer Beycim Beton Sanayi.

UK: The Materials Processing Institute (MPI) is preparing to open its Sustainable Cement and Concrete Centre (SCCC) later in February 2025. The centre will focus on research and material development, including novel formulations for low-carbon cement and concrete and the use of electric arc furnace (EAF) slags in aggregates and clinker production. It will also provide consultancy services to further support clients to accelerate innovation, offering expertise and project management from concept through to pilot stage production.

The SCCC is a part of the EconoMISER programme, led by the Foundation Industries Sustainability Consortium (FISC), which aims to accelerate the decarbonisation of the UK’s so-called foundation industries. These include the cement, metal, glass, ceramic, paper, polymer and chemical sectors. The MPI is based in Middlesborough.

Suvo Strategic Minerals said this week that it had made moves towards establishing a joint-venture between a subsidiary and the Huadi Bantaeng Industry Park (HBIP). The plan is to manufacture and sell low-carbon cement and concrete products that contain nickel slag and other byproducts. This news story is noteworthy because of the location of HBIP in South Sulawesi, Indonesia.

In a release to the Australian Securities Exchange Suvo explained that HBIP is the managing company of the Bantaeng Industrial Park, where ‘significant’ quantities of nickel slag are stockpiled as part of the local nickel pig iron operations. HBIP will supply the nickel slag to the joint-venture. It will also give it access to infrastructure such as land, port facilities and utilities. Suvo subsidiary Climate Tech Cement, for its part, will supply the low carbon cement and or concrete mixtures and/or formulations. This follows the signing of a memorandum of understanding in September 2024, in which the companies agreed to process the nickel slag into geopolymer cement and precast concrete materials.

At first glance Indonesia seems like an unlikely place to market a low-carbon cement or concrete product, given the large cement production overcapacity in the country. The Indonesian Cement Association (ASI) reported a production capacity of just under 120Mt/yr in 2024 and forecast a utilisation rate of 57% in November 2024. However, the government seems serious about reaching net zero by 2060 as the country’s economy develops. The ASI updated its decarbonisation roadmap in 2024 and the draft is currently under review with the Ministry of Industry and consultants from the Bandung Institute of Technology (ITB).

In the latest roadmap, carbon capture is at least a decade away, with the first large-scale capture tentatively anticipated from 2035 onwards. Although Indonesia launched its carbon trading scheme in 2023, it is not expected to start affecting the industrial sector until the late 2020s. Instead, the short-to-medium term Scope 1 reduction methods include increasing the use of alternative fuels, reducing the clinker factor of cement and reducing and/or optimising the specific thermal energy consumption of clinker. Initiatives such as Suvo’s joint-venture in South Sulawesi tie into that middle strand. Separately, over the summer of 2024 the government and producers said that they were working together to introduce and promote the use of Portland composite cement (PCC) and Portland pozzolana cement (PPC). At this time the ASI reckoned that a complete change could cut cement sector emissions by just over a quarter. In June 2024 local media also reported that ASI members were planning to supply low-carbon cement for the Nusantara capital city project to help it realise its aims as a ‘green city.’

Semen Indonesia, the country’s largest producer, reported a clinker factor of 69% in 2023 for all of its cement products, down from 71% in 2021. Limestone was the biggest substitute followed by trass and gypsum. It is currently aiming for a clinker factor of 61% by 2030. In its Sustainability Report for 2023 it said that it was promoting the use of non-OPC (Ordinary Portland Cement) cement “...according to the needs of construction applications.” It added that non-OPC products also had a “...5 - 15% more economical price.” However, the company has not said how its current sales are split between OPC and other products.

One of the surprises at the 26th Technical Symposium & Exhibition of the ASEAN Federation of Cement Manufacturers (AFCM), that took place in Kuala Lumpur in November 2024, was the sheer amount of work that has been going on outside of Europe and North America towards decarbonising building materials. The cement associations of Indonesia, Malaysia and Thailand all presented progress and targets towards this aim at the event. Suvo Strategic Minerals’ joint-venture plans in South Sulawesi are another example of this trend.

Closing points to note about the Suvo project are firstly that it is away from Indonesia’s main cement production area in Java. Secondly, the presumption is that the low-carbon cement and concrete products manufactured by the project will either be cheaper than the competition or benefit from green procurement rules. Finally, nickel slag reserves seem insufficient to reshape the entire national cement market. Yet a general move towards using more supplementary cementitious materials could. Watch this space for more developments.

Read a review of the 26th Technical Symposium & Exhibition of the ASEAN Federation of Cement Manufacturers (AFCM) in the forthcoming January 2024 issue of Global Cement Magazine