Global Slag News

France: The Scientific and Technical Center for Building (CSTB) has certified Hoffmann Green Cement Technologies’ clinkerless H-UKR alkali-activated slag cement for structural use in buildings of all types. BusinessWire News has reported that the certification confirms the product’s safety, sustainability, lifespan and performance in conformity with Eurocode 2 and Eurocode 8 design standards.

Co-founders Julien Blanchard and David Hoffmann said “In the midst of ongoing frenetic communication regarding carbon neutrality, Hoffmann Green Cement is as usual endeavouring to back its announcements with verified and evaluated elements. The granting of these evaluations further objectifies the quality of our cement, notably with the awarding of a lifespan of 100 years. In this regard, we would like to thank the CSTB’s teams for drafting this unprecedented technical appraisal and our own teams who are working tirelessly on seeking innovative decarbonised solutions to preserve tomorrow’s world.”

Poland: The Building Research Institute has issued environmental product declarations (EPDs) for Cemex Poland’s CEM III slag cement and five other cements produced at its Chełm and Rudniki cement plants and Gdynia grinding plant. The company additionally obtained EPD certification for its Vertua Classic and Vertua Plus concrete products, which contain cement produced using supplementary cementitious materials (SCMs).

Materials director Michał Grys said “For us, product certification is another important step towards sustainable construction and a sustainable future. EPD declarations provide our clients with additional confirmation of the properties of products offered by Cemex Poland. They also improve their chances of obtaining LEED or BREEAM certificates for their investments.”

US: Harsco’s Environmental division has driven its parent group’s revenue in 2021 as services and product demand increased. Its revenue rose by 17% year-on-year to US$1.07bn in 2021 from US$914m in 2020. Its operating income grew by 75% to US$103m from US$59m. Overall group revenue and operating income increased by 20% to US$1.85bn and from a loss of US$3.3m in 2020 to a profit of US$88.4m respectively.

“For the fourth quarter, our businesses continued to benefit from increased environmental solutions demand, and I'm pleased to have met our expectations for the quarter. However, steel volumes slowed through the fourth quarter in some markets, inflation pressures persisted, and labour-market tightness and Omicron impacted productivity. We were able to offset these pressures by controlling our overall spending in the fourth quarter,” said chairman and chief executive officer Nick Grasberger. He added that the group expects to see further improved operating results from its Environmental division in 2022.

UK: Tarmac has demonstrated a new concrete product using a high proportion of slag with Align, the joint venture building part of HS2, a new high-speed railway line. It demonstrated the potential to use very high ground granulated blast furnace slag (GGBS) content in excess of 90%, as an alkali activated cementitious material conforming to BS EN197, the standard for cementitious materials allowed to be used in ready mixed concrete, to significantly reduce carbon emissions, whilst still producing a quality finish and allowing normal construction and demoulding times.

Demonstration and testing at full scale used one of three Tarmac concrete batch plants at a Chalfont Lane construction site in Hertfordshire. A structural slab forming part of the new viaduct pre-cast factory and a vertical wall were poured. Tarmac says that the mixes, designed to Align concrete specification, exceeded expectations in both fresh and hardened properties, and showed that the new concrete can be produced in normal concrete plants and placed via mixer truck and by skip with a tremie pipe. The new low carbon concrete has a carbon footprint following industry BSI PAS2050 calculation rules that gives a 62% reduction in CO₂e per cubic metre of concrete, compared to a standard CEM I concrete, meeting the same specification in the same raw materials. The footprint covers all aspects of the concrete production and supply with no carbon off-setting applied, delivering an actual footprint of 133kg/m³ CO₂e. This represents a saving of 220t CO₂e for every 1000m³ produced.

“Together we’ve shown this new concrete is fit for purpose in slabs and walls, with good repeatability and works with standard production and construction methods. This product is a great step along the industry zero carbon routemap, and the demonstration will help accelerate adoption of this new concrete,” said Robert Gossling, head of commercial engineering solutions at Tarmac.

Tarmac is supplying concrete for the construction of the Central 1 section of HS2 Phase One that is being built by Align. This includes a 22km section of high-speed rail infrastructure incorporating a 3km viaduct across the Colne Valley, a 16km twin-bored tunnel, and five vent shafts handling both intervention and tunnel ventilation facilities.

Austria: Neuson Hydrotec is promoting its MRP40300 type mobile screener and crusher. The tracked product was developed to screen waste slag-containing material on site using magnetic separators and then crush it for reuse. The unit consists of: a vibrating feed and dosing unit, for converting discontinuous feed into continuous feeding of the bulk material into the plant; a vibration sieve for separation into up to four fractions; up to three magnetic separators for separating bulk materials; and discharge belts for the continuous discharge of the individual fractions.

“With the MRP, we were able to create the missing link between breaking steel slag and the finished, sorted end product. It was important to us not only to crush the steel-containing slag with our patented jaw crusher, but also to be able to subsequently separate the iron-containing material and slag into different fractions. Our customers can now look after several company locations with our mobile machines. The construction of stationary systems at each location is no longer absolutely necessary,” said Markus Zweimüller, head of the business machines division at Neuson Hydrotec.

Linz-based Neuson Hydrotec is a manufacturer of hydraulic and drive technology products for mobile and stationary applications.