Global Slag News

UK: Contractors poured 736m³ of cement-free concrete in an 11-hour continuous pour at the Hurst substation tunnel drive shaft of the London Power Tunnels project on 11 May 2023. Construction Index News has reported that Capital Concrete supplied the concrete. It uses a formula developed by Earth Friendly Concrete to replace 100% of cement with fly ash and ground granulated blast furnace slag (GGBFS) in the presence of an activator and admix solution. The supplier said that the concrete will reduce CO₂ emissions by 64% compared with ordinary Portland cement (OPC), corresponding to 111kg/m³ of concrete.

France: Hoffmann Green Cement Technologies has commissioned its H2 plant, a 1000t/day clinker-free cement plant, adjacent to its existing H1 clinker-free cement plant in Bournezeau, Pays de la Loire. L'Usine Nouvelle News has reported that the new plant took 24 months to build and cost Euro22m. The main part of the plant consists of a 70m tower, where activated clay, ground granulated blast furnace slag (GGBFS) and gypsum are mixed to produce the cement. It is installed with solar panels capable of supplying 50% of its energy consumption. The producer says that its clinker-free cement has over 90% lower CO2 emissions than cement produced with ordinary Portland cement (OPC). It aims to sell 24,000t of the product throughout 2023.

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.

US: The Slag Cement Association (SCA) has announced the winners of its 2022 Slag Cement in Sustainable Concrete Awards program at the ACI Concrete Convention that took place in San Francisco in early April 2023.

Eighteen construction projects from across the US were chosen to showcase the broad applications of slag cement. These construction projects were awarded in six categories: infrastructure, high performance, architectural, durability, innovative applications, and lower carbon concrete. Two research projects on slag cement use were also recognised in the program. The slag cement and concrete suppliers included Argos, Heidelberg Materials, Holcim, Ozinga, Skyway Cement and St Marys Cement.

Finland: VTT Technical Research Centre subsidiary Carbonaide has concluded its seed funding round, having raised funds worth Euro1.8m. Lakan Betoni, which produces precast and ready-mix concrete, led the funding, along with utilities provider Vantaa Energy. Carbonaide will use the funds to build an industrial pilot plant for its carbon neutral precast concrete product at an existing precast concrete plant in Hollola. The plant will bind captured CO₂ in the product at atmospheric pressure. The process generates 50% lower CO₂ emissions than precast concrete production using ordinary Portland cement (OPC). Suitable raw materials include ground granulated blast furnace slag (GGBFS), green liquor dregs and bio-ash. In trial production, the use of GGBFS gave Carbonaide's concrete a negative carbon footprint of -60kg/m³.

Other sources of loans and in-kind contributions included Finnish state innovation fund Business Finland.