Ecocem announced this week that it has achieved certification in the US for its ACT low-carbon cement technology. This follows CRH’s agreement to buy US-based Eco Material Technologies, a supplier of supplementary cementitious materials (SCM), which was revealed in late July 2025. These moves and others mark a flurry of activity by various companies in the US SCM sector in recent months.
Donal O’Riain, the founder and managing director of Ireland-based Ecocem, underlined the importance of certification in North America when he said that “The US is one of the largest cement markets in the world, and this certification will support integration into existing supply chains and offers a pathway for the sector to rapidly decarbonise.” The country imported just under a fifth, 19Mt, of its Portland and blended cement in 2024 according to the United States Geological Survey (USGS).
Ecocem started out as a manufacturer of cements made using ground granulated blast furnace slag (GGBS), a SCM, in the early 2000s. Its ACT technology was formally announced in 2022. It is described as a process that can make cements using “available fillers like limestone and local SCMs.” It is currently scheduled for a commercial launch in 2026, starting in France. In the US it is planning to build a terminal and mill at the Port of Los Angeles in California. This follows a previous attempt to build a slag grinding plant, also in California, in the 2010s.
CRH, another cement company with strong links to Ireland incidentally, said on 29 July 2025 that it had agreed to acquire Eco Material for US$2.1bn. The latter operates a network of fly ash, pozzolan, synthetic gypsum and green cement operations. It partners with electricity generators to process about 7Mt/yr of fly ash and 3Mt/yr of synthetic gypsum and other materials. As CRH’s CEO Jim Mintern put it, “this transaction secures the long-term supply of critical materials for future growth and puts CRH at the forefront of the transition to next generation cement and concrete.” The deal is expected to close by the end of 2025. In separate comments to analysts Mintern added that he expects the market for SCMs to double in the US by 2050.
Other players have also been busy in recent months. Amrize, for example, noted in its financial results for the second quarter of 2025 that it had broken ground on a new fly ash beneficiation facility in Virginia in the reporting period. Last week, Graymont and Fortera signed an agreement to produce Fortera’s ReAct low-carbon cement product by using Graymont’s existing lime production operations. Fortera runs a plant in Redding, California that takes captured CO2 from the adjacent CalPortland cement plant and uses it to manufacture its own proprietary SCM. Back in April 2025 Buzzi Unicem said that it had partnered with Queens Carbon to produce a novel cement and SCM. The start-up was intending to build a 2000t/yr demonstration plant at Buzzi Unicem’s cement plant in Stockertown, Pennsylvania.
The backdrop to all of this attention on SCMs in the US are the cost of cement and sustainability. Using more SCMs reduces clinker usage in cement and it can reduce the cost. At the same time reducing the amount of clinker used decreases the amount of CO2 emissions. So, for example, Ecocem says that its ACT technology can reduce CO2 emissions by up to 70% compared to conventional cement.
A report by Mckinsey on SCMs in the autumn of 2024 reckoned that growth in the cement market in North America was expected to be ‘robust’ in the next 15 years to 2050. However, the sector faces material, particularly clinker, and labour shortages. Enter SCMs! It went on to assert that much of the available stocks of GGBS and fly ash in the country are effectively used. Yet, traditional industrial SCMs such as GGBS, fly ash and limestone are anticipated to be available for longer than in Europe as industries such as steel manufacture and electricity generation will take longer to decarbonise. Hence companies such as Ecocem are preparing to import them, ones like CRH are cornering existing stocks and others such as Fortera and Queens Carbon are working on creating their own ‘virgin’ sources. At the same time the American Cement Association has been promoting the use of Portland Limestone Cement in the country.
All this helps to explain the interest in SCMs in the US right now. It’s a busy moment.
