Heidelberg Materials announced a US acquisition at the same time as the ongoing IEEE/IAS-PCA Cement Conference in Dallas, Texas this week. It has entered into a purchase agreement to acquire The SEFA Group, a fly ash recycling company based in Lexington, South Carolina. Its operations include five beneficiation plants, five utility partners, 20 locations and over 500 employees. It supplies fly ash to over 800 ready-mixed concrete plants in 13 states. It processes around 1Mt/yr of ash from storage ponds using its proprietary thermal beneficiation process. No value for the acquisition was disclosed.
The proposition for a heavy building materials manufacturer of securing a supply of fly ash is an attractive one. Fly ash can improve the performance of concrete, reduce its cost by lowering the amount of ordinary Portland cement (OPC) required and decrease the associated carbon footprint. It can also be use to make blended cement products. Heidelberg Materials and its US-subsidiary Lehigh Hanson could have various options here including using this new supply of fly ash internally, selling it on to other companies or licensing the beneficiation technology. Heidelberg Materials’ global sustainability report in 2021 reported that just under 9% of its cement-type portfolio comprised pozzolana or fly ash cements.
Graph 1: Coal combustion product production and use, 1991 – 2021. Source: ACAA.
Data from the American Coal Ash Association (ACAA) shows in Graph 1 that coal combustion products (CCP) production have declined in the last decade as the proportion used has steadily risen. In its annual production and use survey, the ACAA revealed that the use of harvested ash continued to grow in 2021 and that it constituted around 10% of the volume of ash recycled from current power plant operation. Thomas H Adams, the executive director of the ACAA, said “The rapidly increasing utilisation of harvested CCP shows that beneficial use markets are adapting to the decline in coal-fuelled electricity generation in the US. New logistics and technology strategies are being deployed to ensure these valuable resources remain available for safe and productive use.” Separately, the ACAA reported that coal-fuelled power stations represented about 50% of the country’s electricity demand in the mid-2010s compared to 20 – 25% in 2021 despite base-load remaining the same. It forecast that fly ash production was likely to remain fairly constant to around 2040 but that harvesting would help to cut the gap between supply and demand in some regional markets. It said that over 2Bnt of coal ash was in disposal. However, no indication of how recoverable this was given although it did note the higher cost of beneficiation. Work on updating specifications was ongoing to suit current circumstances.
As with the slag market, this presents a dilemma for cement and concrete producers that want to become more sustainable. They want to use more by-products from other carbon-intensive heavy industries – such as coal-fired power stations and steel plants – but these industries themselves are also trying to become more sustainable and are producing less secondary cementitious materials. Heidelberg Materials’ interest in a fly ash beneficiation company makes sense because it secures a bigger portion of a dwindling resource from the direct operations and opens up the possibility of selling the beneficiation technology to others. It is also worth mentioning that other fly ash thermal beneficiation processes are available. For example, Charah Solutions installed its MP618 technology at its Sulphur terminal in Louisiana in early 2019.
The general fly ash market in the US looks set to track the level of coal-fired power generation for the foreseeable future. Yet the proportion of CCPs being used continues to rise. In this context focusing on harvesting may be starting to make more financial sense. Charah Solutions’s new unit in 2019 and SEFA Group’s new units in 2020 and 2021 seem to support this view. Heidelberg Materials’ acquisition of SEFA Group may be further confirmation of this.