Displaying items by tag: recycled concrete paste

France: Holcim France has commissioned its new Saint-Laurent-de-Mûre alternative raw materials plant in Rhône Department. The unit produces cementitious paste from construction and demolition waste using Holcim’s ECOCycle upcycling process. It will source construction and demolition waste from the Lyon Metropolitan Area.

Holcim’s global head of circular construction Vincent Teissier said “Advancing such circular technologies is one of the main pillars of our sustainability strategy. This new advanced crushing unit in Saint-Laurent-de-Mûre is a major step toward using construction and demolition materials to their full value.”

France: Heidelberg Materials has announced plans for its CIRCO₂BETON concrete recycling project. It intends to build an industrial-scale selective separation unit at its Achères quarry near Paris. Here it will recycle demolished concrete by crushing it and separating it into its components: sand, aggregates, and recycled concrete paste (RCP). The recycled sand and aggregates will be reincorporated into new concrete.

The RCP will be transported to the Ranville cement plant in the Normandy region. There, a reactor for enforced carbonation will be installed to carbonate the RCP by exposing it to CO₂-containing exhaust gases from the kiln. The carbonated RCP acts as a carbon sink and will replace clinker in new low-carbon cement types. The project has the potential to reduce the CO₂ emissions of the Ranville cement plant by 20%.

CIRCO₂BETON is supported by the ‘Investment for the Future’ Program coordinated by the Ecological Transition Agency (ADEME). In addition, the Île-de-France region supports the selective separation plant at Achères through its zero-waste and circular economy plan. Subject to the funding, construction of both industrial pilots is scheduled to start in 2024 with production of RCP starting in 2025. The carbonation reactor is planned to be operational by 2026.

Nicola Kimm, the chief sustainability officer at Heidelberg Materials, said ”We are investing in a pioneering large-scale project based on innovative process technologies. Selective separation and CO₂ mineralisation are important levers to reduce the carbon footprint of our products. By closing the materials loop, we prove that concrete has the potential to be the most sustainable building product over its entire life cycle from production to recycling.”

Read more about RCP in the Decemeber 2022 issue of Global Cement Magazine

Holcim launched its formal take on construction and demolition waste (CDW) this week with the unveiling of its ECOCycle technology platform at the BAU architecture fair in Munich. This amounts to managing the distribution, processing, grinding and recycling of CDW back into new building material products. It claims that its concrete, cement and aggregate products can contain 10 - 100% of CDW with no drop in performance.

It is hard to gauge whether this is marketing for existing operations or the start of something new. Yet, in its 2022 Sustainability Report, Holcim said that it recycled 6.8Mt of CDW back into building products and that it is on track to meet its target of 10Mt by 2025. This target was neatly put into words as wanting “to build more new buildings from old ones.” Ahead of the announcement of the launch of ECOCycle, it added that it was going to roll out its Susteno product around Europe. This product, made from 20% CDW, was originally released in Switzerland in the late 2010s. Notably, recent acquisitions by Holcim that connect to its growing focus on CDW include Poland-based Ol-Trans in July 2022, UK-based Wiltshire Heavy Building Materials in October 2022 and UK-based Sivyer Logistics in April 2023.

As covered by Global Cement Weekly in February 2023, Holcim is not the only heavy building materials company pivoting to CDW. The European Union (EU) set a 70% recovery target for it in 2020 and various cement company sustainability reports have described the region as being receptive to moves into this sector. Cemex set up a global waste management subsidiary called Regenera at the end of January 2023. This division covers both alternative fuels, CDW and industrial by-products, so it is more general than Holcim’s current effort, but it shows intent in the same direction. Cemex previously set a target of recycling 14Mt/yr CDW by 2030.

Heidelberg Materials has been working on developing recycled concrete paste and its ReConcrete-360° concrete recycling process. As of its last sustainability report, this process had been tested at the pilot scale and is now being developed and scaled for industrial application. In addition to acquiring UK-based Mick George Group in December 2022 Heidelberg Materials has also purchased Germany-based RWG Holding in January 2023 and Germany-based SER Group in February 2023. All three companies operate in the CDW sector.

The other notable contribution that Heidelberg Materials has been making is as a partner of the ‘Circular City - Building Material Registry for the City of Heidelberg’ project. When Heidelberg Materials announced its involvement in the initiative in mid-2022 it said it was the first city in Europe to apply the principles of urban mining. The goal of the project is to take an inventory of the city’s buildings and then compile it in a digital material registry. The basis for the registry is the Urban Mining Screener developed by EPEA (Environmental Protection Encouragement Agency). This programme can estimate the composition of buildings based on building data such as location, year of construction, building volume or building type. Circular economy supply chains can then act accordingly when a building is retrofitted, demolished or deconstructed. So, for example, at the start of the project it worked out that a former US Army housing estate conversion site was calculated to contain approximately 466,000t of material, with about half in the form of concrete, a fifth in the form of bricks and 5% as metal.

That last example compares to a European Commission estimate that, as a whole, Europe generates around 450 - 500Mt/yr of CDW. A third of this is concrete. As with alternative fuels and slag previously, this may be money going into the ground. Recycling building materials is not new but any significant increase in reusing CDW that can reduce the clinker factor of cement (and the cement factor of concrete) offers a potentially cheaper route to building materials decarbonisation than carbon capture and utilisation/storage at current costs. Hence the continued interest.

UK: Legal & General Capital, an alternative investment arm of financial services company Legal & General, has invested around US$15.5m in Cambridge Electric Cement (CEC) and other companies as part of its strategy to decarbonise the residential sector. It is also investing in Hometree and SunRoof, as well as increasing its existing investment in Sero Technologies.

CEC is developing process to create net zero-CO₂ cement product using recycled concrete paste. It launched a two-year industrial trial of its Cement 2 Zero project in February 2023.

Cemex launched a new waste management division called Regenera this week. Cemex describes Regenera as a “business that provides circularity solutions, including reception, management, recycling, and coprocessing of waste.” The Mexico-based company has a long and leading history with sourcing and using alternative fuels in the cement sector and the new organisation looks set to utilise this experience. What is notable though is how the business is targeting three waste streams: municipal and industrial; industrial by-products; and construction, demolition and excavation waste (CDEW). Bringing the three waste streams together in this way appears to be novel for the heavy building materials sector, particularly the inclusion of CDEW, which we will explore further here.

CDEW is split into fractions, just like the municipal and solid waste streams that end up as alternative fuels at cement plants, but the biggest fractions are generally concrete, followed by bricks. The recycled concrete is then typically used as an aggregate, either in new concrete production or in areas like road construction and earthworks. The use of recycled aggregates (RA) made from CDEW goes back to at least the 1930s in its current form although ‘reusing’ materials from structures such as castles and churches goes back far further. Recycling and reusing CDEW gained a boost in 2020 when the European Union (EU) set a 70% recovery target. However, within the EU the CDEW recycling rates vary considerably and that 2020 target includes the use of CDEW in backfill applications.

In its launch statement for Regenera, Cemex noted that it operates a dock in Paris, where it receives a variety of materials, including construction debris, excavated material and inert soil. These materials are sorted, processed and then transformed into recycled aggregates or organic material used to restore quarries. Cemex then promptly followed up the official launch of Regenera on 30 January 2023 with the acquisition of a majority stake in Shtang Recycle, an Israel-based CDEW recycling company. It added that Shtang Recycle is preparing to build a recycling plant with a production capacity of 0.6Mt/yr of CDEW waste materials. The output from the plant will be used as raw materials for aggregate production.

The focus on CDEW recycling was flagged up at Cemex’s investor event in November 2022. It said that it was targeting a recycling rate of 14Mt/yr of construction and demolition waste by 2030. Other managed waste stream goals included doubling the amount of municipal and industrial waste it manages, to achieve a 50% to fossil fuel substitution rate, and increasing its usage of alternative raw materials and by-products by 30%, thereby eliminating 13Mt/yr of extracted materials.

Cemex is not alone in targeting the CDEW waste sector. Holcim’s recent work in the area goes back to at least 2016 when a recycling unit near its Retznei cement plant in Austria started processing 130,000t/yr of CDEW. It announced in December 2022 that it was setting up a similar recycling centre, also in Austria, at its Mannersdorf cement plant. In October 2022 Holcim acquired Wiltshire Heavy Building Materials in the UK. This company recycles 150,000t/yr of construction and demolition waste into aggregates and concrete. Holcim linked the acquisition to its Strategy 25 target of recycling 10Mt/yr of construction and demolition waste by 2025.

Activity by other cement companies includes the commissioning of a construction waste recycling plant at Gennevilliers in France by CRH-subsidiary Eqiom in April 2022. It was aiming for a target of 50,000t in 2022. In November 2022 Heidelberg Materials agreed to acquire RWG Holding based in Berlin, Germany. Then, in December 2022, it announced a deal to buy Mick George Group in the UK. Both proposed acquisitions are subject to competition authority approval. Heidelberg Materials’ current target is to offer circular alternatives for half of its concrete products by 2030.

The moves by the bigger cement companies into the CDEW sector follow sustainable thinking and the waste hierarchy. Yet the big prize here is to gain a route to dispose of some of their CO₂ emissions through recarbonation and this has been flagged up in several net-zero roadmaps for the cement sector such as those by Cembureau and the Global Cement and Concrete Association (GCCA). Holcim has been involved in the FastCarb project in France, running a pilot at its Val d’Azergues cement plant in 2021. Heidelberg Materials has been testing its own process with so-called recycled concrete paste. The development now appears to be that utilising CDEW has entered the sustainability strategies for some of the big cement-concrete-aggregate producers, targets have been set and acquisitions are happening.

For more information on Heidelberg Materials research into concrete recycling read the January 2023 issue of Global Cement Magazine

UK: Hanson has announced a 'carbon capture breakthrough' in its use of recycled concrete paste (RCP) in the wet scrubber of its Ribblesdale cement plant in Lancashire. In under 30 minutes, 15t of RCP was able to capture 1.5t of CO₂ from the plant's flue emissions. Carbonated RCP is suitable to replace limestone in cement production.

Hanson's sustainability director Marian Garfield said “The trial was carried out with our parent company Heidelberg Materials’ research and development team, and marks another important milestone in our carbon capture journey."