Displaying items by tag: supplementary cementitious materials

Spain: Cementos Portland Valderrivas' Alcalá de Guadaíra plant has secured environmental clearance to use more alternative raw materials and alternative fuels (AF) in its cement production.

The company said "This achievement is a further boost to our sustainable work practices, respecting the environment and contributing to combatting climate change."

North America: A new coalition for the scaling and deployment of low-carbon building materials, the creation of new clean cement and concrete jobs and the promotion of environmental justice launched earlier in January 2024. Called the Decarbonized Cement and Concrete Alliance (DC2), it comprises alternative cement developers Biomason, Brimstone, Chement, Fortera and Terra CO₂, sequestration company Blue Planet Systems, circular concrete producer CarbonBuilt, biogenic limestone producer Minus Materials, hydrothermal processing technology developer Queens Carbon and electrified cement production technology developer Sublime Systems. DC2’s areas of engagement in policy will include tax credits, standards, ecolabeling and subsidisation, in line with the US Department of Energy’s Pathways to Commercial Liftoff: Low-Carbon Cement strategy.

CarbonBuilt’s government and community affairs manager Sal Brzozowski said “DC2’s platform of robust policy, standards and incentives to scale innovative solutions will not only accelerate deep decarbonisation, but also transform the concrete industry from one of the world’s largest CO₂ emitters to one of the world’s largest carbon sinks.”

Switzerland: Swiss cement shipments dropped by 10% year-on-year to 3.7Mt in 2023, from 4.1Mt in 2022. Shipments declined across all quarters, including by 10% quarter-on-quarter in the third quarter. Cement with a reduced clinker factor grew to account for 96% of shipments from 95%, and rail shipments rose to 38%. Ready-mixed concrete plants received 73% of shipments, and building sites 21%.

The Swiss cement association, Cemsuisse, said that it anticipates continued uncertainties and high import pressures in 2024.

Spain: Cementos La Cruz plans to build a new unit to produce reduced-CO₂ cement at its 1.5Mt/yr Abanilla grinding plant in Murcia. In a video posted on YouTube, the producer said that the new unit will produce cement using supplementary cementitious materials (SCMs) derived from industrial waste streams. Additionally, it will source 100% of its electricity consumption from biofuel-fired generators. Cementos La Cruz has secured Euro4.5m in European Union funding for the project.

General director Juan Luis Porrúa said that cement from the upcoming unit will have a specific carbon footprint below 200kg/t, and will eliminate over 400,000t of CO₂ emissions from Spanish construction in its first 10 years of operation.

Sweden: CemVision has announced its first commercial agreement to sell its low carbon cement. Pilot deliveries are scheduled to begin in March 2024 to LKAB. Further commercial agreements are planned over the next four years. CemVision produces its Re-ment product using industrial residual products such as those from the steel and mining sectors instead of limestone.

Anders Lundgren, Chief Sustainability Officer for Business Area Special Products at LKAB, said “The letter of intent include the pilot deliveries and trial use of CemVision’s products in our concrete production, and intent to source from their future full-scale production, which presents a potential to further enhance the circularity and to decarbonise our supply of cement and addressing our emissions in the supply chain.”

Switzerland/UAE: The COP28 UAE Presidency named École Polytechnique Fédérale de Lausanne (EPFL) among its Energy Transition Changemakers in the Heavy Emitting Sectors category. EPFL won the prize for its LC3 limestone calcined clay cement, which replaces 50% of clinker content with calcined kaolinite clay and limestone. LC3 cement reduces CO₂ emissions by 40% compared to ordinary Portland cement (OPC), and is a readily available solution that can be scaled worldwide. EPFL noted the special importance of LC3 cement for CO₂ reduction efforts in developing countries, and sees it as having the potential to eliminate 500Mt/yr of global CO₂ emissions by 2030. In a post to LinkedIn, the LC3 Project said that nine plants around the world currently produce LC3 cement, with a further 20 planned before 2025.

India: Adani Group says that it will power 60% of its cement production using renewable energy by 2028. In a post on X, the group noted that its Adani Cement business uses fly ash or slag in cement production at 90% of its plants.

US: Terra CO₂ has entered into an exclusive agreement with Eagle Materials, under which the cement producer will set up plants to produce Terra CO₂’s supplementary cementitious materials (SCM) in three cities, including Greater Denver in Colorado. Terra CO2's SCM consists of ground, heated glass spheres made from silicate-containing igneous rocks and sediments, which can be used in cement production to lower CO₂ emissions by 70% compared to ordinary Portland cement (OPC).

Terra CO₂'s chief executive officer Bill Yearsley said “New climate tech needs to be deployed quickly to meet 2030 and 2050 climate goals. Terra is working hard to accelerate the deployment of its commercial plants through strategic partnerships, deploying more capital and shortening timelines. We are thrilled to work with a partner like Eagle Materials to build commercial plants for sustainable construction, and act on this urgency through our shared commitment to action. In the absence of a 'climate tech express lane' from the government, working with industry leaders is key to innovating and expediting low-carbon solutions for the industry."

Taiwan: Asia Cement Corporation tested its waste wind turbine blade processing capacities using 12t of blades earlier in November 2023. The cement producer had previously processed 9t of waste turbine blades for use in its plants up to the end of October 2023. Asia Cement Corporation says that the waste consists of fibre-reinforced plastic (FRP), which is 60% silicon dioxide, calcium oxide and aluminium oxide and 40% polyester. The polyester can replace fossil fuels as alternative fuel (AF) for cement plants, while the other chemical compounds can serve as supplementary cementitious materials (SCMs).

Last week the US General Services Administration (GSA) announced that it was investing US$2bn on over 150 construction projects that use low-embodied carbon (LEC) materials. The funding is intended to support the use of US-manufactured low carbon asphalt, concrete, glass and steel as part of the Inflation Reduction Act. For readers who don’t know, the GSA manages federal government property and provides contracting options for government agencies. As part of this new message, it will spend US$767m on LEC concrete on federal government buildings projects following a pilot that started in May 2023. The full list of the projects can be found here.

This is relevant because the US-based ready-mixed concrete (RMX) market has been valued roughly at around US$60bn/yr. One estimate of how much the US federal government spent on concrete was around US$5bn in 2018. So the government buys a significant minority of RMX in the country, and if it starts specifying LEC products, this will affect the industry. And, at present at least, a key ingredient of all that concrete is cement.

This isn’t the first time that legislators in the US have specified LEC concrete. In 2019 Marin County in California introduced what it said was the world’s first building code that attempted to minimise carbon emissions from concrete production. It did this by setting maximum ordinary Portland cement (OPC) and embodied carbon levels and offering several ways suppliers can achieve this, including increasing the use of supplementary cementitious materials (SCM), using admixtures, optimising concrete mixtures and so on. Unlike the GSA’s approach in November 2023 though, this applies to all plain and reinforced concrete installed in the area, not just a portion of procured concrete via a government agency. Other similar regional schemes in the US include limits on embodied carbon levels in RMX in Denver, Colorado, and a reduction in the cement used in RMX in Berkeley, California. Environmental services company Tangible compiled a wider list of embodied carbon building codes in North America that can be viewed here. This grouping also includes the use of building intensity policies, whole building life cycle assessments (LCA), environmental product declarations (EPD), demolition and deconstruction directives, tax incentives and building reuse plans.

Government-backed procurement codes promoting or requiring the use of LEC building materials for infrastructure projects have been around for a while in various places. The general trend has been to start with measurement via tools such as LCAs and EPDs, move on to government procurement and then start setting embodied carbon limits for buildings. In the US the GSA’s latest pronouncement follows on from the Federal Buy Clean Initiative and from when California introduced its Buy Clean California Act in 2017. Outside of the US similar programmes have been introduced in countries including Canada, Germany, the Netherlands, Sweden and the UK. On the corporate side members of the World Economic Forum’s First Movers’ Coalition have committed to purchasing or specifying volumes of LEC cement and/or concrete by 2030. Examples of whole countries actually setting embodied carbon emissions limits for non-government buildings are rarer, but some are emerging. Both France and Sweden, for example, introduced laws in 2022 that start by analysing life-cycle emissions of buildings and will move on to setting embodied carbon limits in the late 2020s. Denmark, Finland and New Zealand are also in the process of introducing similar schemes. The next big move could be in the EU, where legislators are considering embodied carbon limits for building materials as part of its ongoing revisions to its Energy Performance of Buildings Directive or the Construction Products Regulation legislations. Lobbying, debate and arguing remains ongoing at present.

To finish, Ireland-based Ecocem spent a period in the 2010s attempting to build a slag cement grinding plant at Vallejo, Solano County, in the San Francisco Bay Area of California. The project met with considerable local opposition on environmental grounds and was eventually refused planning permission. The irony is that slag cement is one of those SCM-style cements that Marin County, also in the San Francisco Bay Area, started encouraging the use of just a few years later. Ecocem held its inaugural science symposium in Paris this week. A number of scientists who attended the event called for existing low carbon technologies to be adopted by the cement and concrete sectors as fast as possible. One such approach is to lower the clinker factor in cement through the use of products that Ecocem and other companies sell. A point to consider is, if Marin County’s code or the GSA’s recent procurement directive came earlier, then that slag plant in Vallejo might have been built. Encouraging the use of LEC building materials by governments looks set to proliferate but it may not be a straightforward process. Clear and consistent policies will be key.