Displaying items by tag: supplementary cementitious materials

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.

US: Sustainable technology developer ClimeCo has welcomed the Climate Action Reserve (CAR)’s launch of the US Low-Carbon Cement Protocol. The protocol will provide guidance on quantifying, monitoring, reporting and verifying emissions reductions associated with the use of supplementary cementitious materials (SCMs) in alternative cement production. ClimeCo says that this will help to establish the eligibility of various waste streams and naturally occurring materials for use in cement.

ClimeCo president and CEO Bill Flederbach said "While demand for cement has never been higher, it remains an exceptionally difficult-to-abate industry. This new protocol demonstrates the power of credible, validated and science-based voluntary carbon credits in accelerating the pace and adoption of environmental reforms. It also confirms ClimeCo's belief that, by engaging the right partners and taking a holistic approach, every industry and every company, even those facing the biggest challenges, can make a huge difference. Time is of the essence, and ClimeCo is proud to lead the way toward a brighter future."

India: SRMPR Cements has launched its Portland pozzolana cement (PPC) for the first time, in Tamil Nadu. The Hindu BusinessLine newspaper has reported that the company controls 420,000t/yr of cement production capacity across three facilities in Tamil Nadu and neighbouring Andhra Pradesh. It invested a total US$27m in its production facilities and warehouses. SRMPR Cements will sell its PPC in 50kg bags. It also plans to launch ordinary Portland cement (OPC) in the future. It said that its products will help to meet ‘massive’ demand from public construction projects.

CEO Ohm Prakash said that the producer has already concluded deals with 100 different regional retailers of cement.

Vietnam: Cement producers received 811,000t of boiler slag and fly ash from the Vinh Tan 1 coal-fired power plant in Binh Thuan during the first nine months of 2023. This corresponds to 74% of the volume of the by-products generated at the plant during the period. Việt Nam News has reported that the nearby Vinh Tan 4 coal-fired power plant also ‘almost entirely’ avoided waste in the same way. The Vinh Tan 1 coal-fired power plant ended the period with 4.3Mt of ash and slag in stockpiles, while the neighbouring Vinh Tan 2 Thermal Power Plant had 7Mt.

The provincial government of Binh Thuan Province has lobbied the Ministry of Construction to review and adjust current requirements around HDPE liner use, water quality testing and radiation safety in order to facilitate the use of boiler slag and fly ash in cement and other construction products.

Ghana: CIMPOR has appointed Germany-based ThyssenKrupp Polysius to build a 1280t/day flash activator for clay. The activator will supply calcined clay for use in the production of cement with a clinker factor as low as 50%. This can reduce the cement’s CO₂ emissions by 40% compared with ordinary Portland cement (OPC). The supplier’s contract covers engineering, supply of core equipment and supervision of the project. The equipment includes parts for clay handling, a hammer mill, a flash dryer and preheating and cooling equipment, as well as storage silos. The activator will be natural gas-fired.

Polysius Activated Clay product owner Leo Fit said "Our technology is not only more environmentally friendly, but also creates cost benefits for our customers like CIMPOR. In many regions, limestone is scarce and clinker has to be imported at high cost. At the same time, suitable clay sources are available. The increasing pressure to reduce greenhouse gas emissions is leading cement manufacturers to rethink. They need an alternative that is cost-efficient and at the same time provides high-quality cement. This is exactly what Polysius activated clay offers."

West Africa: Ciments de l'Afrique (CIMAF) plans to produce limestone calcined clay cement (LC3) at cement plants in West Africa. Parent company Omnium des Industries et de la Promotion (OIP) plans to build a calcined clay production facility in Burkina Faso to supply the material. Gulf Oil & Gas News has reported that OIP secured a Euro45m loan from World Bank Group’s International Finance Corporation on 10 October 2023. It will invest Euro32.4m in construction of its upcoming calcined clay production facility and Euro12.6m in
construction of solar power plants for three CIMAF subsidiaries in Burkina Faso, Chad and Mali.

CIMAF CEO Anas Sefrioui said "IFC's green loan provides essential long-term financing for our projects in Africa. Through the green loan structure, we are bringing the best practices in financing decarbonisation initiatives in the region. We look forward to reducing our carbon footprint and replicating these best practices in our African operations.”

EU/UK: EUROSLAG says that the use of ground granulated blast furnace slag (GGBFS) in cement production in the EU and UK between 2000 and 2022 has generated a cumulative reduction in CO₂ emissions of 408Mt. GGBFS replaced 716Mt-worth of raw materials over the period.

EUROSLAG Chair Thomas Reiche said "Resource conservation through secondary raw materials, especially in the construction sector, and lower emissions of climate-damaging CO₂, are of outstanding ecological and economic importance. The use of ferrous slags makes an important contribution to this. EUROSLAG is working multilaterally to master the enormous challenges in the coming years, above all the transformation of the steel industry, through research and adjustments to national and European regulations.”

US: Terra CO₂ plans to build its first commercial-scale supplementary cementitious materials (SCM) plant in Texas. The plant will have a production capacity of 240,000t/yr. Asher Materials secured an exclusive market license to operate the plant. Terra CO₂’s SCM can replace up to 40% of cement content in concrete. Asher Materials will produce the materials from silicate rock from existing local aggregates operations.

Terra CO₂ chief science officer DJ Lake said "From start to finish, we've designed a system to create large-scale impact in the real world. Our game-changing production process converts affordable, abundant and local raw materials to cementitious material that meets rigorous performance standards.” Lake continued “True sustainability will come from deep innovations in materials and technology and not from incremental improvements to the existing cement supply chain."