Low-carbon concrete
Shrinking the construction industry’s CO2 footprint with low-carbon minerals
Concrete demonstrates unparalleled strength, durability, versatility, fire resistance and can be easily sourced, making it the most widespread material used in modern constructions - concrete consumption is twice that of wood, steel, plastic and aluminum combined. However, with concrete production currently accounting for around 8% of the planet’s CO2 emissions, the race is on to find ways to reduce its carbon footprint.
We are partnering with construction companies to support the sector in its search for viable solutions for mitigating the carbon footprint of concrete. Our solutions include a portfolio of metakaolin, calcium-carbonate and perlite mineral solutions which are excellent candidates for the partial replacement of Portland cement, whilst conferring a host of benefits to the end product.
Population growth and escalating urbanization are driving demand for new buildings and infrastructure. By 2050, more than two-thirds of the world's population will be living in cities and towns, putting immense pressure on the planet's natural resources. In parallel, climate change is spurring us to take action to significantly reduce our greenhouse gas (GHG) emissions and to make a major shift towards a low-carbon economy.
With the building and construction industry representing around 37% of global CO₂ emissions1, it is among the sectors with the biggest impact on global climate change. Today, the focus is more than ever on embodied carbon in construction, - ie. the emissions associated with materials / construction processes throughout the lifecycle of a building or infrastructure - and demand for low-carbon building materials is on the rise.
Concrete production is a big contributor to the embodied carbon in any building project; so low-carbon concrete will play a key role in helping the sector on its way to its 2050 decarbonization target.
1 - In 2021 - UN Environment 2022 Global Status Report for Buildings and Construction
Low-carbon concrete is generally produced by replacing traditional cement content, such as Ordinary Portland Cement (OPC) which has a high carbon footprint, with a combination of various cementitious minerals and hydraulic binders which have a much lower CO₂ footprint.
Low-carbon concrete generally demonstrates similar - or even superior properties - to Portland cement-based concrete.
Due to its pozzolanic properties, metakaolin acts as a good binder in concrete, while conferring a host of other benefits such as excellent compressive strength, improved durability due to lower porosity and reduced efflorescence. This makes it an ideal candidate for the partial replacement of Portland cement in concrete formulations. Metakaolin has a carbon footprint up to around four times lower than Ordinary Portland Cement (OPC), whilst providing equivalent or even superior performance.
We offer a range of metakaolins for low-carbon cements - including our well-known Argical® M produced at our Clérac facility in France, and our Metastar® North American grades from Sandersville, USA.
Calcium carbonate is an excellent cost-effective cementitious material for concrete production where it improves compactness and workability. It is a key component in the production of a new type of low-carbon binder called LC3 (Limestone Calcined Clay Cement) which combines OPC, metakaolin and calcium carbonate. Calcium carbonate has a carbon footprint at least 15 times lower than OPC.
Calcium carbonates for low-carbon concrete are produced at our French Villers operation, and North American Sylacauga operation. They include our PolCarb™, ImerCarb™ and ImerFill™ grades.
We can also offer a wide range of perlite products that have been proved, when processed, to act as a successful partial replacement for portland cement.
We are committed to supporting the construction sector’s ambition to achieve its sustainability ambitions through a growing portfolio of market-driven solutions which foster innovation and sustainability.
In addition to our range of low-carbon cement materials for concrete production, our portfolio includes solutions to serve a broad array of construction markets, including paints and coatings, adhesives, caulks and sealants - among other building materials. These solutions improve the long-term performance, properties and aesthetics of the end product, as well as thermal insulation, and even fire safety.
Our new LEAP calcium aluminate speciality binder for lean-mix mortars reduces the CO2 footprint of clinker technologies.
In recent years, we have rolled out an ambitious program to screen our portfolio with regard to environmental and social criteria. This science-based method, which is aligned with international standards, enables us to measure the impact and benefits of our products. The highest performers are awarded our Pioneer certification.
We have also embarked on our own sustainability journey to reduce our GHG emissions by 42%, in absolute value, by the year 2030.
Imerys has just completed the acquisition of Société de Traitement Industriel des Minéraux (STIM), a French family business based in Monteux, near Avignon. STIM is a historic partner of about 20 years.
A project to test calcined clay as an ingredient in low-carbon concrete has proven its sustainable potential to reduce the cement sector's environmental impact from its current level of 8% of global CO₂ emissions.
As urbanization in India accelerates, so does the country’s construction sector and demand for locally-produced, sustainable construction practices suited to the subcontinent. Inaugurated one year ago, Imerys’ state-of-the-art calcium aluminate plant in Vizag, Andhra Pradesh, in India’s southeastern coastal region, produces new products that answer this precise need. It recently showcased its products and initiatives during a construction workshop for customers on October 16 in Mumbai.
While a building’s structure might make it a house, a building’s insulation will make it a home. And, while a builder might have many insulation options to choose from, only one can claim to be totally safe: mineral foams.
