Cement Recycling: Paving the Way for a Circular Economy in Construction

As cities rise and skylines stretch ever higher, the world’s hunger for cement – the backbone of modern infrastructure – is set to soar. By 2030, the demand for this critical building material is expected to surge, fueled by the rapid pace of urbanisation and the construction boom in emerging economies.

In 2022, global cement manufacturing produced 1.6 billion metric tonnes of CO2, accounting for about 8 per cent of the world's total emissions. What’s more, estimates suggest that cement production could grow by up to 23 per cent over the next two decades.

Builders rely on cement as a key component of concrete, which is the second most widely used material after water. With global concrete production expected to grow from 14 to 20 billion cubic metres by mid-century, rising urbanisation and infrastructure demand could drive CO2 emissions from the sector to 3.8 billion tonnes annually. These figures highlight the significant impact that building materials have on the global carbon footprint.

One of the most effective ways to meet production demands is through cement recycling. Reusing and recycling cement not only saves on raw materials but also reuses materials that would otherwise end up in landfills. This shift supports the construction industry's transition toward a circular economy, which offers both environmental and economic benefits.

A circular construction economy

In the traditional "take, make, dispose" model, resources are extracted, used, and discarded as waste.

For instance, carbon prices in the European Union are projected to nearly reach €100 per tonne of CO2 – a level that could become standard by 2030. Additionally, landfill costs for construction and demolition waste (CDW) will likely continue affecting the entire building industry, with prices potentially hitting €150 per tonne. Considering global average prices for CO2 and landfills, these costs could total around €210 billion by 2050.

However, a variety of forces are making the construction industry shift toward a more circular economy - one that focuses on sustainability and resource efficiency.

Cement recycling involves creating closed-loop systems in which materials like recycled concrete are consistently reused and repurposed, extending their lifespan. With over 35 per cent of construction waste ending up in landfills annually, this circular economy approach offers a powerful alternative to the traditional model by promoting sustainable reuse.

A telling example of this shift is Regenera, a company that specialises in repurposing construction, demolition, and excavation waste to create value-added products. One of the company’s key projects is transforming old concrete into smaller pieces, such as crushed stone and gravel, which can then be reused in new construction. These materials are ideal for applications like base layers for roads or even mixed into fresh concrete, reducing the need for new raw materials and minimising waste. By turning what would have been waste into valuable materials, Regenera is not only reducing landfill use but also helping to conserve natural resources.

Recycling also provides financial benefits. For example, Pennsylvania's Department of Transportation (PennDOT) has shown how concrete recycling can lead to substantial financial savings. By reusing recycled concrete in road construction projects, PennDOT achieved cost reductions of up to 27 percent. These savings stem from lowering the need for new raw materials and cutting transportation expenses, making the process not only environmentally sustainable but also economically beneficial for the state.

Implementation challenges

One major challenge to implementing and scaling cement recycling efforts lies in the decentralised nature of the construction industry. Construction involves a wide array of stakeholders, including governments, suppliers, and local contractors, which means that achieving a circular economy requires widespread collaboration. While these stakeholders are gradually becoming more aligned on the advantages of cement recycling, fragmented supply chains and varying regulations across regions complicate these efforts.

In my eight years of experience in construction and implementing sustainable cement recycling programs, I’ve observed that despite progress in stricter regulations and the increased adoption of circular practices, the transition remains slow in the absence of a coordinated industry-wide approach. Although some businesses are embracing these changes, scaling cement recycling to an industry-wide level will require a unified commitment.

One of the most significant challenges businesses face is the substantial initial investment required for implementing recycling technologies, including infrastructure and training, which has often led to pushback. However, my message to these companies is simple: these initial expenses are dropping quickly as innovative technologies continue to emerge, and government incentives for sustainable practices increase. This combination is making it easier for companies to adopt recycling processes and realise long-term savings, both environmentally and financially.

Moving forward

In the long term, the return on investment for these efforts will far outweigh the initial cost. Businesses that invest now not only benefit from the lower material and disposal costs that come with a circular economy, but they will also position themselves as leaders in sustainability. This competitive edge can lead to securing more contracts, especially as clients and governments increasingly prioritise eco-friendly practices. In my view, cement recycling is more than just a trend; it's a fundamental shift in the way the industry operates.

Ibon Iribar is Investment and Open Innovation Advisor at Cemex Ventures.