The construction industry faces the challenge of lessening the environmental impact of its materials, specifically cement. According to researchers and scientists, cement is responsible for approximately 7% of global carbon emissions. While it may seem like a small percentage, consider how many materials contribute to global emissions.

A team of researchers from the University of East London (UEL) uncovered a novel solution that could turn a natural, common waste into a low-carbon ingredient for concrete. Their solution lies within seashells.

Their research focuses specifically on discarded scallop shells. Researchers ground the shells into fine powders and substituted the material for a portion of the cement mix. They successfully reduced carbon by 36%. Additionally, the team preserved a majority of the concrete’s essential performance features.

The question remains: Can it be a viable option for sustainable construction?

Discarded Seashells Could Cut Concrete’s Carbon Footprint

Dr. Ali Abass, Associate Professor of Structural Engineering at UEL and the study’s lead, highlighted the practical implications of the discovery, particularly its potential for scaling.

“Concrete is everywhere, and consequently its carbon footprint is enormous,” Dr. Abass said. “What we’ve shown is that something as ordinary as discarded shells can make a meaningful dent in those emissions.”

He added, “At moderate replacement levels the concrete behaves very well, which means this could be scaled up in real-world settings.”

Through detailed analysis, the researchers uncovered the scientific basis behind its performance benefits. Once the calcium-rich shells are processed, they help refine the concrete’s pore structure, supporting the formation of binding compounds. The function acts as a filler and partial cement substitute, positioning the material as a viable replacement.

As carbon reporting becomes more prevalent, the pressure to decarbonize the industry rises. This new research, and possible development of a low-carbon concrete, points toward a practical circular economic model, where natural waste is transformed into building materials.

“Millions of [tons] of shell waste are produced globally each year, and most of it has no useful destination,” said Dr. Abass. “If we can divert even a fraction of that into low-carbon construction materials, the environmental gains could be significant.”

“It’s a simple idea with real potential to reshape part of the sector,” he concluded.