Scientists at Nanyang Technological University, Singapore (NTU Singapore), have developed a groundbreaking 3D concrete printing method that actively captures and stores carbon dioxide (CO₂). This innovative approach offers a dual benefit: reducing the environmental impact of concrete production while enhancing the material’s structural performance.

Tackling Cement’s Carbon Footprint
Cement production is one of the largest contributors to global CO₂ emissions, responsible for 1.6 billion metric tonnes of CO₂ annually—around 8% of global emissions. Recognising the urgency of this issue, NTU researchers have devised a method that integrates carbon capture directly into the production process. Their work, detailed in the journal Carbon Capture Science & Technology, presents a promising pathway to a more sustainable construction industry.

The new method uses steam and CO2, both by-products of industrial processes, and injects them into the wet concrete during 3D printing. The captured CO2 reacts chemically with the concrete’s components, becoming a stable solid form embedded within the structure. Steam is also introduced to improve the absorption efficiency of the CO2.

Improved Sustainability and Performance
This innovative process not only reduces the carbon footprint of concrete production but also improves its material properties. Tests revealed that these 3D-printed concrete blocks can capture and store up to 38% more CO₂ compared to traditional printing methods. The blocks are also 36.8% stronger in weight-bearing capacity, which makes them suitable for robust construction applications. Additionally, the blocks demonstrated a 45.3% improvement in bending strength, meaning they are significantly more flexible and durable before breaking. The printability of the concrete was also improved by 50%, allowing for more efficient shaping and production processes.

Beyond these improvements, the method reduces the need for raw materials, construction time, and labour, further lowering the environmental and economic costs of building with concrete.

A New Era for Sustainable Construction
This innovative method demonstrates how material science can contribute to a carbon-neutral future in construction. By combining carbon sequestration with superior material performance, NTU’s research addresses two critical challenges: reducing the sector’s carbon footprint and meeting the growing demand for stronger, more sustainable building materials.

The potential applications are far-reaching, particularly for architects, landscape architects, and interior designers looking to incorporate eco-friendly materials into their projects. The improved mechanical properties and enhanced design flexibility of this 3D printed concrete make it an ideal choice for sustainable and circular construction practices.

Looking Ahead
The integration of carbon capture technology into building materials marks a significant step forward in reducing the construction industry’s environmental impact. With further advancements, this method could become a benchmark for sustainable material innovation, demonstrating how the problem of CO₂ emissions can become part of the solution.

Source: Designboom
Photos: NTU Singapore