Articles tagged with "cement"
CO2-grabbing biochar delivers a stronger, denser cement mix
A recent study from Hefei University of Technology reveals that modified biochar, derived from corn-straw waste, can both capture CO₂ within cement and enhance the material’s strength and durability. Cement production is a major contributor to global CO₂ emissions, accounting for nearly 8%, and current carbon capture methods are often impractical or costly. The researchers focused on biochar’s internal sedimented particles (SP), which exhibit significantly higher CO₂ adsorption than untreated biochar. By applying controlled pyrolysis and alkali modification, they produced a biochar variant (notably MBC500) that promotes internal carbonation and calcite formation, densifying the cement microstructure and improving compressive strength. Extensive testing—including BET surface area analysis, FTIR, Raman spectroscopy, and mechanical tests—showed that alkali treatment refines biochar’s micropores, enhancing CO₂ adsorption sites despite reducing overall surface area. The SP component demonstrated superior adsorption capacity, with kinetic modeling indicating rapid physical adsorption combined with some
materialsbiocharcementcarbon-captureconcrete-strengthsustainable-constructionCO2-reductionTextile ash boosts cement strength by 16% in new material test
Researchers at Kaunas University of Technology (KTU) in Lithuania have discovered that textile waste ash can enhance cement strength by up to 16% when used to replace 7.5% of traditional cement. This innovation not only improves the compressive strength of concrete but also offers a sustainable solution to two pressing issues: the management of textile waste and the reduction of carbon emissions in the construction industry. Textile waste, which is difficult to recycle due to fiber blends and synthetic additives, is typically landfilled or incinerated. By converting textile waste into ash and recovered fibers, KTU scientists are turning it into a valuable resource for cement production, supporting the EU’s circular economy goals. The research also highlights additional benefits, such as improved freeze-thaw resistance in concrete containing polyester fibers recovered from discarded clothing, which enhances infrastructure durability. Moreover, textile waste can be thermally processed into carbon-rich granules that, when burned, produce ash suitable for cement use. This approach aligns with broader efforts to reduce
materialscementtextile-ashwaste-reuseconcrete-strengthsustainable-constructioncircular-economyWhy cement is climate's hardest challenge
The article highlights cement as one of the most significant climate challenges, responsible for about 8% of global CO₂ emissions—more than aviation and shipping combined. In 2022, the cement industry emitted roughly 1.6 billion tonnes of CO₂, with production at 4.1 billion tonnes annually and rising due to urbanization. China alone produces about half of the world’s cement, underscoring the scale of the problem. A key difficulty in reducing emissions lies in the chemical process of cement production: about 60% of CO₂ emissions come from the decomposition of limestone into clinker, not just from fuel combustion, meaning renewable energy alone cannot solve the issue. Despite efficiency gains since 1990, emissions could nearly double by 2050 without transformative changes. Engineers are pursuing multiple strategies to lower cement’s carbon footprint, particularly by reducing clinker content through blending alternative materials, often industrial byproducts. Ground granulated blast-furnace slag (GGBS), a steelmaking
materialscementcarbon-emissionssustainable-constructionindustrial-byproductsCO2-reductionclimate-solutionsHow CLT Displacement Makes Steel & Cement Decarbonization Realistic - CleanTechnica
The article discusses how cross laminated timber (CLT) serves as a critical lever for decarbonizing the traditionally carbon-intensive steel and cement industries by displacing these materials in construction. While CLT is often highlighted for its benefits in faster, more affordable, and lower-carbon housing, its broader impact lies in reducing global demand for cement and steel over time. This substitution effect, especially in mid-rise residential and commercial buildings, contributes to bending demand curves downward, making decarbonization of heavy materials more achievable. The article builds on previous analyses that positioned CLT and modular construction as key solutions to housing shortages and embodied emissions, emphasizing the need for integrated value chains and government policy support to scale CLT adoption. Contrary to conventional projections that assume steady growth in cement and steel demand aligned with GDP and urbanization, the article argues that demand will peak earlier and decline gradually due to several factors: the end of China's infrastructure boom, shifts in advanced economies from expansion to maintenance, efficiency gains, and
energymaterialsdecarbonizationcross-laminated-timbercementsteelconstruction-materialsChina develops cement that can cool itself by scattering heat
Researchers from Southeast University in China have developed a novel "supercool" cement that significantly reduces surface temperature by scattering sunlight rather than absorbing it. This cement, engineered with metasurfaces and a photonic architecture, achieves a high solar reflectance of 96.2% and an emissivity of 96% in the mid-infrared spectrum, enabling it to cool itself by radiative heat dissipation. Performance tests demonstrated the material’s robustness against mechanical stresses, abrasive forces, and harsh environmental conditions such as UV radiation, corrosive liquids, and freeze-thaw cycles. The cement also maintains plasticity for complex shapes and amphiphobic properties, making it versatile for structural applications in roofs and walls. The researchers adjusted the chemical composition of clinker particles to promote the self-assembly of reflective ettringite crystals and hierarchical pores, enhancing sunlight scattering and heat emission. Real-world testing on building roofs showed that the supercool cement could reduce surface temperatures by up to 9.72°F (5.
materialscementradiative-coolingmetasurfacessustainable-building-materialscarbon-emission-reductionphotonic-architectureRoman ruins inspire scientists to create cement from volcanic rock, no kiln required
Scientists at Stanford, inspired by ancient Roman observations, have developed a new type of cement made from volcanic rock that requires no kiln and produces significantly less carbon dioxide. The research draws on Pliny the Elder’s account from 79 A.D., describing how volcanic ash from the Puteoli region (modern Pozzuoli) naturally hardens into stone when immersed in water—a property that contributed to the durability of Roman structures like the Pantheon. Traditional cement production involves heating limestone above 1,400°C, releasing about 8% of global CO₂ emissions, making it a major contributor to climate change. Tiziana Vanorio and her team studied volcanic rocks beneath the Campi Flegrei supervolcano near Pozzuoli, which had naturally undergone heating and lost carbonate content, thus avoiding CO₂ release during processing. They developed a method to crush these volcanic rocks into a cement-like material that forms tiny internal fibers, providing strength without the need for steel reinforcement. This innovative cement mimics natural
materialscementvolcanic-rockeco-friendly-constructioncarbon-emissionssustainable-materialsRoman-concreteCleaner, stronger cement recipes designed in record time by AI
Researchers at the Paul Scherrer Institute (PSI) have developed an AI-driven approach to design low-carbon cement recipes up to 1,000 times faster than traditional methods. Cement production is a major source of CO₂ emissions, primarily due to the chemical release of CO₂ from limestone during clinker formation. To address this, the PSI team, led by mathematician Romana Boiger, combined thermodynamic modeling software (GEMS) with experimental data to train a neural network that rapidly predicts the mineral composition and mechanical properties of various cement formulations. This AI model enables quick simulation and optimization of cement recipes that reduce carbon emissions while maintaining strength and quality. Beyond speeding up calculations, the researchers employed genetic algorithms to identify optimal cement compositions that balance CO₂ reduction with practical production feasibility. While these AI-designed formulations show promise, extensive laboratory testing and validation remain necessary before widespread adoption. This study serves as a proof of concept, demonstrating that AI can revolutionize the search for sustainable building materials by efficiently navigating complex chemical
materialscementartificial-intelligencemachine-learninglow-carbonsustainable-materialsconstruction-materialsLow-grade clay turned into powerful cement for green construction
materialscementsustainable-constructionenvironmental-impactclayconcreteengineering