Innovation in Building Materials: Cement
Over the years, we have seen a surge in demand for sustainable energy or net-zero carbon emissions. The drive to reduce the level of greenhouse gas emissions that impact the atmosphere has increased. Global urbanization has resulted in an increase in the demand for new infrastructure and buildings, with concrete being the second most consumed material behind water. Despite cement’s relatively low carbon dioxide emissions, it is responsible for 8% of human-made carbon dioxide emissions due to its abundance in use as a traditional building material.
Due to this, the cement producers are striving to significantly reduce the carbon emissions output while also satisfying the growing demands of the global market.
Reducing Carbon Emissions With Concrete
In the future, we will be able to permanently mitigate heat-trapping emissions by capturing, utilizing, and storing CO2 across multiple manufacturing phases and components of concrete. Shortened down to CCUS, the diverse set of technologies being developed opens up the possibility of commercializing an innovative climate solution that is similar to the innovation breakthroughs that were brought about by electric vehicles in the automobile industry. Here’s three ways this is being done and how they work.
In its simplest form, concrete is made through a mixture of cement, water, and granular material known as aggregates. Portland cement is the most commonly used cement base that is primarily made of limestones that is then heated to extremely high temperatures, releasing tons of CO2. Blue Planet, a Californian based company with a mission to reduce carbon emissions, has developed a new method of concrete production by pulling CO2 from the air to create synthetic limestone to replace traditionally mined limestones in cement Every ton of synthetic limestone absorbs 440kg of CO2, permanently embedding it. This method can actually improve the tensile strength of concrete while also being a scalable solution to reducing CO2 emissions.
CO2 can be utilized to help speed up the curing process. By injecting CO2 into fresh concrete, we can trap it while also adding to the compressive strength of the finished concrete. This results in 60% less emissions and we can see use cases of it happening. For example, LinkedIn will build a new building in Mountain View, CA, using concrete cured with this method. This is done to help reduce the overall company’s carbon footprint by 75% in 2030.
Concrete storage works similar to curing in that CO2 is injected into concrete but is instead used to reduce concrete demand by increasing its strength and quality. For example, a company named CarbonCure recycles CO2 back into fresh concrete, where it undergoes a mineralization process and becomes permanently embedded. This will increase the compressive strength, meaning less cement is required to achieve a certain strength threshold. Pouring less concrete means more money saved and reduced carbon emissions by increasing quality instead of quantity.
The innovations in concrete and cement-based products are changing design concepts and construction industries. Concrete has evolved proactively over the past 2000 years. The fact that concrete is continuously evolving and transforming simply means that there will be a lot to look forward to over the next few years.