A British company has developed a new type of cement that can suck up carbon dioxide from the atmosphere. Its use could transform the cement production from a harmful emitter of CO2 into an environmentally beneficial process.
Traditionally, cement requires intense heat to burn the raw material used in production – typically limestone. A large amount of energy is needed to generate this heat, and so CO2 is released. The effect is further compounded by the release of CO2 from the burning limestone itself.
Novacem, based in London, have created a new mixture of cement based on magnesium silicates. It requires much lower temperatures during production, and as it sets it actually absorbs CO2 from the atmosphere, making the material actually carbon negative.
The company claims that in a normal lifecycle their cement can absorb 0.6 tonnes of CO2 per tonne of cement. This is a dramatic improvement over the regular stuff, which emits about 0.4 tonnes of CO2 per tonne of cement.
There are doubts over the suitability of the new cement, however. A spokesperson for the British Cement Association said that although much work is done in laboratories on new types of cement, they aren’t yet ready for the market:
“The reality is that the geological availability, and global distribution, of suitable natural resources, coupled with the extensive validation needed to confirm fitness-for-purpose, make it highly unlikely that these cements will a be realistic alternative for volume building.”
Chief scientist of Novacem, Nikolaos Vlasopoulos, countered such claims, as an estimated 10,000 billion tonnes of magnesium silicates are available worldwide. He acknowledges that the cement requires further testing until it is safe for use in buildings, but is confident that Novacem is the way forward.
For myself, I have to applaud Novacem for their efforts. Cement might not be glamorous, but it’s scientific developments such as these that will help us tackle climate change. No one is really going to get excited about a new type of cement, but adapting our existing industrial methods will certainly make a difference.