Dr Cyrille Dunant, Dr Pippa Horton and Professor Julian Allwood, have filed a patent and been awarded new research funding for their invention of the world’s first ever zero-emissions cement, according to an official press release.

Replacing today’s cement is one of the hardest challenges on the journey to a safe climate with zero emissions.

There are many options to make cement with reduced emissions, mainly based on mixing new reactive cement (clinker) with other supplementary materials.

However, until now, it has not been possible to make the reactive component of cement without emissions. The new invention achieves this for the first time.

The inspiration for Cambridge Electric Cement struck inventor Cyrille Dunant, when he noticed that the chemistry of used cement is virtually identical to that of the lime-flux used in conventional steel recycling processes.

The new cement is therefore made in a virtuous recycling loop, that not only eliminates the emissions of cement production, but also saves raw materials, and even reduces the emissions required in making lime-flux.

The new process begins with concrete waste from demolition of old buildings. This is crushed, to separate the stones and sand that form concrete from the mixture of cement powder and water that bind them together.

The old cement powder is then used instead of lime-flux in steel recycling. As the steel melts, the flux forms a slag that floats on the liquid steel, to protect it from oxygen in the air.

After the recycled steel is tapped off, the liquid slag is cooled rapidly in air, and ground up into a powder which is virtually identical to the clinker which is the basis of new Portland cement.

In pilot-scale trials of the new process, the Cambridge team have demonstrated this combined recycling process, and the results show all the properties of cement made by today’s conventional process.

There have been other projects aimed at making the construction industry ”greener”. At the beginning of February, Holcim, one of the most important building materials company, announced a partnership with ENI to transform CO2 from carbon capture into green cement.

Also, mid May, researchers at Nanyang Technical University announced that they managed to create biocement from waste, making the alternative more sustainable and greener by using urine and carbide sludge.