Take the European Union, India, or fourteen billion cubic meters of limestone and clay mixture every year, and you’ll find the carbon impact of cement production around the world. Just after the United States and China, galloping urbanization has made clinker a production three times more polluting than the air sector. It is estimated that 150 tonnes of concrete are poured every second… A staggering flow, knowing that one tonne of cement would correspond to 1 tonne of carbon dioxide released into the atmosphere.
The most problematic thing is not even this observation. But the outlook. Industry is represented by a few large manufacturers with overpowered lobbying, as well as inalienable price competitiveness. Production methods are also rigid. To create the famous clinker, it is necessary to heat the mixture to more than 1400 degrees. The ovens, attributed to this activity, are fueled by fossil combustion. It must be said that to climb to such high temperatures, more efficient alternative solutions are rare. But technological development is not dead for all that.
Coolbrook, the startup that tackles cement kilns
When COP27 returned to Egypt, a certain Joonas Rauramo, CEO of the Cookbrook company, nevertheless wanted to be optimistic. He is leading a team, based in Finland, set to demonstrate next month that an electric kiln can take over cement production for decades to come. In his hands, innovation is called RotoDynamic. It is already protected by patent as for its founder, it could constitute a solution to save 2.4 billion tons of CO2 emissions per year.
“The main reason we wanted to be at COP27 was to get the message across that there are technologies available to solve the problem in industries considered hard to scale down – or impossible to electrify – that there are technologies that can help solve these problems”he said, relayed by the magazine Fortune. RotoDynamic has not yet fully proven itself, but the goal was to demonstrate that a solution was possible.
To date, Coolbrook and its electric oven have been able to raise the temperature to over 650 degrees celcius. The first tests at more than 1000 degrees are scheduled for next month. To achieve this, its engineers relied on the principle of friction. By accelerating the air, the particles rub against each other and create heat, a principle that would work on renewable energy in the case of their innovation. “There’s an electric motor that spins these blades, and they’re used to accelerate the air to supersonic speed, which is then rapidly decelerated again, converting kinetic energy into heat.”, specified Joonas Rauramo.
In all, the share of greenhouse gas emissions from kilns in cement production would be around one third. The rest would come from calcination, this chemical process for the creation of cement. By decarbonizing the heating process, a large part of the emissions would disappear, but nothing would change on the rest. In an article, the McKinsey company spoke of an “inevitable” process that would make the goals of carbon neutrality in 2050 “particularly difficult for the industry”.
A French startup to the rescue
At the French company Hoffmann Green Cement Technologies, the impossible is not part of the vocabulary. By surfing on new measures put in place by the State, this startup launched in 2014 has developed a new low-carbon cement based on “a clever mix of cold-activated binders”, as detailed by our colleagues from France 3 Pays de la Loire – the startup being based in Vendée. Production started two years ago now and three production sites are planned to satisfy the order book.
“We have already signed partnerships with major French construction companies who want to set foot in the stirrup”, explained on television Julien Blanchard, the CEO of the company which was introduced on the Paris Stock Exchange in October 2019. After a sharp correction in its title (-40%), the company still capitalizes 153 million euros today. Its investments will continue to weigh on its balance, but the young company is aiming for profitability by 2025. This year, 250,000 tonnes of low-carbon cement are planned by Hoffmann Green Cement Technologies.
The price will remain, which for the time being is still 60% higher than conventional cement. Faced with solutions like that of Coolbrook, to reduce the carbon impact via ovens, the French startup could encounter difficulties in establishing itself in the short term. In 2026, it expects that said to sell 550,000 tons, to reach a turnover of 120 million euros and an Ebitda of 40%. At this stage, Hoffmann Green Cement Technologies would then represent 3% of the national market.