If cement production were a country, it would be the world’s third largest greenhouse emitter in the world, behind China and the U.S., accounting for 8% of global greenhouse gas emissions.
Cement is also one of the hardest sectors to decarbonize, partly because combusting fossil fuels is, so far, the only way to produce the extreme temperatures necessary in production. But new tech developments are providing hope for this “hard to abate” industry.
“The key reason why we wanted to be at COP27 was to bring the message that there are technologies available to solve the problem in industries that are considered ‘hard to abate’ or impossible to electrify, that there are technologies that can help in solving these challenges,” says Joonas Rauramo, CEO of Finland-based Coolbrook, after returning from Egypt.
Coolbrook, which has partnerships with industrial powerhouses ABB, Shell and Cemex, has patented an electric heating process to replace the traditional coke and gas-fired furnaces integral to industrial cement production. Coolbrook says the process could save 2.4 billion tonnes of carbon emissions a year.
The so-called RotoDynamic Heater generates heat without combustion, by accelerating air to generate friction and heat, forming a kiln powered by renewable electricity that can be used in industrial processes including cement, steel, and petrochemical production.
“If you think of the machine, it looks and works a little like a reverse jet engine,” Rauramo says. “There is an electric motor that is rotating these blades, and they are used to accelerate air to supersonic velocity, which is then slowed down again rapidly, converting kinetic energy into heat.”
According to Coolbrook, their heater system has successfully generated temperatures up to 650°C and is capable of heating to over 1000°C, although the company has yet to run such extremes. Coolbrook aims to pass that milestone in December, when it pilots its technology in a factory setting.
Electrifying cement production doesn’t fully abate greenhouse gas emissions from production, as the chemical process in cement manufacturing, calcination, produces carbon dioxide, too. According to McKinsey, roughly two-thirds of emissions associated with cement production come from calcination; most of the other emissions come from heating.
Mitigating carbon emissions from cement manufacturing entirely would require developing effective carbon capture technology (which other companies are trying to do). Meanwhile other alchemists are attempting to utilize concrete as a carbon sink, by injecting carbon dioxide into the slurry. The carbon content reportedly creates a stronger concrete while also reducing the need for cement, which is a binding agent in concrete.
Rauramo is, of course, optimistic about the future of decarbonizing heavy industry, comparing development in the nascent electric furnace industry to the slow early growth of solar and wind power.
“Wind and solar felt like it started slowly, but that’s what you see when you have an exponential growth curve. In the beginning it looks like it’s slow but, once things get moving, the change happens really quickly,” Rauramo says.
Eamon Barrett
greeninc.news@gmail.com
@eamonbarrett88
