Transforming a kiln into a low emission solution: how Calix modernised an ancient technology and applied it to a net-zero future
Complementing carbon capture utilisation and storage, this technology can help industries play their significant part in reaching net-zero
From Ancient Egypt to Ancient Greece, humans have been using kilns for up to 10,000 years — depending on which archaeological history you read. And even with a few slight adjustments, the technology has barely changed since.
Then, in 2006, mining engineer Connor Horley and Mark Sceats — an academic with a background in physical chemistry — adapted the humble kiln for an important task. Their approach, which became the foundation technology for industrial innovations company Calix, re-thought the processing of a mineral called magnesite.
The traditional method of processing magnesite, a key ingredient of building products, has an emissions problem. When heated, half the weight of what you’re heating will transform into CO₂, which is then mixed with kiln or furnace gases and released out into the atmosphere.
Horley and Sceats’ solution was a kiln that kept the heated magnesite separate from the source of the heat itself. That way, furnace gases are kept apart from released CO₂, which can then be captured more efficiently and stored.
Calix chief executive Phil Hodgson might humbly call the company’s kiln-based platform technology “just a new way to heat stuff up”, but that sells the immense possibilities for industry and the push for net-zero very short.
The technology’s use isn’t limited to magenesite, either. It can also be used on limestone for the production of cement and limestone, making it a key innovation in the reduction of carbon emissions from industry.
Industry is responsible for nearly one quarter of the globe’s annual greenhouse gas emissions. Among those hard-to-abate emitters are producers of cement, chemicals, steel and aluminium — which all take large amounts of energy to produce.
It is low emission technologies, including the Calix innovation, working in combination with carbon capture utilisation and storage (CCUS) that can help industries play their significant part in reaching a net-zero future. But for Calix, the possibilities of the technology don’t stop there.
The full carbon picture
Bacchus Marsh, located 58.3 kilometres west of Melbourne, was where Calix had its humble beginnings. And while the technology was originally developed for magnesite, the bigger opportunity came with limestone because of its scale of use within cement and other industries.
These types of industries sit well in the middle of Calix’s lane — businesses that have sustainability challenges, working in sectors where it is hard to reduce carbon emissions. Same core technology. New application. And another continent needed for innovation to become reality.
To find a market large enough and interested enough in looking at a left-field piece of technology — then funding the idea and supporting it to develop it into a solution for industry — Calix had to first head to Europe. Now, their clients in the cement industry are some of the biggest producers in the world, including HeidelbergCement, CEMEX and CRH.
“In Australia, when we first started to use technology in the cement and lime industries, there was no interest and that's understandable. There was no incentive for anyone to do anything,” says Hodgson.
And making CO₂ easier to capture was just one part of the equation. The crucial next step is plugging into carbon utilisation and storage. As Hodgson puts it, “the two are intimately linked.”
“It's a little bit of chicken and egg — if you capture it, then what do you do with it?” Hodgson says.
“We need to work with those who have utilisation and transport and storage solutions to have a total solution for industry.”
For cement and lime, Hodgson estimates that 5 to 10% of captured emissions could be directed to utilisation opportunities such as new concrete formulations and aggregates. But there’s a limit. Beyond that 10% in global capture rates, safe storage connected to infrastructure becomes the focus.
Around the globe, that infrastructure and storage capacity is at various stages of development. In the US, that infrastructure is quite significant, from developed industries such as Enhanced Oil Recovery (EOR) to permanent sequestration in depleted gas and oil fields. In Europe — where CO2 has been stored safely offshore for decades — the infrastructure continues to develop. This is seen through oil and gas assets and projects that inject and safely store CO₂ in saline aquifers, where it can reform limestone.
In Australia, the infrastructure is also under development. LETA itself has invested in Glencore’s CTSCo Project in Queensland’s Surat Basin — a project that will be Australia’s first full-scale demonstration of CCUS on a coal-fired power plant. The project is designed to form the basis of Australia’s first carbon hub.
Chevron’s Gorgon project on the West Australian coast is the world’s largest carbon capture and storage project. It has the potential to store 4 million tonnes of CO₂ a year. Since August 2019, more than 4 million tonnes of greenhouse gas emissions have been injected.
Santos has been awarded a A$15 million grant from the Australian government’s Carbon Capture Use and Storage Development Fund for their Moomba CCS project in outback South Australia. These are just some of the wide range of projects and demonstration facilities being developed in the mining, construction and building materials industries.
According to Hodgson, this kind of infrastructure, and these kinds of projects are critical to delivering on the Paris Climate agreements.
“50% of global economies by GDP have now signed on to net-zero CO₂ by 2050. Sequestration has to be part of that solution,” he says.
Platforms to build on
In the world of computing and information technology, a platform serves as a basic foundation for development and support across other areas — the Intel processor is a good example.
As Calix’s technology approaches commercialisation, it too is becoming a platform technology. A magnesium-based version of the product is being developed into a water treatment solution for customers in industry, utilities and local governments who need to treat wastewater.
The same core technology is also being deployed for use with advanced battery materials. That’s because the kiln technology means furnace gases aren’t touching the particles, therefore reducing impurities.
Calix recently announced a partnership with Pilbara Minerals, which currently mines lithium ore and exports it to China to make lithium for batteries – but is looking to bring the production of lithium back to Australia. Calix is also exploring how the electrical elements on the kiln can be powered by renewable energy.
“So it really is the traditional platform technology,” Hodgson says.
“There are several different areas that the kiln can be applied to for CO2 capture — for renewable power, producing renewable power and also producing some really interesting materials for industries like the battery industry. It’s quite versatile.”
At the kiln face, Hodgson has been amazed at the progress of investment in low emission technology as part of the net-zero solution. He calls it a “radical shift” that has been triggered by the alignment of government, corporate and public interest in taking faster and harder action.
Key shareholders in some of the largest corporations — such as super funds and investment funds themselves — are demanding to see what actions companies are taking. Backed by legislation, places like the EU, the US and China are taking the lead.
“The changes over the last six months have been dramatic,” Hodgson says.
In his view, Australia hasn’t had the policy direction or consistency. The EU is legislating for net-zero by 2050 and will introduce a carbon tariff by 2023.
“So in Australia – even though we have set aside putting a price on carbon — suddenly if we want to be an exporter to those economies … we, by default, have a carbon tax,” he argues.
So which lead should Australia follow? Hodgson says Europe is ahead of the pack due to its combination of carrot and stick measures. The stick, he explains, is the emissions trading scheme.
Effectively, that means companies in industries like cement and lime have permits to freely emit CO₂. But the number of these free permits given out each year is falling as part of Europe’s push towards their 2030 goals.
If a company can’t or won’t reduce their emissions, they’ll now have to go to the market and buy a CO2 emissions permit — and tighter caps mean higher costs. The price of an emissions permit in 2018 was €5 per tonne. Now it’s €55 a tonne.
“Suddenly, companies are forced to do something,” Hodgson says.
“But you can’t just penalise industry and expect them to continue without some form of incentives and protection.”
The carrot from the EU comes in the form of generous research and development incentives and significant investment in infrastructure. And this approach is now being replicated in similar models by countries such as China.
The combination of carbon pricing and a corporate focus on non-financial factors — such as environmental, social and governance issues — in investment decisions means markets are more sympathetic to early-stage developments.
“We had to scrape and scrape to get the money together,” Hodgson says.
“Now it’s very core to a lot of companies understanding their CO₂ exposure and what they are doing about it.”
The horizon keeps getting closer
The net-zero imperative comes from a new alignment amongst key groups — governments, investors, shareholders and the community. That’s certainly the case in Europe, Hodgson says, where the alignment is stronger. But Australia is catching up quickly.
With a variety of low emission technologies needed to reach net-zero, Hodgson argues that maturation of CCUS as a technology is making it easier for the next generation of innovation such as the Allam Cycle and direct air capture (DAC). That translates to it being easier to raise the capital to develop the technologies and have government support.
“For technologies that were 10, 15 or 20 years away — such as DAC — the horizon is only shortening with the amount of capital flowing into development,” Hodgson says.
As for Calix, which has a key focus on developing core technology to solve global challenges, a runway of 10 years is a massive step on 5,000 years to rethink how the kiln works.
Sign up to get our latest projects straight to your inbox