"Calcination Process for Lime Decarbonisation"

Podcast feat. James O’Loghlin & Adam Vincent

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“Calcination Process for Lime Decarbonisation” feat. James O’Loghlin & Adam Vincent

Welcome to the sixth Episode of INNOVATING FOR THE EARTH

with innovation expert and radio and TV presenter James O’Loghlin

In this 6th Episode of our Podcast: Innovating for the Earth, innovation expert and radio and TV presenter James O’Loghlin speaks with Calix General Manager Adam Vincent about lime decarbonisation.

Together, they explore how Calix’s LEILAC (Low Emissions Intensity Lime and Cement) carbon capture technology can help significantly reduce lime’s impact on the environment.

As environmental regulations toughen, and shareholders and stakeholders place increasing pressure on companies to reduce greenhouse gas emissions, lime producers need solutions quickly to help mitigate their CO2 emissions.

Calix’s LEILAC (“Low Emissions Intensity Lime and Cement”) Technology is available now to efficiently separate the CO2 emitted in lime production.

Calix’s LEILAC Technology captures the process CO2 emissions that are generated when limestone is heated. These emissions are unavoidable regardless of the fuel type and can constitute up to 75 per cent of CO2 emissions from a lime plant. The remainder comes from burning fuel.

Further advances in Calix’s LEILAC Technology, such as the ability to electrify the whole of the heating requirement, and power it from renewable energy, means that zero-emissions lime manufacturing can be achieved.

“The current objective facing the lime industry and governments is threefold: to maintain economic prosperity, meet lime market demand, while dramatically lowering CO2 emissions. Calix (LEILAC) aims to meet this global challenge as quickly as possible.” Comments Adam Vincent, General Manager Lime Decarbonisation.


Calix files a new patent for zero emissions iron and steel

Calix is pleased to announce the filing of a patent covering a new application of its core technology for the production of zero CO2 emissions iron and steel.

Iron and steel making sits just behind cement and lime as the second largest source of man-made industrial CO2 emissions, estimated at 7% of the global total, or around 2.6 billion tonnes per year.


80 to 85% of the industry’s CO2 footprint is associated with the production of iron, as 90% of all iron is produced by metallurgical coal- and coke-fuelled blast furnaces, producing approximately 1.8 tonnes of CO2 per tonne of iron produced.

Iron produced via direct reduction of iron ore using a “syngas” of hydrogen and carbon monoxide (made from natural gas) in a shaft furnace is a less CO2 intensive method, at around 0.6 tonnes of CO2 per tonne of iron, however this process route has traditionally been more expensive, and hence only 10% of the world’s iron is produced by this method. The method requires cheap natural gas, as well as pelletisation of iron ores to prevent fines loss.

Methods to lower the carbon footprint of iron production have started to consider using “green” hydrogen as the major reductant instead of natural gas and coal. The use of hydrogen in blast furnaces is being tested, but there will be limits on the amount of coal it could replace due to a reduction in the conversion rate of iron ore to iron. A “direct reduction process” with hydrogen is currently being assessed in the HYBRIT process in Sweden with SSAB, Vattenfall and LKAB. However as with a normal direct reduction process, the iron ore requires pelletisation, and ultimately consumes about 72 kg of hydrogen per tonne of steel (Source: McKinsey & Co -Decarbonisation Challenge for Steel, P9).


Following the production of iron, steel is then produced either by removal of impurities in a basic oxygen furnace (usually following a blast furnace) or electric arc furnace (usually following a direct reduction process). Both production routes allow for the recycling of scrap steel at this point. In both routes, impurities in the steel need to be removed, and this is partially achieved via the addition of lime both before and during the steelmaking process, typically between 25kg to 70kg of lime per tonne of steel, or about 46 million to 130 million tonnes of lime.

Diagram above is from the European Steel Association


Calix’s “ZESTY” (Zero Emissions Steel TechnologY) Iron process involves the use of Calix’s core “kiln” technology to reduce iron ore to iron in a hydrogen atmosphere at between 600oC to 800oC, about 1000oC lower than a conventional blast furnace, due to the ability of Calix’s technology to handle small particle sizes in a controlled atmosphere. Calix’s kiln can also be easily electrically heated and handle intermittent operation – and thus the process can be energised via renewable energy sources. Because expensive hydrogen is not consumed as a fuel, and only as a reductant, Calix’s process is targeting the theoretical minimum hydrogen use of 54 kg per tonne of iron.

In summary, Calix’s ZESTY iron technology allows for:



Calix’s “ZESTY” (Zero Emissions Steel TechnologY) Steel process involves the use of the ZESTY Iron process feeding a standard (continuous) electric arc furnace (C-EAF), with the addition of a LEILAC kiln to produce zero-emissions lime. The “hot, active” lime produced from the LEILAC technology can be directly fed to the ZESTY reactor, and in addition any extra CO2 required in the C-EAF for the final steel mix can be fed directly from the LEILAC reactor. Some extra lime from the LEILAC reactor can also be used to scrub any excess carbon dioxide, as well as other pollutants such as sulphur compounds, from the exhaust gas from the C-EAF in a carbonation step (“CL” in the diagram). In addition to the advantages of Calix’s ZESTY Iron process, Calix’s ZESTY Steel technology allows for:



Professor Paul Fennell – Professor of Clean Energy at Imperial College London said “The Fennell group at Imperial College is currently conducting its own independent investigation of the use of powder gas reactors, such as that embodied by ZESTY for iron and steel production and have found no substantial obstacles so far in our studies. We believe that tight control of particle size to prevent internal diffusion limitation will be necessary, and there will no doubt be other phenomena to be considered as the technology is scaled. However, the production of iron from iron ore is clearly the most obvious next generation use of the Calix technology, and one that I consider to have great potential”.


Calix’s patent outlines the use of Calix’s core technology to produce zero emissions iron and steel. The technology will need to be scaled and tested, and the patent upheld, to achieve commercial success. Initial testing is taking place at Imperial College in London. If positive results are confirmed, Calix will then conduct scale-up testing at the Company’s Bacchus Marsh facility with ores from a potential customer, who Calix has already engaged in discussions.

CEO of Calix Phil Hodgson said: “These are early days for the Calix ZESTY technology, however, given the materiality of both the potential for our technology in iron and steel production and the size of the environmental challenge, being similar to the one our LEILAC business is addressing, we will be pursuing this opportunity as quickly as possible – the world cannot wait any longer.

Calix appoints internal seasoned executive as CEO of its CO2 Business

Calix is pleased to announce the appointment of seasoned Calix executive Dan Rennie as CEO of the “LEILAC Group” – Calix’s CO2 mitigation business.

Calix CEO Phil Hodgson said “After an extensive global search program via an executive search firm, and following-on from the investment by Carbon Direct of €15m into our CO2 business to accelerate commercialisation of the LEILAC technology, I am very pleased to confirm that a seasoned Calix executive is being promoted to lead our CO2 business as CEO. Dan Rennie has been instrumental in winning grant funding for, and co-ordinating, both our LEILAC-1 and LEILAC-2 projects, as well as developing a deep global network of cement and lime companies, decarbonisation stakeholders, policy makers and engineering companies. He has been instrumental in raising the profile of Calix’s LEILAC technology from an unknown new technology only a few years ago to the European and then world stage. After assessing our internal executive talent against the best we could find externally, it is great to see one of our own filling this role, with the full support of our Board and our co-investor in this business, Carbon Direct.”

We are ecstatic that Dan will be leading the LEILAC Group as CEO,” said Josh Dienstag, Carbon Direct’s Chief Investment Officer and LEILAC Group director. “Dan brings technical and commercial expertise as well as passion that are key assets to the company during this important phase of growth.”

Dan Rennie said “It is both a privilege and an honour to be selected to lead Calix’s business efforts for decarbonising hard-to-abate industries using its low-cost carbon capture technology. The teams involved in developing this breakthrough technology over Calix’s short history are an exceptionally talented set of individuals – immeasurably supported by the dedicated efforts of our industrial, academic and engineering partners.

With cement alone being responsible for 8% of global CO2 emissions, we are at a watershed moment to bolster collective efforts to meet the goals of the Paris Agreement and stabilise the climate. While most of the emissions from cement and lime are unavoidable, solutions are available and I believe that Calix’s LEILAC technology has a leading role to play in decarbonising these industries. I look forward to building on the successes to date and working with our partners, clients and stakeholders to develop this into an effective global solution.”

Dan worked in the electricity sector, prior to moving to the Global Carbon Capture and Storage Institute. He also ran the European Commission’s CCS Network, then joined Calix in 2014 to investigate how Calix’s technology could be applied to the cement and lime industries. Dan holds a Master’s degree in history from St Andrews University, and is based in France.

Using Lime to Store Energy: SOCRATCES

Using Lime to Capture CO2: Project ANICA

Decarbonising Cement by scalling Calix technology with Andrew Okely

LEILAC Virtual Tour with Adam Vincent

Leilac Roadmap 2050



The Cement and Lime industries play a vital role in our society

Cement is used in our roads, buildings, homes, offices and almost all our infrastructure. Lime is used in a variety of applications including in the iron & steel, chemical, paper, pharmaceutical, drinking water, food, and farming industries. EU recognised these sectors as being ‘indispensable’ to the economy. Responsible for 8% of global CO2 emissions, global cement and lime demand will increase due to the global population growth and the trend of further urbanisation. They play a vital part of our society and

The Cement and Lime industries are dedicated to decarbonising

Cement and lime industries, both through their associations and individual corporate pledges, have made clear commitments to carbon neutral emissions production by 2050.

The LEILAC process (Direct Separation) represents a low cost, eco-efficient means of capturing process CO2, and can be run on renewable energy

A variety of approaches and technologies are being developed to capture the CO2 emissions from the cement industry, and they all need to be urgently developed and scaled up. Supported by industry and the EU, the proven LEILAC technology captures unavoidable process CO2 emissions for minimal expense, as it as it does not need additional processes or chemicals. It can work in synergy with other technologies and approaches. It can also be fully powered by renewable energy and/or hydrogen, and all units will be ‘electrification’ ready.

These industries recognise that reaching carbon neutrality requires the use of carbon capture, utilisation and storage (CCUS)

Two-thirds of emissions from the production of cement and lime are unavoidable ‘process emissions’. While several approaches can be taken to reduce the volumes of CO2 generated – and these should be pursued strongly – the most viable means of ensuring process emissions do not reach the atmosphere is by capturing and permanently safely storing the CO2 typically in minerals or by sequestration. Using the CO2, for example in the chemical industry and for creating synthetic fuels, may be an important enabler for capturing CO2 from the cement and lime industry.

The LEILAC process is being designed for efficient, global roll out

A LEILAC module addressing 20% of a cement plant’s emission will begin constructed in 2022. The intent behind the commercial, global rollout of the technology is for the modular, scalable design to capture the process emissions from a plant of any size. The designs will eventually be ‘blueprinted’ and applied by engineering firms on a global basis to cement and lime plants, enabling localised expertise to be developed and used.

Appropriate long-term incentive frameworks and public financing for early movers are critical

Effective policy environments and incentive mechanisms are required globally to ensure that vital industries can continue to operate, while taking necessary decarbonisation steps. Public subsidies and investments are required to allow these technologies to continue to be quickly developed and installed globally. Support is required to enable and widely deploy transport and storage infrastructure, ensuring the captured CO2 does not reach the atmosphere.

CO2 transport and storage availability is vital to enable industrial decarbonisation, and without it the ability for our society to reach it climate change ambitions will be limited

The consortium considers the development and availability of transport and storage infrastructure to be vital for decarbonising the cement and lime industries. Unlike examples in the power and refining sector, the volume of CO2 to be stored per plant is less. This opens local storage opportunities and industries. Given the very small size of most of the cement and lime players, steps must be taken to quickly develop storage sites of all sizes; ensure larger storage developments are appropriately sized for 2050 (particularly if using public money and only facilitating bigger players); and enable fair access.

Societal acceptance and Government support are essential

While pursuing every option available to decarbonise, the cement and lime sector needs the help and assistance of our society (as both project stakeholders and product consumers)as it decarbonises. On a local level, that can range from small increases in prices of cement, through to active support of decarbonisation projects so they remain competitive.

“CO2 Direct Separation for cement decarbonisation” feat. James O’Loghlin & Simon Thomsen

Welcome to the fourth Episode of INNOVATING FOR THE EARTH

with innovation expert and radio and TV presenter James O’Loghlin

In the fourth Episode, James O’Loghlin talks with Simon Thomsen, Project Engineer at Calix and responsible for the R&D on the LEILAC 2 project about how LEILAC Carbon Capture technology is applied to the cement industry.

The LEILAC technology is based on Calix’s Direct Separation technology, which aims to enable the efficient capture of the unavoidable process carbon emissions, derived from its original application in the magnesite industry. Applying and scaling up the technology to the cement industry carries a large number of risks. To quickly and effectively apply this technology, the European-Australian collaboration LEILAC projects include consortia of some of the world’s largest cement, and lime companies, as well as leading research and environmental institutions.

LEILAC will deliver a stepchange in the efficiency of capturing CO2 emissions. See www.project-leilac.eu for more information and follow it on twitter under ‘ProjectLEILAC’.

LEILAC project case study

The LEILAC (Low Emissions Intensity Lime And Cement) projects will seek to prove a new type of carbon capture technology can be applied to the cement and lime industries, called Direct Separation. This technology provides a common platform for CCUS in both the cement and lime industries, and seeks to effectively “future-proof” these industries against tighter emissions standards for CO2 emission reductions and CO2 capture.

The LEILAC1 project developed, built and operates a pilot plant at the HeidelbergCement plant in Lixhe, Belgium to demonstrate this technology is unique because it aims to enable the capture of the unavoidable process CO2 emissions from both industries without significant energy or capital penalty other than compressing the CO2.

The LEILAC pilot is designed to run a throughputs of up to 240 tonnes per day, carry out fundamental research on the process demands and performance, and demonstrate that the technology works sufficiently robustly to begin scale-up planning.

The LEILAC2 project aims to scale-up the direct separation technology developed and tested in LEILAC1 and to build a Demonstration Plant that will separate 20% of a regular cement plant’s process emissions –around 100 ktpa of CO2.