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Low Emissions Intensity Lime and Cement

Periodic Reporting for period 4 - LEILAC (Low Emissions Intensity Lime and Cement)

Reporting period: 2019-10-01 to 2021-06-30

The LEILAC (Low Emissions Intensity Lime And Cement) project will pilot a breakthrough technology that aims to enable the cement and lime industries to capture the CO2 emissions emitted from the raw limestone as it is processed, for minimal environmental or economic cost. The Calix process does not involve any additional processes or chemicals, and simply involves a novel “calciner” (kiln) design.

The context and challenge
The adoption of the Paris Agreement, ratified by 175 countries, provided the clear objective of keeping a global temperature rise of well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase even further to below 1.5 degrees Celsius.

This is not an easy commitment to reach for the cement or lime industry - responsible for 8% of global CO2 emissions. Cement and lime provide vital services to our society, with essential products that are low cost and very efficiently produced. Since 1990, major efforts have been made to reduce emissions, including improvements to energy efficiency, use of alternative and waste fuels and clinker substitution.

However, complete decarbonisation of this industrial sector is far harder than many others, as most CO2 emissions are released directly and unavoidably from the processing of the limestone. These “process emissions” are in addition to the CO2 released from the combustion of fuels used to power the process (representing around two-thirds of a plant’s total emissions, depending on the fuel used).
A new capture approach is being introduced. Calix’s new process of ‘indirect calcination’ focuses solely on the cement, lime and magnesia sectors, ensuring that the relatively pure, unavoidable, CO2 released from the limestone itself in the precalciner is not contaminated by either air or flue gases.

The principles of the technology
Calix’s LEILAC technology re-engineers the existing process flows of a traditional calciner by indirectly heating the limestone. This system enables pure CO2 to be captured as it is released from the limestone because the furnace exhaust gases are kept separate. This innovation requires minimal changes to the conventional processes for cement, and simply replaces the pre-calciner. This simple and effective solution requires no additional chemicals or processes.
The design should also capable of working with a variety of energy sources: from natural gas, electricity, to alternative fuels. It can also be used in conjunction with other existing carbon capture techniques.

The objectives of the pilot
The LEILAC1 project involved the construction of a pilot plant at the HeidelbergCement plant in Lixhe, Belgium. Extensive research, development and engineering will be necessary to design and construct the pilot. The objective is to then run the high temperature pilot in a standard operational environment with a variety of extensive tests to see if the technology performs as expected, confirming the purity of the separated CO2 and that the product is not negatively impacted. It will aim to treat around 5% of a typical cement plant’s capacity.
The project is led by Calix, the company behind the LEILAC technology. Providing funding, guidance and technical input, the project’s industrial partners are HeidelbergCement, CEMEX Research Group AG, Tarmac, Solvay and Lhoist. TNO has undertaken key research into the primary areas of risk: providing steel analysis, corrosion and fouling testing and analysis. Imperial College London has undertaken materials analysis, kinetics modelling and computational fluid dynamics (CFD) modelling. Process Systems Enterprise carried out initial modelling of the technology, and Quantis has developed a Life Cycle Analysis study. The Carbon Trust was responsible for public engagement. It is supported by an External Advisory Board formed by CEMBUREAU, ECRA, EuLA, and GCCA.

LEILAC has now undertaken extensive research and development on critical issues facing the application and scale up of this technology, and successfully reduced all the major risks. There is now a good understanding and characterisation of the feed materials; a comprehensive understanding of the corrosion and scale risk resulting from testing and assessment; an informed choice of materials and equipment for the reactor; and confidence in the design and outputs, based on significant tests, process, kinetics and CFD modelling.

Led by HeidelbergCement and supported by Calix, the construction of the pilot was conducted safely, on schedule and under budget. This was a significant achievement.

With the commencement of operations, albeit not yet pushed to maximum capacity, trials of the LEILAC pilot are extremely promising and the technology is working as expected. It has successfully demonstrated that limestone can be processed; that the CO2 is successfully separated; that there have been no negative impacts on the host plant, and no impact on clinker production; and that the pilot is safe and easy to operate, with no safety incidents.

Significant dissemination has taken place – far more than expected. The project held two Innovation in Industrial Carbon Capture Conferences, with high level speakers from industry, NGOs, international organisations, and other capture projects. The LEILAC website provides information in English, Dutch, French, and has been recently extended to also provide German and Spanish.
The LEILAC pilot unit has undergone extensive testing. The research has enabled a good understanding of the process demands and performance parameters of the technology, and has demonstrated that the technology works sufficiently to begin scale-up demonstration in the cement sector or provide a near-term CO2 capture option for the lime industry. This will significantly advance European industry, by enabling them to capture their unavoidable process emissions at low cost, effectively and at low-risk.

A Cement and Lime industry CCS Roadmap has been developed. This Roadmap is based on the outcomes of the LEILAC pilot’s construction and testing, and includes a full-scale techno-economic study, Life Cycle Analysis, and retrofit report. This illustrates how effective, and important, the technology could be for our society - and how it is being designed to be cheaply and effectively rolled out globally.

Increasing interest is being shown by industry, governments, reporters and wider society about the impact that this technology could bring – both for Europe and globally. Dissemination, site visits, events and presentations have been made widely in support of this expressed interest. As articulated within the project’s vision, a low-cost, simple method of enabling industrial decarbonisation is urgently needed. All options need to be explored as fully and as urgently as possible - and this which is why, at all of LEILAC’s events, all European decarbonisation projects are encouraged to present their activities.

Ultimately LEILAC seeks to be one of the technologies that provide industry with a cost-effective, timely option for producing low carbon cement and lime.
The furnace sections being moved to the work site
Direct Separation reactor design
Top view of the completed LEILAC pilot plant
The completed LEILAC pilot plant
3D render of the LEILAC pilot plant