FAQ - Frequently Asked Questions

1. What is the LEILAC project?


The LEILAC (Low Emissions Intensity Lime And Cement) project will seek to prove a new type of carbon capture technology that can be applied to the cement and lime industries, called Direct Separation.


LEILAC will develop, build and operate 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 CO2 emissions (about 60 % of total CO2 emissions) from both industries without significant energy or capital penalty other than compressing the CO2.


The LEILAC pilot will run 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 project’s results will be shared widely through ongoing publications, conferences and this website.


2. What is carbon capture?


Carbon capture is the process of selectively removing and capturing carbon dioxide (CO2) from industrial processes. It can then be used (eg as an industrial gas, or via technologies under development such as fuel recycling, etc) or permanently stored (eg sequestered in saline aquifers, or via technologies under development such as in building products or plastics).


Both the cement and lime industries have relatively high CO2 emissions with around the majority of their total CO2 emissions being released directly, and unavoidably, from the processing of limestone (which is 50 % by weight CO2). Carbon capture is the only means by which these industrial processes can dramatically reduce their emissions.


3. Where will the LEILAC pilot be located, why, and when?


The LEILAC project involves the construction of a Direct Separation pilot plant at the HeidelbergCement plant in Lixhe, Belgium. HeidelbergCement, as a major consortium partner, has provided the Lixhe site due to the plant’s already-advanced CO2 abatement strategies, including alternate fuels and waste processing.


In October 2016 the project passed its pre-FEED study. A final investment decision was taken in mid-2017. The pilot was completed on time and under budget in early 2019.


4. Which organisations are involved?


The LEILAC project has received €12m in grant funding as part of the European Union’s Horizons 2020 program. HeidelbergCement, CEMEX, Tarmac, Lhoist, Amec Foster Wheeler, Calix Limited, ECN, Imperial College, PSE, Quantis, Solvay and the Carbon Trust are all working to apply this critical technology to the cement and lime industries. All recognise that the long-term future of the cement and lime industries, which are both vital for many aspects of the European economy, hinge upon a reduction in their CO2 emissions. LEILAC’s project partners are collectively contributing an additional €9m to enable the application of this key technology.


5. Will there be more information?


We will extensively share our findings via this website and via a visitor-centre at the Lixhe site. We will also organise “open-days” for the general public.


6. How does the technology used in LEILAC work?


The LEILAC project is based on a technology developed by Calix called Direct Separation, which aims to enable the efficient capture of the unavoidable process emissions from lime and cement production. The process CO2 which is chemically released from the limestone accounts for more than 60% of the total CO2 emitted from lime and cement processing. It seeks to simply re-engineer the existing process flows of a traditional calciner, by indirectly heating the material being processed via a special steel vessel.

This unique system enables pure CO2 to be captured, in the case of limestone (CaCO3), as it is released during calcination to lime (CaO), as the furnace exhaust gases are kept separate. This elegant solution requires no additional chemicals or processes for a pure CO2 stream.   In principle, that means that the cement manufacturing process is not significantly altered.   From a process perspective, the additional cost of the process should be comparable to the conventional process.

7. Will there be any environmental impacts from the LEILAC pilot site?


No. The LEILAC project will be testing a slipstream from the existing cement making process. It will test separating pure CO2 through a new engineering design. No additional chemicals or process steps are used, and as a result the LEILAC pilot will not have any impact on the net emissions from the host cement plant at Lixhe.

8. What are the major technical barriers?

The major technical barriers are those being addressed in LEILAC – Increasing the operating temperature, mitigating corrosion and fouling of the steel, and identifying a commercially viable route to scale up to production from a feed of 10,000 kg/hr to about 300,000 kg/hr, preferably with a retrofit capability.These issues have been at the forefront in developing the design for the Lixhe plant.


9. What about the CO2 that LEILAC will capture?


The pilot is designed to address the engineering challenges for applying this new technology to the cement and lime industries. While the CO2 will be separated to prove that the technology can work, at this stage it is not planned to compress or liquefy the CO2 separated during the course of this project, due to the intermittent nature of the pilot test runs.


Given LEILAC will be testing a slipstream from the existing cement making process, the total CO2 emissions of the Lixhe plant will not increase.


10. Why the need for CCS?


In Paris in 2015 an agreement was made by all countries that global average temperature increases should be held to 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 °C above pre-industrial levels. However, the IPCC has stated that very few models could limit warming to 2 °C if carbon capture and storage (CCS) was not extensively used.


When making lime or cement CO2 is released as an intrinsic part of the production process, and cannot be avoided (for example by using renewable energy). As such, carbon capture is the only realistic means by which these industrial emissions can be further reduced to support EU to meet the 80% reduction target in 2050.


11. Is CCS technically mature?


The separate elements of capture, transport and storage of carbon dioxide have all been demonstrated, but integrating them into a complete CCS process and bringing costs down remains a challenge. There are two large projects currently working in Europe, at Sleipner (operating since 1996) and Snøhvit (operating since 2008), capturing and storing around 1.7 million tonnes of CO2.


However, the technology has not been applied to the cement nor lime industries, as traditional methods of capturing the CO2 are either too complex or expensive. New approaches are required, and LEILAC will provide an elegant, and cost effective way of doing so.


12. How much will carbon capture cost?


While traditional approaches are quite expensive, LEILAC aims to demonstrate that this new type of design will allow all of the process CO2 emissions to be captured without significant energy or capital penalty. The downstream processing costs of liquefying, transport and safe storage are not part of this project. These essential steps are not cement or lime specific and are developed in cross sectorial approaches with all CO2 emitting industries and utilities.


12b. What can CCU contribute in this development?

Captured CO2 can also be ‘used’. Such uses include CO2 for enhanced oil recovery, algae cultivation, mineral and residue carbonation, and food and beverage carbonation, and for fire extinguishers.


Though not able to replicate the scale of climate benefits of CCS, CCU can, to varying degrees lower the emissions of other products by providing a ‘recycled’ raw material.


13. If the ‘Direct Separation’ technology in LEILAC can capture 60% of the emissions, what about the rest?


When integrated into new plants, or retrofitted into existing plants, which are fired with biomass or waste using current best practice, by using ‘Direct Separation’ technology the total CO2 emissions would be reduced by more than 85% compared to conventional fossil fuel fired lime and cement plants, without significant operating issues, energy or capital penalty.


‘Direct Separation’ technology can also be used in conjunction with “end-of-pipe” carbon capture technologies that are currently being developed for the power, cement and lime industries to capture the remaining CO2.

14. What regulatory framework exists around CCS in Europe, ensuring that any stored CO2 is safe?


In 2009, the European CCS Directive was created to establish a legal framework to help ensure the environmentally sound geological storage of CO2. Its provisions cover the entire lifetime of geological storage sites in the European Union, as well as the capture and transport components of CCS, though these activities are mainly regulated through existing EU environmental legislation.

Such permanent storage is also the only way that many industries can decarbonise: for example CO2 is unavoidably released by the processing of cement meal, and CCS is the only way of managing these emissions. Norway has successfully stopped tonnes of CO2 from being emitted to the atmosphere by storing CO2 offshore for 22 years at Sleipner and then Snøhvit.

15. How have the cement and lime industries been addressing carbon reductions to date?


Both industries, despite being under intense global competition, have been actively investigating methods of reducing their CO2 emissions. One of the primary means to date has been through continuous investment in the most energy-efficient technologies and production processes.Biomass and waste substitution has already been achieved in large scale coal fired plants for cement, giving them up to 14% emissions reduction. The Direct Separation technology will enable the lime industry to achieve similar substitution for the first time, because impurities in the fuels will not contaminate the end product as it does in conventional kilns


They have also, in line with national or European supporting mechanisms, been coinvesting in other capture technologies, such as the new pilot plant at Brevik (which is applying a number of traditional capture techniques to the cement process for the very first time – which could be used in conjunction with LEILAC’s Direct Separation technology).


16. How is CCS treated under the EU’s Emissions Trading System?


The ETS provides the main incentive for CCS deployment. CO2 captured and safely stored according to the EU legal framework will be considered as not emitted under the ETS.

17. What will the outcome of the project be?

At the conclusion of the project a Cement and Lime industry CCS Roadmap will be developed. This Roadmap will be based on the outcomes of the LEILAC pilot’s construction and test, full-scale techno-economic study, Life Cycle Analysis, and retrofit report.


This Roadmap will explore, in depth, the timing and opportunities for the widespread roll out of this Direct Separation technology. This will be important in informing decision makers and industry of the viability of the widespread deployment of this technology as a means of accelerating the decarbonisation efforts of the industry, based on verified data. Using the European targets for emissions reduction, this should also provide tangible information regarding potential costs for the industry, which has had limited economic deep decarbonisation options until this point.



18. Is Fracking, and its risks, the same as CO2 storage?


No. They are opposite in their intent.  Hydraulic fracturing is the process of drilling and then pumping fluid into a shale formation to deliberately generate fractures or cracks, in order to release and extract natural gas (primarily methane). It is controversial, mainly due to possible leakage of methane to the atmosphere.  

In contrast CO2 storage would only take place in different location to fracking sites, and has the opposite objective: to permanently store CO2 and ensure it does not enter the atmosphere. As indicated in the European CO2 storage Directive, well developed, secure geomechanics and known fracture pressure are key elements of whether a CO2 storage site would ever be approved for use, and any CO2 storage site would be monitored for any unintended fracturing, and ensure there is no environmental impact nor release of CO2 to the atmosphere.  

19. Where can I find out more about LEILAC or CCS?


Feel free to contact us, or one of the other organisations listed in our Useful Links page.


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This project has received € 12m of funding from Horizon 2020 program for research and innovation of the European Union under the grant agreement No 654465.