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Low Emissions Intensity Lime and Cement

Periodic Reporting for period 3 - LEILAC (Low Emissions Intensity Lime and Cement)

Reporting period: 2018-07-01 to 2019-09-30

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, and its record-speed ratification by 175 countries, sets a clear global response to the threat of climate change. The 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 1.5 degrees Celsius, signals a clear intent to drastically reduce society’s carbon emissions.
Concrete is a highly durable material and vital to our society. Demand will go up due to the population growth and the trend to further urbanisation. However, cement production is CO2 intensive (8% of global CO2 emissions).
Over 60 percent of CO2 emissions are released directly and unavoidably from the processing of the raw materials.
In order to reach the EU’s emissions reductions targets by 2050, carbon capture and storage (CCS) will need to be applied to the majority of European cement plants, and LEILAC is uniquely placed to support Europe to achieve these targets in a timely, effective and efficient manner.

The principles of the technology
Calix’s Direct Separation 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 key technological/technical challenges
Applying this technology to a cement or lime plant requires research, development and careful engineering – as these materials need to be calcined at much higher temperatures and scale. The risks therefore being addressed by LEILAC include temperature scale up, fouling, calcination levels and throughput, future scale-up and integration issues, and costs.

The objectives of the pilot
The LEILAC project involves 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 unit until the end of 2020, during which it will undergo extensive testing 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 have a feed rate capacity of up to 240 tonnes per day of raw meal for cement production (the equivalent to 5% of a typical cement plant’s capacity) and 200 tonnes ground limestone.
The project is led by Calix, the company behind the Direct Separation technology. Providing funding, guidance and technical input, the project’s industrial partners are HeidelbergCement, CEMEX Research Group AG, Tarmac, Solvay and Lhoist. ECN (part of TNO) is undertaking key research into the primary areas of risk: providing steel analysis, corrosion and fouling testing and analysis. Imperial College London is undertaking materials analysis, kinetics modelling and computational fluid dynamics (CFD) modelling. Process Systems Enterprise is carrying out the modelling and techno-economic analysis of the technology, and Quantis is looking at Life Cycle Analysis. The Carbon Trust is responsible for public engagement. It is supported by an External Advisory Board formed by CEMBUREAU, ECRA, EuLA, and GCCA.

LEILAC has now undertaken three years of 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.

The project has followed engineering stage gates to ensure that the pilot was technically viable; would fulfil the operational objectives of the overall project; and that it could be built within the cost constraints of the budget. The past three years has seen a thorough engineering exercise for the pilot. There has been a stage-gate feasibility, front-end engineering, and then design phase. Through each phase, the project has reduced risk, refined the design, and undertaken systematic safety assessments. Following the final Financial Investment Decision, the pilot entered construction. Led by HeidelbergCement and supported by Calix, the construction 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, initial trials of the LEILAC pilot are extremely promising and that 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.
The LEILAC pilot unit will undergo extensive testing in a standard operating environment. The research on the process demands and performance aims to demonstrate that the technology works sufficiently to begin scale-up planning 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.

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 testing, full-scale techno-economic study, Life Cycle Analysis, and retrofit report.
Increasing interest 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