4th Global FutureCem Conference on cement industry decarbonisation
6 - 7 December 2023 - Brussels, Belgium
The 4th Global FutureCem Conference on cement industry decarbonisation has taken place in Brussels, with delegates from around the world. The majority of delegates felt that their companies would substantially reduce their carbon emissions as a result of attending the event.
Ioannis Retsoulis of the Joint Research Center of the European Commission gave an opening overview of the current status of the Industrial Emissions Directive (IED). As Inoannis says, "The IED is currently being revised, including more effective legislation, which will boost green innovation and increase decarbonisation. He furthermore elaborated on the INCITE (INnovation Centre for Industrial Transformation and Emissions) concept. INCITE as an innovation centre, having a global vision, aims to be the central point of reference for identifying and evaluating the environmental performance of emerging technologies in Europe and beyond. Early technology front-runners will be rewarded with more lenient permitting, whilst outputs from INCITE can encourage financing of emerging environmental technologies and foster competitiveness. He emphasized that working hand in hand with the cement industry and all relevant stakeholders is important in order to unlock INCITE's full potential, and that a launch event for INCITE is provisionally planned in Spring 2024 in Seville, Spain."
Chris Erickson of Climate Earth spoke about the use of automatically-created Environmental Product Declarations (EPDs), for both cement and concrete. EPDs are 3rd party verified international standardised reports used to report assured environmental performance about products in particular product categories such as cement, or concrete, allowing comparisons between products. The information that is gathered for EPDs is put into a database, allowing ‘instant’ generation of machine-readable EPDs for cement blends and concrete mixes. In Europe, the same data can be used to create country-specific EPDs, since requirements across the EU vary from country to country. The cost of each EPD is also much reduced.
Dan Maleski of Redshaw Advisors outlined how the new CBAM scheme in the EU and how it affects the European (and global) cement industry. Dan presented a slew of forecasts for the cost of emitting a tonne of CO2 in the EU, suggesting that it will be Euro150 in 2030, and Euro225 by 2035. CBAM will impose a carbon price on imported goods, considering their embedded carbon, akin to the EU ETS (and with the same cost). He pointed out that the CBAM scheme is exceptionally bureaucratically cumbersome. The transition period started in October 2023, to allow industry to learn how to use the scheme. Full compliance will start in December 2025. Non-compliance may eventually result in revocation of importation rights. The phase-in of the CBAM scheme will be synchronous with the phase-out of free allocations under the EU ETS. Dan said that importers of clinker and cement will find their margins under pressure. However, countries can establish their own ETS schemes, pay their carbon taxes to their own country exchequer and import into the EU CBAM tax- free. There may eventually be a CBAM export rebate, depending upon the stance of the WTO.
Professor Johann Plank of the Technical University of Munich next spoke on decarbonisation strategies of the cement and concrete industries. Each year mankind releases 41Bt of CO2, although the biosphere absorbs 13Bt, and the oceans 10Bt, leaving 18Bt of additional CO2 in the atmosphere, which should be eliminated to achieve climate net zero. The cement industry should be aiming at an average of not more than 455kg CO2/t cement in order to ‘do its bit.’ Decarbonisation of limestone produces around 65% of emissions from ‘traditionally-produced’ OPC, fuels provide 20% and grinding produces another 15%. Oxyfuel firing uses near pure O2, and allows easier CO2 capture. Carbon capture can be achieved using amine scrubbing (‘the BASF process’), which can be made more efficient by using catalysts to reduce the splitting or cleaning temperature of the amines; by using membrane technology; by using cryogenics and by other means. The Leilac process of indirect limestone heating and decarbonisation can also be used to create a CO2 rich exhaust stream (see also below). Captured carbon dioxide may be injected into offshore reservoirs in the form of a supercritical liquid. Around 200 CCS projects are already in operation, with more than 40 under construction, while Norway, the USA and Canada are very active in this area. Prof Plank pointed out that normal oilwell cements are not resistant to supercritical CO2, and new cements will be required to cap these CO2 injection wells. Johann reminded delegates that the global warming potential of concrete - even made with OPC - is relatively low, perhaps 310kg CO2 per cubic meter. If it is made with blended cements, using slag , activated clays and ash, then concrete can even be made ‘net zero.’ Alkali activators (Na2SO4, Na2CO3, Na2SiO2, NaOH) may be needed to improve early strength in slag-based cements, while superplasticisers may be required with low water-to-binder ratios to allow workability. New activators and admixtures are currently being developed for the new low-clinker binder systems. He pointed out that LC3 cement (with 50% clinker) and a 550 - 600kg/t CO2 emission is not climate neutral and the use of superplasticers and accelerators may be required to achieve on-site workability. In China, the clinker factor is around 70%,with the remainder generally being slag and/or limestone, while huge programmes are underway to use mining tailings and ash as supplementary cementitious materials (SCMs). The Chinese cement industry has a production capacity of over 2Bt, but demand in 2024 is expected to be only around 1Bt (leading to a 'saving' of perhaps 800Mt of CO2 emissions compared to previous years).
Fabrice Fayola, CEO of Surschiste and president of ECOBA, the European coal combustion products association, spoke about the position of ash in Europe. 123Mt of ash is used each year in Europe, even while the production of coal combustion products (CCPs) is steadily decreasing. Many countries are now using ash from stockpiles, particularly in countries that now have no fresh CCP production. A variety of EU standards allow the use of ash in cement and concrete, and fly ash is now covered by EPDs, typically with 50 - 100kg CO2/t of embedded emissions.
Lawrie Evans of EmCem Ltd next stated that the last thing that the cement industry needs right now is clinker. The clinker factor in Europe was 0.95 until around 1970, at which point it reduced over a couple of decades to around 0.7, using SCMs. Globally, it has next to no possibility of reducing to its target of 0.45 by 2030. Lawrie pointed out that significant strength gains can be gained by optimising the particle size distribution. Additionally, cement particles over 32microns are effectively unreactive (and the CO2 emitted during their production was for no cementitious effect), since articles only hydrate to a depth of around 5 microns - and even particles larger than 10 microns have unreacted cement cores. He suggested that intergrinding of limestone with clinker results in under-ground (and under-reactive) coarser clinker particles. Limestone should be separately ground from clinker in order to optimise clinker performance. He said that it was time for cement to be environmentally rated - like refrigerators or homes - on a simple F to A scale.
Niall O’Hare from Ecocem next spoke about high-filler low-water cements. CCUS on its own will not be enough to decarbonise the cement industry, due to both technical and economic issues. Ecocem’s ACT cement is composed of 50% limestone filler, 30% SCMs and only 20% clinker, which has a carbon footprint of 180kg CO2/cement. The company has optimised particle size distribution and has used additive technology to improve or surpass the workability of traditional cements. Around 330kg of ACT is used for each cubic meter of concrete, with performance equal to traditional cement.
Mathieu Pépin of Stepan Europe next spoke about how to unlock the power of graphene using aqueous fluid suspensions. Graphene adds mechanical strength, reduces water permeability and adds sulphate resistance to concrete. However, graphene is an insoluble fine powder and it is difficult to disperse in aqueous mixtures. Stepan has a patent-pending suspension system that allows temperature-stable high aqueous concentrations of graphene, with a user-friendly viscosity and which is stable for up to six months. Just a 0.01% loading of graphene can significantly improve concrete performance, requiring only a 0.003% wt/wt addition of the Stepan suspension additive.
Jagabandhu Kole of JSW Cement gave the final presentation on the first day, on durable low carbon cement (DLCC) with only 5% clinker. JSW’s mix uses 80 - 85% GGBFS, 10 - 15% anhydrous gypsum and 5% OPC clinker, along with some additives. Performance of DLCC is reduced compared to PPC and PSC, but is still higher than required for the particular concrete grade. DLCC has low water and chloride ion permeability, making it well-suited for marine environments. Dr Kole stated that cement demand in India is increasing at around 12% per year: JSW Cement has a target of becoming ‘close to net-zero’ by 2070.
At the end of the first day of the conference, delegates enjoyed a convivial dinner and a fun ‘pub quiz.’
Second Day
Commencing the second day of the conference, Dirk Schlemper of INFORM GmbH outlined how AI can reduce costs and CO2 emissions from building materials logistics. He pointed out that a 300km round trip for a cement truck will produce around 560kg of CO2 - as much as a tonne of cement. This offers a juicy target for optimisation. Efficient logistics can also help to gain points towards sustainability certifications. Electric vehicles add further complications (range, recharging time, charging infrastructure, temperatures and elevation profiles) to logistics calculations, but the software can cope - easily.
Koen Coppenholle, CEO of Cembureau, pointed out that the new ‘big idea’ for the EU, after its single market project of the last 40 years, is the EU ‘Green Deal.’ Part of that is the CBAM, as well as a new Innovation Fund. Cembureau’s Road Map outlines many levers (‘The 5C approach’) for decarbonisation, and Koen said that all levers will be needed - with CCS making up perhaps 40% of the solution. “Long term investment cycles (30 - 35 years) mean that 2050 is practically just around the corner.” The lack of renewable energy and inadequate planning for the future will leave the EU uncompetitive and unprepared for an electrified future, with demand for electricity doubled or tripled. The biogenic component of alternative fuels is becoming more important, since biomass is zero-rated for CO2 emissions - contrary to fossil-based AF. The Net Zero Industry Act, NZIA, will regulate the CCS industry in the EU, while giving long-term certainty to sector participants. The Innovation Fund is primarily for demonstration-level projects at technological readiness levels (TRL) 7 - 8, with cement sector projects well represented. The permanence or otherwise of the ‘use’ part of CCUS is being actively debated at the moment - for example mineralisation would be permanent, but would manufacture of a plastic be permanent sequestration of cement industry CO2?
Luc Rudowski from thyssenkrupp Polysius and Hendrik Möller of Schwenk Zement next spoke about a new approach to valorisation of clay through mechano-chemistry. Luc stated that calcined clays are becoming a reality throughout the world, particularly in west Africa, since clinker imports are expensive. The tkP mechano-chemically activated (‘meca’) clay approach goes beyond grinding, although grinding is the first step during the ‘Rittinger stage,’ where the lower size limit is reached. The second step is an aggregation and activation stage where crystal structures are broken down: the higher the level of amorphisation, the higher the level of energy imparted and stored in the meca-clay. The third step is an (re-)agglomeration stage and the fourth stage is the application stage, with particle disintegration and hydration. In the second stage, which is the start of mechano-chemical activation, the tkP ‘Booster mill’ or Charger - a dry agitated bead milling technology - is used to maximise the surface energy of the clays, using the minimum electrical energy input. The electrical consumption of the process is higher than for normal calcined clay (450kWh/t vs 66kWh/t) , but the thermal input is lower (174kWh/t vs 609kWh/t), giving a modestly lower energy consumption on average (624kWh/t vs 675kWh/t), but with 70% lower thermal CO2 emissions. The strength of mortars formed from meca-clays is higher than for clinker - even with clays with low kaolinite content of only around 5%. The meca-clays produced have more rounded morphologies, which aid in mortar and concrete workability, while reducing water demand. Due to the low processing temperatures, even calcareous clays will not produce CO2 emissions. A demo-scale plant will be build at the Schwenk Allmendingen plant.
Pierre Landgraf from the Technical University Freiberg next spoke on mechanical comminution and electrodynamic fragmentation of concrete rubble in the UpCement project. The aim of the project was to separate hardened cement paste from old concrete rubble, and to reactivate the recovered paste at low temperatures. Jaw, cone and impact crushers are used for comminution, followed by electrodynamic fragmentation (EDF). An electric current is passed through a water tank containing ground rubble - the current preferentially passes around constituent particles in the concrete and disaggregates the concrete at the grain boundaries. With finer comminution and separation, the fraction of cement paste in the samples increases. Pierre concluded that further investigations must continue.
Tom Hills from Leilac Ltd came to the podium to give delegates an update on developments at the company, after the installation of the original Leilac 1 project at the Lixhe plant in Belgium, which had a single tube. The four-tube single module Leilac 2 installation in Hannover has a carbon capture capacity of 100,000t/year. Leilac uses an externally-heated tube down which the raw materials are dropped. The tube radiates heat into the raw materials, which are thus calcined. The process gas is then nearly-pure (98%) CO2 which can subsequently be captured. The Leilac vessel would replace the preheater and precalciner in a traditional plant. In the future, more four-tube modules would be added to scale processing capacity. The Leilac 2 project is exploring the use of solid alternative fuel, and also uses vent and tertiary air streams. Tom suggested that the cost of the process will be around Euro33/t of CO2 avoided, with capital cost for a 2.4Mt unit at around Euro100m. 70% of the cost of using Leilac are capital repayments and the operation of the CO2 purification and compression unit. Fuel costs are reduced compared to a traditional process, and maintenance is modest. Electricity or zero-carbon fuels are options for the future, for higher avoidance rates. Post-combustion capture (PCC) fuel CO2 capture may be achieved with amines, with the process powered using waste heat from the cement plant, bringing the cost for CO2 avoidance to Euro39/t CO2. Tom suggested that one large Leilac plant would need to be built every week from now until 2050 to fully decarbonise the world’s cement industry. Leilac Ltd is also exploring direct air capture (DAC) options.
Jerome Friler next gave details of a proposed fully-decarbonised cement plant using hydrogen, in Mauritania. Several large infrastructure projects are planned in the vicinity of Nouadibhou, requiring large quantities of cement. A new plant is planned, but lenders were not interested - until the plans were modified for it to become a fully decarbonised plant. The plant will produce LC3 cement, using green hydrogen produced using solar and wind electricity from a nearby 100MW wind farm, and a to-be-built 55MW solar farm. The green H2 plant will produce at a rate of 23t/day, which can be fed to a turbine to produce electricity for wind and solar-free days. The plant will be fired using imported alternative fuels. The price of cement in Mauritania is currently $160/t, and the plant will reduce expensive imports. The plan is to create synthetic methanol with any captured CO2.
Victor Smith from CM Biomass gave an overview of the global wood pellet market and its potential benefits for the cement industry. Major inflows of wood pellets into Europe occur from the US (8Mt/y), Canada (1.7Mt/y), southeast Asia (1.1Mt/y) and other sources including South America (0.7Mt/y). German cement industry coal use is the equivalent of the use of 5Mt of wood pellets, so that there is a huge potential market for biomass-based pellets. In fact, other types of biomass are available apart from wood, including cashew shells, palm kernel shells, bagasse pellets, olive pits, straw pellets, sunflower husk pellets and coconut pellets, with a variety of net calorific values and ash contents, sourced from around the world. Victor suggested that the use of wood pellets saves around 90% of the CO2 emissions compared to coal, after calculating processing and shipping emissions.
In the first of a trio of papers on CCUS, Nicolas Renard from CMS spoke about carbon capture economics with membranes. “We can’t build a nuclear power plant just in order to drive a carbon capture system,” was a comment from one industrial sector, with a strong message coming from others that low energy carbon capture is a must. Membranes selectively allow CO2 to pass through, with relatively low pressure loss, and have been used for this purpose for decades already, for transformer oil degassing, for olefins paraffin separation, and for CO2 removal from natural gas. The solution from CMS is modular and containerised, and the membranes are chemically resistant. Nic suggested that a realistic estimate of cost would be Euro85/t of CO2 captured, delivering pipeline-transport-quality carbon dioxide at a cost ‘at least 25% better than MEA (amine capture).’ The costs of capture would reduce with electricity at less than $0.06/kWh.
Thomas Lamare, previously of Holcim and now with Chovet, spoke on the ins and outs of integrating a full-scale carbon capture unit in an existing cement plant. In general, electricity demand for carbon capture will be much higher than for ‘plain’ cement production. Thomas gave the example of an installation of a carbon capture system at a Lhoist lime plant in France. He concluded that the technological challenges have largely been surmounted, but that the economics may still be against widespread adoption, today at least. Every plant will be unique, and sequestration will not always be possible. In this case, there will be a 50km pipeline to Dunkerque, from where the CO2 can be further transported for sequestration.
Xavier d’Hubert of XDH-energy gave a final round-up of the challenges and opportunities that CCUS offers to the cement industry. He pointed out that the production process must first of all be fully optimised. Once optimised, other options can be used to reduce the embodied carbon in the produced cement, such as alternative fuels, the use of slag and other SCMs, and the use of renewable electrification, prior to considering CO2 capture. He reiterated that the energy requirement for an amine-based CC scheme will be colossal, and that WHR may supply a portion of that energy. Gas streams into carbon capture units, independent of the capture technology, will be required to be clean, dust-free, dry, and cool. Achieving this is not free. Ceramic catalytic filters (‘candles’) might be an option for gas conditioning in the future. Adsorption (using MOFs), absorption (for example using amines), cryogenics and membranes are distinct carbon capture options, but hybrid systems are also possible. Future technology choices are under active consideration by many cement producers and other industry sectors.
Delegates voted for their favourite presentations at the end of the conference: Niall O’hare from Ecocem was third, Johann Plank from TU Munich was runner-up, and Luc Rudowski from thyssenkrupp Polysius and Hendrik Möller of Schwenk Zement were in first place with their paper on meca-clays. Delegates strongly praised the 4th Global FutureCem Conference for its smooth organisation, excellent networking opportunities and for its technical content.
