LafargeHolcim in the US (LafargeHolcim) and CO2 capture technology firm Svante are developing a full-scale CO2 capture and storage solution at the Holcim Portland plant in Florence, Colorado, US. Global Cement found out more about the project from LafargeHolcim’s Derick Dreyer and Svante’s Claude Letourneau, plus how the parties are preparing for the future carbon economy...
Global Cement (GC): Please could you outline the origins of Svante?
Claude Letourneau (CL): Svante traces its history back to 2007, when it was established as Inventys Thermal Technologies. The company’s four founders wanted to adapt the technology of an earlier firm that selectively purified hydrogen for use in fuel cells. They switched the gas target to CO2 from flue gases. Inventys then scaled up this technology with a range of industrial partners. The company was renamed Svante in 2019.
GC: How does its technology work?
CL: Svante has developed what is essentially an industrial filter for CO2 that uses very high surface area sorbents. This can be activated carbon, amine-doped silica or, more recently, a metal-organic framework (MOF) that we have developed, which has an exceedingly high surface area. The MOF has a surface area of 7000m2/g. That’s metres, not centimetres!
The sorbent is arranged in a structured laminate architecture that has an area of more than 2500m2/g. This provides a parallel passage flow with minimum pressure drop in order to allow very fast diffusion of CO2 into the sorbent.
GC: How is this used in an industrial context?
CL: The process extracts CO2 from process flue gas using a temperature swing. A feed with ~16% CO2 is fed at a relatively low temperature to the top of a circular platform that contains the sorbent and rotates at 1rpm. The sorbent rapidly binds around 90% of the CO2 selectively in preference over the dominant gas, N2. Then, as the platform rotates, the CO2-rich sorbent reaches the other side of the system. Here, high-temperature steam removes the CO2 from the sorbent. The sorbent then continues its journey back to the other side of the system via a cooling zone. It then goes back to the adsorption zone to bind more CO2 and the process repeats.
The separation of the captured CO2 from the steam is then relatively straightforward compared to dealing with a stream full of N2, NOx, SO2. These all pass to the main stack.
It was clear relatively early on that this process could be extremely useful for the cement sector, which is hard-to-abate. It represents the biggest potential user for this technology going forward.
GC: You said that 90% of the CO2 is captured by the sorbent. Does that mean 10% goes to the stack?
CL: At present this would go to the stack, but Svante has another project with Climeworks that is looking to capture this CO2.
GC: Could you loop the scrub-filter gas back to the top of the filter?
CL: No, as the scrub-filter gas is only 1.5 - 2.0% CO2 and it would start to dilute the incoming gas flow. This would reduce the efficiency of the separation process. Remember that we are using the entire exhaust of the cement plant, not a slip-stream.
MOF Matters
Metal organic frameworks (MOF) are a class of chemical compounds characterised by metal centres that are linked by multiple carbon-based molecules known as ligands. Many MOFs have voids large enough to host solvent molecules or small gas molecules. By tuning the length of the ligands, the voids can be made more likely to favour a target molecule, e.g., CO2, rather than other molecules, even if the undesired molecules are more abundant than the target ones.
GC: How long did it take to develop the MOF sorbent?
CL: The MOF, known as MOF CALF-20, has been developed by Professor George Shimizu’s lab at the University of Calgary since 2014. We knew relatively early on that it was what we needed for our process, but the cost was too high. In 2018, the researchers found a different way to make it, which lowered the production cost to US$20 - 30/kg. Svante negotiated an exclusive license to use the material and scaled up the production process.
GC: How much MOF CALF-20 is for the Portland project?
CL: We need 1t of MOF CALF-20 per 30t/day of CO2 to be captured, which translates to 220t of material. This is not a small machine. We are working now with industrial partners to develop MOF and filter production plants. These will be sizeable undertakings that lead to an entirely new industry.
GC: Cement flue gas streams have many components. Does this present the MOF filter with any stumbling blocks?
CL: Traditionally treating cement plant flue gases with sorbents has been very difficult due to the presence of SO2, NOx and O2. All of these kill a wide range of sorbents, rendering them ineffective. The successful development of MOF CALF-20, a chemically- and thermally-stable structure, gets around this issue.
GC: How long does the MOF filter last?
CL: The laminated MOF filters will operate for 3 - 5 years before they need to be changed. The replacement cost of the filter is US$2-3/t of CO2 on an annual basis. This is in stark contrast to the amine approach where there is rapid degradation. You have to top up the amine every single day.
The CO2MENT Project
GC: Svante and LafargeHolcim recently announced some developments in their joint CO2MENT project. Can you outline its origins and next steps?
CL: The CO2MENT project is a large undertaking involving Svante, LafargeHolcim and a number of industrial partners. It aims to capture 2Mt/yr of CO2 from the Holcim US plant in Florence, Colorado, US.
Derick Dreyer (DD): The current partners are LafargeHolcim, which provides the site and the CO2, Svante, which provides its CCS technology, Occidental Low Carbon Ventures, which contributes its CO2 transport and storage expertise, and Total, which is a funding partner and observer. The United States Department of Energy’s National Energy Technology Laboratory (DOE-NETL) recently provided US$1.5m of funds.
CL: Svante is currently working with LafargeHolcim at its Richmond plant in British Columbia, Canada, which is the first time the MOF sorbent has been used in the field. (Previous Svante plants have used amine-doped silica). The construction of a 1t/day trial CCS plant is ongoing and initial results from the gas separation trials are very promising.
GC: What are the drivers for the project from LafargeHolcim’s perspective?
DD: The ultimate driver is sustainability, which has always been a major priority for LafargeHolcim. At the Climate Week NYC in September 2020, the group committed to net-zero CO2 emissions by 2050 and it is the first cement producer to commit to meeting the objectives laid out by the 1.5°C scenario in the Paris Climate Agreement.
While we have taken many steps to reduce our CO2 intensity globally so far, we recognise that CCS is going to be a major part of the solution for LafargeHolcim’s 2050 target, as well as its interim target to reduce specific CO2 emissions by 40% compared to the 1990 baseline by 2030. The CO2MENT project is a big part of that.
GC: How will the project develop from this point?
DD: We ran a scoping study from January 2020 to June 2020, which involved all of the partners. Now we are in the pre-feasibility and feasibility stage, which will last until February 2022. Then we will move into a Front End Engineering Design (FEED) study and design stage so that a US$300m-plus investment can be justified. That will take another 18 months.
We hope to be shovel-ready by mid 2023. That’s how long it takes to develop such projects. The project should be up-and running in 2024 or 2025.
GC: Why was the Holcim Portland plant selected?
DD: As we looked for a suitable site for a full-scale installation, the US provides some unique advantages. This is due to the 45Q tax credit, which provides US$50/t for sequestration and US$35/t for CO2 captured and used for enhanced oil recovery (EOR) This is a major incentive that is driving a lot of innovation in the US.
As far as the Holcim Portland plant goes, it is a modern facility with a 5-stage preheater and calciner that was commissioned in 2000. It has a good future ahead of it and, at more than 5000t/day, it is also fairly large. Crucially, it is the closest of LafargeHolcim’s US plants to an existing CO2 pipeline, less than 100km, as well as potential sequestration sites in the Permian Basin.
GC: How much space will the CCS plant use?
CL: This is an end of the pipe solution and is a lot smaller than some other proposed solutions for CCS. However, the process does require auxiliary fans and a hot steam generator, so it will take up some space. However, we expect this to not be prohibitive.
GC: Does this extra equipment eat into the green credentials of the CCS process?
CL: The steam generator requires fuel, but the CO2 generated will be fed to the CSS unit. The fans will use renewable energy, most likely solar in the case of the Holcim Portland plant. The CCS plant will have a capacity of 2Mt/yr so these emissions can be accommodated.
GC: How do the economics of the process stack up?
CL: We anticipate that this approach will be less expensive than other CCS options. Take for example the well-publicised Norwegian project, which will use amine-based liquid solvent. This will cost US$187m of capital investment to capture and liquify 0.4Mt/yr of CO2. This works out at a unit investment cost of US$467/yr/t of CO2.
In contrast, the CO2MENT project at Florence will cost US$325m to capture and compress 2.0Mt/yr of CO2. The unit investment cost is US$162/yr/t. That’s 65% lower! We are working to a capture cost of US$50/t of CO2 removed because that’s what comes from the 45Q tax credit. The Norwegian government, however, has chosen to subsidise the project, which works out in the US$80 - 90/t range. The country wants to develop its CCS capabilities, which it sees as an investment in the future.
Beyond the Portland plant
GC: How applicable is the cement plant to other plants in the US, and further afield?
CL: The map (see images) shows the location of existing CO2 pipelines and cement plants in the US. There are clearly a number of candidates that could be easily connected to the existing network. At the same time, we can expect the network to expand over the next 5 - 10 years, so there are clearly many opportunities.
GC: Where will the captured CO2 be stored?
DD: There are two options. Most of the existing pipelines take natural CO2 from the ground and pipe it into a depleted oil reservoir for enhanced oil recovery (EOR). Instead, the natural CO2 could be left in the ground and the captured CO2 used in EOR. Alternatively we could pump the CO2 into a natural saline reservoir. This locks in the CO2 irreversibly. This is the approach taken by the Norwegian project, a massive investment that will take waste CO2 from industrial plants all over northern Europe.
GC: What is the minimum level of CO2 capture that LafargeHolcim would view as a success?
DD: Ultimately, we would not be considering a 2Mt/yr CCS facility if we didn’t think it was feasible. Indeed, by 2030 LafargeHolcim has committed to operating at least one cement plant meeting the net zero commitment. I honestly don’t see why it cannot be the Holcim Portland plant. That said, every step along the way is a success because it informs the group and its partners about the next steps and opportunities in our continued work to reduce emissions.
Further into the future, I think the Portland site can act as an example to other LafargeHolcim plants, as well as those of other producers. Each plant has unique geology and CO2 pipelines. It may be that not all plants can do this, but we don’t see this as an isolated case going forward.
Markets and the Future
GC: What is the best way to incentivise investment in CCS?
CL: There are different government-led approaches in different jurisdictions and they are all welcome. However, what we are seeing now, with company after company committing to net-zero CO2, is a voluntary price on CO2 emissions. Take Microsoft, which directly emits around 40Mt/yr of CO2, as much as 20 Florence plants. It is now committed to eliminating those emissions and is willing to pay up to US$100/t to do so. This money will feed into the development and deployment of large-scale CCS.
I think we are five years away from seeing the implications of the commitments we have made over the past 12 months. The industrial players are creating a market where demand for CCS technology will vastly outstrip the availability. We have cracked the technology side, now we need to work out how to administer real-world, full-scale CCS projects that can provide a return-on-investment.
GC: What does the longer term future hold for CO2 prices?
CL: I believe that the cost of CO2 emissions will plateau at around US$150/t, globally. This will be due to Border Carbon Adjustment mechanisms (BCA) that take into account the cost of the embodied CO2 when a product crosses a border. The EU is in the process of developing this at the moment with reference to its Emissions Trading Scheme (ETS). This approach across multiple jurisdictions will lead to a full CO2 market.
Of course, it is impossible for LafargeHolcim and other producers to take the full burden of the price increase. We need each part of society to take a small piece of the cost increase.
GC: Where will the Portland plant stand in the pantheon of CCS projects?
DD: There has been a great acceleration in CCS research in recent years in the cement sector and elsewhere. However, if we look at full-scale CCS in the cement sector, references are still lacking. We hope that ours will be the first and, as the largest announced to date, that it gains recognition as a major milestone in CCS technology in the coming years.
To conclude, LafargeHolcim has set some ambitious goals and we intend to achieve them. As our CEO Jan Jenisch says, “We need solutions that work for people and the planet.” I see no reason why the cement industry can’t have a fantastic future in which we meet both our sustainability and business goals.
GC: Thank you for your time today gentlemen.
CL/DD: You are very welcome indeed.