Displaying items by tag: Research

China: China Building Materials Academy has patented a new 3D printing method which uses short rebars to reinforce printed layers. The developer says that this will enable builders to ensure structural strength without the disruption caused to 3D printing by the long rebars of conventional building skeletons.

China Building Materials Academy said that an 'inverted U-shaped or inverted L-shaped short rebar is vertically inserted into the cement slurry layer, wherein the bending mechanism comprises two bending members, separately disposed on two sides of a clamp.'

India: Research by the Indian Institute of Technology – Madras (IIT Madras) has concluded that limestone calcined clay cement (LC3) production emits 40% less CO₂ than ordinary Portland cement (OPC) production, and is 20% less energy intensive. United News of India has reported that the Switzerland-based Swiss Agency for Development and Cooperation supported the study.

UK: Breedon Group, together with Australia-based First Graphene, Morgan Sindall Construction & Infrastructure and the University of Manchester, is developing a new reduced-CO₂ graphene-enhanced cement. The consortium is currently formulating the cement using varying doses of First Graphene’s PureGRAPH graphene-enhanced grinding aid. The project received a research grant from the UK government earlier in 2022. First Graphene says that the study involves one of the largest commercial trials of its kind to date globally. It is simultaneously collaborating on another similar trial with a Europe-based speciality chemicals producer.

On 29 September 2022, First Graphene launched its latest range of graphene-enhanced cement grinding aids and concrete additives. These join recent launches PureGRAPH AM, an admixture developed in collaboration with South Africa-based Nanoproof/Glade Chemicals, and HexMortar, a dry mortar mix which will be distributed by New Zealand-based GtM Action.

First Graphene says that its cement and concrete segment’s order pipeline totals US$113m in value. Managing director and chief executive officer Michael Bell said “It is pleasing to see our efforts, and those of our collaboration partners, coming to fruition at a commercial scale. One of the primary drivers for the adoption of graphene solutions in this segment is the reduction of CO₂ emissions. We’re seeing considerable benefits both in the immediate reductions that can be achieved through the use of graphene-enhanced grinding aids, as well as the potential reductions in concrete usage because of the enhanced physical properties these products provide.” Bell concluded “Working with industry-focused partners such as Nanoproof/Glade Chemicals, GtM Action, Breedon Cement and Fosroc opens the way to an estimated addressable market of more than 12,000t of PureGRAPH across the medium to long term.”

UK: Clean Energy Ministerial CCUS (CEM CCUS) and the Global Cement and Concrete Association (GCCA) have announced a new partnership aimed at scaling up the deployment of carbon capture technologies in global cement and concrete production over the 10-year period up to 2033. The partners will explore incentives, policy frameworks and finance solutions that can best facilitate industrial-scale CCUS projects. Additionally, they will seek to ensure the long-term development of CCUS via technological developments.

CEM CCUS Norway initiative co-lead Henriette Nesheim said “This is a great opportunity to work together with a vitally important industry. In Norway we are already building our first cement CCS project in Brevik, and we look forward to sharing the experience with others.”

Denmark: FLSmidth says it will lead CO₂Valorize, a new consortium intended to develop and deploy carbonation technologies in the cement industry. The group will receive Euro2m from the Marie Skłodowska-Curie Doctoral Networks and is supported by the European Commission’s Horizon Europe initiative. The expected commercial and technical outcomes of the consortium include a full flow sheet of the carbonation process line, the techno-economic analysis of various technology and materials options, and the optimisation of FLSmidth's proprietary reactors. The project is also intended to be a key part of FLSmidth MissionZero programme.

Burcin Temel McKenna, Head of Green Cement Solutions Development at FLSmidth, said “We have been granted a unique opportunity to revolutionise the cement industry at a time of extreme urgency”. He added, “On-site carbon capture and utilisation projects will be a quicker and more economically viable way forward for in cement plants.”

The consortium includes the following partners: Norwegian University of Science and Technology; Karlsruhe Institute of Technology; HZDR Innovation with Helmholtz-Zentrum Dresden-Rossendorf and Technische Universität Dresden; Technical University of Denmark; University of Padova; Siemens Process Systems Engineering; and the Slovakia-based cement producer Cemmac. The partners will support eight fully funded PhD students conducting research into the characterisation and kinetics of carbonated materials and optimisation of the carbonation process. They will also explore the commercial opportunities for mineral carbonation. The focus will be on the carbonation of calcium-, aluminium-, and magnesium-silicates as well as cement derivatives, slag, fly ash, recycled concrete fines and mine tailings.

US: A team from Washington State University (WSU) and Pacific Northwest National Laboratory has successfully used waste crustacean shells in the production of concrete. ZME Science News has reported that the materials consist of calcium carbonate and 20 – 30% chitin, a nanoparticle biopolymer. When used as an additive in concrete production, the shells increase the set product’s compressive strength by 12% and its flexural strength by 40%. The team is now developing a methodology for the industrial-scale production of shell-based additives.

WSU researcher Professor Michael Wolcott said “Those are very significant numbers. If you can reduce the amount that you use and get the same mechanical function or structural function and double its lifetime, then you’re able to significantly reduce the carbon emissions of the built environment.”

US: A team from the University of Colorado Boulder (UCB) has developed a carbon-neutral alternative cement from biogenic limestone. The limestone comes from farmed cocolitophores, which capture CO₂ as they grow.

The UCB scientists collaborated with colleagues from the University of Carolina at Wilmington and the National Renewable Energy Laboratory on the project. Their work has received US$3.2m in US Department of Energy funding.

This news story has been corrected to include the correct name of the University of Colorado Boulder

UK: Karbonite UK has developed a new supplementary cementitious material consisting of mineral feedstock, geopolymers and waste biomass. The process also involves CO₂ sequestration and liquid-infused CO₂ absorption within the mineral structure. The material, called Karbonite, is activated at 750 – 850°C, releasing water, which is captured for recycling. Its CO2 emissions are 2.7kg/t, according to Karbonite UK. The developer says that Karbonite ground with 50% clinker yields a cement of equal compressive strength to ordinary Portland cement (OPC).

Karbonite UK is currently preparing a final report on the product for a major cement producer.

Managing director Rajeev Sood said “Karbonite offers a wealth of potential to an industry targeting net zero. We are excited to talk to cement and concrete producers about how they could integrate Karbonite technology into their existing process.”

France: Holcim France has announced its successful industrial-scale production of the world's first 100% recycled clinker. The La Tribune newspaper has reported that the company's Altkirch, Alsace, cement plant produced the clinker. Holcim France chief executive officer Francois Petry said that the plant's team collaborated with researchers at the Holcim Innovation Center to develop a recipe that incorporated multiple waste streams, including mineral wastes and wood ash. The producer says that most of the waste materials were locally sourced.

Coolbrook has been in the news recently with collaboration deals struck with Cemex and UltraTech Cement. First the Finland-based company officially launched its Roto Dynamic Heater (RDH) technology with a memorandum of understanding signed with Cemex in May 2022. Then, this week, it signed a similar agreement with UltraTech Cement.

The specifics of either agreement are unknown but the target is clearly to build an industrial pilot of an electric kiln – or something like it - at a cement plant. Coolbrook says it has run a pilot of its RDH technology in Finland. Further tests are now scheduled to continue for two years starting from September 2022 at the Brightlands Chemelot Campus at Geleen in the Netherlands. Commercial scale demonstrations are scheduled from 2022 with the hope of commercial use from 2024. Links with Cemex and UltraTech Cement seem to suggest progress. At the same time Coolbrook will be testing its RotoDynamic Reactor (RDR) technology, which promises to electrify the steam cracking process used in plastic manufacturing.

Publically available details on the RDH technology are light. In its promotional material Coolbrook says that it can achieve process temperatures of up to around 1700°C. This is crucial to achieve full clinker formation in a cement kiln. Reaching this temperature with non-combustion style kilns, such as solar reactors, has previously been a problem. Notably, Synhelion and Cemex said in February 2022 that they had managed to produce clinker using concentrated solar radiation. Retrofit possibilities and compact equipment size are also mentioned in the promotional material for the RDH. The former is an obvious attraction but size of equipment footprint is increasingly emerging as a potential issue for cement plants looking to reduce their CO₂ emissions. Rick Bohan from the Portland Cement Association (PCA) presented a summary of the potential and problems of emerging carbon capture and utilisation/storage (CCUS) technologies for cement plants in the US at the Virtual Global CemCCUS Seminar that took place on 14 June 2022. He noted that installing CCUS equipment makes cement plants start to look different (more like petrochemical plants in the view of Global Cement Weekly) and that they may require more space to install it all.

Coolbrook hasn’t been the only organisation looking at kiln electrification. The installation with the most available information on kiln electrification has been the Decarbonate project, led by the VTT, formerly known as the Technical Research Centre of Finland. The project has built a pilot rotary kiln with a length of 8m inside a shipping container. It has a production capacity of around 25kg/hr. The system reportedly uses fixed radiant heating coils around the kiln, surrounded by insulation materials. Early results presented to the 1st Virtual Global CemPower Seminar in late 2021 were that the kiln started up, sufficient calcination was occurring and the system was operated continuously for three days at a temperature of 1000°C with no problems reported. Further research was scheduled to carry on into 2022 with longer trials planned for three different materials.

HeidelbergCement’s subsidiary in Sweden, Cementa, completed a feasibility study on implementing electrified cement production at its Slite plant in 2019. It then said that it was conducting further study with electricity producer Vattenfall as part of CemZero project. This consists of three projects running to 2025. Namely: heat transfer with plasma in rotary kilns; direct separation of carbon dioxide from calcination of carbonate-based raw materials in the production of cement clinker and burnt lime; and carbon dioxide-free products with electrified production - reactivity of cement clinker with secondary additives. HeidelbergCement has since announced plans to build a full scale 1.8Mt/yr carbon capture and storage (CCS) plant at the Slite cement plant by 2030.

How this would fit with any kiln electrification plans is unknown. However, one attraction of moving to an electrical kiln, for all of the projects above, is to cut out the 40 – 50% of a cement plant’s CO₂ emissions that arise from the fuel that is burnt. Taking a kiln electric also makes CO₂ capture easier. Much of the remainder of the CO₂ released comes from the decomposition of limestone during calcination when clinker is created. Substitute out fossil or alternative fuels and the flue gas becomes much purer CO₂.

It is early days for cement kiln electrification but progress is happening both commercially and scientifically. The next step to watch out for will be the first pilot installation at a cement plant. One point to finish with is a comment that Rick Bohan made at the IEEE-IAS/PCA Cement Industry Technical Conference that took place in May 2022: carbon capture is expected to double a cement plant’s energy consumption. Kiln electrification is one potential route for cement production to reach net zero. CCUS is another. If one or both occur then a low carbon future could be a high energy one also.

Watch out for Global Cement’s forthcoming interview with Coolbrook in the September 2022 issue of Global Cement Magazine

For more on CCUS, download the proceedings pack for the Virtual Global CemCCUS Seminar 2022

For more on Synhelion and Cemex read the interview in the December 2020 issue of Global Cement Magazine interview