Displaying items by tag: ground granulated blast furnace slag

Heidelberg Materials North America held an official opening ceremony this week for its upgraded slag cement plant and terminal at Cape Canaveral in Florida. The US$24m project added a new roller press to the unit to increase its production capacity. In a statement Chris Ward, the president and chief executive officer of the company, said that it had made the investment to meet sustainability and resilient construction goals. Industrial Accessories Company (IAC) said in mid-2021 that it had been named as the engineering, procurement, and construction (EPC) contractor for the project. It planned to install a hydraulic roller press supplied by FLSmidth. IAC also said it was providing instrumentation equipment, hoppers, bins, belt conveyors, bucket elevators and dust collectors amongst other kit and services.

Other recent US slag cement-related news stories have concerned terminals. In late August 2022 Royal White Cement said it had leased a site on the Houston Ship Channel in Houston, Texas to handle and store approximately 100,000t of multiple cementitous products such as slag, ordinary Portland cement and white Cement. In May 2022 Titan America announced plans to spend US$37m on an upgrade to its Norfolk terminal in Chesapeake, Virginia. The major improvement was to add a 70,000t storage dome, with enlarged truck and railway capacity, to allow the site to import and distribute raw materials such as fly ash, slag and aggregates. Completion on this one was scheduled for some point in 2023. Titan added that the project was similar to the addition of a 70,000t dome under construction at the time at Titan's import terminal in Tampa, Florida.

The United States Geological Survey (USGS) estimates that domestic sales of iron and steel (ferrous) slags in the US amounted to 15Mt in 2022. Sales were around 20Mt in the 2000s but this fell to current levels in the 2010s as blast furnaces closed. In 2022 the USGS noted that, “domestic ground granulated blast furnace slag (GGBFS) remained in limited supply because granulation cooling was known to be available at only two active US blast furnaces while, elsewhere, only one domestic plant produced pelletised slag in limited supply.” It added that the grinding of granulated blast furnace slag was only being carried out domestically by cement companies. Imports of slag were 2Mt in 2022. This is a decline from a peak of 2.6Mt in 2018 but higher than the period 2000 – 2015. The price of slag, meanwhile, hit a high of US$53/t in 2022. This is the highest price recorded by the USGS since at least 2000. It is double that of 2017.

Charles Zeynel of ZAG International noted in the June 2023 issue of Global Cement Magazine that cement producers in Florida, California, Texas, Georgia and the Carolinas are far from steel mills, so they import granulated blast furnace slag (GBFS) and other secondary cementitious materials (SCM). This certainly fits with Heidelberg Materials’ plan to upgrade its slag cement plant and terminal at Cape Canaveral. Also on the US market, Zeynel added that due to rising global demand for SCMs more of the available share of GBFS was being purchased by ‘richer’ markets such as Europe, North America and Australia. He continued that GBFS and GGBFS producers had also started increasing the price of their wares internationally. This too is apparent in the prices published by the USGS.

One final story with links to slag to note this week concerns the launch of the Alliance for Low-Carbon Cement & Concrete (ALCC) in Europe. The group brings together companies producing products or services intended to decarbonise the cement and concrete sectors. Two of the members – Ecocem and Hoffman Green Cement Technologies – are Europe-based slag cement producers. Two other members – Fortera and TerraCO₂ – are companies based in North America that are marketing and selling low-carbon SCMs.

Various start-up companies have been emerging on a regular basis in both North America and Europe with the aim of decarbonising cement and concrete in various different ways. The formation of the ALCC can be seen as part of this trend as the more successful non-traditional cement-concrete-aggregate companies establish themselves. One point that cement producers in North America are likely to be well aware of is that concrete is becoming less linked to clinker as the cost of carbon mounts and the clinker factor of cement lowers. Slag supplies may be finite but Heidelberg Materials North America’s latest investment in Florida is further acceptance that one doesn’t just need clinker to make concrete.

Read Charles Zeynel’s interview on SCM Trends in 2023 in the June 2023 issue of Global Cement Magazine

The 15th Global Slag Conference, Exhibition & Awards take place on 6 - 7 June 2023 in Düsseldorf, Germany

France: Hoffmann Green Cement Technologies has commissioned its H2 plant, a 1000t/day clinker-free cement plant, adjacent to its existing H1 clinker-free cement plant in Bournezeau, Pays de la Loire. L'Usine Nouvelle News has reported that the new plant took 24 months to build and cost Euro22m. The main part of the plant consists of a 70m tower, where activated clay, ground granulated blast furnace slag (GGBFS) and gypsum are mixed to produce the cement. It is installed with solar panels capable of supplying 50% of its energy consumption. The producer says that its clinker-free cement has over 90% lower CO₂ emissions than cement produced with ordinary Portland cement (OPC). It aims to sell 24,000t of the product throughout 2023.

Finland: VTT Technical Research Centre subsidiary Carbonaide has concluded its seed funding round, having raised funds worth Euro1.8m. Lakan Betoni, which produces precast and ready-mix concrete, led the funding, along with utilities provider Vantaa Energy. Carbonaide will use the funds to build an industrial pilot plant for its carbon neutral precast concrete product at an existing precast concrete plant in Hollola. The plant will bind captured CO₂ in the product at atmospheric pressure. The process generates 50% lower CO₂ emissions than precast concrete production using ordinary Portland cement (OPC). Suitable raw materials include ground granulated blast furnace slag (GGBFS), green liquor dregs and bio-ash. In trial production, the use of GGBFS gave Carbonaide's concrete a negative carbon footprint of -60kg/m³.

Other sources of loans and in-kind contributions included Finnish state innovation fund Business Finland.

Peru: Unacem Perú plans to 'significantly increase' its cement production capacity 'in the medium-term future.' Prior to that, the producer will invest US$130m in capital expenditure during 2023, double what it invested in 2022. The investments will go towards slightly expanding the producer's capacity from 8.3Mt/yr and increasing alternative raw materials use in its cement production, including pozzolan and ground granulated blast furnace slag (GGBFS). Additionally, it will open its new Manchay limestone quarry in Pachacámac in early 2023.

Unacem said that it increased its cement sales 'unexpectedly' during 2022. It operated at 85 - 90% capacity utilisation, and continued to export clinker.

In Australia and New Zealand, four producers operate a total of six integrated cement plants, with another 13 grinding plants situated in Australia. This relatively small regional cement industry has been on a decades-long trajectory towards ever-greater sustainability – hastened by some notable developments in recent weeks.

Oceania is among the regions most exposed to the impacts of climate change. In Australia, which ranked 16th on the GermanWatch Global Climate Risk Index 2021, destructive changes are already playing out in diverse ways.¹ Boral reported 'significant disruption' to its operations in New South Wales and southeast Queensland due to wet weather earlier in 2022. This time, the operational impact was US$17.1m; in future, such events are expected to come more often and at a higher cost.

Both the Australian cement industry and the sole New Zealand cement producer, Golden Bay Cement, have strategies aimed at restricting climate change to below the 2° scenario. Golden Bay Cement, which reduced its total CO₂ emissions by 12% over the four-year period between its 2018 and 2022 financial years, aims to achieve a 30% reduction by 2030 from the same baseline. The Australian Cement Industry Federation (CIF)'s 2050 net zero cement and concrete production roadmap consists of the following pathways: alternative cements – 7%; green hydrogen and alternative fuels substitution – 6%; carbon capture – 33%; renewable energy, transport and construction innovations – 35% and alternative concretes – 13%, with the remaining 6% accounted for by the recarbonation of set concrete.

Australia produces 5.2Mt/yr of clinker, with specific CO₂ emissions of 791kg/t of clinker, 4% below the global average of 824kg/t.² Calcination generates 55% of cement’s CO₂ emissions in the country, and fuel combustion 26%. Of the remainder, electricity (comprising 21% renewables) accounted for 12%, and distribution 7%. Australian cement production has a clinker factor of 84%, which the industry aims to reduce to 70% by 2030 and 60% by 2050. In New Zealand, Golden Bay Cement's main cement, EverSure general-purpose cement, generates CO₂ at 732kg/t of product.³ It has a clinker factor of 91%, and also contains 4% gypsum and 5% added limestone.

Alternative raw materials

Currently, Australian cement grinding mills process 3.3Mt/yr of fly ash and ground granulated blast furnace slag (GGBFS). In Southern Australia, Hallett Group plans to commission its upcoming US$13.4m Port Augusta slag cement grinding plant in 2023. The plant will use local GGBFS from refineries in nearby Port Pirie and Whyalla, and fly ash from the site of the former Port Augusta power plant, as well as being 100% renewably powered. Upon commissioning, the facility will eliminate regional CO₂ emissions of 300,000t/yr, subsequently rising to 1Mt/yr following planned expansions. Elsewhere, an Australian importer holds an exclusive licencing agreement for UK-based Innovative Ash Solutions' novel air pollution control residue (APCR)-based supplementary cementitious material, an alternative to pulverised fly ash (PFA), while Australian Graphene producer First Graphene is involved in a UK project to develop reduced-CO₂ graphene-enhanced cement.

Golden Bay Cement is investigating the introduction of New Zealand's abundant volcanic ash in its cement production.

Fuels and more

Alternative fuel (AF) substitution in Australian cement production surpassed 18% in 2020, and is set to rise to 30% by 2030 and 50% by 2050, or 60% including 10% green hydrogen. In its recent report on Australian cement industry decarbonisation, the German Cement Works Association (VDZ) noted the difficulty that Australia's cement plants face in competing against landfill sites for waste streams. It described current policy as inadequate to incentivise AF use.

Cement producer Adbri is among eight members of an all-Australian consortium currently building a green hydrogen plant at AGL Energy’s Torrens Island gas-fired power plant in South Australia.

Across the Tasman Sea, Golden Bay Cement expects to attain a 60% AF substitution rate through on-going developments in its use of waste tyres and construction wood waste at its Portland cement plant in Northland. The producer will launch its new EcoSure reduced-CO₂ (699kg/t) general-purpose cement in November 2022. In developing EcoSure cement, it co-processed 80,000t of waste, including 3m waste tyres. The company says that this has helped in its efforts to manage its costs amid high coal prices.

Carbon capture

As the largest single contributor in Australia's cement decarbonisation pathway, carbon capture is now beginning to realise its potential. Boral and carbon capture specialist Calix are due to complete a feasibility study for a commercial-scale carbon capture pilot at the Berrima, New South Wales, cement plant in June 2023.

At Cement Australia's Gladstone, Queensland, cement plant, carbon capture is set to combine with green hydrocarbon production in a US$150m circular carbon methanol production facility supplied by Mitsubishi Gas Chemical Company. From its commissioning in mid-2028, the installation will use the Gladstone plant's captured CO₂ emissions and locally sourced green hydrogen to produce 100,000t/yr of methanol.

More Australian cement plant carbon capture installations may be in the offing. Heidelberg Materials, joint parent company of Cement Australia, obtained an indefinite global licence to Calix's LEILAC technology on 28 October 2022. The Germany-based group said that the method offers effective capture with minimal operational impact.

Cement Australia said “The Gladstone region is the ideal location for growing a diverse green hydrogen sector, with abundant renewable energy sources, existing infrastructure, including port facilities, and a highly skilled workforce." It added "The green hydrogen economy is a priority for the Queensland government under the Queensland Hydrogen Industry Strategy.”

Logistics

Australian and New Zealand cement facilities' remoteness makes logistics an important area of CO₂ emissions reduction. In Australia, cement production uses a 60:40 mix of Australian and imported clinker, while imported cement accounts for 5 – 10% of local cement sales of 11.7Mt/yr.

Fremantle Ports recently broke ground on construction of its US$35.1m Kwinana, Western Australia, clinker terminal. It will supply clinker to grinding plants in the state from its commissioning in 2024. Besides increasing the speed and safety of cement production, the state government said that the facility presents 'very significant environmental benefits.'

Conclusion

Antipodean cement production is undergoing a sustainability transformation, characterised by international collaboration and alliances across industries. The current structure of industrial and energy policy makes it an uphill journey, but for Australia and New Zealand's innovating cement industries, clear goals are in sight and ever nearer within reach.

References

1. Eckstein, Künzel and Schäfer, 'Global Climate Risk Index 2021,' 25 January 2021, https://www.germanwatch.org/en/19777

2. VDZ, 'Decarbonisation Pathways for the Australian Cement and Concrete Sector,' November 2021, https://cement.org.au/wp-content/uploads/2021/11/Full_Report_Decarbonisation_Pathways_web_single_page.pdf

3. Golden Bay Cement, 'Environmental Product Declaration,' 12 May 2019, https://www.goldenbay.co.nz/assets/Uploads/d310c4f72a/GoldenBayCement_EPD_2019_HighRes.pdf

US: Royal White Cement has leased a site on the Houston Ship Channel in Houston, Texas. Local press has reported that the company plans to build its second cement terminal in the city there. Houston Peninsula Terminals will operate unloading systems for the storage of cement across three facilities at the site. It is also equipped with multiple railway tracks and heavy truck loading facilities. Royal White Cement owner Marcel Fadi said that the move would help the producer to expand its footprint in Houston and beyond.

Fadi said "We have long operated in the Houston market, but this direct access to storage and bulk unloading along the channel will provide greater efficiencies and flexibility, allowing Royal White Cement to handle and store approximately 100,000t of multiple cementitious products such as slag, grey cement, and white cement."

Sri Lanka: Insee Cement has broken ground on its construction of a 45,000m³-capacity storage facility at Hambantota International Port. When commissioned in early 2023, the facility will store ground granulated blast furnace slag (GGBFS) for use in Insee Cement's cement production. Daily News has reported the cost of the facility's construction as US$3m. At 17,300m², the Hambantota storage facility will be the largest warehouse at any port in Sri Lanka.

Insee Cement chair and CEO Nandana Ekanayake said "Hambantota Port is a vital link in our raw materials supply chain. Insee Cement has been using this port since 2018 and so far we have cleared around 1.7Mt of bulk cargo through the port, of which we did a little over 1Mt in 2021. Today, we laid this foundation as another step to strengthen our partnership with Hambantota International Port Group." Ekanayake concluded "We see great potential in developing channels through Hambantota International Port and we will double our investment in the future."

Germany: Loesche has published its Sustainability Report of its performance in 2021. The supplier’s Scope 1 and 2 CO₂ emissions declined by 6.1% year-on-year to 229t from 244t in 2020 and by 19% over the two years from 2019, when they totalled 282t. It reduced the share of Scope 2 emissions in the figure to 40% from 41% in 2020 and 45% in 2019.

Loesche offers emissions-reducing products to the global cement industry under the label Greenkey Solutions. These include its A/Fuel and H/combust ranges for alternative fuels and green hydrogen upgrades, its C/Clay range for clay calcining and grinding, its Digital/Ready 4.0! range for predictive process optimisation and smart asset management, its E/Slag range for ground granulated blast furnace slag upgrades and its S/Crete range for waste concrete recycling, as well as audits for retrofits. Together, Loesche says that its products can reduce the global cement sector’s carbon footprint by 90%. Within this, Loesche believes that calcined clay technology alone can reduce cement’s CO₂ emissions by 40% and its energy demand by 21%.

Loesche said that its launch during the year of its H₂Optimum grinding bed spraying system can reduce grinding mills’ water consumption by 50%.

A trio of slag cement stories have been in the sector news this week with reports from Australia, France and Sri Lanka. Of note from the first two reports is a focus on supplies of slag.

The first concerns Hallett Group’s US$80m supplementary cementitious materials (SCM) project in South Australia. This will see the company process slag and fly ash sourced from sites in the region to manufacture blended cement products and standalone SCMs. These will be principally milled, blended and distributed from a site at Port Augusta. However, an additional distribution site at Port Adelaide is also planned that can both import and export the company’s products in a bid to cut down on supply chain risk, particular for its mining customers. The company says it will replace up to 1.15Mt/yr of cement when fully operational, although initial production looks set to be about a third of this based on local media reports. Commissioning of the Port Adelaide distribution hub is scheduled for May 2023, following by the Whyalla Granulator in January 2024 and the Port Augusta processing plant in June 2024. Pointedly, Hallett Group is explicit about where is plans to source its SCMs from: Nyrstar Port Pirie and, potentially, Liberty GFG.

The second slag-themed story hails from France, where Hoffmann Green Cement has acquired ABC Broyage, which operates a slag grinding plant in North Dordogne. Like the project in Australia above, Hoffmann Green is focused on its supply chain. With this acquisition it will be able to grind its own blast furnace slag instead of buying it. Raw blast furnace slag will be imported via the port of La Rochelle where the company has storage silos. It will then be ground at the former ABC Broyage site and sent on to Hoffmann Green’s H1 and H2 production sites, located at Bournezeau in the Vendée region. Finally it will use it to manufacture its H-UKR and H-IONA cement products. There is no mention of how much the acquisition is costing Hoffman Green. Instead the emphasis, according to company founders Julien Blanchard and David Hoffmann, is very much to, “strengthen our control over our supply and secure our margins in the current highly inflationary context.”

Finally, the week’s third slag-themed cement story is from Sri Lanka, where local media reports that Insee Cement has started producing Portland Composite Cement, using SCMs such as slag, at its Ruhunu grinding plant. This story follows the trend of cement producers around the world switching to greater usage of blended cements, often for sustainability reasons. Unfortunately, political events in Sri Lanka are overshadowing everything else locally, with the president having fled amid social unrest provoked by the ongoing and severe economic crisis. To this end Insee Cement has astutely also donated medical supplies this week to the intensive care unit at the Colombo National Hospital.

These slag stories are important for the cement sector can be demonstrated by a recent update to the Center for International Climate and Environmental Research - Oslo’s (CICERO) research on global CO₂ emissions from cement production. When it published its estimate for 2021 it found that overall emissions were 2.6Bnt in 2021 or just over 7% of the world’s total CO₂ output. What is worse though, is that its data suggests that cement-based emissions have steadily grown year-on-year from 1.2Bnt in 2002. Apart from a dip in 2015 they have kept on rising! This can mostly be attributed to the growth of the Chinese cement industry in the early 2000s suggesting that a tipping point may be reached in the current decade as lowering cement production CO₂ intensity finally kicks in.

Slag and other SCM-based blended cements fit in here as they are one of the ‘easiest’ ways to reduce the clinker factor of cement and concrete and thereby reduce the sector’s CO₂ levels. Hence they keep popping up on the various roadmaps and reports for the cement industry to reach net zero. The flipside of this however is that slag is becoming harder to source as the demand for granulated blast furnace slag increases and less new steel plants get built, especially in North America and Europe. Hence the focus on the supply of slag in the first two news stories above. Blended cements may be the future but getting there will be far from simple.

Australia: Hallett Group plans to establish a slag cement grinding plant in Port Augusta, South Australia. Magnet News has reported the cost of the project as US$83.9m, towards which the producer has received US$13.4m in government funding. The plant will produce cement using South Australian ground granulated blast furnace slag (GGBFS) from Nyrstar’s Port Pirie and Liberty Primary Steel’s Whyalla steel refineries and fly ash from the site of the former Port Augusta power plant. Its operations will be 100% renewably powered. An accompanying new distribution facility at Port Adelaide will ship the cement to markets. The project will create 50 new jobs.

When the Port Augusta grinding plant becomes operational in 2023, its products will reduce regional CO₂ emissions by 300,000t/yr, subsequently rising to 1Mt/yr, according to the company’s expansion plans.

Hallett Group chief executive officer Kane Salisbury said "We're talking about 1% of the entire country's 2030 [CO₂ reduction] commitment, delivered through this project." Salisbury added "We're looking at turning South Australia into a global leader in manufacturing green cement."