Displaying items by tag: ground granulated blast furnace slag

Romania: Liberty Galați said in June 2021 that it exported 50,000t of granulated blast furnace slag (GBFS) to France. The steel company said that a French cement producer will use the GBFS along with clay and gypsum in clinker-free cement production. The alternative cement reduces CO₂ emissions by 80% compared to ordinary Portland cement (OPC), according to the supplier. Liberty Galați’s operations generate 500,000t/yr of GBFS. It says that it has cement industry customers across Europe and Africa.

General Director Aida Nechifor said “Our ambition to become carbon neutral by 2030 involves a new metallurgical route – using direct iron reduction and smelting in electric arc furnaces – increased scrap metal recycling and a transition to domestically-generated green energy. However, we are very happy to be able to ensure that even the by-products of our current production process, such as GBFS, can be used better to help reduce the carbon footprint of other products.”

Germany: Holcim Deutschland, part of Switzerland-based LafargeHolcim, has launched its new ECOPlanet Zero carbon neutral cement. The producer says that it will offset the product’s CO₂ emissions through a peatland rewetting service provided by MoorFutures. The cement also has a low clinker factor due to the use of ground granulated blast furnace slag (GGBFS)-enriched binders.

Cement and binders sales director Matthias von der Brelje said “Holcim has been reducing the specific CO₂ emissions of binders very effectively for decades by using high-quality GGBFS.” He added, “In the future, we want to work with planners, contracting agencies and users to further advance the use of our CO₂-reduced binders. This helps our customers to realise their vision of sustainable building even better. In terms of product technology, the ECOPlanet series also has outstanding - and in some cases even better - properties than Portland cements, for example good workability, light colour, favourable heat development and high fatigue strength.”

UK: HeidelbergCement subsidiary Hanson has installed a solar and wind-powered hydrogen generation demonstration unit at its Port Talbot Regen ground granulated blast furnace slag (GGBFS) plant in Port Talbot in Neath Port Talbot. The company says that the project is part of a collaboration with Swansea University’s Energy Safety Research Institute under the European Research and Development Fund’s Reducing Industrial Carbon Emissions initiative. The hydrogen generated by the installation will replace natural gas in the GGBFS plant’s burners.

Head of sustainability Marian Garfield said, “It is estimated that cement is the source of just under 2% of UK CO₂ emissions. With demand for cement and cement replacement products predicted to increase by 25% by 2030, researchers and industry are working hard to reduce the level of CO₂ emissions associated with production. As a leading manufacturer, we take our responsibility very seriously. In the UK we have already achieved a 30% reduction in CO₂ emissions since 1990 across the business and have set an ambitious new target of a 50% reduction by 2030 from the same baseline. We are constantly looking to improve energy efficiency and carbon reduction at our cement and Regen GGBFS plants, so we are delighted to be involved with this innovative research project.”

UK: DB Group has supplied its Cemfree concrete product to a site in Birmingham, West Midlands for use by the Environment Agency in a flood defence project. It says that the agency will use the concrete “for kerb bedding and backing over several kilometres in conjunction with various recycled products in an effort to reduce the projects’ carbon footprint.” Cemfree is a low carbon concrete made using ground blast furnace slag (GGBS) and pulverised fly ash.

UK: CemFree cement-free concrete has been applied volumetrically for the first time in a 52m3 repair to the Woodford West Viaduct on the M25 London ordbital motorway in Essex. The reason behind the choice of method was the unavailability of batching plants at night, which was the only time that a team of Jackson, DB Group and Axtell employees working on behalf of Connect Plus were permitted to perform the work on the UK’s busiest road. CemFree said that 9.4t of CO2 emissions were cut by comparison to the same project undertaken with ordinary Portland cement (OPC). Jackson director of highways Paul Watson said, “We hope this marks a turning point on the M25 and the wider Highways sector for using low carbon alternatives.”

Cemfree uses 95% ground granulated blast furnace slag (GGBFS) and a 5% alkali activator, removing the need for cement. This gave CO2 emissions of 114kg/t, which the company says is 77% lower than conventional (OPC).

Charah Solutions has been steadily building up its fly ash distribution business in recent years with an eye on the supplementary cementitious materials (SCM) market. This week it opened the third of its new series of SCM grinding plants, at Oxnard in California, US. The unit sticks out because it is focusing on grinding natural pozzolans. The plant will receive natural pozzolan by truck and rail and then use Charah’s patented grinding technology to produce pozzolan marketed under its MultiPozz brand. The previous plants in this series mentioned natural pozzolans but this is the first to promote it explicitly.

The change is potentially telling because global demand for granulated blast furnace slag (GBFS) outstrips supply. Both performance benefits and environmental regulations are pushing this. It’s a similar situation for fly ash, also driven by trends to close coal-fired power stations in some countries. As Charles Zeynel of SCM trading firm ZAG International explained in the March 2019 issue of Global Cement Magazine, “...volcanic pozzolans are a potential SCM of the future. This is gaining traction, but it’s slow progress at the moment. This will be the answer for some users in some locations.”

The problem though is that natural pozzolans are down the list of preferred SCMs for their chemical properties after silica fume, GBFS and fly ash. The first is expensive but the latter two were traditionally cheap and easy to obtain if a cement or concrete producer had access to a source or a distribution network. Natural pozzolans are very much subject to variations in availability.

It’s no surprise then that Charah is promoting natural pozzolans in a Californian plant given that state’s environmental stance. It’s unclear where Charah is sourcing their pozzolan from but they are not the only company thinking about this in the US. Sunrise Resources, for example, is working on the environmental permits for a natural pozzolan mine near Tonopah in Nevada. As it described in its company presentation, California and Nevada are the most affected states in the fly ash supply crisis because they are, “...at the end of the line when it comes to rail deliveries from power stations in central and eastern USA.” It also estimated that California used 0.9Mt of pozzolan in its cement production of which about 90% is fly ash. The state produced 9.6Mt in 2015. Other companies are also mining and distributing natural pozzolans in the US as the website for the National Pozzolan Association (NPA) lists. Although, if this line-up is comprehensive, then the field is still fairly select. Most of these companies are based in the west of the country.

One last thing to consider is that various groups are tackling a potential future lack of SCMs for the cement industry by making their own pozzolanic materials through the use of calcined clay. These groups include the Swiss-government backed LC3 project and Cementir’s Futurecem products. Using clay should bypass the supply issues with natural pozzolans but the cost of calcining it requires at the very least an investment to get started.

As concrete enthusiasts often point out, a variant of pozzolanic concrete was used by the Romans to build many of their iconic structures, some of which survive to the present day. To give the last word to the NPA, “What is old is new again: natural pozzolan is back!” If environmental trends continue and steel and coal plants continue to be shut then it might just be right.

Once again Ecocem has shone the torch this week for a rare thing within Europe these days: a growing cement company. Its latest project is an import terminal in Sweden, as part of a deal with Bolidan, which launched on 22 September 2016. This supports an arrangement to supply cement for the Boliden Garpenberg mine. The agreement also includes supply for the Boliden Tara Mines in Ireland.

This follows the announcement to build a new slag grinding plant in Dunkirk, France in early September 2016 and the opening of a new terminal in Runcorn, UK earlier in the year. The 1.4Mt/yr Dunkirk plant is a joint-venture with the steelmaker ArcelorMittal, intended to target markets in north of France and in the UK. Once complete it will join Ecocem’s growing collection of grinding units in Ireland, France and the Netherlands. The slag-cement producer operates a 0.35Mt/yr plant at Dublin, a 0.7Mt/yr plant at Fos in the south of France and a 0.35Mt/yr plant at Moerdijk under its subsidiary Orcem Netherlands.

The focus on the UK makes sense given that Ecocem said that it had made commitments to sell more product in the UK in its first year than its total domestic sales in 2016. This followed the situation where, prior to entering the British market, Ecocem had to stop taking orders in the short term due to demand. If this is actually the case then it is unsurprising to note that Ecocem is also building a second UK terminal at Sheerness at the mouth of the River Thames near to London. As an aside, Francis Flower bought the Scunthorpe ground granulated blast furnace slag (GGBS) plant from Hanson Cement in mid-2015 after the local market regulator requested the sale.

As Charlie Zeynel, ZAG International, says in an interview to be published in the October 2016 issues of Global Cement Magazine, that supplementary cementitous materials, including slags, in cement blends has grown worldwide, particularly in Europe and Japan, where GGBS cement represents around 25% and 30% of cement sales respectively. Zeynel goes on to say that GGBS usage is set to rise in other parts of the world, particularly the US, but this helps to explain the market Ecocem is operating in within northern Europe.

Ecocem seems well aware of the potential for slag cements in the US because it is attempting to build a Euro45m grinding plant Vallejo, California under its Orcem Americas subsidiary. The process has so far been dogged by planning problems at the proposed site as well as organised local opposition, which does not want a new industrial plant in the neighbourhood and issues such as the increased traffic it would bring. The irony here is that Ecocem bills itself as an environmentally friendly cement producer. Yet even environmentally-friendly cement needs to be manufactured and taken to site.

To misquote Kermit the Frog: it’s not easy selling green cement. However, Ecocem’s progress in Europe is encouraging both in the UK and the wider area. Roll on the opening of the Sheerness terminal.

Find out more about Ecocem's operations here: www.ecocem.fr/en/

Tata Steel put up its UK business for sale last week. The Indian multinational declared that enough was enough having reported losses of over Euro2.5bn in the territory over five years. Non-UK readers may well wonder what the fuss is about. UK crude steel production comprised 10.9Mt in 2015 or about 0.7% of global production according to World Steel Association data according to World Steel Association data. By contrast the country produced 9.3Mt of cement in 2014 or about 0.2% of world production according to CEMBUREAU data according to CEMBUREAU data.

The UK’s flailing steel industry is worth discussing here for two reasons. Firstly, any decline in the local iron and steel industry will have implications for the supplementary cementitious materials (SCM) market as slag levels vary. Secondly, the cement industry in Europe may have lessons for a fellow heavy industry facing capacity rationalisation.

UK ground granulated blastfurnace slag (GGBS) production levels are low compared to total world supply. However, the UK Competition Commission certainly took note of the GGBS market in 2014. It was worried by LafargeTarmac’s and Hanson’s prominence in both the local GGBS supply chain and local cement production. At that time it ordered the HeidelbergCement subsidiary Hanson to sell one of its slag grinding plants to increase competition in the supply chain for GGBS. A GGBS plant in Scunthorpe was eventually sold to Francis Flowers in July 2015.

The general point here is that a Tata sale of its UK operations could have ramifications for the UK GGBS sector as existing deals are renegotiated following the shakeup. It would be even worse for the local slag market if any of the plants closed. No doubt the Competition Commission would also want to have its say to maintain some sort of competition in an already concentrated market. The UK cement market has been the bright spot in the multinational cement producers’ European regions in 2015. However, construction growth is starting to slow again with hints that the looming European Referendum in June 2016 may be having a negative effect. Uncertainty over GGBS supplies is not helpful in this atmosphere.

A wider lesson for other national cement industries looking in is that if Chinese steel continues flood the world market it will also hit the cement industry. Tata’s woes have been squarely blamed on China dumping its steel on the world market. Various jurisdictions promote the use of SCM cements and concrete for their low-carbon and sustainability properties. If local or existing GGBS supplies are hit then the cement industries may be penalised while the lawmakers and competition bodies play catch-up.

The wider point about heavy industry reducing its production capacity is one that the European cement industry will be well used to. Spain, for example, has seen its cement production drop from 55Mt in 2007 to 15Mt in 2014 according to Oficemen data. Alongside this, demand for cement has dropped to levels not seen since the 1960s. The European response has been to shut plants, sell assets and to merge companies.

The big question following the 2008 recession is whether ‘this’ is the new normal for mature construction markets. Eight years later global interest rates are still lagging and China’s economy is slowing down. All of the European infrastructure was built long ago meaning that steel and cement will only be required to maintain it. Luckily it looks likely that demand for SCMs should stay buoyant as industries are encouraged to decarbonise. The problem though is where the slag comes from. Oversupply in the short term in areas like Europe might be great for cement producers but as the iron and steel industries readjust to market reality there might be a hangover in store.