Displaying items by tag: blast furnace slag

UK: UK-based startup Cocoon has raised €4.9m in pre-seed funding to develop technology that repurposes byproducts from electrified steel furnaces into a ‘near-identical replacement’ for blast furnace slag, according to the company. The modular technology integrates into existing steel-making processes without disrupting operations or requiring high capital expenditure, reports UK Tech News. Cocoon targets a 50% replacement of cement in concrete, aiming to reduce emissions for producers. Initial tests are underway at a steel plant in northern England, followed by another in the US.

Cocoon CEO Eliot Brooks said "We’re turning a byproduct with little use into a valuable product that the market badly needs and can be easily integrated into existing supply chains. By repairing a broken link in the circular economy, Cocoon provides steel makers with a new revenue stream while meeting the low-carbon material needs of the concrete industry. For every 1t of Cocoon’s slag-based cementitious material used, 1t of CO₂ can be avoided."

Brooks hopes Cocoon's climate technology will be integrated into a pilot plant by late 2025.

India: The Samruddhi Expressway stretches 701km from Nagpur to Mumbai. This project by the Maharashtra State Road Development Corporation (MSRDC) has been focused on reducing environmental impact by the use of fly ash and blast furnace slag in its concrete.

Anil Gaikwad, managing director of the MSRDC, said "Fly ash and ground granulated blast furnace slag were also used in the concrete,” He continued “Fly ash has been used to the extent of 20% in the concrete."

The project emphasised circularity by reusing and recycling materials. Responsible sourcing of materials was a key component, ensuring vendors complied with environmental standards. Innovative water management strategies were also implemented, including the creation of farm ponds through agreements with local farmers.

US: The United States Geological Survey (USGS) estimates that the US sold 17Mt of ferrous slags in 2021, a rise of 31% year-on-year from the estimate in 2020. Blast furnace slag represented about 49% of the volume sold and accounted for 87% of the total value ofslag, most of which was granulated. Steel slag produced from oxygen and electric arc furnaces accounted forthe remainder of sales. Slag was processed by 28 companies servicing active iron and steel facilities or reprocessing old slag piles at about 124 processing plants, including some iron and steel plants with more than one slag-processing facility, in 33 States, including facilities that import and grind unground slag to sell as ground granulated blast furnace slag (GGBFS).

A further 2.2Mt was imported, a slight decline from 2020. From 2017 to 2020 the USGS reports that 42% of imported slag came from Japan, 18% from Brazil, 11% from China and 10% from Italy.

The USGS noted that during 2021, domestic 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. Grinding of granulated blast furnace slag was only performed domestically by cement companies. However, following Covid-19 related decrease in availability in 2020, supply of steel slag increased in 2021.

Australia: Researchers from the University of New South Wales (UNSW) and CRC for Low Carbon Living (CRCLCL) are testing a geopolymer concrete made from fly ash and blast furnace slag on a road in Sydney. A 30m stretch of road is being trialled with 15m of traditional concrete and 15m of a geopolymer concrete. Nine sensors have been positioned under the concrete to monitor and compare how the geopolymer concrete performs. The results from the trial will be used to create the first set of industry guidelines for geopolymer concrete.

“While we’ll monitor the road performance for up to five years, a lot of the data collected in the first three to 12 months of this world-first trial will be used to confirm our models and strengthen our predictions,” said Professor Stephen Foster, Head of the School of Civil and Environmental Engineering at UNSW and the CRCLCL project lead.

US: The United State Geological Survey (USGS) estimates that 16Mt of ferrous slag was produced in 2018. Blast furnace slag accounted for about 50% of the sales volume. Nearly 90% of this value was from sales of granulated slag. Steel slag accounted for almost all of the remainder. 2.2Mt of slag was imported. Slag was processed by about 25 companies servicing active iron and steel facilities or reprocessing old slag piles at about 140 processing plants in 30 states.

The USGS said that locally produced granulated blast furnace slag was in limited supply in 2018 due to granulation cooling only being available at two active US blast furnaces. Supply of basic oxygen furnace (BOF) steel slag was similarly affected due to plant closures. As per 2017, ground granulated blast furnace slag (GGBFS) sales volumes have failed to match increases set by the overall US cement industry since 2010 despite positive long term trends.

US: The United State Geological Survey (USGS) estimates that 15Mt of ferrous slag was produced in 2017. Blast furnace slag accounted for about 50% of the sales volume. About 85% of this value was from sales of granulated slag. Steel slag accounted for almost all of the remainder. 2.2Mt of slag was imported. Slag was processed by about 25 companies servicing active iron and steel facilities or reprocessing old slag piles at about 175 processing plants in 30 states.

The USGS reported that the supply of blast furnace slag continued to be ‘problematic’ in the US due to the closure of blast furnaces and depleted slag piles. Supply of basic oxygen furnace (BOF) steel slag was similarly affected due to plant closures. However, ground granulated blast furnace slag (GGBFS) sales volumes have failed to match increases set by the overall US cement industry since 2010 despite positive long term trends.

North America: A survey by the North American Insulation Manufacturers Association (NAIMA) has revealed that its members used over 0.3Mt of recycled blast furnace slag in the production of thermal and acoustical insulation in 2017. The survey included data from both US and Canadian production plants.

Producers also used over 0.9Mt of recycled glass to produce residential, commercial and industrial thermal and acoustical insulation. Since the industry’s recycling program began in 1992, NAIMA estimates that its members’ plants have diverted an estimated 26Mt of recycled materials from the waste stream.

“Our industry is tremendously proud of the substantial use of recycled content in the production of energy saving insulation products,” said Curt Rich, president and chief executive officer (CEO) of NAIMA. “These products ultimately reduce building energy use and decrease our carbon footprint. Over the long term, the fibre glass and mineral wool insulation industry expects to continue using substantial amounts of recycled content in the production of insulation products.”