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.
