Editing Slag (section)

{{Short description|By-product of smelting ores and used metals}}
{{about|the metalworking by-product|the British slang term for a promiscuous woman|Slut|the Scots word for a mixture of sleet, rain, and snow|Rain and snow mixed}}
[[File:Caletones.jpg|thumb|upright=1.15|Molten slag is carried outside and poured into a dump. Caletones copper smelter in [[El Teniente|El Teniente mine]], Chile.]]
The general term '''slag''' may be a [[by-product]] or co-product of [[smelting]] ([[Pyrometallurgy|pyrometallurgical]]) [[ore]]s and recycled metals depending on the type of material being produced.<ref name=":0">{{Cite journal|last1=Piatak|first1=Nadine M.|last2=Parsons|first2=Michael B.|last3=Seal|first3=Robert R.|date=2015|title=Characteristics and environmental aspects of slag: A review|url=http://dx.doi.org/10.1016/j.apgeochem.2014.04.009|journal=Applied Geochemistry|volume=57|pages=236–266|doi=10.1016/j.apgeochem.2014.04.009|bibcode=2015ApGC...57..236P |issn=0883-2927}}</ref> Slag is mainly a mixture of metal [[oxide]]s and [[silicon dioxide]]. Broadly, it can be classified as [[ferrous]] (co-products of processing iron and steel), [[ferroalloy]] (a by-product of ferroalloy production) or [[Non-ferrous metal|non-ferrous]]/[[base metal]]s (by-products of recovering non-ferrous materials like [[copper]], [[nickel]], [[zinc]] and [[phosphorus]]).<ref>{{Cite book|last1=Stroup-Gardiner|first1=Mary|last2=Wattenberg-Komas|first2=Tanya|date=2013-06-24|title=Recycled Materials and Byproducts in Highway Applications—Summary Report, Volume 1|url=http://dx.doi.org/10.17226/22552|doi=10.17226/22552|isbn=978-0-309-22368-3}}</ref> Within these general categories, slags can be further categorized by their precursor and processing conditions (e.g., [[blast furnace]] slags, air-cooled blast furnace slag, granulated blast furnace slag, [[basic oxygen furnace]] slag, and [[electric arc furnace]] slag). Slag generated from the EAF process can contain toxic metals, which can be hazardous to human and environmental health.<ref name="National Academies Press 2023 p. ">{{cite book | title=Health Risk Considerations for the Use of Unencapsulated Steel Slag | publisher=National Academies Press | publication-place=Washington, D.C. | date=17 Nov 2023 | isbn=978-0-309-70011-5 | doi=10.17226/26881 | page=| pmid=38190460 }}</ref>

[[File:IronAndSteelProduction.jpg|thumb|upright=1.15|Global production of iron and steel, 1942–2018, according to [[United States Geological Survey|USGS]].<ref>{{Cite web|title=Iron and Steel Statistics and Information|url=https://www.usgs.gov/centers/nmic/iron-and-steel-statistics-and-information?qt-science_support_page_related_con=0#qt-science_support_page_related_con|access-date=2021-11-27|website=www.usgs.gov}}</ref> ]]
Due to the large demand for ferrous, ferralloy, and non-ferrous materials, slag production has increased throughout the years despite recycling (most notably in the iron and [[steelmaking]] industries) and [[upcycling]] efforts. The [[World Steel Association]] (WSA) estimates that 600 kg of co-materials (co-products and by-products)(about 90 [[Mass fraction (chemistry)|wt%]] is slags) are generated per [[tonne]] of steel produced.<ref>{{Cite web|title=worldsteel {{!}} Steel industry co-products position paper|url=http://www.worldsteel.org/publications/position-papers/co-product-position-paper.html|access-date=2021-11-27|website=www.worldsteel.org|language=en}}</ref>