Ferrous metal cuttings in a form liable to self-heating

The processing of bauxite aluminium ore (hydrated alumina oxides) exemplifies these processes. In the Bayer process hot concentrated sodium hydroxide dissolves alumina which is subsequently separated and crystallized as aluminium hydroxide (hydrometallurgy). This is calcined to anhydrous alumina (pyrometallurgy) before being reduced in the Hall process (electrometallurgy) wherein alumina serves as the electrode from which elemental aluminium is deposited on the cathode. 

Metal scrap also includes enormous quantities of post-use items such as industrial machinery, vehicles, metal furniture, washing machines, and other consumer equipment, as well as metal residues from electroplating baths, wastewater treatment sludges, and the like. 

Magnesium alloys, see Metals, Alloys, p.l51 Metal, see Terminology, Metals, p.242 

Powder, see Terminology, Powder, p.246 and Metals, Elemental Products, p. 153 Self-heating, see Spontaneously Combustible Materials and Division 4.2, p.226 

Aluminium Processing By-Products. The material, consisting of skimmings of virgin aluminium, rising to the surface of impure molten aluminium metal. ICAO A2 

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