or rods, formed into large slabs for rolling, atomized into powder, sent to an extruder, or transported in its molten state to manufacturing facilities for further processing. Ingot production using reverberatory furnaces The scrap aluminium is separated into a range of categories such as irony aluminium (engine blocks etc.), clean aluminium (alloy wheels). Scraps are classified according to ISRI (Institute of Scrap Recycling Industries). Depending on the specification of the required ingot casting, it will depend on the type of scrap used in the start melt. Generally, the scrap is charged to a reverberatory furnace (other methods appear to be either less economical and/or dangerous) and melted down to form a "bath". The molten metal is tested using spectroscopy on a sample taken from the melt to determine what refinements are needed to produce the final casts. After the refinements have been added, the melt may be tested several times to be able to fine-tune the batch to the specific standard. Once the correct "recipe" of metal is available, the furnace is tapped and poured into ingot moulds, usually via a casting machine. The melt is then left to cool, stacked and sold on as cast silicon–aluminium ingot to various industries for re-use. Mainly, cast alloys like ADC12, LM2, AlSi132, LM24 etc. are produced. These secondary alloys ingots are used in die cast companies. Tilting rotary furnaces are used for recycling of aluminium scrap, which give higher recovery compared to reverberatory furnaces (Skelner Furnace). Recycling rates According to 2020 data from the International Aluminium Institute, the global recycling efficiency rate is 76%. Around 75% of the almost 1.5 billion tonnes of aluminium ever produced is still in productive use today. Brazil recycles 98.2% of its aluminium can production, equivalent to 14.7 billion beverage cans per year, ranking first in the world, more than Japan's 82.5% recovery rate. Brazil has topped the aluminium can recycling charts eight years in a row. Europe Secondary aluminium recycling White dross, a residue from primary aluminium production and secondary recycling operations, usually classified as waste, still contains useful quantities of aluminium which can be extracted industrially. The process produces aluminium billets, together with a highly complex waste material. This waste is difficult to manage. It reacts with water, releasing a mixture of gases (including, among others, hydrogen, acetylene, and ammonia) which spontaneously ignites on contact with air; contact with damp air results in the release