ALUMINIUM PRODUCTION IN THE WORLD

& electricity use

BASIC INFORMATION FROM THE INTERNET

30. April 2015.

Zoran Otriblog (in Croatian): http://ekoloskaekonomija.wordpress.com/

http://www.alueurope.eu/about-aluminium/production-process/

Sastav zemljine kore:

With a share of 8 %, aluminium is the third most abundant element in the earths crust. Thus, the availability of raw material supplies for the production of aluminium is almost unlimited.

The common raw material for aluminium production, bauxite is composed primarily of one or more aluminium hydroxide compounds, plus silica, iron and titanium oxides as the main impurities. It is used to produce aluminium oxide through the Bayer chemical process and subsequently aluminium through the Hall-Heroult electrolytic process.

On a world-wide average 4 to 5 tonnes of bauxite are needed to produce two tonnes of alumina, from which one tonne of aluminium can be produced. In Europe, usually the average bauxite consumption is 4.2 tonnes per tonne of aluminium.

More than 160 million tonnes of bauxite are mined each year. The major locations of deposites are found in tropic and sub-tropic areas. Bauxite is currently being extracted in Australia, Central and South America (Jamaica, Brazil, Surinam, Venezuela, Guyana), Africa (Guinea), Asia (India, China), Russia (and Kazakhstan) and Europe (Greece).

The material is mainly extracted by open-cast mining, which has a variable and highly site-specific effect on the local environment. The primary ecological concerns connected to this operation are related to the clearing of vegetation, affect on local flora and fauna, and soil erosion. Also, the conservation of rain forests is a key concern often voiced with regard to bauxite mining. Only about 15% of the worlds bauxite mining is today conducted in tropical rain forests. The area affected by bauxite mining is about 160m/kt.

The original flora and fauna of much of the land involved in bauxite mining is restored once mining operations have ceased. For all forest areas used for bauxite mining, 80% is returned to native forests, the rest is replaced by agriculture, commercial forest, or recreational area, thereby making the area more productive for the local community. As far as rain forests in particular are concerned, however, the area used for bauxite mining in rain forests is almost totally reverted back to rain forest. 97% of operations have rehabilitation plans in place. (...)

Alumina production

Bauxite has to be processed into pure aluminium oxide (alumina) before it can be converted to aluminium by electrolysis. This is achieved through the use of the Bayer chemical process in alumina refineries. The aluminium oxide is released from the other substances in bauxite in a caustic soda solution, which is filtered to remove all insoluble particles. The residue of the Bayer process, called bauxite residue, is managed separately according to industry standards (read the Bauxite Residue Management guidelines, August 2014 update).

The aluminium hydroxide is then precipitated from the soda solution, washed and dried while the soda solution is recycled. After calcination, the end-product, aluminium oxide (Al2O3), is a fine grained white powder. Four tonnes of bauxite are required to produce two tonnes of alumina which in turn produces one tonne of aluminium at the primary smelter. In 2010, 87.4mil tonnes of alumina were produced world-wide.

Alumina refineries are often located near to bauxite mines for logistics reasons.

Electrolysis

Aluminium primary smelting and casting

Primary aluminium is produced in reduction plants (or smelters), where pure aluminium is extracted from alumina by the Hall-Hroult process. The reduction of alumina into liquid aluminium is operated at around 950 degrees Celsius in a cryolite bath under high intensity electrical current. This process takes place in electrolytic cells (or pots), where carbon cathodes form the bottom of the pot and act as the negative electrode. Anodes (positive electrodes) are held at the top of the pot and are consumed during the process when they react with the oxygen coming from the alumina. There are two types of anodes currently in use. All potlines built since the early 1970s use the prebake anode technology, where the anodes, manufactured from a mixture of petroleum coke and coal tar pitch (acting as a binder), are pre-baked in separate anode plants. In the Soederberg technology, the carbonaceous mixture is fed directly into the top part of the pot, where self-baking anodes are produced using the heat released by the electrolytic process.

At regular intervals, molten aluminium tapped from the pots is transported to the cast house where it is alloyed in holding furnaces by the addition of other metals (according to the users needs), cleaned of oxides and gases, and then cast into ingots. These can take the form of extrusion billets, for extruded products, or rolling ingots, for rolled products, depending on the way it is to be further processed. Aluminium mould castings are produced by foundries which use this technique to manufacture shaped components.

World-wide trends in production are shown in the following graph. Aluminium output has increased by a factor of 13 since 1950, making aluminium the most widely used non-ferrous metal. In 2010, the world-wide production of primary aluminium was about 42.6 million tonnes per year for and installed capacity of 53.6 million tonnes.

Very recently China developped its aluminium production very rapidly, and it is the biggest producer in the world with over 17 million tonnes of production.

The other main production areas are North America, Europe (4.2 Mt), former Cis, Africa, Australia, Brazil, India, and the Middle East. In Europe the main producing countries are Germany, France, Spain, Norway and Iceland. World-wide, production plants are mainly located where suitable electrical energy resources are available.

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en.wikipedia.org/wiki/List_of_countries_by_aluminium_production

This is a list of countries by aluminium production in 2012 (and 2013) based on USGS [ United States Geological Survey] figures.Rank Country/Region Aluminium production(thousands of tonnes) World 47,300[3]1 China People's Republic of China 21,500[3]2 Russia Russia 3,950[3]3 Canada Canada 2,900[3]4 United States United States 1,950[3]5 United Arab Emirates United Arab Emirates 1,800[3]6 Australia Australia 1,750[3]7 India India 1,700[3]8 Brazil Brazil 1,330[3]9 Norway Norway 1,200[3]10 Bahrain Bahrain 900[3]11 Iceland Iceland 825[3]12 South Africa South Africa 820[3]13 Qatar Qatar 600[3]14 Mozambique Mozambique 560[3]15 Argentina Argentina 460[3]16 Germany Germany 400[3]17 Oman Oman 36018 France France 34919 New Zealand New Zealand 32720 Iran Iran 32021 Tajikistan Tajikistan 27322 Egypt Egypt 26523 Indonesia Indonesia 25024= Kazakhstan Kazakhstan 24924= Romania Romania 24926 Spain Spain 23027 Venezuela Venezuela 200[3]28 Slovakia Slovakia 16129 Netherlands Netherlands 15030 Greece Greece 13531 Sweden Sweden 12932 Bosnia and Herzegovina Bosnia and Herzegovina 12633 Malaysia Malaysia 12034 Italy Italy 11035 Ghana Ghana 10036 Montenegro Montenegro 80

37= Turkey Turkey 6037= United Kingdom United Kingdom 6039 Azerbaijan Azerbaijan 5440 Cameroon Cameroon 5241 Japan Japan 5042 Slovenia Slovenia 4043 Nigeria Nigeria 2644 Saudi Arabia Saudi Arabia 5

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http://wordpress.mrreid.org/2011/07/15/electricity-consumption-in-the-production-of-aluminium/

Aluminium is a very useful metal; it is the most widely used non-ferrous* metal in the world. It has a very low electrical resistance and a very good strength-to-weight ratio and has therefore found many applications: from packaging in drinks cans and foil wrapping to aeroplane parts and power lines.

Luckily, aluminium is very common, making up about 8% by mass of the Earths crust (only silicon and oxygen are more abundant). Unfortunately aluminium is also very reactive so is never found in isolation like gold and silver are, but rather as a compound in one of 270 different minerals.

Aluminium is usually produced by extracted from bauxite, an ore made from a mixture of aluminium hydroxide, iron oxide, titanium dioxide and kaolinite. Because it is so reactive aluminium cannot be extracted economically using chemical processes; instead it is extracted by electrolysis in the Hall-Hroult process.

The Hall-Hroult process uses a huge amount of electricity; hundreds of thousands of amperes are used in each cell and a single plant may contain hundreds of cells connected in series. According to Alcoa, the worlds largest producer of aluminium, the best smelters use about 13 kilowatt hours (46.8 megajoules) of electrical energy to produce one kilogram of aluminium; the worldwide average is closer to 15 kWh/kg (54 MJ/kg).Worldwide production of aluminium in 2010 was 41.4 million tonnes. Using the figures above this means that 621 billion kilowatt hours of electrical energy were used in the production of aluminium. To put that in perspective, the total world production of electrical energy was 20261 billion kilowatt hours, meaning that more than 3% of the worlds entire electrical supply went to extraction of aluminium.

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http://mcgroup.co.uk/news/20120510/china-unable-satisfy-domestic-aluminium-consumption-high-output.html

China is Unable to Satisfy Domestic Aluminium Consumption despite High OutputMay 10, 2012

China owns the largest stake in the world aluminium production. The country generated 18 million tonnes in 2011, a rise by 1.8 million tonnes, or 11.1 percent, year on year.

The Chinese market for aluminium is not well-balanced as the demand surpasses availability there.

For instance, local buyers consumed 20.6 million tonnes in 2011. The figure was approximately 1.9 million tonnes, or 10.4 percent, higher than in 2010.

Chinese traders are forced to export certain volumes of the product annually in order to meet their clients demand.

Unwrought aluminium import volumes were slightly above 365,000 tonnes in 2010 in the country. However, the amount was well below the one a year earlier when it reached 1.74 million tonnes.

Aluminum waste and scrap imports amounted to 2.9 million tonnes in 2010, up by 300,000 tonnes, or 11.5 percent, year on year.

China-based aluminium companies also export the material. Their total unwrought aluminium exports were estimated at around 754,000 tonnes in 2010. The export volumes were almost two times lower in 2009.

Countrys aluminum waste and scrap exports were about 1.1 million tonnes in 2010, in comparison with 890,000 tonnes in the preceding year.