Glossary

The main raw material used in the production of aluminium. Refined from bauxite, it is a compound of aluminium and oxygen, and its chemical formula is Al₂O₃. It takes two kg of alumina to produce one kg of aluminium.

Mixture of aluminium base metal with one or more alloying elements that are either metallic or non-metallic (such as silicon). Depending on the type and amount of elements, as well as the treatment, a difference is drawn between "casting alloys"and "wrought alloys". The aim of alloying is to enhance the properties of the base metal, e.g. its strength and corrosion resistance.

Products in a wide variety of shapes and cross-sections that are produced in the extrusion process.

This term aluminium metal plant is used to describe a plant that produces molten aluminium, casts it into shapes or ingots and then subjects some of these products to fabrication processes, such as extrusion and rolling, on the same site.

The main raw material used in the production of aluminium. Refined from bauxite, it is a compound of aluminum and oxygen, and its chemical formula is Al₂O₃. It takes two kg of alumina to produce one kg of aluminium.

Products in a wide variety of shapes and cross-sections that are produced in the extrusion process.

The term aluminium reduction plant refers specifically to the plant, or part of the aluminium metal plant, where the process of producing molten aluminium by electrolysis takes place.

Flat-rolled aluminium material, ranging in thickness from 0.06 to 5 mm, in long lengths for coiling. Aluminium strip is a semi-finished product that is produced in high volume from pure aluminium and aluminium alloys by high-speed rolling. Strip is subsequently processed into sheet and foil. Usually narrower and longer than aluminium sheet.

Positive electrode. Input material used in the electrolytic reduction process. Anodes consist of petroleum coke and coal-tar pitch. "Green" anodes are formed from these raw materials, then baked at temperatures of up to 1,250°C and subsequently used as electrically conductive anodes.

Carbon that is shaped and baked (calcined) at a high temperature into anodes used in prebake cells.

Carbon that is shaped and baked (calcined) at a high temperature into anodes used in prebake cells.

Sudden increase in cell voltage, due to either insufficient alumina being dissolved in the electrolyte or the temperature of the electrolyte being too low.

Mixture of petroleum coke and pitch which is added to the Søderberg anode and constitutes the positive pole in the cell. Anode paste is also used to produce prebaked anodes.

Ore with aluminum hydroxide as its main constituent; the initial material for the extraction of aluminium. Around four kilograms of bauxite are needed to produce one kilogram of aluminium. Bauxite takes its name from "Les Baux" in southern France where the red ore was first discovered in 1822. Today, over 90 per cent of bauxite comes from the tropical regions of Australia, West Africa and Brazil.

Extrusion ingot cut to length.

Negative electrode. The term is used to describe the cathodic part of a cell, i.e. the steel shell with lining. The actual cathode is the metal surface.

CO2 equivalents.

Drawn tubing usually produces product that meets more stringent specifications than extruded product of the same alloy and size. Cold drawing (a type of drawn tubing process) is where extruded stock is drawn through a die, or a series of dies, in order to reduce the outside dimension of the tube.

Splitting chemical compounds with the help of direct current. Used in the production of primary aluminium.

Electrolyte consists mainly liquid cryolite, aluminium fluoride and calcium fluoride. It is used to dissolve alumina.

Products in a wide variety of shapes and cross-sections that are produced in the extrusion process.

Products in a wide variety of shapes and cross-sections that are produced in the extrusion process.

The fabrication process involves further work and processing of extruded aluminium after it comes out of the extrusion press and is properly cooled and aged. Fabrication services can include joining (welding, bonding, riveting), forming (bending, stretching), and machining (cutting, drilling, mitering, notching).

Number of fatalities per 100 million hours worked.

Produced by rolling, aluminium foil is less then 0.02mm thick. It is impervious to gas and light, it is soft and flexible and is highly suitable for the packaging of food and medicines. Aluminium foil is used plain, e.g. for household foil, or converted, i.e. printed, coated, laminated or embossed.

Greenhouse gases

Waste that is harmful to health or to the environment, either directly or over an extended period of time, and thus requiring special treatment. National and supernational authorities often define which substances shall be treated as hazardous waste.

Aluminum with a degree of purity of minimum 99.98 per cent. High-purity aluminium is the starting material for products used in the electrical engineering, electronics and optical industries because of its high electrical and heat conductivity. It is produced by means of different processes, i.e. three-layer electrolysis or the zone refining process, depending on the degree of purity required.

Controlled heating of extrusion ingot.

The London Metal Exchange.

The LME price is the market price at which aluminium is currently being traded. Since the end of the 1970s, the LME price has been determined on the London Metal Exchange (LME) in US dollars. The LME price is the standard price for producers, fabricators, dealers and end-use industries.

Lost-time injuries per million hours worked.

This term metal plant is used to describe a plant that produces molten aluminium, casts it into shapes or ingots and then subjects some of these products to fabrication processes, such as extrusion and rolling, on the same site.

Medical treatment cases per million hours worked.

Net Operating Capital. Inventory turnover + net receivables. Measured in days or absolute monetary terms.

Nitrous gases, which act as acidifiers and may create local pollution.

Polyaromatic hydrocarbons.

Electrolytic reduction cell with prebaked anodes. These anodes have to be replaced regularly during the production process.

Most widely used casting process for the production of aluminium castings; a casting process in which molten aluminium or aluminium alloy is forced into a steel mould at pressures of between several hundredths to several thousands bar.

Aluminium which is produced from alumina using the electrolytic reduction process. Primary means that it is pure aluminium made directly from raw materials, for the first time. (Lat. primus = first).

Products in a wide variety of shapes and cross-sections that are produced in the extrusion process.

Qatar Aluminium, the joint venture project established to build and operate the primary aluminium plant in Qatar. Hydro and Qatar Petroleum each hold a 50 percent stake in the company. 

The term reduction plant refers specifically to the plant, or part of the metal plant, where the process of producing molten aluminium by electrolysis takes place.

The classical processes for producing sheet, strip and foil are hot rolling and cold rolling. During the rolling process, the rolling stock is pushed between two rotating steel cylinders with a gap slightly smaller than the thickness of the rolling stock. The cylinders draw in the strip by means of friction and press the metal through the gap to form the metal.

Indicates the number of restricted work cases per million hours worked.

Also known as recycled aluminium; aluminium derived from melting down production scrap (new scrap) or post-consumer aluminium products (old scrap). Up to 95 percent of the energy originally used to produce the primary aluminum is saved during recycling.

Products in a wide variety of shapes and cross-sections that are produced in the extrusion process.

A flat-rolled product of large length and diameter and narrow thickness.

Electrolytic reduction cell with a continuous anode. Anode paste has to be regularly added to the anode during the production process.

Sulfuric gases. They act as acidifiers.

Flat-rolled aluminium material, ranging in thickness from 0.06 to 5 mm, in long lengths for coiling. Aluminium strip is a high-volume, semi-finished product that is produced from pure aluminium and aluminium alloys by high-speed rolling.

Total Recordable Injuries = LTI + RWC + MTC.

TRI cases per 1,000,000 hours worked

Vereinigte Aluminium Werke, the Germany-based aluminium company acquired by Hydro in 2002.

The term is related to our efforts to contribute to a sustainable future and conveys our understanding of this concept.

Volatile organic compounds. These are organic chemical compounds that have sufficiently high vapor pressures under normal conditions to significantly vaporize and enter the atmosphere. They include a wide range of carbon-based molecules, such as aldehydes, ketones, and other light hydrocarbons.