Outotec

A

Agglomeration: The formation of a lump by the coalescence of smaller globules, refers to briquetting, nodulizing, sintering, etc.
Alumina: Aluminum oxide processed from bauxite ore; used as raw material in aluminum production.
Anode: In copper, nickel, cobolt and zinc production a rectangular metal plate with positive charge cast in a shape suitable for refining by the electrolytic process.
Anode furnace: A copper (or more seldom nickel) refining furnace, in which blister copper (or impure nickel) is fire refined.
Anode slime: Metals or metal compounds left at, or falling from, the anode during electrolytic refining, normally containing gold, silver and platinum group metals.
Atmospheric reactor: A hydrometallurgical reactor working at normal atmospheric pressure.
Autoclave: A hydrometallurgical reactor working at elevated pressure and temperature.

B

Bacterial leaching, bioleaching: The extraction of metals from their ores or concentrates using microorganisms.
Ball mill: A steel cylinder containing steel balls used to grind ore. The mill is rotated causing the balls to cascade and grind the ore.
Base metals: Metals usually considered to be of lower value, such as copper, lead, zinc and nickel, when compared with the noble metals gold, silver and platinum.
Bauxite: The main ore of aluminum.
Beneficiation: The treatment of mined material, making it more concentrated or rich.
Blast furnace: A tall, refractory lined vertical shaft furnace for the production of pig iron or hot metal for direct conversion into steel.
Brownfield: Brownfield investments are carried out at the existing site consisting mainly of expansion, modernization and maintenance.

C

Calcination, calcining: Heating ores, concentrates, precipitates or residues to decompose carbonates, hydrates or other gas forming compounds.
Carbon plant: Plant for the production of baked anode blocks, for use in the aluminum smelting electrolysis process.
Cathode: In copper, nickel, cobalt and zinc production, a rectangular metal plate with a negative charge used in electrolytic refining.
Cathode copper: Electrolytically refined copper that has been deposited on the cathode of an electrolytic bath of acidified copper sulfate solution.
Caustic: Sodium hydroxide solution, used for the extraction of alumina from bauxite in the Bayer process.
Chromite: An isometric chromium containing oxide ore mineral; also in black sands, the major source of chromium.
Chromium: An element that increases the hardenability of steel and in association with high carbon gives resistance to wear and abrasion.
Circulating fluidized bed (CFB),: A bed of small solid particles suspended and kept in motion by an upward flow of a fluid (as a gas).
Clarifier: A settling tank or other vessel for separating suspended solid matter from a liquid to produce clean liquid.
Concentrate: A mineral product containing valuable metals from which most of the waste rock has been separated.
Concentrator: A plant for the recovery of valuable minerals from ore in the form of concentrate. Located typically at the mine site, adjacent to the mine.
Conversion process: A hydrometallurgical process in which a less noble metal element in a sulfidic ore or concentrate having no value (e.g. iron) is substituted by a more noble, valuable metal element (e.g. copper, nickel) dissolved in the solution; thus enriching the ore or concentrate. Outotec has developed unique processing technologies based on this process.
Converting: In pyrometallurgy a process of removing impurities from molten metal or metallic compounds by blowing air through the melt.
Crude steel: The first solid steel product upon solidification of liquid steel in a steel mill.

D

Direct leaching: A hydrometallurgical processing technology that directly dissolves metals from sulfidic concentrates in a special leaching process
Direct reduction: An iron making process in which iron oxide pellets and/or lump iron ore, are reduced (oxygen removed) in solid state by a reducing gas, producing
Direct smelting: A pyrometallurgical process involving coal based direct smelting and reduction of iron ore to produce reduced molten pig iron that may be immediately refined
Downstream: Processes that occur later on in a production sequence, for example, from ore to metal.
DRI (direct reduced iron): Solid metallic iron product obtained upon direct reduction of high grade iron ore in solid state itself without being converted into liquid form like that in blast furnace.

E

Effluent: Generally considered to be pollution, such as the discharge from industrial works.
Electrolysis: An electrochemical process in which electric current is passed through a solution containing dissolved metals (electrolyte), causing the metals to be deposited
Electrolytic refining,: A hydrometallurgical process to refine metals, typically copper, by electrochemically dissolving the impure metal (as cast) anode into to the acidic electrolyte
electrorefining: and coincidently precipitating it selectively onto the cathode as pure metal.
Electrowinning: A hydrometallurgical process in which a valuable metal, typically copper, nickel, cobalt or zinc, dissolved in the acidic electrolyte is selectively recovered as
EPC: Engineering, procurement and construction.
EPCM: Engineering, procurement, and construction management.
Extraction: In mining and metallurgical industry, a term describing commonly separating and upgrading steps or series of steps in the production chain of a desired metal

F

Feasibility study: An engineering study designed to define the technical, economic, and legal viability of a capitalization project — like a mining project —
Ferroalloy: Metal alloy products such as ferrochrome, ferronickel, ferromolybdenum that are commonly used as tradeable raw materials for alloying in steel making.
Ferrous metals: A classification of a certain group metals commonly having chemical and physical properties next to iron, in addition to iron itself,
Fire refining: A pyrometallurgical process used for the removal of impurities from impure molten metals produced by the smelting process by introducing air and possibly fluxes into the molten metal.
Flash converting: A process whereby copper concentrate is first smelted in a primary smelting furnace to produce high-grade copper matte.
Flash smelting: A smelting process in which dried metal sulfide concentrates are blown with oxygen or oxygen-rich air in a hot hearth-type furnace such that the particles react rapidly with the oxygen to generate a large amount of heat, partially (controlled) oxidizing the concentrates and producing a molten matte phase containing the metal values, which will be further processed, and a molten slag.
Flotation, froth flotation: A method of separating metal-containing minerals from gangue, by adding chemicals to a pulp mixture of water and mineral rendering metal-containing minerals hydrophobic. The hydrophobic particles will cling to introduced air bubbles which pass through the mixture thus separating them from other particles. This selectivity is reached through the addition of chemical reagents to the pulp.
Flow sheet: An illustration showing the sequence of operations, step by step, in the production chain.
Flue gas desulfurization: A technology that employs a sorbent, usually lime or limestone, to remove sulfur dioxide from the gases produced by burning fossil fuels.
Fluidized bed (fluid bed, FB): See circulating fluidized bed.
Froth control: A control system dedicated to enhancing the performance of the flotation process.

G

Galvanizing: A chemical process that is used to coat steel or iron with zinc to reduce corrosion.
Green anode plant: Plant sector in the primary aluminum smelter to produce “green” (=“raw” or unbaked) anode blocks from calcined petroleum coke, recycled carbon material, using liquid coal tar pitch as binder, such blocks being used – after baking – as consumable anode in the aluminum smelting electrolysis.
Greenfield: Greenfield investments are carried out at a site where no mining or metals processing activity is carried out by the time of the investment.
Grinding: Size reduction into fine solid particles in a mill.

H

Heap leaching: A hydrometallurgical process whereby valuable metals, usually copper or gold, are leached from a heap of crushed ore by continuously irrigated
Hot metal: Molten carbon saturated raw iron (pig iron) tapped from a blast furnace or from a direct smelting furnace to be sent to the following steel making process.
HydroCopper: A new hydrometallurgical process developed by Outotec for producing high-quality copper directly from sulfidic copper concentrate using chloride leaching.
Hydrometallurgy: The treatment of ores, concentrates, and other metal-bearing materials by aqueous based wet chemical and physical processes, usually involving leaching,

I

Ilmenite: Iron and titanium bearing oxide mineral; the major valuable mineral for titanium; also in mineral sands.
Indurating: A pyrometallurgical process whereby unfired pellets are hardened at high temperature in an indurating furnace to give them mechanical strength
Industrial minerals: Usually non-metallic minerals used in industry and manufacturing processes in their natural state, for example clays, silica sand,
IPR: Intellectual property rights.

L

Laterite: Red soil developed in humid, tropical, and subtropical regions of good drainage, contains concentrations of iron oxides and hydroxides and aluminum hydroxides
Leaching: Dissolution from ore or concentrates typically after suitable comminution to expose the valuable minerals, by aqueous and chemical attack targeting
Lime saturator: A device that makes clarified saturated lime solution for drinking water plants.
Lump ore: Beneficiated high-grade ore in a lumpy form (typically 8-30 mm in diameter) for further downstream processing; in contrast to the finegrained ore concentrate.

M

Magnetic separation: Separation of magnetic materials from non-magnetic materials, using a magnet. An important process in the beneficiation of iron ores
Matte: An intermediate product of a smelter, being a mixture of metals (e.g., iron and copper or/and nickel and cobalt) with some contained sulfur.
Metallurgical feedstock: Raw material supplied to a metallurgical processing plant.
Metallurgy: Science/art of extracting metals from their ores. Also used to refer to the science of metals processing.
Mineral: An inorganic compound occurring naturally in the earth’s crust, with a distinctive set of physical properties, and a definite chemical composition.
Mineral deposit: A mineral occurrence of sufficient size and grade that it might, under favorable circumstances, be considered to have economic potential.

O

Ore: A mineral deposit that can be mined economically.
Oxide: A compound of oxygen with another element. Also referring to a mineral compound characterized by the linkage of oxygen with one or more metallic elements,

P

Paste thickener: A thickener, which concentrates solids much higher than conventional and high rate thickeners, but with an underflow that can be pumped.
Pellet: Spherical agglomerates (typically 8-18 mm in diameter) made (pelletized) of fine-grained particles to allow the suitability
Pelletizing: A method in which fine-grained moist material is rolled in a drum or on an inclined disk, so that the particles cling together and roll up into small, spherical pellets.
Permanent cathode: Stainless steel plates (approximately 1m x 1m) used as reusable cathodes for copper electrorefining and electrowinning processes.
Physical separation: Covers a wide range of techniques, such as magnetic, electrical, thermal, gravity and dense medium separation, filtration and liberation,
Pig iron: The product of the blast furnace.
Pilot plant: A non-commercial scale plant in which processing steps are systematically investigated under conditions simulating a full production unit to obtain engineering
Pressure leaching: See leaching.
Pyrite: The most common iron sulfide mineral. An important gold bearing mineral and a source of sulfur for sulfuric acid production.
Pyrometallurgy: Metallurgical operations that involve processing at temperatures above ambient conditions, generally involving chemical reactions, for example

R

Recovery: The amount of ore, mineral or element finally obtained through various processes in relation to its original amount. Usually expressed in percentage.
Reduction: In chemistry and metallurgy strictly, the process step when an element captures electrons and reduces to a lower reduction stage; meaning for metal elements
Refining: The removal of impurities from a metal to be refined. Both pyrometallurgical and hydrometallurgical refining methods are used.
Roasting: In pyrometallurgy, a pre-treatment process at elevated temperature to oxidize the ore or concentrate to be more suitable for the following downstream processing.
Rod mill: A mill for fine grinding, somewhat similar to the ball mill, but employing long steel rods instead of balls as the grinding medium.
Rodding shop: Plant sector in the primary aluminum smelter to process used anode assemblies, separate the bath (flux) and carbon residue,
RTD: Research and technology development.

S

Selenium: A non-metallic element that closely resembles sulfur in its properties. A typical by-product recovered when processing copper concentrates;
Sinter: In pyrometallurgy, baked agglomerates of fine-grain particles that stick together in roughly one to two-inch lumpy chunks to allow more suitable
Sintering: A pyrometallurgical process used to agglomerate fine ore. This is necessary because in their original condition fine ores would choke
Slag: The vitreous mass of molten glass-like material separated floating from the molten metals in the smelting, converting or fire refining process.
Slime treatment: Anode slimes are the metals or metal compounds left at, or falling from, the anode during electrolytic refining of metals, typically copper.
Slurry sampling: Sampling of water or a liquid containing a high concentration of suspended solids. Often referring to sampling of different process phases
Smelting: A pyrometallurgical thermal processing operation in which the metal (or matte) is separated in molten form from non-metallic materials or other
Solution purification: An essential part of hydrometallurgical processing chain, after the first leaching step, where impurities are separated by different means from the leach solution
Solvent extraction (SX): A wet chemical/hydrometallurgical process to extract selectively desired species, typically desired dissolved metal, from an aqueous
Spent acid regeneration: A recovery process that re-produces sulfuric acid from contaminated, used (spent) sulfuric acid. Costs are much higher compared to
Stripping machine: A device for removing the refined metal, typically copper or zinc, from the (permanent) cathode.
Sulfide: A mineral compound characterized by the linkage of sulfur with a metal (or metals) or semimetal (semimetals), for example, pyrite.
Sulfur dioxide: Poisonous gas, which has a pungent, irritating odor and which is a typical by-product of a (copper, nickel, zinc) sulfide smelter used as raw material
Sulfuric acid: A dense, colorless liquid base chemical of the chemical industry. Used extensively for production of fertilizers and to leach stockpiles of oxidized copper ore.
Synthetic rutile: A synthetic tetragonal oxide mineral in which titanium replaces iron; an intermediate raw material of titanium.

T

Tank farm: A plant section between solvent extraction and electrowinning phases in hydrometallurgical copper production, used for circulating the solvents
Thickening: The concentration of the solids in a suspension with a view to recovering (most of) the solids in a fraction (underflow) with a higher concentration
Titanium: A metallic element found in nature only in compounds; occurs chiefly in ilmenite, rutile and titanite.
Traveling grate: A type of furnace in which assembled links of grates are joined together in a perpetual belt arrangement, typically used for iron ore sintering and pelletizing.

U

Upstream: Early activities of the production chain, for example, mine to metal value chain.

Glossary