Talvivaara Mining Company
Encyclopedia
Talvivaara Mining Company plc is a Finnish
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

-based nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

 mining business operating in Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

. Listed on the London
London Stock Exchange
The London Stock Exchange is a stock exchange located in the City of London within the United Kingdom. , the Exchange had a market capitalisation of US$3.7495 trillion, making it the fourth-largest stock exchange in the world by this measurement...

 and Helsinki Stock Exchange
Helsinki Stock Exchange
The Helsinki Stock Exchange is a stock exchange located in Helsinki, Finland. Since 3 September 2003 it has been part of OMX, referred to as OMX Helsinki . Since NASDAQ's acquisition of OMX in February 2008, the official name of the Helsinki exchange has been NASDAQ OMX Helsinki.- History :The...

s, the company is a constituent of the FTSE 250 and OMXH25 indices.

History

The deposits, Kuusilampi and Kolmisoppi, were originally discovered in 1977, by the Geological Survey of Finland (GTK). Although the deposit was large, it was considered too poor for existing technology. Only bioheap leaching could concentrate the nickel enough, but the technology was still untested. The mining rights were eventually obtained by Outokumpu
Outokumpu
Outokumpu is a group of companies headquartered in Espoo, Finland, aimed at stainless steel. The company has approx. 8 000 employees in about 30 different countries worldwide...

 Corporation, which sold them at a nominal price of two euros to a former employee, Pekka Perä. The Talvivaara Mining Company was established in 2004 when it acquired the rights to mine sites at Sotkamo
Sotkamo
Sotkamo is a municipality of Finland, located in the Kainuu region. The municipality has a population of and covers an area of of which is water. The population density is .Vuokatti, west of Sotkamo, is a popular skiing resort...

 in Eastern Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

 from Outokumpu
Outokumpu
Outokumpu is a group of companies headquartered in Espoo, Finland, aimed at stainless steel. The company has approx. 8 000 employees in about 30 different countries worldwide...

. In 2006 a metals recovery trial was completed and the necessary financing was secured. Perä proceeded to list the company in London Stock Exchange
London Stock Exchange
The London Stock Exchange is a stock exchange located in the City of London within the United Kingdom. , the Exchange had a market capitalisation of US$3.7495 trillion, making it the fourth-largest stock exchange in the world by this measurement...

 in 2007 and later to Helsinki Stock Exchange
Helsinki Stock Exchange
The Helsinki Stock Exchange is a stock exchange located in Helsinki, Finland. Since 3 September 2003 it has been part of OMX, referred to as OMX Helsinki . Since NASDAQ's acquisition of OMX in February 2008, the official name of the Helsinki exchange has been NASDAQ OMX Helsinki.- History :The...

 in 2009.

The appropriate permits to commence mining were obtained in 2007 and metals production started late in 2008. The construction of the mine cost 560 million euros in 2007–2008, and an additional 22 million from HEX in 2009 enabled investments that increased production by 45%.

In 2010 the company announced the commencement of uranium production as a by-product from its normal mining operations in Sotkamo. The uranium produced will be in the form of yellowcake
Yellowcake
Yellowcake is a kind of uranium concentrate powder obtained from leach solutions, in an intermediate step in the processing of uranium ores. Yellowcake concentrates are prepared by various extraction and refining methods, depending on the types of ores...

 with an estimated annual production of approximately 350 tons. At a yellowcake price of $40/lb the uranium production could result in an additional €20m annual revenue. The capital investment costs were €30m and estimated annual production costs are €2m. The resulting uranium production is estimated to meet 80% of Finland's annual uranium demand, although reprocessing and enrichment would be required to be conducted abroad, and would effectively double the production of uranium in the EU. Currently, the uranium is deposited into the gypsum pond.

Sales

Norilsk Nickel, the world's leading producer of nickel, has made a 10-year contract with Talvivaara Mining Company to purchase the latter's entire output of the nickel and cobalt production at market prices.

Operations

The Talvivaara mine is one of the largest nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

 mines in Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

. The mine is located in Sotkamo
Sotkamo
Sotkamo is a municipality of Finland, located in the Kainuu region. The municipality has a population of and covers an area of of which is water. The population density is .Vuokatti, west of Sotkamo, is a popular skiing resort...

 in Eastern Finland and employs 400 people. It is an open-pit mine, 22 km from Sotkamo
Sotkamo
Sotkamo is a municipality of Finland, located in the Kainuu region. The municipality has a population of and covers an area of of which is water. The population density is .Vuokatti, west of Sotkamo, is a popular skiing resort...

 and 28 km from Kajaani
Kajaani
Kajaani is a town and municipality in Finland.It is the capital of the Kainuu region. It is located southeast of Oulujärvi , which drains to the Gulf of Bothnia along the Oulujoki . There are inhabitants and city surface area is of which is water. The population density is . The town is...

. The mine consists of two deposits 3 km apart, Kuusilampi and Kolmisoppi, and has an annual production capacity of over 10 million tonnes of ore
Ore
An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element....

. The mine has reserves amounting to 1 billion tonnes of ore grading 0.22% nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

, 0.13% copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

, 0.5% zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 and 0.02% cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

 thus resulting 2.2 million tonnes of nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

, 1.3 million tonnes of copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

, 5 million tonnes of zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 and 0.2 million tonnes of cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

. 90% of the nickel is deposited in black schist
Schist
The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is...

 rock, which contains 31% sulfides, most of which consist of iron sulfide minerals. Nickel-bearing sulfide minerals pentlandite
Pentlandite
Pentlandite is an iron-nickel sulfide, 9S8. Pentlandite usually has a Ni:Fe ratio of close to 1:1. It also contains minor cobalt.Pentlandite forms isometric crystals, but is normally found in massive granular aggregates. It is brittle with a hardness of 3.5 - 4 and specific gravity of 4.6 - 5.0 and...

, altered pentlandite and pyrrhotite
Pyrrhotite
Pyrrhotite is an unusual iron sulfide mineral with a variable iron content: FeS . The FeS endmember is known as troilite. Pyrrhotite is also called magnetic pyrite because the color is similar to pyrite and it is weakly magnetic...

 are present in low concentrations, but are accessible by bioheap leaching.

The metals are extracted by bioheap leaching
Bioleaching
Bioleaching is the extraction of specific metals from their ores through the use of living organisms. This is much cleaner than the traditional heap leaching using cyanide...

, a method where natural bacteria living in the rock accelerate metal leaching by oxidation. In conventional leaching, a coat of porous sulfide rock is left behind on the shrinking core of nickel in the grain. In contrast, in bioheap leaching, the oxidation of sulfides causes eventual disintegration of the porous rock, exposing more area than achievable by chemical means only. The ground ore is built into heaps 1.2 km long and 400 m wide, and a recycling irrigation system is used to keep the grains wet. The heat produced by the bacterial oxidation keeps the heap warm throughout the year. Extraction is done twice in primary and secondary heaps. In a pilot heap, over 90% of nickel and 80% of zinc was recovered within 500 days of leaching. Cobalt and copper recoveries were lower, 14% and 2%, respectively. The resulting green-colored solution is then refined to the metals. Treatment with hydrogen sulfide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

 precipitates copper sulfide
Copper sulfide
Copper sulfides describe a family of chemical compounds and minerals with the formula CuxSy. Both minerals and synthetic materials comprise these compounds. Some copper sulfides are economically important ores....

, then zinc sulfide
Zinc sulfide
Zinc sulfide is a inorganic compound with the formula ZnS. ZnS is the main form of zinc in nature, where it mainly occurs as the mineral sphalerite...

 and finally nickel-cobalt sulfide
Cobalt sulfide
Cobalt sulfide is the name for chemical compounds with a formula CoxSy. Well-characterized species include minerals with the formula CoS2 and Co3S4, and the synthetic material Co9S8...

.

In 2011 Cameco
Cameco
Cameco Corporation is the world's largest publicly traded uranium company, based in Saskatoon, Saskatchewan. In 2009, it was the world's second largest uranium producer, accounting for 16% of world production.-History:...

 signed an agreement with Talvivaara, where Cameco would pay US$ 60 million to construct a uranium extraction circuit at the mine in Sotkamo
Sotkamo
Sotkamo is a municipality of Finland, located in the Kainuu region. The municipality has a population of and covers an area of of which is water. The population density is .Vuokatti, west of Sotkamo, is a popular skiing resort...

. Talvivaara would then pay back the initial construction costs in the form of uranium concentrate; once the initial costs are paid Cameco would continue to purchase the uranium concentrate at a pricing formula based on market price on the day of delivery.

A railway track was built in order to transport the nickel-cobalt concentrate to a Norilsk Nickel smeltery in Harjavalta
Harjavalta
Harjavalta is a town and municipality of Finland.It is located in the province of Western Finland and is part of the Satakunta region. The town has a population of and covers an area of of which is water. The population density is ....

, Finland.

Environmental impacts

The operation has caused controversy because of its environmental impacts. Sulfate
Sulfate
In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...

 concentration in the effluent (8000 mg/m3) has exceeded the permitted levels (130 mg/m3), causing severe pollution in the water course.
The case is currently under police investigation.
Insufficient mixing caused the formation of an artificial halocline
Halocline
In oceanography, a halocline is a subtype of chemocline caused by a strong, vertical salinity gradient within a body of water. Because salinity affects the density of seawater, it can play a role in its vertical stratification...

 in a lake where effluent was discharged, which led to the lake bottom become anoxic. Reduction of sulfate into hydrogen sulfide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

by bacteria caused odour problems.
Also dust problems are reported.

External links

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