Zinc mining

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Zinkgruvan, a zinc mine in Askersund Municipality, Sweden Zinkgruvan zink mine Sweden 001.JPG
Zinkgruvan, a zinc mine in Askersund Municipality, Sweden

Zinc mining is the process by which mineral forms of the metal zinc are extracted from the earth through mining. A zinc mine is a mine that produces zinc minerals in ore as its primary product. Common co-products in zinc ores include minerals of lead and silver. Other mines may produce zinc minerals as a by-product of the production of ores containing more valuable minerals or metals, such as gold, silver or copper. [1] Mined ore is processed, usually on site, to produce one or more metal-rich concentrates, then transported to a zinc smelter for production of zinc metal. [2]

Contents

Global zinc mine production in 2020 was estimated to be 12 million tonnes. The largest producers were China (35%), Australia (12%), Peru (10%), India (6.0%), United States (5.6%) and Mexico (5.0%), with Australia having the largest reserves. [3]

The world's largest zinc mine is the Red Dog open-pit zinc-lead-silver mine in Alaska, with 4.2% of world production. [4] [5] Major zinc mine operators include Vedanta Resources, Glencore, BHP, Teck Resources, Sumitomo, Nexa Resources, Boliden AB, and China Minmetals. [5]

History

World zinc production, 1946 World- Zinc Production, 1946 - DPLA - 2f18a69219248aa357d5859b6d2cbe58.jpg
World zinc production, 1946

Zinc deposits have been exploited for thousands of years: the oldest known zinc mine, in Rajasthan, India, was established nearly 2000 years BP. [6]

Pure zinc was produced in the 9th century AD; earlier in antiquity zinc was primarily used to alloy with copper to produce brass. [7] This[ clarification needed ] is because it is difficult to isolate zinc metal from its ore. At the temperature zinc is released from its ore it also vaporizes into a gas, and if the furnace is not airtight, the gaseous zinc reacts with the air to form zinc oxide. [8] [9]

Metallic zinc was smelted in the 9th century BC in India, followed by China 300 years later, and in Europe by 1738 AD. [7] The methods of smelting in China and India were most likely independently developed, while the method of smelting developed in Europe was likely derived from the Indian method. [10] [7]

Modern uses

Primary modern uses for zinc
UseApprox %
worldwide
Coating iron and steel in order to prevent their corrosion (galvanization)50% [11]
Production of brass: the zinc is alloyed with copper in ratios of 20%–40% zinc. [11] 20%
Production of zinc alloys: the zinc is combined with varying proportions of aluminium and magnesium. [11] 15%
Various other industries, as an agricultural fertilizer and as a human food supplement. [11] 15%

Methods of extraction

Schematic cut and fill mining Method overview.png
Schematic cut and fill mining

Zinc is mined both at the surface and at depth. Surface mining of zinc is typically used for oxide ores, while underground mining yields zinc sulfide ores. [12] Some of the common methods of zinc mining are open pit mining, open stope, and cut and fill mining: [12] [8] [13] [14]

Open-pit mining : Surface mining involves the removal of waste rock from above an ore deposit before it can be extracted. Once the waste overburden is removed, ore and waste are then mined in parallel, primarily using track-mounted excavators and rubber-tired trucks. In smaller scale operations, front loaders may be used. [15]

Open Stope mining: This is a method of underground mining where ore bodies are completely removed leaving sizeable caverns (stopes) within the mine. Open stope mining leaves these caverns with no additional bracing or external support; instead the cavern walls are supported by random pillars of ore which have not been removed. [15]

Cut and Fill stoping: A method of underground mining which removes ore from below the deposit. The stope is then filled with waste rock to replace the mined out ore to support the stope walls, and to provide an elevated floor for the miners and equipment to further extract ore from the deposit. [15]

Production

Global mine production of zinc in 2019 was 12.9 million tonnes, a 0.9% increase from 2018, with the increase primarily attributed to increased output from zinc mines in Australia and South Africa. [16] [3]

In 2020, production of zinc is expected to rise 3.7% to 13.99 million tonnes, with the increase due to increased production of zinc by China and India. [17]

In 2019 global demand for refined zinc exceeded supply and resulted in a deficit of 0.178 million tonnes, while in 2020 there is an expected surplus of 0.192 million tonnes. [17]

Major zinc producing countries ranked by their output for 2023 [18]
CountryOutput (million tonnes)Share of world production
China433%
Peru1.412%
Australia1.19%
India0.867%
USA0.756%
Mexico0.696%
Bolivia0.494%
Other countries2.7123%

Environmental impact

Research on the health of the benthic macroinvertebrate populations in the mining areas of southeastern Missouri, USA, have yielded a wealth of information on the effects of zinc mining on its local environment. Fish and crayfish populations in localities near mining sites have been observed to be much lower than other populations found in reference sites; and the crayfish tissues have much higher metal concentrations than their reference counterparts. [19] It was also found that mussel populations near lead-zinc mining areas had reduced biomass, and were less specious[ clarification needed ] than those found in reference sites. [20] Concentrations of metals 10-60% higher than reference have been reported in plant tissues. [21] Immediately downstream of mining activity, a reduction in biotic condition of macroinvertebrates by 10%-58%[ clarification needed ][ Need to explain how biotic condition has been quantified. ] have been observed, with the ecosystem having an impaired ability to support its populations when compared to other reference sites. [22]

Benthic macro-invertebrates such as crayfish and mussels represent a pathway for biomagnification, where the concentration of noxious materials within organisms at higher trophic levels accumulates as a result of consuming contaminated prey. In addition, benthic macroinvertebrate populations are frequently used as indicators of overall ecosystem health. [19] [23] [24]

Soil samples from agricultural areas near a lead-zinc mining region in Guangxi, China have shown a "serious pollution level" of zinc in paddy fields relatively close to the mining area, and a "moderate pollution level" in the aerated fields relatively further away. [25] The research also indicated that their Nemerow synthetic index assessment[ clarification needed ] showed that the region under study is not fit for agricultural purposes. [25] Other investigation into the effect of zinc mining on agricultural soils in the Heilongjiang Province of China has found that the soils were "moderately contaminated", and the population and diversity of the bacterial assemblages within the soils were significantly reduced, with reduced activity of soil enzymes. [26] The activity of the bacteria and enzymes help plant matter to take up nutrients, decompose decaying matter, and in other ecosystem interactions. [26] Their reduction and impaired effectiveness result in poorer agricultural productivity.

Zinc mines

The world's ten largest zinc producing mines (by tonnes of zinc)
NameCountryOwner(s)Production
(tonnes)		Year and ref.Operations
Red Dog USA Teck Resources 552,400(2019) [4] Open-pit zinc-lead-silver mine
Rampura Agucha India Vedanta Resources (64.9%)
Government of India (29.5%)
[ Article says fully owned by Vedanta ]		357,571(2019) [27] Underground zinc-lead-silver mine
Mount Isa Australia Glencore 326,400(2019) [28] George Fisher and Lady Loretta underground lead-zinc-silver mines
Antamina Peru BHP (33.75%)
Glencore (33.75%)
Teck Resources (22.5%)
Mitsubishi Corporation (10%)		303,555(2019) [4] Open-pit copper-zinc-molybdenum mine
McArthur River AustraliaGlencore271,200(2019) [28] Open-pit zinc-lead-silver mine
San Cristóbal Bolivia Sumitomo Corporation 206,100(2019) [29] Open-pit silver-lead-zinc mine
Dugald RiverAustralia China Minmetals 170,057(2019) [30] Underground cut and fill stoping
VazanteBrazil Nexa Resources 139,000(2019) [31] Underground and open pit zinc-lead-silver mine
Cerro LindoPeruNexa Resources126,000(2019) [31] Underground zinc-lead-copper-silver mine
Tara Ireland Boliden AB 122,463(2019) [32] Underground zinc-lead mine

See also

Related Research Articles

<span class="mw-page-title-main">Ore</span> Rock with valuable metals, minerals and elements

Ore is natural rock or sediment that contains one or more valuable minerals concentrated above background levels, typically containing metals, that can be mined, treated and sold at a profit. The grade of ore refers to the concentration of the desired material it contains. The value of the metals or minerals a rock contains must be weighed against the cost of extraction to determine whether it is of sufficiently high grade to be worth mining and is therefore considered an ore. A complex ore is one containing more than one valuable mineral.

<span class="mw-page-title-main">Smelting</span> Use of heat and a reducing agent to extract metal from ore

Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron, copper, silver, tin, lead and zinc. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal behind. The reducing agent is commonly a fossil-fuel source of carbon, such as carbon monoxide from incomplete combustion of coke—or, in earlier times, of charcoal. The oxygen in the ore binds to carbon at high temperatures, as the chemical potential energy of the bonds in carbon dioxide is lower than that of the bonds in the ore.

<span class="mw-page-title-main">Underground hard-rock mining</span> Mining techniques used to excavate hard minerals and gems

Underground hard-rock mining refers to various underground mining techniques used to excavate "hard" minerals, usually those containing metals, such as ore containing gold, silver, iron, copper, zinc, nickel, tin, and lead. It also involves the same techniques used to excavate ores of gems, such as diamonds and rubies. Soft-rock mining refers to the excavation of softer minerals, such as salt, coal, and oil sands.

<span class="mw-page-title-main">Copper extraction</span> Process of extracting copper from the ground

Copper extraction refers to the methods used to obtain copper from its ores. The conversion of copper ores consists of a series of physical, chemical, and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.

Boliden AB is a Swedish multinational metals, mining, and smelting company headquartered in Stockholm. The company produces zinc, copper, lead, nickel, silver, and gold, with operations in Sweden, Finland, Norway, and Ireland.

<span class="mw-page-title-main">Southeast Missouri Lead District</span> Lead mining area in Missouri, US

The Southeast Missouri Lead District, commonly called the Lead Belt, is a lead mining district in the southeastern part of Missouri. Counties in the Lead Belt include Saint Francois, Crawford, Dent, Iron, Madison, Reynolds, and Washington. This mining district is the most important and critical lead producer in the United States.

<span class="mw-page-title-main">Kidd Mine</span> Kidd Township, Timmins area, Ontario

Kidd Mine or Kidd Creek Mine is an underground base metal (copper-zinc-silver) mine 24 km (15 mi) north of Timmins, Ontario, Canada. It is owned and operated by Swiss multinational Glencore Inc. The mine was discovered in 1963 by Texas Gulf Sulfur Company. In 1981, it was sold to Canada Development Corporation, then sold in 1986 to Falconbridge Ltd., which in 2006 was acquired by Xstrata, which in turn merged with Glencore in 2013. Ore from the Kidd Mine is processed into concentrate at the Kidd Metallurgical Site, located 27 km (17 mi) southeast of the mine, which until 2010 also smelted the ore and refined the metal produced. Following the closure of the majority of the Met Site, concentrate is now shipped to Quebec for processing. Kidd Mine is the world's deepest copper-zinc mine.

<span class="mw-page-title-main">Silver mining</span> Extraction silver from the ground

Silver mining is the extraction of silver by mining. Silver is a precious metal and holds high economic value. Because silver is often found in intimate combination with other metals, its extraction requires the use of complex technologies. In 2008, approximately 25,900 metric tons of silver were consumed worldwide, most of which came from mining. Silver mining has a variety of effects on the environment, humans, and animals.

<span class="mw-page-title-main">McArthur River zinc mine</span> Mine in Northern Territory, Australia

The McArthur River mine is a zinc-lead mine, situated about 70 kilometres southwest of Borroloola, near the Gulf of Carpentaria in the northeastern Northern Territory, Australia. It is operated by McArthur River Mining (MRM), a subsidiary of the Swiss mining company Glencore. Although discovered in the 1950s, when it was originally called the HYC or "Here's Your Chance" deposit, it only opened as a mine in 1995. Initially an underground mining operation, the mine has been converted to open-cut.

<span class="mw-page-title-main">Mining in Roman Britain</span>

Mining was one of the most prosperous activities in Roman Britain. Britain was rich in resources such as copper, gold, iron, lead, salt, silver, and tin, materials in high demand in the Roman Empire. Sufficient supply of metals was needed to fulfil the demand for coinage and luxury artefacts by the elite. The Romans started panning and puddling for gold. The abundance of mineral resources in the British Isles was probably one of the reasons for the Roman conquest of Britain. They were able to use advanced technology to find, develop and extract valuable minerals on a scale unequaled until the Middle Ages.

Mount Isa Mines Limited ("MIM") operates the Mount Isa copper, lead, zinc and silver mines near Mount Isa, Queensland, Australia as part of the Glencore group of companies. For a brief period in 1980, MIM was Australia's largest company. It has pioneered several significant mining industry innovations, including the Isa Process copper refining technology, the Isasmelt smelting technology, and the IsaMill fine grinding technology, and it also commercialized the Jameson Cell column flotation technology.

Lundin Mining Corporation is a Canadian company that owns and operates mines in Sweden, United States, Chile, Portugal and Brazil that produce base metals such as copper, zinc, and nickel. Headquartered in Toronto, the company was founded by Adolf Lundin and operated by Lukas Lundin. While it was incorporated to pursue an interest in a diamond mine in Brazil, the company re-structured and raised funds to develop the Storliden mine in Sweden. It purchased the Swedish Zinkgruvan Mine from Rio Tinto and then merged with Arcon International Resources for its Galmoy Mine in Ireland and with Eurozinc for its Neves-Corvo mine in Portugal. The company subsequently purchased and operated the Eagle mine, Candelaria mine, and Chapada mine.

<span class="mw-page-title-main">Mining in Tajikistan</span> Overview of mining industry in Tajikistan

Tajikistan has rich deposits of gold, silver, and antimony. The largest silver deposits are in Sughd Province, where Tajikistan's largest gold mining operation is also located. Russia's Norilsk nickel company has explored a large new silver deposit at Bolshoy Kanimansur. More than 400 mineral deposits of some 70 different minerals have been discovered in Tajikistan, including strontium, tungsten, molybdenum, bismuth, salt, lead, zinc, fluorspar, and mercury. These minerals have been found suitable for mining. Uranium, an important mineral in the Soviet era, remains in some quantity but is no longer being extracted. The Tajikistan Aluminium Company (TALCO), an aluminium smelter, is the country's only large-scale production enterprise in the mining sector. Tajikistan hosts the annual Mining World Tajikistan, an international exhibition on mining in Dushanbe.

<span class="mw-page-title-main">Tara Mine</span> Zinc and lead mine in Ireland

Tara Mines is a zinc and lead mine near Navan, County Meath, Ireland. Tara is an underground mine where the orebody lies between 50 and 900 metres below the surface. The orebody is within the carbonate-hosted lead-zinc ore deposits of the Navan Deposit.

<span class="mw-page-title-main">Environmental impact of mining</span> Environmental problems from uncontrolled mining

Environmental impact of mining can occur at local, regional, and global scales through direct and indirect mining practices. Mining can cause soil erosion, sinkholes, Biodiversity loss of biodiversity, or the [[Soil contamination, [[Groundwater pollution|, and surface water by chemicals emitted from mining processes. These processes also affect the atmosphere through carbon emissions which contributes to climate change.

<span class="mw-page-title-main">Nickel mining in New Caledonia</span>

Nickel mining in New Caledonia is a major sector of the New Caledonian economy. The island contains about 7.1 million tonnes of nickel reserves, about 10% of the world's total. With an annual production of 200,000 tonnes in 2020, New Caledonia was the world's fourth largest producer after Indonesia (760,000), Philippines (320,000), and Russia (280,000), followed by Australia (170,000) and Canada (150,000).

Rampura Agucha is a zinc and lead mine located on a massive sulfide deposit in the Bhilwara district of Rajasthan, India. Rampura Agucha is located 220 km (140 mi) from Jaipur. It is north of Bhilwara, and northwest of Shahpura. Rampura Agucha is 10 km (6.2 mi) southeast of Gulabpura on NH 79. The mine is owned by Hindustan Zinc Limited (HZL), and has the world's largest deposits of zinc and lead.

<span class="mw-page-title-main">Lead smelting</span> Process of refining lead metal

Plants for the production of lead are generally referred to as lead smelters. Primary lead production begins with sintering. Concentrated lead ore is fed into a sintering machine with iron, silica, limestone fluxes, coke, soda ash, pyrite, zinc, caustics or pollution control particulates. Smelting uses suitable reducing substances that will combine with those oxidizing elements to free the metal. Reduction is the final, high-temperature step in smelting. It is here that the oxide becomes the elemental metal. A reducing environment pulls the final oxygen atoms from the raw metal.

<span class="mw-page-title-main">Zinc mining in the United States</span>

Zinc mining in the United States produced 780,000 tonnes of zinc in 2019, making it the world's fourth-largest zinc producer, after China, Australia, and Peru. Most US zinc came from the Red Dog mine in Alaska. The industry employed about 2,500 in mining and milling, and 250 in smelting.

References

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