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58-528: Mining at El Teniente is reported to have started as early as 1819. In the early 20th century, two men from New York, United States set up a mining operation there, starting operations in 1906. Kennecott Copper Corporation , based in Utah , United States, later operated the mine through their subsidiary company. The Chilean government bought a 51% interest in the mine in 1967. Some 15,000 people lived in Sewell at its height as

116-541: A supergene mineral. The ore body surrounds the Braden Pipe in a continuous ring with a width of 2000 feet. The pipe is a geologic structure in the shape of an inverted cone, having a surface diameter of 4000 feet, and consisting of post-pipe breccia called the Braden Formation . The boundary of the pipe is marked by this post-pipe breccia and a pre-pipe breccia forming a belt up to 200 feet wide. "The Braden Pipe

174-499: A company town. In 1971 Chile nationalized copper production under President Salvador Allende and formed the state-owned copper mining company Codelco . This company still operates the mine. Workers began to live in other areas. With over 3,000 kilometres (1,900 mi) of underground drifts, El Teniente is reportedly "the world's biggest underground copper mine", and is the largest of Codelco's operations. Typically more than 5,000 workers were involved in production. Since 2011,

232-503: A copper and molybdenum concentrate from El Teniente's tailings . It has been granted the right also to treat higher grade tailings from a large, abandoned tailings impoundment near the El Teniente property. The copper ore deposits are those of a typical copper porphyry and associated alteration-mineralization . These altered zones include chalcopyrite , pyrite , bornite and molybdenite as hypogene minerals and chalcocite as

290-648: A cost of more than $ 450 million. KUC has spent more than $ 350 million on the cleanup of historic mining waste and $ 100 million on groundwater cleanup. Kennecott's copper mine concentrators, power plant and smelter is the leading facility for toxic releases in the state of Utah, according to a 2017 report by the US Environmental Protection Agency. The company's combined operations are believed to account for 3.5 percent of Salt Lake Valley's air pollution, according to Utah Department of Air Quality statistics. Editorialists continue to criticize Kennecott for

348-651: A division of Rio Tinto Group , is a mining , smelting , and refining company. Its corporate headquarters are located in South Jordan, Utah . Kennecott operates the Bingham Canyon Mine , one of the largest open-pit copper mines in the world in Bingham Canyon , Salt Lake County , Utah. The company was first formed in 1898 as the Boston Consolidated Mining Company . The current corporation

406-472: A report from a concerned citizen stating that berm dust from the mine's tailing evaporation ponds was blowing onto Interstate 80 , causing them malaise and sore throat each time they drove through it. The EEP recommended further studies to identify and quantify the levels of materials blown from the tailings ponds. Another Rio Tinto-owned company manages the non-mining land and water assets previously owned by KUC, Kennecott Land Company . Kennecott Land

464-427: A structural project called New Mine Level (NML) has been underway at El Teniente. It consists of expanding the mine deeper into the hill at 1,880 meters above sea level. The project is being carried out without interrupting the operation of El Teniente Division. According to legend, the El Teniente mine was discovered in the 1800s by a fugitive Spanish official. Exploitation of the resource began in 1819. The best ore

522-486: Is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS 2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale . Its streak is diagnostic as green-tinged black. On exposure to air, chalcopyrite tarnishes to a variety of oxides, hydroxides, and sulfates. Associated copper minerals include

580-404: Is a member of the tetragonal crystal system. Crystallographically the structure of chalcopyrite is closely related to that of zinc blende ZnS ( sphalerite ). The unit cell is twice as large, reflecting an alternation of Cu and Fe ions replacing Zn ions in adjacent cells. In contrast to the pyrite structure chalcopyrite has single S sulfide anions rather than disulfide pairs. Another difference

638-438: Is as follows: 2FeS (l) +3O 2(g) +SiO 2(s) -> Fe 2 SiO 4(l) + 2SO 2(g) + heat In the copper forming stage, the matte produced from the slag stage undergoes charging (inputting the matte in the converter), blowing (blasting more oxygen), and skimming (retrieving impure molten copper known as blister copper). The reaction is as follows: Cu 2 S (l) + O 2(g) -> 2Cu (l) + SO 2(g) + heat Finally,

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696-418: Is because of the extracting challenges which arise from the 1:1 presence of iron to copper, resulting in slow leaching kinetics. Elevated temperatures and pressures create an abundance of oxygen in solution, which facilitates faster reaction speeds in terms of breaking down chalcopyrite's crystal lattice. A hydrometallurgical process which elevates temperature with oxidizing conditions required for chalcopyrite

754-412: Is because the ore is primarily composed of non-economically valuable material, or waste rock, with low concentrations of copper. The abundance of waste material results in a lot of hydrocarbon fuel being required to heat and melt the ore. Alternatively, copper is isolated from the ore first using a technique called froth flotation . Essentially, reagents are used to make the copper water-repellent, thus

812-548: Is concentrated in this environment via fluid transport. Porphyry copper ore deposits are formed by concentration of copper within a granitic stock during the ascent and crystallisation of a magma. Chalcopyrite in this environment is produced by concentration within a magmatic system. Chalcopyrite is an accessory mineral in Kambalda type komatiitic nickel ore deposits , formed from an immiscible sulfide liquid in sulfide-saturated ultramafic lavas. In this environment chalcopyrite

870-525: Is considering alternatives that will keep the Bingham Canyon Mine open for additional decades. A massive rock slide at the mine in 2014 did not stop Rio’s plans to extend the mine’s life by another decade to 2029. The company says there’s still as much ore in the ground as miners have taken out of Bingham Canyon since it began production in 1906. The company proposes to expand the mine and reach an additional 700 million tons of ore resource by pushing back

928-598: Is formed by a sulfide liquid stripping copper from an immiscible silicate liquid. Chalcopyrite has been the most important ore of copper since the Bronze Age. Even though Chalcopyrite does not contain the most copper in its structure relative to other minerals, it is the most important copper ore since it can be found in many localities. Chalcopyrite ore occurs in a variety of ore types, from huge masses as at Timmins, Ontario , to irregular veins and disseminations associated with granitic to dioritic intrusives as in

986-478: Is known as pressure oxidation leaching . A typical reaction series of chalcopyrite under oxidizing, high temperature conditions is as follows: i) 2CuFeS 2 + 4Fe 2 (SO 4 ) 3 -> 2Cu + 2SO 4 + 10FeSO 4 +4S ii) 4FeSO 4 + O 2 + 2H 2 SO 4 -> 2Fe 2 (SO 4 ) 3 +2H 2 O iii) 2S + 3O 2 +2H 2 O -> 2H 2 SO 4 (overall) 4CuFeS 2 + 17O 2 + 4H 2 O -> 4Cu + 2Fe 2 O 3 + 4H 2 SO 4 Pressure oxidation leaching

1044-590: Is known locally as the Smoke Tragedy ( Spanish : La tragedía del humo ). In 1967 the Chilean government bought a 51% stake in the mine and founded Sociedad Minería El Teniente. Under this agreement Kennecott built a new concentrator, and the mine expanded production to 63,000 t (69,000 short tons) per day. On July 11, 1971, President Salvador Allende ordered the Chilean nationalization of copper , in an effort for

1102-480: Is limited substitution of zinc with copper despite chalcopyrite having the same crystal structure as sphalerite . Minor amounts of elements such as silver, gold, cadmium, cobalt, nickel, lead, tin, and zinc can be measured (at parts per million levels), likely substituting for copper and iron. Selenium, bismuth, tellurium, and arsenic may substitute for sulfur in minor amounts. Chalcopyrite can be oxidized to form malachite , azurite , and cuprite . Chalcopyrite

1160-416: Is much softer than pyrite and can be scratched with a knife, whereas pyrite cannot be scratched by a knife. However, chalcopyrite is harder than gold, which, if pure, can be scratched by copper . Chalcopyrite has a distinctive black streak with green flecks in it. Pyrite has a black streak and gold has a yellow streak. Natural chalcopyrite has no solid solution series with any other sulfide minerals. There

1218-473: Is particularly useful for low grade chalcopyrite. This is because it can "process concentrate product from flotation " rather than having to process whole ore. Additionally, it can be used as an alternative method to pyrometallurgy for variable ore. Other advantages hydrometallurgical processes have in regards to copper extraction over pyrometallurgical processes ( smelting ) include: Although hydrometallurgy has its advantages, it continues to face challenges in

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1276-410: Is practiced. The most important method for copper extraction from chalcopyrite is pyrometallurgy. Pyrometallurgy is commonly used for large scale, copper rich operations with high-grade ores. This is because Cu-Fe-S ores, such as chalcopyrite, are difficult to dissolve in aqueous solutions. The extraction process using this method undergoes four stages: Chalcopyrite ore is not directly smelted. This

1334-444: Is predominantly extracted from chalcopyrite ore using two methods: pyrometallurgy and hydrometallurgy . The most common and commercially viable method, pyrometallurgy, involves "crushing, grinding, flotation, smelting, refining, and electro-refining" techniques. Crushing, leaching, solvent extraction, and electrowinning are techniques used in hydrometallurgy. Specifically in the case of chalcopyrite, pressure oxidation leaching

1392-577: Is that the iron cation is not diamagnetic low spin Fe(II) as in pyrite. In the crystal structure, each metal ion is tetrahedrally coordinated to 4 sulfur anions. Each sulfur anion is bonded to two copper atoms and two iron atoms. Chalcopyrite is present with many ore-bearing environments via a variety of ore forming processes. Chalcopyrite is present in volcanogenic massive sulfide ore deposits and sedimentary exhalative deposits , formed by deposition of copper during hydrothermal circulation . Chalcopyrite

1450-437: Is typically done in flash furnaces. To reduce the amount of copper in the slag material, the slag is kept molten with an addition of SiO 2 flux to promote immiscibility between concentration and slag. In terms of byproducts, matte smelting copper can produce SO 2 gas which is harmful to the environment, thus it is captured in the form of sulfuric acid . Example reactions are as follows: Converting involves oxidizing

1508-542: The Albert Guay Affair , innocent bystanders killed in a private revenge. Guay had shipped a timed-explosive device in the luggage of his wife on this flight. When it exploded, she and all the other passengers and crew on the plane were killed. Charles Cox, formerly head of Carnegie-Illinois Steel , was hired shortly after to fill the executive vacuum at Kennecott. Guay and his two accomplices, Marguerite Pitre and Généreux Ruest, were all convicted of murder and executed for

1566-624: The American Smelting and Refining Company (ASARCO) to refine the Bingham Canyon ore. In 1907, the Utah Copper mill in Magna started operation. Utah Copper and Boston Consolidated merged in 1910. Five years later, in 1915, Kennecott acquired a 25% interest in the company. In 1915, to dilute the cost of railroad construction to support the mines, and to find new ventures for the capital produced by

1624-809: The porphyry copper deposits of Broken Hill , the American Cordillera and the Andes . The largest deposit of nearly pure chalcopyrite ever discovered in Canada was at the southern end of the Temagami Greenstone Belt where Copperfields Mine extracted the high-grade copper. Chalcopyrite is present in the supergiant Olympic Dam Cu-Au-U deposit in South Australia . Chalcopyrite may also be found in coal seams associated with pyrite nodules, and as disseminations in carbonate sedimentary rocks. Copper metal

1682-726: The Alaskan mine, Kennecott Copper Corporation was incorporated from the various financial interests involved. By this time, the Guggenheim Exploration was already actively working copper mines in Chile and Utah. Upon Kennecott's creation, they merged their Braden Copper Company property in Chile, as well as 25 percent of the Utah Copper Company, into Kennecott. These actions resulted in Kennecott taking possession of Braden's El Teniente ,

1740-506: The Cu is able to concentrate in a flotation cell by floating on air bubbles. In contrast to the 0.5–2% copper in chalcopyrite ore, froth flotation results in a concentrate containing about 30% copper. The concentrate then undergoes a process called matte smelting . Matte smelting oxidizes the sulfur and iron by melting the flotation concentrate in a 1250   °C furnace to create a new concentrate (matte) with about 45–75% copper. This process

1798-528: The El Teniente mine, where about 5,000 workers produce the ore. In 1983 El Teniente and two other Codelco mines closed when approximately 13,000 workers voted to strike "indefinitely" in protest of a union leader's arrest for calling for an end to military rule in Chile. In total among the three mines, at least 3,300 workers and 37 labour leaders were fired for participating in the strike. Contract workers went on strike at Codelco mines in 2008. El Teniente and two other Codelco mines were closed, El Teniente for

El Teniente - Misplaced Pages Continue

1856-607: The Jordan Valley Water Conservancy District to address two groundwater plumes located in southwest Salt Lake County. The plumes were caused by historical mining practices in the Kennecott South Zone. Approximately 80 square miles (210 km ) are impacted in the southwest portion of Salt Lake County. Because of the remediation efforts, which include more than a $ 100 million investment in a reverse osmosis facility, Kennecott's South End, (location of

1914-539: The amount of lead the smelter puts into the air each year: 6,250 pounds (2,830 kg). Environmental groups have lauded Rio Tinto’s decision to drop its requested permit for a new rock crushing plant at the copper mine. Kennecott originally wanted the crusher to shore up a mine-waste pond. Kennecott now says it can keep mining without expanding its tailings impoundment. In January 2012, the Utah Department of Health 's Environmental Epidemiology Program (EEP) received

1972-621: The beginning of long careers as copper workers. Issues of the company magazine 'Kennescope' in the 1950s emphasized the diversity of the work force. In 1953, there were 20 ethnic backgrounds, from Native American to Japanese. Kennecott laid off 200 workers in March 2016 due to a fall in global commodity prices. 40°32′50″N 112°00′13″W  /  40.5473°N 112.0035°W  / 40.5473; -112.0035 Chalcopyrite Chalcopyrite ( / ˌ k æ l k ə ˈ p aɪ ˌ r aɪ t , - k oʊ -/ KAL -kə- PY -ryte, -⁠koh- )

2030-484: The blister copper undergoes refinement through fire, electrorefining or both. In this stage, copper is refined to a high-purity cathode . Chalcopyrite is an exception to most copper bearing minerals. In contrast to the majority of copper minerals which can be leached at atmospheric conditions, such as through heap leaching , chalcopyrite is a refractory mineral that requires elevated temperatures as well as oxidizing conditions to release its copper into solution. This

2088-598: The bombing. By 1961, Kennecott's copper mines in the United States included four large open pits in Arizona , New Mexico , and Nevada . As the mine in Utah expanded, it subsumed the land on which the City of Bingham Canyon was built, and the city was disincorporated in 1971. In 1981, after a worldwide fall in copper prices, Standard Oil of Ohio (SOHIO) acquired Kennecott. Production

2146-580: The contaminated aquifer) was removed from the United States Environmental Protection Agency (EPA) National Priorities List (NPL). This investment represents one of many remediation projects along the Oquirrh Mountains to clean up historic mining sites. To date, Kennecott Utah Copper has remediated more than 10,000 acres (4,000 ha; 40 km ) of the total 40,000 acres (16,000 ha; 160 km ) impacted by mining at

2204-466: The copper strike of 1912, Utah Copper Company brought many Mexican and Mexican American strikebreakers to the Bingham mine. Most of them did not remain after the settlement of the strike. Company records reveal that, by 1918-19, large numbers of Spanish-surnamed individuals began to be employed at the mine, and additional Latinos were recruited during the labor shortages of WWII. For many of these men, it marked

2262-531: The copper used by the Allies. During the war, many women worked for the first time in the mines, mills, and smelters, replacing the men who had gone to war. On September 9, 1949 three Kennecott company officers were killed in an airplane bombing in Quebec . They were the retiring president E.T. Stannard; his designated successor, Arthur D. Storke; and R.J. Parker, a vice-president. They were incidental to what became known as

2320-494: The country to gain more benefit from the mines. Corporación Nacional del Cobre de Chile (known as Codelco ) was formed, and El Teniente became a state-owned operation. The Chilean government paid Kennecott $ 92.9-million for the property. The mine increased production to 100,000 t (110,000 short tons) of ore per day, and in 2006 the mine produced over 418,000 t (461,000 short tons) of copper. The Vancouver, British Columbia -based, Canadian company Amerigo produces both

2378-542: The former being the most commercially viable. The name chalcopyrite comes from the Greek words chalkos , which means copper, and pyrites ', which means striking fire. It was sometimes historically referred to as "yellow copper". Chalcopyrite is often confused with pyrite and gold since all three of these minerals have a yellowish color and a metallic luster. Some important mineral characteristics that help distinguish these minerals are hardness and streak. Chalcopyrite

El Teniente - Misplaced Pages Continue

2436-446: The matte once more to further remove sulfur and iron; however, the product is 99% molten copper. Converting occurs in two stages: the slag forming stage and the copper forming stage. In the slag forming stage, iron and sulfur are reduced to concentrations of less than 1% and 0.02%, respectively. The concentrate from matte smelting is poured into a converter that is then rotated, supplying the slag with oxygen through tuyeres . The reaction

2494-399: The mine and provided financing. In 1916 Braden became a subsidiary company of Kennecott Copper Corporation , which was based in Utah . Chileans have referred to such large-scale copper mining operations as La Gran Minería del Cobre (a major copper mine). Before nationalization, these operations generated a large proportion of the foreign currency which the country received. In 1945 there

2552-526: The modernization of KUC’s operations. In 2020, Kennecott Utah Copper directly employed 2,171 people and contributed to more than 14,000 indirect Utah jobs. Rio Tinto Group, one of the world's largest mining operations, comprises dual-listed companies Rio Tinto Limited (based in Melbourne) and Rio Tinto PLC (based in London). Although each company trades separately, the two Rio Tintos operate as one business. KUC

2610-407: The pre-pipe breccia." Mineralization at El Teniente is thought to be indebted to its position at the intersection of two large fault systems . This favoured the rise of magma and the subsequent circulation of mineral-rich fluids. As of 2007 Codelco employed 17,000 direct-hire company employees and 28,000 contract employees across all their operations. There have been multiple labour disruptions at

2668-486: The property and liked the prospects. Both men examined Wall's properties and recommended open-pit mining . In 1898, Samuel Newhouse and Thomas Weir formed the Boston Consolidated Mining Company. Jackling and Wall formed the Utah Copper Company on 4 June 1903, with Charles L. Tutt Sr. , Charles MacNeill, Spencer Penrose , Boies Penrose , Tal Penrose, and Dr. R.A.F. Penrose as investors. MacNeill

2726-752: The second-largest copper producer in the US, Kennecott Utah Copper provides about 8% of the US annual copper consumption of 1,700,000 tonnes. Kennecott’s Bingham Canyon Mine is the largest man-made excavation in the world. It is one of the top producing copper mines in the world with cumulative production over 17,000,000 tonnes (19,000,000 short tons) of copper. In 2020, Bingham Canyon produced 140,000 tonnes (310,000,000 lb) of copper, along with 171,200 troy ounces (5,320 kg) of gold, 2,205,000 troy ounces (68,600 kg) of silver, and 20,400 tonnes (45,000,000 lb) of molybdenum. Since Rio Tinto purchased Kennecott Utah Copper in 1989, it has invested about $ 2 billion in

2784-402: The shortest length. Company employees continued to work; however, striking workers closed access to the mines and threw stones at buses transporting employees from the mine to the town of Rancagua . At least one employee was injured; he was hit by a metal object thrown by a protester on the highway leading to the mine. Kennecott Copper Corporation Kennecott Utah Copper LLC ( KUC ),

2842-461: The south wall of the Bingham Canyon Mine 1,000 feet and deepening it 300 feet. Significant groundwater contamination exists in the aquifer downgradient of the Bingham Canyon mining operations. Starting in the late 1980s, the State of Utah Natural Resource Damage Trustee has overseen the investigation of mining-influenced groundwater and the implementation of cleanup actions performed by Kennecott and

2900-451: The sulfides bornite (Cu 5 FeS 4 ), chalcocite (Cu 2 S), covellite (CuS), digenite (Cu 9 S 5 ); carbonates such as malachite and azurite , and rarely oxides such as cuprite (Cu 2 O). It is rarely found in association with native copper . Chalcopyrite is a conductor of electricity. Copper can be extracted from chalcopyrite ore using various methods. The two predominant methods are pyrometallurgy and hydrometallurgy ,

2958-723: The world's largest underground copper mine, located in the Chilean Andes . Founded by William Braden and E.W. Nash of New York City, the Braden Copper Company had started mining there in 1906. In Utah, the Bingham and Garfield Railway opened in 1911 to transport local ore, replacing the Denver and Rio Grande Railroad 's line. In 1936, Kennecott acquired all the assets of the Utah Copper Company. During World War II , Bingham set new world records for copper mining and produced about 30% of

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3016-485: Was a disaster at El Teniente mine, resulting in the deaths of 355 men and injury to 747 more. It was the largest mining accident in Chilean and has the highest death toll in world history associated with metal extraction. Some 1,000 miners were down in the pits when the fire started in a nearby warehouse. Dense smoke spread in the underground tunnels. Most of the dead and injured suffered carbon monoxide poisoning . Emergency exits were not well marked. In Chile, this incident

3074-530: Was a center of strong mineralization and structural weakness before the pipe was formed." Copper mineralization and pipe formation occurred in the Pliocene . Ore was originally mined from the Fortuna orebody at the southwest quadrant starting in 1906. Since 1922, the larger Teniente orebody has also been mined on the east side. "The best grade of ore is found in altered andesite or in andesitic flow breccia adjacent to

3132-496: Was established by Rio Tinto in April 2001 to develop surplus mining land. Daybreak Community , the first part of the process, is situated on 4,126 acres (1,670 ha; 16.70 km ) in the city of South Jordan where 20,000 homes and up to 14,000,000 square feet (1,300,000 m ) of commercial space are planned. Opened in 2009, Daybreak's first commercial center, SoDa Row , contains a boutique, restaurants, hair salon and more. During

3190-443: Was formed in 1989. The mine and associated smelter produce 1% of the world's copper. Utah Copper Company had its start when Enos Andrew Wall realized the potential of copper deposits in Bingham Canyon, 15 miles (24 km) southwest of Salt Lake City , Utah in 1887. He acquired claims to the land and started underground mining. In the mid-1890s, metallurgist Daniel C. Jackling and mining engineer Robert C. Gemmell inspected

3248-498: Was interrupted from 1985 to 1987. In 1986, Asarco purchased the Ray mine in Arizona from Kennecott. In 1987, British Petroleum acquired SOHIO, and Kennecott became part of BP Minerals America. In 1989, Rio Tinto Zinc (RTZ) purchased mining assets from BP. Kennecott Utah Copper Corporation was formed by Rio Tinto in 1989 as a new mining company under the laws of the State of Utah. Today,

3306-475: Was mined manually in what would be called the Fortuna sector, and transported out of the mine by pack animals , such as ponies and mules. It was worked until 1897, when the high-grade ore was exhausted. In 1904 William Braden (an engineer from New York City , United States) and E.W. Nash formed the Braden Copper Company . They built a road for carts and a concentrating plant, which was in operation by 1906. In June 1910, Guggenheim Exploration took control of

3364-545: Was named president, Spencer "Speck" Penrose was named secretary-treasurer, and Jackling was named general manager. The company immediately started a pilot mill at Copperton . With financing from Guggenheim Exploration , the first digging began in 1906. The same year, the Kennecott Mines Company was formed in Alaska, named after explorer and naturalist Robert Kennicott . A smelter was also started at Garfield, Utah by

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