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Bauxite and Aluminum: A Cradle to Grave Analysis

Bauxite and Aluminum: A Cradle to Grave Analysis

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Bauxite and Aluminum: A Cradle to Grave Analysis

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  1. Bauxite and Aluminum: A Cradle to Grave Analysis By Greg Zelder and Sebastian Africano Race, Poverty, and the Environment Professor Raquel R. Pinderhughes Urban Studies Program San Francisco State University Spring, 2003 Public has permission to use the material herein, but only if author, course, university, and professor are cited

  2. This presentation focuses on the extraction and refinement of Bauxite, followed by the production, consumption, and disposal of Aluminum. It is designed to enhance the readers’ awareness of the realities behind aluminum consumption by examining the effects of its production on the people and environment of the planet. It takes you through the cradle to grave lifecycle of aluminum, paying particular attention to the social, environmental, and public health impacts of the processes associated with producing it.

  3. Contents, Part I, slides 4 - 47 • Geology • History of Bauxite Use • Social Impacts of Bauxite Mining • Case Studies • India • Haiti • General Impacts of Bauxite Mining • Environmental Impacts of Bauxite Mining

  4. Contents Part II, slides 48 - 85 • Distribution of Bauxite • Aluminum Smelting Inputs & Processes • Spent Pot Lining (SPL) • Energy and Resource Use in Al Smelting • Aluminum Smelter Emissions • Exposure to Fluorides • Exposure to Aluminum • Aluminum in Food and Water • Aluminum in Medicine • From aluminum Metals to Consumer Products • Aluminum and Recycling • Conclusion

  5. Geology of Bauxite Bauxite ore is the most abundant element found in the earth's crust, although the word bauxite is used to describe any material that contains more than 32 percent alumina1. A Bauxite rock with impurities

  6. Geology of Bauxite • Dislodged rock particulates in areas of heavy rainfall percolate down to the water table, where aluminum silicate compounds accumulate and pressure causes them to coalesce. • In this form the compounds are what we consider bauxite2.

  7. Geology of Bauxite • There are three main structural types of bauxite: • Gibbsite • Böhmite • Diaspore • Each of these three types of bauxite has different characteristics that make them more or less desirable for mining purposes.

  8. Geology of Bauxite • Gibbsite has a maximum alumina content of 65.4% • Böhmite and diaspore both have a maximum alumina content of 85%3. • Of the bauxites currently being mined, the dominant form is gibbsite, followed by a mixture of gibbsite and böhmite. • The main impurities are compounds of iron, silicon and titanium4.

  9. Geology of Bauxite • The three structural differences of Bauxite can be further categorized into two groups, the difference being in the water content of each5 : • Monohydrates • trihydrates • Trihydrates are comprised of gibbsite and böhmite and are found in Latin America and Caribbean areas6. • Deposits of desirable bauxite occur as flat layers lying near the surface and may cover many miles - the average thickness of these layers is 4-6 meters7.

  10. History of Bauxite Use • Bauxite was used long before it was ever refined into aluminum. • In Guyana it was used to build homes with the so-called "brown-mud" that would later be called bauxite. • These deposits were also used to make pots and plates, along with using it as a plaster for homes8 .

  11. History of Bauxite Use • It was not until 1825 that western cultures devised a way to make aluminum from bauxite. The Danish Chemist, Hans Oerstad was able to isolate a small amount of aluminum from bauxite9 . • Over the next few decades new procedures were introduced that lowered the cost of aluminum, however it was still used only for jewelry purposes10 .

  12. History of Bauxite Use • It was not until 1886 that the Hall-Heroult electrolytic process, which is used to make aluminum from alumina, was discovered. • In 1889 Karl Bayer introduced the Bayer process of extracting mass amounts of alumina from bauxite11 .

  13. History of Bauxite Use • Four to six tons of bauxite are needed to produce two tons of alumina which in turn produces one ton of aluminum12 . • In 1998, the total area mined for bauxite was 1591 hectares (3929.77 acres) of which 80% was wildlife habitat, 175 hectares (432.25 acres) was tropical rainforest and 577 hectares (1425.19 acres) possessed important fauna species13.

  14. Alumina Production According to Persaud, in the Bayer Alumina reduction process: • "The bauxite is first ground and mixed with chemicals (sodium hydroxide/caustic soda, lime). Then it is pumped into huge pressure containers and heated, after which more chemicals (lime to regenerate caustic soda) are added, and hydrated alumina crystallizes from the solution after being seeded with other (trihydrate alumina) crystals. These crystals are then washed and heated at very high temperatures to drive off the moisture until a white powder remains. This is the alumina or aluminum oxide14,15”

  15. Alumina Production, cont…. • The OSHA filed Material Safety Data Sheet for Caustic Soda lists it as a highly reactive alkaloid dangerous to human health. • Effects of exposure to Caustic Soda: • ACUTE OVEREXPOSURE: Corrosive to all body tissues with which it comes in contact. • CHRONIC OVEREXPOSURE: Chronic local effect may consist of multiple areas of superficial destruction of the skin or of primary irritant dermatitis. • Inhalation of dust, spray or mist may result in varying degrees of irritation or damage to the respiratory tract tissues and an increased susceptibility to respiratory illness16.

  16. Alumina Production, cont… Courtesy of:

  17. The World's Bauxite Sources Courtesy of:

  18. Social Impacts associated with Bauxite Mining …the social impacts of bauxite mining and production are harder to quantify. • One must look at the societies that were living in bauxite rich areas before mining started, and also what happened to those societies after the development of a mining operation. • In many cases, the societies that were living on the land that was found to be rich in bauxite were indigenous cultures that had lived on the land for centuries prior to the discovery.

  19. Social Impacts associated with Bauxite Mining • Upon the discovery of bauxite, however, the people and cultures that relied on the land were displaced at the hands of the government. • Young people were forced to go to urban areas to make a living for the families, the land previously depended upon for agriculture was ravaged, and basically the fabric of the cultures was torn apart.

  20. Social Impacts associated with Bauxite Mining • How and why does this happen? • Is it necessary? • What is the role of the governments in these situations? To answer these questions one must look at specific cases.

  21. Case Study: India • In India the "problem" of indigenous cultures occupying bauxite-rich land has become a flash point of violence among the population and government. • In 1998 the Norwegian company Norsk-Hydro found bauxite in Orissa, a state in India. The problem for the company was that 2100 families in 24 villages stood in the way17. • Out of Orissa's 32 million people, seven million are aboriginal, and are concentrated in the mineral-rich Raigada, Koraput and Kalahandi districts where they make up 80 percent of the population18.

  22. Case Study: India • In Orissa alone there are nearly 150 million acres of once arable or homestead land that is currently being mined and there are an estimated 50,000 environmental refugees19. • Tribal or aboriginal people in India only make up 8 percent of the population but account for more than 40 percent of it's displaced people20.

  23. Case Study: India • In India the tribes, not the central government, control tribal land. This means that the tribes must decide whether the mining companies can be allowed to mine. • A local environmental group in the area organized a poll that showed that 96 percent of the people in the district were against the bauxite project21 .

  24. Case Study: India • The police in the area have taken up arms against the local people, apparently working for the company's interests, and have arrested nearly every land owner at least once and pressured them to sign away their lands22 .

  25. Case Study: India • In December of 2000 there were riots against the company and their plans to mine the region, in which two men were killed by police23 . • Human rights organizations believe that Norsk-Hydro was complicit in the killings because as the police have pressured the local people to sign away their lands, they have essentially become an unofficial subsidiary of the corporation. • If the corporation is found to be complicit it would be in violation of principles one and two of the United Nations Global Compact24 .

  26. Case Study: India • Principle one of the Compact states that corporations agree “to support and respect the protection of international human rights within their sphere of influence” • Principle two requires corporations “to make sure their own corporations are not complicit in human rights abuses.” 25

  27. Case Study: India • These allegations point to the larger problem of how large transnational corporations interact with local peoples in their quest for natural resources and raw material. • Local communities are not seen as being inherently needed by the country – rather, all that is seen is the negligence of the local people in not taking advantage of the resources that they own.

  28. Case Study: India • Because of this perceived negligence, foreign investors see the situation as one in which it is their duty to the global economy (not to mention their pocket books) that they exploit these areas. • In many cases the plight of the indigenous cultures are not taken into account by either the company or the government, leaving one to consider the interactions between the respective governments and corporations.

  29. Case Study: Haiti • Following the discovery of Bauxite in Jamaica in 1943, companies were looking into the possibility of bauxite being present in other Latin America islands. • In the summer of that year Reynolds Metals Company found bauxite in Haiti and proceeded to sign a concession contract with the Haitian government26 .

  30. Case Study: Haiti • Like most contracts between transnational corporations and governments of less developed countries, the contract was very one-sided in favor of the corporation. • The contract granted Reynolds “exclusive rights of privilege of making researches and of exploiting bauxite minerals and all other minerals containing or which may contain aluminum,” with practically the entire area of Haiti being specified27 .

  31. Case Study: Haiti • The agreement was to extend to 60 years after the signing, forcing the government to accept terms at an early stage of the bargaining process which may not have been suitable in the future. • The main factor behind the acceptance of these terms was the fact that the United States government gave support to Reynolds negotiations for two main reasons: • demand for aluminum had grown due to World War II and, • at the time, the U.S. government was trying to break the monopoly of Alcoa in the aluminum industry28 .

  32. Case Study: Haiti • Along with the “nudging” of the U.S. government, there were other reasons that the Haitian government believed that the contract would be good for the country: • Included in the contract was the promise of employment (even though the company only had to hire unskilled workers and no training for managerial or administrative positions was offered)29. • The country was to also receive a royalty payment tied to the production of bauxite - at the time the royalty amounted to 30.5 cents per 1000 kilos30. • In 1963 the contract was renegotiated and the royalty was actually lowered to 20 cents per ton31!

  33. Case Study: Haiti The government also believed that the company would add to the country’s infrastructure. • All the country received in terms of infrastructure was an 8-mile road connecting the mine to the port, which was only used to ship the refined alumina to the United States - the road had little effect on the economy as a whole32 . • The company also built a power plant, water supply infrastructure, and a hospital to be used by the company and it’s employees only33 .

  34. Case Study: Haiti • Along with these “oversights” by the government, the biggest, in relation to the population, was that the government agreed to help prevent strikes, creating an unsettling alliance to stop even the most basic forms of labor empowerment. • It is necessary to mention that the number of people employed by Reynolds was small in relation to the rest of the workforce (approximately 0.5%) of 45,000 workers34.

  35. Case Study: Haiti • This kind of agreement reinforces the notion of complicity when it comes to the dealings of governments, especially those in developing nations who are dependant on industrialization, and transnational corporations who have no accountability to the citizens of the countries in which they extract their resources.

  36. Impacts associated with Bauxite Mining • In the early days of bauxite mining, hydraulic strip mining was used to retrieve the bauxite35 • Hydraulic strip mining is the process of using high-powered streams of water to dislodge rocks and minerals that are then collected downstream. • This process is very damaging to the environment because of the large amount of silt that is created and that flows into nearby waterways.

  37. Impacts associated with Bauxite Mining • With time it was shown that a much more economically viable way of mining bauxite was to simply create an open pit where the bauxite, along with the surrounding materials could be hauled away36.

  38. Impacts associated with Bauxite Mining Courtesy of: Digging Up the Bauxite (Along with everything else)

  39. Impacts associated with Bauxite Mining Courtesy of: The Bucket from the previous slide

  40. Impacts associated with Bauxite Mining • Bauxite is now generally extracted with this method by removing the topsoil and then hauling away the 4-6 meters of bauxite underneath. • 80% of the world's bauxite is mined from blanket deposits where open-pit mining is used37. • The other 20% comes from Southern Europe and Hungary where underground excavation is utilized38.

  41. Impacts associated with Bauxite Mining • According to the industry, after the mining is completed the habitat is returned to its normal state…39. • This may be the case, but the original disruption is so great that one may wonder if it is possible to return a mined area to its “original” state.

  42. Impacts associated with Bauxite Mining • Because of the high alumina content of bauxite there is no need to use highly polluting procedures in the separation such as those in other industries (e.g. copper or iron)40. • The main pollutants that are released are caustic acids which, through spills or dumping, make their way to creeks and rivers and cause "fish-kill“, where "dead fish can be seen floating on the water,“41.

  43. Impacts associated with Bauxite Mining • The most noticeable impacts of mining and production is red-dust (sometimes referred to as red-mud). • Red-dust is mainly a by-product of the Bayer process, composed of the impurities in the bauxite that are not dissolved in the refining process. • The amount that is generated per ton of alumina produced varies between 0.3 tons to 2.5 tons, depending on the grade of bauxite used42 • Red-dust is non-toxic, although it is highly alkaline, but the lakes that it is stored in have been noted to produce a "harsh smell that is offensive and suffocating43“ • The dust is so fine that it "pollutes the air and finally settles in the most secret parts of homes,44"

  44. Impacts associated with Bauxite Mining • Recently an Australian researcher found a way to utilize red-dust in an ecologically sound manner. • Instead of just dumping the dust into specially formed lakes, he mixes it with seawater to make an alkaline sludge. • This sludge can then be used to "mop up" the heavy metals left in the tailings of other mining operations45.

  45. Impacts associated with Bauxite Mining • Another type of pollution that is produced by bauxite mining is noise pollution from all of the machinery that is needed and from the production facilities that run 24 hours a day46. • Most workers from the mines and production facilities live near their worksites with their families - the operations run incessantly, creating a near-urban racket in otherwise rural areas.

  46. Impacts associated with Bauxite Mining • Environmental damage also comes in the form of increased development. • In Haiti the Reynolds corporation built an 8-mile road from the production facility to the port, a power plant, water supply buildings and a hospital, not to mention housing for all of the workers, all in a very remote part of the tiny island-nation that hadn't been developed before47 . • The development disrupted major portions of the tropical forest surrounding the bauxite mine48.

  47. Impacts associated with Bauxite Mining • Generally speaking, alumina (Al2O3 - aluminum oxide) is the base input material used to make aluminum for all applications. • After all of the production of alumina is complete, it is shipped to industrialized nations where it is made into aluminum. • The shipping involves immense fossil fuel consumption and emissions and, less obviously, involves the transport of ballast water contaminated with foreign bacteria and sea life to the industrialized port destination, causing irreparable ecological harm.

  48. Distribution of Bauxite • After its production from raw bauxite, the powdered alumina is transported to a primary aluminum smelter. • Alumina produced in East Asia could be sent to a smelter in the Pacific Northwest – an ocean journey of 5000 miles. Alumina produced in Jamaica could be shipped to a smelter in Tennessee – a journey of only 1400 miles by comparison. • Different aluminum products call for varying compositional percentages of specific alloys, which could determine which plant receives what quantities of alumina, and from where.

  49. Below is a map of Alcoa’s Worldwide Operating

  50. Aluminum Smelting Inputs and Processes • Alumina (AL2O3 – Aluminum Oxide) is reduced to pure aluminum metal through the Hall-Heroult electrolytic process – named after its inventors. • The alumina is dissolved by passing an electric current between two nodes – a carbon anode (+) made of petroleum coke and pitch, and a cathode (-), the thick carbon lining of the electrolytic cell, or “pot”49. • The pot contains both the aluminum oxide powder and a molten cryolite-based electrolyte, sodium aluminum fluoride, which is used as the conductor of electricity50. • The electric current is passed between the two nodes, breaking the aluminum and oxygen bond of alumina, and leaving pure aluminum metal and oxygen – the latter which combines with the carbon anode to form CO2, which is released into the atmosphere51.