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Uranium

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Mitchell McLinton

on 24 October 2014

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Transcript of Uranium

Case Study of Uranium
This article details the morality and ongoing debate on whether Australia should continue its deal and export Uranium to India. Since the Fukushima disaster (Australia supplied Uranium to Japan), Australia has been in an internal debate about whether to export Uranium, as Australia has a moral obligation and a humanitarian responsibility for the hazards posed by the Uranium it sells. Additionally, Australia has made an agreement to only sell Uranium to countries that were signatories to the nuclear non-proliferation treaty. This is especially the case with India, as they are currently in a border war with Pakistan, it means that Australia would violate the long standing position of adhering to international treaties.
Ethical Views Surrounding Uranium Mining
There are many socioeconomic views both for and against uranium. I will highlight some key points for both for and against uranium mining, and then provide my own opinion on the matter.
Implications of Uranium
As said earlier, there is essentially one purpose for the mining of Uranium, the use of it in fission and fusion reactors. It, contrary to popular belief, is probably the
cleanest
and most efficient form of power generation. Unless there is a reactor meltdown, Nuclear power produces the least amount of unusable waste product. However, if the reactor does go through a meltdown, very large quantities of radioactive particles can be spread throughout the area, endangering the greater society through cancers and deformities (cancer is more likely) due to the radioactivity. But now, due to the Japanese Fukushima Nuclear Disaster in 2011, many countries are beginning to reconsider other power options, and some countries may be terminating their Nuclear power programs
In conclusion, the use of nuclear reactors to provide power to cities in the world is very good, and uranium mining itself is very beneficial to the economy. Nuclear power and uranium mining both have to be managed in a way that is not damaging to the environment, and will not endanger people's lives.
An Investigation into the Socioeconomic Implications and Prospecting Processes of Uranium

'The Guardian' from whom the article originated states that:
'We should be wary of selling Uranium to a nation that will not sign the non-proliferation treaty and refuses to decommission its nuclear weapons...'

Exporting Uranium to India would mean facilitating their Military Nuclear Program, which is something the government does not want to do. In fact, due to the Fukushima disaster, many countries in the world are reconsidering Nuclear power, and nuclear energy is facing a structural decline.

'With the horror of Fukushima still clearly visible, the morality of exporting Australian uranium to India is on shaky ground indeed.'
Link
http://www.theguardian.com/environment/southern-crossroads/2014/sep/29/australian-uranium-india-fukushima
Description of Uranium
Uranium is in the Actinides category of the periodic table, it is element number 92, the last naturally occurring element on the table.
Contrary to popular belief, Uranium is a silvery white metal, that is weakly radioactive due to the fact that its isotopes are relatively unstable.Its atomic mass is 238.03, with approximately 92 protons, 146 neutrons, and 92 electrons, 2 of them being valence electrons.
Uranium was discovered in 1789 by Martin Klaproth. It was named after the planet, Uranus and is commonly used for fuel in nuclear reactors. It also has a history of being used in weapons of mass destruction.

There are 10 known isotopes of Uranium (U-230 to U-240), ranging in half-lives of 23.5 minutes (U-239) to 4.5 billion years (U-235).
Uranium is mined in multiple locations throughout the world, with Australia having the most (31%) of the Earth's Uranium reserves. Kazakhstan, Canada and Australia account for 61% of the world's Uranium production, with other countries such as the US, Russia and China (etc.) producing at least 1,000 tonnes per year.

There are mainly 3 types of uranium deposits (although there are many more), those in sedimentary rock, those in igneous rock, and those in hydrothermal rock. Deposits in sedimentary rocks are in Canada, the US and Australia, although there is one in South Africa. Deposits in Greenland and Namibia are the igneous and hydrothermal deposits.
There are 3 main methods of mining Uranium, they are
underground
mining,
open pit
mining, and
In-situ leaching
(ISL).

Underground mining causes very little environmental damage, but is relatively expensive. It is used when the Uranium deposit is too far below the surface (crust of the Earth) to be mined using Open pit mining. Tunnels and shafts are dug to access and remove Uranium ore, the main mining method used in tunnels and shafts is drilling.

Open pit mining causes the most environmental damage, but is the least expensive method of mining. It is used when the Uranium deposit is not too far below the surface (crust of the Earth) and can easily be accessed by removing overburden (termed as waste rock in the mining industry) through drilling and blasting. The deposits are then also mined by blasting and excavated using large dump trucks and loaders.

ISL causes the least environmental damage, but is by far the most expensive method. It involves leaving the ore where it is in the ground, but dissolving the ore and pumping the solution to the surface, where it can be recovered.
Uranium is generally mined for one purpose only, fuel in nuclear reactors. It does however, have a history of being used as a weapon of mass destruction, examples of this being in the Cold War (1947 - 1991)
Glossary of Terms
Actinides: The series of elements that are all radioactive, starting with Actinium and ending with Lawrencium
Element: A class of substances that cannot be separated into simpler substance via chemical means
Radioactive: Pertaining to the phenomenon that an element or object spontaneously emits radiation resulting in changes in the nuclei of atoms of an element.
Isotope: One of two or more atoms that have the same atomic number, but different numbers of neutrons
Atomic Mass: The mass of an element/isotope measured in the units of protons and neutrons
Protons: A positively charged elementary particle that is a fundamental constituent of all nuclei
Neutron: An elementary particle having no charge, mass slightly greater than that of a proton, constituent of all the nuclei of atoms, excluding Hydrogen
Electron: A negatively charged elementary particles that is a fundamental constituent of matter
Valence Electron: Electrons in the outermost electron shell of an element
Electron Shell: The orbit of electrons around the nuclei of an atom
Nuclei: Centre of an atom, where the protons and neutrons are located
Half-Life: The time required for one half the atoms of a given amount of a radioactive substance to disintegrate
Sedimentary Rock: Rocks formed by the deposition of material at the Earth's surface and within bodies of water
Deposition: The state of being deposited
Igneous Rock: Rocks that are formed by the cooling and solidifying of molten materials (magma, lava)
Hydrothermal Rock: Rocks that have been crystallized from hot water, or have been altered by hot water passing through them
In-situ Leaching: The act of 'leaching' minerals by dissolving them, and pumping out the pregnant solution to the surface.
Overburden: Waste rock (not the mineral) that is usually over a mineral deposit; pertaining to open pit mining
Fission: Also called Nuclear fission; the splitting of the nucleus of an atom into nuclei of lighter atoms, accompanied by the release of energy, example would be the fission of U-236 which splits the atom to form a Kr atom and a Ba atom
Fusion: Also called Nuclear fusion; a thermonuclear reaction in which nuclei of light atoms join to form nuclei of heavier atoms, as the combination of deuterium atoms to form helium atoms
Kr: Krypton
Ba: Barium
Deuterium: A hydrogen isotope, having twice the mass of an ordinary H atom
H: Hydrogen
Reactor Meltdown: Informal term for a severe nuclear reactor accident that results in core damage from overheating
Fukushima Nuclear Disaster: A INES class 7 (major) Nuclear disaster, where 3 of the plant's six reactors went into meltdown due to a tsunami triggered by a magnitude 9.0 earthquake (2011)
INES: International Nuclear Events Scale
Non-Proliferation: Not spreading or making excessive use of
Gas Centrifuge: A centrifuge that performs isotope separation of gases
Hydrofluoric Acid: HF, a corrosive liquid, made up of Hydrogen and Fluorine, chiefly used in etching glass
Uranium Hexafluoride: A colourless, volatile solid (UF6 [6 subscript]) that in gas form is used in refinement of uranium.
Ionic Bonding: Bonding between metal and non-metal (periodic table), results in an equal share of electrons, resulting in a neutral compound.
Due to the fact that Nuclear power is extremely efficient, many countries like to use it for public power usage. Thus, the demand for Uranium is extremely high, with many countries around the world always in demand. And due to that, countries that have Uranium deposits often can generate high amounts of income, by producing it for other countries. An example of this would be Australia, although Uranium mining is slowly being abandoned in Australia, in 2007-8, the all time high of the amount of money they made in Uranium exports was a total of USD$70 million. This shows that countries can make ludicrous amounts of money in the Uranium mining industry alone. Additionally, if Australia were to continue their Uranium mining program, they would dominate the entire mining business, due to their large deposits of minerals.
Before 2011 (more specifically the Fukushima Nuclear Disaster), the demand for Uranium was gradually increasing, to the point where the most major countries around the world were all in demand for Uranium as a fuel source. However, due to the Fukushima Nuclear Disaster, the demand for Uranium is now gradually decreasing, as many countries around the world are shutting down their Nuclear power programs, and reconsidering other power programs, such as geothermal, hydro, and wind etc.


Brain, Marshall . 2006. HowStuffWorks (What's a Uranium Centrifuge?). [ONLINE] Available at: http://science.howstuffworks.com/uranium-centrifuge.htm. [Accessed 18 October 14].
United States Government Officials. 2014. NRC. [ONLINE] Available at: http://www.nrc.gov/materials/fuel-cycle-fac/ur-enrichment.html. [Accessed 18 October 14].
Dictionary.com. 2009. Dictionary.com. [ONLINE] Available at: http://dictionary.reference.com/. [Accessed 23 October 14].
David Thorpe,The Guardian. 2008. Extracting a disaster. [ONLINE] Available at: http://www.theguardian.com/commentisfree/2008/dec/05/nuclear-greenpolitics. [Accessed 22 October 14].
Alexander White,The Guardian. 2014. After Fukushima, Is it morally correct for Australia to sell Uranium to India?. [ONLINE] Available at: http://www.theguardian.com/environment/southern-crossroads/2014/sep/29/australian-uranium-india-fukushima. [Accessed 18 October 14].
The Wikimedia Community. 2010. Uranium. [ONLINE] Available at: http://en.wikipedia.org/wiki/Uranium. [Accessed 10 October 14].
World Nuclear Association. 2014. Australia's Uranium Mines. [ONLINE] Available at: http://www.world-nuclear.org/info/Country-Profiles/Countries-A-F/Appendices/Australia-s-Uranium-Mines/. [Accessed 22 October 14].
World Nuclear Association. 2014. Australia's Uranium. [ONLINE] Available at: http://www.world-nuclear.org/info/Country-Profiles/Countries-A-F/Australia/. [Accessed 22 October 14].
'We should be wary of selling Uranium to a nation that will not sign the non-proliferation treaty and refuses to decommission its nuclear weapons...'
(The Guardian, Alexander White, 2014)
'With the horror of Fukushima still clearly visible, the morality of exporting Australian uranium to India is on shaky ground indeed.'
(The Guardian, Alexander White, 2014)
Refinement/Prospecting Processes of Uranium
There are multiple ways to refine Uranium ore, I however, will only highlight three of them in this presentation.

The first is likely the most basic and is the most common method, the use of a gas centrifuge to refine uranium.
To start with, we are attempting to get U-235 and U-238 from this refinement process, U-238 is the most common and has little use (99% of ore is U-238), U-235 is what we use to power nuclear reactors, and can be used to make bombs etc. The centrifuge exploits the weight different of the two isotopes. Firstly, we react the Uranium with Hydrofluoric Acid (HF), after several steps, we get Uranium Hexafluoride in gaseous form.

Now that we have the gas, we can put it into a gas centrifuge and begin the spin cycle, the centrifuge generates a force thousands of time more powerful than the force of gravity. U-238 atoms are heavier that U-235, so they move out to the walls of the centrifuge, it is vice versa for U-235, having the atoms move towards the centre of the centrifuge. This cycle only creates a slight difference in concentrations of U-235 and U-238, but it does have more U-235 than it did before. In order to create a gas enriched in U-235, we can put it through the centrifuge thousands of times. In Uranium enrichment plants, the thousands of centrifuges are chained together in long cascades.

After we meet a suitable level of concentration of U-235 in the gas, we need to turn the gas back into a metal, we do this through a process of ionic bonding, by adding Calcium, the Calcium reacts with the Fluorine to create a salt, and the pure Uranium metal is left behind. This enriched (in U-235) Uranium 'patty' can be used to power a nuclear reactor. It does have a use in bomb making, but since the Cold War, there are few nuclear weapons.
The second method I will highlight is Gaseous Diffusion. The diffusion process is done in a gaseous diffusion enrichment plant, and also makes use of the Uranium Hexafluoride gas. The gas is slowly fed into the plants pipelines where it passes through porous membranes, the holes in the filters are so small, that only a molecule at a time can pass through each hole. The separation of the isotopes occurs when the lighter molecules of the gas (ones with U-235) tend to diffuse faster through the barriers than the heavier molecules (ones with U-238). Similarly to the first method, where we want to get the most enriched gas, in order to have high concentration of U-235 molecules, we use hundreds of barriers to separate the isotopes from each other. At the end of the cycle, the gas is pumped out and allowed to solidify, until being exported to Nuclear power plants around the world/country. The diagram below details the process.
'The gaseous diffusion process uses molecular diffusion to separate a gas from a two-gas mixture. The isotopic separation is accomplished by diffusing uranium [which has been combined with fluorine to form uranium hexafluoride (UF6) gas] through a porous membrane (barrier), and using the different molecular velocities of the two isotopes to achieve separation.' (Picture and explanation courtesy of www.nrc.gov)
The final process which I will detail is likely the most expensive and least common of the three. Laser separation. Separation of isotopes can be achieved using laser light by using it to excite the molecules (based on something called the 'photoexcitation principles'). The technologies surrounding laser separation of isotopes has been aptly names Atomic Vapour Laser Isotope Separation (AVLIS), Molecular Laser Isotope Separation (MLIS) and Separation of Isotopes by Laser Excitation (SILEX). AVLIS uses Uranium-Iron (U-Fe), MLIS and SILEX use the common Uranium Hexafluoride.

The lasers can be tuned to deliver a light of a single-colour, the unique radiation given off by this light can photoionize a certain isotope, leaving the other isotopes alone (in short, we can use a light to only excite the U-235 molecules, leaving U-238 and U-234 etc. molecules alone). The affected product is then chemically changed to allow for separation.

'The gas centrifuge process uses a large number of rotating cylinders in series and parallel configurations. Gas is introduced and rotated at high speed, concentrating the component of higher molecular weight toward the outer wall of the cylinder and the lower molecular weight component toward the center. The enriched and the depleted gases are removed by scoops.' (Picture and explanation courtesy of www.nrc.gov)
For Uranium Mining
First things first, Uranium is the cleanest and most efficient source of energy that we currently known of. Nuclear reactors emit less greenhouse gases than burning any form of fossil fuel, additionally, 1 reactor can produce a large amount of electricity (much more than one coal generator plant) per 'tick'. This means that Nuclear power is very environmentally friendly, and is the best form of energy. As 1 in every 6500 molecules of seawater is deuterium (isotope of hydrogen), and deuterium can also used in fusion reactors, experts believe that due to the plentiful amounts of seawater on our Earth, fusion energy could supply the world with enough energy for at least a billion years. Therefore proving that Nuclear energy is extremely efficient.

Another advantage of mining uranium are the economic benefits, from 2000-2005, uranium mining in one of Australia's many uranium veins (Kakadu), brought US$1.844 million to the economy
alone
. This shows us that uranium mining is an excessively profitable business, due to the large demand of uranium for power all over the world. If a country such as Australia were to fully maximize the use of their uranium veins, they could easily generate large amounts of capital for the government and economy, which thus leads to improvements in general society. Additionally, the Jabiluka mine in Australia (on Aboriginal soil) has already generated US$4.5million, and is expected to generate a further US$175 million for the economy over the mine's lifespan.


Against Uranium Mining
Hundreds of cases have been submitted against governments to stop the mining of Uranium. There are multiple reasons for this, the first is that Nuclear power is extremely dangerous, emitting high levels of dangerous radiation if not handled carefully. As such, many people around the world are encouraging the prevention of uranium mining and nuclear reactors . There are a myriad of ethical reasons for why we should not utilise Uranium and Nuclear power, the ones I will highlight are the health and safety concerns, and the environmental outlooks.

Firstly, there are many health and safety concerns surrounding the mining and use of uranium. An example of this would be both Chernobyl and the Fukushima disaster of 2011, due to the reactor meltdowns that occurred in these cities, Nuclear radiation became a serious health concern (still is in Chernobyl). The diseases that can occur from radiation are mainly cancers, a very serious disease. Radiation can also occur from contact with uranium, or the particle waves it gives off. The main health concern that is associated with nuclear power is the possibility of a reactor meltdown, there are many things that can go wrong in a Nuclear reactor. The main health concern that is associated with the mining of uranium is the radiation that is given off by the ore.
Countries, such as Australia, are also partially responsible for the things that are done with the uranium that they export, for example, as said earlier, Australia do not want to encourage the use of Uranium in a border warring country such as India, as they feel that they will be partially responsible for what is done with that Uranium.

Next, their are an insane amount of environmental concerns that come with Nuclear power/uranium mining. Yet again, radioactivity is one of the main concerns here, a radioactive area ensures that no life can live their. An example of this is yet again Chernobyl, due to the insane amounts of radiation there, no life cannot and will not live there for likely the next 2000 years. Additionally, the act of mining uranium can cause amounts of radiation to leak to the surface, the mining of uranium can damage the landscape, especially open cut mining, which removes an entire 'box' of land, along with animal habitats. Water supplies, surrounding nuclear power plants or enrichment facilities can easily become contaminated, resulting in many animals dying.

As a combination of both, a few countries that have not signed the 'Nuclear Non-Proliferation Treaty' could make use of nuclear bombs, warheads etc as weapons of mass destruction. In fact, North Korea, a very hostile country, are not signatories to the treaty, and commonly develop nuclear weapons. The use of nuclear weapons in an area can result in death to all surrounding life, an inability to live there for many years to come, and the possibility of a fallout. The sheer horribleness of nuclear weapons is demonstrated in the WW2 bombings of Hiroshima and Nagasaki, millions of Japanese people were killed in the bombings and the areas were rendered highly radioactive causing even more to become sick and eventually die.
Opinion
By comparing both the good and bad points that surround the mining and use of uranium, I have come to an opinion that is neither for or against. Although we have seen, and I believe, that uranium and Nuclear power are two very dangerous things, I also believe that uranium mining and nuclear power are very good for the economy, and can be managed in such ways that it is safe. This is because, we have observed that for a nation mining is very profitable and can generate large amounts of capital, seen in Australia. If countries were to mine uranium and export it, they would generate large amount of money for themselves, boosting the nation's economy. Secondly, Nuclear power is very efficient, and can be used very well to power entire cities, countries could also sell their power to countries that do not have the means of utilising nuclear power.

However, the overall effects of uranium mining (which leads to eventual use of it in nuclear power) have been seen to have cataclysmic effects on our world today (Fukushima, Chernobyl, Nagasaki etc.), having many large effects on both our health and all environments (urban and natural) today. As such, I believe that unsafe and untrained usage of nuclear reactors is extremely dangerous, and any countries that do not have allies to help them with nuclear power programs should not be dabbling in any sort of nuclear physics/engineering projects.

Although this is slightly unrelated to the context we are talking about here (which is uranium mining for the use of it in reactors), it does pertain to uranium mining as a whole. The use of uranium as a weapon of mass destruction, although this has already been outlawed, I feel that uranium weapon research should be banned and illegal as a whole. A few countries, such as Russia and the United States of America, still research nuclear weapons, this means that they could possibly utilize these weapons in future wars, and although it violates an International Treaty, a country that has access to nuclear weapons may violate it for the purpose of winning battles in the war. Consequently, nuclear weapons are excessively devastating to the environment and people's health, a nuclear meltdown alone can endanger millions of lives, who knows what a fully capable nuclear bomb could do?
Sir Richard, H (2014, October 17) Personal Interview
Sir D***D, M (2014, October 22) Personal Interview
Calcium: Ca, a silvery white metal used in various things but (for us) mainly a necessary element in nerve conduction, bone strength etc.
Fluorine: F, most reactive non-metal, usually found in other substances such as fluorite, corrosive
Gaseous Diffusion: The passage of gas through microporous barriers, a technique used for isotope separation, especially in the preparation of fuel for nuclear reactors.
Photoexcitation Principles: The principles of the photoelectrochemical processes of electron excitation via the absorption of protons; absorption pertains to Planck's Quantum Theory
Planck's Quantum Theory: Pertaining to quantum mechanics, Quantum theory is the theoretical basis of modern physics that explains the nature and behavior of matter and energy on the atomic and subatomic level.
Photoionize: Ionization of a molecule/atom via the absorption of radiant energy
Ionization: Process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes.
Capital (economics): Assets remaining after deduction of liabilities; money currently held by a company or government
Bibliography
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