The Problem of Nuclear Power - Free Essay Example

History of Humans Discover and Use Nuclear Power The energy throughout humans history. The process of humans using the energy was distributed into five stages. From about millions of years ago, humans were starting to use fire. Then, humans use the natural power such as wind energy and animal traction. The next are fossil fuel, electric energy and nuclear energy. So far, nuclear energy is the newest and the efficient energy. The discovery of nuclear energy dates back to the end of the 19th century. In 1895, Wilhelm Konrad Rontgen, a German physicist, discovered the X-ray. In 1896, Antoine Henri Becquerel, a French physicist, discovered the radioactivity. In 1897, Joseph John Thomson, a British physicist, proved the existence of electron. In 1898, Marie Curie discovered the radioactive element polonium, and after four years, in 1902, Curie discovered the radium. In 1905, Albert Einstein proposed the mass-energy formula. In 1920, Ernest Rutherford, a British physicist, found that the hydrogen nucleus is a positive charge unit and denominate it as proton. In 1935, James Chadwick, a British physicist, discovered the neutron. In 1938, Otto Hahn, a German scientist, discovered the nuclear fission phenomenon by bombarding a uranium nucleus with a neutron. In 1942, the first nuclear reactor was activated in university of Chicago. Nuclear power was used in the weapon field first, in 1945, United States drop two a tomic bombs to Nagasaki and Hiroshima. In 1954, the first nuclear power station, Obninsk was built in the Soviet Union, which marks the first-time humans used nuclear energy peacefully. Soon, humans applied the nuclear energy to industrial, military, aerospace field and so forth. However, the utilization of nuclear energy also brings various problem. One of the biggest problems is the pollution. Nuclear Power Nuclear power is the use of nuclear reaction that release nuclear energy to generate heat and the reaction accord with the mass-energy formula [Hewitt, Paul G, 2016]. Nuclear energy can be released by three nuclear reactions, which are the nuclear fission, nuclear fusion and nuclear decay. Nuclear Fission Nuclear fission is a reaction that a nucleus splits into many nucleuses and releases a very large amount of energy with this reaction. Only very massive nucleus can produce the nuclear fission such as U, Th and Pu. If all the nucleuses in one-kilogram U238 produce fission, they can generate 20000 MW hours energy, which is equal to the energy of combust 2000-ton coal. There are two types of nuclear fission. One is without the incoming neutron, which is kind of radioactive decay and was described as spontaneous fission. However, this kind of fission only exists in a few heavier isotopes such as U235. Most of the nuclear fission is a nuclear reaction with neutron bombardment. For example, neutrons hit the uranium atoms; the uranium atoms break apart and create heat and new neutrons; these new neutrons keep hitting other atoms continually. This process was described as chain reaction. In addition, nuclear fission is the energy source of nuclear power station. Nuclear fission also was used in the atomic bomb. The explosion of atomic bomb is a chain reaction that out of control. Nuclear Power Station The difference between nuclear power station and atomic bomb is the chain reaction was controlled or not. In order to control the nuclear chain reaction, the reactor operators use control rods. The raw materials of control rod are something can absorb neutrons such as boron, Boron carbide and cadmium. The key equipment of nuclear power station is nuclear reactor. Nuclear reactor groups into fast neutron reactor and thermal neutron reactor, graded by the energy of the neutron that cause fission. The energy of thermal neutron is about 0.1eV and the energy of fast neutron is about 0.2eV. The running equipment is thermal neutron reactor. In the reactor, the fast neutron crash into the atom of moderator. Then fast neutron was slowed down and becomes thermal neutron. The moderator can be water, heavy water, graphite, etc. The reactor also needs coolant to carry out the heat. The coolant can be water, heavy water, helium, etc. Based on different moderator, coolant and fuel. Thermal neutron reactor can be divided into light water reactor (use light water as the moderator and coolant; use enriched uranium as fuel), heavy water reactor (use heavy water as the moderator and coolant; use enriched uranium as fuel) and light water graphite reactor (use graphite as moderator; use light water as coolant; use enriched uranium as fuel). Nuclear fission is the only nuclear reactor that humans can control. Nuclear Fusion   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Nuclear fusion is a reaction that light nucleuses (such as deuterium and tritium) combine into a more massive nucleus (such as helium) and releases a very large amount of energy with this reaction. Reacting nuclear fusion must meet two condition: ultra-high temperature and high pressure. Normally, there are two ways to react a controllable nuclear fusion. Inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). Located in California, the National Ignition Facility is the biggest laser fusion device in the world and it is kind of the ICF. Examples of Nuclear Fusion One of the most common nuclear fusion is the Sun. The Sun releases heat and light by reacting nuclear fusion. The temperature in the middle of the Sun is about 15 degrees. And the air pressure of the Sun is 300 billion atmospheres. Therefore, nuclear fusion can react on the Sun. Another common nuclear fusion is hydrogen bomb. Hydrogen bomb is kind of nuclear weapon and causes damage by energy that when hydrogen isotopes reacting nuclear fusion generates.   Compare to Nuclear Fission Advantages: (1) The energy that nuclear fusion generates is far more than nuclear fission generates. (2) Nuclear fusion will not produce nuclear waste, it is environment friendly. (3) The fuel of nuclear fusion is sufficient. There are 10 trillion of deuterium in the world. Therefore, nuclear fusion energy is an inexhaustible new energy.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Disadvantage: Nuclear fusion requires harsh terms and high technology [Robert L. Hirsch, 2015]. Hence, humans cannot control nuclear fusion very well. Nuclear Decay   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Nuclear decay (also known as radioactive decay, radioactivity or nuclear radiation) is the process by which an unstable atomic nucleus loses energy by emitting radiation. This process occurs spontaneously by nucleus. There are three common kinds of nuclear decay. ? ±-decay (an atomic nucleus emits an alpha particle and thereby transforms into a different atomic nucleus, with a mass number that is reduced by four and an atomic number that is reduced by two). -decay (a beta ray and a neutrino are emitted from an atomic nucleus, but the mass number does not change). -decay (After ? ±-decay or -decay, the atomic nucleus is in excited state. Then, this atomic nucleus transforms to ground state and emits -ray) The Problem of Nuclear Power The nuclear power brings a big amount of energy to humans, but it also brings many problems. One of the most serious problems is nuclear waste material. Nuclear waste material is waste that contains radioactive material and was produced by processes that nuclear fuel production, nuclear fuel processing and reaction in a nuclear reactor. The nuclear waste material has three features, which are radioactive, radio-hazard and release heat. The radiation of nuclear waste material couldnt eliminate by physical, chemistry or biology ways and only could reduce by self-decay. When the ray that nuclear waste material emits passes through an organism, ionization and excitation effect are happened and cause radiation damage. The radioactive nuclide in nuclear waste material releases heat throughout decay; the temperature of the nuclear waste material keeps increasing because of the heat; even makes the waste solution boiling and waste solid melting. As a result, the nuclear waste material is harmful. Safety also is a problem that cannot be ignored. Producing nuclear energy needs to process chain reaction of nuclear fission. Once the reaction out of control, nuclear leakage is happened and generates big amount of neutron and radioactive material which are detrimental to humans and environment. There are a few of nuclear leakage accidents have taken place around the world. The most serious and famous accidents in the world is the Chernobyl Disaster, which happened in April 26, 1986. In addition, in March 12, 2011, Fukushima Nuclear Power Plant in Japan took place nuclear leakage accident because of the earthquake. So far, radioactive material still affecting the local environment. In conclusion, improve safety of nuclear power station is very important. A minor issue is that nuclear fuels are limited [Kessler, G. (Gnther), 2012], humans must develop new energy before nuclear fuels run out. Solutions When we are enjoying the gift from nature, we should be responsible for protecting nature, or we will be severely punished. Currently, the solution of dispose of nuclear waste are sink the waste into the sea and bury the waste underground. In Guangdong province and Gansu province, China, people have been built two disposal sites and used for disposal of low and intermediate level radioactive solid wastes. However, these solutions only the stopgap measure, not long-term solutions. A new solution was coming up with, that is send the waste to the space. If the waste flutters in space or fall into the Sun, it will not do harm to environment. However, how to send the waste to the space is still a problem. In order to solve the problem that nuclear fuels will run out, humans are developing nuclear fusion. Once nuclear fusion is controlled, humans will have unlimited nuclear fuel that come from sea. Conclusions We should be grateful to all the scientist that make a great contribution to develop nuclear power. Nuclear fission is a reaction that a nucleus splits into many nucleuses and releases a very large amount of energy with this reaction, and which was discovered by Lise Meitner and Otto Hahn. In addition, nuclear fission is the energy source of nuclear power station. Nuclear fusion is a reaction that light nucleuses combine into a more massive nucleus and releases a very large amount of energy with this reaction and which was discovered by Mark Oliphant. Nuclear fusion is a direction for development of nuclear power. Nuclear decay is the process by which an unstable atomic nucleus loses energy by emitting radiation and which was discovered by Antoine Henri Becquerel. Although there are so many problems of nuclear fission, such as the nuclear waste material, safety of nuclear power station. However, humans also figure out how to solve these problems, and try hard to develop nuclear fusion. I believe humans will get more achievement in nuclear power field in the future. References Kessler, G. (G?nther). Sustainable and safe nuclear fission energy: technology and safety of fast and thermal nuclear reactors.; Springer Berlin Heidelberg, 2012. Hewitt, Paul G. Focus on Physics.; Science Teacher, 2016. Robert L. Hirsch. Fusion Research: Time to Set a New Path.; Issues in Science Technology, 2015. Figure 1. Chain reaction [Kash Farooq, 2011] Figure 2. Scheme of typical Boiling Water Reactor [Igor Pioro, 2013] Figure 3. Nuclear Fusion [J.K. Shultis, R.E. Faw, 2002] Figure 4. ? ±-decay [Wikimedia Commons, 2007] Figure 5. -decay [Wikimedia Commons, 2007] Figure 6. -decay [Wikimedia Commons, 2007]