Реферат на тему Nuclear Energy Essay Research Paper Nuclear EnergyYou
Работа добавлена на сайт bukvasha.net: 2015-06-11Поможем написать учебную работу
Если у вас возникли сложности с курсовой, контрольной, дипломной, рефератом, отчетом по практике, научно-исследовательской и любой другой работой - мы готовы помочь.
Nuclear Energy Essay, Research Paper
Nuclear Energy
You are watching the control panels and gages for rector two. Sitting comely you think about how easy your job is. It is a joke! All day you sit around and watch the gages for reactor number two just to make sure they maintain their settings. You don’t even need to look at the gages either because a computer automatically regulates them without you. Life is so good. Suddenly all the sirens go of and the gages and displays spin wildly in every direction. The ground shakes and you can hear the sound of a deep rumble. Unknown to you, the reactor’s cooling pumps have failed to cool the reactor’s core and in 3 seconds the temperature went from 280 degrees centigrade to 4,000 degrees centigrade. The water that was in the reactor is instantly turned to steam which creates tremendous amount of pressure in the reactor core. Above the reactor core there is a 5 foot thick lead plate and above that there is a meter thick floor composed of iron, barium, serpentine, concrete, and stone. The exploding steam fires the floor up like shrapnel. The metal plate goes through the four foot thick concrete roof like butter and reaches and altitude of sixty meters. You can hear ripping, rending, wrenching, screeching, scraping, tearing sounds of a vast machine breaking apart. L. Ray Silver, a leading author who covered the disaster at Chernobyl, said that within the core, steam reacts with zirconium to produce that first explosive in nature’s arsenal, hydrogen. Near-molten fuel fragments shatter nearly incandescent graphite, torching chunks of it, exploding the hydrogen. The explosion breaks every pipe in the building rocking it with such power that the building is split into sections (11-13). You look down at your body and notice that it feels hot and your hands look different. Unknown to you a tremendous amount of neutrons are hitting your cells and taking chucks out of your skin. Suddenly everything goes black.
The paragraph above describes the scene of what happened at Chernobyl nuclear plant a few years ago. From that time until the present many other smaller accidents have happened. From these accidents many people have died and millions have been indirectly affected. Nuclear energy has far to many negative problems than advantages. From the mining of uranium to disposal of nuclear waist there are problems of such magnitude that no scientist on this earth has an answer for. Nuclear energy has so many problems associated to it that it should be banned from the earth.
To understand the threat of nuclear energy we must first understand what happens in a nuclear reaction. Ann E. Weiss, who has written several books on the subject of nuclear energy, described what happens inside a nuclear power plant. In a nuclear reaction the nuclei of its atoms split, producing energy in the form of heat. The heat makes steam which powers a turbine. Fission takes place in a nuclear reactor. The fuel used is pellets of uranium. In a modern reactor, half-inch long pellets of uranium are packed into 12 or 14 foot tubes made of an alloy of the metal zirconium. About 50,000 zircalloy fuel rods make up the reaction core. To control a nuclear reaction control rods made of cadmium is used which absorbs neutrons. With the control rods in place in the core, a chain reaction cannot begin. When the plant operators want to start the chain reaction they activate machinery that pulls the control rods away from the core. Once this is done a single free neutron is enough to set off the reaction. As the reaction continues, a moderator slows the neutrons down enough to ensure that they will continually split more uranium atoms. At the same time, the moderator acts as a coolant. It keep the overall temperature about 300 degrees Celsius. Since the temperature at spots inside the fuel rods may be as high as 1,100 degrees Celsius, enormous amounts of coolant are continually needed to keep the core temperature at the proper level. When the plant must be must be shut down the control rods are lowered all the way back into the core. That brings the chain reaction to a standstill. The core cools, and steam is no longer produced (23-24). In all nuclear reactions use uranium and produce some plutonium.
Since nuclear reactions produce a considerable amount of plutonium there are considerable hazards that come along with it. Nader and Abbotts, two men who have a great amount of experience in the nuclear industry, comment that:
Plutonium’s major dangers include the fact that it is weapons-grade material, that it is highly toxic, and it is extremely long-lasting: it will take 24,000 years for half of it to decay. In addition to the possibility that plutonium could contaminate the environment or the population in an accident, there is also the danger that a terrorist group could steal plutonium for the purposes of fashioning an illicit nuclear weapon. (63)
Plutonium-239 is a man-made reactor by-product which emits highly energetic alpha particles. Even though alpha particles can be stopped by a piece of paper that can be very dangerous to tissue if they are taken into the body by ingestion or inhalation. Expressing extreme concern over the issue of plutonium getting into the human body Nader and Abbotts write:
Experiments with dogs show that the inhalation of as little as three millionths of a gram of Pu-239 can cause lung cancer. John Gofman has reported that plutonium and other alpha-emitters, such as curium and americium [other products of a nuclear reaction], when in a form that cannot readily be dissolved by body fluids, ‘represent an inhalation hazard in a class some five orders of magnitude [100,000 times] more potent, weight for weight, than potent chemical carcinogens.’ The fact that plutonium has a very long half-life, 24,000 years, makes it one of the deadliest elements known and one of the most difficult to manage. (78)
The reason why plutonium is so dangerous when it gets into the lungs is because plutonium releases radiation to a small mass of the lung at a very short distance. This effect of radiation from plutonium giving a concentrated dose to one small area is much greater than if the same amount of radiation had been uniformly distributed throughout the lung. Another problem with plutonium is its toxicity. Plutonium is the most toxic of all elements. Fred H. Knelman, who was a senior executive on the nuclear control panel in Washington D.C., wrote, ?One pound of plutonium-239, distributed to the lungs of a large population, could cause between ten and fifteen million lung-cancer deaths? (32).
Plutonium is rapidly becoming more and more common throughout the world because it is being produced all the time in nuclear reactions. The Nuclear Control Institute, in Washington D.C., published a paper on the Internet describing the problem of plutonium production.
By the turn of the century, 1,400 metric tons of plutonium will have been produced in the spent fuel of nuclear power reactors, and some 300 tons of it will have been separated into weapons-usable form. Less than 18 pounds (8 kilograms) is needed to build a Nagasaki-type bomb. The amounts will continue to grow rapidly. By 2010, there will be 550 tons of separated plutonium in commerce, more than twice the amount now contained in the world’s nuclear arsenals. By that time, Japan will have acquired an amount of plutonium equivalent to the present U.S. military stockpile. (?The Problem?, 2)
The quote above has a few hidden statements behind it. First it predicts that soon other nations will have a greater nuclear arsenal than the U.S.A. Also the quote says that plutonium is growing to be an excess product from nuclear reactions and thus other countries who are not economically stable will have a greater tendency to want to sell some plutonium to power hungry politicians for money to help the economy of their own country.
The subject of plutonium directly relates to nuclear terrorism. The terrorists’ holy grail is to build a nuclear bomb. It is becoming increasingly easy to find the knowledge on how to build a nuclear bomb. The only thing that is holding terrorists back is getting their hands on some plutonium or weapons-grade uranium.
Christopher K. Mitchell, a student under professor J. Ruvalds, wrote a research report in physics 177N class that stated that when constructing a nuclear weapon, there would be two main issues for a terrorist. The first issue would be the knowledge required about building the bomb and making it work. Essentially, this knowledge is not a great problem. For instance, anyone can purchase a copy of “The Los Alamos Primer” for approximately twenty-three dollars. This book details the work of scientist who participated in the Manhattan Project tests in New Mexico. Inside the book, a terrorist could find the amount of uranium needed to create a successful nuclear explosion. In addition, the book details the different types of nuclear bombs and how to construct them. According to Carson Mark, a nuclear weapons specialist, a terrorist group would need some specialist, such as a nuclear physicist, a chemist, and an explosives engineer to build a nuclear weapon. In addition, some specialized equipment would be required. The second issue of building a nuclear weapon is the material needed to fuel the chemical reaction. Of the two issues, this one creates a much larger problem. Until recently, it was nearly impossible for a terrorist to even consider obtaining either bomb grade plutonium or uranium. In the past, these bomb grade fuels would have been nearly impossible to steal and the price to purchase such materials was far above the budget of any terrorist group. Many experts feel that it would cost at least five to ten million dollars to purchase enough plutonium to make a nuclear weapon. Others place the estimate as high as twenty or thirty million dollars (2). The problems of obtaining money and scientists are not big. The Soviet Union has left many of its top nuclear scientists without jobs and money. Many would be happy to get out of their crime ridden country to work for a terrorist group or another country associated with terrorism like Iran or Iraq. Money is not a problem for these two countries who hold some of the world’s biggest oil reserves. This paragraph represents only one type of terrorism that can be done with money and talent but what can other terrorist groups do who don’t have very much money?
One very vulnerable terrorist target is the nuclear powerplants. Scott D. Portzline, who has a Ph.D. is nuclear physics, writes that :
Considering the fact that a nuclear plant houses more than a thousand times the radiation as released in an atomic burst, the magnitude of a single attack could reach beyond 100,000 deaths and the immediate loss of tens of billions of dollars. The land and properties destroyed (your insurance won’t cover nuclear disasters) would remain useless for decades and would become a stark monument reminding the world of the terrorists’ ideology. With more than 100 reactors in the United States alone, if one is successfully destroyed, just threatening additional attacks could instill the sort of high-impact terror which is being sought by a new breed of terrorists. (1)
For years, what has caused concern for many observers and several federal oversight committees is a report on the potential for damage from truck bombs.
Unacceptable damage to vital reactor systems could occur from a relatively small charge at close setback distances, and from larger but still reasonable-sized charges at large setback distances, greater than the protected area for most plants. (?Nuclear Terrorism?, 2)
This represents the Nuclear Report Committee’s most feared result. At some plants, a large bomb detonated offsite can cause enough damage to lead to a deadly release of radiation or even a meltdown!
The release of radiation can come from different areas in the nuclear cycle. One of the biggest radiation threats is uranium mill tailings. ?After the uranium ore is separated, the tailings are left behind. Tailings contain radioactive thorium which remains dangerous for over 100,000 years? (?Nuclear Waist: The Big Picture?, 2). Thousands of tons of uranium mill tailings are being produced each year. Abbots and Nader comment that uranium mill tailings is a byproduct of the enrichment process. Less than one fifth of the amount of potential uranium is extracted in a given amount of rock or sand. (90) This leaves four fifths of the uranium that was inside the rock deep in the earth, on top of the ground in the form of sand. This sand can blow across large amounts of land. ?By 1986 2.7 billion cubic feet of tailings were blowing in the wind, damaging native crops and human life? (Nuclear Waist, the Big Picture 2). This is one of the biggest environmental hazard that we face today. Expressing their concern about uranium dust, Nader and Abbotts write :
Uranium dust represents a respiratory hazard to mine and mill workers, but most of the problems with uranium mining and milling are associated with uranium’s decay products. They present a much greater radiation hazard. Through a series of nuclear reactions, uranium undergoes radioactive decay to radium, which in turn decays ro radon gas. The radon gas in turn decays to isotopes which in turn can cause serious biological damage, particulary when inhaled. (82 – 84)
The serious results of having mill tailings open to the environment are just being felt now. Since the beginning of the nuclear age to the late 1960’s there has been no official record kept on where mill tailings have been stored. Many towns in the middle of the United States have been built on mill tailings. Some people unknowingly have used mill tailings as building materials. Corinne Browne and Robert Munroe, who are very well internationally known authors, state that :
In some places, such as Grand Junction, Colorado, people used the mill tailings as landfill and construction material. In Grand Junction, five thousand houses, a school, a church, a supermarket, and a hospital were built on tailings, thus creating situations where people live and work in buildings emitting radioactivity. (81)
In towns that have been built on mill tailings there is a great increase in health related costs because of an increase in cancers and radiation induced diseases. Corinne Browne and Robert Munroe go comment on the effects of living in an environment that has radiation.
In the early 1970s, a pediatrician in Grand Junction noticed an abnormally large number of children being born with cleft lips and cleft palates. A study showed that there was a far higher incidence of leukemia, hydroencephalitis, and subtle birth defects in the Grand Junction area than in surrounding counties. (81)
A person could then conclude that the nuclear industry is mostly to blame for the nation wide increase of cancers and deaths. Is the nuclear industry really benefitting the nation or is it just making the world into a radioactive dump which takes thousands of years to clean up?
One last major problem with nuclear energy that needs to be touched on is the storage of nuclear waste. Nuclear waste includes all contaminated parts that have had contact with any source of nuclear energy and all products of a nuclear reaction that was discussed at the beginning of the paper. There are several problems that relate to the storage of nuclear energy.
At a nuclear storage facility, there are security officers, technicians, scientists, and regular staff which make sure the facility is safe. In the paper, ?Uranium: Its Uses and Hazards?, it states the half-life of some radioactive isotopes. Uranium-238 which has a half-life of 4.46 billion years and that uranium-235 which has a half-life of 704 million years represent most of nuclear waste stored at nuclear waist facilities. (1) This means that people will have to be monitoring these facilities for about ten billion years. Fred H. Knelman is very concerned about the time and man power required to run these storage facilities. Knelman wrote :
There must always be intelligent people around to cope with eventualities we have not thought of….Reactor safety, waste disposal, and the transport of radioactive materials are complex matters about which little can be said with absolute certainty. Is mankind prepared to exert the eternal vigilance needed to ensure proper and safe operation of its nuclear system? (39)
The searching for proper storage facilities and places has always been one of the top priorities of the nuclear industry. The problem is that no one wants a nuclear waste facility in there back yard. Literally billions of dollars has been spent just on looking for places to store nuclear waste.
Nuclear energy has many short term benefits but many more short term and long term problems. If anyone of the lethal potential problems develop and get out of control than the world is in serious trouble. Can the world afford to be dancing with death? Just think if a nuclear plant exploded because of a terrorist attack how our lives would be changed forever. Are we unselfish enough live without a few comforts now so that our children can have a brighter future? A nuclear disaster is the worst thing that can happen to this planet because it threatens the whole future of the human race. Nuclear energy is not worth the risk. The problem of nuclear energy such as terrorism, plutonium production, uranium mill tailings, and waste storage problems make nuclear energy too risky for humans to even experiment with. Nuclear energy holds our future in a tight grip so we must do something about it.
Works CitNuclear Energy
You are watching the control panels and gages for rector two. Sitting comely you think about how easy your job is. It is a joke! All day you sit around and watch the gages for reactor number two just to make sure they maintain their settings. You don’t even need to look at the gages either because a computer automatically regulates them without you. Life is so good. Suddenly all the sirens go of and the gages and displays spin wildly in every direction. The ground shakes and you can hear the sound of a deep rumble. Unknown to you, the reactor’s cooling pumps have failed to cool the reactor’s core and in 3 seconds the temperature went from 280 degrees centigrade to 4,000 degrees centigrade. The water that was in the reactor is instantly turned to steam which creates tremendous amount of pressure in the reactor core. Above the reactor core there is a 5 foot thick lead plate and above that there is a meter thick floor composed of iron, barium, serpentine, concrete, and stone. The exploding steam fires the floor up like shrapnel. The metal plate goes through the four foot thick concrete roof like butter and reaches and altitude of sixty meters. You can hear ripping, rending, wrenching, screeching, scraping, tearing sounds of a vast machine breaking apart. L. Ray Silver, a leading author who covered the disaster at Chernobyl, said that within the core, steam reacts with zirconium to produce that first explosive in nature’s arsenal, hydrogen. Near-molten fuel fragments shatter nearly incandescent graphite, torching chunks of it, exploding the hydrogen. The explosion breaks every pipe in the building rocking it with such power that the building is split into sections (11-13). You look down at your body and notice that it feels hot and your hands look different. Unknown to you a tremendous amount of neutrons are hitting your cells and taking chucks out of your skin. Suddenly everything goes black.
The paragraph above describes the scene of what happened at Chernobyl nuclear plant a few years ago. From that time until the present many other smaller accidents have happened. From these accidents many people have died and millions have been indirectly affected. Nuclear energy has far to many negative problems than advantages. From the mining of uranium to disposal of nuclear waist there are problems of such magnitude that no scientist on this earth has an answer for. Nuclear energy has so many problems associated to it that it should be banned from the earth.
To understand the threat of nuclear energy we must first understand what happens in a nuclear reaction. Ann E. Weiss, who has written several books on the subject of nuclear energy, described what happens inside a nuclear power plant. In a nuclear reaction the nuclei of its atoms split, producing energy in the form of heat. The heat makes steam which powers a turbine. Fission takes place in a nuclear reactor. The fuel used is pellets of uranium. In a modern reactor, half-inch long pellets of uranium are packed into 12 or 14 foot tubes made of an alloy of the metal zirconium. About 50,000 zircalloy fuel rods make up the reaction core. To control a nuclear reaction control rods made of cadmium is used which absorbs neutrons. With the control rods in place in the core, a chain reaction cannot begin. When the plant operators want to start the chain reaction they activate machinery that pulls the control rods away from the core. Once this is done a single free neutron is enough to set off the reaction. As the reaction continues, a moderator slows the neutrons down enough to ensure that they will continually split more uranium atoms. At the same time, the moderator acts as a coolant. It keep the overall temperature about 300 degrees Celsius. Since the temperature at spots inside the fuel rods may be as high as 1,100 degrees Celsius, enormous amounts of coolant are continually needed to keep the core temperature at the proper level. When the plant must be must be shut down the control rods are lowered all the way back into the core. That brings the chain reaction to a standstill. The core cools, and steam is no longer produced (23-24). In all nuclear reactions use uranium and produce some plutonium.
Since nuclear reactions produce a considerable amount of plutonium there are considerable hazards that come along with it. Nader and Abbotts, two men who have a great amount of experience in the nuclear industry, comment that:
Plutonium’s major dangers include the fact that it is weapons-grade material, that it is highly toxic, and it is extremely long-lasting: it will take 24,000 years for half of it to decay. In addition to the possibility that plutonium could contaminate the environment or the population in an accident, there is also the danger that a terrorist group could steal plutonium for the purposes of fashioning an illicit nuclear weapon. (63)
Plutonium-239 is a man-made reactor by-product which emits highly energetic alpha particles. Even though alpha particles can be stopped by a piece of paper that can be very dangerous to tissue if they are taken into the body by ingestion or inhalation. Expressing extreme concern over the issue of plutonium getting into the human body Nader and Abbotts write:
Experiments with dogs show that the inhalation of as little as three millionths of a gram of Pu-239 can cause lung cancer. John Gofman has reported that plutonium and other alpha-emitters, such as curium and americium [other products of a nuclear reaction], when in a form that cannot readily be dissolved by body fluids, ‘represent an inhalation hazard in a class some five orders of magnitude [100,000 times] more potent, weight for weight, than potent chemical carcinogens.’ The fact that plutonium has a very long half-life, 24,000 years, makes it one of the deadliest elements known and one of the most difficult to manage. (78)
The reason why plutonium is so dangerous when it gets into the lungs is because plutonium releases radiation to a small mass of the lung at a very short distance. This effect of radiation from plutonium giving a concentrated dose to one small area is much greater than if the same amount of radiation had been uniformly distributed throughout the lung. Another problem with plutonium is its toxicity. Plutonium is the most toxic of all elements. Fred H. Knelman, who was a senior executive on the nuclear control panel in Washington D.C., wrote, ?One pound of plutonium-239, distributed to the lungs of a large population, could cause between ten and fifteen million lung-cancer deaths? (32).
Plutonium is rapidly becoming more and more common throughout the world because it is being produced all the time in nuclear reactions. The Nuclear Control Institute, in Washington D.C., published a paper on the Internet describing the problem of plutonium production.
By the turn of the century, 1,400 metric tons of plutonium will have been produced in the spent fuel of nuclear power reactors, and some 300 tons of it will have been separated into weapons-usable form. Less than 18 pounds (8 kilograms) is needed to build a Nagasaki-type bomb. The amounts will continue to grow rapidly. By 2010, there will be 550 tons of separated plutonium in commerce, more than twice the amount now contained in the world’s nuclear arsenals. By that time, Japan will have acquired an amount of plutonium equivalent to the present U.S. military stockpile. (?The Problem?, 2)
The quote above has a few hidden statements behind it. First it predicts that soon other nations will have a greater nuclear arsenal than the U.S.A. Also the quote says that plutonium is growing to be an excess product from nuclear reactions and thus other countries who are not economically stable will have a greater tendency to want to sell some plutonium to power hungry politicians for money to help the economy of their own country.
The subject of plutonium directly relates to nuclear terrorism. The terrorists’ holy grail is to build a nuclear bomb. It is becoming increasingly easy to find the knowledge on how to build a nuclear bomb. The only thing that is holding terrorists back is getting their hands on some plutonium or weapons-grade uranium.
Christopher K. Mitchell, a student under professor J. Ruvalds, wrote a research report in physics 177N class that stated that when constructing a nuclear weapon, there would be two main issues for a terrorist. The first issue would be the knowledge required about building the bomb and making it work. Essentially, this knowledge is not a great problem. For instance, anyone can purchase a copy of “The Los Alamos Primer” for approximately twenty-three dollars. This book details the work of scientist who participated in the Manhattan Project tests in New Mexico. Inside the book, a terrorist could find the amount of uranium needed to create a successful nuclear explosion. In addition, the book details the different types of nuclear bombs and how to construct them. According to Carson Mark, a nuclear weapons specialist, a terrorist group would need some specialist, such as a nuclear physicist, a chemist, and an explosives engineer to build a nuclear weapon. In addition, some specialized equipment would be required. The second issue of building a nuclear weapon is the material needed to fuel the chemical reaction. Of the two issues, this one creates a much larger problem. Until recently, it was nearly impossible for a terrorist to even consider obtaining either bomb grade plutonium or uranium. In the past, these bomb grade fuels would have been nearly impossible to steal and the price to purchase such materials was far above the budget of any terrorist group. Many experts feel that it would cost at least five to ten million dollars to purchase enough plutonium to make a nuclear weapon. Others place the estimate as high as twenty or thirty million dollars (2). The problems of obtaining money and scientists are not big. The Soviet Union has left many of its top nuclear scientists without jobs and money. Many would be happy to get out of their crime ridden country to work for a terrorist group or another country associated with terrorism like Iran or Iraq. Money is not a problem for these two countries who hold some of the world’s biggest oil reserves. This paragraph represents only one type of terrorism that can be done with money and talent but what can other terrorist groups do who don’t have very much money?
One very vulnerable terrorist target is the nuclear powerplants. Scott D. Portzline, who has a Ph.D. is nuclear physics, writes that :
Considering the fact that a nuclear plant houses more than a thousand times the radiation as released in an atomic burst, the magnitude of a single attack could reach beyond 100,000 deaths and the immediate loss of tens of billions of dollars. The land and properties destroyed (your insurance won’t cover nuclear disasters) would remain useless for decades and woed
Corinne Brown, and Robert Munroe. Time Bomb, Understanding the Treat of Nuclear Power. New York: William Morrow & Company, Inc, 1981
Knelman, Fred H. Nuclear Energy The Unforgiving Technology. Edmonton: Hurtig Publishers, 1976.
Mitchell, Christopher K. ?Nuclear Terrorism.? 14 Nov. 1996 Available : http://www.nucl.com/terror.html.
?Nuclear Waste: The Big Picture.? 10 Nov. 1996. Available: http://www.sfo.com/~rherried/waste.html.
Portzline, Scott D. ?Nuclear Terrorism.? 10 Nov. 1996. Available: http://www.nci.com/terrorism.html.
Ralph Nader, and John Abbotts. The Menace of Atomic Energy. New York: W.W. Norton & Company Inc, 1977.
Silver, L. Ray. Fallout From Chernobyl. Toronto: Deneau Publishers & Company LTD, 1987.
?The Problem.? 10 Nov. 1996. Available: http://www.wideopen.igc.org/nci/prob.htm.
?Uranium: Its Uses and Hazards.? 20 Nov. 1996. Available : http://www.ieer.org/ieer/fctsheet/uranium.html.
Weiss, Ann E. The Nuclear Question. New York: Harcourt Brace Jovanovich Publishers, 1981.
323