Nuclear Energy

What is nuclear energyStrictly speaking nuclear energy is the energy that is released by splitting the nucleus of an atom (nuclear fission) or joining two atom s to become an individual atom (nuclear fusion). Indeed, nuclear core comes.When one of these two physical reactions (the nuclear fission or nuclear fusion) atom s experience a slight loss of mass. This mass is lost becomes a large amount of heat energy as Albert Einstein discovered his famous equation E = mc 2.

However, often, when we talk about nuclear energy we are referring to electricity generation using nuclear reactions.

Keep in mind that although the production of electricity is the most common utility, nuclear energy can be applied in many other sectors, such as medical, environmental applications or war. You can see it in more detail in the section on applications of nuclear energy on this site.

nuclear energyn.1. The energy released by a nuclear reaction, especially by fission or fusion.2. Nuclear energy regarded as a source of power. Also called atomic energy.

History of nuclear energy

The Greek philosopher Democritus of Abdera was the first to give a definition of atom : the smallest constituent of matter. This was in the V century. C. Atom comes from the Greek and means "non-divisible". Although later appeared the concept of nuclear fission that is just splitting atom s gain energy.Later, in 1803, the British chemist John Dalton said in his book A New System of Chemical Philosophy that elements are formed from certain combinations of atom s and allatom s one element are identical. That is, all iron atom s are identical or uranium.

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From here the work of scientists focused on identifying all elements and clasificaros. The first to propose an arrangement was the English chemist Newlands. A proposal that other scientists as Lothar Meyer, Dimitri Mendeleev or Moseley undertook to study and modify until the current periodic table.In 1897, J. J. Thompson announced the discovery of a negatively charged particle which he called electron . It was also able to deduce the relationship between the charge of a particle (e) and mass (m). Electron s are negatively charged elements that are orbiting around a nucleus as if they were planets orbiting around the sun core and electron s form the atom as Rutherford discover later.The radioactivity discoveryIn 1896, the French physicist Antoine-Henri Becquerel found that certain substances, such as salts of uranium, producing penetrating radiation of unknown origin. This phenomenon became known as radioactivity .

The French scientist was working in his lab and carelessly left some uranium salts with photographic plates that appeared later evenings, despite being protected from sunlight. After investigating it realized that the deceased were the plates was uranium. With its discovery Becquerel became the "father of nuclear energy".

At the same time, the French couple formed by Pierre and Marie Curie in their research deduced the existence of another element higher activity than uranium, in honor of his homeland was called polonium. They were also the discoverers of a second element which they called radio.

These three elements, by their nature, take a great importance in the development of nuclear energy. Currently, the fuel of almost all nuclear power production use uranium as fuel.

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Subsequently, as a result of investigations by Rutherford and Soddy, would show that the uranium and other heavy elements emit three types of radiation: alpha, beta and gamma. The first two were made up of charged particles and found that alpha particles were helium nuclei of atom s and electron s were beta particles. Furthermore, it was found that gamma radiation were electromagnetic in nature.The Rutherford atom ic modelThe discovery of the nature of the radiation Rutherford allowed to study the structure of matter. With their experiments could deduce that the atom consisted of a central positive where all the mass was concentrated and the electron s revolving in orbits around the nucleus, like a little solar system. This meant that the atom was not solid as previously thought.

The discovery of Planck's constant and quantum theory

In 1900, the German physicist Max Planck formulated energy is emitted in small individual units called quanta. He discovered a universal constant known as Planck's constant, represented as h2.

Planck's law states that the energy of each quanto is equal to the frequency of electromagnetic radiation by said universal constant multiplied.

Planck's findings represented the birth of a new field of physics known as quantum mechanics and provided the basis for research in fields such as nuclear energy.

The theory of relativity of Albert Einstein

Albert Einstein is considered as the most well-regarded scientist in the history of the twentieth century. His famous equation E = mc 2 made turned out to be revolutionary for further study of nuclear physics, but in those days there was no means to prove experimentally. Thus energíaym E represents the mass, both interrelated through the speed of light c. This equation related másicas energy conversions, so it could be assumed that the two entities are different manifestations of the same thing.







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The Bohr atomThe Danish physicist Niels Bohr in 1913 developed a hypothesis, according to which the electron s were distributed in distinct layers, or quantum levels, some distance from the nucleus, forming the electron ic configuration of the various elements.For the Danish physicist, electron s revolved stationary orbits from which no radiation is not emitted, thus burying the old concept of the atom as indivisible, inert and simple , and appearing the hypothesis of a complex structure that would subsequently complicated energy manifestations.The discovery of the neutronThe discovery of the neutron was made by James Chadwick in 1932. Chadwick "measured" mass of the new particle deducing that was similar to the proton but electrically neutral charge. It was thus observed that the atom ic nucleus consisted of neutron s and proton s, the number of electron s equal to proton s.

With his discovery, Chadwick got a "shell" of ideal characteristics to cause nuclear reactions.

The discovery of artificial radioactivityThe marriage of Frederic Joliot and Irene Curie were the discoverers of artificial radioactivity .The conclusions reached by marriage Joliot-Curie, were based on the idea that the radioactivity of natural character hitherto, could be produced by man, building radioactive elements by bombardment with departed alpha molecule s of certain chemical elements.

The discovery of nuclear fission

In late 1938, on the eve of World War II, a team of German researchers at the Kaiser Wilhelm Institute in Berlin, built by Otto Hahn, Fritz Strassmann, Lisa Meitner and Otto Frisch, interpreted the phenomenon Nuclear fission through barium identification element as a result of cleavage uranium core.

Early studies on nuclear fission were conducted by Otto Hahn and Lise Meitner, based on the results obtained by the Joliot-Curie marriage, which by careful analysis, they found a intermediate atom ic number element in a sample of uranium bombarded with neutron s.Lise Meitner and Otto Frisch could deduce that by bombarding uranium with neutron s, uranium, he captured a neutróny cleaved into two fragments, emitting a large amount of energy. He had discovered nuclear fission.

The Manhattan Project - Early nuclear bomb

In 1939, at the beginning of World War II, Albert Einstein advised the president of the United States, F. D. Roosevelt, the development of the atom ic bomb. Einstein


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explained that thanks to the research conducted by Enrico Fermi and Leo Szilard, in the United States, and Frédéric Joliot and his wife Irene Joliot-Curie in France, was almost certainly very soon as possible trigger a nuclear chain reaction that would free up a large amount of energy. This procedure will also allow the construction of a new class of pumps.

Einstein also mentioned the shortage of uranium reserves in the United States and that this mineral mines were in the former Czechoslovakia and in the Belgian Congo. Proposed collaboration between scientists and industry to develop as soon as possible said pump.

Also reported that Germany had suspended the sale of uranium from the Czech mines, of which the Reich had taken over, which could mean that the Kaiser Wilhelm Institute scientists, might be pursuing nuclear fission experiments as well.

Albert Einstein The fear of nuclear war was a result of his deep knowledge of the progress of research in this field. He had to emigrate to the United States in 1933 from Germany, at the beginning of the persecution of the Jews.

From a letter from Albert Einstein:

"Recent work by E. Fermi and L. S. Szilard ... I suggest that the chemical element uranium ... can become a very important new energy source ... During the last four months the possibility of carrying out a nuclear chain reaction using a large amount of uranium has increased, this reaction would lead to large amounts of new elements energíaya similar to the radius ... This new phenomenon would lead tambiéna building bombs ...

Given this situation it seems advisable to maintain some contact between the government and the group of physicists working on chain reactions in America.

A possible way to achieve this might be that you could remove this charge to a trusted person.

His work in this area could be the following: ... ensure the supply of uranium to the United States ... accelerate the experimental ... raise funds ... "

Roosevelt hosted the Einstein letter without much enthusiasm, but created a commission to take charge of the issues mentioned by the scientist in the same.

Between 1940 and 1941 began to be measured in uranium-graphite systems, Glen Seaborg discovered in late 1940, an artificial element, plutonium-239, which could be used to manufacture the bomb tied back mica.

Making the bomb was entrusted to the army, in a war project would cost around 2,500 million. The program included two alternatives: the separation of uranium-235 from uranium-238, and plutonium-239 production in graphite reactors.

On December 2, 1942, a group of European nuclear physicists, who emigrated to the United States and led by the Italian physicist Enrico Fermi, put up the first nuclear chain reaction caused by man with the intention of applying for the first time nuclear energy. The employee nuclear reactor , known as Chicago Pile (CP-1) was a simple structure, and settled under the grandstand football stadium at the University of Chicago. Uranium fuel was used, such as that used in his experiments Fermi in Rome, and graphite moderator.Preparations for this experiment were carried out with great secrecy. The research objective was to obtain a chain reaction-controlled in principle to allow the study of their properties in view to the development of an atom ic bomb.Once extracted carefully control rods , began the chain reaction, thereby entering into the first reactor operation worldwide.In 1943 were lifted three cities full of research facilities: Oak Ridge (Tennessee) to separate uranium-235 from uranium-238, Hanford for the establishment of nuclear reactor s, and Los Alamos to build atom ic bomb. Robert Oppenheimer was named director of the Los Alamos laboratory, getting together about a thousand scientists who remain there until six months after the end of the race.

In the early morning of July 16, 1945, was conducted the first test of the plutonium bomb in the desert of Alamogordo (New Mexico), and proved to be a success.

The pump of uranium and plutonium were ready simultaneously. The first, called Little Boy, consisted of two masses of uranium-235 that were cast upon each other with conventional explosives.

The second, Fat Man, was a hollow sphere of plutonium collapsing around its center by the action of conventional explosives

On August 6, 1945, Little Boy was dropped on Hiroshima from the Enola Gay, and on August 9, Fat Man was dropped on Nagasaki.


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The Japanese cities of Hiroshima and Nagasaki thus became the first and so far the only targets of an atom ic bomb attack.The conditions for the construction of an atom ic bomb, which worked unsuccessfully during WWII some Soviet physicists, as Igor Vasilievich Kurchatov, were more stringent what is required to achieve successful operation of a nuclear reactor .

The energy released by detonation of this kind is split approximately 35% of thermal radiation, 50% of 15% presióny nuclear radiation.

This process where temperatures of up to 14 million degrees Celsius. The Hiroshima bomb released 23.2 million KWh.

The Nuclear Nonproliferation Treaty

After the end of World War II, America held the supremacy war because of its considerable potential atom ic. The complexity in the issues surrounding military and civilian nuclear energy, required the establishment of a joint legal for civilian applications in the country, and international regulation to all levels.





Although there were a number of international meetings, the United States were reluctant to lose their prominence, and he did know the President Truman to declare: "We must constitute ourselves as guardians of this new force, to prevent harmful use, and target it for the good of humanity

...

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In 1946, appeared at the United Nations on U.S. plan, which consisted of a gradual release of secrets, factories and nuclear bombs, giving it all to the body in return for control and international inspection.

This control was not well received by the former Soviet Union, whose representative, Andrei Gromyko, presented a counterproposal on banning the construction of atom ic weapons and requiring the phaseout , n of existing short term. After several years of negotiations, the first nuclear nonproliferation plan was a failure.

In June 1947, the Marshall Plan was born as an initiative of financial support within the U.S. policy of containment of Soviet control, which came under the Central European and Eastern behind what was called the "Iron Curtain". This plan was the trigger historic Cold War which followed a series of clashes between the two superpowers.

Years later, the United States built several plutonium reactors, and in 1953, became operational on ground prototype reactor Nautilus, the first nuclear submarine.These events emphasized the tense situation caused by the explosion of the Soviet H-bomb. The idea for this pump was making a big cylindrical container with the atom ic bomb at one end and the hydrogen fuel in the other. The explosion of the atom ic bomb radiation provide an amount sufficient pressure to compress and ignite hydrogen.After preliminary schemes 1951, the pump was ready in early 1952, so that in November this year, was tested by spraying the Elugelab Island in the Pacific Ocean. Proved potency 700 times that of the Hiroshima atom ic bomb.

On December 8, 1953, the United States went to the United Nations to denounce the balance of terror in the world's population lived, warning that if America was attacked with nuclear weapons, the answer Seri to destroy the aggressor immediately.





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In order to ease this situation, we organized a series of international technical on the peaceful uses of nuclear energy. This time, the talks between developed with significant atom ic potential were a complete success.Taking advantage of the new situation, U.S. President Eisenhower then exposed in the UN international cooperation program "Atom s for Peace". From this program, were released a series of scientific and technological knowledge that would allow the subsequent commercial exploitation of nuclear energy.

The speech, which in December 2003 turned 50, and was delivered at a time of cold war, proposing an agreement between the great powers to halt and reverse the manufacture of nuclear weapons and make known to all mankind the knowledge and material resources, especially the nuclear fuel for peaceful purposes.

Also, favored the creation of international organizations such as the International Atom ic Energy Agency (IAEA) in 1957, based in Vienna, and the Nuclear Energy Agency (NEA) integrated in the Organization for Cooperacióny Development (OECD) based in Paris.

However, countries like the UK and the former Soviet Union, had already begun their investigations to commercial deployment of nuclear power.

In 1956, the British opened the first nuclear power station at Calder Hall, giving rise to a series of reactors known as graphite-gas.

In 1963, General Electric was the company in charge of constructing a boiling water strictly commercial (Oyster Creek I), marking the beginning of the flood of applications to build nuclear power plants, factories fuel elements and researching small storage methods and reprocessing plants.

In 1967, the IAEA organized a group analysis of all technical issues that could contain a Nuclear Non-Proliferation Treaty, which would take effect in 1972.

The signatories agreed not to transfer nuclear weapons or assist in its manufacture, and pledged to establish the necessary safeguards for compliance.

Safeguards systems, worldwide, were as follows:

Antarctic Treaty: signed in Washington by 37 countries, which prohibited the use of this land for nuclear explosions and / or disposal of radioactive waste.


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Test Ban Treaty of Nuclear Weapons in the atmosphere and in outer space and underwater: signed in Moscow in 1963, acting as repositories United States, the former USSR and the UK. (7li7 )

Treaty "Principles Governing the Activities of States in the exploration of outer space" includes the Moon and other celestial bodies, and was signed in October 1967, acting as repositories United States, the former USSR and Britain, agreeing not put into Earth orbit or outer space objects with nuclear weapons.

Ban Treaty Nuclear Weapons in Latin America: Mexico signed in 1967. Nuclear Nonproliferation Treaty: in force since 1972 and extended in 1995 with the

United Kingdom, United States and the former USSR as depositories.

The development of nuclear energy was promoted at all times by the interest generated on the production of electricity using this energy source. Throughout the '60s and '70s, they began several nuclear programs in various countries.

Antoine-Henri Becquerel Antoine Henri Becquerel was born in Paris, it was the Nobel Prize in physics in 1903 was, by chance, discoverer of natural radioactivity and three types of radiation, β and γ.Nuclear submarine Nautilus The Nautilus is the world's first nuclear submarine. It was the first submarine to reach the North Pole in 1958. In 1980 it became a museum.

Nuclear fissionNuclear fission is one of two possible reactions that occur when working with nuclear energy.

In nuclear energy called nuclear fission dividing the nucleus of an atom . The core becomes different fragments with a mass equal to almost half the original mass plus two or three neutron s.



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The sum of the masses of the fragments is smaller than the original mass. This 'missing' mass (about 0.1 percent of the original mass) has been converted into energy according to Einstein's equation (E = mc 2 ). In this equation E is the energy obtained, ma the mass of which we speak and c is a constant, the speed of light: 299,792,458 m / s 2 . With this value of the constant c and you can see that by little we draw unit mass in a nuclear fission obtain large amounts of energy (see the definition of energy ).Nuclear fission can occur when a nucleus of a heavy atom captures a neutron , or can occur spontaneously.

Nuclear chain reactions

A chain reaction refers to a process in which the neutron s released during the fission produced additional fission in at least one nucleus. This nucleus turn produces neutron s, and the process repeats. The process can be controlled (nuclear power) or uncontrolled (nuclear weapons).

If each fission caused by a neutron plus two neutron s are released, then the number of fissions doubles in each generation. In this case, there are 1,024 10 generations fissions and 80 generations in approximately 6 x 10 23 fissions.

Energy released per fission

165 ~ MeV kinetic energy of the fission products ~ 7 MeV gamma rays 6 MeV kinetic energy of ~ 7 MeV neutron s from products Energíaa ~ fission ~ 6 MeV gamma ray fission products ~ 9 Anti-MeV neutrinos fission products

200 MeV








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1 MeV (million electron volts) = 1.609 x 10 -13 Joules

Critical Mass

Although nuclear fission occurring every two or three neutron s, neutron s are not all available for continuing the fission reaction. If conditions are such that the neutron s are lost at a rate faster than they are formed by the fission occurring in the chain reaction will not be self-sufficient.

Critical mass is the point where the chain reaction can become self-sustaining.

In an atom ic bomb, for example, the mass of fissile material is greater than the critical mass.

The amount of critical mass of fissile material depends on several factors, the shape of the material, its density composicióny, and the level of purity.

A sphere has the smallest possible surface area for a given mass, and therefore minimizes the leakage of neutron s. Bordering the fissile material with a suitable neutron "reflector", the loss ofneutron s can be reduced and the critical mass can be reduced.

Controlled nuclear fission

To keep track of sustained nuclear reaction, for every 2 or 3 neutron s released, only one should be allowed to give another uranium nucleus. If this ratio is less than one then the reaction is going to die, and if it is larger it will grow without control (an atom ic explosion). To control the amount of free neutron s in the reaction space must be present a neutron absorbing element. Most reactors are controlled by control rods made of neutron absorbing material strong, like boron or cadmium.In addition to the need to capture neutron s, neutron often have much kinetic (moving at high speed). These fast neutron s are reduced through the use of a moderator, such as heavy water and tap water. Some reactors use graphite as moderator, but this design has several problems. Once fast neutron s have slowed, are more likely to produce more nuclear fissions or absorbed by the control bar.Why use uranium and plutonium?




















The scientists knew that the most common isotope , uranium 238. There is a fairly high probability that an incident neutron is captured to form uranium 239 instead of causing a fission. However, the uranium 235 has a higher probability of fission.From natural uranium is only 0.7% uranium-235. This means it takes a lot of uranium to obtain the necessary amount of uranium 235. Moreover, uranium 235 can not be separated chemically from uranium 238, since the isotope s are chemically similar.Alternative methods had to be developed to separate the isotope s.

Plutonium 239 has a high probability of fission. However, plutonium-239 is not a natural element and should be.

These are the materials used in nuclear power plants.

Spontaneous nuclear fission

The rate of spontaneous nuclear fission is the probability per second that a given atom will spontaneously fisione - ie without any external intervention. Plutonium 239 has a very high rate of spontaneous fission compared to the spontaneous fission rate of uranium-235.

Operation of a nuclear power plantThe main use currently given nuclear energy is the electric power generation. Nuclear power plants are responsible for this process. Virtually all nuclear power plants in production using nuclear fission and nuclear fusion not currently feasible despite being under development.The operation of a nuclear plant is identical to that of a thermal power station operating with coal, oil or gas except in the way of providing heat to the water to convert to steam. For this nuclear reactor heat is produced by the fission reactions of the fuel atom s.

Globally, the 90% power reactors, i.e., reactors for the production of electrical energy are light water reactors (in water releases water pressed ebullition). So explain more fully the operation of this type of reactor.



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Operation of a nuclear

The basic principle of operation of a nuclear power plant is based on obtaining heat energy through nuclear fission core comustibleatom s. With this heat energy , which have a vapor of water, will convert into mechanical energy in a turbine, and finally convert mechanical energy into electrical energy by a generator.The nuclear reactor is responsible for rising and handling this atom ic fission generates a lot of heat. With this heat to water is heated into steam at high temperature pressure.The transformed into water vapor exits the containment building due to high pressing is subjected to reach the turbine and rotate. At this moment part of the heat energy of the steam is transformed into kinetic energy. This turbine is connected to an electric generator whereby the kinetic energy is transformed into electric energy.

On the other hand, the water steam that went out of the turbine, though it has lost calorific energy, continues being in gas state and very warmly. to re-use water contained in the mentioned water steam, it is necessary to refrigerate it before returning to introduce the water in the circuit. For it, once gone out the turbine, the steam goes to a bank or deposit of condensation where it cools by being in contact with pipelines of cold water. The water steam becomes liquid and by means of a bomb it is forwarded again to the nuclear reactor to return to repeat cycle.

That is why nuclear plants are always installed near an abundant supply of cold water (sea, river, lake) to take this water condensation in the tank. The column of white smoke can be seen emerging from some plants is that water vapor is raised when this heat exchange.









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Nuclear reactor A nuclear reactor is an installation capable of initiating, controlling and maintaining nuclear reactions. They can be thermal reactors or fast reactors.Types of reactors Nuclear reactors can be classified according to the fuel used, the speed of the neutrons, the moderator used and the material used as a refrigerant.

Nuclear reactorA nuclear reactor is an installation capable of initiating, controlling and maintaining nuclear reactions (fission usually) chain occurring in the core of the facility.

The composition of the nuclear reactor is formed by the fuel, coolant, control elements, structural materials and, in the event that it is a thermal nuclear reactor, the moderator.

Nuclear reactors can be classified as rapid thermal reactors and reactors.

Thermal reactors are those which function by delaying (moderating) the faster neutron s or increasing the proportion of fissile atom s. To slow the neutron s, called slow neutron s, a moderator is required which can be light water, heavy water or graphite.Fast reactors are not required to moderate the speed of electron s and using fast neutron s.

To build a nuclear reactor is necessary to have enough fuel, we call critical mass. Having enough critical mass means having enough fissile material in good condition to maintain a chain reaction.

The provision of neutron absorbers and control rods to control the chain reaction and stopping and starting of the nuclear reactor.









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In the reactor core occurs and manteiene the nuclear chain reaction in order to heat the water to be used for driving the turbine of the plant.

Components nuclear reactor core

A nuclear reactor consists of the following components:

Nuclear Fuel

Nuclear fuel is a material capable of fission enough to reach critical mass, that is, to maintain a nuclear chain reaction. Is positioned so that it can quickly remove the heat produced by this nuclear reaction chains.

In nuclear power plants using solid fuel. The nuclear fuels vary depending on the type of reactor used but generally uranium derivatives.

In general, a fuel element is constituted by a quadrangular arrangement of fuel rods, as seen in the image. While Russian nuclear reactor VVER pressurized water is constituted by a hexagonal arrangement.

The guide tubes are attached to the fuel support grids in this way is able to maintain the centers of the fuel rods and tubes guíaa the same distance.

The mechanical design of the different fuel elements is identical. Some contain bundles and control rods containing burnable poisons or other neutron sources.

To ensure the quality of the fuel elements, there are numerous inspections and testing of both raw materials and the final product.

Control rodsThe control rods beams provide a rapid means for controlling the nuclear reaction. Allow rapid changes reactor power and eventually stop in case of emergency. They are made of neutron absorbing material (boron carbide or alloys of silver, indium and cadmium, etc.) and typically have the same dimensions as the fuel elements. The reactivity of the core increases or decreases by raising or lowering control rod, that is,






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modifying the presence of neutron absorbing material contained in them in the nucleus.

For a reactor operated for a period of time must have an excess of reactivity which is maximal with fresh fuel and decreases over the life of the same until it is canceled, when the refill is made of fuel.

In normal operation, a nuclear reactor is the control rods fully or partially extracted from the nucleus, but the nuclear plant design is such that any fault in a security system or reactor control, always acts in the sense of security of introducing reactor completely all the control rods in the reactor core and carrying a safe stop in a few seconds.

Moderator

The resulting neutron fission reaction have high kinetic energy (high speed gain). The higher your speed is less likely to fisionen other atom s so that this speed should be reduced to encourage new chain reactions. This is achieved by elastic collisions of the neutron s with nuclei makes moderator element.

Among the most commonly used moderators are light water, heavy water and graphite.

Coolant

In order to use the heat energy given off by nuclear fission reactions using a refrigerant. The function of this heat refrigerant and transport aboserver. Coolant must be corrosion, with a large heat capacity and should not absorb neutron s.

The most common refrigerants are gases, such as carbon dioxide and helium, and liquid as the light water and heavy water. There are even some liquid organic compounds and metals such as sodium, also using for this function.

Reflector

In a nuclear chain reaction, a certain number of neutron tends to escape from the region in which it occurs. This neutron leakage can be minimized with the existence of a reflecting means to redirect them into the reaction region. In this manner serves to increase the efficiency of the reactor. The medium reflector surrounding the core must have a low capture cross section for not reducing the number of neutron s and to reflect as many of them.The choice of material depends on the type of reactor. If we have a thermal reactor, the reflector can be the moderator, but if we have a fast reactor reflector material must have a large atom ic mass to reflect neutron s in the nucleus with its original speed (inelastic scattering).

Shield

When the reactor is in operation, it generates large amounts of radiation. Protection is needed to isolate the installation workers caused by radiation from fission products.














Therefore, biological shielding is placed around the reactor to intercept these emissions.

The materials used to build this shield are concrete, water and lead.















Nuclear Fuel

















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Types of reactorsThe classification of types of nuclear reactor can be done in different ways depending on the criterion used. Among the most common criteria are:

According to the fuel used in nuclear reactor s found natural uranium and enriched uraniumnuclear reactor s. The natural uranium fuel contains the same proportion of uranium found in nature, while the enriched uranium fuel of this ratio is increased artificially. Other reactors use mixed oxides of uranium and plutonium.

Depending on the speed of the neutron s produced in the nuclear reaction of fission reactors differ fast reactors and thermal reactors.

According to the moderator can be used for heavy water reactors, light water or graphite.

Depending on the material used as refrigerant: common materials are gas (helium or carbon dioxide) or water (legera or heavy). Sometimes these materials, while also acting as a moderator. Can also use steam, molten salt, air, or liquid metal as coolant.

The differences between the different types of operating nuclear power plants are based on the type of reactor used for producing nuclear energy. The way electricity is generated from steam generated is similar in all nuclear plants.

Types of nuclear reactor s in operation:

Pressurized water reactor (PWR)

The pressurized water reactor nuclear reactor is the most used in the world. It has been developed mainly in the U.S., RF Germany, France and Japan.This nuclear reactor uses enriched uranium oxide in the form of fuel.

The moderator and coolant water is used.

The energy generated by the reactor core is conveyed by the circulating cooling water at high pressure to a heat exchanger where steam is generated to actuate the turbines.

Boiling Water Reactor (BWR)

The boiling water reactor, is also used frequently. Technology has been developed mainly in the United States, Sweden and the RF German.

In this reactor, water is used as coolant and moderator.

The fuel is enriched uranium oxide form.








Natural uranium reactor, gas and graphite (GCR)

This type of nuclear reactor used in the form of natural uranium metal fuel. The fuel tube is inserted into a magnesium alloy called Magnox.

The graphite moderator is used and the gas cooler is, carbon dioxide.

The technology of this type of nuclear reactor has been developed mainly in France and the UK.

Advanced Gas Reactor (AGR)

It was developed in the UK from nuclear reactor natural uranium-graphite-gas.

The main changes are that the nuclear fuel in the form of enriched uranium oxide, is added to stainless steel tubes and the vessel, prestressed concrete, contains the heat exchangers inside.

Gas cooled reactor at elevated temperature (HTGCR)

This nuclear reactor is a further evolution of gas-cooled nuclear reactor s. Developed in R.F. German, UK and U.S..

The differences with the previous are mainly three: helium is replaced by carbon dioxide as a refrigerant, is used instead of ceramic fuel and metal fuel gas temperatures are working with much more , s high.

Heavy Water Reactor (HWR)

This type of reactor has been developed mainly in Canada.

The fuel used is natural uranium in oxide form, is introduced in zirconium alloy tubing.

Its main feature is the use of heavy water as moderator and coolant.

In the most common design, fuel tubes are fed into a vessel containing the moderator. The coolant pressure is maintained to maintain its liquid state. Steam is produced in a heat exchanger through which water circulates light.

Fast Breeder Reactor (FBR)

There are various designs, with the Russian and French that are more advanced.

The main characteristic of fast reactor moderator is not used and therefore most of the fissions produced by fast neutron s.







The reactor core comprising a fissile zone, surrounded by a fertile area in which natural uranium is transformed into plutonium. You can also use the uranium 233-thorium cycle.

The liquid refrigerant is sodium, the vapor produced in the heat exchangers. His name "player" is because fertile area produces more fissile material than it consumes the reactor in operation, ie more than the new fuel is spent.

Advantages and disadvantages of nuclear energyDiscuss the advantages and disadvantages of nuclear energy is a difficult but necessary exercise to form an opinion on whether or not to go for this type of energy.

On most pages where nuclear energy is part of a subjective idea about the advantages and disadvantages of nuclear energy use. On this website we try to present as much information related to nuclear energy without taking sides to allow visitors to create their own conclusions.

However, in this section, we make a brief analysis on the main advantages and disadvantages that objectively the authors of this website we see on nuclear power.

Advantages of nuclear energy

A third of the energy produced in Europe comes from nuclear energy, this implies that emit 700 million tons of CO 2 and other contaminants generated from the burning of fossil fuels.

Currently consume more fossil fuels which are produced so that in the not too distant future these resources are exhausted. One of the great advantages of using nuclear energy is the ratio of the amount of fuel used and the energy obtained. This also translates into savings in transport, waste, etc.

As an alternative to fossil fuels as carbon oil, would avoid the problem of so-called global warming, qual, is believed to have an important influence that change global climate. Improve the quality of the air we breathe with all that this would imply the decline of disease and quality of life.

On this last point it should be noted that it really has a major influence on global warming are emissions from road transport and that generated by power generation fuels folic , fossils are relatively few. Still, one of the applications of nuclear energy (but little used) is to convert it into mechanical energy for transport.

Currently electricity generation is by nuclear fission reactions, but if nuclear fusion as practicable, provide the following advantages:

Would get a fuel source inexhaustible. In the reactor would avoid accidents by chain reactions that occur in the fissions. Waste generated are much less radioactive.

Disadvantages of nuclear energy

The main drawback and what makes it more dangerous is it safe to use the responsibility rests with the people. Irresponsible decisions can lead to accidents at nuclear power plants but, even worse, can be used for military purposes as demonstrated in the history of nuclear energy in the first time that nuclear energy was used after appropriate investigations was to attack Japan in World War II with two nuclear bombs.

A civil level, one of the main drawbacks is the generation of nuclear waste and the difficulty to manage them as they take many years to lose its radioactivity and dangerous.

Just a positive impact on climate change because the main source of emissions is road transport.

In the main countries of nuclear energy production to keep constant the number of operating reactors should be built 80 new reactors over the next ten years.

While it is economically profitable from the standpoint of fuel consumed on energy obtained is not whether analyzed costs construccióny launch of a nuclear plant given that , for example in Spain, the lifetime of nuclear power plants is 40 years.

Disadvantages increased security now with international terrorism. In addition to the proliferation of nuclear power obligaríaa plutonium recourse to fuel.

Although security systems are very advanced nuclear fission reactions generate some chain reactions that control the systems if fallasen provoke a radioactive explosion.

Moreover, nuclear fusion is unfeasible because of the difficulty of heating the gas to such high temperatures and to maintain a sufficient number of nuclei for a time sufficient to obtain a Energi ; to liberated than necessary to retain heat and is highly expensive gas.

Nuclear energy applicationsAlthough nuclear energy is mainly used for the production of electricity in nuclear power plants is not the only use of nuclear energy.

This type of energy appears in many other aspects of our life quotidiana and in science.

Nuclear power has other applications in various fields:


Industrial applications: for analysis and process control. Medical applications: in diagnosis and therapy of diseases. Applications in food-processing in the production of new species, conservation

treatments of food, pest insects and vaccine preparation. Environmental applications: the determination of significant amounts of pollutants into

the environment. Other applications such as dating, which uses the properties of carbon-14 fixation to

bone, wood or organic waste, determining their chronological age, and applications in geophysics and Geochemistry, taking advantage of the existence of naturally occurring radioactive materials for fixing the dates of the deposits of rocks, oil carbon.

Aspects of nuclear energy we develop further in the following sections.

Industrial applicationsThe use of nuclear power in modern industry in developed countries is very important for improving processes for measurement and automation, and quality control.Nuclear energy in medicineNuclear medicine is used in most hospitals radiochemical methods using laboratory research and diagnostic of a wide variety of diseases.Applications medioamientalesWithin the nuclear isotope techniques exist that allow work to improve the environment in problems like the greenhouse effect, water pollution, control of insects and other pests.

Nuclear energy in industryThe use of nuclear power in modern industry in developed countries is very important for improving processes for measurement and automation, and quality control.

The use of radiation is applied in a wide range of activities, either in quality control of industrial processes, raw materials (cement, power plants, oil refineries, etc..) Or quality control of products manufactured in series, as a prerequisite for the full automation of the production lines at high speed.

Irradiation with intense sources is considered as an operation to improve the quality of certain products (special plastics, sterilization products "disposable", etc..).

In addition, tracer experiments are performed to obtain an accurate and detailed status of industrial equipment to qualify for the prolongation of life.

Industrial sources usually produce no radioactive waste in the country that uses them, because once useless, the country's commercial signature provider to be removed when the replacement.

Use of radioisotope s as tracersThe fact that small amounts of radioactive substances can be measured quickly and with accuracy, makes radioisotope s used to further process or analyze the characteristics of said processes. These substances are known as tracers.

The tracers are used for the investigation of processes and can control the parameters of ventilation systems (flow, ventilation efficiency), for mixing, checking the degree of homogeneity, mixing time and mixer performance, maintenance processes for studying the transport of materials through pipes (leaks or escapes and flows), and systems for detection of wear and corrosion, determining the degree of wear of materials ( motors) and corrosion of processing equipment.

Quality Control scintigraphy

Gamma radiography constitutes a quality control technique for verifying essential welds in pipes and to detect cracks in aircraft components.

It is the most important application of iridium-192 sources, which alone come to cover 95% of non-destructive testing performed in the quality control of castings, welds metal building, etc. The rest of these controls is performed with cobalt-60 sources (for large thicknesses, up to tens of centimeters of steel) or thulium-170 (for small thicknesses of the order of millimeters).

Use of radiation in other industrial processes

Gamma radiation ionizes the material and creates free radicals, which are the intermediate species in many chemical reactions. Applied radiation (cobalt source-60) with the monomers used to manufacture the plastic is induced formation of large polymer chains, and if the irradiation is continued material, special plastics are high degree of crosslinking catenary, which considerably improves their properties such as thermal and electrical insulation. Thus, some polymer degradation induced by radiation, is a useful property for some types of packaging.

Production of wire and cables insulated with polyvinyl chloride gradient with gamma radiation, results in an increased resistance to thermal and chemical aggressions.

Another important product is linked polyethylene foam with radiation, used in thermal insulation, padding against impact, flotacióny vests and plastic wood composites solidified with gamma radiation.












It is the most important application of iridium-192 sources, which alone come to cover 95% of non-destructive testing performed in the quality control of castings, welds metal building, etc. The rest of these controls is performed with cobalt-60 sources (for large thicknesses, up to tens of centimeters of steel) or thulium-170 (for small thicknesses of the order of millimeters).
















It is the most important application of iridium-192 sources, which alone come to cover 95% of non-destructive testing performed in the quality control of castings, welds



metal building, etc. The rest of these controls is performed with cobalt-60 sources (for large thicknesses, up to tens of centimeters of steel) or thulium-170 (for small thicknesses of the order of millimeters).





Medical applications of nuclear energyThe applications of radionuclides related to human health emerged quickly after the discovery of X-rays At present, most of the hospitals and health centers have a Radiologíay Department of Nuclear Medicine Department, and radiochemical laboratory methods used for diagnosis and investigation of a variety diseases.

Nuclear Medicine

In nuclear medicine, a particular radionuclide is administered to the patient, in order to investigate a specific physiological phenomenon by means of a special detector, a gamma camera generally located outside the body. The injected radionuclide is deposited selectively in certain organs (thyroid, kidney, etc.) Can be seen from the gamma camera the size, shape and function of these organs. Most of these procedures are diagnostic, although some radionuclides are administered for therapeutic purposes. Radionuclides useful in nuclear medicine are as follows:

Diagnosis "in vivo" gamma emitting short half-life (metastable technetium-99, indium-111, iodine-131, xenon-133 and thallium-201) and positron emitting ultrashort half-life (carbon -11, oxygen-15. fluorine-18 and rubidium-82).

Diagnosis "in vitro": gamma emitters (Iodine-125, and cobalt-51 chromium-57) and beta emitters (tritium and sodium-24).

Therapy: beta emitters (iodine-131, yttrium-90 and estrocio-90).

Nuclear Medicine "in vivo": Using radiopharmaceuticals

Radiopharmaceuticals are substances that can be administered to the living body for diagnostic or therapeutic investigating organ function. Currently used for diagnostic radiopharmaceuticals of 100 to 300.

The isotope s used have a short half-life of minutes, hours or days and are prepared in radiopharmacy laboratories ensuring their properties and purity.Usually administered as part of simple molecule s or more complex molecule s bound to be distributed in organs you wish to explore.Positron emitting radionuclides are used in the technique known as positron emission tomography (PET). The positrons emitted by these radionuclides are annihilated with atom ic electron s, resulting in two gamma rays which propagate in opposite directions and are detected with a gamma camera having detectors located on both sides of the patient. This method is used to assess, among others, the operation of the Heart and Brain.The quality of the images obtained with this equipment is superior to conventional equipment, but now, because of its high cost and high technology, as to produce these isotope s must have a ciclotró No, there are only equipment sold in countries with high level of medical technology. Spain has several teams of these features in their units oncology, neurology cardiologíay.

Another important technique is the scan, which detects gamma radiation emitted by the radiopharmaceutical attached to organ to be studied, on a computer called a gamma camera, the detector is placed on the body, receiving photons from the radiopharmaceutical.

These signals are converted into electrical pulses that are amplified and processed by a computer, enabling the spatial representation on a display or x-ray, on paper or displaying successive images of the body for further study.

Currently, gamma cameras allow to obtain three-dimensional organ cuts, improving the quality of the studies and the diagnostic sensitivity.

Thyroid scintigraphy consists in obtaining the image of the thyroid gland, the patient administering an isotope such as iodine-131 and technetium-99, which is fixed in the cells of this gland. It is used to diagnose the presence of alterations in shape, volume or thyroid function, as goiters, hyperthyroidism, thyroid cancers, etc.

Adrenal scintigraphy provides information on the form and function of the adrenal glands, which can cause malfunctions diseases like Addison's disease, Cushing's syndrome, etc. .

With different isotope s and administration forms can be studied cardiovascular disease (angina pectoris and myocardial infarction), digestive (cysts or tumors from digestive or intestinal absorption) and lung (tumorous involvement of the lungs).

The bone scan to diagnose infections and tumors in bone, by detecting the accumulation of the radiopharmaceutical injected into the patient in the affected areas.









Studies of the central nervous system (CNS) scans these techniques are useful for evaluating the various types of dementias, epilepsy and vascular diseases or tumors, which can not be detected by nuclear magnetic resonance or by Computed tomography (CT).

Nuclear Medicine "in vitro"

The analytical technique called radioimmunoassay, to detect and quantify existing substances in blood and urine, and are difficult to detect by conventional techniques. It is performed through the combination of the antibody-antigen binding with isotope labeled, generally iodine-125, one of these two components, generally the antigen.To perform this type of analysis, the patient does not come into contact with radioactivity , since the analysis is performed on the blood taken from the patient.

It is a technique of great sensitivity, specificity and accuracy, which is applied to various fields:

Endocrinology: determinations of thyroid hormones, adrenal, gonadal and pancreatic stimulus to test dynamic and braking.

Hematology: determinations of vitamin B12, folic acid, etc.. Oncology: determinations of tumor markers for the diagnosis and monitoring of

tumors. Virology determinations of markers of hepatitis B and C. Farmacologíay toxicology: determination of drugs in blood, detecting possible

sensitivities of organisms to allergies.

therapeutic nuclear medicine

The specialty of nuclear medicine employing ionizing radiation for the treatment of malignant tumors known as radiotherapy.

When using unsealed radioactive sources discussing metabolic radiotherapy, which involves injecting or do eat a relatively large dose of a radioactive substance in liquid form, to accumulate in the body you want treat, where it acts by means of radiation emitted on fabrics in contact therewith, producing the desired effect of destroying tumor cells.

This type of therapy is used to treat hyperthyroidism, thyroid cancer, bone metastases from prostate and breast tumors and can be used alone or in combination with other therapeutics as cirugíao chemotherapy.

In the case of thyroid cancer iodine-131 is used, that being gamma emitter, patient Entering special units radioproteccióny units have specialized medical care. Once the patient has been discharged, is performed periodically dosimetric control to monitor and verify that, by low doses of gamma radiation, the patient can live with his family and rest of the population.



Applications of radiation therapy may include the following:

Teletherapy: a technique in which the radioactive source is not in direct contact with the tumor being treated. Among gamma emitters used, stresses the encapsulated source of cobalt-60, contained in the pump called cobalt, which prevents the exit of the radiation except for one orifice which provides a directed radiation. Produces high energy radiation (1.2 MeV) capable of irradiating large tumors located deep. Teletherapy also be administered with electron beam emitting sources and neutron .

Brachytherapy is a technique in which the radioactive source is in direct contact with the tumor. When radioactive material plates are placed over the tumor area is called brachytherapy surface, if this source is introduced into the patient temporarily in natural cavities, intracavitary brachytherapy spoken and often used encapsulated sources of cesium-137, and if placed radioactive sources in certain tissues is known as interstitial brachytherapy. One of the problems of this therapy, also known as Curietherapy is possible unnecessary exposure of the patient and medical personnel to radiation sources, therefore, the source is placed in the positions n correct at the patient and medical personnel employ remote control commands to prepare, transport and handle radioactive sources.

Radiology

Diagnostic techniques consist of body imaging using X-ray equipment, which cross the exploratory field to be studied. At present, there are many developments in this field emphasizing ultrasound techniques, which use ultrasound or magnetic resonance imaging uses no ionizing radiation.

Thanks to radiology X, may be studies of skeleton, thorax, abdomen, nervous system, gastrointestinal tract, urinary tract, heart, etc. The radiographic image is obtained when crossing the X-ray beam to explore the area and X-rays being absorbed differently depending on the tissue, obtaining an emergent beam having intensity variations visible on a screen, disclosed that results in a radiograph.



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Diagnostic Another important technique is computed tomography (CT), which is to obtain a three-dimensional computer projection from overlapping cuts organ to study, produced by a thin collimated X-ray beam that revolve around it.

Mammography is the imaging technique used for the exploration of the breasts, allowing to study the soft tissues with high contrast and diagnosis of benign and malignant breast lesions, even of small dimensions.

The dental radiology, uses special equipment like pantomografías intraoral films (panoramic radiographs of the mouth) that improve the diagnosis of dentist.

Nuclear Energy and the EnvironmentPopulritat Although nuclear energy is very low there are applications of nuclear energy for works for the environment.

What is the relationship between nuclear energy and the environment?

To reduce pollution in the environment, we need to know where and how much to find these pollutants, the causes of contaminacióny the right solution to prevent it from spreading.

The main source of pollution is found in human activities contributing largely to the increase in pollutants, growth poblacióny industrial technological developments.

At present, the biggest environmental problem is global warming, the greenhouse effect accordingly.

The contamination of surface water and groundwater problem are also environmentally important.

The nuclear energy implementation allows isotopic techniques, it is a procedure that uses the interaction of ionizing radiation with matter useful to an end, which is most effective than other conventional procedure.

This can be useful purpose:

The investigation of the mechanism of an industrial process Measuring the performance of a gland The sterilization of a product or determination of the degree of contamination of surface and groundwater.

Application of nuclear energy to the problem of greenhouse

Global warming phenomenon is provably the most harmful to the environment. This is due to the release of gases during the combustion of organic materials Carbony like oil, wood and garbage.

Nuclear power allows the use of isotopic analyzes that calculate the carbon dioxide emissions in an industrial area. Nuclear methods such as electron beam irradiation, are very useful for removing gaseous pollutants, including harmful gases like sulfur dioxide or nitrogen oxide emitted in Carbony fuel power plants.

An innovative and simple method to calculate the carbon dioxide emissions, is the observation of the plants growing in an industrial area, which capture radioactive carbon-14 from cosmic radiation (radia , n solar, etc.) as carbon dioxide, and also incorporate emitted by industries, by determining what proportion of radioactive and non-radioactive carbon can determine the total emission carbon dioxide in the area.

Application of nuclear energy to the problem of pollution of surface and groundwater

Isotope techniques can help assess the vulnerability of groundwater to pollution from the surface, and allow precise surface pollution sources (natural, agricultural, domestic and industrial) discovering an incipient pollution, serving as an early warning chemical or biological indicators show no signs of concern.Building capacity "sterilizing" radiation is used to eliminate pathogens from wastewater. Internationally, it has promoted the use of electron beam accelerators for advanced large-scale treatment of contaminated water, mainly directed to the treatment of wastewater and drinking water.

Application of nuclear energy to the problem of soil contamination

The problem of soil pollution became important after the studies of pollution of water and air, as it was found to affect the food chain. The most commonly used agricultural




chemicals pollutants entering the soil through nitrogen fertil izers and pesticides, which should be tested carefully before use to ensure their decomposition products not create risks for man and the environment.

The application of isotope techniques to determine the breakdown of these products and their final destination. The nuclear method is most suitable for contaminacióny accurately assess the exact source that caused the pollution, and for determining the filtration pipes containing oil or spillage of chemicals transported.

Application of nuclear energy to eradicate insect pests

Sometimes insects are a threat to the health of animals and humans and may even destroy valuable food crops.

Traditionally used insecticides, but their chemical composition were a potential risk of environmental pollution and toxic waste existence in food. Moreover, higher resistance to developed insects them having to use higher amounts.

Currently, they are developing new methods of insect control, they do not pose a risk to the environment. You can highlight the following:

Sterile Insect Technique (SIT) is the production of large amounts of plant-breeding insects, which are sterilized with gamma radiation from radioactive cobalt sources 60 and cesium-137, to be released in areas affected by the plague. When sterile insects mate with wild insects produce no offspring, thus reducing the population of pest insects. SIT is species specific, so you can not have an adverse impact on other species of both insects and other animals or plants. This technique is useful not only to eradicate the pests, but also to control agricultural pest free areas. Among the applications of SIT are eradicating pests New World screwworm, the Mediterranean fruit fly, the tsetse fly, transmitter of diseases in man and animals, especially in Africa and the mosquito that transmits malaria.

Genetic manipulation for the selection of male insects: bugs releasing males only allows flies eradicate pests TIE reinforcing technique. To genetically manipulate flies, so that only males are released by ionizing radiation chromosomes are altered. If there are only male insects, plants will sterile insect rearing increased performance.

inherited sterility: this technique is mainly used to eradicate pests moths. It has been shown that with low doses irradiating a moth population, their descendants are sterile, and this may control insect family. For this technique, the sources used are stations gamma (cobalt-60).

nuclear energy application to hydrology

The water scarcity and degradation are of concern worldwide. Failure to optimize water resources could result in reduced economic growth and emerge certain risks to human health and the environment.

Isotope hydrology can understand the behavior of water and helps set the foundation for a rational use of this resource. The main uses of radio isotope s are dating to determine the age and transit time of the waters, and as tracers to determine the




source, the flow rate, the sources contaminacióny degradation processes. Among employees include radioactive isotope s tritium, carbon-14, oxygen-18 and chlorine-36.The application of isotope techniques in hydrology provides information on groundwater in regard to their origin, age, distribution, water quality and possible interconnections with groundwater, and surface water, in regard to the transport of suspended sediment in the bottom, possible seepage of dams and river discharges, the rate sedimentacióny filtracióna the underground conduits. Other notable applications of isotope techniques are as follows:

Nuclear Desalination: nuclear techniques are used for desalination of sea water to produce fresh water without disturbing the environment, as in plants that use steam and electricity from fuels folic siles, and it also supports the high energy consumption that these processes entail.

New isotope s useful in hydrology: Boron isotope s are used to treat groundwater contamination, chloride isotope s to determine the source of salinity, water age and size of a reservoir, and krypton-85 and helium-3 to improve methods of measurement of isotope s to help define the age of the water.

Nuclear powerNuclear plants are facilities where nuclear fission reactions cause to generate electricity.

Here below you can see that there are nuclear power plants in the following countries. You will find a brief description of each plant and its location.

As you can see, there are still many countries that are not available but this is a section of the website in development.

Nuclear power plants in Abu Dhabi Nuclear power plants in Argentina Nuclear power plants in Armenia Nuclear power plants in Belgium Nuclear power plants in Bulgaria Nuclear power plants in Canada Nuclear power plants in China, mainland Nuclear power plants in Czech Republic Nuclear power plants in Finland Nuclear power plants in France Nuclear power plants in Germany Nuclear power plants in Hungary Nuclear power plants in India Nuclear power plants in Iran Nuclear power plants in Italy Nuclear power plants in Japan Nuclear power plants in Kazakhstan Nuclear power plants in Korea RO (South)








Nuclear power plants in Lithuania Nuclear power plants in Mexico Nuclear power plants in Netherlands Nuclear power plants in Pakistan Nuclear power plants in Romania Nuclear power plants in Russian Federation Nuclear power plants in Slovak Republic Nuclear power plants in Slovenia Nuclear power plants in South Africa Nuclear power plants in Spain Nuclear power plants in Sweden Nuclear power plants in Switzerland Nuclear power plants in Taiwan Nuclear power plants in Ukraine Nuclear power plants in United Kingdom Nuclear power plants in United States

Status of nuclear power in the worldThe nuclear situation is different in different countries. Energy policy, needs and technical and financial resources of each country are different.

Spain for example, began its nuclear project but later strongly approved the declaration of the nuclear moratorium that blocked 5 of the 7 nuclear projects in progress.

In contrast, in Chile is betting on the study and use of nuclear energy as a source of development.

So it pays to do a review of countries

Nuclear Power in Spain Nuclear Power in Argentina Nuclear Power in Chile Nuclear Power in France

Nuclear energy in SpainStatus of nuclear energy in Spain. History of nuclear energy in Spain and their evolution over time.Nuclear Energy in MexicoThe development of nuclear power in Mexico. The construction of the first nuclear plants. Mexico's nuclear capability. Waste management.Nuclear energy in ArgentinaArgentina is one of the countries that have chosen nuclear energy. Currently there are three reactors for power production.Nuclear energy in ChileStatus of nuclear power in Chile. History of Nuclear Energy in Chile and its evolution over time.

Nuclear energy in FranceFrance ranks first worldwide in nuclear energy production by population density. Currently operating 19 nuclear power plants with 58 reactors. French nuclear reactors operated by the dual-channel system.

Nuclear wasteOne of the main problems of the use of nuclear energy is the management of nuclear waste as they are very dangerous and difficult to remove.

What is done with the nuclear waste?

Nuclear waste is one of the main problems of nuclear energy. If this waste is not properly treated, are highly hazardous to the environment poblacióny.

Radioactive waste can be classified according to their physical and chemical characteristics and activity.

Classificandolos for activity are:

high-level nuclear waste, composed of fuel elements won. intermediate level nuclear wastes are radionuclides produced in nuclear fission

process. low level nuclear waste, it is basically the tools, clothes and other material used for

matenenimiento of a nuclear power plant.

The National Radioactive Waste (ENRESA) is the company in charge in Spain of the nuclear waste management (come from nuclear or other radioactive facilities such as hospitals and research centers related to nuclear energy). The management of such nuclear waste is defined in the Waste Plan approved by Parliament.

The protocols for the treatment of nuclear waste depends on its level of radioactivity :

Nuclear waste medium and low activity

The intermediate level nuclear waste generated by radionuclides released in the fission process (which is currently used in nuclear power plants) in small amounts, well below those considered dangerous to the safety and the protection of persons.

With a separate treatment containing radioactive elements in these by-products and residues deposited solidifying steel drums with tar, resin or cement.


The low level nuclear waste radioactive (clothes, tools, etc.) are crushed and mixed with concrete to form a solid block. As in the previous case they are also introduced in steel drums.

This content is distributed on the website Enresa under conditions of the Creative Commons Attribution - No Derivative Works (BY-ND) 3.0

In Spain, the drums are moved to the Storage Center The Cabril (Córdoba), which manages ENRESA. Besides all nuclear waste deposited all Spanish plants, also deposited nuclear waste generated by the medicine, research, industry and other fields that also work with energy nuclear.

All nuclear waste storage, today, are strictly monitored and controlled.

high-level nuclear waste

Once spent fuel in a nuclear power plant, is removed from the reactor to be temporarily stored in a water pool walls constructed of stainless steel hormigóny within the plant to create a barrier to radiation and prevent leakage.

If it is true that these pools can be extended by an operation called "reracking" recent General Waste Plans provide for the construction of temporary dry storage inside the nuclear plant itself. This would be an addition to the pools in the intermediate step to define a permanent location.

Research on final storage takes place in many countries, some of which, such as Finland and the U.S., have taken significant steps to construccióny commissioning.

One of the solutions which are accepted among experts is Deep Geological Disposal (AGP), usually in mines excavated in stable geological formations.

Currently ENRESA works to locate, build and manage a Centralized Temporary Storage to store as a temporary and safe, high-level nuclear waste currently stored at the Spanish plants. This storage will buy time to find a suitable location for the AGP allowing continuity of nuclear facilities and the safe storage of high level waste.

European Nuclear Waste Classification

Since not all countries use the same classification, the European Commission has recommended unify criteria, for which he proposes the following classification, in force since January 1, 2002 :

transition nuclear waste: waste, mainly from medical origin, which disintegrate during the period of temporary storage and can then run as non-radioactive waste, provided that derating values.

Nuclear waste, low and intermediate level: the radionuclide concentration is such that thermal power generation during its disposal is sufficiently low. Turn are classified into short-lived waste containing radionuclides whose half-life is less than or equal to 30 years, with a limited concentration of long-lived alpha radionuclides-and long-lived waste radionuclide-and long-lived alpha emitters whose concentration exceeds the limits for short-lived waste.

high-level nuclear waste: waste with a concentration of such radionuclides to be taken into account thermal generation during its storage and disposal. This type of waste is mainly the treatment and conditioning of spent fuel.

Transport Management and Storage space The term waste management as a set of activities that lead to reuse their disappearance or neutralization and escape to right places, ensuring long-term security.

Renewable energy

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The classification of renewable natural resources depends on taking advantage.

Solar Energy

Aprovechameiento distinguish two forms of solar energy :

Solar Power Solar Photovoltaic

The use of thermal solar energy is to use the heat energy obtained from the sun's rays to heat a fluid, depending on its temperature, is used to produce hot water or even steam.The use of Photovoltaic Solar Energy is through the direct conversion of solar energy into electricity through the photovoltaic effect called. This transformation is accomplished by "solar cells" which are made of semiconductor materials (eg, silicon) that generate electricity when incident solar radiation over them.

Wind Energy

Wind energy systems use the kinetic energy contained in the wind to produce electricity using wind turbines called. There are two types of wind turbines:

Isolated, to generate electricity in remote locations to consumption. It is very common that these premises are combined with photovoltaic panels.

Wind farms, consisting of a set of wind turbines, to sell the electricity generated to the grid.

Current technological development and a greater knowledge of wind conditions in different areas, is allowing the installation of wind farms connected to the grid in many regions around the world .

Energy Minihidraulic

The use of the potential energy of water from a break to produce electricity is what is known as hydropower. The water turbine which drives a movement of rotation is transferred via a shaft to a generator. It is considered that this type of renewable energy when the power is less than 10 MW (small hydro power).

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There are basically two types of hydropower:

Central flowing water: those that capture a portion of the flow for Rioy lead him to headquarters to be turbinado and generate electricity. Then this flow is returned to the river.

walk Central prey: Those downstream of reservoirs for hydroelectric purposes or other purposes such as water supply or irrigation populations. They have the advantage of storing energy (water) and its use with the times when it is most needed.

Biomass Energy

Biomass is an energy source based on the use of organic materials of plant or animal origin, including the products and by-products resulting from the processing. Under the heading of biomass energy materials are collected in many different classes: forest residues, agricultural residues and woody crops, various industrial process waste, energy crops, organic materials contained in municipal solid waste, biogas from livestock waste or biodegradable waste from industrial plants of urban waste water treatment or landfill, etc. They can also be included under the heading of biomass, biofuels, which are mainly used in the transportation.

The biomass applications can be categorized into two groups:

domestic and industrial applications that run on direct combustion of biomass. Applications related to the development of new resources and new processing

techniques, such as gasificacióny pyrolysis of biomass.

tidal power and wave

The seas and oceans are immense solar collectors which can extract energy from various sources (wave, tidal and thermal gradients).

The energy released by the seawater in its upward and downward movements of the tides (ebb and flow) is used in tidal power stations, by passing the water through turbines.

The wave energy is produced by wind and very irregular. This has led to many types of machines for use.

Finally, ocean thermal energy conversion is a method of converting into useful energy the temperature difference between the water and the water surface is to 100 m depth. Is sufficient to use a gap of 20 ° C. The advantages of this energy source that is associated with a thermal constant and benign from an environmental perspective.

Geothermal Energy

Geothermal energy is the manifestation of the thermal energy stored in rocks or water which is high temperature inside the earth.

For the use in areas with special temperature conditions, for example volcanic areas, is circulated in a fluid which transports them to the surface in the form of heat energy accumulated heat in the hot zones.

The energy generated in function of its temperature (high, medium or low) is utilized either to generate electricity or for water heating and heating.

Geothermal energy has the main advantage that their environmental impact is minimal and has yields that allow it to compete with oil. But its main disadvantages are that they require large investments and geothermal fields are relatively scarce and often are located in unfavorable areas.

DefinitionsAtom

Atom is defined as the smallest particle into which an element can be divided without losing its chemical properties.

Atomic nucleusThe atomic nucleus is the central part of the atom small, positively charged and which concentrates most of the mass of the atom.

Atomic numberNumber of elementary positive charges, or protons, carried by the nuclei of all the isotopes of a given element.

Control rodsIn the nuclear control rods are cylindrical tubes that absorb neutrons is possible to control the reactor power.

Electric powerPower defined as the form of energy that results from the existence of a potential difference between two points. When these two points are the contacts as a conductor obtain an electric current.

ElectronAn electron is a negatively charged elementary particle stable which is one of the fundamental components of the atom. It is part of the group of leptons.

EnergyEnergy is the ability of a system to produce physical work. Or what, when an work, decreases by an amount equal to the work done.

Heat energyHeat energy is the manifestation of the energy as heat. It can be transmitted by radiation, conduction and convection.

Isotope



Each of the atoms whose nuclei have the same number of protons but a different number of neutrons.

MoleculeDefining molecule. A molecule is an aggregate of atoms chemically bonded together, which is electrically neutral.

NeutronA neutron is a subatomic particle contained in the atomic nucleus. Has no net electrical charge, unlike the proton positive electric charge. The number of neutrons in an atomic nucleus determines the isotope of that element.

Nuclear power stationA nuclear power plant is a thermal power station in which the heat source comes from one or more nuclear reactors.

ProtonA proton is a positively charged particle is inside the atomic nucleus.

RadioactivityThe definition of radioactivity is the spontaneous emission of particles (alpha, beta, neutron) or radiation (gamma capture K), or both at once, from the decay of certain nuclides that are, due to an arrangement their internal structure.

GUYANA IMPORT HAZARD

Customs and other first responding agencies in the Caribbean apparently are slowly waking up to the fact that cars, other vehicles and spare parts from an area in Japan where a radioactive nuclear plant failed after a massive earthquake and tsunami more than three years ago, are being sneaked into various Caribbean countries, unbeknownst to people who should be alert to that possibility.

But thanks to vigilant customs officials in Jamaica and the alarm bells they rang last month after detecting unusually high levels of radiation on a 40-foot container transiting the island to Guyana, regional authorities say they will step up the levels of vigilance to ensure only sanitized vehicles make it onto roads in the Caribbean.

Until the discovery at one of Jamaica’s main world class transiting piers last month, vehicle and spare parts dealers like Guyanese Wilfred Bransford said that while they were aware that hundreds of vehicles were covered with contaminated water after the Fukushima Nuclear plant broke down in the aftermath of the disaster, they were unaware that polluted vehicles and parts had reached the region.

Bransford says that he will now insist that certificates of inspection be issued and he insists that the two dealers with whom he has been associating for more than a decade “would not risk their reputations” to send radioactive and contaminated vehicles to him in Guyana.

Still, the Guyanese health ministry surprisingly said that they had only become aware of the Jamaican interception last weekend and would now move to take action to step up monitoring. Head of Customs and Revenue Kurshid Sattaur said the matter is not that serious as he accused local media of over blowing and sensationalizing the issue unnecessarily.

But the region should have been on a higher level of alert for the past two years.

In late 2012, Jamaican authorities also discovered a passenger mini bus for a buyer on the island with similarly high levels of radioactive material on a city pier and impounded it as well but that very incident has only now come to light after the transiting Guyana container made news headlines. Both the container and mini bus are to be sent back to Japan.

Guyana has no Geiger Counter to measure or test imports from Japan or any other affected country for acceptable radiation levels. In fact, many of those questioned in recent days said they had never ever heard of such a piece of high tech testing equipment. Health Minister Bheri Ramsarran said only that “we will look into this serious matter,” while the head of the revenue and customs authority accused local media of sensationalizing the issue unnecessarily.

Thousands of cars, SUVs and other vehicles were washed out to sea or covered in radioactive water after the Fukushima Nuclear Plant was crippled both by the quake and the tsunami. Contaminated water poured into the Ocean for days, severely polluting the area and reducing it to a virtual ghost town.

As an indication of how some other countries are region are treating Japanese imports, Russian authorities recently turned away a shipment of 132 cars from Japan after these had also tested positive for high levels of radiation.

http://www.caribbeanlifenews.com/assets/scripts/putclick.x?c=990&ad=2688&pub=carib&redir=http://www.urgentcareinbrooklyn.com

Jamaican Customs spokeswoman Velma Ricketts said the island, which is a major marine transshipment port, is lucky that the U.S. Department of Energy regularly monitors its work and that the country has sophisticated equipment to test for radiation.

“Once it is confirmed to be outside the acceptable levels, the shipment will not be released. There are a lot of things we are doing that people don’t know. We are very vigilant,” Customs Chief Richard Reese said.

Thorium, a slightly radioactive metal that occurs in rocks and soils, may hold significant

promise as a replacement for uranium in the nuclear energy sector.

As global energy consumption increases, thorium is being looked into as a possiblealternative to

uranium to provide safe and abundant nuclear power at a reasonable cost. For example, India has

been interested inthorium-based nuclear energy for decades, according to the US Geological

Survey.

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Thorium in the works

The question of whether thorium works for energy production was answered in 2013, when a private

Norwegian compan, Thor Energy, began to produce power at its Halden test reactor in Norway using

thorium.

“It is the fundamental first step in the thorium evolution,” Thor Energy’s CEO, Oystein Asphjell, told

Reuters.

Nuclear giant Westinghouse, a unit of Toshiba, is part of an international consortium that Thor

Energy established to fund and manage the experiments.

As part of its ongoing research into thorium as a nuclear fuel, Thor Energy created an international

consortium that is charged with funding and managing thorium experiments. One of the consortium’s

members is none other than Westinghouse, an established player in nuclear energy; the company

provides viewpoints on the research.

But Thor Energy is not the only company engaged in researching whether or not thorium is a viable

alternative to uranium in nuclear energy. Firms from the US, Australia and the Czech Republic are

also working on thorium reactor designs and other elements of fuel technology using the metal.

However, Thor Energy was the first off the block to begin energy production with thorium.

How thorium energy works

Unlike uranium, thorium can’t split to make a nuclear chain reaction — in scientific terms, it isn’t

fissile. However, if it is bombarded by neutrons from a fuel that is fissile, like uranium-235 or

plutonium-239, it’s converted to uranium-233, itself an excellent nuclear fuel. After the process

begins, it’s self-sustaining — fission of uranium-233 turns more thorium nearby into the same

nuclear fuel. There are complexities beyond the scope of this article, including the mechanics of

molten-salt versus pressurized-water reactors in burning thorium, but the reaction described above

is the main appeal of thorium, and its principal promise.

Thorium vs. uranium

Thorium is an appealing alternative to uranium to many countries. It is both more cheap and more

abundant than uranium, whose price is expected to rise yet more as backlash from the Fukushima

disaster dies down, according to Energy and Capital. There are other benefits of thorium as well.

During a thorium-powered nuclear reaction, most of the thorium itself is consumed, which leads to

less waste, most of which is rendered non-hazardous in 30 years. The most dangerous nuclear

waste material currently in use must be stored for 10,000 years, by way of contrast. Furthermore, 1

metric ton of thorium is equal to 250 metric tons in terms of efficiency in a water reactor.

Extraction of thorium would be less expensive per unit of energy than extraction of uranium as well,

because it is present in higher concentrations by weight than the other metal, according to

Dauvergne. The source also mentions another peculiar trait of thorium: it is nearly impossible to

weaponize, as it contains no fissile isotope. This in itself has slowed uranium research, according to

a 1997 international scientific symposium on nuclear fuel cycles.

The dangers of uranium – widely publicized in the wake of the Fukushima disaster – often lead

analysts and others to consider thorium more seriously. As thorium is not fissile on its own,reactions

could be stopped in case of emergency, according to Forbes. The publication suggests thorium

could allow countries like Iran and North Korea to benefit from nuclear power without causing

concern that they are secretly developing nuclear weapons, as well.

Thorium can also be used together with conventional uranium-based nuclear power generation,

meaning a thriving thorium industry would not necessarily make uranium obsolete.

Where thorium is found

Thorium is present in small quantities in soils and rocks everywhere, and it’s estimated to be about

four times more plentiful than uranium. Large reserves, rather than the trace amounts of the metal in

the average backyard, exist in China, Australia, the US, Turkey, India and Norway, according to

Reuters.

The US Geological Survey compiled a document listing its domestic thorium resources. The metal is

found in epigenetic vein deposits, low-grade deposits and black sand placer deposits. In its many

locations, thorium can be found in Montana, Idaho, Colorado, the Carolinas, Florida and Georgia.

This is a huge range of locations for possible thorium exploration, development and production.

Of course, the US is not the only country with sizable thorium reserves. The others listed above also

have plenty of options should energy and resource companies decide to develop the thorium

reserves within their borders.

Nuclear Energy

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Transcript of Nuclear Energy