Iran defiant | as U.N. nuclear | talks fail

United States criticized Iran for failing the mission of the latest International Atomic Energy Agency, saying Tehran was again demonstrated refusal to comply with international obligations on its nuclear program.

International Atomic Energy Agency (IAEA) admitted its failure to investigate Iran's efforts to develop nuclear weapons. This statement came out shortly after Iran said it would conduct preemptive attacks against those who threaten its interests.

Failure of two-day visit by the IAEA could hinder any resumption of nuclear talks between Iran wider and six world powers - the United States, China, Russia, Britain, France and Germany - as a growing sense that Tehran feels it is cornered.
Iran rejects accusations that its nuclear program is a covert attempt to develop nuclear weapons capability, saying it was trying to produce electricity only. But last November, the IAEA said Iran bahwaw information they have run a series of test "relevant to the development of a nuclear explosive devices".

The collapse of the nuclear talks came as Iran seems increasingly isolated, with some experts see the Islamic republic mounting dissent in response to sanctions against the oil industry and financial institutions as proof that it was in no mood to compromise with the West.

In Jerusalem, Israeli Foreign Minister Avigdor Lieberman rejected an appeal by the world powers to avoid pre-emptive attack against Iran's nuclear program. IAEA mission failure can increase the likelihood of an attack by Israel against Iran, some analysts say.

Evaluation of the IAEA inspection team for their visit Iran's nuclear program may be released later in February.

This makes the U.S. and the EU to tighten sanctions against Iran, including a policy to stop the import of crude oil from Iran.

This strain also led to speculation that Israel might conduct a military attack on Iran's nuclear facilities.

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Potential Biodiesel

Advantages Biodiesel Use

1. Generated from renewable energy resources and the availability of raw materials is assured

2. High cetane number (number that indicates whether or not the measure of the quality of diesel fuel based on the nature of the speed of the engine combustion chamber)

3. High viscosity so as to have better lubrication properties than diesel fuel thereby extending the life of the machine

4. Can be produced locally

5. Has a low sulfur content

6. Lower levels of smoke opasiti

7. Lowering exhaust emissions

8. Blending biodiesel with petroleum diesel to improve biodegradibility petroleum diesel to 500%
Biodiesel Raw Materials
Biodiesel is a diesel motor fuel in the form of ester alkyl / alkyl fatty acids (usually methyl ester) are made from vegetable oils or trans-esterification process. stilah biodiesel fuel is identical to the pure. Biodiesel blend (BXX) is as much as XX `% biodiesel mixed with diesel fuel number 1-XX%
Background The need for Biodiesel in Indonesia:

Diesel fuel in the form of methyl ester / ethyl fatty acids. Made from vegetable oils-fats with the metanolisis / etanolisis. -Too products: glycerin. Or from fatty acids (free) by the esterifi-cation with methanol / ethanol. -Too products: water Compatible with diesel fuel, lubricating helpless better. Yield of sulfur is almost nil, generally <15 ppm. BXX = camp. XX-vol% biodiesel with (100 - XX)-vol% diesel. Example: B5, B20, B100. Was effective to improve the quality of diesel vehicle emissions in the B2 level!. Vegetable oil as the main source of biodiesel can be satisfied by a wide variety of plant species dependent on primary resource that is widely available at a place / country. Indonesia has many resources for biodiesel feedstock. Biodiesel fuel is a clean burning alternative fuel That comes from 100% renewable resources. Many people believe That biodiesel is the fuel of the future. Sometimes it is also known as biofuels. Biodiesel does not contain petroleum, petroleum but can be mixed to Produce a blend of biodiesel (eg B20, B50) That can be used in many different vehicles. Pure biodiesel fuel (ie. B100) though, can only be used in diesel engines. Biodiesel is biodegradable and non-toxic, making it so safe That it is even safer than the commonly used table salt! Biodiesel is not alternative fuels like vegetable oil. Biodiesel can be used in its unaltered form in diesel engines. Vegetable oil fuels must be modified and used only in combustion-ignition engines. This makes biodiesel one of the easiest alternative fuels to use. In fact, it is a great option for use on farms in farm equipment. Biodiesel fuel is made through a process called transesterification. This process involves removing the glycerin from the vegetable oil or fat. During the process byproducts are left behind, Including methyl esters and glycerin. Biodiesel is free from Such substances as sulfur and aromatics the which are found in traditional fuels. Compared to other alternative fuels, biodiesel has a number of unique features and qualities. It has passed all the health effects testing requirements, unlike other alternative fuels. This means it meets the standards of the 1990 Clean Air Act Amendments. | The Environmental Protection Agency (EPA) has legally allow biodiesel to be sold and distributed commercially. The rest of the alternative fuels can not be sold commercially as motor fuel Because They do not meet the EPA's fuel specifications. That I believe the biggest feature about biodiesel fuel is that? Is it environmentally-friendly, the which is not found in many traditional fuels. Biodiesel is made from renewable resources, the which means it is safe for the environment. It does not Produce the high emissions like traditional fuels. Biodiesel does not cause harmful effects to the environment That Will Produce positive effects on our future generations. Biodiesel is also good for the economy Because unlike traditional fuels, the resources to the make biodiesel come form within the United States. It is made with products grown in the USA without having to involve politics with other countries. The country can less dependent upon foreign Become countries for fuel supplies and the money goes right back into the U.S. economy. Biodiesel is an innovative fuel FuelBiodiesel That Is Becoming more rapidly available to the general public. It can be found around the country in select places or it can be bought directly from producers. It costs a little more than traditional fuels at the current time Because the demand is not as great. However, as demand Grows and the public realizes the benefits of a biodegradable, renewable fuel source, the price will drop. You can see That the price has already started to drop since it's launched at Their first Biodiesel station. Right now, though, the cheapest way to get biodiesel fuel is to make it at home yourself using a Biodiesel Equipment. Biodiesel equipment can be expensive, I must agree. However, in the long-run, you can actually save a lot of money when you Produce Biodiesel a good blend for your car. Make biodiesel

When the oil used to fry the event of oxidation, hydrolysis of the oil molecules break down into acids. This process is getting bigger with the high heating and a long time during the frying of food. The presence of free fatty acids in cooking oil is not good for health. FFA can also be ester when reacted with methanol, while if it reacts with the soda will mebentuk soap. The product must be purified from biodiesel byproduct, glycerin, soap and soda residual methanol. The rest are on the soda can henghidrolisa biodiesel and biodiesel break into FFA are then dissolved in biodiesel itself. FFA content in biodiesel is not good because it can clog the filter or strainer with sediment and become corrosive to metals diesel engines.

On a small scale can be done with 1 liter of cooking oil materials are new or used. Methanol as much as 200 ml or 0.2 liter. Caustic soda or NaOH to 3.5 grams of clean cooking oil, used oil if needed 4.5 grams, or maybe more. This excess is required to neutralize the free fatty acids or FFA is a great deal on used cooking oil. Can also use KOH but it has cost more and required 1.4 times more than soda. The manufacturing process; Soda dissolved in methanol fire and then fed into the heated oil about 55 ° C, stirred rapidly for 15-20 minutes and then left in the cold overnight. Biodiesel will be obtained at the top with a clear yellowish color and a little lower part of the FFA mixture of soap, the rest of the unreacted methanol and glyserin approximately 79 ml. Biodiesel is a yellowish liquid at the top separated easily by pouring and remove the bottom of the liquid. For large-scale bottom product can be purified to obtain a high-priced glycerin, also soap and residual unreacted methanol.

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Radioactive nuclear waste

Radioactive wastes are waste types containing or contaminated with radionuclides at concentrations or activities that exceed the allowable limits (clearance level) established by the Agency for Nuclear Energy. The definitions used in legislation

Understanding others radioactive waste defined as radioactive substances that are no longer applicable, and / or materials and equipment or be exposed to radioactive substances are not radioactive and can be enabled / used. Materials or equipment or be exposed to radioactive likely due to the operation of nuclear installations or installations that utilize ionizing radiation.

Broadly speaking, nuclear waste is divided into two categories, Low Level Waste and Intermediete (LILW) and High Level Waste (HLW). LILW is the nuclear waste in the form of gloves, shoe covers and clothing of workers at nuclear power plants as well as the maintenance of machine tools and the like. Treatment programs so how do LILW stored in temporary storage before being didispose permanently. While generally HLW-treated with 2 methods, dry and wet storages. As the name implies, in wet storage, nuclear waste from reactor-treated in water for 3-5 years to reduce the cooling plus heat from radioactive decays. After passing through that process, the nuclear waste container is inserted into the specially designed so that it can securely store, especially the use of corrosion resistant materials and radiation. While dry storage, nuclear waste is directly inserted into a specially designed container without water as a coolant. Usually stored up to 6 years in the container. Containers can dry storages shaped metal casks, concrete silos, and storage vaults.

More than 90% of the world's nuclear waste currently-treated through a process of wet storage. Generally, the temporary storage of nuclear waste at the nuclear plant itself, so it does not need to be transported through the transport distance. Not random people can come into this facility, because of course the controls are very tight. NPP managers are required to provide periodic reports on the passage of nuclear waste to the local regulatory bodies and also the IAEA.

Treatment can then use a geological repository system, or use a transmutation techniques that today more and more research in the field, such as fast reactors and ADS are predicted to exist several decades to come.
Researchers discover microbes that clean and neutralize nuclear waste and other toxic metal power produced by the microbes themselves.

Researchers from Michigan State University (MSU), said this process could be improved and ultimately benefit the affected sites of nuclear contamination.

The ability of Geobacter microbes are the crippling uranium has been well documented, but the way they do the job right is still a mystery to this day when the researchers claim to find it.

Researchers claim to find nano conductive pili or cables that contribute to the neutralizing ability of these microbes through electrical activity.

"Our findings clearly show, nano wires into the main catalyst of this microbial reduction of uranium," said microbiologist Gemma Reguera from MSU.

This part is very important in performing electroplating with the electric version of the natural uranium, radioactive materials and prevent crippling contaminate ground water, he added.

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Potential Gas Turbine

The efficiency of gas turbines are often planes, helicopters and small, are used for power generation purposes. There are several advantages because it uses a gas turbine.
Electricity generated from gas turbines, 4 or 2 - stroke engine with a motorcycle, is higher than the same weight. Medium containing an equal weight of the gas turbine power, and transportation as mentioned above will no longer widely used and produced by the gas turbine.


How it works Gas Turbine

The major components of gas turbines, there are three. High pressure air compressor to create. Combustion chamber and the combustion air pressure and high-speed serves in a part of the production. Turbine from the high pressure air in the combustion chamber was a function of mechanical motion.
Combustion chamber. The chemical composition of the three elements of air and fuel burning fire. A hydrocarbon fuel is used in gas turbines. From the high pressure air compressor into the combustion chamber, fuel injectors and combustion air pressure is sprayed in production, leading to a higher speed. Turbine used to generate electricity. The existing gas turbine, called a modified turbo. The format is similar to the gas turbine. Turbo - The fan in front of a fan compressor (fan) is.

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Types of Disorders in Plants

Various kinds of disturbances on power
• The drum water level high

As a result of drum level high, then a mixture of steam and water can get into the steam line which can result in damaging the piping system waterhammer.
• The drum water level low
Generally a boiler equipped with automatic safety devices to trip the boiler / power plant unit if the water level in the lower drum, to prevent fatal damage to the boiler. If the water level below the expected glass, and automatic safety is not working normally, is necessary to take action to turn off / stop the boiler.
• Boiler tube failure

Indication of a boiler tube leak, among others: kelaianan sound, the water rises above normal adder, more white chimney smoke, steam sprayers. Try to keep the water level in the drum remained normal. Stop the boiler, because the water / vapor can leak mengkikis adjacent tube so that it can exacerbate the damage
• IDF trip
Generally equipped with interlock, if the IDF and FDF automatically trip the boiler trip, because the FDF and the boiler does not trip the fire would burst out of the baker. If the IDF trip, and the interlock system is not working normally, manually trip FDF
• Loss of ignition
Generally boiler is equipped with a flame detector to monitor the combustion in the combustion chamber. If the flame goes out automatically the supply of fuel will be stopped.
If this happens needs to be done purging the combustion chamber for at least 5 minutes before the start of the next firing, to prevent explosion
• Power failure
If it happens interrupted power supply (voltage loss), it is impossible to spend PULVERIZER coal present in the mill before turning off the boiler. If the mill can not be operated again within 3 hours, then the coal is in the mill to be removed to prevent fires.
• Fire in PULVERIZER
Fire in the mill when the mill operation is rare, but sometimes also the result of coal from the coal bunker was tebakar or primary air temperature is too high. The presence of fire can be detected from a very rapid temperature rise / sharply on the outlet side
• Corrosion / kropos / rust

Corrosion is a threat of an eye the plant / equipment, as it could potentially interfere with the operation, shorten the life of the plant
High-potential equipment corrosion, among others:
a) Equipment in the primary cooling system with cooling sea water medium, the pier. General corrosion of equipment that could potentially include: traveling screen / water intakes, docks, condenser water box. To inhibit the corrosion rate is usually done by means of cathodic protection, among others: Zeng anode / anode victim, inverse current, as well as anti-rust paint
b) Element AH cold side
AH element most susceptible to the cold side corrosion, caused by sulfur in the flue gases condenses, especially if using fuel with high sulfur content.
Efforts to inhibit the corrosion rate is done by controlling the exit flue gas temperature is always above the dew point AH sulfur, among others, by heating the incoming air AH (Air Preheat Coil)
c) Boiler tube
Corrosion of boiler tube can occur due to water quality charger (boiler water) is not good / not pure / contaminated, among others, as a result of leaking condenser tube, oxygen levels within the high water boiler. Solved immediately in the event of condenser tube leak, adjust the water quality of the blowdown and chemical injection. Oxygen levels within the control of boiler water, with a de-aerating and chemical injection.
• slagging and fouling

Slagging and fouling is a threat that could potentially interfere with the operation of the boiler that uses fuel, especially coal. Part boiler slagging and fouling potential occurs are:

.> Furnace slagging
Place of ash slagging / ash melts its temperature exceeds the melting point of ash. Process due to the occurrence of ash attached to the fuel pipes in the room was thick enough to inhibit heat transfer process so that the temperature of the combustion chamber so up and melt the ash. Sediment / deposit this ash is melted down along the pipe boiler stir, then serve frozen / hard when it came to the area which the temperature is cooler.
Great slagging can lead to blockage of ash bridging the hoper. If the clean-up deposit occurs normally require bridging boiler stop. Sootblowing do regularly, to slow the rate of formation of slagging. Sootblower reliability is critical to prevent slagging

.> SH deposit
Abu superheater tube attached to the longer will be more thick, inhibit heat transfer, so that the steam temperature tends to drop. Sootblowing do routinely to menhambat ash deposit rate on SH, and sootblowernya be effective

.> Economiser fouling
Abu also be attached to the tube economiser, even more so when using a finned-tube economisernya. Sootblowing do routinely. Sootblower be effective.

.> AH fouling
Furthermore ashes will stick to the AH, it can even block some element AH. Sootblowing do routinely. Sootblower be effective. Frequency can lead to excessive sootblowing AH seals wear faster, so that air leakage become bigger, decreasing the amount of combustion air and ultimately increase the potential for slagging on boiler combustion chamber

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"Kazakhstan" Domination Of The World's Largest Uranium

Data compiled by foreigners indicate that uranium production worldwide increased from 50 772 tons in 2009 to 53 663 tonnes in 2010, which is the highest number since the early 1990's. Kazakhstan is the country's largest producer, with production reaching 17 803 tonnes in 2010, increased 27% from 14 020 tonnes produced in 2009. Canada and Australia respectively to maintain the second and third place, although the two countries uranium production fell in 2010. While Canadian production down 4% from 10 173 tons in 2009 to 9783 tons in 2010, while Australian production fell 26% from 7982 tonnes in 2009 to 5900 tons.

Two African countries, Namibia and Nigeria - are the largest uranium producer fourth and fifth in 2010, with production of 4496 tons each, and 4198 tons. Cameco Canada back on its position as the company's largest uranium producer in the world with total production of 8758 tons in 2010, up from 8000 tonnes in 2009. Uranium production from this company is 16% of the world's uranium products in 2010.Areva of France, which is a leading producer in 2009 with a production of 8623 tons, has produced 8319 tonnes reported in 2010, and occupied the second place. Position followed by Kazatomprom, which produce 8116 tons in 2010, up from 7467 tonnes in 2009. Although controlling the production of uranium Kazakhstan, Kazatomprom develop a savings fund in partnership with leading companies including those mentioned above. Kazakhstan looks set to hold its position as the largest uranium producing country in 2011. State company Kazatomprom Kazakhstan reported that production during the first quarter of 2011 reached 777.4 tons, 7.3% above the planned production plan that is equal to 724.4 tons and increased by 24% in the same period last year.

Mine Cameco's McArthur River / Key Lake in Canada continue to occupy the position of the largest mines in the world capable of producing uranium in 2010, amounting to 7654 tonnes, up from 7339 tonnes in 2009. Although production fell from 4444 tons in 2009 to 3216 tons in 2010, the mine Energy Resources of Australia (ERA) Ranger Australia in Australia to maintain second place.

Rio Tinto's Rossing mine in Namibia is the third largest mine with a production of 3077 tons in 2010, down from 3520 tonnes in 2009. Although conventional underground mining techniques and remain in an open area, the main method for the extraction of uranium, with 53% of products derived from this technique, the use of technology in-situ leach (ISL) has become populler. In 2009, approximately 36% of uranium extracted using ISL technology, while in 2010 this figure jumped to 41%. Merupkan uranium production by-product of other mineral slightly decreased 7% of total production in 2009 to 5% in 2010.

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Development of nuclear energy systems in the future.

Uranium nuclear are all kinds of material that can be used to produce nuclear energy, as if the analogy with the chemical fuel that is burned to produce energy. Until now, the nuclear fuel that is commonly used fissil heavy elements that can produce nuclear chain reactions in nuclear reactors; nuclear fuel can also mean the material or physical objects (for example fuel bundles composed of fuel rods are prepared by fuel material, can also be mixed with the structural material, moderator material, or material of the reflector (reflector) neturon. fissil nuclear fuel that is used seirng 235 U and 239Pu, and activities related to mining, refining, use and disposal of these materials included in the nuclear fuel cycle. the nuclear fuel cycle is important because it is associated with the presence of nuclear and nuclear weapons.
Not all fuel used in nuclear fission chain reaction. For example, 238Pu and some other light elements are used to generate a number of nuclear power through the process of radioactive decay in radiothermal generator, and an atomic battery. Light isotopes such as 3H (tritium) are used as fuel for nuclear fussi. When looking at the binding energy at a particular isotope, there are a number of energy which can be obtained by the merge elements with atomic numbers less than iron, and memfisikan elements with atomic numbers greater than iron.
The nuclei of U-235 consists of 92 protons and 143 neutrons (92 +143 = 235). When a nucleus of U-235 atom captures a neutron, it will split into two new nuclei and release some energy in the form of heat, accompanied by the release of two or three new neutrons.

If the neutrons are released tersebutdapat trigger the same reaction on other U-235 atoms, releasing neutrons and other new, fission chain reaction can occur. This reaction can happen and happen again, up to a million times, then the heat energy in huge quantities can be produced from a bit of Uranium. Roughly the thermal energy of the core reaction 1 gram U-235 is equal to the heat energy from the combustion of 1 ton of coal.
Closed nuclear fuel cycle through recycling of spent fuel without plutonium separation process has been the top choice of nuclear energy systems development in the future.
A. Mining and Milling
Uranium can be mined by open technique (open cut) and tunnel engineering (underground) depends on the depth of the rocks found uranium. For example, Ranger uranium mine is open while the Olympic Dam mine is an underground mine (mine also produces copper, gold and silver). Both the uranium mines in Australia which is the country with the largest budget category uranium reserves in the world. Mined uranium ore was then sent to the ore processing plant which is generally located near the mine. In this plant, uranium ore is mechanically crushed, and then uranium is separated from other minerals through chemical processes using sulfuric acid solution. The end result of this process in the form of uranium oxide concentrate (U3O8) is often called yellow cake, or "Yellow Cake", although in many ways colored brown.
Some of the uranium mines in Australia, the United States, and Kazakhstan using In Situ Leaching (ISL) uranium directly to mengkstrak of rocks in the soil and bring it to the surface in the form of uranium-rich solution, which is then deposited and dried into a solid uranium oxide. This technique is mainly used to extract uranium found in rocks on the ground that are not economical when delakukan with conventional techniques.
U3O8merupakan commercial products traded on world markets. Ten major countries producing uranium are Canada, Australia, Kazakhstan, Nigeria, Russia, Namibia, South Africa, Ukraine, United States, and Uzbekistan. Canada and Australia produce uranium almost 50% of total world production.
Roughly speaking, it takes about 200 tons of uranium to power a 1000 MWe reactor capable of operating for 1 year. Current world demand for uranium is relatively stable, at around 65 000 tonnes / year.
2. The next steps for the conversion of nuclear fuel-making is a process of purification and conversion into powder Yellow Cake uranium dioxide (UO2) nuclear degree. UO2 is then converted back into gaseous form of uranium hexafluoride (UF6).
For nuclear reactors which use natural uranium fuel, which is a reactor that could produce a chain fission reaction with natural uranium fuel which contains only 0.7% U-235, UO2 powder Yellow Cake conversion results can be directly sent to the plant for processing nuclear fuel a device that is ready to use nuclear fuel in the reactor.
As for the nuclear reactor is only able to produce the fission chain reaction with enriched uranium fuel, UO2 powder conversion process results in the Yellow Cake needs to be changed into the form of UF6 as feed gas enrichment process (the process of increasing levels of U-235 in uranium fuel).
UF6 conversion of UO2 to be done in a two-step process. The first is the reaction of UO2 with anhydrous HF acid to be uranium tetrafluoride (UF4). UF4 and then reacted with F2 to form UF6 gas.
The main countries operating commercial plant converting Yellow Cake - UF6adalah Canada, France, the United States, Britain, and Russia. Some countries such as China, India, Aragentina, and Romania also operates a factory conversion but only for part of its own pass unrecognized.
3. Enrichment
The majority of nuclear power plants now operating or under construction require enriched uranium as fuel. Uranium enrichment is the process of increasing levels of U-235 in uranium fuel from 0.7% (U-235 content in natural uranium) to about 3-5% or more.
Enrichment process discard about 85% U-238 through the separation process of UF6 gas into two streams, one stream is the enriched uranium will be used bait and fuel fabrication process. While the other stream is the stream of waste or "tailings" of the flow of impoverished uranium U-235 is referred to as the depletion of uranium (U-235 content less than 0.25%).
There are two methods that are commercially used for uranium enrichment process, the method of gas diffusion and gas centrifugation methods. Both of these methods basically use the same principle, namely the weight difference between the atom and U-238 U-235 atom.
In the diffusion method of enrichment, UF6dialirkan gas into a porous membrane. Therefore, the lighter U-235 atoms will diffuse or move faster than U-238 atoms, so that the UF6 gas which passes the membrane will contain more U-235. To achieve the U-235 enrichment level between 3-5%, it takes about 1400 times the repetition of the process. So the method is very wasteful of energy, will consume approximately 3-4% of the electricity it generates.
In the enrichment method of centrifugation, UF6diputar gas with high angular velocity in a tube long and slender (1-2 m long, 15-20 cm diameter). Centrifugal force will throw the isotope U-238 which is heavier away from the center of rotation, while U-235 isotopes of the lighter will be concentrated in the center of rotation.
Gas centrifuge method is more energy efficient and can be built with a smaller unit than the gaseous diffusion method, so the method is more economical and fastest growing commercially.
Uranium enrichment plant in the world was first built in the United States with a gas diffusion method. Some modern enrichment plant in Europe (France, Britain, Germany, the Netherlands) and Russian gas centrifuge method. Other countries that operate a commercial uranium enrichment plant is Japan, China, Argentina, and Brazil.
Several types of nuclear power plants, especially nuclear power plants in Canada and the Opium early generation nuclear power plants with gas cooled reactors in the UK do not require enriched uranium fuel.
4. Fuel Fabrication
Fabrication of fuel or nuclear device begins with the conversion process UF6yang been enriched (enrichment plant output) into uranium dioxide powder (UO2) is then formed into pills (pellet) cylinders through pressing and continued with roasting in an atmosphere of hydrogen gas at high temperatures (1700 ° C) to pellet UO2berderajat membetuk dense and strong ceramic.
Pellet-pellet UO2yang meet the quality requirements and then put into a shell of zirconium alloy material (zircalloy).
After both ends of the sleeve and welded closed, the fuel rod (fuel rod) arranged to form a combustion device (fuel assembly).
1000 MWe PWR core contains fuel about 160 devices. Total fuel rods are used to reach 42 000 units. Each fuel rod contains about 300-370 pellets of UO2 pellets, each weighing 6-7 grams.
PWR fuel plant the largest in the world include the Westinghouse - USA with a production capacity of 1600 ton / year, Global Nuclear Fuel - Americas with a production capacity of 1200 ton / year, Ulba - Kazakhstan with a capacity of 2000 ton / year, TVEL Elektrosal - Russia production capacity of 1020 ton / year, TVEL Novosibirsk - Russia with a production capacity of 1000 ton / year, and FBFC - France with a production capacity of 820 tons / year.
Other countries operating nuclear power plants also produce fuel perangka are Japan, South Korea, China, India, Argentina, Brazil, Britain (UK), etc.. . Nuclear Reactor
After the fabrication process, the nuclear fuel put into the reactor core. The composition of the fuel (fuel assembly) that has shaped the structure of the core or core reactor (reactor core). PWR type nuclear power plants with 1000 MW of electrical power (MWe) contains approximately 75 tonnes of slightly enriched uranium. In the reactor core, U-235 fission experience and generate heat in a continuous process called fission chain reaction. Continuity of this process depends on the moderator such as water or graphite, and fully controlled by using control rods.
In the reactor core, a number of U-238 will absorb neutrons and fission results turned into plutonium (Pu-239).
Half of the plutonium produced is also experiencing a fission reaction and produces a third of the total energy of the reactor. To maintain the performance of the reactor, about a third of the fuel used in the core should be replaced with new fuel every year or every 18 months.
6. Temporary Storage of Spent Fuel highly radioactive used fuel and spend a lot of heat. For safe handling and safe, a new spent fuel from reactors dikelurakan stored in special ponds near the reactor to reduce the heat and radioactivity. Water in the pond serves as a barrier to radiation and heat transfer spent fuel from Baban.
Spent fuel can be stored in the storage pool for a long time (up to fifty years or more), before being reprocessed or sent to final disposal as waste (sustainable storage).
Alternatively, after the level of radioactivity and heat emission decreases drastically spent fuel, spent fuel can be removed from the storage pool and then stored in a dry way. Radiation shields are reasonably priced and maintenance-free natural cooling, making this way to be an attractive option.
7. Reprocessing (Sports Birthday)
Spent fuel still contains approximately 96% (480 kg) of uranium with a fissile material content of U-235 is less than 1%. Then 3% (15 kg) of spent fuel of fission products can be categorized as high-activity waste, and 1% (5 kg) the rest of the plutonium (Pu) produced during the fuel inside the reactor and did not experience the burning.
Separation of uranium and plutonium from fission products is done by cutting the fuel element and then dissolving into the acid. Uranium is obtained from the separation process can be converted back into uranium enrichment hexaflourida for later performed. The obtained plutonium can be blended with enriched uranium to produce MOX fuel (Mixed Oxide).
Commercial MOX fuel plant in the world is Belgium, France, Germany, Britain, Russia, Japan, China, and India. United States does not do again if the spent fuel for commercial nuclear power plants in the country. Until now the United States adheres to an open cycle systems or "open cycle".
Some of the PWR nuclear power plant in the world especially in Europe have been using MOX fuel, although its nature is still partial, namely 20-30% of the existing fuel in the core. Japan in the near future it plans to ship a third of its 54 nuclear power plants with MOX fuel.
The 3% of highly radioactive waste resulting from reprocessing is a fission product which number around 750 kg per year from 1000 MWe power reactor. This waste is initially stored in liquid form and then compacted.
Reprocessing spent fuel conducted at facilities in Europe and Russia with a capacity of 5000 tons per year, and total production for almost 40 years has reached about 90 000 tons.
8. Vitrification
High radioactivity waste from reprocessing can be calcined (heated at very high temperatures) so that a dry powder which is then put into borosilicate (pyrex) for immobilizing the waste. Glass material is then poured into stainless steel tubes, each of 400 kg of waste glass. Pengoperasiaan 1000 MWe reactor for one year will result in the waste glass as much as 5 tons or about 12 tubes of stainless high as 1.3 meters and 0.4 meters in diameter. Once given appropriate radiation protection, waste is processed and then transported to the waste storage area.
Until now, the nuclear fuel cycle back end or the "back end" just get to this point.
Final disposal of high radioactivity waste or spent fuel disposal is not reprocessed (open cycle), is still not done.
9. Final Disposal of Waste
Final disposal of waste is in principle sustainable waste storage of high radioactivity that has digelasifikasi and sealed in a stainless steel tube, as well as sustainable storage of spent fuel that has been through enough and the cooling process has been sealed in a container or "canister" is made of corrosion resistant metal such as copper or stainless steel.
Has generally been accepted that the waste is planned to be buried in stable rock in the soil to a depth of not less than 500 m in bedrock (bed rock). Most countries plan to implement the sustainable storage of spent fuel after 2010.

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