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BLINKSONIC° // ENSEMBLES FOR REAKTOR 6

In , four years after the original release, the film was entirely re-rendered in stereoscopic 3D by Wolfgang Draxinger. The project was announced to the public in mid-September on BlenderNation, [10] and premiered at the Blender Conference. The stereoscopic version was rendered in Digital Cinema Package DCP 2K flat resolution, with a slightly wider aspect format which required adjustment of the camera lens parameter in every shot.

Many scenes in the original production files used flat 2D matte paintings which were integrated into the rendered images during the compositing phase. For the 3D production each matte painting had to be manipulated or entirely recreated into versions for each eye.

Draxinger implemented a number of stereoscopic features in Blender to aid in the stereoscopic production process. However, these features were never merged into official versions of the Blender software.

From Wikipedia, the free encyclopedia. Release date. Running time. Retrieved Making of Elephants Dream ogv Motion picture. Event occurs at 11 minutes 50 seconds until 13 minutes 10 seconds.

September 28, Retrieved May 5, Archived from the original on April 18, Retrieved April 12, Retrieved December 16, October 28, They in general have the disadvantage of requiring complex systems of cascading of individual separating elements to minimize energy consumption. In effect, aerodynamic processes can be considered as non-rotating centrifuges. Enhancement of the centrifugal forces is achieved by dilution of UF 6 with hydrogen or helium as a carrier gas achieving a much higher flow velocity for the gas than could be obtained using pure uranium hexafluoride.

The Uranium Enrichment Corporation of South Africa UCOR developed and deployed the continuous Helikon vortex separation cascade for high production rate low-enrichment and the substantially different semi-batch Pelsakon low production rate high enrichment cascade both using a particular vortex tube separator design, and both embodied in industrial plant. However all methods have high energy consumption and substantial requirements for removal of waste heat; none is currently still in use.

In the electromagnetic isotope separation process EMIS , metallic uranium is first vaporized, and then ionized to positively charged ions.

The cations are then accelerated and subsequently deflected by magnetic fields onto their respective collection targets. A production-scale mass spectrometer named the Calutron was developed during World War II that provided some of the U used for the Little Boy nuclear bomb, which was dropped over Hiroshima in Properly the term ‘Calutron’ applies to a multistage device arranged in a large oval around a powerful electromagnet.

Electromagnetic isotope separation has been largely abandoned in favour of more effective methods. One chemical process has been demonstrated to pilot plant stage but not used for production. An ion-exchange process was developed by the Asahi Chemical Company in Japan that applies similar chemistry but effects separation on a proprietary resin ion-exchange column. Plasma separation process PSP describes a technique that makes use of superconducting magnets and plasma physics.

In this process, the principle of ion cyclotron resonance is used to selectively energize the U isotope in a plasma containing a mix of ions. Funding for RCI was drastically reduced in , and the program was suspended around , although RCI is still used for stable isotope separation. Separative work is not energy. The same amount of separative work will require different amounts of energy depending on the efficiency of the separation technology.

In addition to the separative work units provided by an enrichment facility, the other important parameter to be considered is the mass of natural uranium NU that is needed to yield a desired mass of enriched uranium. As with the number of SWUs, the amount of feed material required will also depend on the level of enrichment desired and upon the amount of U that ends up in the depleted uranium.

However, unlike the number of SWUs required during enrichment, which increases with decreasing levels of U in the depleted stream, the amount of NU needed will decrease with decreasing levels of U that end up in the DU.

For example, in the enrichment of LEU for use in a light water reactor it is typical for the enriched stream to contain 3. On the other hand, if the depleted stream had only 0. Because the amount of NU required and the number of SWUs required during enrichment change in opposite directions, if NU is cheap and enrichment services are more expensive, then the operators will typically choose to allow more U to be left in the DU stream whereas if NU is more expensive and enrichment is less so, then they would choose the opposite.

When converting uranium hexafluoride, hex for short to metal,. The opposite of enriching is downblending; surplus HEU can be downblended to LEU to make it suitable for use in commercial nuclear fuel. High concentrations of U are a byproduct from irradiation in a reactor and may be contained in the HEU, depending on its manufacturing history. The production of U is thus unavoidable in any thermal neutron reactor with U fuel. HEU reprocessed from nuclear weapons material production reactors with an U assay of approx.

While U also absorbs neutrons, it is a fertile material that is turned into fissile U upon neutron absorption. If U absorbs a neutron, the resulting short-lived U beta decays to Np , which is not usable in thermal neutron reactors but can be chemically separated from spent fuel to be disposed of as waste or to be transmutated into Pu for use in nuclear batteries in special reactors.

So, the HEU downblending generally cannot contribute to the waste management problem posed by the existing large stockpiles of depleted uranium. At present, 95 percent of the world’s stocks of depleted uranium remain in secure storage. From through mid, tonnes of high-enriched uranium enough for 10, warheads was recycled into low-enriched-uranium.

The goal is to recycle tonnes by The United States Enrichment Corporation has been involved in the disposition of a portion of the Through the U. Countries that had enrichment programs in the past include Libya and South Africa, although Libya’s facility was never operational.

During the Manhattan Project , weapons-grade highly enriched uranium was given the codename oralloy , a shortened version of Oak Ridge alloy, after the location of the plants where the uranium was enriched. From Wikipedia, the free encyclopedia. Uranium in which isotope separation has been used to increase its proportion of uranium Main article: Reprocessed uranium. Main article: Gaseous diffusion. Main article: Gas centrifuge. Main article: Calutron.

Further information: Separative work units. Retrieved 5 February Nuclear Energy Today. OECD Publishing. ISBN Proceedings of international forum on illegal nuclear traffic. Archived from the original PDF on 22 July June Retrieved 1 July Princeton University. Retrieved 18 April March Oak Ridge National Laboratories. Molten-salt-fueled reactors MSRs supply the nuclear fuel mixed into a molten salt. They should not be confused with designs that use a molten salt for cooling only fluoride high-temperature reactors, FHRs and still have a solid fuel.

LFTRs are defined by the use of fluoride fuel salts and the breeding of thorium into uranium in the thermal neutron spectrum. The LFTR has recently been the subject of a renewed interest worldwide. LFTRs differ from other power reactors in almost every aspect: they use thorium that is turned into uranium, instead of using uranium directly; they are refueled by pumping without shutdown. These distinctive characteristics give rise to many potential advantages, as well as design challenges.

By , eight years after the discovery of nuclear fission , three fissile isotopes had been publicly identified for use as nuclear fuel : [6] [7]. Th, U and U are primordial nuclides , having existed in their current form for over 4. For technical and historical [11] reasons, the three are each associated with different reactor types. U is the world’s primary nuclear fuel and is usually used in light water reactors. Alvin M. At ORNL, two prototype molten salt reactors were successfully designed, constructed and operated.

Both test reactors used liquid fluoride fuel salts. In a nuclear power reactor , there are two types of fuel. The first is fissile material, which splits when hit by neutrons , releasing a large amount of energy and also releasing two or three new neutrons.

These can split more fissile material, resulting in a continued chain reaction. Examples of fissile fuels are U, U and Pu The second type of fuel is called fertile. Examples of fertile fuel are Th mined thorium and U mined uranium. In order to become fissile these nuclides must first absorb a neutron that’s been produced in the process of fission, to become Th and U respectively.

After two sequential beta decays , they transmute into fissile isotopes U and Pu respectively. This process is called breeding. All reactors breed some fuel this way, [17] but today’s solid fueled thermal reactors don’t breed enough new fuel from the fertile to make up for the amount of fissile they consume. This is because today’s reactors use the mined uranium-plutonium cycle in a moderated neutron spectrum. Such a fuel cycle, using slowed down neutrons, gives back less than 2 new neutrons from fissioning the bred plutonium.

Since 1 neutron is required to sustain the fission reaction, this leaves a budget of less than 1 neutron per fission to breed new fuel. In addition, the materials in the core such as metals, moderators and fission products absorb some neutrons, leaving too few neutrons to breed enough fuel to continue operating the reactor. As a consequence they must add new fissile fuel periodically and swap out some of the old fuel to make room for the new fuel.

In a reactor that breeds at least as much new fuel as it consumes, it is not necessary to add new fissile fuel. Only new fertile fuel is added, which breeds to fissile inside the reactor. In addition the fission products need to be removed. This type of reactor is called a breeder reactor. If it breeds just as much new fissile from fertile to keep operating indefinitely, it is called a break-even breeder or isobreeder. A LFTR is usually designed as a breeder reactor: thorium goes in, fission products come out.

Reactors that use the uranium-plutonium fuel cycle require fast reactors to sustain breeding, because only with fast moving neutrons does the fission process provide more than 2 neutrons per fission. With thorium, it is possible to breed using a thermal reactor. This was proven to work in the Shippingport Atomic Power Station , whose final fuel load bred slightly more fissile from thorium than it consumed, despite being a fairly standard light water reactor. Thermal reactors require less of the expensive fissile fuel to start, but are more sensitive to fission products left in the core.

There are two ways to configure a breeder reactor to do the required breeding. One can place the fertile and fissile fuel together, so breeding and splitting occurs in the same place. Alternatively, fissile and fertile can be separated.

The latter is known as core-and-blanket, because a fissile core produces the heat and neutrons while a separate blanket does all the breeding. Oak Ridge investigated both ways to make a breeder for their molten salt breeder reactor. Because the fuel is liquid, they are called the “single fluid” and “two fluid” thorium thermal breeder molten salt reactors. The one-fluid design includes a large reactor vessel filled with fluoride salt containing thorium and uranium.

Graphite rods immersed in the salt function as a moderator and to guide the flow of salt. In the ORNL MSBR molten salt breeder reactor design [18] a reduced amount of graphite near the edge of the reactor core would make the outer region under-moderated, and increased the capture of neutrons there by the thorium.

With this arrangement, most of the neutrons were generated at some distance from the reactor boundary, and reduced the neutron leakage to an acceptable level. In a breeder configuration, extensive fuel processing was specified to remove fission products from the fuel salt.

The MSRE was a core region only prototype reactor. According to estimates of Japanese scientists, a single fluid LFTR program could be achieved through a relatively modest investment of roughly — million dollars over 5—10 years to fund research to fill minor technical gaps and build a small reactor prototype comparable to the MSRE. The two-fluid design is mechanically more complicated than the “single fluid” reactor design. The “two fluid” reactor has a high-neutron-density core that burns uranium from the thorium fuel cycle.

A separate blanket of thorium salt absorbs neutrons and slowly converts its thorium to protactinium Protactinium can be left in the blanket region where neutron flux is lower, so that it slowly decays to U fissile fuel, [23] rather than capture neutrons. This bred fissile U can be recovered by injecting additional fluorine to create uranium hexafluoride, a gas which can be captured as it comes out of solution.

Once reduced again to uranium tetrafluoride, a solid, it can be mixed into the core salt medium to fission. The core’s salt is also purified, first by fluorination to remove uranium, then vacuum distillation to remove and reuse the carrier salts. The still bottoms left after the distillation are the fission products waste of a LFTR.

One weakness of the two-fluid design is the necessity of periodically replacing the core-blanket barrier due to fast neutron damage. The effect of neutron radiation on graphite is to slowly shrink and then swell it, causing an increase in porosity and a deterioration in physical properties. Another weakness of the two-fluid design is its complex plumbing.

ORNL thought a complex interleaving of core and blanket tubes was necessary to achieve a high power level with acceptably low power density.

However, more recent research has questioned the need for ORNL’s complex interleaving graphite tubing, suggesting a simple elongated tube-in-shell reactor that would allow high power output without complex tubing, accommodate thermal expansion, and permit tube replacement. A two fluid reactor that has thorium in the fuel salt is sometimes called a “one and a half fluid” reactor, or 1. Like the 1 fluid reactor, it has thorium in the fuel salt, which complicates the fuel processing.

And yet, like the 2 fluid reactor, it can use a highly effective separate blanket to absorb neutrons that leak from the core.

The added disadvantage of keeping the fluids separate using a barrier remains, but with thorium present in the fuel salt there are fewer neutrons that must pass through this barrier into the blanket fluid. This results in less damage to the barrier. Any leak in the barrier would also be of lower consequence, as the processing system must already deal with thorium in the core. The main design question when deciding between a one and a half or two fluid LFTR is whether a more complicated reprocessing or a more demanding structural barrier will be easier to solve.

In addition to electricity generation , concentrated thermal energy from the high-temperature LFTR can be used as high-grade industrial process heat for many uses, such as ammonia production with the Haber process or thermal Hydrogen production by water splitting, eliminating the efficiency loss of first converting to electricity. The Rankine cycle is the most basic thermodynamic power cycle.

The simplest cycle consists of a steam generator , a turbine, a condenser, and a pump. The working fluid is usually water. A Rankine power conversion system coupled to a LFTR could take advantage of increased steam temperature to improve its thermal efficiency. The Brayton cycle generator has a much smaller footprint than the Rankine cycle, lower cost and higher thermal efficiency, but requires higher operating temperatures. It is therefore particularly suitable for use with a LFTR.

The working gas can be helium, nitrogen, or carbon dioxide. The low-pressure warm gas is cooled in an ambient cooler. The low-pressure cold gas is compressed to the high-pressure of the system. The high-pressure working gas is expanded in a turbine to produce power. Often the turbine and the compressor are mechanically connected through a single shaft. A Brayton cycle heat engine can operate at lower pressure with wider diameter piping. The LFTR needs a mechanism to remove the fission products from the fuel.

Fission products left in the reactor absorb neutrons and thus reduce neutron economy. This is especially important in the thorium fuel cycle with few spare neutrons and a thermal neutron spectrum, where absorption is strong. The minimum requirement is to recover the valuable fissile material from used fuel. Removal of fission products is similar to reprocessing of solid fuel elements; by chemical or physical means, the valuable fissile fuel is separated from the waste fission products.

Ideally the fertile fuel thorium or U and other fuel components e. However, for economic reasons they may also end up in the waste. On site processing is planned to work continuously, cleaning a small fraction of the salt every day and sending it back to the reactor. There is no need to make the fuel salt very clean; the purpose is to keep the concentration of fission products and other impurities e.

The concentrations of some of the rare earth elements must be especially kept low, as they have a large absorption cross section. Some other elements with a small cross section like Cs or Zr may accumulate over years of operation before they are removed. As the fuel of a LFTR is a molten salt mixture, it is attractive to use pyroprocessing , high temperature methods working directly with the hot molten salt.