FR2999329A1 - Suction device i.e. collecting container, for use in e.g. drone, for suction of nuclear cloud outputted from accident of nuclear power plant, has container provided for recovery of condensates, and base allowing storage of device on ground - Google Patents

Abstract

The device has a suction pump or turbine (2), and a suction mouth (1), which is provided with a protection grid turbine. An electronic purifying tank (3) purges condensates. A compressor (4) includes a filter for filtering compressed air. A purging circuit (5) is provided with automatic valves. A radioactive compressed-air container (6) has a minimum capacity of 5000 liters, and a resistance to a pressure of 16 barometric pressures. A matrix container (7) is provided for recovery of the condensates. A base (8) allows vertical storage of the device on a ground.

Description

TECHNICAL FIELD OF THE INVENTION This concept of combating radioactive clouds arising from accidents at nuclear power plants is mainly based on the use of aerial means. Collecting planes or helicopters in the form of drones or large 5 "secure transporters (propulsion, radiation, heat ..) equipped with large or medium capacity tanks, serving as receptors for confining the radioactive particles of the nuclear cloud. be also used, after some modifications of the receiver tanks, to suck up a volcanic cloud, or a cloud 4.0 from a major fire.The last two clouds (volcanic and incendiary), composed mainly of non-radioactive ash, do not present the same need for containment, storage and treatment, so we will base ourselves on essentially examining this concept for the use and aspiration of a nuclear cloud. -is This nuclear cloud, which can be tinted by the sending of coloring particles, to better locate it, would be sucked and compressed in high pressure tanks (carbon for example) fixed the aircraft carrier so that they can be automatically disconnected after filling and landing, and then replaced by other empty tanks to take off again for a new suction rotation (cloud collection). It is obvious that the number of these planes or helicopters collectors, and their implementation, would depend on the importance of the radioactive cloud, weather requirements, and other hazards, (such as the use of naval means for recovery above seas and oceans). These planes or helicopters collectors, e.S could constitute a real air fleet, like the current Canadairs, for the fight of the fire. Once deposited on the ground these tanks would be stored and secured on a storage area provided for this purpose. These storage areas should be provided as part of the contingency plans and major risk management of each nuclear power plant. It goes without saying that these predefined zones would be as far as possible away from cities and agglomerations, in a sufficiently wide radius, for safety against the risks of the power plant (between 30 and 50 km) and also close enough to facilitate the rotations of the plants. collector aircraft. 35 During the collection of the radioactive cloud over the seas or oceans, and far from the coasts, a logistical support will be necessary, in the form of naval means to implement (aircraft carrier for the planes or helicopters collectors, and large carriers of the type tankers for the storage of tanks collected in flight) This set of air, naval, and land means, is the major concept tic) Patent. It should be noted that, given the existing resources available (air and naval), which are immediately available, the project could be implemented very quickly, at the level of countries interested in such a concept, and would allow JAPAN, for example, to preserve possible and foreseeable risks that may still occur. For other countries, the idea of creating such a device, a real force to fight against atmospheric nuclear accidents, would be a major and reassuring asset for the populations already worried by the catastrophe of Japan and its procession of consequences more or less harmful (radioactive cloud having circumnavigated the planet) STATE OF THE PRIOR ART: Within the framework of our innovative invention, a suitable project could very quickly see the light of day (adaptations of the collection or collection tanks of the radioactive cloud, with automated fixing system, for replacement - full tank / empty tank - fast).

It may also be considered air support, a fixed suction unit (Drone helicopter) above the plant, and the starting point of the cloud. This fixed suction system (in the form of a large funnel) would suck the cloud to bring it back to the ground via a sheath (a pipe of varying lengths of flexible elements that can be connected to each other) to be fixed to storage tanks. earth, very large capacity.

DETAILED DESCRIPTION OF THE INVENTION ASPIRATION OF THE CLOUD BY TURBINES: The suction is produced by a depression generated by a pump or turbine. The suction speed must be sufficient to carry the transport of radioactive particles, with a sufficient flow respecting the standards. This aspiration of polluted air will be compressed in collection tanks. Packages to trap radioactivity inside the collection tanks: The long-term containment of the radioactive atoms contained in the packages is essentially ensured by the resistance of the matrices to their two main 40 enemies: the water and the irradiation of the radiations produced in their breast. Research has established patterns of release of radioelements for each containment matrix in a variety of situations. Conditioning is confining the radioactivity and immobilizing the radioactive atoms. These atoms must be immobilized until they are no longer radioactive, or if this is not possible until they are almost no more. This conditioning, its ability to resist the aggressions of radiation naturally depend on the activity of the material to be treated. This activity is the most important for spent fuel from nuclear power plants. During the operation of a reactor, the confinement of the radioactivity is ensured by zirconium sheaths, tubes which coat the fuel pellets. After the unloading of the collection tanks, it will be these same ducts that will have to provide the first containment barrier. To reinforce this barrier, it is planned to insert the spent fuel assemblies into specialized containers called cases or castles. S In the case where the used fuel is withdrawn, the confinement relates to the residue of highly radioactive materials considered as waste. The radioactive residue is incorporated in a material, called "matrix", chosen for its resistance to damage caused by irradiation. These matrices must be able to incorporate a sufficient quantity of radioactive atoms. They are asked to resist dissolution in water for thousands of years. At present, the La Hague plant is used as a matrix for special glasses for high-level waste. Glass is an amorphous material whose extremely flexible structure absorbs the effect of radiation. Glass is a powerful packaging matrix to accommodate all 3s diversity of fission products. As part of waste research, some more expensive ceramics have been developed with even higher durability performance. These ceramics - mineral compounds elaborated at high temperature - would have the property of being able to incorporate in their crystalline structure atoms with a good chemical compatibility. Long-lived radioactive atoms could thus be perfectly immobilized in these structures which would then constitute customized matrices. We would protect ourselves over very long periods of elements such as iodine-129 and cesium-135 naturally enough mobile that would be difficult to destroy by transmutation. 0 The entire suction mouth, turbine and compressor will be fixed and adapted to the aircraft or helicopter collector. The collection tank (s) connected to this set will be fixed by automatic cleavage, so that they can be quickly removed and replaced, with minimal handling and protected from the radiation that will necessarily be experienced by the overhead collection means. -45 Spiral Air Compressors Spiral air compressors operate by rotating a moving spiral on a fixed spiral. The air entering the engine is compressed by the movement of the moving spiral and sent to the collecting tanks. Polluted Air Treatment, and Purge Systems We propose to adapt, a condensate draining system, to all types of compressor, whether lubricated, scroll or piston Compressor purge systems There are electronic condensate traps, which ensure safe, reliable and economical condensate management. 2.5 Intelligent exhaust function monitors condensate build-up with liquid level sensors and removes condensate only when needed, eliminating waste of compressed air and saving significantly energy. Extremely safe and reliable, these evacuation devices solve all the problems of condensate evacuation, including in the most contaminated systems. The condensate evacuation range includes many models suitable for draining oil-contaminated condensate and can even be equipped with an extra hard coating for oil-free condensates that are more aggressive. Piston compressors without a soundproofing box include a manual drain valve (or purge) for purging the air tank condensate accumulating therein. 6 An automatic purge system may be considered as an option. The product of the purge being recovered by a compartment of the collection tank. The automatic purge consists of a solenoid valve and a timer that allow condensate discharge at regular intervals and at each stop of the compressor. In addition to this automatic purge device, there is a manufacturer who offers a condensate recovery bottle that is installed directly on the compressor and to which the drain pipe of the automatic purge is connected. The filters' automatic drain hoses can also be connected to this recovery bottle. For application on collector aircraft, high pressure carbon tanks could be used, consisting of a carbon fiber filament winding on a thermoplastic liner. The standard operating pressure is 300b, with a 450b test, and rupture tests at pressures greater than -15,700b. These tanks do not present any danger in case of crash because they do not fragment. Their technology is already massively used on vehicles running on natural gas. For the record: In the case of suction intended to transport particles, the transport speed is calculated in relation to the sedimentation rate. We will try to obtain a maximum speed in the ducts and the limit will be imposed by the depression generated by the turbine. Sedimentation velocity is the minimum velocity that a flow must have to carry, rather than deposit, sediment, and is given by Stokes' law: (pr.)) Gr2 Where w is the sedimentation velocity, p is the density (the indices p and f indicate particle and fluid respectively), g is the acceleration due to gravity, r is the radius of the particle and p is the dynamic viscosity of the fluid. A minimum sedimentation velocity warning can thus be set in the pipe sizing interface -I 0 to detect the maximum diameters not to be exceeded in a charged fluid network project. The transport of particles such as the aspiration of residues, dusts, and other materials must be sized according to this sedimentation rate to avoid deposits. 2..5 - 4.5p Better Understanding to Better Understand the Effects of a RADIOACTIVE CLOUD Following our exposure to nuclear radiation from a radioactive cloud, we face risks to our health, ranging from nausea to loss of appetite. diarrhea, infection problems, skin problems, even spinal cord or gland, etc. Recent events in Japan mean that radioactive fumes are commonly released into the atmosphere and arrive regularly to us. They are not safe. But what is the influence on the environment and on us that even governments make available to the public their radioactivity monitoring results, as in the context of the Japan disaster? Catastrophe in Japan: Radioactive emanations escape from Fukushima, the cloud arrives in France .... New plumes of smoke escaped from the reactors of the Fukushima nuclear power plant. All about the radioactive cloud of Fukushima Can the cloud charged with nuclear particles, like that of Chernobyl, affect France. And would it be dangerous? The French are not the only ones to be worried about the possible arrival, over their territory, of the radioactive cloud of the Japanese power station of Fukushima. It is, indeed, all the inhabitants of the planet who scrutinize, day after day, with their nuclear specialists, the progression, in the atmosphere, of the contaminated particles. For the moment, everyone observes with a mixture of anguish and compassion, the desperate efforts of the Japanese technicians who try, day and night, and at any cost, to cool the fuels with sea water. that this titanic fight continues to avoid "the worst scenario" everyone can not help but remember the catastrophe of Tchemobyl. And from his cloud that had traveled Europe to France. From then on, questions of all sorts accumulate and deserve answers. Here are ten. How does the cloud move? The radioactive cloud moves according to its altitude and winds. The higher it is, the more likely it is to go around the Earth. Experts estimate that the discharges are mounted at 3000 meters height before stabilizing at 2000 meters but that it is the winds that will move the cloud more or less far: 3 5 "The height of the cloud was capped at 2000 meters, he can be driven by low-layer winds "," After being released into the atmosphere, the particles are transported by wind and disperse in large amounts of air, 45 35 The speed of their circulation depends on the altitude at which they were projected and their temperature at the reactor outlet. the day of Thursday 17 is "not worrying" because "the winds of north-west are cleaning towards the Pacific Ocean" but announces a more problematic situation for Friday and Saturday with the presence of anticyclones and fog. "Every six hours in any case, the different trajectories of the winds are updated and the evolution of the radioactive cloud is followed very closely," What makes this cloud? The cloud, composed of rare gases and extremely fine metal dust not visible to the naked eye, would carry mainly iodine and cesium 137: 1400 times less active than radioactive iodine, cesium 137 disappears slowly, " The precise composition of the cloud in radioactive particles will also be decisive (for its future): the quantity of iodine is divided by two every eight days, whereas the period is of the order of thirty years for cesium ". Is the radioactive cloud a health hazard in France? This is a question that many people are asking themselves right now ... I even know who are coming out of their homes as little as possible since mid-week and the supposed arrival of the radioactive plume from Fukushima. But do not expect to see a suspicious cloud in the sky ... After Tchemobyl, some are wary of the communication that is made around the Fukushima nuclear disaster. However, it is useless for an individual to invest in a Geiger counter (a price that starts at about 228 E) that does not detect low radioactivity levels and whose results are difficult to interpret by the layman. It must be said that there is something to be skeptical about. One has the impression that whatever the extent of the radioactivity, the authorities will always be reassuring, under scientific guarantee. The climate of suspicion has been reinforced by the revelations of the CRIIRAD (Commission of Independent Research and Information on Radioactivity) which denounces the concealment of results of air radioactivity analyzes and the probable underestimation of those rendered public. (http://www.criirad.org/actualites/dossier2011/japon_bisisommaire.htm I) One thing is certain, the radioactive plume has indeed started to pass over France since Thursday, March 24th. The IRSN (French Institute for Radiation Protection and Nuclear Safety) has detected traces of iodine-131 (0.012 mBq / m3 on average) in the air collected at the top of Puy de Dôme. CRIIRAD thinks that this level of radioactivity is very probably underestimated because the air would have been sampled from an aerosol filter which does not make it possible to trap the gaseous iodine which could constitute the majority of the radioactive iodine present in contaminated air masses. Can we walk by the sea on the French coast without risk this weekend? This is the very serious question that the organizers of the Ocean Initiatives have asked themselves: on the page of the site dedicated to this event, Surfrider Foundation writes that the Institute of Radioprotection and Nuclear Safety indicates that the concentrations will have no consequences on the environment and health and that there is therefore no danger for the organization and participation in the Ocean Initiatives. As the Atlantic Ocean is probably spared for the moment by marine radioactive pollution (unlike the Pacific Ocean), one might think that the sea air is still pure and that its natural iodine content could "protect" our thyroid from the particles of radioactive iodine. These are anyway less concentrated than in Japan because the half-life of iodine-131 is short (8 days), that is to say that it takes eight days for iodine 131 to lose half of its activity (and it took 13 -4 0 days for the radioactive plume to travel from Japan to France). Is the radioactivity detected in France safe for health? Even if the announced concentrations are very low, it is always difficult to know the minimal toxic dose and to affirm from which concentration one does not really risk anything for one's health. This radioactive pollution comes to add to all those we already experience in everyday life: the pollution of urban air and indoor air, the active or passive inhalation of toxic products of tobacco, the chemical pollution omnipresent in the water, in the air and food ... Not to mention that we are subjected to a natural radioactivity and that in this magnificent spring weekend, we had better beware above all of the most enormous thermonuclear power station: the sun, whose UV radiation directly threatens our skin. In short, in an already highly polluted environment, this superimposed micropollution could almost go unnoticed. But instead of taking the pollution individually by declaring for each of them that the rates are in the norms and that there is therefore no risk to health, the health authorities would be better off considering "the cocktail effect "Of these pollutions which must have a negative impact on our health. There is another question that is hidden: that of the accumulation of this radioactive pollution over time. The Fukushima nuclear plant has not finished spitting its poison and it is unclear how long the radioactive pollution will spread and accumulate in the environment. The longer it lasts, the more the risk will increase. Rain could also precipitate radioactive elements on the ground. For the French health authorities, as there seems to be no danger at the moment, it is not necessary to take iodine or food supplements containing it. Stable iodine intake before or during the passage of the plume is useless and discouraged because of undesirable effects. Let us not forget that it is the Japanese who are in the front line of this disaster disaster and who will suffer the heaviest health consequences.

It is still amazing to note that a nuclear accident at the other end of the world, has the potential to contaminate the entire planet in a few days ... External exposures Transient exposure, mainly gamma Most exposures to radioactivity are external that is to say that the source of radiation is external to the object or body irradiated. This is the case for natural radioactivity, cosmic radiation and radiation from rocks. This is also the case for medical exposures, mainly x-ray radiographs, and most accidental exposures. When it is natural or accidental, the external irradiation is generally global: it does not target a particular organ or tissue as it is the case of an internal irradiation where a radioactive element can be fixed preferentially on target organs such as bones or thyroid for example. External irradiation can however be targeted when it is intentional. This is the case of medical or industrial radiographs and therapies when the rays are aimed at a cancerous tumor. THE PROGRESSION OF AIR MASSES CONTAMINATES AMERICA AND EUROPE RADIOACTIVE ALERT ON JAPAN: Winds push back contaminated air masses to populated areas A mushroom, often associated with a nuclear explosion, is a distinctive character pyrocumulus mushrooms in the form of condensation clouds of water vapor and debris resulting from a very large explosion. The interior of an atomic mushroom: the air cooler is sucked into the toroidal rise fireball, which cools in the appearance of a familiar cloud. After the immediate detonation, the fireball itself begins to rise in the air, acting on the same principle as the air balloon. c.> A way of analyzing the motion, once the hot gas has cleared the ground sufficiently, like a "spherical cap bubble", which gives an agreement between the rate of rise and diameter observed. Then, the air is sucked upwards (similar to the rising of a chimney), producing strong drafts known as "afterwinds", while inside the head of the cloud of hot gases turn into a toroidal form.

When the detonation is weak enough, these afterwinds are outlined in dirt and debris from the ground to form the stem of the atomic mushroom. When the mass of hot gases is reached (equilibrium level), the cloud begins to propagate in the form of a characteristic mushroom.

The shape of the cloud is influenced by weather conditions and wind patterns. The distribution of the fallout is essentially a wind of the plume. However, if the cloud reaches the tropopause, it may extend, even against the wind direction, as the convection speed is higher than the ambient wind. The cloud shape in the tropopause is approximately circular and -IO spread. The initial color of some radioactive clouds may be red or reddish brown, due to the presence of nitrogen dioxide and nitric acid, formed from nitrogen, oxygen, and atmospheric moisture; ozone is also formed. It is estimated that each megatonne of yield produces about 5000 tons of nitrogen oxides. The reddish tint is then covered by the white color of the water vapor, the condensation in the fast-flowing air as the fireball cools, and the dark color of the smoke and debris drawn into the updraft. Ozone gives the breath of its characteristic corona discharge as smell. The droplets of condensed water vapor will gradually evaporate, leading to an apparent disappearance of the cloud. The radioactive particles, however, remain suspended in the air, and the now invisible cloud continues with its deposition of fallout on its trajectory. The cloud contains three major categories of material: the remains of cs fission products, the material acquired from the ground, and the water vapor. Most radiation is created by fission products. The degree of fallout production is therefore measured in kilotons of fission. Initially, the fireball contains a highly ionized plasma composed of atoms, fission products and atmospheric gases. As the plasma cools, the atoms react to form fine droplets and particles. Particles fuse for larger ones, and settle on the surface of other particles. Larger particles are generally derived from material sucked into the cloud. The concentration of the condensation products is the same for the small particles and for the deposition of surface layers of the larger particles. About 100 kg of small particles per kilotonne of yield are formed. A low-level detonation produces a dust cloud with a load of 100 tonnes per megatonne of output. A ground detonation produces clouds with about three times more dust. Approximately 200 tonnes per kilotonne for ground detonation, in contact with radioactivity. Submicron particle sizes range in size from micron to millimeter and above (ejecta from crater). Particle size and altitude determine how long they stay in the atmosphere, and larger particles are subject to dry precipitation. The smaller particles can also be trapped by precipitation, either condensation of moisture in the cloud itself or by the reunion of fungi with a cloud of rain; rainfall fallout is known as rainout. The particles of the airspeakers are smaller than 10-25 micrometers, usually in the submicron range. They are composed mainly of iron oxides, with a smaller proportion of aluminum oxide and uranium and plutonium oxides. Particles larger than 2.1 micrometers are very spherical. G Radioactivity is evenly distributed in particle volume Two types of particles are present; spherical, formed by vaporization-complete condensation or at least melting of soil particles, with a uniformly distributed activity in the volume (or with a volume of 10-30% of the basic inactive for the largest particles of 0.5 at 2 between mm), and irregular shaped particles formed on the edges of the fireball by the melting of the soil particles, with an activity deposited in a thin surface layer. The most radioactive particles are deposited by fallout in the first minutes and for a few hours. Small particles are transported to higher altitudes and descend more slowly. The smallest particles can reach the stratosphere and remain there for weeks, months or even years and reach the entire hemisphere by atmospheric currents. The high risk, in the short term, are localized fallout and deposited mainly downstream of the site of the explosion, in a cigar-shaped area. ts The condensation of water droplets in the cloud of the fungus depends on the amount of condensation nuclei. Too many condensation nuclei effectively inhibit condensation, water vapor. The primary radiation risk of fallout is gamma radiation from short-lived radioisotopes, which accounts for most of the activity. lo The radiation of the most significant sources are the fission products of the primary fission stage. The radioactivity of the particles decreases with time, with different isotopes at different time slots. Radioactive particles can be transported over considerable distances, depending on the wind. Our invention proposes to recover a maximum, and to store these particles in removable reservoirs of selective confinement, before their atmospheric journey extends over the entire planet. Their recovery will store them in a safe place, waiting for their neutralization. The Atmosphere Shield tio Air layers in the atmosphere provide protection against cosmic radiation that decreases with altitude and depends on the route followed. For commercial aircraft flying at 10 km altitude, the received dose varies from 0.005 mSv to 0.007 mSv depending on whether the route followed by the aircraft does not pass or passes through the poles.

At 18 km altitude the dose is approximately doubled. For an astronaut inhabiting a space station at 400 km altitude, the dose rate reaches 0.040 mSv per hour, so that two and a half days in orbit are sufficient for him to be exposed to the annual dose of natural radioactivity on the ground ( 2.4 mSv) (Source L. of Saint-Georges).

For the record, and a better "all-public understanding". The shortest way from New York to Hong Kong is through the North Pole. In March 2001, two US airlines inaugurated a transpolar route linking these two cities. A Chinese company had to follow. Crews and passengers on these polar routes are exposed to additional radiation, the US press echoed concerns expressed by scientists and unions of pilots, stewards and flight attendants . The importance of the poles is that the Earth is a big magnet. The magnetic field around it deflects part of the cosmic rays that bombard it. This magnetic shield adds to the layers of the atmosphere to protect radiation except for the two defects of its armor: the North and South poles. The traveler traveling on a polar road from New York to Hong Kong receives a dose of 0.100 millisievert (mSv), which is three times greater than the dose of a passenger on a Los Angeles Tokyo flight. only a little shorter. Radiation comes mainly from the Sun located in the suburbs to cosmic Earth. The doses received therefore depend on the solar activity following an 11-year cycle. The Sun experiences periods of eruption, which like earthquakes are classified according to their magnitude. Avoid flying over the pole during storms of high magnitudes. An airplane that allegedly took such a route on the day of the highest recorded eruption would have exposed its passengers to ten times the 0.100 mSv of a regular flight. The airlines operating these routes, which are accused of not informing their passengers of the dose supplements, take precautions and change their course in the event of a solar storm. The American Space Center (www.sec.noaa.gov) continuously monitors the activity of the 3rd Sun. It provides a summary of the upcoming week, predicts activity for the next 24 hours and sends out warning bulletins in case of a strong eruption. Any traveler has even free access, through the Internet, to a program allowing him to calculate the millisieverts received from one airport to another. The calculation does not take into account solar flares, the influence of which can be neglected outside the polar routes Sievert: biological dose unit The sievert or Sv is the unit used to measure the most significant biological doses for a given species. to be alive: effective dose, equivalent dose, committed dose .... The sievert constituting a unit is quite large, the 2 doses are generally expressed in thousandths of sievert (millisievert or mSv) In Europe, the effective annual dose at which the population is exposed is an average of 4 mSv per person The sievert replaced an old unit, the rem: 1 Sv = 100 rem).

Radioactivity and various applications Because of the fears it inspires, radioactivity is considered in our collective unconscious as hostile to the environment. Yet, well controlled, it helps to improve it through valuable controls.

An example is the monitoring of air quality and the dust content of mill discharges. To measure the degree of dust resulting from these discharges, the air is filtered permanently on a tape passing between a radioactive source and a detector. The intensity of the radiation received by the detector is a function of the dust level of the filter, which allows to determine this rate and take the necessary measures if the degree of dust is too strong. Radioactive gauges play a similar watchdog role in the coal industry, which still accounts for more than half of global electricity production. Certain neutron emitting gages (usually americium-241 and beryllium) measure and control moisture in coal and coke. Others, which emit gamma rays are used to ensure the composition of ashes and flue gases coming out of the chimneys. It is important to limit the amount of sulphides and nitrides present in these gases and ashes, because of the negative role played by its contaminants in acid rain. Radioactive sources are used as diagnostic tools in refining operations, which form an important part of the petroleum industry. Since it is difficult to introduce and maintain probes inside distillery towers because of extreme conditions, gamma probes can be installed outside the towers and moved vertically to follow the flow. Inside the liquid levels, record the ingredients composition at various heights and detect malfunctions. Plutonium is the most radiotoxic in spent fuel For some, plutonium is a highly radiotoxic and dangerous element whose only possible future is storage in the form of waste. For others, it is an element capable of providing a surplus of energy (the equivalent of 1 to 2 tons of oil per gram) and which must therefore be exploited to the maximum. Accidental exposures Hazards and sources of exposure in the event of a serious accident The main sources of exposure during a major release of radioactive material are cloud irradiation, inhalation of radioactivity, skin contamination and exposure to radiation. clothing, radioactive deposits on the ground and long-term ingestion of contaminated food and water. What are the characteristics of these sources? Radioactive cloud irradiation is an external irradiation usually by gamma radiation. When radioactive material is released following an explosion, the cloud formed from the initial plume is carried away by the winds. It is dangerous in the early days because of the predominance of highly radioactive elements, after which decay in time and dilution in the atmosphere diminish its importance. At Chernobyl, shortly after the explosion, xenon-133 was the most active element, followed by iodine-131. Xenon is a rare gas. It is not assimilable by living organisms, but disperse quickly. Although the air offers poor protection, the irradiation by the cloud is attenuated by the distance. In the case of gamma characteristics of 1 MeV of energy, the number 4 o of gamma not stopped by the air is divided by 1000 every 900 meters. Inhalation of radioactivity may be potentially more dangerous. It is due firstly to radioactive aerosols coming from the cloud during its passage, then later to dust resuspended. Contamination of the skin and clothing occurs especially during the first interventions and concerns people staying on highly contaminated sites. Like the inhalation of radioactivity, it occurs during the passage of the cloud and, later, by the resuspension of radioactive dust or the handling of contaminated material. The deposits of radioactive isotopes on the ground are the source of a gamma to external irradiation. Less intense than the cloud, it is closer and longer lasting. In the first few weeks, it is mainly due to short-lived radioactive isotopes such as iodine-131. At the scale of several years, it is cesium-137 that dominates. Contamination of the food chain The contamination of goat's milk in the mountains of Corsica in May 1986 is an example of the penetration of the food chain by radioactive elements, either by inhalation or as depicted on the vegetation. Some Mediterranean plants, such as thyme or dried fruits, contain more radioactive elements, because their water content is very low (less than 5% for 30 hazelnuts, against more than 80% for fresh fruits). Goats and ewes feed on these plants. Their milk, which was more mineralized than cow's milk, had levels of iodine-131 contamination of up to 15,000 becquerels per liter. However, this milk does not enter the diet of very young children who would be most sensitive to this contamination which decreases with a period of 8 days. Ingestion of contaminated food and water causes internal exposures. The contamination still comes mainly from iodine-131 in the first weeks and then cesium-137 when the weather has done its work. These two isotopes, absorbed by plants, enter the food chain. it 0 Screen effect of the atmosphere for a distant cloud What protection does the atmosphere offer against the gamma rays of a radioactive cloud? The question arises only for gamma rays because they are the only ones able to irradiate at a distance during massive and uncontrolled releases of radioactive materials. The first protection is due to the purely geometrical effect of solid angle: the angle at which a target is seen decreases rapidly with distance. But the environment crossed is not emptiness. The atoms of the air absorb gammas. This non-existent screen effect on the scale of the meter and ten meters, is felt from a few hundred meters. Without this atmospheric shield, life could not have developed on Earth bombarded by cosmic radiation. Consider the case study of an intense source of gamma rays of 1 MeV circulating at 1000 m altitude. 45 The gammas of 1 MeV of energy are not the most representative in the event of an accident, but they are among the most penetrating: they have to travel 90 m of air so that their number decreases by half. Radioactivity bars at 1000 m The risk from the passage of a radioactive cloud is measured by the flux (number of gamma per second) passing through a target surface on the ground. The figure shows the ground flows resulting from several radioactive bars 1 km long located at 1000 m altitude. It can be seen that the flow on the ground of the bar A located directly above the target is 14 and 60 times greater than that of the bars offset by 1 kilometer. In general, the exposure is mainly due to radioactivity located vertically. If the cloud moves, there will be a peak of exposure to the passage of the vertical, which will be brief if the cloud is not extended. Let us consider for the source a reference activity of 1 PBq (1 PBq represents one thousand billion kilo becquerels or 27,000 curies) and assume for computational convenience that strong activity distributed uniformly along a 1-km bar. If we evaluate the risk by the flow of gamma through a target of 1 m2 on the ground, the calculation shows that this flow is maximum when the bar is vertical to the target: 3o 25,000 gammas per square meter. In the void this flow would be 2800 times more intense. The flow decreases very quickly as soon as the bar deviates from the vertical. If it moves, there will be a peak of exposure in line with the target. At what dose would a human guinea pig be exposed, which would remain under the cloud for a whole day and whose 80 kg would have completely absorbed 25,000 gammas of 1 MeV per second? The calculation + shows that the daily exposure would be 0.004 mSv, an equivalent risk for some experts to smoke a quarter of a cigarette. The becquerels are always impressive but misleading! The shield effect becomes even more effective beyond 1000. On the contrary, it disappears quickly when the radioactivity or the intense radioactive source are close to 4 o their target. In our example, the flux can be counted in millions of becquerels at t5 35- 17 at a distance of 500 m vertically. It becomes imperative to take shelter, a ceiling or wall of 30 cm of concrete having the absorbing power of one km of air. This is what the pilots of helicopters who tried to dump sea water on buildings from which a deadly gamma radiation emerges and which they could not approach safely, experienced in the Fukushima accident. These simplified calculations give an idea of the protections provided by the atmosphere through a few orders of magnitude. It should be remembered that the air thicknesses that provide good protection against gamma sources of very high activity are of the order of one kilometer and below this protection is degraded quickly. An exact calculation would take into account that the gammas are not absorbed in a single shot, but by Compton effect generally communicate some of the energy to a secondary gamma that goes in another direction. At a great distance, gammas that reach the target have lost much of their -15 energy. Having traveled a longer path than the direct line they are more likely to be absorbed en route. Moreover, the transmitting nuclei of the cloud do not belong to a single species. It is necessary to take into account the energy range of the gammas present. To stick to iodine-131 and cesium-237, the main elements of the Chernobyl cloud, the energies of the main gammas emitted are 364 keV for iodine and 662 MeV for cesium. They are more quickly absorbed than those of 1 MeV taken in the example. STORAGE OF COLLECTION TANKS: High-level transport 1.5 Current high-level transport The transport of high-activity material produced by nuclear reactors is by far the most important. The number of these transports in France is 450 per year for irradiated fuels, about fifty for plutonium oxide powder, and about ten for MOX fuels. This very strong activity requires transporting fuel elements in specially designed containers called "castles". In France, PWR assemblies are transported in castles each containing 12 assemblages of 500 kg, in dry air. 3s "The transport cask is a containment barrier such that the fuel element can be transported by road or train.These steel containers are very resistant.Their thick walls protect them from radiation and their impermeability prevents dissemination of radioactive material. 'Almost all spent fuel for reprocessing is transported by rail to the Valognes railway terminal and then by road to the La Hague factory. Japan, and distant countries such as Australia, which do not have a reprocessing facility, Japan ships its spent fuel to the La Hague and Sellafield factories in Britain. irradiated fuel is discharged The fuel elements are deposited in one of the pools of the reprocessing plant of La Hague where they will wait again several years before being retired. After reprocessing, the recovered plutonium is sent packaged in boxes to the MOX fuel fabrication plant. Transport of vitrified waste: French vitrified waste, currently stored at the La Hague plant, does not require transport. Those belonging to foreign countries are returned. These transports are few. Between 1995 and 2001, two land transports were organized to Germany in 1996 and 1997, as well as three to Belgium in 2000 and 200, others to Switzerland; six returns of vitrified residues to Japan occurred in 1995, 1997, 1998, 1999 and 2000 respectively. These transports slowed down during the following decade. Japan commissioned its own reprocessing plant in Rokkasho-Mura. Germany has planned to stop the reprocessing of fuel from its plants. In November 2010, the eleventh convoy of vitrified waste from the I. Hague to Gorleben in Lower Saxony, where they are stored, was held. This convoy nicknamed the "train of hell" or "Tchemobyl rolling" by the German antinuclear is in principle the penultimate. His convoys attracted a lot of media attention because of the virulent opposition of the environmental movements. 3 c. Transport safety A luxury of precautions to ensure safe transport. Nuclear material is very radioactive. How to avoid any risk of accident, to guarantee the maximum safety? To reach these objectives, the principles of "defense in 35" depth are used.The maximum safety is ensured by the robustness of the packagings, the reliability of the transports, and also the prevention of accidents.The radioactivity of the spent fuel imposes transport it in specially designed containers called "castles." Their thick walls protect against radiation and their impermeability prevents the spread of radioactive material.The transport castle is a containment barrier that allows the transport of the fuel element or waste by road, train, or sea.

These heavy-duty steel containers over 100 tonnes have walls up to 30 cm The castles are designed to withstand fire, rocket fire and crushing that could occur during a truck or train accident who carry them. They must be tested for impact resistance (50 km / h), perforation, fire (800 ° C for 30 minutes) or 40 for immersion (under 200 m water). No transport of fuel is carried out by air, for obvious security reasons, and of congestion ... Mode of transport which will have nothing more to do with the Patent (Removable tanks of recovery of the radioactive cloud, with selective containment) equipping the 45 "air assets implemented Law of June 2006 Towards a deep storage center ... Voting in parliament of the 2006 law On the expiry of the 1991 law, a new law on waste radioactive was enacted on June 28, 2006. This law incorporates the three lines of research of the Bataille law.It establishes a schedule fixing in particular the choice of a site of the reversible repositories in deep geological layer. waste management and the dismantling of 2-5 installations Inset, Claude Birraux and Christian Bataille and Senator Henri Revol who actively participated in the development of the new A new law on radioactive waste, passed in June 2006, incorporates the main provisions of the Bataille law of 1991. 30 It extends it by specifying the dates at which the various solutions resulting from the research undertaken may enter into force. It provides for the continuation of research on the management of radioactive waste according to the three axes defined in 1991, separation-transmutation, storage and storage-conditioning. 75- The main decision concerns the creation of a reversible storage site for high-level long-lived waste in a layer of clay at 500 m depth.

The decision, recommended by the majority of experts, was expected. The approach is cautious and the legislator advances with counted steps. The choice of a storage site is planned for 2015, when all the elements will have been gathered to authorize the construction of such a center on the basis of studies made at the underground laboratory of Bure in Haute-Marne. The site will probably be built in an area of 200 km2, known as transposition, near the laboratory of Bure where research on the clay medium continues. Another important and new element compared to the 1991 law, the new law establishes a national radioactive waste management plan that includes national management not only for waste, but also for radioactive materials, whether or not they can be used. Three axes The Bataille law: three lines of complementary research Three lines of research The three lines of research defined by the Bataille law are intended to answer the still open questions on radioactive waste and to offer a range of means of management. They are complementary. The first explores the possibilities of sorting and destroying certain radioactive atoms, the second deals with the burial of high-level waste which will undoubtedly be inevitable. The third aims to improve the packaging of waste and to allow long storage. Axis 1: Separation and transmutation Separation research is concerned with methods for sorting 2.5 nuclear waste. We would go further than the sorting practiced today on an industrial scale and which is limited to separating uranium and plutonium from fission products and minor actinides. For example, we will try to separate a fission product such as cesium to separate it. But the separation is especially interesting if it is followed by a transmutation. It would then be possible to remove radioelements such as minor actinides which represent less than one thousandth of the mass of spent fuel, but whose lifetimes are very long. In order to transmute the actinides into short-lived radioactive products, or even into stable elements, nuclear reactions are required and the reaction is carried out in a reactor. With what reactors can we achieve a transmutation that has a satisfactory performance? Axis 2: deep storage Can the ultimate waste, which we do not know how to exploit at present, be buried without dangers in depth? In what types of soil is this storage possible? How to ensure the durability of such storage over long periods? How long should such storage be reversible? If by chance our descendants discovered a way to exploit this waste, or to make it disappear, can we ensure that they are able to extract it from the storage site? -t 0 Axis 3: Packaging and storage (Recoveries) There are already good packaging for multiple types of waste? Can we improve them, make them more resistant, adapt them to the type of radioactive atoms to immobilize? Used fuel and vitrified waste are already stored in facilities planned to last a few decades. Can these facilities be extended for periods of up to 300 years? Should these storages be on the surface or shallow? How to ensure over such a long period the monitoring and the good state of such installations which precede but do not replace a storage? o A calendar This calendar shows the options that would be opened in the future in the management of radioactive waste as a result of the proposed provisions. Whereas today the only option available for high-level waste is their storage, like that practiced at La Hague, after 2040, the entire range of options with geological storage, long-term storage and separation-transmutation. Long-term conditioning and storage (Axis 3): As the focus of Axis 3 of the 1991 Act, long-term surface conditioning and storage are two areas where significant progress has been made. So far volumes of high and intermediate level waste have been divided by 10 since 1992, by the vitrification of effluents, the compaction of technological waste and metal structures of fuels. Designed to complement current industrial storage with a 50-year lifespan, long-term surface or sub-surface storage is designed for 3 to 100 years of operation. Long-term storage could be put into operational service in France by 2015. I 2999329 22 Container Ax 3: Cases and containers ... Intermediate-level waste container Demonstrators of concrete containers that can be used for both uses, storage and storage for primary packages of medium-lived long-lived waste B (MAVL), were jointly studied by CEA and ANDRA. Container concrete is a special concrete, different from that proposed for storage or storage structures. The results on the cemented packages must be completed and new studies should be carried out in particular to take into account the case of the cracks. The National Evaluation Commission (CNE) considers in its final report that the packaging of high (HA) and medium activity (MAVL) primary packages is controlled and that the field has reached industrial maturity. These primary packages consist of vitrified waste and compacted waste produced at La Hague. The Commission considers that the conditioning of these two categories of waste is appropriate for their geological disposal, provided that additional containerization is included. Containerization means the action of packing primary packages and more generally other types of radioactive packages in boxes and containers adapted to erect an independent barrier, essential for the safety of both storage and a storage. Storage Container Demonstrators for Intermediate-Level B Waste (LLMA) primary packages, High-Level C waste (HLWL) and spent fuel assemblies were constructed. The study of their durability is done t; depending on the long-term storage projects proposed to house these containers. CEA teams have devised separate solutions for packages that do not emit heat and for packages that release it - spent fuel assemblies or vitrified waste packages. For thermal packages, the model study of their durability and their heat removal capacity is in progress. For long-lived intermediate-level waste (LLAV) packages, tests have shown that the radioelements present can not be recovered for transmutation and that these wastes are final (they represent only a few% of total activity). ). Since the primary packages do not release heat, it has been proposed to put them in durable concrete containers, which could be used for both storage and storage. Demonstrators of such containers, suitable for both uses, have been produced by CEA and ANDRA. Waste Fuels and Waste C 40 Container Project for Used Fuel Assemblies -10 Fuels assemblies, 4 m long mechanically vulnerable structures with a fragile matrix of irradiated uranium oxide pellets, require cases and containers for their storage and storage. The CEA has designed containers that can accommodate 7 UOX assemblies or 4 MOX assemblies that emit more heat. The individual case is made of waterproof welded stainless steel. It uses controlled industrial technologies. The Swedes, who will be among the first to bury their spent fuel, have chosen large copper containers for assemblies from their reactors. Copper was selected for its corrosion resistance. These containers, full, will weigh 25 tons. Finally, for high-level vitrified waste packages, the containers would be similar in design to that of spent fuel assemblies. For example, a CEA project is considering containers that can accommodate 6 CDS-V packages. Conditioning At the La Hague plant, solutions of minor fission products and actinides are calcined at about 400 ° C, then vitrified by mixing with glass frit in an oven at a temperature of about 1100 ° C. The molten glass is poured into a cylindrical (right) container of special steel. The lid is then laid and welded to the container. The cutaway model shows on the left the inside of a standard container of vitrified waste. The mass of the glass is about 400 kg, that of the radioactive products themselves being about 11 kg.

INDICATING HOW THE INVENTION IS SUCEPTIBLE OF INDUSTRIAL APPLICATION. This device will protect a technical innovation, that is to say a product or a process that provides a technical solution to a given technical problem. In this case, it will be the entire system of suction and recovery, with containment and storage of a radioactive atmospheric cloud, may result from a major radioactive leak, or a nuclear disaster like that of Fukushima in JAPAN. This process can also be used, during a volcanic eruption (ash clouds for example) or simply, during large fires, devastating. , 2999329 25 LEGEND 1 - Suction mouth with turbine protection grille (large detritus, waste, aggregates ...) 5 2 - Suction pump, or turbine 3 - Electronic purifier 4 - Compressor with filter for the compressed air 5 - Purge circuit with automatic valves 6 - Radioactive compressed air tank (minimum capacity of 5000L and test pressure of 16 10 bar 7 - Matrix tank for cylindrical container in special steel, Vitrification of radioactive waste (La Hague factory ) 8 - Container base (collection tank) for vertical ground storage

Claims (1)

CLAIMS1 - A nuclear cloud suction device arranged in the form of a collection tank, characterized in that it comprises: - a suction mouth with a protective grille of the turbine - a suction pump or turbine - an electronic purge chamber for purging condensates, - a compressor with filter for compressed air - a purge circuit with automatic valves - a radioactive compressed air tank with a minimum capacity of 5000L and resistant to pressure 16 bar - a condensate recovery tank - a base for vertical storage on the ground.