RU2667072C2 - Production of molybdenum-99 with use of electron beams - Google Patents

Abstract

FIELD: nuclear physics, nuclear technology.SUBSTANCE: invention relates to methods, systems and apparatus for the production of molybdenum-99. Device is intended forMo production from a variety ofMo targets by photonuclear reaction onMo targets and can be used in medical diagnostic studies. Device comprises a linear electron accelerator, a water-cooled converter for producing a high-energy brake photon flux, a water-cooled target assembly for mounting thereinMo target holder, shielding components for protecting the water-cooled target assembly. Apparatus further comprises an integrated target transfer assembly with a component for remotely controlled loading and transport of target holders to the target transfer component.EFFECT: technical result - ensured production ofMo fromMo by irradiation with high-energy electrons using linear accelerators.13 cl, 26 dwg

Description

FIELD OF THE INVENTION

The present invention relates to methods, systems and apparatus for the production of molybdenum-99. More specifically, the present invention relates to the production of molybdenum-99 from targets containing molybdenum-100, using powerful linear electron accelerators.

State of the art

Technetium-99m (hereinafter - ^99m Tc) is one of the most widely used radioactive indicators in the diagnostic procedures of nuclear medicine. ^99m Tc is used daily for detecting various forms of cancer, for heart electrocardiograms taken during exercise with exercise, for determining bone density, for creating images of selected organs and for other diagnostic studies. ^99m Tc emits easily detectable 140 keV gamma radiation and has a half-life of approximately 6 hours only, thereby limiting the effects of radiation on patients. Due to the very short half-life, nuclear-equipped medical centers receive ^99m Tc as a result of the atomic decay of the parent molybdenum-99 isotope (hereinafter ⁹⁹ Mo) using ^99m Tc generators. ⁹⁹ Mo has a relatively long half-life of 66 hours, which makes it possible to transport this isotope around the world to medical centers from nuclear reactor facilities in which large-scale production of ⁹⁹ Mo is produced by fission of highly enriched uranium 235. The problem of nuclear production of ⁹⁹ Mo is The fact that deliveries of this material all over the world come from five nuclear reactors, which were built in the 1960s and are currently nearing the end of their service life. Nearly two-thirds of the global supply of ⁹⁹ Mo is currently made from two reactors: (1) the national research universal reactor, located at the Chalk River laboratory in Ontario, Canada, and (2) the Petten nuclear reactor in the Netherlands. In the past few years, there has been a significant ⁹⁹ Mo deficit due to planned or unplanned shutdowns at both main reactors producing this material. As a result, there was a serious shortage of material for medical equipment within a few weeks of shutting down the reactor, which led to a significant decrease in material for medical diagnostic testing, and also to an increase in the production load on the remaining nuclear reactors. Although both of the reactors currently in an active state again, there is much uncertainty in the world in terms of reliability of long-term supply Mo ^99.

SUMMARY OF THE INVENTION

Examples of embodiments of the present invention relate to a device, systems and processes for the production of molybdenum-99 ( ⁹⁹ Mo) from molybdenum-100 ( ¹⁰⁰ Mo) by irradiation with high energy electrons using linear accelerators. Some embodiments of the invention relate to systems for implementing the methods of the present invention. Some embodiments of the invention relate to a device comprising the systems of the present invention.

Brief Description of the Drawings

The present invention will be described with reference to the following drawings, in which:

FIG. 1 is a perspective view illustrating an embodiment of the system of the present invention shown with a protective shielding installed.

FIG. 2 is a perspective view of an embodiment of the system shown in FIG. 1, in which the protective shielding has been removed.

FIG. 3 is a side view of an embodiment of the system shown in FIG. 2, with a remote screening guard with a linear accelerator system.

FIG. 4 is a top view of a variant of the system shown in FIG. 3.

FIG. 5 is an end view of FIG. 3, shown from the side of the linear accelerator.

FIG. 6 (A) is a perspective view showing a target assembly of an embodiment of the system of FIG. 2 partially exempted from the protective shielding, and FIG. 6 (B) is a perspective view showing an open target assembly.

FIG. 7 is a side view of the target displacement site (perpendicular to the electron beam generated by the linear accelerator).

FIG. 8 is a front view of a target displacement assembly showing an inlet for a beam of brake photons generated from an electron beam of a linear accelerator.

FIG. 9 is a sectional side view of the target displacement assembly shown in FIG. 8.

FIG. 10 is a top sectional view of the target displacement assembly shown in FIG. 8, at the junction of the cooling rack component and the casing for the beam channel.

FIG. 11 is a top sectional view of the target displacement assembly shown in FIG. 8, on which an energy converter and a target holder are mounted in the beam channel.

FIG. 12 is a schematic illustration of the conversion of a high energy electron beam to a stream of bremsstrahlung photons for irradiating a plurality of ¹⁰⁰ Mo targets.

FIG. 13 is an enlarged sectional side view of FIG. 9, showing mounted energy converter and target holder.

FIG. 14 is an enlarged cross-sectional plan view of FIG. 11, showing mounted energy converter and target holder.

FIG. 15 (A) is a perspective view of an embodiment of a target holder; FIG. 15 (B) is a sectional side view of a target holder.

FIG. 16 (A) is a top perspective view of an embodiment of a cooling tube, FIG. 16 (B) is a perspective view from below of a cooling tube, and FIG. 16 (C) is a sectional side view of a cooling tube.

FIG. 17 (A) and 17 (B) show another embodiment of the cooling tube of the invention installed in the target assembly of FIG. 9.

FIG. 18 (A) and 18 (B) show the cooling tube of FIG. 17 locked in place at the target site.

FIG. 19 is a perspective view of an embodiment of a device for moving molybdenum with a remote control mounted on the protective shielding of the section of the target assembly of the embodiment of the system shown in FIG. one.

FIG. 20 is a perspective view of an embodiment of a base of a frame support for an embodiment of a remote control molybdenum moving device shown in FIG. 19.

FIG. 21 is a perspective view of an embodiment of a pallet of a loading and unloading device that cooperates with a frame support base shown in FIG. twenty.

FIG. 22 is a perspective view of an embodiment of a shielding container that can be mounted on a pallet of the loading and unloading device shown in FIG. 21.

FIG. 23 is another perspective view of an embodiment of the remote control molybdenum transfer device shown in FIG. 19.

FIG. 24 (A) is a perspective view of an embodiment of a gripping component from the remote controlled molybdenum transfer device shown in FIG. 19 and 23, shown in the meshing position with the crane hook, and FIG. 24 (B) is a cross-sectional side view of an embodiment of a gripping component when it engages with a molybdenum target holder.

FIG. 25 is a perspective view of an embodiment of a tipping rack for connecting and disconnecting a device for moving molybdenum with the remote controls shown in FIG. 19 and 23, the tipping rack is configured to receive and hold the cooling tube assembly.

FIG. 26 is a horizontal sectional view of the tipping rack shown in FIG. 25.

The implementation of the invention

Embodiments of the invention relate to systems, apparatus, and processes for producing ⁹⁹ Mo from ¹⁰⁰ Mo targets using high energy electron beams generated by a linear accelerator.

A linear particle accelerator (often called a linac) is a particle accelerator that significantly increases the speed of charged subatomic particles by exposing charged particles to a sequence of vibrational electric potentials along a linear beam channel. The generation of electron beams by a charged particle accelerator as a whole requires the use of the following elements: (1) an electron generating source, usually a cathode, (2) a high voltage source for the initial injection of electrons into (3) a vacuum hollow tube, the length of which will depend on the required electron energy beam, (4) a plurality of electrically isolated cylindrical electrodes located along the length of the tube, (5) a radio frequency energy source for supplying each of the cylindrical electrodes, i.e. one source of energy per electrode, (6) a set of quadrupole magnets surrounding the evacuated tube for focusing the electron beam, (7) the corresponding target, and (8) a cooling system for cooling the target during electron beam irradiation. Linear accelerators are routinely used for various purposes, such as the generation of X-rays, as well as the generation of high-energy electron beams for radiation therapy of patients with cancer.

Linear accelerators are also widely used as injectors For high-energy accelerators such as synchrotrons, and can also be used directly to obtain the highest possible kinetic energy for light particles, so that they can be used in particle physics through bremsstrahlung. Bremsstrahlung is electromagnetic radiation generated by the deceleration of a charged particle when it is deflected by another charged particle, usually an electron, under the influence of an atomic nucleus. A moving electron loses kinetic energy, which is converted into a photon due to energy conversion. The bremsstrahlung has a continuous spectrum, which becomes more intense, and the peak in the spectrum's intensity shifts toward higher frequencies as the energy change of accelerated electrons increases.

However, it seemed to those skilled in the art that the use of electron linear accelerators to generate high-energy photons via bremsstrahlung for the further production of radioisotopes through a photonuclear reaction is an inefficient way to produce radioisotopes, since the electromagnetic interactions of electrons with nuclei are usually much smaller than strong interactions with protons as falling particles. However, we determined that ¹⁰⁰ Mo has a wide “giant dipole resonance” (GDR) for photoneutron reactions with photon energies of about 15 MeV, which leads to a significant increase in the reaction cross section between ¹⁰⁰ Mo and ⁹⁹ Mo. In addition, the radiation length of a high-energy photon, in the range from 10 to 30 MeV, in ¹⁰⁰ Mo is about 10 mm, which is significantly longer than this length for a proton of the same energy. Consequently, the effective thickness of the target is also much larger for photoneutron reactions compared to proton reactions. The reduced number of reaction channels associated with electron beams generated by linear accelerators limits the production of unwanted isotopes. For comparison, the use of proton beams for the direct production of ⁹⁹ Tc from ¹⁰⁰ Mo often leads to the generation of other Tc isotopes from other stable Mo isotopes, which can be in enriched ¹⁰⁰ Mo targets. Medical uses impose strict restrictions on the amounts of other radioisotopes that may be present along with ⁹⁹ Tc, so it seems that the production of ⁹⁹ Tc from ¹⁰⁰ Mo using an electron generated by a linear accelerator will be preferable, since the risk of obtaining other Tc isotopes is much lower. In addition, apparently, as a result of photoneutron reactions with other molybdenum isotopes located in ¹⁰⁰ Mo targets, stable Mo is usually obtained.

Accordingly, an embodiment of the present invention relates to a device with a high energy electron beam accelerator for producing ⁹⁹ Mo from a plurality of ¹⁰⁰ Mo targets through a photonuclear reaction on ¹⁰⁰ Mo targets. The device as a whole comprises at least (1) a linear electron accelerator capable of producing electron beams of at least 5 kW, about 10 kW, about 15 kW, about 20 kW, about 25 kW, about 30 kW, about 35 kW, about 45 kW, about 60 kW, about 75 kW, about 100 kW, (2) a water-cooled converter to produce a high flux of high-energy brake photons of at least 20 MeV from an electron beam generated by a linear accelerator, a brake photon flux with an energy of about 25 MeV, about 30 MeV, about 35 MeV, about 40 MeV, about 45 MeV, (3) a water-cooled target assembly for installing a target holder in it containing a large number of targets of ¹⁰⁰ Mo, as well as for accurately positioning and aligning the target holder so that the target crosses the radiation beam of a high-energy brake photon flux generated by a water-to-water converter cooling, and (4) a plurality of shielding components for enclosing the target water-cooled assembly in order to retain gamma radiation and / or neutron radiation within the target assembly and to prevent radiation leakage device limits. Depending on how the component is shielded and its location inside the installation, shielding may contain one or more of the following materials: lead, steel, copper and polyethylene. The device further comprises (5) an integrated target displacement unit with a component for remotely controlled loading and transporting a plurality of target holders to the target displacement component, wherein each of the target holders is loaded with a plurality of ¹⁰⁰ Mo targets. A separate loaded target holder can be moved from a remotely controlled loading / moving component to a target moving component contained within a water-cooled target assembly. The target holder is transported using the component moving the target to a position that intersects with the bremsstrahlung photons. The base of the target displacement component comes into contact with the centering and aligning component of the target, which accurately positions and aligns the loaded target holder for maximum intersection with the brake photons. The integrated target displacement unit is additionally configured for remotely controlling the removal of the irradiated target holder from the target displacement component and moving it into the lead shielded hot chamber (for working with highly active substances) to separate and recover ⁹⁹ Tc decaying from ⁹⁹ Mo associated with irradiated ¹⁰⁰ Mo targets. Alternatively, irradiated ¹⁰⁰ Mo targets can be transported into a lead-shielded shipping container to move it to a hot chamber located elsewhere.

Obviously, the maximum achievable yield of ⁹⁹ Mo depends on the energy that can be safely transferred to the ¹⁰⁰ Mo target, as well as on the probability of the reaction of “giant dipole resonance” photons interacting with the target nuclei. The amount of energy that can be safely transferred to a ¹⁰⁰ Mo target depends on the heat capacity of the target assembly. If it is possible to quickly transfer large amounts of heat from ¹⁰⁰ Mo targets, then it will be possible to transfer more energy to the ¹⁰⁰ Mo targets before they melt. Water is a desirable cooler because it helps to dissipate a large amount of heat and is also economical. Unfortunately, when an electron beam passes through cooling water inside a bremsstrahlung converter, the energy associated with the electron beam causes radiolysis of water. Radiolysis of water, among other phenomena, leads to the formation of hydrogen gas, which creates a danger of explosion, as well as hydrogen peroxide, which is corrosive to molybdenum and therefore can significantly reduce the potentially achievable outputs of ⁹⁹ Mo from ¹⁰⁰ Mo targets. The energy associated with inhibitory photons passing through the cooling water in the water-cooled assembly of the target containing the ¹⁰⁰ Mo target also causes the formation of hydrogen peroxide from the water, but much less hydrogen gas.

Accordingly, another embodiment of the invention relates to separate cooling systems, which are required for a water-cooled energy converter and for a water-cooled target assembly, so that heat dissipation from two components can be separated and production of ⁹⁹ Mo from ¹⁰⁰ Mo targets can be maximized.

It is within the scope of the present invention to include in a first water cooling system for a bremsstrahlung converter, apparatus, or equipment, or device for combining hydrogen gas with oxygen to form water in recirculating water. An additional option is to use gaseous coolers to cool the bremsstrahlung converter or, alternatively, add water cooling to the bremsstrahlung converter.

Also included in the scope of the present invention is the inclusion in the second water cooling system for a water-cooled target assembly of one or more buffers to reduce the corrosive effects of hydrogen peroxide on molybdenum, consumable metals and additional circulation of a gaseous cooler. Suitable buffers are, for example, lithium hydroxide, ammonium hydroxide, and the like. Suitable consumable metals are, for example, copper, titanium, stainless steel, and the like.

Embodiment 10 with a powerful linear electron beam accelerator for producing ⁹⁹ Mo from a plurality of targets of ¹⁰⁰ Mo is shown in FIG. 1-5; it contains an electronic linear accelerator of 20 by 35 MeV and 40 kW, manufactured by Mevex Corp. (Ottawa, ON, CA), section 25 of the collimator for narrowing the electron beam generated by the linear accelerator 20, and section 30 of the target assembly containing the camera 42 irradiation of the target (Fig. 6-11), the node 32 of the cooling rack, the supply of 34 coolant and a vacuum installation 36 connected to the target irradiation chamber 42 through a vacuum tube 37. The components 20, 25, 30 included in the installation 10 with a linear electron beam accelerator are shielded with a protective shielding 15, so as to retain and limit gamma radiation and / or neutron and emission. An electronic linear accelerator of 20 by 35 MeV and 40 kW contains three axial coupled sections with a standing wave of 1.2 m frequency band (S-band), three modulators with high-performance klystrons with a peak power of 5 MW and a 60 kV thermionic gun. The linear accelerator 20 is mounted on a supporting structure 22, which is equipped with rollers 23, allowing the linear accelerator 20 to be disconnected from the collimator section 25 to provide access to the components of the converter section 25 and their maintenance. Section 25 of the collimator comprises a water-cooled tapering copper tube connected to the first water cooling system, the copper tapering tube having a beryllium window for narrowing the electron beam generated by the linear accelerator 20 to a diameter of from about 0.075 cm to about 0.40 cm, from about 0, 10 cm to about 0.35 cm, from about 0.15 cm to about 0.30 cm, from about 0.20 cm to about 0.25 cm.

Section 30 of the target assembly includes a support plate 39 for the support element 38, on which the target irradiation chamber 42 with the inlet tube 40 is mounted for tight connection with the electron beam supply tube 28 (Fig. 6 (A) and 6 (B)). The cooling column 32 is hermetically connected to the target irradiation chamber 42 directly above the irradiation chamber, in which the target holder is mounted during the irradiation process. The vacuum tube 37 and the cooling unit 34 of the transducer portion are hermetically mounted on the side of the target irradiation chamber 40 (Fig. 6 (A) and 6 (B)). The cooling rack 32 includes a cooler tube casing 44, which is hermetically connected at the remote end by a plurality of nuts 45a to the cooler tube cap assembly 45. The cooler tube cap assembly in this embodiment has rods 48 for remotely controlled engagement with a crane (not shown) for lifting and separating the cooling rack 32 from the target irradiation chamber 42 (Fig. 7-9). The cooling water supply tube 100 (Fig. 16 (A) -16 (C)) is located inside the casing 44 of the cooler tube and is connected to the second water cooling system through a water supply tube 46, which is hermetically connected to the node 45 of the cooler tube cap.

The cooling water supply pipe 100 (Fig. 16 (A) -16 (C)) includes an upper sleeve assembly 101 at the proximal end, a cooler supply tube 103, a plurality of guide ribs 104 at the proximal end, and a cooling tube housing holder 105 for detachable connection with the holder 80 targets. The upper sleeve assembly 101 is provided with a hook 102 for remotely installing, by means of an overhead crane (not shown), a cooling water supply pipe 100 to and from a cooler tube casing 44. External shielding 106 is provided around the cooler supply tube 103 to position the cooler supply tube 103 inside the cooler tube casing 44 and provide shielding from the flow of brake photons that can penetrate the cooler tube casing 44. The outer surface of the outer shielding 106 has channels that allow the flow of cooling water to flow through them. The cooler supply tube 103 has an inner upper shield 107 and an inner lower shield 108 to provide protection against the flow of brake photons that may penetrate the cooler feed tube 103. The cooling water is supplied from the second cooling water supply system through the water inlet pipe 46 to the proximal end of the cooler supply pipe 103 through an inlet (not shown) in the upper sleeve assembly 101 and discharged from the cooler supply pipe 103 at a remote end through the holder of the cooling tube body 105, and then moves back to the upper sleeve assembly 101 into the space between the outside of the cooler supply tube 103 and the inside of the cooler tube casing 44, and then enters the cooling water supply tube 100 through the openings 109, BUT in the node 10 of the upper sleeve. The cooler supply tube 103 has a plurality of ribs 104 around an outer diameter, close to the holder of the cooling tube tube housing 105, and functions as a guide for remotely installing the cooling water supply tube 100 into the casing 44 of the cooler tube and removing it using a bridge crane (not shown). The cooler tube casing 44 has a node 47 for aligning the cooler tube in order to ensure accurate alignment of the cooling water supply tube 100 in the cooler tube casing 44. The cooling water supplied to the target irradiation chamber 42 and passed through it with the help of the cooling stand 32, then returns to the second water cooling system.

The target irradiation chamber 42 has an inner chamber 55, in which a section of the bremsstrahlung converter 70 is placed near the electron beam inlet tube 40 (Figs. 11, 13, 14). The bremsstrahlung converter section 70 is accessible through the cooling section 34 of the converter section, which is hermetically connected to the side of the target irradiation chamber 42. The cooling section 34 of the converter section comprises a cooling water tube 50 receiving a cooling water stream from the first water cooling system for circulating water in, around and from the brake radiation converter section 70. The cooling water tube 50 is placed inside the casing 35. The vacuum tube 37 is connected to the vacuum unit 36, while it is also hermetically connected to the side of the target irradiation chamber 42, and also communicates with the inner chamber 55. After the installation 10 with a powerful linear electron beam accelerator assembled, the integrity of the beryllium window of beryllium oxide and its sealing in the collimator section 25 is determined, as well as the integrity of the silicon window (alternatively, the diamond window) placed between the inlet pipe 40 and the conversion section 70 ovatelya bremsstrahlung by evacuating chamber 55 by the vacuum apparatus 36 through vacuum tube 37.

Section 70 of the bremsstrahlung converter comprises four thin tantalum plates 26 in series (FIG. 12), which are placed at an angle of 90 ° to the electron beam 21 (FIG. 12) generated by the linear accelerator 20. However, it should be noted that the quantity and / or thickness Tantalum plates can be varied in order to optimize and maximize the generation of photons generated by the electron beam. If desired, plates containing another metal with a high density, for example, tungsten and tungsten alloys containing copper or silver, can be used. Tantalum plates 26, when bombarded by a high-energy electron beam, convert the incident electrons into a flux of 27 photons of bremsstrahlung (Fig. 12), which is delivered directly to the target holder 80, containing many disks 85 of the targets of ¹⁰⁰ Mo (Figs. 13, 14). It should be noted that the transducer may comprise more than four tantalum plates, or alternatively, less than four tantalum plates. For example, one tantalum plate, two tantalum plates, three tantalum plates, five tantalum plates or more. Alternatively, the plates may contain tungsten, or copper, or cobalt, or iron, or nickel, or palladium, or rhodium, or silver, or zinc, and / or their alloys. The design and configuration of the converter section 70 is designed to dissipate a large amount of heat that is carried by a high-energy electron beam so as to minimize heat transfer to the photon beam and to reduce the heat load transmitted to the ¹⁰⁰ Mo targets during irradiation. In addition, the tantalum plates 26 and the target holder 80 containing a plurality of disks 85 of the targets of ¹⁰⁰ Mo are cooled during the irradiation process by constantly circulating: (1) cooling water through the tantalum plates 26 using the first water cooling system, and (2) cooling water through disks of 85 targets of ¹⁰⁰ Mo, using a second water cooling system.

Another embodiment of the present invention relates to target holders for receiving and containing a plurality of disks 85 of targets of ¹⁰⁰ Mo. An embodiment of a target holder 80 containing a consecutive group of eighteen disks 85 of targets ¹⁰⁰ Mo is shown in FIG. 15 (A) and 15 (B). At the ends of the target holder 80, there are slots for engaging with the holder 105 of the cooling tube body at the remote end of the cooler supply tube 103. It should be noted that suitable target holders for irradiating ¹⁰⁰ Mo targets with the installation option 10 with a powerful linear electron beam accelerator of the present invention can accommodate successive groups of any number of ¹⁰⁰ Mo target disks in the range from about 4 to about 30, from about 8 to about 25, from about 12 to about 20, from about 16 to about 18. Suitable ¹⁰⁰ Mo target discs can be prepared by pressing powders or granules of ¹⁰⁰ Mo grade into discs and then formed discs are sintered. Alternatively, separate powders and / or pellets ¹⁰⁰ Mo reconstructed from previously irradiated targets ¹⁰⁰ Mo can be pressed into discs and then sintered. Alternatively, after powders or granules of ¹⁰⁰ Mo are formed into disks, materials with ¹⁰⁰ Mo are subjected to arc melting or electron beam melting or other similar processing methods for compaction. Sintering should be carried out in an inert atmosphere at a temperature in the range from about 1200 ° C to about 2000 ° C, from about 1500 ° C to about 2000 ° C, from about 1300 ° C to about 1900 ° C, from about 1400 ° C to about 1800 ° C, from about 1400 ° C to about 1700 ° C in the time range of 2-7 hours, 2-6 hours, 4-5 hours, 2-10 hours in an atmosphere without oxygen provided by an inert gas such as argon. Alternatively, the sintering process may be performed in a vacuum. Suitable sizes for ¹⁰⁰ Mo target discs can be from about 8 mm to about 20 mm, from about 10 mm to about 18 mm, from about 12 mm to about 15 mm, with a density in the range of from about 4.0 g / cm ³ to about 12.5 g / cm ³ , from about 6.0 g / cm ³ to about 10.0 g / cm ³ , about 8.2 g / cm ³ . The end elements 81 of the target holder 80 have two or more slots 82 for engagement with the holder 105 of the cooling water supply tube 103, or alternatively, the cooling water supply tube 154 (FIG. 18 (A), 18 (B)).

In FIG. 9 is a vertical cross-sectional view of an embodiment of a target holder 80 containing a sequential group of 18 target disks ¹⁰⁰ Mo mounted securely in a target irradiation chamber 42 for irradiation with a bremsstrahlung photon generated by a bremsstrahlung section 70. FIG. 13 and 14 are on a large scale, respectively, a side view and a top view of the target holder 80, fixed in place by an element 105 of the body of the holder of the cooling water supply pipe 100 (Fig. 16 (A) -16 (C)) and positioned for irradiation with a brake flow photons.

FIG. 17 and 18 show another embodiment of the cooling water supply tube assembly 153 installed in the casing 144 of the cooling water tube. The cooling water supply tube assembly 153 generally comprises a cooling water pipe 154 having a plurality of guide ribs 155 for cooling water pipes around a proximal end, a cooling water pipe housing holder 156 at a distal end (FIG. 17 (A)), and a retaining ring 162 near the proximal end (FIG. 17 (B)). The cooling water supply tube 154 has an outer shielding 157, an inner upper shielding 158 (FIG. 17 (B)), and an inner lower shielding (not shown). The upper end of the casing 144 of the coolant pipe has a node 141 of the cap of the pipe of the coolant containing the housing 142 of the cap of the pipe of the coolant, which engages as a single part with the upper end of the casing 144 of the pipe of the coolant (Fig. 17 and 18). The housing 142 of the cap of the coolant tube has as an integral part a shoulder 143 for fitting the retaining ring 162 of the coolant tube (Fig. 18 (A) and 18 (B)). The coolant pipe cap assembly 141 also includes a flange 147 located between the coolant pipe cap body 142 and an annular protrusion 145 that is fully engaged with the upper part of the coolant pipe cap body 142 / The annular protrusion 145 of the coolant pipe cap has a plurality of vertical channels 146 in a circle around the inner diameter, with each vertical channel 146 having an adjacent horizontal lateral channel 146a (FIG. 17 (A)). In addition, there is a cap 151 of the coolant pipe for tightly connecting to the annular protrusion 145 of the cap of the coolant pipe after the cooling water supply unit 153 is installed in the casing 144 of the coolant pipe (Fig. 18 (A) and 18 (B) ) The coolant tube cap 151 has a plurality of outwardly projecting protrusions 151a spaced around a side wall for sliding engagement with the vertical channels 146 and horizontal side channels 146a of the annular protrusion 145 of the coolant tube cap. The mounting loop 152 of the coolant tube cap is attached on top of the cover of the coolant tube 151 for releasably engaging with the crane hook 266, which is controlled by a remotely controlled operation of the molybdenum moving device (FIG. 19 (A), 19, 23).

Another embodiment of the present invention relates to a remotely controlled molybdenum transfer device for moving target holders loaded with a plurality of disks 85 targets ¹⁰⁰ Mo into a section of a target node for irradiating a high flux of high-energy brake photons, returning the irradiated target holders from the target node section, moving and sealing the irradiated target holders in a lead-shielded container, and then moving the lead-shielded container into the transport device To remove the equipment from the radiation of the linear accelerator. A remotely controlled molybdenum transfer device 200 is also used to insert and remove a cooling water supply tube assembly to / from a section of a target assembly.

A corresponding embodiment of the remotely controlled molybdenum transfer device 200 is shown in FIG. 19, 23. In general, it comprises a frame structure 230 on which a trolley assembly 240 is mounted “along the X axis” for remotely controlled movement in the horizontal plane of the trolley assembly 250 “along the Z axis”. The trolley assembly 250 along the “Z axis” moves the gripper assembly 256 (FIG. 24 (A), 24 (B)) in a vertical plane. The remotely controlled molybdenum transfer device 200 is mounted on the base 202 of the frame support (FIG. 20), which, in turn, is mounted on the protective shielding 15 (FIG. 19), completely covering the component 30 of the section of the target assembly of the exponential system 10 shown in FIG. 1. The frame structure 230 of the remotely controlled molybdenum manipulator 200 is attached to the base 202 of the support frame (Fig. 20), while it contains two main supporting elements in the form of, for example, finished rails 203 made of stainless steel with the cross section in the form of the inverse letter " T ”having a structure with mounting holes matching the bolt holes (not shown) of the structure for shielding the target chamber. T-rails 203 run parallel to the linear accelerator and are located on top of the protective shielding 15, they are screwed down into steel blocks (not shown) lying under the protective shielding 15 and completely covering the section 30 of the target site. Several transverse rungs 204 connect two T-shaped support rails 203 to support the structure. The end closest to the linear accelerator has a prefabricated building channel 206 that supports one end of the frame structure 230 and the stationary end of the pneumatic cylinder 209 of the pallet of the loading and unloading device. The mounting plates 208 for the other end of the frame structure 230 are located further along the supporting T-shaped rails 203. The guide rail 210 of the loading and unloading device is screwed to a base plate (not shown), which, in turn, is screwed across the supporting T-shaped rails 203. The guide the rail 210 of the loading and unloading device vertically supports and horizontally directs the linear movement of the pallet 212 of the loading and unloading device, perpendicular to the main supporting T-shaped rails 203. Long drops Sheet 220 also rests on several transverse crossbars 204. Dropper 220 is used to collect contaminated cooling water that may drip from the cooling tube assembly or flow chamber lid when manipulated (as will be described later). The dropper 220 is made of two parts to allow assembly around the opening 222, which gives access to the section of the cooling rack 32 of the target assembly 30 (shown in Figs. 4, 5). The articulation and opening around the opening 222 is blocked and sealed to minimize leakage. Each end of the dropper 220 has a drain at the bottom of the dropper, which is connected to the elbow with a cap (not shown). Temporarily drainage hoses can be attached to these elbows to collect waste water from decontamination fluids. The dropper 220 has four pins that serve as the mounting / collapsible position 219 for the tipping rack assembly (position 270 in FIG. 25) and the tipping support 221. In the context used here, the term “demountable” means that a component, such as a tipping rack assembly, can be temporarily secured in the installation position, and then can be released from it later and removed.

The pallet 212 of the loading and unloading device (Fig. 21) can, for example, be made in the form of a molded and welded stainless steel tray with approximate dimensions: 700 mm in length × 250 mm in width × 30 mm in depth. The pallet 212 of the loading and unloading device is equipped with (1) mounted support rollers with four support legs (not shown) for vertical support during movement, and (2) two support rollers (not shown) to support horizontal alignment during movement. The pallet 212 of the loading and unloading device reliably positions and transports in the transverse direction the base 292 of the shielding container on the vertical mounting fingers 214 of the cover 295 of the shielding container (Fig. 23) in the storage 216 and the cap 151 of the cooling tube (Fig. 18 (A), 18 ( B)) in the storage 281, at a location below the remotely controlled device 200 for moving molybdenum for further remote movement. The shielding container 290 is manually mounted on (and removed from) the pallet 212 of the loading and unloading device before and after the end of the remote movement operations. Two vertical mounting fingers 214 are used to align and stabilize the base 292 of the shielding container on the pallet 212 of the loading and unloading device. The lid 295 of the shielding container and the cap 151 of the cooling tube are remotely removed and mounted, respectively, on the base 292 of the shielding container or the casing 145 of the tube for cooling by a remotely controlled device 200 for moving molybdenum using a crane hook 266 that engages through the gripper 256 23, 24). The pallet 212 of the loading and unloading device slightly overlaps the end of the oil trap 208 to ensure a constant path for collecting possible drops of contaminated water that may appear during the return and handling of the cooling water supply unit 153 after irradiation of the loaded target holder 80. The pallet 212 of the loading and unloading device is also equipped with a drain hole 213 at the bottom of the pallet and an elbow with a cap for future drainage of decontamination fluids. The pallet 212 of the loading and unloading device is moved by two heavy duty pneumatic cylinders 209 with a piston stroke to cylinder diameter ratio of 10.0 '' × 15 '' bolted to each other with a closed loop arrangement. Bolting two cylinders with a closed loop layout to achieve three possible positions allows for two specific cylinder configurations to achieve a central position. The position of the storage 218 of the cap of the tube for cooling water is achieved with two extended cylinders. The position of the storage 216 of the lid of the shielding container is reached when one of the two cylinders is extended, and the position of the base 214 of the shielding container is reached when two cylinders are retracted.

Remote-controlled device 200. Molybdenum transfer is the primary remote manipulation mechanism for moving loaded target holders 80 with disks 85 of the target ¹⁰⁰ Mo to / from the cooling rack section 32 of the target unit 30 by providing all beam paths for horizontal (X) and vertical (Z) movements to remotely manipulated components. The remote-controlled molybdenum transfer device 200 has a gripper assembly 256 with a pneumatic clamping nozzle 264, a downward-looking camera (225), and light spots (not shown) of dual light emitting diodes (LEDs) for viewing from above and illuminating the work area in and around the remotely controlled device 200 movement of molybdenum.

An embodiment of the frame structure 230 is a four-leg structure bolted to the base frame 202 of the support frame. The frame structure 230 may be assembled from extruded aluminum structural frame components. The frame structure 230 has two main beams 232 extending parallel to the linear accelerator, which are tied together at each end to maintain accurate spacing and provide structural rigidity. Beams and crossbars provide support for the X-axis drive motor and gear boxes, flexible cable duct, electrical conduits and junction box. In the embodiment shown in FIG. 19 and 23, two main beams 232 directly supporting two linear drive motors along the X axis are located at a distance of about 440 mm from each other. A cart 240 for moving along the X axis is mounted between the linear drive motors 242 along the X axis. A cart 240 for moving along the X axis supports the motor, gear reducers and linear drive motors of the cart 250 for moving along the Z axis, as well as light emitting diodes creating light spots, and a chamber 225. The vertical axis drive motors 252 Ζ are spaced approximately 270 mm apart to be installed between the drive motors 242 along the X axis and provide a suitable clearance between the drive motors 252 of the оси axis for radios remote manipulation performed on the node 270 tilting rack (see. Fig. 25). A trolley 250 for moving along the оси axis supports the gripper assembly 256.

Suitable linear drive motors for both the X axis drive and the Ζ axis drive are internal ball screw profiles mounted on rails. Each assembly consists of a square extruded aluminum housing equipped with a trolley with internal circulating balls and with a composite ball screw pair moving the inner rail, driven by a rotating ball screw in 5 mm increments. The trolley for external loading is attached to the internal guided trolley through a cover tape made of stainless steel to protect the internal components of the drive from water splashes and dust. The drive mechanisms and gear reducers are lubricated at the factory with grease based on polyphenol-polyester, which has special properties of radiation resistance. Both movements along the X and Ζ axes are driven (by means of a power drive) on both linear drive motors to prevent the trolleys from seizing along the X and Ζ axes. Each of the drive motors along the X and Ζ axes is a radiation-resistant stepper motor equipped with a reliable (spring brake, with the application of energy to disconnect) the brake and brushless position sensor. Position sensors are provided for these external conditions, since the reading discs of the optical position sensors are prone to darkening and premature failure when exposed to strong radiation fields. The output drive shaft of each motor is connected to a safety clutch that is resistant to external influences and restricts torque to prevent mechanical overload of the drive components. The drive torque limiter on the X axis is set to a torque value of 1.13 Nm, and the drive torque limiter on the оси axis is set to a torque value of 2.26 Nm. If it is turned off (disengaged), the torque limiters will automatically attempt to reengage after each rotation of the motor shaft. As soon as the overload is eliminated and the speed decreases, they again engage. Since the torque limiters are bi-directional and are set outside the manipulator’s heaviest payload, they will not allow the lifting payload to go into uncontrolled mode if they disengage during lifting. They are not friction type limiters; therefore, they do not require constant adjustment. The engine speed is continuously adjustable through the control of the coordinate knob from zero to the maximum set speed of about 300 revolutions per minute (rpm). With a ball screw pitch of about 5 mm and all gear ratios of about 1: 1, a maximum linear drive motor speed of about 25 mm / s is ensured. On both drives along the X and ос axes, the protective safety clutch is attached to the input shaft of the gear reducer with double output shaft. The right angle bevel gear is connected to each corner of the gear gear with double output. The output shaft of each right angle bevel gear is connected to the input shaft of the linear drive motor through a connection. Since a gearbox with a double output shaft is a solid shaft, one output shaft rotates clockwise with respect to the base end and the other rotates counterclockwise. As a result, the pairs of linear drive motors consist of a right-handed ball screw and a left-hand ball screw. Each pair of ball screws of linear drive motors corresponds to a pitch of cutting their travel length by approximately 0.04 mm, which is less than the free play in the bearing at the end of the shaft. This correspondence prevents the two driven screws from seizing in relation to each other when they are joined through a rigid collecting trolley along the X or Z axes.

The total range of movement for linear drive motors is approximately 1850 mm in the direction of the X axis and approximately 1250 mm in the direction of the Z axis. However, proximity sensors are located near the end points of movement to prevent the movement of the internal drive trolleys in the end areas of movement. Consequently, the actual range of movement is approximately 1800 mm and 1200 mm, respectively, in the direction of movement along the X and Z axes. Positions near the proximity sensor along the X axis and above the по axis are set as the initial position of the remotely controlled device 200 for manipulating molybdenum for zeroing the reading of the position sensor data. All movements with remote control are monitored by a television camera of a cable television system, from at least two camera viewpoints, for example, from above and in an orthogonal projection, to guarantee the correct positioning, alignment and engagement of remotely controlled equipment.

Light spots can be provided, for example, as light spots from double light emitting diodes (LEDs) to guarantee the ability of the operator to perceive depth through the use of shadows. To enable this, each light source is individually controlled. Cameras are color cameras that support networking, characterized by the ability to pan, rotate and zoom the image.

The gripping unit 256 (FIG. 24) is a miniature, specially designed lifting device that engages and lifts with the help of a pneumatic gripping nozzle 264 either a target holder 80 or a crane hook 266 together with the payload. The engagement with any of these components is made first in the horizontal direction of movement to the center of the component in the pneumatic gripping attachment nozzle 264, and then in the vertical direction to come into contact and lift the component. To allow horizontal alignment, the grip frame 258 has a fork shape with two conical teeth leading to an open semicircular ring. The teeth and ring have a protrusion on the lower edge. This protrusion engages with the underside of the flat surface provided on both lifting components.

Since this illustrative embodiment of the invention does not have any vertical parts on the protrusion of the gripping frame 258 to resist horizontal sliding of the component to be lifted, the gripping is equipped with a pneumatic clamping cylinder 264 with a spring that inserts the plunger tip into its corresponding recess in the upper part any of the lifted components. The tip of the plunger enters this recess and applies a force of approximately 175 N (40 lbf) to ensure that the lifted component does not slip out of the grip during operation. When the locking plunger engages, the component is effectively locked in the grip. However, to avoid locking the component in the grip, the retracting spring plunger will automatically retract after the air supply to it has ceased. Unintentional air losses will also lead to the discharge of the plunger, but this does not amount to loss of the component. It simply means that the component could slide forward and fall out of the grapple if sufficient horizontal forces were created by impact or rapid deceleration. The clamping cylinder also provides a degree of mechanical conformity in the horizontal direction during operation of the hook coupler. The conical shape surrounding the flat engagement portion on the hook coupler allows it to oscillate on the grapple in the forward and backward directions. Easy swaying is necessary when it is necessary to pass along an arc path for the operation of tipping the rack. The plunger allows this swinging motion to be achieved without the need for disengagement.

To facilitate horizontal movement, the gripper assembly 256 may be equipped with three miniature ball-mobile ball assemblies 257 on the bottom of the gripper housing. These ball mobile units 257 allow the gripping unit 256 to roll along the surface when moving horizontally. Ideally, the gripping assembly 256 is lowered until the ball-movable assemblies 257 make light physical contact with the corresponding mating surface for the gripping component. Then they act as a positive downward stop. However, since the manipulator is not equipped with any feedback on the applied force, and all operations are performed with remote control, a certain degree of vertical mechanical compatibility is already built into the grip. The upper housing of the gripper assembly 256, which is attached to the lower part of the trolley 250 for moving along the Z axis, is bolted to the lower housing of the gripper frame structure 258 via a spring-loaded sliding sleeve 254 (springs 259). This arrangement of the sliding sleeve allows for an overturn of about 10 mm in the vertical direction downward without overloading the drive along the Z axis, without causing unintentional tripping of the protective torque limiter. This also limits the force on the ball mobile units 257 to allow smooth horizontal movement when rolling. The springs 259 only allow a vertical run down, but they do not form part of the load path when lifting.

Another exemplary embodiment of the present disclosed invention relates to a tipping rack, both to a part of equipment for remote manipulation, and to part of equipment remotely controlled. A suitable tipping rack assembly 270 is shown in FIG. 25, 26 and as a whole comprises: a welded construction of the rack, a base of the rotary guide with a lever arm assembly and a rack support assembly. The tipping rack assembly 270 is used to support the cooling tube assembly 153 carrying the target holder 80, while the cooling tube assembly 153 is lowered together with pivoting from a vertical position to a horizontal position, while orienting itself in such a way as this is necessary due to rotation with the capture unit 256 inside the remotely controlled device 200 for manipulating molybdenum. The rotation of the target holder 80 is necessary in order to orient it (1) vertically for insertion into the shielded container 290 and removal from it, and (2) horizontally for insertion into the tube assembly 153 for cooling and removal from it, while the assembly 153 is inserted into meshing with the tilt stand assembly 270 after the assembly 270 has been moved down with a rotary movement to the horizontal position.

Tilt leg assembly 270 includes a welded strut structure engaged to rotate the base of the rotatable rail. A suitable representative welded stand structure (best seen in FIG. 25) contains a pair of elongated corner metal profiles 274 spaced apart by an upper support plate 272 and a lower support plate 273. The support plates 272, 273 are structurally reinforced at this point with reinforcing bars 275. The upper support plate 272 and the lower support plate 274 are provided with matching cone-shaped slotted holes having arched ends for containment and positioned I in which the tube assembly 153 for cooling. The cooling tube assembly 153 is supported on the upper support plate 272 by placing a retaining ring 162 of the cooling tube assembly 153 resting on this plate on it. The lower support plate 273 provides the necessary 'second support point for the tube assembly 153 for cooling when it is in a horizontal position. The tilt-up welded construction has three round crossbeams extending between the two main bearing angles. The upper crossbar 276 of circular cross section (also defined as the upper round shaft) can engage with the crane hook 266 in conjunction with the gripper assembly 256 to raise and lower the tipping arm assembly 270. The upper round crossbar 276 is provided by two cone-shaped disks positioned around the center of the crossbar 276 to guide the crane hook 266 to the desired position. The lower circular crossbar 284 (also referred to as the lower round shaft) serves as a pivot point for lowering the tipping column assembly 270 to a horizontal position. An intermediate crossbar 279 of circular cross section (also defined as an intermediate shaft) acts as a stopper when the tipping stand assembly 270 rises to a vertical position, and also acts as an activating mechanism for the lever arm 286 (FIG. 26) when the tipping stand assembly 270 is lowered to horizontal position. The ends of the lower crossbar 284 of circular cross section and the intermediate crossbar 279 of circular cross section pass through the sides of elongated corner metal profiles 274.

The tipping rack assembly 270 is provided with a rotatable rail base that cooperates with the welded tipping rack structure to lower the tipping rack assembly 270 270 into a horizontal position and raise the tipping rack to a vertical position by turning. The base of the pivoting guide has a lower bar 284 to which a pair of mating spaced side plates 282 are securely fixed. These side plates 282 are provided with: (1) an upper inclined edge, Lowering from the first side end to the opposite side end, (2) matching vertical guides slot holes that are parallel and adjacent to the "long" side ends of the side plates 282, (3) matching vertical guide slot holes, which which are parallel and adjacent to the “short” side ends of the side plates 282, (4) matching the lower crossbars 287, fixed across the matching vertical guide slit holes adjacent to the long side ends of the side plates 282 in a selected first position above the lower beam 284, and (5) matching upper crossbars 288 fixed across matching vertical guide slit holes adjacent to the long side ends of the side plates 282 in the selected first position and higher than the lower crossbars 287. The ends of the lower crossbeam 284 of circular cross section extending outward from the elongated corner metal profiles 274 also extend outward through matching vertical guide slit openings adjacent to the long side ends of the above side plates 282 between the lower crossbars 287 and the upper crossbars 288. The ends of an intermediate crossbar 279 of circular cross section passing through the sides of elongated corner metal profiles 274 also extend outward through matching vertical apravlyayuschie slots adjacent long side ends above the side plates 282 above the shoulder 288. The upper cross-arm assembly 286 mounted rotatably on the lower plate 284.

The slotted holes on the side plates 282 capture, guide and position the ends of the lower crossbar 284 of circular cross section and the intermediate crossbar 279 of circular cross section, which extend outward through the sides of elongated corner metal profiles 274. In the vertical orientation, the ends of the lower cross bar 284 of circular cross section are captured in “long” vertical guide slit openings between the lower cross members 287 and the upper cross members 288, while the ends of the intermediate cross-section 279 of the circular cross section are gripping are located inside the “long” vertical guide slit openings above the upper crossbars 288, thereby keeping the tipping column assembly 270 in a vertical orientation. During the operation, when the cooling tube assembly 153 is mounted on / on the tipping rack assembly, the lower base plate 284 of the pivoting rail is mounted on four pins on the dropper, which serves as a mounting point 219 (see FIG. 20) for the tipping strut assembly 270 . In the case where it is necessary to move the tipping stand assembly 270 from vertical to horizontal, or vice versa, the upper round crossbar 276 is engaged with the crane hook 266 attached to the gripper assembly 256 of the remotely controlled molybdenum handling device 200. The tipping leg assembly 270 can be raised until the outwardly extending ends of the lower round crossbar 284 abut against the upper crossbars 288. In this position, the outwardly extending ends of the intermediate crossbar 279 of the round cross section come out of the "long" vertical guide slit holes in the side plates 282. Due to the remote control of the device 200 for manipulating molybdenum, the node 270 tipping rack will be lowered by turning from a vertical position horizontal position due to the remotely controlled movement of the gripping unit 156 in a horizontal plane along the base 202 of the supporting frame, while at the same time lowering the upper part of the tipping stand unit 270, so that the outgoing ends of the intermediate crossbar 279 of circular cross section slide along the inclined upper edge, this falling down from the end of the first side to the end of the opposite side of the side plates 282, thus lowering the upper part of the tipping unit 270 with rotation I rack. When the outwardly extending ends of the circular crossbar 279 reach the end of the inclined upper edge of the side plates 282, they are stopped by coming into contact with the “short” vertical guide slit holes in the side plates 282. In the fully lowered position, the tipping rack assembly 270 is supported by the introduction into engagement of its upper supporting plate 272 with the support 221 of the tipping rack provided on the dropper (Fig. 20, 26). When the tipping leg assembly 270 has lowered by turning, a portion of the intermediate cross-section of the circular cross section located between the elongated corner metal profiles 274 presses down one end of the lever arm 286. This causes the other end of the lever arm 286 to rise. The rising end of the lever arm 286 is provided with a rounded protruding tip (not shown) that contacts the target holder 80 engaged by the cooling water supply tube assembly 153 and lifts it several millimeters to allow the pneumatic clamping nozzle 264 of the gripper assembly 256 to properly engage engagement with the holder 80 of the target to remove it from the node 153 of the cooling water supply tube.

The operation process of the device 10 of the linear accelerator of electron beams of high energy of the present invention generally comprises the following steps.

The first step is to prepare the target discs with molybdenum-100. Molybdenum disks can be from natural molybdenum powder (with the presence of Mo-100 isotopes in an amount of 9.6%) or from highly enriched Mo-100 powder. Mo-100 powder can be finely ground or otherwise prepared powder before it is sintered or placed in a mold to form a disk. The mold is placed in a hydraulic press and then the discs are compressed. Pressed discs are nominally about 15 mm in diameter and about 1 mm in thickness. Subsequent sintering is carried out at high temperatures in a furnace with a rarefied or inert atmosphere, which causes shrinkage of the disks by approximately 4% in diameter and 3% in thickness. After compression and sintering, individual target disks are manually loaded into the target holder 80, and the loaded target holders 80 are manually loaded into the lead-lined shielded container 290. Manipulate the Mo-100 during preparation and pressing in the form of disks before sintering and subsequent loading of disks after sintering into the target holder 80 is preferably made inside the glove box to limit the dispersion of molybdenum powder to and from the outside of the production environment. After being removed from the glove box, the loaded shielded container can be lifted by a crane hook that engages with the handle 296 on the cover 295 of the shielded container (Fig. 22), and then can be moved by a bridge crane (not shown) to its location on the loading pallet 212 unloading device, lowering the base 292 of the shielded container onto the pins 214 provided for this on the pallet 212 of the loading and unloading device (Fig. 19, 21). After the lid 295 of the shielded container is depressurized from the base 292 of the shielded container by unlocking the handles 294, the lid 295 of the shielded container is moved by a crane to the pallet 212 of the loading and unloading device and placed in the storage 216 provided for this purpose in the pallet 212 of the loading and unloading device. Then, the cap of the cooling water cap 151 is removed from the cap assembly 141 of the cooling water tube (FIG. 18 (A), 18 (B)), which extends upward from the casing 44 of the cooling water tube connecting to the target irradiation chamber 42 (FIG. 9) using the node 156 capture remote-controlled device 200 for manipulating molybdenum and is placed in the storage 218 provided for this purpose in the pallet 212 of the loading and unloading device. The upper part of the cooling water supply tube assembly 153 is engaged through the gripping assembly 156, lifted from the cooling water tube casing 44 and placed in the tipping rack assembly 270 by positioning the holding ring 162 of the cooling water tube on the upper support plate 272 of the tipping strut assembly 270. . Then, the welded construction of the tipping rack moves from a vertical position to a horizontal position, as described previously, due to the remotely controlled gripping unit 256. Then, the gripping unit 256 is remotely controlled to engage the slotted holes 82 at the end of the target holder 80 with the pneumatic gripping clamp 264, after which, by remote control, the target holder is removed from the base of the shielding container 292 and inserted into the holder 105 of the cooler tube body and fixed therein at the lower end of the cooling water supply tube 154. Then, the welded structure of the tipping rack moves from a horizontal position to a vertical position due to the remotely controlled gripping unit 256. Subsequently, the gripping unit 256 is used to remove the loaded cooling water supply tube assembly 153 from the tipping rack assembly 270, and then lowers the loaded cooling water supply tube assembly 153 into the casing 44 of the cooling water tube until the target holder 80 enters the chamber 42 target irradiation. Then, the target holder 80 is accurately positioned and aligned by remotely manipulating the cooler supply tube 103 (or the cooling water supply tube assembly 153) to maximize exposure to the photon flux generated by the bremsstrahlung section 70. Then, the upper sleeve assembly of the cooling water supply pipe 141 is sealed in the casing 44 of the cooling water pipe by installing a cap 151 of the cooling water pipe. Then, a first supply of pressurized cooling water is made to the hermetically attached cooling water supply pipe 50 for separately circulating the cooling water through the brake radiation converter section 70. Next, the second cooling water pressurized to sealingly attached cooling water supply tube 46 for separately circulating cooling water through the target holder 80, wheels 85 and the Mo target ¹⁰⁰ irradiator chamber 55 chamber 42 target irradiation. Then, power is supplied to the electron beam linear accelerator 20 so that it produces an electron beam to bombard the tantalum plates 26 placed inside the bremsstrahlung section 70 to create a flow of bremsstrahlung photons so as to irradiate the target holder 80, into which many disks 85 of the target ¹⁰⁰ Mo . It is advisable, when using the device 10 of the high-energy electron beam accelerator disclosed here, containing a linear electron beam accelerator 20 with parameters of 35 MeV, 40 kW, for irradiating the target holder containing a plurality of target discs of ¹⁰⁰ Mo, irradiate the target holder and discs for a period of time in the range of from about 24 hours to about 96 hours, from about 36 hours to about 72 hours, about 24 hours, about 36 hours, about 48 hours, about 60 hours, about 72 hours, approximately 80 hours, approximately 96 hours. After irradiation of the target discs of ¹⁰⁰ Mo for a selected period of time, power is no longer supplied to the linear electron beam accelerator 20, two sources of cooling water supply are turned off, and cooling water is discharged from the target irradiation chamber 42. The cooling water supply is disconnected from the water inlet pipe 46, after which the cooling water pipe cap 151 is disconnected from the cooling water pipe assembly 141 via the remote control of the capture unit 256 of the remote controlled molybdenum manipulating device 200 and placed in the storage 218 provided for this purpose in the pallet 212 of the loading and unloading device. Then, using the remote control of the capture unit 256, manipulations are made with the cooling water supply tube assembly 153 to reliably connect it to the target holder 80, after which the cooling water supply tube assembly 153 is removed from the cooling water pipe casing 44 and placed in the tilt assembly 270 racks by positioning the retaining ring 162 of the Cooling water tube on the upper support plate 272 of the tipping rack assembly 270. Then, the welded construction of the tipping rack is moved from a vertical position to a horizontal position, as described previously, by remote control of the gripping unit 256. Then, the gripper assembly 256 is remotely manipulated to engage the slotted holes 82 at the end of the irradiated target holder 80 with the pneumatic clamping nozzle 264, after which the irradiated target holder 80 is removed from the base 292 of the shielding container and inserted into the base 292 of the shielding container control node 256 capture. Then, the lid 295 of the shielding container is placed on the base 292 of the shielding container by the gripping unit 256 and locked in place by engaging the handles 294 of the shielding container with the lid of the shielding container. The shielding container 290 can in this case be moved with a bridge crane into the glove box to remove the irradiated target holder 80.

At this point in the process, an additional solution is to transfer the target holder 80 with irradiated target discs of ¹⁰⁰ Mo to a lead-lined container to send it to equipment for recovering ^99m Tc from molybdenum. Alternatively, a target holder 80 with irradiated target discs of ¹⁰⁰ Mo can be remotely moved to a chamber for working with highly active substances, in which ^99m Tc can be separated and recovered from irradiated target discs of ¹⁰⁰ Mo using equipment and methods known to those skilled in the art. this technical field. Examples of ^99m Tc recovery and recovery equipment include the TECHNEGEN isotope separator (TECHNEGEN is a registered trademark of NorthStar Medical Radioisotopes LLC, Madison, WI (WI, Wisconsin). After the recovery of ^99m Tc has been completed, ¹⁰⁰ Mo is reduced, dried, and converted to sintering discs using equipment and methods known to those skilled in the art.

The exponential device of a linear high-energy electron beam accelerator for generating an electron beam with a power of 40 kW, 35 MeV, which is converted into a flow of inhibitory photons for irradiating a plurality of ¹⁰⁰ Mo targets to produce ⁹⁹ Mo due to a photonuclear reaction on ¹⁰⁰ Mo targets, disclosed here has the ability to produce based on a 24-hour 24-hour mode of operation from about 50 curies (Ci) to about 220 curies, from about 60 curies to about 160 curies, from about 70 curies to about 125 Ci, from about 80 curies to about 100 curies of ⁹⁹ Mo of a plurality of irradiated target ¹⁰⁰ Mo discs having weight in the aggregate value of from about 12 g to about 20 g, from about 14 g to about 18 g, from about 15 g to about 17 Admitting a 48 hour regimen for the decay of ⁹⁹ Mo from a plurality of irradiated target discs of ¹⁰⁰ Mo will result in daily production from about 35 curies (Ci) to about 65 curies, from about 40 curies to about 60 curies, from about 40 curies (Ci ) to when about 60 curie, from about 45 curie to about 55 curie ⁹⁹ Mo for shipping to nuclear pharmaceutical companies.

It should be noted that although the described embodiment of a device with a linear electron-beam accelerator of high energy refers to the power of a linear electron accelerator of 40 kW, 35 MeV, for producing ⁹⁹ Mo from a plurality of targets of ¹⁰⁰ Mo, the device can be scaled to obtain an electron beam with a power of approximately 100 kW, or alternatively, reduced in size to produce an electron beam with a power of approximately 5 kW.

Claims (22)

1. Device for the production of molybdenum-99 ( ⁹⁹ Mo) from a variety of targets of molybdenum-100 ( ¹⁰⁰ Mo) using a photonuclear reaction on targets of ¹⁰⁰ Mo, containing: a linear accelerator configured to generate an electron beam with a power of at least 5 kW to about 100 kW of power, a water-cooled transducer configured to receive an electron beam and convert it into a stream of bremsstrahlung photons with an energy of at least 20 MeV to about 45 MeV, a water-cooled component with irradiated targets, intended for receiving a flux of inhibitory photons, the component with irradiated targets has a camera for receiving a target holder containing a plurality of target discs of ¹⁰⁰ Mo, installing said holder in the chamber with the possibility of removing it and positioning the specified holder in the chamber, a remote controlled capture unit configured to move, while the capture unit is configured to engage and disengage the end of the target holder. 2. The device according to p. 1, in which the Converter contains at least one metal plate placed in such a way that it intersects the electron beam formed by a linear accelerator. 3. The device according to claim 2, in which the metal plate is a copper plate, or a cobalt plate, or an iron plate, or a nickel plate, or a palladium plate, or a rhodium plate, or a silver plate, or a tantalum plate, or a tungsten plate, or zinc plate, or plate of alloys of these metals. 4. The device according to claim 1, comprising a cooling tube assembly configured to connect to and disconnect from the target holder, the cooling tube assembly being configured to circulate the cooling fluid through the target disks ¹⁰⁰ Mo. 5. The device according to claim 4, in which the cooling tube assembly comprises a cooling fluid supply pipe comprising a plurality of guide ribs and shielding a cooling tube for shielding the flow of brake photons. 6. The device according to claim 5, in which the component with the irradiated targets comprises a target alignment component for positioning and aligning the target holder for maximum intersection with the flow of inhibitory photons. 7. The device according to claim 1, comprising equipment for remotely controlled delivery of the target holder and transfer of target disks ¹⁰⁰ Mo irradiated by photons into the container for shipment. 8. The device according to claim 1, containing a hot chamber for receiving a target holder accommodating ¹⁰⁰ Mo target disks irradiated with photons and for processing said ¹⁰⁰ Mo target disks irradiated with photons to separate and recover 99m technetium ( ^99m Tc) from them. 9. The device according to claim 1, comprising a removable protective enclosure surrounding the linear accelerator, a component with irradiated targets. 10. The device according to p. 9, containing a frame structure made with the possibility of its installation on top of the protective fence, and the remote controlled capture unit is made with the possibility of movement along the frame structure and inside it. 11. The device according to p. 1, containing the first cooling system, made with the possibility of tight connection with the specified Converter for circulation through it a cooling fluid. 12. The device according to p. 4, containing a second cooling system made with the possibility of tight connection with the specified extended cooling rack for circulation through it of a cooling fluid. 13. A method for producing molybdenum-99 ( ⁹⁹ Mo) from a plurality of molybdenum-100 targets ( ¹⁰⁰ Mo) using a photonuclear reaction on ¹⁰⁰ Mo targets, in which: forming an electron beam using a linear accelerator having a power of at least 5 kW to about 100 kW, form using a Converter the flow of bremsstrahlung photons from the specified electron beam, with an energy of at least 20 MeV to about 45 MeV, irradiating a plurality of target discs of ¹⁰⁰ Mo held in the target holder for receiving a flow of bremsstrahlung photons, cool the specified Converter and the photon irradiated target discs of ¹⁰⁰ Mo and the target holder is moved using a remotely controlled capture unit configured to engage and disengage the end of the target holder to separate and recover 99m-technetium ( ^99m Tc) from the ¹⁰⁰ Mo target discs irradiated with photons.

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