LT5391B - Method of irradiated fuel assemblies transportation from one reactor unit to other reactor unit for after - burning and equipment to realize the method - Google Patents

Abstract

Method of irradiated fuel assemblies transportation from one reactor unit to other reactor unit for after-burning and equipment to realize the method applies to the nuclear techniques, namely to the movement of irradiated fuel assemblies (IFA), and may be used for the nuclear reactor fuel after-burning if there are two or more reactor units. The method differs with the change of standard suspension of each transported IFA to the shortened transport suspension at special stand, and loading/unloading is performed using especially made shaft. Equipment complex to realize the method consists of container with jacket, transporter and container turn-over means, refueling machine at each reactor unit. New is that the complex contains the container with jacket, the transporter with container turn-over means, each reactor unit is equipped with a vertical through shaft made of several thick-wall cylindrical elements, which joints made as inner and outer truncated cones, entry of the shaft is placed in the rea

Description

Method and means of transporting irradiated heat generating assemblies from one power unit to another for combustion in another reactor unit

The invention relates to nuclear energy, namely, the transfer of irradiated heat release assemblies (REHPs). The invention can be applied to fuel combustion of nuclear reactors with two or more power units.

When the reactor of Unit 1 of the Ignalina Nuclear Power Plant is decommissioned for decommissioning, a large amount of SHFs with a burnout depth lower than the design will remain in the reactor core. Those REWS (about 1300 units) having a burn depth less than 0,8 average design burnout depth as defined in Lithuanian Pat. No. 4539 and no. No. 4945, can be reused for reactor loading at Unit 2 of the Ignalina Nuclear Power Plant. This would reduce the amount of fresh heat sink required for the operation of the Unit 2 reactor and reduce the amount of spent nuclear fuel that would have to be stored at the power plant.

An analog of the claimed technical solution may be U.S. Pat. 6359953, which discloses a method and apparatus for transporting nuclear fuel elements from a reactor to a storage site or for use in another reactor. According to this method, the nuclear fuel elements are placed in a special container with a separate case for each element and transported from one power unit to the storage or another energy unit, where the nuclear fuel elements are discharged from the container to the reactor core or other storage unit. Transported by a rail-moving platform.

The embodiment of this method consists of a special container with two separate trays for each element, a rail mounted conveyor and receiving 30 transfer units. At least one of the trays may move rails in a horizontal direction and be rotated about its longitudinal axis. Disadvantages include the fact that the container is designed for two elements only, there are no adequate means to protect the nuclear fuel from damage, and there is no system for removing excess pressure that may occur when the fuel warms up.

The closest technical solution is the method of transporting irradiated heat generator assemblies from one reactor unit to another in a reactor unit, known from the Russian patent RU 2180764 C. This method involves placing a conveyor with an LFGT in a container, preparing it for transportation, turning the container into another energy container. and unloading the REWS from the tray and loading it into the reactor core. There are two options for transportation: either a transport tube filled with water or a rails on which the transport container is placed.

The unit for transporting nuclear fuel from one power unit to burn it in the reactor of the second power unit consists of a container with a tray, a conveyor, a receiving / transfer / loading unit at each power unit, and means for conveying the container.

The transportation process can be completed:

- or pipes of several hundred meters in length connecting the first and second units with 15 two receiving gateways filled with water,

- or a platform moving along the corridor.

The above-described method of transporting an REF from one reactor unit to another in a reactor unit has many drawbacks and is unlikely to be suitable for actual use.

The use of a pipeline filled with water would require the construction of an appropriate supporting structure system, which would be cumbersome and increase the cost of the project.

The realization of such a method of transferring the RES would require material costs that would outweigh the burn-out effect of the fuel. The present embodiment overlooks the possibility of a fuel tray loss and fuel damage when transferring a container from a pool to a transport trolley, reducing nuclear and radiation safety when transferring fuel. In addition, in the event of failure of the transport trolley with the LWA in the water channel, there is no provision for fault elimination, as biosecurity in this case is the water that should be removed for repair.

The second version of the prototype transportation with a moving platform with container is only mentioned. The proposed technology does not provide for the disconnection of the suspension from the fuel module, which results in a doubling of the transmission unit dimensions. Neither of the stages provides for the airtightness check and the non-destructive inspection of the nuclear fuel, which are the main factors in the transport of the AED for combustion. Thus, the main disadvantage of the above-mentioned mode of transportation is that no technical measures have been proposed to ensure nuclear and radiation safety and the integrity of nuclear fuel.

The object of the invention is to create a technological process for transporting nuclear fuel from one reactor unit to another for reactor combustion, ensuring nuclear and radiation safety, while maintaining the airtightness and integrity of the SHPS.

The stated objective is achieved by transporting the LFGT from one reactor unit to another in the reactor unit, consisting of: preparation of the LLG for transportation, positioning of the container and tray conveyor in an upright position, positioning of the container with tray into the tray and loading the tray into the container. opening into a horizontal position, transporting a container from a first unit to a second unit, placing a container in an upright position, unloading a tray with an AED, unloading an AED, preparing and loading an AED into the core of a second unit. What's new is that in preparation for the shuttle for shipment, each shuttle's standard suspension on a special bench changes to a shortened transport shackle, a conveyor at a designated location in the building such that the container, following its opening from horizontal to vertical, with an additional step of transferring the tray from the container to the shaft and securing it to the shaft, then loading the tray in a sequential unloading-loading machine (IPM) ready for shipment, then placing the loaded tray with the SHE into a container, tilting the container to flushes the container and tray in a horizontal position, prevents shocks, closes the container with a lid, and when moving from unit one to unit two, the conveyor is positioned at a location within the building so that the container is upright after the second unit of energy. the shaft coaxially with it, checks for leaks and removes any excess pressure from the container to the ventilation system, opens the lid, holds the container upright, unlocks the tray with the LWA, and unlocks the LLR from the tray to prepare for transport to the reactor core replaces standard.

Up to six AEDs can be carried in the tray at a time.

The toolbox for carrying out this method comprises a container with a tray, a conveyor and container wrapping means, and in each power unit a loading / unloading machine (IPM). What's new is that the assembly includes a tray container, a conveyor with container tipping means, and each power unit is additionally equipped with a vertical borehole consisting of a number of thick-walled cylindrical elements whose junctures have a cut-in cone shape at the inlet to the reactor. In the hall, the shaft exit of the shaft is connected to a vertically positioned container, a movable biological protection is provided at the container-shaft connection, ensuring a single guiding path and protection of the service personnel.

One of the blocks of each shaft is equipped with an exhaust manifold connected to a special filtration system.

The shaft entrance is equipped with a loading unit with a tray locking mechanism in the shaft.

The container consists of a bottom housing, an airtight lid closed by the bayonet 10, a damper and a multi-function valve for drainage and excess pressure removal. The case is made to fit in a container and consists of a bottom plate, a top plate containing the nozzle and a main part consisting of a main tube connecting the nozzle and the bottom plate, around which spacers are provided with sockets for housing the tube tubes and protective plates, placed between the nozzle and main body so that the distance from the nozzle to the bottom plate is not less than the length of the NIR fuel module.

The nozzle consists of a housing with a flange, a braking device consisting of a spring-loaded brake shoe, springs and a bushing and transport suspension.

A stopping device with a damper ensures that the fuel is invulnerable in the event of a casing drop.

The transport hangers, which are connected to the SHIR, are shorter than the stationary hangers, have a system of ball-plug holders in the locking tray, which together with the tray flange and the protection plate ensure radiation protection.

The container vehicle uses an eight-axle rail conveyor equipped with a hydraulic container tilt system and a hydraulic platform leveling system, which consists of an optional four-hydraulic jack system on the conveyor. To protect against seismic effects, the conveyor is equipped with a system of six manual jacks.

In the present invention, during the preparation stage, a special bench performs the disconnection of the standard suspension from the AIR and its replacement by a shorter transport suspension. After the tightening, this suspension is changed to standard again. This reduces the dimensions of the tray, container and conveyor.

The tray ensures the correct positioning of the fuel being transported and ensures the minimum amount of bending allowed when moving the container from horizontal to vertical.

The combination of all of these features and equipment allows the development of a process for transporting the LAMF from one unit to another for reactor combustion in another unit, ensuring nuclear and radiation safety and airtightness.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of a set of equipment for transporting irradiated heat generating assemblies from one reactor unit to a second reactor unit for their combustion; 2. - Schematic of container placement under a shaft, FIG. 3 is a mechanism for locking the tray, FIG. 4 - Biosecurity, Figs.

- a diagram of a container with a tray inside, FIG. 6 is a diagram of the tray, FIG. 7 - Tray tip,

FIG. Fig. 8 - Transport suspension, Fig. 9 - Transport clamp with ball plug.

A set of transport means for transporting an REF from one reactor unit to another for combustion in another reactor unit consists of container 1 (Fig. 1), container rotating means (not shown), tray 2, conveyor 3, rail track 4, each of power units 5, 6. existing unloading machines (IPM) 7 and a safety chamber consisting of a vertical continuous shaft 8, 9 and a movable biological guard 10.

The vertical continuous borehole 8,9 (Fig. 2) consists of seven separate thick-walled cylindrical elements 11, the joints of which are made in the form of cut inner and outer cones. The entrance of the shaft 8, 9 is located in the reactor hall, the shaft exit is mounted in a single axis with a vertically raised container 1, a movable biological guard 10 is installed at the junction of the shaft 8, 9 and the container 1 to protect the service personnel from loading the SHF ionizing radiation tray. ) into and out of the container and to form a deflection tract between shaft 8, 9 and container 1).

One of the blocks 8, 9 of the shaft is equipped with a ventilation manifold 12, which is connected to a special filtration system which ensures purification of air before it is discharged into the atmosphere. The exhaust ventilation of the shaft 8, 9 ensures the directional movement of air simultaneously from the "polluted" reactor hall and the "clean" corridor into which the conveyor enters. In addition, ventilation ensures cooling of the nuclear fuel contained in the shaft. The upper part of the shaft is equipped with a loading device with a tray locking mechanism 13 (Fig. 2, Fig. 3), which consists of sliding holders 14, rods 15 which are pivotable by rotation or retractable holders 14. (Sliding holders 14 place a tray). 16 - Inner surface of the shaft.

Movable biosecurity 10 (Fig.4) consists of two movable carriages 18 mounted on rails (17) with blocks 19 and 20 movable from opposite sides of the coupling point of shaft 8, 9 and container 1, by engaging the interconnected contact surfaces by clamping the clamp 21, and enclosing the area of said joint.

Container 1 (Fig. 5) has a body with a removable bottom 22, an airtight lid 23 mounted on a conveyor, closed by a bayonet principle (closes or opens the container only when the container is horizontal) and a damper 24 in the bottom 22. a multi-function valve 25 for drainage and removal of possible excess pressure caused by the heating of the nuclear fuel during transport.

The tray 2 (Fig. 1, Fig. 6) comprises a nozzle 26 and a main part. The main part 2 of the tray consists of a main tube 27, six tray tubes 28, a spacer grille 29, a protective (biological) plate 30 and a lower plate 31 with holes for drainage of water.

The nozzle of the tray 26 consists of a housing in which the braking device is mounted. The braking device consists of brake pads 32 (preferably three), levers with a serrated sector 33, springs 34, bushes 35 (position 16 in Fig. 6 is the inner surface of shaft 8, 9 or container 1). For any reason, when the load on the gripper 13 is reduced, the spring 34, by stretching, pushes the brake block levers 33 which push the brake pads 32 outside the housing body. The pads 32, when in contact with the walls of the shaft 16, provide the required braking force.

The transport clamp (Fig. 8) consists of a housing 36 and a clamp 37. The clamp is intended for connection to the SHE main pipe. It facilitates the transport of REWS by unloading-loading machine (IPM) and other standard AE equipment, and also secures REWS in a tray. The transport hangers supporting the SHIR have a locking system in the tray using ball plugs 38 (Fig.9). For this purpose, the ball plug 38 with the nozzle 39 is slid onto the top of the transport suspension. The bushing 40 secures the clamp 37

The transport hangers are shorter than the standard ones, which results in a doubling of the length of the axle suspension. This means that the container length is almost doubled. In addition, the transport hangers, together with the case flange, provide the personnel with radiation protection against ionizing radiation.

The container vehicle uses an eight-axle rail conveyor 3 which has a container swivel system 1, a horizontal hydraulic system for setting the platform of the conveyor 3 and a braking system for securing and positioning the conveyor (not shown).

For setting the conveyor 3 with container 1 horizontally, the conveyor 3 has a system of four hydraulic jacks and for seismic protection a system of six manual jacks (not shown).

Container lid mounted on the conveyor platform.

It shall be closed or opened only when the container is in a horizontal position.

The following operations are carried out in the manner described above: In the first unit, IPM 7 unloads the reactor 5 from the reactor 5, transfers it to the storage tanks of the cartridges and checks their airtightness. After that, the REHPs are prepared for loading into the tray 8.

To this end, a fuel bench separates the fuel module from the standard suspension and connects it to the transport suspension.

The conveyor 3 with container 1 and tray 2 at a designated location beneath the shaft 8 in the building, opens the lid 23, is leveled in a horizontal position by a system of four hydraulic jacks and secured by seismic action secured by a six jacket system (not shown). Container 1 with tray 2 is lifted from a horizontal position to an upright position. The reactor hall crane lowers the shaft with a gripper and connects to the tray, followed by rails 17 on the opposite side of the shaft 8 and the container 1 on opposite sides of the bogies 18 with blocks 19 and 20, so that the blocks 19 and 20, when fitted, close the area of said joint and the clamp 21 for contacting each other with the contact surfaces form a movable biological guard. Tray 2 is lifted and secured by a crane in the reactor hall crane 8 to the loading unit. The ready-to-use IRM is loaded into tray 2 by filling the slots in tray 2, placing tray 2 in a reactor hall crane 2 into container 1. Turns container 1 into a horizontal position, closes with an airtight lid 23 and transports to another power unit 6.

In the next reactor unit operations are performed in reverse order:

The conveyor is located beneath the shaft 9 in the building 3. Thereafter, before opening the container lid 23, the flexible hose of the multi-function valve 25 removes any excess pressure from the cavity of the container 1 into a special ventilation system. Then opens the container lid 23. Aligns the platform of the conveyor 3 with four hydraulic jacks in a horizontal position, displaces the six locking jacks, and then lifts the container from a horizontal position to an upright position. The reactor hall crane lowers the shaft with a clamp and connects to the tray 2. The carriages 18 with blocks 19 and 20 are then pushed in the manner described above and the clamp 21. The reactor hall crane 2 is raised and secured in the shaft 9 loading device. The IPM SHF unloads one by one into the cartridges in the cartridge storage basin, and performs the SHF sealing.

then the transport pendulum is changed to the standard one and loaded into the reactor 6 reactor core 6 according to the procedure of the SHIR.

Provides a specific method of execution on the proposed device.

On the rails 4, there is formed an assembly consisting of a special vehicle, a conveyor 3 and a container 1, brought by rail 4 to the gate of the transport unit 5 on the transport corridor. Opens the corridor gate and delivers the conveyor 3 with a transport kit to the parking location using a special transport vehicle. The gates of the corridor shall be closed. According to the markings made in the corridor, the special vehicle is conveyed by the special conveyor 3 and secured directly under the deflector guard 8. The special vehicle is disconnected from the conveyor. The flexible cable connects the electrical equipment of the conveyor 3 to the fixed power supply system. Electricity is supplied to the actuator of the container 1 lid, to the pumps of the hydraulic station, to the control panel of the hydraulic station, when the hydraulic station is ready for operation. Levels the conveyor horizontally using hydraulic jacks. It then pushes out six manual jacks.

The lid 1 of the container 1 is sealed and the clamping device with the lid of the container 1 is pulled away from the opening of the container 1. Opens the multi-function valve 25 at the bottom of container 1. The operator lifts the container 1 from the horizontal position to the vertical position.

The reactor hall crane lowers the shaft with a clamp into the container and clamps it with the tray 2 contained therein. Pushes the block of movable biological guard 10 20. The crane is lifted by the crane 8 to the loading unit 13 where the tray 2 is locked. Detaches the bar with the gripper from tray 2.

Discharge-loading machine (IPM) ready-made SHDs are loaded one at a time into tray 2. After filling all 2 slots in the tray, the SHDs are locked in sockets with ball closures 38.

The crane tray 2 is lowered from the pit stop unit down to the full load in the container 1. As the gripper load decreases, the brake pads 29 expand, locking the tray 2 in the container 1.

By placing the tray 2 in the container 1, the movable biosecurity units 19 and 20 are spaced apart, and the rod gripper is disconnected. Raises the bar by crane, pulls it fully out of the shaft and puts it in storage.

Container 1 is lowered from the vertical position to the horizontal (transport) position. Attaches the lid with the clamping mechanism to the container and seals it, closes the valve 25, and checks the tightness of the container lid 23.

Relieves the support jacks and builds into transport position, releases the main hydraulic jacks, moves conveyor 3 to transport position.

It then disconnects the conveyor from the power supply system, seals the container lid, releases the conveyor brakes and connects the conveyor to a special transport vehicle. After checking the contamination of the surface of the container, conveyor 3 and special vehicle, decontamination is carried out if necessary. The vehicle 16 with the conveyor 3 is transported by rail 4 to the second power unit 6.

In the second power unit 6, the conveyor 3 with the container 1 and the tray 2 inside the building at a designated location beneath the shaft 9. Removes any excess pressure from the cavity of the container 1 through the valve 25 before opening the lid 23. Opens the container lid 23, opens the drain valve 25, sets the platform in a horizontal position and raises the container 1 to an upright position.

The crane 2 unloads the tray 2 with the crane from the container 1 to the loading unit of the shaft 9.

The IPM unloads the SWF from the tray 2 into the ready-made pencils, checks them for leaks, then replaces the transport rack with the standard one and loads the SHF into a second reactor 6. After unloading the SWR, the tray 2 is returned to the container 1.

The development of a method and toolbox for the combustion of nuclear fuel without compromising its airtightness and ensuring radiation and nuclear safety has two objectives:

• economic and • ecological.

The economic objective is achieved by the use of fission materials from the nuclear power plants during the decommissioning of the reactor. The ecological goal is achieved by reducing the amount of waste heat recovery kits used for storage in containers.

Claims (11)

DEFINITION OF INVENTION A method of transporting fuel of the first unit for its combustion in the reactor of the second unit, comprising the preparation of irradiated heat release assemblies (REFs) for transport, positioning of the conveyor with container and tray, upright container loading, and loading of the REF container. such as placing a container in a horizontal position, transporting a container from a first unit to a second, raising a container to an upright position, unloading a tray with an AED, unloading an AED, preparing and loading a second reactor into a reactor core; replaces each axle suspension on a special bench with a shorter transport hanger, conveyor (3) at a fixed location in the building such that the container (1), when lifted from a horizontal position to a vertical position, faces one shaft of the first power unit (5); e with the shaft (8), the loading of the SHIR is carried out with an additional step of transferring the tray (2) from the container (1) to the shaft (8) and securing it to the shaft (8), then to the tray (2) IPM) takes turns to prepare the shuttle for transportation, then moves the tray (2) with the shuttle into the container (1), tilts the container into a horizontal position, and aligns the conveyor (3) with the container (1) and the tray (2) , the container (1) is closed by a lid (23), and after passing from the first unit (5) to the second unit (1), the conveyor is positioned at a location so that the container 1 is positioned vertically after the second power unit (6). shaft (9) in one axis with shaft (9), checks for airtightness and removes any excess pressure from the cavity of the container (1) into the ventilation system, opens the lid (23), holds the container (1) in the upright position; buy elia in the shaft (9) and secures therein, unloads the LFG from the tray (2), preparing the LFG for loading to the reactor core of the second unit, replacing the transport suspension with a standard one. 2. A method according to claim 1, characterized in that up to six LIS are transported simultaneously. A set of means for implementing the method of claim 1 or 2, comprising a container (1) with a tray (2), a conveyor (3), and container conveying means, an unloading-loading machine (IPM) (7) in each of the power units (5). 6), characterized in that each of the power units is further equipped with a vertical through shaft (8, 9) comprising a number of individual thick-wall cylindrical elements (11) with joints made cut internal and external ¹¹ EN 5391 B cones and shafts The entrance (8, 9) is located in the reactor hall, the exit of the shaft (8, 9) is axially connected to the vertically raised container (1), the movable biological protection (10) provided at the junction of the shaft (8, 9) and the container (1). the formation of a guiding tract and the protection of service personnel. 4. A tool set according to claim 3, characterized in that one of the blocks of the shaft (8, 9) is provided with an exhaust ventilation manifold connected to a special filtration system. A tool set according to any one of claims 3 to 4, characterized in that a loading unit (13) with a tray (2) is installed at the entrance of the shaft (8, 9). 10 in the locking shaft (8, 9). 6. A tool set according to any one of claims 3 to 5, characterized in that the container (1) comprises a housing with a bottom (22), an airtight lid (23), closed by a bayonet principle, a damper (24) and a multifunction valve (25), which performs the functions of drainage and removal of excess pressure. 15th A device assembly according to any one of claims 3 to 6, characterized in that the tray (2) is made to fit inside the container (1) in length and consists of a bottom plate (31), an upper plate containing a nozzle (26). ) and a main part consisting of a main pipe (27) connecting the lower plate (31) and the nozzle (26), around which the slots (29) are provided 20 pipes (27), and a shield (30) enclosed between the nozzle (26) and the main body at a distance from the bottom plate of not less than the length of the REF fuel module (31). A set of tools as claimed in any one of claims 3 to 7, characterized in that the nozzle (26) has a flange housing with a braking device consisting of a braking device. 25 pads (32), levers (33) with serrated section, springs (34) and bushings (35), and transport hangers. A tool set according to any one of claims 3 to 8, characterized in that the transport hangers connected to the REH are shorter than standard hangers and have a system of ball plugs (38) in the locking tray (2). 30th 10. A tool set according to claim 3, characterized in that the vehicle uses an eight-axle rail conveyor having a hydraulic container tilting system and a hydraulic platform positioning system. A tool set according to any one of claims 3 to 4, wherein 12 EN 5391 B furthermore, for setting the conveyor (3) with the container (1) in the horizontal position, the conveyor is additionally equipped with a system of four hydraulic jacks and for protection against seismic loads a system of six manual jacks.