SK282898B6 - Protective device of nuclear power plant and method for reducing of the press in adjacent buildings of nuclear power plant - Google Patents

Abstract

The protective device of the nuclear power plant (4) in the form of the building surrounding the nuclear power plant (4), the inner wall (2) of which consist of thermally resistant material and is fixed on the specialised construction, whilst the inner wall (2) is equipped with the outlets that can be closed with the closing devices (8), for example by clappers, which can be open outwards, particularly under the pressure effect. The outlets on the inner wall (2) made by massive metal plates of the chamber nose (6, 7), placed between outer and inner walls, in which the filtration device (9) for the finest grains with exchangeable fillers for radionuclides filtration is placed and which comes to the annular space between the outer and inner walls (2), which creates the mixing space connected with the outer space by untightnesses of the outer cover (32).

Description

Technical field

The invention relates to a protective device of an atomic power plant in the form of a structure surrounding an atomic power plant when its inner walls consist of a heat-resistant material and are mounted on a support structure, the inner walls being provided with apertures with shut-off devices.

BACKGROUND OF THE INVENTION

It is known that pressure reactors in the event of failure do not explode, as the Russian RBMK Chernobyl reactors. However, even in the event of a failure of the pressure reactor, the pressure in the chambers of the building increases so that its walls can break and radioactive particles can escape. The best known failure occurred in the Western Pressure Reactor in Three - Miles - Island, Harisburg, Pennsylvania, USA in 1979 by partial melting of the core. The safety contamination metal tank above the reactor withstood a rapid increase in pressure and temperature, which later proved to be a critical condition.

A study by Atomwirtschaft, March 1981, by Hennies, Hosemann and Mayinger from Germany, entitled "The course and consequences of DWR failure of nuclear melting" explains the consequences of a failure of a pressurized reactor in a Western nuclear power plant with a contaminator. See pages 168-175. The graph on page 170, Fig. 1 shows the time course of pressure in the safety tank. The predicted breakdown time is 4.5 to 12.5 days, while the contaminant pressure has risen to 9 bar, being designed to a pressure of 5 bar. The criterion is a several-day supply of thermal energy, which can last longer than 12.5 days at the next pressure rise. The contaminator breaks if the pressure exceeds 9 bar, probably with similar consequences for man and the environment as the GAU disaster in Chernobyl 1986. To avoid any risk, protection is also expected for these devices with the way of contaminated media disposal.

WO 92/02 021 discloses an apparatus and method using a plastic barrier to absorb radioactive particles, gases, toxic liquids in the event of an atomic electric failure. Above the nuclear power plant are four pumpable independent roofs in the middle upwards and on the sides sealed on the ground. Air filtering systems have gaps between the four roofs. Tent roofs and underground tunnels are also reception facilities. This unstable barrier forms a protective cover, but is not a thermally stable measure and is not intended to reduce the pressure of contaminated media at KKW-GAU.

German patent 29 21 944 shows the protection of an atomic power plant with receiving rooms where radiation, gases, cooling water which is beyond control and small round receiving rooms for receiving apparatus and special containers can be received and concentrated by specially trained personnel. This embodiment is envisaged for minor failures, not for nuclear power plant failures without contaminant, and not for accepting large volumes at the degradable site.

Patent AT 405 110 discloses a protective device, approximately 150 m high, and having inner walls fitted with thin metal plates having tensile elements on their outer side to accommodate high bending loads. It is complicated and expensive to fit tension elements on metal beams and slabs on the perimeter of each horizontal row up to the dome. The self-contained building does not have an installed overpressure fuse, which would allow its removal and cleaning of the medium in case of a long-term increase in pressure and volume.

SUMMARY OF THE INVENTION

The aforementioned disadvantages are largely eliminated by the nuclear power plant protective device and the method of reducing the pressure in adjacent nuclear power plant structures according to the invention, which consists in that the predicted openings in the inner wall formed by solid metal plates open into a chamber located between the outer and inner walls. the finest grain filter device for filtering radionuclides with interchangeable inserts, which opens into an annular space between the outer and inner walls that form the mixing space and are connected to the outer space by leakage of the outer cover.

It is furthermore advantageous if the closing devices are arranged in pairs and one above the other diametrically opposite each other in the horizontal position of the cross-section of the building, wherein the closing devices are displaced relative to one another in the following cross-sectional planes.

It is further preferred that the shut-off devices are offset by 90 [deg.] In the circumferential direction.

Furthermore, it is advantageous if the chambers open into a suction duct which can be closed and outwardly directed by means of a closing device and into the space between the outer and inner walls, outside the chamber an additional suction device opens which can be connected to the suction device from the chamber.

Furthermore, it is advisable to install a sprinkler or spraying device in a large-volume protection in the form of an annular conduit which is connected to a reservoir of non-combustible liquid, for example water, the reservoir being in a reservoir located in the annular space between the outer and inner walls in the dome space; or the supply consists of a water supply.

Preferably, the sprinkler can be installed such that the annular guide is located at 2/3 of the height of the building.

It is preferable that an approximately horizontal path for the spray head mounted on the car is formed between the annular conduit and the ground, into which a movable conduit for supplying a non-flammable liquid, for example water, flows out of the interior through the wall opening.

Furthermore, it is expedient that the path is formed by a net belt which passes through the interior space to allow free passage of steam.

Furthermore, it is advantageous if the ends of the two ropes are fastened to the car and extend from two diametrically opposed positions of the interior.

Furthermore, it is advantageous if the inner wall is provided with a shielding coating which is applied to the inner wall, whereby a shielding against the output of the radioactive radiation can be guaranteed.

In order to control the technological measures, it is advantageous if several observation holes are provided on the inner wall which are fitted with protective glass.

By the method according to the invention, in the buildings surrounding the atomic power plant, in the event of an internal failure, the escaping pressure of the polluted gas is removed after purification of the gas, in particular of radioactive particles, additionally through a filter through the outer wall

BRIEF DESCRIPTION OF THE DRAWINGS

The drawing shows a protective device according to the invention with a method of pressure reduction and gas removal in three variants:

Fig. 1: A protective device according to the invention with a method of reducing pressure and decomposing gas built to atomic electricity with secondary structures in vertical section.

Fig. 2 shows a horizontal section of FIG. 1 along line a-a. Fig. 3 shows a partial section along line b - b of FIG. Second

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a protective device combined with a method for reducing the pressure and the amount of gas in the event of a failure of an eastern nuclear power plant with contaminant-free water pressure reactors as in technically old embodiments. The protective device can be made in a massive double-walled version with nuclear power plants running so that in the event of a breakdown, escaping gases and vapors of radionuclides can be trapped on one hand in a very voluminous space of the device. increasing the volume and pressure of the medium, which acts as a means of reducing the pressure and at the same time processing the medium, thereby releasing neutralized gases without radionuclides into the free space.

Technological measures and a special design of the inner wall will take place in four different places to remove the failure medium in the chambers by reducing the pressure and filtering the gases from the radionuclides and toxins before they are released into the atmosphere.

Further aspects of the invention provide for the protective device to be made in a low version with optimized technological measures. This is confirmed by the calculations of the Austrian Research Institute A-2444 Seibesdorf, Austrian Research Centers near Vienna, according to Dr. K. Miick June 17, 1999, on page 2: Model calculations may be performed in the event of a nuclear power plant failure for the expected heat sources (pressure, temperature, volume). On the other hand, it is possible to optimize the massive structure for the permissible volume at maximum pressure. The maximum pressure would attempt to lift the building from the ground for a large base area, but this is prevented by the massive interior walls with relatively thick metal plates and metal construction, causing a high ground load. According to technological measures, radioactive fluid can be removed at the deepest point.

According to FIG. 1, the protective device 1 is a massive inner wall 2 mounted on a base 3 and stands above an atomic power plant 4 with several adjacent structures 5. The inner wall 2 has two opposing chambers 6 near one of the ground, one of which is drawn 90 ° chambers 7, of which only one is also drawn and turned to level, with their articulated weight-loaded closing device 8, filtering device 9, as well as the associated closing valve 10 and suction device 11.

At 2/3 of the height of the protective device 1, there is a spraying device on the inner wall 2 with a duct 12 and nozzles 13, as well as a side-mounted net as a lane 14 on which the carriage 15 with the spray head 16 can be located and moved. and hose line 17 as well as the two ropes 18 required to change the position. In the dome area, there are two large water-filled tanks 19 with a common connecting line 20. Through the downcomer 21, after opening the shut-off valves 22 and 24, in the event of an emergency, the spraying device can be supplied with water-filled tanks 19; The corner manifold 26 also serves for further water supply to the hose line 17 and the spray head 16 with the shut-off valve 25 open and the line through the ascending line 27, the open shut-off valve 28 as well as with the actuator switched on. This drive apparatus is, for example, a pump that drives tap water 30 through a riser 27, open shut-off valves 25 and 28 as well as 24 to the spray head 16, as well as into an annular line 12 and sprays water through nozzles on cooled G AU media radially to the ring as well as centrally to the interior space 2 of the protective device. The tanks 19 are also still filled with water through the pump 29.

Fig. 2 shows a schematic representation of a metal structure 31 with an outer cover 32 at 2/3 of the height of the building and just above it. Furthermore, an exhaust device 33 for exhausting the rest gas is provided on the ground. An annular duct 12 is mounted on the inner wall 2 as well as a support network as a lane 14 where the carriage 15 with the spray head 16 occupies a central location and can be laterally displaced to the left and right from the protected position by two ends of the ropes 18. behind the inner wall 2.

Fig. 3 shows the inner wall of the protection 2 and the outer cover 32 with the ground chamber 6, as well as the weight-loaded closing device 8 and the filtering device 9. The suction device 33 located below can evacuate the resting medium from the inner space of the wall 2 through the chamber 6 , its open shut-off device 8, which is opened by flow, further through the lower half of the filter device 9, the open shut-off fitting 34 and the exhaust duct 35 and, on the other hand, must be switchable to the exhaust connection 36 so as the opening 37 is closed vertically and sealed at the same time by the weight-loaded closing device 8 in the unpressurized state on the inner wall 2.

Claims (12)

PATENT CLAIMS 1. A nuclear power plant protective device, the inner wall of which consists of a heat-resistant material and is fixed to a professional construction, the inner wall being provided with shut-off openings equipped with shut-off devices, for example flaps which open outwards, in particular against a compressive force; that in the openings in the inner wall (2) formed by the solid metal plates, there are chambers (6, 7) located between the outer and inner walls, in which the smallest grain filter device (9) with exchangeable radionuclide filtering inserts an annular space between the outer and inner walls, which forms a mixing space connected to the outer space by leaks of the outer cover (32). Protective device according to claim 1, characterized in that the closing devices (8) are arranged in pairs and one above the other diametrically opposite each other in the horizontal position of the cross-section of the building (1), the closing devices (8) being opposite to each other shifted. Protective device according to claim 2, characterized in that the closing devices (8) are offset by 90 ° in the circumferential direction. Protective device according to claim 1, characterized in that a suction duct (35) which can be closed and outwardly guided by means of a closing device (8) flows into the chamber (6, 7) and into the space between the outer wall and the inner wall outside the chamber. a device (33) which can be connected to a suction device from the chamber (6, 7). Protective device according to one of Claims 1 to 4, characterized in that an annular guide (12) is provided in the space surrounded by the inner wall (2) and is connected to a supply of a non-combustible liquid, for example water, by means of nozzles (13). the reservoir is located in a tank (19) which is located in the annular space between the outer and inner walls in the dome space of the building, or the supply is constituted by a water supply (30). Protective device according to one of Claims 1 to 5, characterized in that the annular guide (12) is located at 2/3 of the height of the building. Protective device according to one of Claims 1 to 6, characterized in that between the annular guide (12) and the ground there is a horizontal path (14) for a spray head (16) mounted on the vehicle (15) to which it can be moved. a conduit (17) for supplying a non-flammable liquid, for example water, which extends upwardly from the interior through a wall opening. Protective device according to claim 7, characterized in that the path (14) is formed by a net belt (14) which passes through the interior. Protective device according to claims 7 and 8, characterized in that the ends of the two ropes (18), which extend from two diametrically opposed positions in the interior, are fastened to the car (15). Protective device according to one of Claims 1 to 5, characterized in that the inner wall (2) is provided with a shielding layer which is applied to the cleaned inner wall. Protective device according to one of Claims 1 to 10, characterized in that the inner wall (2) has observation openings closed by a protective glass. Pressure reduction method in adjacent nuclear power plant structures according to claims 1 to 11, characterized in that in the buildings (1) surrounding the nuclear power plant (4), in the event of a failure in the interior, the pressure of the polluted gas is removed after purification from the radioactive particles. additionally through the filter (9) through the outer wall.