A marine reactor suppression and injection system

Abstract

The present invention relates to the technical field of safe utilization of nuclear energy, and specifically discloses a pressure suppression and injection system for a marine reactor, wherein the cavity between the containment and the reactor compartment is divided into a pressure suppression water tank, an isolation empty compartment, an injection tank, a water supply tank, and a water injection tank; a water collection well and a reactor enclosure are located in the reactor compartment, and the reactor is located in the reactor enclosure; the injection tank is connected to the reactor through a connecting pipeline, the water supply tank is connected to the reactor through a connecting pipeline, and the water injection tank is connected to the reactor through a connecting pipeline; a suction port B extends into the water collection well, is connected to a nozzle on the top of the reactor compartment through a connecting pipeline, a branch is drawn from the connecting pipeline and extends into the pressure suppression water tank, and a suction port A is provided at the end of the branch; a suction port C extends into the water collection well, and is connected to a low-pressure injection pump through a connecting pipeline. The present invention combines the pressure suppression and injection systems, and all equipment and facilities are arranged in the containment, realizing the actual demand for miniaturization of equipment and facilities related to marine reactors.

Description

Technical Field

[0001] The invention belongs to the technical field of safe utilization of nuclear energy, and in particular relates to a ship reactor suppression and injection system. Background Art

[0002] The main purpose of the reactor safety system is to ensure the emergency shutdown of the reactor, the removal of residual heat from the core and the integrity of the containment after an accident occurs, so as to limit the development of the accident and mitigate the consequences of the accident.

[0003] The reactor containment is a confined space that prevents the escape of radioactive materials when a nuclear reactor is in operation or an accident occurs. It also serves as a protective structure for the reactor compartment, protecting the equipment and systems in the reactor compartment from the adverse effects of external events.

[0004] Compared with land-based nuclear power plants, the design requirements for pressure suppression and injection systems for shipboard reactor compartments are significantly different. The space on ships or floating platforms is very limited, so the total volume of the reactor compartment is much smaller than the safety shell of the land-based reactor. Under accident conditions, the instantaneous release of high-temperature steam will cause the pressure in the cabin to increase much more than the safety shell of the land-based reactor, and the difficulty of achieving passive residual heat removal is also much higher than that of land-based nuclear facilities. In addition, the volume of the suppression pool and the water tank is also very limited. Obviously, the design of the land-based injection system is not suitable for the pressure suppression and injection design requirements of the reactor compartment of ships or floating platforms.

[0005] Therefore, it is particularly important to design a pressure suppression and injection system suitable for ships or floating platforms in combination with the design concept of ships or floating platforms. Summary of the invention

[0006] The object of the present invention is to provide a marine reactor suppression and injection system to avoid leakage of radioactive substances and core melting.

[0007] The technical solution of the present invention is as follows:

[0008] A marine reactor suppression and injection system, wherein the cavity between the containment and the reactor compartment is divided into a suppression water tank, an isolation empty compartment, an injection tank, a make-up water tank, and an injection water tank; a water collection well and a reactor enclosure are located in the reactor compartment, and the reactor is located in the reactor enclosure;

[0009] The injection box is connected to the reactor through a connecting pipeline, on which a normally open valve F, a check valve and a valve K are arranged in sequence;

[0010] The water supply tank is connected to the reactor through a connecting pipeline, on which valve G, a low-pressure injection pump, valve H, valve I and valve K are arranged in sequence;

[0011] A branch is provided on the pipeline connecting the low-pressure injection pump and the rear of the valve H and in front of the valve I, the branch is connected to the reactor, and a recirculation cooler and a valve K are provided on the branch;

[0012] The water injection tank is connected to the reactor through a connecting pipeline, on which valve C, a high-pressure injection pump, valve D, and valve K are arranged in sequence;

[0013] The total volume of water in the suppression water tank, injection tank, injection tank and make-up water tank is greater than the sum of the volumes of the water collection well and the reactor enclosure;

[0014] The water collection well is located at the rear side wall of the reactor compartment, close to the stern, to ensure that condensed water is effectively collected when the ship is in a stern trim state;

[0015] The suction port B extends into the water collection well and is connected to the nozzle on the top of the reactor compartment through a connecting pipeline. A branch line is drawn from the connecting pipeline and extends into the pressure suppression water tank. A valve A is provided on the branch line, and a suction port A is provided at the end of the branch line. A spray pump and valve B are provided on the connecting pipeline and behind the branch point.

[0016] The suction port C extends into the water collection well and is connected to the low-pressure injection pump and valve H through a connecting pipeline. A valve E is provided on the connecting pipeline.

[0017] There are two sets of low-pressure injection pumps and valves H, which are arranged in parallel;

[0018] There are two sets of high-pressure injection pumps and valves D, which are arranged in parallel.

[0019] A vent pipe A and a vent pipe B connected to the reactor compartment are respectively provided on the top of the water injection tank and the water makeup tank to balance the pressure inside and outside the liquid tank;

[0020] The water injection tank and the water replenishment tank are two separate water tanks or an integral water tank.

[0021] The height of the reactor enclosure is higher than that of the core, so as to ensure that the core can be submerged when water collects in the reactor enclosure.

[0022] Panel flat irons are arranged on the top and middle area of ​​the wall panels of the reactor enclosure well to prevent the wall panels of the reactor enclosure well from buckling.

[0023] The nozzles are arranged at equal intervals on the top of the reactor compartment in a spray ring or matrix arrangement.

[0024] If the space of the suppression water tank, injection tank, water injection tank and make-up water tank is insufficient, the space will be expanded into the isolation void compartment according to actual needs to adjust the volume of the suppression water tank, injection tank, water injection tank and make-up water tank, and ensure that the total volume of the suppression water tank, injection tank, water injection tank and make-up water tank does not exceed the total volume of the cavity between the containment and the reactor compartment.

[0025] When the reactor coolant pressure boundary is damaged due to a small breach, resulting in a loss of coolant accident, the reactor coolant system pressure and water level slowly decrease, valve C is opened, and the cooling water in the water injection tank is injected into the core of the reactor through the connecting pipeline, valve C, high-pressure injection pump, valve D, and valve K;

[0026] When a large groove loss of coolant accident occurs, the reactor coolant system pressure drops below the injection tank pressure, and the cooling water in the injection tank is injected into the reactor through the connecting pipeline, the normally open valve F, the check valve, and the valve K, flooding the core in the reactor in a short time to prevent the core from melting;

[0027] When the pressure continues to drop to the threshold, valve G is opened, and the cooling water in the water injection tank is injected into the core through the connecting pipeline, valve G, low-pressure injection pump, valve H, valve I, and valve K;

[0028] After a long period of low-pressure safety injection operation, the pressure and temperature of the reactor coolant system and the reactor compartment have been reduced and are in a relatively stable state, or when the water injection tank is emptied, the operating personnel will switch to the recirculation cooling stage according to the situation, open valve E to switch the low-pressure safety injection pump to suck the liquid in the water collection well through the suction port C, open valve J to re-inject the liquid into the core after cooling by the circulating cooler, and perform recirculation operation to continuously cool the core.

[0029] When a loss of water accident occurs in the primary circuit of the reactor or a main steam pipe rupture accident occurs in the reactor compartment, and the pressure in the reactor compartment rises to a certain threshold, the reactor compartment heat removal system is automatically put into operation, valve A is opened, and the spray pump is started to spray the water in the pressure suppression water tank into the reactor compartment through the suction port A, valve A, spray pump, valve B, and nozzle to reduce the pressure and temperature of the reactor compartment;

[0030] When the pressure and temperature of the reactor coolant system are reduced to a relatively stable operating condition, or the water source in the suppression water tank is emptied and enters the intermittent operation recirculation cooling stage, the condensed water after the reactor compartment is cooled gathers in the water collection well, and under the action of the spray pump, it returns to the sprinkler head through the suction port B and the corresponding connecting pipeline to continue spraying.

[0031] The remarkable effects of the present invention are:

[0032] (1) The present invention combines the pressure suppression and injection systems, and all equipment and facilities are arranged in the containment, thus meeting the actual demand for miniaturization of equipment and facilities related to marine reactors.

[0033] (2) The space of a shipboard reactor compartment is much smaller than that of a land-based nuclear facility containment vessel. The reactor compartment pressure limit under accident conditions is much higher than that of a land-based nuclear facility containment vessel. The present invention uses a pressure suppression water tank with pressurized conditions, which can still achieve spraying when a high pressure occurs in the reactor compartment.

[0034] (3) The present invention makes full use of the isolation compartment that should be usually provided in the marine reactor compartment as a pressure suppression water tank, an injection tank, a water injection tank and a water makeup tank, thereby effectively saving ship space.

[0035] (4) The present invention sets up the reactor enclosure as a water collection pit, which ensures the ability to flood the core and retain the molten material under severe accident conditions.

[0036] (5) The present invention ensures design safety redundancy by configuring equipment such as pumps and valves as backup devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a schematic diagram of the suppression and injection system principle;

[0038] Figure 2 A is a schematic diagram of containment compartment partition;

[0039] Figure 3 Schematic diagram of containment compartment partition B.

[0040] In the figure: 1 containment; 2 reactor compartment; 3 suppression water tank; 4 isolation void compartment; 5 injection tank; 6 make-up water tank; 7 injection tank; 8 water collecting well; 9 reactor enclosure; 10 panel flat iron; 11 reactor; 12 core; 21 spray pump; 22 low-pressure injection pump; 23 high-pressure injection pump; 24 recirculation cooler; 25 nozzle; 31 valve A; 32 valve B; 33 valve C; 34 valve D; 35 valve E; 36 normally open valve F; 37 check valve; 38 valve G; 39 valve H; 40 valve I; 41 valve J; 42 valve K; 51 suction port A; 52 suction port B; 53 suction port C; 54 vent pipe A; 55 vent pipe B. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] like Figures 1 to 3 A marine reactor suppression and injection system is shown, wherein the cavity between the containment 1 and the reactor compartment 2 is divided into a suppression water tank 3, an isolation void compartment 4, an injection tank 5, a make-up water tank 6, and an injection tank 7. A water collection well 8 and a reactor enclosure 9 are located in the reactor compartment 2, and a reactor 11 is located in the reactor enclosure 9.

[0043] The injection tank 5 is connected to the reactor 11 through a connecting pipeline, on which a normally open valve F36, a check valve 37 and a valve K42 are sequentially arranged.

[0044] The water supply tank 6 is connected to the reactor 11 through a connecting pipeline, and valve G38, low-pressure injection pump 22, valve H39, valve I40, and valve K42 are arranged on the connecting pipeline in sequence. There are two sets of low-pressure injection pump 22 and valve H39, which are arranged in parallel. A branch is arranged on the connecting pipeline behind the two sets of low-pressure injection pump 22 and valve H39 in parallel and in front of valve I40, and the branch is connected to the reactor 11, and a recirculation cooler 24 and valve K42 are arranged on the branch.

[0045] The water injection tank 7 is connected to the reactor 11 through a connecting pipeline, on which valve C33, high pressure injection pump 23, valve D34 and valve K42 are arranged in sequence. There are two sets of high pressure injection pump 23 and valve D34, which are arranged in parallel.

[0046] A vent pipe A54 and a vent pipe B55 connected to the reactor compartment 2 are respectively provided on the top of the water injection tank 6 and the water makeup tank 7 to balance the internal and external pressures of the liquid compartment.

[0047] The water injection tank 6 and the water replenishment tank 7 may be two separate water tanks or an integral water tank.

[0048] The total volume of water in the suppression water tank 3 , the injection tank 5 , the injection tank 6 , and the water replenishment tank 7 is greater than the sum of the volumes of the water collection well 8 and the reactor enclosure 9 .

[0049] If the space of the suppression water tank 3, the safety injection tank 5, the water injection tank 6 and the make-up water tank 7 is insufficient, the space can be expanded toward the isolation compartment 4 according to actual needs to adjust the volumes of the suppression water tank 3, the safety injection tank 5, the water injection tank 6 and the make-up water tank 7, as long as the total volume of the suppression water tank 3, the safety injection tank 5, the water injection tank 6 and the make-up water tank 7 does not exceed the total volume of the cavity between the containment 1 and the reactor compartment 2.

[0050] The water collection well 8 is rectangular and is located at the rear side wall of the reactor compartment 2, close to the stern, to ensure that condensed water is effectively collected when the ship is in a stern-tilted state. At the same time, the rectangular structure can also adapt to the ship structure design.

[0051] The height of the reactor enclosure 9 is higher than that of the core 12 , so as to ensure that the core 12 can be submerged when water collects in the reactor enclosure 9 .

[0052] Panel flat irons 10 are arranged on the top and middle area of ​​the wall panels of the reactor enclosure 9 to prevent the wall panels of the reactor enclosure 9 from buckling, usually in the form of welding.

[0053] The suction port B52 extends into the water collection well 8, and is connected to the nozzle 25 on the top of the reactor compartment 2 through a connecting pipeline. A branch is drawn from the connecting pipeline and extends into the pressure suppression water tank 3. A valve A31 is provided on the branch, and a suction port A51 is provided at the end of the branch. A spray pump 21 and a valve B32 are provided on the connecting pipeline and behind the branch point. The nozzles 25 are arranged at equal intervals on the top of the reactor compartment 2, and are arranged in a spray ring pipe or matrix manner.

[0054] The suction port C53 extends into the water collecting well 8, and is connected to the low-pressure injection pump 22 and the valve H39 through a connecting pipeline, and a valve E35 is provided on the connecting pipeline.

[0055] like Figure 3 As shown in the embodiment, taking into account the design of the fuel exchange channel in the reactor compartment, the water injection tank 6 and the water makeup tank 7 can be arranged in the top empty space between the containment vessel 1 and the reactor compartment 2; the injection tank 5 can be designed as a pressure cabin or a double-layer pressure container for long-term storage of pressurized nitrogen, so as to facilitate the installation and fixation of the spherical tank type pressure vessel in the cabin.

[0056] Safety injection system:

[0057] When the reactor coolant pressure boundary is damaged due to a small breach, resulting in a loss of coolant accident, the reactor coolant system pressure and water level slowly decrease, and valve C33 is opened. The cooling water in the water injection tank 7 is injected into the core 12 in the reactor 11 through the connecting pipeline, valve C33, high-pressure injection pump 23, valve D34, and valve K42.

[0058] When a large groove loss of coolant accident occurs, the reactor coolant system pressure drops below the injection tank pressure, and the cooling water in the injection tank 5 is injected into the reactor 11 through the connecting pipeline, the normally open valve F36, the check valve 37, and the valve K42, flooding the core 12 in the reactor 11 in a short time to prevent the core 12 from melting.

[0059] When the pressure continues to drop to the threshold, valve G38 is opened, and the cooling water in the water injection tank 6 is injected into the core 12 through the connecting pipeline, valve G38, low-pressure injection pump 22, valve H39, valve I 40, and valve K 42.

[0060] After a long period of low-pressure safety injection operation, the pressure and temperature of the reactor coolant system and the reactor 11 cabin have been reduced and are in a relatively stable state, or when the water injection tank 6 is emptied, the operating personnel will switch to the recirculation cooling stage as appropriate, open valve E35 to switch the low-pressure safety injection pump 22 to suck the liquid in the water collection well 8 through the suction port C53, open valve J41 to re-inject the liquid into the core 12 after cooling by the circulating cooler 24, and perform recirculation operation to continuously cool the core 12.

[0061] Suppression system:

[0062] When a loss of water accident occurs in the primary circuit of the reactor or a main steam pipe ruptures in the reactor compartment, and the pressure in the reactor compartment rises to a certain threshold, the reactor compartment heat removal system is automatically put into operation, valve A31 is opened, and the spray pump 21 is started to spray the water in the suppression water tank 3 into the reactor compartment through the suction port A51, valve A31, spray pump 21, valve B32, and nozzle 25 to reduce the pressure and temperature of the reactor compartment.

[0063] When the pressure and temperature of the reactor coolant system are reduced to a relatively stable operating condition, or the water source in the suppression water tank 3 is emptied and enters the intermittent operation recirculation cooling stage, the condensed water after the reactor compartment is cooled gathers in the water collection well 8, and under the action of the spray pump 21, returns to the spray head 25 through the suction port B52 and the corresponding connecting pipeline to continue spraying.

[0064] The above are only preferred embodiments of the present invention and are not intended to limit the scope of the present invention. All equivalent changes and modifications to the shapes, structures, features and spirits described in the claims of the present invention should be included in the claims of the present invention.

Claims

1. A marine reactor suppression and injection system, characterized in that: The cavity between the containment vessel (1) and the reactor compartment (2) is divided into a pressure suppression water tank (3), an isolation void compartment (4), an injection tank (5), a water replenishment tank (6), and an injection tank (7); a water collection well (8) and a reactor enclosure (9) are located in the reactor compartment (2), and a reactor (11) is located in the reactor enclosure (9); The injection box (5) is connected to the reactor (11) through a connecting pipeline, and a normally open valve F (36), a check valve (37), and a valve K (42) are sequentially arranged on the connecting pipeline; The water supply tank (6) is connected to the reactor (11) through a connecting pipeline, on which a valve G (38), a low-pressure injection pump (22), a valve H (39), a valve I (40), and a valve K (42) are sequentially arranged; A branch is provided on the pipeline connecting the low-pressure injection pump (22) and the valve H (39) at the rear and in front of the valve I (40), the branch is connected to the reactor (11), and a recirculation cooler (24) and a valve K (42) are provided on the branch; The water injection tank (7) is connected to the reactor (11) through a connecting pipeline, on which a valve C (33), a high-pressure injection pump (23), a valve D (34), and a valve K (42) are sequentially arranged; The total volume of water in the pressure suppression water tank (3), the injection tank (5), the injection tank (7), and the water replenishment tank (6) is greater than the sum of the volumes of the water collection well (8) and the reactor enclosure (9); The water collection well (8) is located at the rear side wall of the reactor compartment (2) and close to the stern, so as to ensure that condensed water is effectively collected when the ship is in a stern-heeled state; The suction port B (52) extends into the water collecting well (8), is connected to the nozzle (25) on the top of the reactor compartment (2) through a connecting pipeline, a branch line is drawn from the connecting pipeline and extends into the pressure suppression water tank (3), a valve A (31) is provided on the branch line, and a suction port A (51) is provided at the end of the branch line; a spray pump (21) and a valve B (32) are provided on the connecting pipeline and behind the branch point; The suction port C (53) extends into the water collecting well (8) and is connected to the low-pressure injection pump (22) and the valve H (39) through a connecting pipeline. A valve E (35) is provided on the connecting pipeline.

2. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: The low-pressure injection pump (22) and valve H (39) are provided in two sets in parallel; The high-pressure injection pump (23) and valve D (34) are provided in two sets in parallel.

3. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: A vent pipe A (54) and a vent pipe B (55) connected to the reactor compartment (2) are respectively provided on the top of the water injection tank (7) and the water supplement tank (6) to balance the pressure inside and outside the liquid compartment.

4. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: The water injection tank (7) and the water replenishment tank (6) are two separate water tanks or an integral water tank.

5. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: The height of the reactor enclosure (9) is higher than the height of the core (12), so as to ensure that the core (12) can be submerged when water accumulates in the reactor enclosure (9).

6. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: Panel flat irons (10) are arranged on the top and middle area of ​​the wall panels of the reactor enclosure (9) to prevent the wall panels of the reactor enclosure (9) from buckling.

7. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: The spray heads (25) are arranged at equal intervals on the top of the reactor compartment (2) in a spray ring or matrix arrangement.

8. A marine reactor suppression and injection system as claimed in claim 1, characterized in that: If the space of the suppression water tank (3), the safety injection tank (5), the water injection tank (7) and the make-up water tank (6) is insufficient, the space is expanded toward the isolation void compartment (4) according to actual needs to adjust the volume of the suppression water tank (3), the safety injection tank (5), the water injection tank (7) and the make-up water tank (6), and to ensure that the total volume of the suppression water tank (3), the safety injection tank (5), the water injection tank (7) and the make-up water tank (6) does not exceed the total volume of the cavity between the containment (1) and the reactor compartment (2).

9. A marine reactor suppression and injection system according to any one of claims 1 to 8, characterized in that: When the reactor coolant pressure boundary is damaged due to a small breach, resulting in a loss of coolant accident, the reactor coolant system pressure and water level slowly decrease, the valve C (33) is opened, and the cooling water in the water injection tank (7) is injected into the core (12) in the reactor (11) through the connecting pipeline, the valve C (33), the high-pressure injection pump (23), the valve D (34), and the valve K (42); When a large groove loss of coolant accident occurs, the reactor coolant system pressure drops below the injection tank pressure, and the cooling water in the injection tank (5) is injected into the reactor (11) through the connecting pipeline, the normally open valve F (36), the check valve (37), and the valve K (42), and floods the core (12) in the reactor (11) in a short time to prevent the core (12) from melting; When the pressure continues to drop to the threshold value, the valve G (38) is opened, and the cooling water in the water injection tank (7) is injected into the core (12) through the connecting pipeline, the valve G (38), the low-pressure injection pump (22), the valve H (39), the valve I (40), and the valve K (42); After the low-pressure safety injection operation has been in progress for a long period of time, the pressure and temperature in the reactor coolant system and the reactor (11) cabin have been reduced and are in a relatively stable state, or when the water injection tank (7) is emptied, the operator switches to the recirculation cooling stage according to the situation, opens valve E (35) to switch the low-pressure safety injection pump (22) to suck the liquid in the water collection well (8) through the suction port C (53), opens valve J (41) to re-inject the liquid into the core (12) after cooling by the circulation cooler (24), and performs recirculation operation to continuously cool the core (12).

10. A marine reactor suppression and injection system according to any one of claims 1 to 8, characterized in that: When a loss of coolant accident occurs in the primary circuit of the reactor or a main steam pipe rupture accident occurs in the reactor compartment, and the pressure in the reactor compartment rises to a certain threshold, the reactor compartment heat removal system is automatically activated, the valve A (31) is opened, the spray pump (21) is started, and the water in the pressure suppression water tank (3) is sprayed into the reactor compartment through the suction port A (51), the valve A (31), the spray pump (21), the valve B (32), and the spray head (25), so as to reduce the pressure and temperature of the reactor compartment; When the pressure and temperature of the reactor coolant system are reduced to a relatively stable operating condition, or the water source of the pressure suppression water tank (3) is emptied and the system enters the intermittent operation recirculation cooling stage, the condensed water after the reactor compartment is cooled is collected in the water collection well (8), and under the action of the spray pump (21), it returns to the spray head (25) through the suction port B (52) and the corresponding connecting pipeline to continue spraying.

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