CN214752966U - Pressurized water reactor secondary side waste heat discharge system - Google Patents

Pressurized water reactor secondary side waste heat discharge system Download PDF

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CN214752966U
CN214752966U CN202121237782.2U CN202121237782U CN214752966U CN 214752966 U CN214752966 U CN 214752966U CN 202121237782 U CN202121237782 U CN 202121237782U CN 214752966 U CN214752966 U CN 214752966U
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water
outlet end
tank
inlet end
pressure
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胡凌生
郑俊铭
赵光辉
张亚婷
羊本林
卢放
赵鑫樾
陈石
胡龙翔
王子冠
张晓杰
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Hualong International Nuclear Power Technology Co Ltd
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Hualong International Nuclear Power Technology Co Ltd
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    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
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Abstract

The utility model provides a pressurized water reactor secondary side waste heat discharge system, include: steam generator, moisturizing case and high-pressure gas provide the device, wherein: the high-pressure gas supply device is used for supplying high-pressure gas; the first inlet end of the water replenishing tank is connected with the high-pressure gas supply device, and the first outlet end of the water replenishing tank is connected with the first inlet end of the steam generator. The embodiment of the utility model provides a provide the device through increasing moisturizing case and high-pressure gas, replenished the inside water of steam generator behind the unusual accident that takes place, make the system be used for the water of evaporation sufficient, improved the cooling step-down effect of pressurized water reactor secondary side.

Description

Pressurized water reactor secondary side waste heat discharge system
Technical Field
The utility model relates to a nuclear power technical field, concretely relates to pressurized water reactor secondary side waste heat discharge system.
Background
The secondary side of a large pressurized water reactor is an important component of a nuclear power plant system. When a small breach of the pressurized water reactor is abnormal, the secondary side of the pressurized water reactor is required to discharge heat so as to reduce the temperature and the pressure. In the prior art, stored water inside the secondary side of a pressurized water reactor is generally evaporated to take away waste heat. However, since the stored water in the secondary side of the pressurized water reactor is used when the system works normally, the stored water is less, and the evaporation, temperature reduction and pressure reduction effects are poor in abnormal accidents.
Therefore, the problem that the temperature and pressure reduction effect of the secondary side of the medium-pressure water reactor in an abnormal accident is poor exists in the related technology.
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides a pressurized water reactor secondary side waste heat discharge system to the relatively poor problem of cooling step-down effect of pressurized water reactor secondary side in the unusual accident that exists among the solution prior art.
In order to achieve the above object, an embodiment of the present invention provides a pressurized water reactor secondary side waste heat removal system, including: steam generator, moisturizing case and high-pressure gas provide the device, wherein:
the high-pressure gas supply device is used for supplying high-pressure gas;
the first inlet end of the water replenishing tank is connected with the high-pressure gas supply device, and the first outlet end of the water replenishing tank is connected with the first inlet end of the steam generator.
Optionally, the pressurized water reactor secondary side waste heat removal system further comprises a deaerator, and the deaerator is connected with the second inlet end of the water replenishing tank.
Optionally, the first inlet end of the water replenishing tank is connected with the high-pressure gas supply device sequentially through a first check valve and a first electric isolation valve;
the second inlet end of the water replenishing tank is connected with the deaerator through a second check valve and a second electric isolation valve in sequence;
and a first outlet end of the water replenishing tank is connected with a first inlet end of the evaporator through a third check valve and a third electric isolating valve in sequence.
Optionally, the pressurized water reactor secondary side waste heat removal system further includes a first differential pressure measurement meter and a second differential pressure measurement meter, wherein an inlet end of the first differential pressure measurement meter is connected to a second outlet end of the water replenishing tank, and an outlet end of the first differential pressure measurement meter is connected to a third inlet end of the water replenishing tank;
the inlet end of the second differential pressure measuring meter is connected with the third outlet end of the water replenishing tank, and the outlet end of the second differential pressure measuring meter is connected with the fourth inlet end of the water replenishing tank;
and the third inlet end and the fourth inlet end of the water replenishing tank are positioned on one side of the water replenishing tank close to the first outlet end, and the second outlet end and the third outlet end of the water replenishing tank are positioned on one side of the water replenishing tank far away from the first outlet end.
Optionally, the pressurized water reactor secondary side waste heat removal system further comprises a first pressure release valve and two sets of pressure gauges, the first pressure release valve and the two sets of pressure gauges are respectively connected with a fourth outlet end of the water replenishing tank, and the fourth outlet end of the water replenishing tank is located on one side far away from the first outlet end of the water replenishing tank.
Optionally, the first outlet end of the steam generator is connected to a second pressure relief valve.
Optionally, a second inlet end of the steam generator is connected to the nuclear power plant water supply system through a first valve, and a second outlet end of the steam generator is connected to the nuclear power plant steam system through a second valve.
One of the above technical solutions has the following advantages or beneficial effects:
the embodiment of the utility model provides an in, provide the device through increasing moisturizing case and high-pressure gas, replenished the inside water of steam generator behind the unusual accident that takes place, make the system be used for the water of evaporation sufficient, improved the effect of pressurized-water reactor secondary side cooling step-down in the unusual accident.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.
Fig. 1 is a simple schematic diagram of a pressurized water reactor secondary side waste heat removal system according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a pressurized water reactor secondary side waste heat removal system according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
As shown in fig. 1, an embodiment of the present invention provides a pressurized water reactor secondary side waste heat removal system, including: a steam generator 11, a makeup tank 12, and a high-pressure gas supply device 13, wherein:
the high-pressure gas supply device 13 is used for supplying high-pressure gas;
the first inlet end of the water replenishing tank 12 is connected with a high-pressure gas supply device 13, and the first outlet end of the water replenishing tank 12 is connected with the first inlet end of the steam generator 11.
In the embodiment, the water replenishing tank 12 and the high-pressure gas supply device 13 are added, so that the steam generator 11 can provide sufficient water for cooling and depressurization when an abnormal small opening occurs, and the secondary side waste heat discharge effect of the pressurized water reactor is optimized.
Specifically, when an abnormally small opening is generated in the steam generator 11, the heat of the system needs to be changed into steam by evaporating the water into steam and discharged to the atmosphere, so that the pressure on the primary side is reduced to a pressure condition that enables operation. The water used in the prior art is derived from water remaining inside the steam generator 11, and conditions may occur in which the pressure in the steam generator 11 is not reduced to a usable pressure after the water is used up. At this time, the water replenishing tank 12 and the high-pressure gas supply device 13 are added, and water in the water replenishing tank 12 is extruded and conveyed to the steam generator 11 through the high-pressure gas to be supplemented, so that the pressure of the system can be reduced to a usable condition, and the overall cooling and pressure reducing effect is improved.
Wherein, the high-pressure gas that high-pressure gas supply device 13 provided can satisfy when moisturizing case and steam generating device are on same horizontal position, and high-pressure gas can carry the inside water extrusion of moisturizing case to steam generator in. Generally, a high-pressure gas having a pressure of 4.0MPa to 5.0MPa is used. The embodiment of the utility model provides a high-pressure nitrogen gas that nuclear island nitrogen gas distribution system in the adoption nuclear power plant provided, its magnitude of pressure is 4.2MPa, and the water that carries moisturizing case 12 through 4.2 MPa's high-pressure nitrogen gas as the high-pressure gas extrusion gets into steam generator 11.
Wherein, the water replenishing tank 12 can be arranged at a lower position through the high-pressure gas supply device 13, and the installation and implementation difficulty of the whole system is reduced.
In addition, the makeup tank 12 may be sized to accommodate the needs of the nuclear power plant. If the volume of the make-up water tank 12 is large enough, the waste heat can be completely discharged out of the system and can be conducted for a long time, and the use of an auxiliary water supply system in the prior art can be replaced. Nuclear power plants typically use a makeup tank 12 in conjunction with a steam generator 11 to improve safety.
Optionally, as shown in fig. 2, the pressurized water reactor secondary side waste heat removal system further includes a deaerator 14, and the deaerator 14 is connected to the second inlet end of the makeup water tank 12.
In this embodiment, the deaerator 14 is used to provide water to supplement the water in the makeup water tank 12, so as to realize water recycling in the nuclear power plant.
Wherein, the water pressure of moisturizing case 12 constantly reduces in the in-process of using, and the water pressure in oxygen-eliminating device 14 is greater than the inside water pressure of moisturizing case 12, and water enters the inside of moisturizing case 12 along with pressure differential.
Optionally, the first inlet end of the water replenishing tank 12 is connected to the high-pressure gas supply device 13 sequentially through the first check valve 101 and the first electric isolation valve 102;
the second inlet end of the water replenishing tank 12 is connected with the deaerator 14 through a second check valve 103 and a second electric isolation valve 104 in sequence;
a first outlet end of the makeup tank 12 is connected to a first inlet end of the evaporator through a third check valve 105 and a third electrically operated isolation valve 106 in this order.
In the embodiment, the passive use of the whole system is realized, the operation of personnel on the whole system is facilitated, and the use efficiency of the system is improved.
Specifically, the first electric isolation valve 102, the second electric isolation valve 104, and the third electric isolation valve 106 are pressure-sensitive, and when the pressures on the two sides are not consistent, the first electric isolation valve 102, the second electric isolation valve 104, or the third electric isolation valve 106 is automatically opened, and when the pressures on the two sides are consistent, the first electric isolation valve, the second electric isolation valve, or the third electric isolation valve is kept closed. In the using process of the system, the water pressure in the steam generator 11 becomes small, water inside the water replenishing tank 12 enters the steam generator 11 through the third check valve 105 and the third electric isolation valve 106, meanwhile, water inside the deaerator 14 enters the water replenishing tank 12 through the second electric isolation valve 104 and the second check valve 103, and high-pressure gas enters the water replenishing tank 12 through the first electric isolation valve 102 and the first check valve 101 and maintains a certain pressure.
Wherein the refill tank 12 needs to be pre-filled with a volume of water and pressurized with nitrogen before the refill tank 12 is used for the first time. An operator manually opens the second electrically-operated isolating valve 104 to input a certain amount of water into the makeup water tank 12, and usually 70% -80% of the water can be pre-filled according to the power of the pressurized water reactor. After pre-filling the water, the second electrically-operated isolation valve 104 is closed, and the first electrically-operated isolation valve 102 is opened to pressurize the gas inside the refill tank 12 until the desired set point is reached, the current pressure being 4.2MPa of high pressure nitrogen.
In addition, according to the safety requirements in the nuclear power plant, the water supply tank 12, a pipeline connecting the first outlet end of the water supply tank 12 with the steam generator 11, a third check valve 105, a third electric isolation valve 106, a pipeline between the water supply tank 12 and the second electric isolation valve 104, a second check valve 103, a pipeline between the water supply tank 12 and the first electric isolation valve 102, and a first check valve 101 belong to safety level 1/barrier level 2, and the design specification is RCC-M2(RCC is "design and construction rules of pressurized water reactor nuclear island mechanical equipment", RCC-M2 is the safety level 2 design specification in RCC, and so on); the second electrically powered isolation valve 104, the line between the second electrically powered isolation valve 104 and the deaerator 14, the line between the first electrically powered isolation valve 102 and the high pressure gas supply 13, and the first electrically powered isolation valve 102 are of safety class 3/barrier class 2, design specification RCC-M3.
Optionally, the pressurized water reactor secondary-side waste heat removal system further includes a first differential pressure measuring meter 15 and a second differential pressure measuring meter 16, wherein an inlet end of the first differential pressure measuring meter 15 is connected to a second outlet end of the makeup water tank 12, and an outlet end of the first differential pressure measuring meter 15 is connected to a third inlet end of the makeup water tank 12;
the inlet end of the second differential pressure measuring meter 16 is connected with the third outlet end of the water replenishing tank 12, and the outlet end of the second differential pressure measuring meter is connected with the fourth inlet end of the water replenishing tank 12;
the third inlet end and the fourth inlet end of the makeup water tank 12 are located on one side of the makeup water tank 12 close to the first outlet end, and the second outlet end and the third outlet end of the makeup water tank 12 are located on one side of the makeup water tank 12 far away from the first outlet end.
In the present embodiment, the pressure difference inside the refill tank 12 is measured by the first differential pressure gauge 15 and the second differential pressure gauge 16, and the amount of water inside the refill tank 12 is estimated.
The first differential pressure measuring meter 15 and the second differential pressure measuring meter 16 are connected to prevent the water quantity inside the water replenishing tank 12 from being misjudged by a vehicle after a certain differential pressure measuring meter is damaged.
In addition, according to the safety requirements in the nuclear power plant, the first differential pressure measuring meter 15, the second differential pressure measuring meter 16, the pipeline between the first differential pressure measuring meter 15 and the water replenishing tank 12, and the pipeline between the second differential pressure measuring meter 16 and the water replenishing tank 12 belong to safety level 1/barrier level 2, and the design specification level is RCC-M2.
Optionally, the pressurized water reactor secondary-side waste heat removal system further includes a first pressure release valve 18 and two sets of pressure gauges 17, the first pressure release valve 18 and the two sets of pressure gauges 17 are respectively connected to a fourth outlet end of the water replenishing tank 12, and the fourth outlet end of the water replenishing tank 12 is located on one side far away from the first outlet end of the water replenishing tank 12.
In this embodiment, the two sets of pressure gauges 17 and the first pressure relief valve 18 can control the pressure inside the water replenishing tank 12 to be maintained within a fixed range, so that the personnel can conveniently check and maintain the pressure at regular intervals.
The design of the two groups of pressure gauges 17 is similar to the design purpose of the first differential pressure measuring gauge 15 and the second differential pressure measuring gauge 16, and the error processing of maintenance personnel caused by the misjudgment of a certain pressure gauge when the pressure gauge fails is avoided.
In addition, a first pressure relief valve 18 is used in conjunction with two sets of pressure gauges 17. Firstly, two groups of pressure gauges 17 are set with a threshold value, which is usually 5.0MPa, and when the pressure in the water replenishing tank 12 exceeds the set threshold value, the first pressure release valve 18 is opened to release redundant nitrogen, so that unnecessary damage to the water replenishing tank 12 due to overlarge internal pressure is avoided.
In addition, according to the safety requirements in the nuclear power plant, the two groups of pressure gauges 17, the pipelines between the two groups of pressure gauges 17 and the water replenishing tank 12 and the first pressure relief valve 18 belong to safety level 1/barrier level 2, and the design specification level is RCC-M2.
Optionally, a second pressure relief valve 19 is connected to the first outlet port of the steam generator 11.
In the present embodiment, the second relief valve 19 releases the steam from the inside of the steam generator 11 to the outside, thereby reducing the pressure and temperature inside the steam generator 11.
Wherein, the internal pressure of the steam generator 11 in the normal use process is about 6.7MPa, the second pressure release valve 19 is opened by the operator after the occurrence of an abnormal accident, the water inside the steam generator 11 is vaporized into steam to reduce the temperature and the pressure, and when the pressure of the steam generator 11 is reduced to below 4.2MPa, the water inside the water replenishing tank 12 enters the steam generator 11 through the third check valve 105 and the third electric isolating valve 106 to replenish the water. Energy control is not needed in the whole process, and passive operation is realized.
In addition, the second pressure relief valve 19 belongs to safety class 1/barrier class 2, with a design code level of RCC-M2, according to the safety requirements in the nuclear power plant.
Optionally, the second inlet end of the steam generator 11 is connected to the nuclear power plant feedwater system through a first valve 107, and the second outlet end of the steam generator 11 is connected to the nuclear power plant steam system through a second valve 108.
In the embodiment, the connection or disconnection of the secondary side waste heat discharge system of the pressurized water reactor is controlled by the first valve 107 and the second valve 108.
In a normal working state, the first valve 107 and the second valve 108 are opened, and the second pressure relief valve 19 is closed; after an abnormal accident, the first valve 107 and the second valve 108 are closed, the second relief valve 19 is opened, and the passive operation of the system reduces the pressure and the temperature in the steam generator 11 to a safe range.
In addition, according to the safety requirements of the nuclear power plant, the first valve 107, the second valve 108, the pipeline between the first valve 107 and the steam generator 11, and the pipeline between the second valve 108 and the steam generator 11 all belong to safety class 1/barrier class 2, and the design specification level is RCC-M2.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, which are only illustrative and not restrictive, and those skilled in the art can make many forms without departing from the spirit and scope of the present invention.

Claims (7)

1. A pressurized water reactor secondary side waste heat removal system is characterized by comprising: steam generator, moisturizing case and high-pressure gas provide the device, wherein:
the high-pressure gas supply device is used for supplying high-pressure gas;
the first inlet end of the water replenishing tank is connected with the high-pressure gas supply device, and the first outlet end of the water replenishing tank is connected with the first inlet end of the steam generator.
2. The pressurized water reactor secondary side waste heat removal system of claim 1, further comprising a deaerator connected to the second inlet end of the makeup tank.
3. The pressurized water reactor secondary side waste heat removal system as claimed in claim 2, wherein the first inlet end of the water supply tank is connected with the high-pressure gas supply device sequentially through a first check valve and a first electric isolation valve;
the second inlet end of the water replenishing tank is connected with the deaerator through a second check valve and a second electric isolation valve in sequence;
and the first outlet end of the water replenishing tank is connected with the first inlet end of the steam generator sequentially through a third check valve and a third electric isolating valve.
4. The pressurized water reactor secondary side waste heat removal system of claim 1, further comprising a first differential pressure measurement gauge and a second differential pressure measurement gauge, wherein an inlet end of the first differential pressure measurement gauge is connected with a second outlet end of the makeup water tank, and an outlet end of the first differential pressure measurement gauge is connected with a third inlet end of the makeup water tank;
the inlet end of the second differential pressure measuring meter is connected with the third outlet end of the water replenishing tank, and the outlet end of the second differential pressure measuring meter is connected with the fourth inlet end of the water replenishing tank;
and the third inlet end and the fourth inlet end of the water replenishing tank are positioned on one side of the water replenishing tank close to the first outlet end, and the second outlet end and the third outlet end of the water replenishing tank are positioned on one side of the water replenishing tank far away from the first outlet end.
5. The pressurized water reactor secondary side waste heat removal system of claim 1, further comprising a first pressure relief valve and two sets of pressure gauges, wherein the first pressure relief valve and the two sets of pressure gauges are respectively connected to a fourth outlet end of the makeup water tank, and the fourth outlet end of the makeup water tank is located on a side away from the first outlet end of the makeup water tank.
6. The secondary side waste heat removal system of a pressurized water reactor according to claim 1, wherein the first outlet end of the steam generator is connected with a second pressure relief valve.
7. The secondary side waste heat removal system of the pressurized water reactor as claimed in claim 1, wherein a second inlet end of the steam generator is connected with a nuclear power plant water supply system through a first valve, and a second outlet end of the steam generator is connected with a nuclear power plant steam system through a second valve.
CN202121237782.2U 2021-06-03 2021-06-03 Pressurized water reactor secondary side waste heat discharge system Active CN214752966U (en)

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CN202121237782.2U CN214752966U (en) 2021-06-03 2021-06-03 Pressurized water reactor secondary side waste heat discharge system

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Application Number Priority Date Filing Date Title
CN202121237782.2U CN214752966U (en) 2021-06-03 2021-06-03 Pressurized water reactor secondary side waste heat discharge system

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CN214752966U true CN214752966U (en) 2021-11-16

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