WO2022166184A1 - Système et procédé d'échange de chaleur hélium-dioxyde de carbone - Google Patents

Système et procédé d'échange de chaleur hélium-dioxyde de carbone Download PDF

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Publication number
WO2022166184A1
WO2022166184A1 PCT/CN2021/115628 CN2021115628W WO2022166184A1 WO 2022166184 A1 WO2022166184 A1 WO 2022166184A1 CN 2021115628 W CN2021115628 W CN 2021115628W WO 2022166184 A1 WO2022166184 A1 WO 2022166184A1
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WO
WIPO (PCT)
Prior art keywords
carbon dioxide
helium
outlet
inlet
header
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Application number
PCT/CN2021/115628
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English (en)
Chinese (zh)
Inventor
马晓珑
李红智
梁法光
韩传高
姚明宇
张瑞祥
姚尧
刘俊峰
李康
余俨
常重喜
叶林
彭伟超
徐校飞
于德
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西安热工研究院有限公司
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Application filed by 西安热工研究院有限公司 filed Critical 西安热工研究院有限公司
Publication of WO2022166184A1 publication Critical patent/WO2022166184A1/fr

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D15/00—Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
    • F01D15/10—Adaptations for driving, or combinations with, electric generators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D17/00—Regulating or controlling by varying flow
    • F01D17/10—Final actuators
    • F01D17/12—Final actuators arranged in stator parts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K25/00—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
    • F01K25/08—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours
    • F01K25/10—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours the vapours being cold, e.g. ammonia, carbon dioxide, ether
    • F01K25/103—Carbon dioxide
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K7/00—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating
    • F01K7/32—Steam engine plants characterised by the use of specific types of engine; Plants or engines characterised by their use of special steam systems, cycles or processes; Control means specially adapted for such systems, cycles or processes; Use of withdrawn or exhaust steam for feed-water heating the engines using steam of critical or overcritical pressure
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21D—NUCLEAR POWER PLANT
    • G21D1/00—Details of nuclear power plant
    • G21D1/02—Arrangements of auxiliary equipment
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin

Definitions

  • the invention belongs to the technical field of nuclear power, and in particular relates to a system and method for exchanging helium-carbon dioxide heat.
  • the heat generated by the nuclear fuel in the primary circuit of the high temperature gas-cooled reactor demonstration power station is transferred to the water in the secondary circuit through the helium-water shell-and-tube spiral heat exchanger (through-flow evaporator) and its system.
  • the system has the following problems:
  • the evaporator heat exchange tube is 14MPa, 570°C steam, the heat exchange tube is 7MPa, 750°C helium with radioactive graphite dust, and the heat exchange tube is It is very dangerous after leakage during operation.
  • the unit After the accidental shutdown, the unit needs to cool down for a long time before the water circulation can be established again, which affects the availability and economy of the unit.
  • the purpose of the present invention is to provide a system and method for exchanging helium-carbon dioxide heat against the deficiencies of the prior art.
  • the present invention adopts the following technical solutions to realize:
  • a helium-carbon dioxide heat exchange system comprising a helium-carbon dioxide heat exchanger, a helium inlet header, a helium outlet header, a carbon dioxide inlet header and a carbon dioxide outlet header;
  • the outlet of the helium inlet header is connected to the first inlet of the helium-carbon dioxide heat exchanger, the first outlet of the helium-carbon dioxide heat exchanger is connected to the inlet of the helium outlet header, and the outlet of the carbon dioxide inlet header is connected to the helium-
  • the second inlet of the carbon dioxide heat exchanger and the second outlet of the helium-carbon dioxide heat exchanger are connected to the inlet of the carbon dioxide outlet header.
  • a further improvement of the present invention is that the helium gas inlet header is equipped with a filter screen that can be cleaned and removed, and is equipped with a differential pressure monitoring device to monitor the differential pressure of the filter screen.
  • a further improvement of the present invention is that the carbon dioxide inlet header is equipped with a cleanable and detachable filter screen, and a differential pressure monitoring device is equipped to monitor the differential pressure of the filter screen, and the helium-carbon dioxide heat exchanger is a plate heat exchanger.
  • a further improvement of the present invention is that it also includes a main helium blower, a reactor pressure vessel inlet pipeline and a reactor pressure vessel; wherein,
  • the outlet of the helium outlet header is connected to the inlet of the main helium blower, the outlet of the helium blower is connected to the inlet of the inlet pipe of the reactor pressure vessel, the outlet of the inlet pipe of the reactor pressure vessel is connected to the inlet of the reactor pressure vessel, and the outlet of the reactor pressure vessel is connected to the inlet of the reactor pressure vessel.
  • the outlet of the reactor pressure vessel outlet pipe is connected to the inlet of the helium gas inlet header.
  • a further improvement of the present invention is that it also includes a pressure carbon dioxide turbine outlet pipe valve group, a compressor, a carbon dioxide turbine inlet pipe valve group and a carbon dioxide turbine; wherein,
  • the outlet of the carbon dioxide outlet header is connected to the inlet of the carbon dioxide turbine inlet pipe valve group, the outlet of the carbon dioxide turbine inlet pipe valve group is connected to the carbon dioxide turbine inlet, and the carbon dioxide turbine outlet is connected to the carbon dioxide turbine outlet pipe valve group.
  • Inlet, the outlet of the carbon dioxide turbine outlet pipe valve group is connected to the inlet of the compressor, and the outlet of the compressor is connected to the inlet of the carbon dioxide inlet header.
  • a further improvement of the present invention is that a check valve is included in the valve group of the carbon dioxide turbine outlet pipe.
  • a further improvement of the present invention is that an isolation valve and a regulating valve are included in the carbon dioxide turbine inlet pipe valve group.
  • a method for exchanging helium-carbon dioxide heat is based on the system for exchanging helium-carbon dioxide heat, comprising the following steps:
  • the helium-carbon dioxide heat exchanger is connected to the system after the other equipment of the helium-carbon dioxide heat exchange system is connected and cleaned;
  • the carbon dioxide system is composed of a carbon dioxide turbine outlet pipe valve group, a compressor, a carbon dioxide inlet header, a carbon dioxide side of the helium-carbon dioxide heat exchanger, a carbon dioxide outlet header, a carbon dioxide turbine inlet pipe valve group, and a carbon dioxide turbine. Filled with carbon dioxide gas, powered by the compressor to establish a carbon dioxide cycle;
  • the helium system consists of the reactor pressure vessel, the reactor pressure vessel outlet pipe, the helium inlet header, the helium side of the helium-carbon dioxide heat exchanger, the helium outlet header, the main helium blower, and the reactor pressure vessel inlet pipe.
  • the gas system is filled with helium, and the main helium blower provides power to establish a helium cycle;
  • the temperature of the helium gas increases after absorbing heat in the reactor pressure vessel, and the heat is transferred to the carbon dioxide in the carbon dioxide system through the helium gas circulation in the helium-carbon dioxide heat exchanger to complete the heat exchange of helium-carbon dioxide;
  • a further improvement of the present invention is that during the operation of the helium-carbon dioxide heat exchange system, the differential pressure of the filter screen in the helium inlet header is monitored, and when the differential pressure of the filter screen is high, the filter screen is pulled out for cleaning.
  • a further improvement of the present invention is that during the operation of the helium-carbon dioxide heat exchange system, the differential pressure of the filter screen in the carbon dioxide inlet header is monitored, and when the differential pressure of the filter screen is high, the filter screen is drawn out for cleaning.
  • the present invention at least has the following beneficial technical effects:
  • a filter screen is set in the inlet header of the helium gas system of the helium-carbon dioxide heat exchanger, which can filter and reduce the dust carried in the helium gas in the primary circuit, and improve the safety of the unit operation;
  • the helium-carbon dioxide heat exchanger adopts a plate heat exchanger, the structure of the heat exchanger is stable, and there is no flow-induced vibration;
  • the main helium fan is set outside the helium-carbon dioxide heat exchanger, which is conducive to troubleshooting;
  • the first and second circuit heat exchangers are gas-gas (helium-supercritical carbon dioxide) heat exchangers, which avoids dry and wet state conversion, and avoids start-stop and operation.
  • the two-phase flow in the process is unstable, and the problem of flow-induced vibration of the heat exchanger is largely avoided from the mechanism;
  • the supercritical carbon dioxide power generation cycle has a more significant efficiency advantage under the condition of high temperature parameters. It is more in line with the positioning of the high temperature gas-cooled reactor. At the 666°C level, the net efficiency can be increased by 3-5 points in the water working medium circulation, and at the 766°C level, the net efficiency can be increased by 6-8 points in the water working medium circulation.
  • FIG. 1 is a structural block diagram of a helium-carbon dioxide heat exchange system according to the present invention.
  • Helium-CO2 heat exchanger 2. Helium inlet header, 3. Reactor pressure vessel outlet pipe, 4. Helium outlet header, 5. Main helium blower, 6. Reactor pressure vessel inlet pipe, 7. Carbon dioxide Inlet header, 8. Carbon dioxide turbine outlet pipe valve group, 9. Carbon dioxide outlet header, 10. Carbon dioxide turbine inlet pipe valve group, 11. Compressor, 12. Reactor pressure vessel, 13. Carbon dioxide turbine.
  • a helium-carbon dioxide heat exchange system includes a helium-carbon dioxide heat exchanger 1, a helium gas inlet header 2, a helium gas outlet header 4, a main helium blower 5, a reactor pressure Vessel inlet pipe 6 , carbon dioxide inlet header 7 , carbon dioxide turbine outlet pipe valve group 8 , carbon dioxide outlet header 9 , carbon dioxide turbine inlet pipe valve group 10 , compressor 11 , reactor pressure vessel 12 and carbon dioxide turbine 13 .
  • the outlet of the helium inlet header 2 is connected to the first inlet of the helium-carbon dioxide heat exchanger 1, the first outlet of the helium-carbon dioxide heat exchanger 1 is connected to the inlet of the helium outlet header 4, and the carbon dioxide inlet header
  • the outlet of 7 is connected to the second inlet of the helium-carbon dioxide heat exchanger 1 , and the second outlet of the helium-carbon dioxide heat exchanger 1 is connected to the inlet of the carbon dioxide outlet header 9 .
  • the outlet of the helium outlet header 4 is connected to the inlet of the main helium blower 5, the outlet of the helium blower 5 is connected to the inlet of the reactor pressure vessel inlet pipe 6, and the outlet of the reactor pressure vessel inlet pipe 6 is connected to the inlet of the reactor pressure vessel 12,
  • the outlet of the reactor pressure vessel 12 is connected to the inlet of the reactor pressure vessel outlet pipe 3 , and the outlet of the reactor pressure vessel outlet pipe 3 is connected to the inlet of the helium gas inlet header 2 .
  • the outlet of the carbon dioxide outlet header 9 is connected to the inlet of the carbon dioxide turbine inlet pipe valve group 10, the outlet of the carbon dioxide turbine inlet pipe valve group 10 is connected to the inlet of the carbon dioxide turbine 13, and the outlet of the carbon dioxide turbine 13 is connected to the carbon dioxide turbine.
  • the inlet of the outlet pipe valve group 8, the outlet of the carbon dioxide turbine outlet pipe valve group 8 is connected to the inlet of the compressor 11, and the outlet of the compressor 11 is connected to the inlet of the carbon dioxide inlet header 7.
  • the helium gas inlet header 2 is equipped with a filter screen that can be cleaned and removed, and is equipped with a differential pressure monitoring device to monitor the differential pressure of the filter screen.
  • the carbon dioxide inlet header 7 is equipped with a cleanable and detachable filter screen, and is equipped with a differential pressure monitoring device to monitor the differential pressure of the filter screen.
  • the helium-carbon dioxide heat exchanger 1 is a plate heat exchanger.
  • a check valve is included in the carbon dioxide turbine outlet pipe valve group 8 .
  • the carbon dioxide turbine inlet pipe valve group 10 includes an isolation valve and a regulating valve.
  • a method for exchanging helium-carbon dioxide heat provided by the present invention comprises the following steps:
  • the helium-carbon dioxide heat exchanger 1 is connected to the system after the other equipment of the helium-carbon dioxide heat exchange system is connected and cleaned;
  • Reactor pressure vessel 12 reactor pressure vessel outlet pipe 3, helium inlet header 2, helium side of helium-carbon dioxide heat exchanger 1, helium outlet header 4, main helium blower 5, reactor pressure vessel inlet pipe 6
  • a helium gas system is formed, and helium gas is filled in the helium gas system, and the main helium blower 5 provides power to establish a helium gas cycle;
  • the temperature of the helium gas is increased after absorbing heat in the reactor pressure vessel 12, and the heat is transferred to the carbon dioxide in the carbon dioxide system in the helium-carbon dioxide heat exchanger 1 through the helium gas circulation to complete the heat exchange of the helium-carbon dioxide;
  • the differential pressure of the filter screen in the helium gas inlet header 2 is monitored, and when the differential pressure of the filter screen is high, the filter screen is pulled out for cleaning.
  • the differential pressure of the filter screen in the carbon dioxide inlet header 7 is monitored, and when the differential pressure of the filter screen is high, the filter screen is pulled out for cleaning.
  • the high-temperature gas-cooled reactor carbon dioxide power generation system adopts a "helium-carbon dioxide" plate heat exchanger, which is simpler in structure, easier to manufacture, and has better operation safety and reliability than the spiral tube direct-current evaporator used in the current high-temperature gas-cooled reactor water vapor power generation system.
  • the secondary loop uses carbon dioxide as the medium for swiping the turbine, there is no phase change, no "steam-water separator", start-stop system, no condenser, condensate system, and circulating water system; no chemical water production required system, water dosing system; finishing system.
  • High-temperature gas-cooled reactor carbon dioxide power generation system The higher-temperature gas-cooled reactor water vapor power generation system greatly simplifies the system.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Combustion & Propulsion (AREA)
  • Plasma & Fusion (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Carbon And Carbon Compounds (AREA)

Abstract

L'invention concerne un système d'échange de chaleur hélium-dioxyde de carbone. Le système comprend un échangeur de chaleur hélium-dioxyde de carbone (1), un collecteur d'entrée d'hélium (2), un collecteur de sortie d'hélium (4), un collecteur d'entrée de dioxyde de carbone (7) et un collecteur de sortie de dioxyde de carbone (9), une sortie du collecteur d'entrée d'hélium (2) étant reliée à une première entrée de l'échangeur de chaleur hélium-dioxyde de carbone (1), une première sortie de l'échangeur de chaleur hélium-dioxyde de carbone (1) étant reliée à une entrée du collecteur de sortie d'hélium (4), une sortie du collecteur d'entrée de dioxyde de carbone (7) étant reliée à une seconde entrée de l'échangeur de chaleur hélium-dioxyde de carbone (1), et une seconde sortie de l'échangeur de chaleur hélium-dioxyde de carbone (1) étant reliée à une entrée du collecteur de sortie de dioxyde de carbone (9). L'invention concerne en outre un procédé d'échange de chaleur hélium-dioxyde de carbone. Lors de la mise en œuvre du procédé, aucun changement de phase n'est provoqué dans la plage de conditions de fonctionnement complète d'un cycle de génération d'énergie de dioxyde de carbone supercritique, ce qui permet d'éviter la conversion entre des états humides et secs, évitant les problèmes d'instabilité d'écoulement d'un flux à deux phases lors des processus de démarrage-arrêt et de mise en œuvre, etc., et d'éviter dans une large mesure le problème de vibration induite par l'écoulement d'un échangeur de chaleur à partir d'un mécanisme.
PCT/CN2021/115628 2021-02-07 2021-08-31 Système et procédé d'échange de chaleur hélium-dioxyde de carbone WO2022166184A1 (fr)

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CN202110179627.8 2021-02-07
CN202110179627.8A CN112814748A (zh) 2021-02-07 2021-02-07 一种氦-二氧化碳热量交换的系统和方法

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Publication number Priority date Publication date Assignee Title
CN112814748A (zh) * 2021-02-07 2021-05-18 西安热工研究院有限公司 一种氦-二氧化碳热量交换的系统和方法
CN115263477B (zh) * 2022-08-03 2024-05-07 西安热工研究院有限公司 耦合储能和布雷顿循环的气冷微堆能量转换系统及方法

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CN103232836A (zh) * 2013-05-07 2013-08-07 中国科学院近代物理研究所 热交换介质、热交换系统及核反应堆系统
CN103867242A (zh) * 2013-02-28 2014-06-18 摩尔动力(北京)技术股份有限公司 超低温热源发动机
CN104126102A (zh) * 2012-02-02 2014-10-29 黑利福卡斯有限公司 流体导管系统
CN109026243A (zh) * 2018-09-17 2018-12-18 刘彦 能量转换系统
CN112814748A (zh) * 2021-02-07 2021-05-18 西安热工研究院有限公司 一种氦-二氧化碳热量交换的系统和方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102326261A (zh) * 2009-01-19 2012-01-18 曳达研究和发展有限公司 太阳能联合循环电力系统
CN104126102A (zh) * 2012-02-02 2014-10-29 黑利福卡斯有限公司 流体导管系统
CN103867242A (zh) * 2013-02-28 2014-06-18 摩尔动力(北京)技术股份有限公司 超低温热源发动机
CN103232836A (zh) * 2013-05-07 2013-08-07 中国科学院近代物理研究所 热交换介质、热交换系统及核反应堆系统
CN109026243A (zh) * 2018-09-17 2018-12-18 刘彦 能量转换系统
CN112814748A (zh) * 2021-02-07 2021-05-18 西安热工研究院有限公司 一种氦-二氧化碳热量交换的系统和方法

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