阅读说明：本技术 模块化多用途小型氟盐冷却高温堆能量系统 (Modularized multipurpose small-sized villaumite cooling high-temperature reactor energy system ) 是由 张大林 姜殿强 李新宇 闵鑫 王成龙 田文喜 秋穗正 苏光辉 于 2021-08-30 设计创作，主要内容包括：本发明公开了模块化多用途小型氟盐冷却高温堆能量系统：包括反应堆本体系统、非能动余热排出系统、紧凑型超临界二氧化碳布雷顿循环系统、二回路系统和综合利用型超临界二氧化碳布雷顿循环系统；反应堆核燃料采用TRISO+石墨基体材料和螺旋十字型式,可以提高传热性能及固有安全性；紧凑型超临界二氧化碳布雷顿循环系统热效率超过48％,可以应用于空间有限的场所；综合利用型超临界二氧化碳布雷顿循环热效率超过54％,可以应用于资源丰富的场所；本发明既能实现能量的高效紧凑利用,也能满足能源多用途、一体化的生产、储存和转化需求。(The invention discloses a modular multipurpose small-sized villaumite cooling high-temperature reactor energy system which comprises: the system comprises a reactor body system, a passive residual heat removal system, a compact supercritical carbon dioxide Brayton cycle system, a two-loop system and a comprehensive utilization supercritical carbon dioxide Brayton cycle system; the reactor nuclear fuel adopts a TRISO + graphite base material and a spiral cross type, so that the heat transfer performance and the inherent safety can be improved; the heat efficiency of the compact supercritical carbon dioxide Brayton cycle system exceeds 48 percent, and the system can be applied to places with limited space; the comprehensive utilization type supercritical carbon dioxide Brayton cycle thermal efficiency exceeds 54 percent, and can be applied to places with rich resources; the invention can realize the high-efficiency compact utilization of energy and can also meet the requirements of multipurpose and integrated production, storage and conversion of energy.)

1. The modular multipurpose small-sized villaumite cooling high-temperature reactor energy system is characterized in that: the system comprises a reactor body system (1), a passive residual heat removal system (2), a compact supercritical carbon dioxide Brayton cycle system (3), a secondary loop system (4) and a comprehensive utilization supercritical carbon dioxide Brayton cycle system (5);

the reactor body system (1) is used as a heat source of a modular multipurpose small-sized villaumite cooling high-temperature reactor energy system and comprises a reactor vessel (1-1), wherein a reactor core active area (1-2), a reactor control rod and a driving mechanism (1-3) thereof, and a FLiBe-CO are arranged in the reactor vessel (1-1)₂The reactor comprises main heat exchangers (1-4), FLiBe-FLiNaK main heat exchangers (1-5), first FLiBe-FLiNaK waste heat discharging heat exchangers (1-6), second FLiBe-FLiNaK waste heat discharging heat exchangers (1-7), first axial flow main pumps (1-8), second axial flow main pumps (1-9), reactor core surrounding cylinders (1-10), radial reflecting layers (1-11) andan axially reflective layer (1-12); FLiBe-CO₂The main heat exchanger (1-4), the FLiBe-FLiNaK main heat exchanger (1-5), the first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6) and the second FLiBe-FLiNaK waste heat discharge heat exchanger (1-7) are positioned at the upper part in the reactor container (1-1), and the FLiBe-CO₂The lower parts of the main heat exchangers (1-4) and the FLiBe-FLiNaK main heat exchangers (1-5) are respectively provided with first axial flow pumps (1-8) and first axial flow pumps (1-9); the control rod and the driving mechanism (1-3) are arranged at the upper part of the reactor core active area (1-2); the reactor core surrounding barrels (1-10) are arranged outside the radial reflecting layers, the radial reflecting layers (1-11) are arranged in the circumferential direction of the reactor core active area, and the axial reflecting layers (1-12) are arranged on the upper portion and the lower portion of the reactor core active area;

the working flow of the reactor body system (1) is as follows: when the reactor body system (1) normally operates, coolant is driven by a first axial flow pump (1-8) and a second axial flow pump (1-9), enters a reactor core active area (1-2) from the bottom of a reactor vessel (1-1), flows upwards through the reactor core active area (1-2), absorbs heat, is deflected downwards, is discharged out of a heat exchanger (1-6) through first FLiBe-FLiNaK waste heat and discharged out of a heat exchanger (1-7) through second FLiBe-FLiNaK waste heat, and finally enters the first axial flow pump (1-8) and the second axial flow pump (1-9) to be pressurized to complete the circulation of the coolant in the reactor core;

the passive residual heat removal system (2) is used as a special safety facility of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system, shares a first FLiBe-FLiNaK residual heat removal heat exchanger (1-6) and a second FLiBe-FLiNaK residual heat removal heat exchanger (1-7) with the reactor body system (1), and further comprises an air cooling tower (2-3), a first air heat exchanger (2-1) and a second air heat exchanger (2-2) which are arranged in the air cooling tower (2-3), and a connecting pipeline and a valve; an outlet of the first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6) is connected with an inlet of the first air heat exchanger (2-1), and an outlet of the first air heat exchanger (2-1) is connected with an inlet of the first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6); an outlet of the second FLiBe-FLiNaK waste heat discharge heat exchanger (1-7) is connected with an inlet of the second air heat exchanger (2-2), and an outlet of the second air heat exchanger (2-2) is connected with an inlet of the second FLiBe-FLiNaK waste heat discharge heat exchanger (1-7);

the passive residual heat removal system (2) has the following working process: under the working conditions of reactor shutdown and accidents, the FLiNaK salt is heated by a first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6) and then is driven by buoyancy to enter a first air heat exchanger (2-1), and then the FLiNaK salt is cooled by air and flows out of the first air heat exchanger (2-1) and enters the first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6) to complete natural circulation; the second FLiBe-FLiNaK waste heat discharge heat exchanger (1-7) and the second air heat exchanger (2-2) have the same working process as the first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6) and the first air heat exchanger (2-1);

the compact supercritical carbon dioxide Brayton cycle system (3) is used as an energy conversion module of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system and shares FLiBe-CO with the reactor body system (1)₂The heat exchanger comprises a main heat exchanger (1-4), a first turbine (3-1), a first high-temperature heat regenerator (3-2), a first low-temperature heat regenerator (3-3), a first flow dividing valve (3-4), a first cold-end heat exchanger (3-5), a first main compressor (3-6), a first auxiliary compressor (3-7), a first flow combining valve (3-8) and connecting pipelines and valves; first FLiNaK-CO₂An outlet of the heat exchanger (1-4) is connected with an inlet of a first turbine (3-1), an outlet of the first turbine (3-1) is connected with a hot side inlet of a first high-temperature regenerator (3-2), a hot side outlet of the first high-temperature regenerator (3-2) is connected with a hot side inlet of a first low-temperature regenerator (3-3), a hot side outlet of the first low-temperature regenerator (3-3) is connected with a first splitter valve inlet (3.1), a first splitter valve first outlet (3.2) is connected with a first auxiliary compressor (3-7) inlet, and a first auxiliary compressor (3-7) outlet is connected with a first merging valve first inlet (3.4); a second outlet (3.3) of the first diversion valve is connected with an inlet of a first cold-end heat exchanger (3-5), an outlet of the first cold-end heat exchanger (3-5) is connected with an inlet of a first main compressor (3-6), an outlet of the first main compressor (3-6) is connected with a cold-side inlet of the first low-temperature heat regenerator (3-3), and a cold-side outlet of the first low-temperature heat regenerator (3-3) is connected with a second inlet (3.5) of the first confluence valve; the outlet (3.6) of the first confluence valve is connected with the cold side inlet of the first high-temperature regenerator (3-2), and the cold side outlet of the first high-temperature regenerator (3-2) is connected with the first FLiBe-CO₂Inlets of the main heat exchangers (1-4) are connected;

the compact supercritical carbon dioxide Brayton cycle system (3) has the following working process: in the first FLiNaK-CO₂In the heat exchanger (1-4), CO₂Heated by the main coolant saltEnters the first turbine (3-1) to do work, then enters the hot side of the first high-temperature regenerator (3-2) to release heat, and CO leaving the hot side of the first high-temperature regenerator (3-2)₂The heat enters the hot side of the first low-temperature regenerator (3-3) to continue releasing heat, and is split by a first splitter valve (3-4): a part of CO₂Enters a first auxiliary compressor (3-7), is compressed and then enters a first converging valve (3-8); another part of CO₂After being cooled by a first cold end heat exchanger (3-5), the gas is compressed by a first main compressor (3-6), then enters a first converging valve (3-8) after absorbing heat in a first low temperature heat regenerator (3-3), and CO from the first low temperature heat regenerator (3-3) and a first auxiliary compressor (3-7)₂The flow is converged at the first flow-converging valve (3-8), and enters the first FLiBe-CO after the heat absorption of the first high-temperature heat regenerator (3-2)₂The main heat exchanger (1-4) is heated again to form a cycle;

the two-loop system (4) is used as an intermediate heat exchange and energy storage system of a modularized multipurpose small-sized villiaumite cooling high-temperature reactor energy system and provides heat energy for a comprehensive utilization type supercritical carbon dioxide Brayton cycle system (5), the two-loop system (4) and the reactor body system (1) share a FLiBe-FLiNaK main heat exchanger (1-5), the two-loop molten salt system further comprises a two-loop molten salt pump (4-1) and a molten salt pool (4-2), and a high-temperature process heat interface (4-3), a first FLiNaK-CO are arranged in the molten salt pool (4-2)₂Heat exchanger (5-1), second FLiNaK-CO₂Heat exchanger (5-2), third FLiNaK-CO₂The heat exchanger (5-3) and the connecting pipeline and the valve; an outlet of the FLiBe-FLiNaK main heat exchanger (1-5) is connected with an inlet of a molten salt pool (4-2), an outlet of the molten salt pool (4-2) is connected with an inlet of a two-loop molten salt pump (4-1), and an outlet of the two-loop molten salt pump (4-1) is connected with an inlet of the FLiBe-FLiNaK main heat exchanger (1-5);

the working process of the two-loop system (4) is as follows: the FLiNaK salt is heated in a FLiBe-FLiNaK main heat exchanger (1-5) and then enters a molten salt pool (4-2), and in the molten salt pool (4-2), the high-temperature FLiNaK salt outputs high-temperature heat to the outside through a high-temperature process thermal interface (4-3), and the heat is used for high-temperature hydrogen production, mineral exploitation and molten salt energy storage; first FLiNaK-CO₂Heat exchanger (5-1), second FLiNaK-CO₂Heat exchanger (5-2) and third FLiNaK-CO₂The heat exchanger (5-3) absorbs the heat of the molten salt pool (4-2) to heat CO₂After the FLiNaK salt releases heat in the molten salt pool (4-2), the FLiNaK salt is melted by two loopsThe salt pump (4-1) is pressurized and then enters a FLiBe-FLiNaK main heat exchanger (1-5) to form circulation;

the comprehensive utilization type supercritical carbon dioxide Brayton cycle system (5) is used as an energy conversion module of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system and shares the first FLiNaK-CO with a molten salt pool (4-2) of the two-loop system (4)₂Heat exchanger (5-1), second FLiNaK-CO₂Heat exchanger (5-2) and third FLiNaK-CO₂The heat exchanger (5-3) further comprises a second turbine (5-4), a third turbine (5-5), a fourth turbine (5-6), a second low-temperature heat regenerator (5-7), a first medium-temperature heat regenerator (5-8), a second high-temperature heat regenerator (5-9), a second auxiliary compressor (5-10), a second main compressor (5-11), a third main compressor (5-12), a second cold-end heat exchanger (5-13), a third cold-end heat exchanger (5-14), a second flow dividing valve (5-15), a second flow merging valve (5-16), a third flow dividing valve (5-17), a third flow merging valve (5-18) and connecting pipelines and valves; the first outlet (5.2) of the second shunt valve is connected with the cold side inlet of a second high-temperature regenerator (5-9), and the cold side outlet of the second high-temperature regenerator (5-9) is connected with a second FLiNaK-CO₂The inlet of the heat exchanger (5-2) is connected with the second FLiNaK-CO₂The outlet of the heat exchanger (5-2) is connected with the inlet of a first turbine (5-4), and the outlet of the first turbine (5-4) is connected with a third FLiNaK-CO₂The inlet (5-3) of the heat exchanger is connected, and the third FLiNaK-CO is connected₂The outlet of the heat exchanger is connected with the inlet of a second turbine (5-5), the outlet of the second turbine (5-5) is connected with the hot side inlet of a second high-temperature regenerator (5-9), and the hot side outlet of the second high-temperature regenerator (5-9) is connected with the first inlet (5.4) of a second confluence valve; a second outlet (5.3) of the second flow dividing valve and the first FLiNaK-CO₂The inlet of the heat exchanger (5-1) is connected with the first FLiNaK-CO₂The outlet of the heat exchanger (5-1) is connected with the inlet of a fourth turbine (5-6), and the outlet of the fourth turbine (5-6) is connected with a second inlet (5.5) of the second confluence valve; the outlet (5.6) of the second confluence valve is connected with the hot side inlet of the first medium-temperature regenerator (5-8), the hot side outlet of the first medium-temperature regenerator (5-8) is connected with the hot side inlet of the second low-temperature regenerator (5-7), the hot side outlet of the second low-temperature regenerator (5-7) is connected with the inlet (5.7) of the third confluence valve, the first outlet (5.8) of the third confluence valve is connected with the inlet of the second auxiliary compressor (5-10), the outlet of the second auxiliary compressor (5-10) is connected with the first inlet (5.10) of the third confluence valveConnecting; a second outlet (5.9) of the third split valve is connected with an inlet of a second cold-end heat exchanger (5-13), an outlet of the second cold-end heat exchanger (5-13) is connected with an inlet of a second main compressor (5-11), an outlet of the second main compressor (5-11) is connected with an inlet of a third cold-end heat exchanger (5-14), an outlet of the third cold-end heat exchanger (5-14) is connected with an inlet of a third main compressor (5-12), an outlet of the third main compressor (5-12) is connected with a cold-side inlet of a second low-temperature regenerator (5-7), and a cold-side outlet of the second low-temperature regenerator (5-7) is connected with a second inlet (5.11) of a third confluence valve; the outlet (5.12) of the third confluence valve is connected with the cold side inlet of the first medium temperature heat regenerator (5-8), and the cold side outlet of the first medium temperature heat regenerator (5-8) is connected with the inlet (5.1) of the second shunt valve;

the comprehensive utilization type supercritical carbon dioxide Brayton cycle system (5) has the following working process: by CO₂Splitting at a second splitting valve (5-15): a part of CO from the cold side of the first medium temperature regenerator (5-8)₂Enters a cold side of a second high-temperature regenerator (5-9) for absorbing heat and then enters a second FLiNaK-CO₂The heat exchanger (5-2) is heated and enters a second turbine (5-4) to do work, and the CO after doing work₂Into the third FLiNaK-CO₂Heated in the heat exchanger (5-3), then enters a third turbine (5-5) to do work, and CO after doing work again₂Enters the hot side of a second high-temperature regenerator (5-9) to release heat; another part of CO from the cold side of the first medium temperature regenerator (5-8)₂Into the first FLiNaK-CO₂After absorbing heat in the heat exchanger (5-1), the heat enters a fourth turbine (5-6) to do work; CO from the hot side of the fourth turbine (5-5) and the second high temperature regenerator (5-9)₂After confluence of the second confluence valve (5-16), the mixed gas enters a first medium-temperature regenerator (5-8) for heat release at the hot side, then enters a first medium-temperature regenerator (5-7) for heat release at the hot side, and then is split by a third split valve (5-17): a part of CO2 is compressed and boosted by a second auxiliary compressor (5-10); another part of CO₂After being cooled by a second cold end heat exchanger (5-13), the refrigerant enters a second main compressor (5-11) for compression and pressure boosting, then enters a third cold end heat exchanger (5-14), and enters a third main compressor (5-12) again for compression and pressure boosting after being cooled; two strands of CO₂Converged by a third flow merging valve (5-18), enters a cold side of a first medium temperature heat regenerator (5-8) for absorbing heat and then enters a second flow dividing valve (5-15) to form circulation。

2. The modular multi-purpose small fluoride salt cooled high temperature stack energy system of claim 1, further comprising: the reactor core active area (1-2) of the reactor body system (1) has the thermal power of 125MW, the reactor core inlet temperature of 650 ℃, the reactor core outlet temperature of 700 ℃, and FLiBe salt serving as a coolant, LiF and BeF₂The mole numbers are 67% and 33% respectively; the passive residual heat removal system (2) and the secondary loop system (4) adopt FLiNaK salt as a cooling working medium, and the mole fractions of LiF, NaF and KF are 46.5%, 11.5% and 42% respectively.

3. The modular multi-purpose small fluoride salt cooled high temperature stack energy system of claim 1, further comprising: the reactor core active area (1-2) of the reactor body system (1) adopts a spiral cross-shaped fuel element, and the TRISO nuclear fuel is dispersed in a matrix at a filling rate of 50%; nuclear fuel²³⁵The U enrichment degrees are respectively 15% and 17.5%; the fuel rods in the single component are arranged in a triangular shape, and the components are arranged in a triangular shape.

4. The modular multi-purpose small fluoride salt cooled high temperature stack energy system of claim 1, further comprising: FLiBe-CO of reactor body system (1)₂A main heat exchanger (1-4), a first FLiNaK-CO of a comprehensive utilization type supercritical carbon dioxide Brayton cycle system (5)₂Heat exchanger (5-1), second FLiNaK-CO₂Heat exchanger (5-2) and third FLiNaK-CO₂The heat exchangers (5-3) are all printed circuit board type heat exchangers; the main FLiBe-FLiNaK heat exchanger (1-5) of the reactor body system (1), the first FLiBe-FLiNaK waste heat discharge heat exchanger (1-6) and the second FLiBe-FLiNaK waste heat discharge heat exchanger (1-7) of the passive waste heat discharge system (2) are all shell-and-tube heat exchangers.

5. The modular multi-purpose small fluoride salt cooled high temperature stack energy system of claim 1, further comprising: the thermal efficiency of the compact supercritical carbon dioxide Brayton cycle system (3) exceeds 48 percent, and the thermal efficiency of the comprehensive utilization supercritical carbon dioxide Brayton cycle system (5) exceeds 54 percent.

6. The modular multi-purpose small fluoride salt cooled high temperature stack energy system of claim 1, further comprising: the reactor vessel (1-1) of the reactor body system (1) has a diameter of less than 3.5 meters and a height of less than 3 meters.

7. The modular multi-purpose small fluoride salt cooled high temperature stack energy system of claim 1, further comprising: the energy conversion system consisting of the compact supercritical carbon dioxide Brayton cycle system (3), the two-loop system (4) and the comprehensive utilization supercritical carbon dioxide Brayton cycle system (5) is not put into use at the same time, and the systems are switched according to requirements.

Technical Field

The invention relates to the technical field of advanced nuclear energy development and energy comprehensive utilization, in particular to a modular multipurpose small-sized villaumite cooling high-temperature reactor energy system.

Background

Western regions of China, particularly inland deep in regions along the new silk road, wide regions and abundant resources, and provides sufficient strategic convolution space and deep national defense safety barriers; however, the area is remote and has complex climate conditions, and the energy demand is characterized by diversification and scatter. Therefore, a set of safe and efficient multipurpose and integrated energy supply scheme is provided, and is an urgent need for promoting economic development and national defense construction in western regions.

The villiaumite cooled high-temperature reactor integrates the advantages of a fourth-generation advanced nuclear reactor such as a molten salt reactor, a high-temperature gas cooled reactor and a sodium cooled fast reactor, has the characteristics of high-temperature low-pressure operation, no water cooling, inherent safety, compact structure and the like, is suitable for being built into a small modularized villiaumite cooled high-temperature reactor with small volume, light weight and low cost, and can realize high-efficiency power generation in water-deficient areas; meanwhile, the energy-saving building is suitable for being built underground, has good concealment, can provide an integrated energy solution for national defense bases, and improves the vitality and the fighting capacity of the energy-saving building. In addition, the reactor can output high-temperature process heat above 700 ℃, and is used for high-temperature hydrogen production, brine desalination, mineral reserve exploitation and the like.

In recent years, domestic preliminary research work on modular small-sized fluorine salt cooled high-temperature reactors is steadily carried out, but no detailed general plan and technical route exists at present in consideration of the design and configuration of a series of systems such as multipurpose energy supply modes, energy storage/conversion and comprehensive utilization systems, special passive waste heat discharge systems and the like. Therefore, from the application level of capacity, energy storage, conversion and utilization of the modular small-sized villiaumite cooled high-temperature reactor to the design and cooperative operation level of the reactor body, the energy storage system and the energy conversion system, a set of complete system configuration and technical scheme is needed to support the design and construction of a multipurpose and integrated energy scheme system, so as to further assist the new silk path strategy and promote the economic development and national defense construction of western remote areas.

Disclosure of Invention

To overcome the above problems of the prior art, it is an object of the present invention to provide a modular multipurpose small-sized villiaumite cooled high temperature reactor energy system, including a highly compact solution and a comprehensive utilization solution. The two schemes can realize reactor miniaturization, modularization, water-free cooling and high-efficiency power generation, wherein the comprehensive utilization scheme can output high-temperature process heat above 700 ℃, can realize energy multistage utilization and storage, and can also be used for high-temperature hydrogen production, mineral deposit exploitation and the like.

In order to achieve the purpose, the invention adopts the following technical scheme:

the modularized multipurpose small-sized villaumite cooling high-temperature reactor energy system comprises a reactor body system 1, a passive waste heat discharge system 2, a compact supercritical carbon dioxide Brayton cycle system 3, a two-loop system 4 and a comprehensive utilization supercritical carbon dioxide Brayton cycle system 5;

the reactor body system 1 is used as a heat source of a modular multipurpose small-sized villaumite cooling high-temperature reactor energy system and comprises a reactor vessel 1-1, wherein a reactor core active area 1-2, a reactor control rod and a driving mechanism 1-3 thereof, and a FLiBe-CO are arranged in the reactor vessel 1-1₂The system comprises main heat exchangers 1-4, a FLiBe-FLiNaK main heat exchanger 1-5, a first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6, a second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7, a first axial flow main pump 1-8, a second axial flow main pump 1-9, a reactor core surrounding cylinder 1-10, a radial-radial main pumpA retro-reflective layer 1-11 and an axial reflective layer 1-12; FLiBe-CO₂The main heat exchanger 1-4, the FLiBe-FLiNaK main heat exchanger 1-5, the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and the second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 are positioned at the upper part in the reactor container 1-1, and are positioned at the upper part in the reactor container 1-1₂The lower parts of the main heat exchangers 1-4 and the FLiBe-FLiNaK main heat exchangers 1-5 are respectively provided with first axial flow pumps 1-8 and first axial flow pumps 1-9; the control rod and drive mechanism 1-3 is arranged on the upper part of the reactor core active area 1-2; the reactor core surrounding barrels 1-10 are arranged outside the radial reflecting layers, the radial reflecting layers 1-11 are arranged in the circumferential direction of the reactor core active area, and the axial reflecting layers 1-12 are arranged on the upper portion and the lower portion of the reactor core active area;

the working flow of the reactor body system 1 is as follows: when the reactor body system 1 normally operates, coolant is driven by a first axial flow pump 1-8 and a second axial flow pump 1-9, enters a reactor core active area 1-2 from the bottom of a reactor vessel 1-1, flows upwards through the reactor core active area 1-2 to absorb heat, is deflected downwards, passes through a first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and a second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 to release heat, and finally enters the first axial flow pump 1-8 and the second axial flow pump 1-9 to be pressurized to complete the circulation of the coolant in the reactor core;

the passive residual heat removal system 2 is used as a special safety facility of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system, shares a first FLiBe-FLiNaK residual heat removal heat exchanger 1-6 and a second FLiBe-FLiNaK residual heat removal heat exchanger 1-7 with the reactor body system 1, and further comprises an air cooling tower 2-3, a first air heat exchanger 2-1 and a second air heat exchanger 2-2 which are arranged in the air cooling tower 2-3, and a connecting pipeline and a valve; an outlet of the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 is connected with an inlet of the first air heat exchanger 2-1, and an outlet of the first air heat exchanger 2-1 is connected with an inlet of the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6;

the passive residual heat removal system 2 has the following working process: under the working conditions of reactor shutdown and accidents, the FLiNaK salt is discharged from the heat exchanger 1-6 by the first FLiBe-FLiNaK waste heat, is heated and then is driven to enter the first air heat exchanger 2-1 by buoyancy, then is cooled by air and flows out of the first air heat exchanger 2-1, enters the first FLiBe-FLiNaK waste heat and is discharged from the heat exchanger 1-6, and natural circulation is completed; the second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 and the second air heat exchanger 2-2 have the same connection mode and working flow as the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and the first air heat exchanger 2-1;

the compact supercritical carbon dioxide Brayton cycle system 3 is used as an energy conversion module of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system and shares FLiBe-CO with the reactor body system 1₂The main heat exchanger 1-4 further comprises a first turbine 3-1, a first high-temperature heat regenerator 3-2, a first low-temperature heat regenerator 3-3, a first flow dividing valve 3-4, a first cold-end heat exchanger 3-5, a first main compressor 3-6, a first auxiliary compressor 3-7, a first flow merging valve 3-8, and connecting pipelines and valves; first FLiNaK-CO₂An outlet of a heat exchanger 1-4 is connected with an inlet of a first turbine 3-1, an outlet of the first turbine 3-1 is connected with a hot side inlet of a first high-temperature heat regenerator 3-2, a hot side outlet of the first high-temperature heat regenerator 3-2 is connected with a hot side inlet of a first low-temperature heat regenerator 3-3, a hot side outlet of the first low-temperature heat regenerator 3-3 is connected with a first splitter valve inlet 3.1, a first splitter valve first outlet 3.2 is connected with an inlet of a first auxiliary compressor 3-7, and a first auxiliary compressor 3-7 outlet is connected with a first merging valve first inlet 3.4; a second outlet 3.3 of the first diversion valve is connected with an inlet of a first cold-end heat exchanger 3-5, an outlet of the first cold-end heat exchanger 3-5 is connected with an inlet of a first main compressor 3-6, an outlet of the first main compressor 3-6 is connected with a cold-side inlet of a first low-temperature heat regenerator 3-3, and a cold-side outlet of the first low-temperature heat regenerator 3-3 is connected with a second inlet 3.5 of the first confluence valve; the outlet 3.6 of the first confluence valve is connected with the cold side inlet of the first high-temperature heat regenerator 3-2, and the cold side outlet of the first high-temperature heat regenerator 3-2 is connected with the first FLiBe-CO₂Inlets of the main heat exchangers 1-4 are connected;

the compact supercritical carbon dioxide brayton cycle system 3 has the following working process: in the first FLiNaK-CO₂In heat exchanger 1-4, CO₂The CO enters a first turbine 3-1 to do work after being heated by main coolant salt, then enters a hot side of a first high-temperature regenerator 3-2 to release heat, and the CO leaving the hot side of the first high-temperature regenerator 3-2₂And the heat enters the hot side of the first low-temperature heat regenerator 3-3 to continue to release heat, and is split by the first splitter valve 3-4: a part of CO₂The gas enters a first auxiliary compressor 3-7, is compressed and then enters a first flow merging valve 3-8;another part of CO₂After being cooled by a first cold end heat exchanger 3-5, the gas is compressed by a first main compressor 3-6, then enters a first converging valve 3-8 after absorbing heat in a first low temperature heat regenerator 3-3, and CO from the first low temperature heat regenerator 3-3 and a first auxiliary compressor 3-7₂Converging in a first converging valve 3-8, absorbing heat by a first high-temperature heat regenerator 3-2, and then entering a first FLiBe-CO₂The main heat exchanger 1-4 is heated again to form a cycle;

the two-loop system 4 is used as an intermediate heat exchange and energy storage system of a modularized multipurpose small-sized villiaumite cooling high-temperature reactor energy system and provides heat energy for a comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5, the two-loop system 4 and the reactor body system 1 share a FLiBe-FLiNaK main heat exchanger 1-5, the two-loop molten salt system further comprises a two-loop molten salt pump 4-1 and a molten salt pool 4-2, and a high-temperature process thermal interface 4-3 and a first FLiNaK-CO are arranged in the molten salt pool 4-2₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2, third FLiNaK-CO₂The heat exchanger 5-3 and a connecting pipeline and a valve; an outlet of the FLiBe-FLiNaK main heat exchanger 1-5 is connected with an inlet of a molten salt pool 4-2, an outlet of the molten salt pool 4-2 is connected with an inlet of a two-loop molten salt pump 4-1, and an outlet of the two-loop molten salt pump 4-1 is connected with an inlet of the FLiBe-FLiNaK main heat exchanger 1-5;

the working process of the two-loop system 4 is as follows: the FLiNaK salt is heated in a FLiBe-FLiNaK main heat exchanger 1-5 and then enters a molten salt pool 4-2, in the molten salt pool 4-2, the high-temperature FLiNaK salt outputs high-temperature heat to the outside through a high-temperature process heat interface 4-3, and the heat is used for high-temperature hydrogen production, mineral deposit exploitation and molten salt energy storage; first FLiNaK-CO₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2 and third FLiNaK-CO₂The heat exchanger 5-3 absorbs the heat of the molten salt pool 4-2 to heat CO₂After the FLiNaK salt releases heat in the molten salt pool 4-2, the FLiNaK salt enters the FLiBe-FLiNaK main heat exchanger 1-5 after being pressurized by the two-loop molten salt pump 4-1 to form circulation;

the comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5 is used as an energy conversion module of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system and shares the first FLiNaK-CO with the molten salt pool 4-2 of the two-loop system 4₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2 and third FLiNaK-CO₂The heat exchanger 5-3 further comprises a second turbine 5-4, a third turbine 5-5, a fourth turbine 5-6, a second low-temperature heat regenerator 5-7, a first medium-temperature heat regenerator 5-8, a second high-temperature heat regenerator 5-9, a second auxiliary compressor 5-10, a second main compressor 5-11, a third main compressor 5-12, a second cold-end heat exchanger 5-13, a third cold-end heat exchanger 5-14, a second flow dividing valve 5-15, a second flow combining valve 5-16, a third flow dividing valve 5-17, a third flow combining valve 5-18, and connecting pipelines and valves; the first outlet 5.2 of the second shunt valve is connected with the cold side inlet of a second high-temperature heat regenerator 5-9, and the cold side outlet of the second high-temperature heat regenerator 5-9 is connected with a second FLiNaK-CO₂The inlet of the heat exchanger 5-2 is connected with the second FLiNaK-CO₂The outlet of the heat exchanger 5-2 is connected with the inlet of a first turbine 5-4, the outlet of the first turbine 5-4 is connected with a third FLiNaK-CO₂Inlet 5-3 of the heat exchanger, and a third FLiNaK-CO₂The outlet of the heat exchanger is connected with the inlet of a second turbine 5-5, the outlet of the second turbine 5-5 is connected with the hot side inlet of a second high-temperature regenerator 5-9, and the hot side outlet of the second high-temperature regenerator 5-9 is connected with the first inlet 5.4 of a second confluence valve; second outlet 5.3 of the second splitter valve and the first FLiNaK-CO₂The inlet of the heat exchanger 5-1 is connected with the first FLiNaK-CO₂An outlet of the heat exchanger 5-1 is connected with an inlet of a fourth turbine 5-6, and an outlet of the fourth turbine 5-6 is connected with a second inlet 5.5 of the second confluence valve; the outlet 5.6 of the second merging valve is connected with the hot side inlet of the first medium-temperature heat regenerator 5-8, the outlet of the hot side of the first medium-temperature heat regenerator 5-8 is connected with the hot side inlet of the second low-temperature heat regenerator 5-7, the outlet of the hot side of the second low-temperature heat regenerator 5-7 is connected with the inlet 5.7 of the third merging valve, the first outlet 5.8 of the third merging valve is connected with the inlet 5-10 of the second auxiliary compressor, and the outlet 5-10 of the second auxiliary compressor is connected with the first inlet 5.10 of the third merging valve; a second outlet 5.9 of the third split valve is connected with an inlet of a second cold-end heat exchanger 5-13, an outlet of the second cold-end heat exchanger 5-13 is connected with an inlet of a second main compressor 5-11, an outlet of the second main compressor 5-11 is connected with an inlet of a third cold-end heat exchanger 5-14, an outlet of the third cold-end heat exchanger 5-14 is connected with an inlet of a third main compressor 5-12, an outlet of the third main compressor 5-12 is connected with a cold-side inlet of a second low-temperature heat regenerator 5-7, and a cold-side outlet of the second low-temperature heat regenerator 5-7 is connected with a second inlet 5.11 of a third confluence valve; third merging valve outlet 5.12 and first medium temperature returnA cold side inlet of the heat exchanger 5-8 is connected, and a cold side outlet of the first medium temperature heat regenerator 5-8 is connected with a second diverter valve inlet 5.1;

the comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5 has the following working process: by CO₂Splitting at the second splitting valve 5-15: a portion of CO from the cold side of the first medium temperature regenerator 5-8₂Enters the cold side of a second high-temperature regenerator 5-9 to absorb heat and then enters a second FLiNaK-CO₂The heat exchanger 5-2 is heated and enters a second turbine 5-4 to do work, and CO after doing work₂Into the third FLiNaK-CO₂CO heated in the heat exchanger 5-3 and then enters the third turbine 5-5 to do work and do work again₂Enters the hot side of a second high-temperature heat regenerator 5-9 to release heat; another part of CO from the cold side of the first medium temperature regenerator 5-8₂Into the first FLiNaK-CO₂After absorbing heat in the heat exchanger 5-1, the heat enters a fourth turbine 5-6 to do work; CO from the hot side of the fourth turbine 5-5 and the second high temperature regenerator 5-9₂After confluence of the second confluence valve 5-16, the heat enters a first medium temperature heat regenerator 5-8 for heat release, then enters a first medium temperature heat regenerator 5-7 for heat release, and then is split by a third split valve 5-17: a part of CO2 is compressed and boosted by a second auxiliary compressor 5-10; another part of CO₂After being cooled by a second cold end heat exchanger 5-13, the refrigerant enters a second main compressor 5-11 for compression and pressure boosting, then enters a third cold end heat exchanger 5-14, and enters a third main compressor 5-12 for compression and pressure boosting again after being cooled; two strands of CO₂The mixture flows through the third flow merging valve 5-18, enters the cold side of the first medium temperature heat regenerator 5-8 to absorb heat, and then enters the second flow dividing valve 5-15 to form circulation.

The reactor core active area 1-2 of the reactor body system 1 has the thermal power of 125MW, the reactor core inlet temperature of 650 ℃ and the reactor core outlet temperature of 700 ℃, and FLiBe salt is used as a coolant, LiF and BeF₂The mole numbers are 67% and 33% respectively; the passive residual heat removal system 2 and the secondary loop system 4 adopt FLiNaK salt as a cooling working medium, and the mole fractions of LiF, NaF and KF are 46.5%, 11.5% and 42% respectively.

The reactor core active area 1-2 of the reactor body system 1 adopts a spiral cross-shaped fuel element, and the TRISO nuclear fuel is dispersed in a matrix at a filling rate of 50%; nuclear fuel²³⁵The U enrichment degrees are respectively 15% and 17.5%; the fuel rods in the single component are arranged in a triangular shape, and the components are arranged in a triangular shape.

FLiBe-CO of reactor body system 1₂A main heat exchanger 1-4, a first FLiNaK-CO of a comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2 and third FLiNaK-CO₂The heat exchangers 5-3 are all printed circuit board type heat exchangers; the FLiBe-FLiNaK main heat exchanger 1-5 of the reactor body system 1, the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and the second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 of the passive waste heat discharge system 2 are shell-and-tube heat exchangers.

The thermal efficiency of the compact supercritical carbon dioxide Brayton cycle system 3 exceeds 48%, and the thermal efficiency of the comprehensive utilization supercritical carbon dioxide Brayton cycle system 5 exceeds 54%.

The reactor vessel 1-1 of the reactor body system 1 has a diameter of less than 3.5 meters and a height of less than 3 meters.

The energy conversion system consisting of the compact supercritical carbon dioxide Brayton cycle system 3, the two-loop system 4 and the comprehensive utilization supercritical carbon dioxide Brayton cycle system 5 is not put into use at the same time, and the systems are switched according to requirements.

Compared with the prior art, the invention has the following advantages:

1. the modularized small-sized villaumite cooling high-temperature reactor is combined with a compact supercritical carbon dioxide Brayton circulating system, so that efficient and compact utilization of energy can be realized; the modularized small-sized villaumite cooling high-temperature reactor is combined with a two-loop system and a comprehensive utilization type supercritical carbon dioxide Brayton circulating system, so that the requirements of multipurpose and integrated production, storage and conversion of energy can be met.

2. The reactor adopts FLiBe salt as coolant, has high temperature low pressure, compact structure's advantage. The boiling point of the FLiBe salt is over 1000 ℃, the freezing point is lower than 500 ℃, the operation pressure (minus 0.2MPa) is far lower than that of a pressurized water reactor (15.5MPa) and an air cooled reactor (3-7 MPa), and the probability of primary loop break accidents is effectively reduced; compared with the traditional nuclear reactor coolant, the FLiBe salt heat-carrying performance is higher, the volume heat capacities are respectively 1.16 times, 2.75 times, 4.49 times and 233.5 times of that of water, liquid lead-bismuth alloy, liquid metal sodium and helium, more heat can be taken away under the same coolant volume, and the volume of a reactor vessel is favorably reduced.

3. It is inherently safe. The reactor fuel element adopts a spiral cross type, and the structure of the reactor fuel element can strengthen the heat exchange of the coolant; the TRISO nuclear fuel is dispersed in the graphite matrix, can contain fission gas and fission products, and has the failure temperature higher than 1600 ℃; the passive residual heat removal system is driven by buoyancy and does not need external energy supply.

4. The economy is high. The TRISO nuclear fuel can realize higher burnup depth, thereby improving the fuel utilization rate; the high-temperature process heat of nearly 700 ℃ provided by a molten salt pool in the modularized multipurpose small-sized villiaumite cooling high-temperature reactor system can be used for realizing high-temperature hydrogen production, mineral deposit exploitation, molten salt energy storage and the like.

5. And (4) modularization technology. Most of the devices of the present invention can be manufactured, transported and installed in a modular fashion. By the modular technology, the building time can be shortened, the economy is high, and the application scheme is more flexible.

6. High thermal efficiency, sufficient power and rapid power response. Compared with the traditional Rankine cycle, the supercritical carbon dioxide Brayton cycle system has the advantages of high heat efficiency, compact structure, flexible control, quick response and the like. Through design and calculation, the thermal efficiency of the compact supercritical carbon dioxide Brayton cycle system exceeds 48 percent, and the thermal efficiency of the comprehensive utilization supercritical carbon dioxide Brayton cycle system exceeds 54 percent. The two types of circulation systems can be used for determining whether to invest according to task requirements.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention, including the inlet and outlet of the diverter valve and the flow combining valve;

in the figure:

1: reactor body system

1-1: a reactor vessel; 1-2: a reactor core active region; 1-3: a reactor control rod and a drive mechanism thereof; 1-4: FLiBe-CO₂A primary heat exchanger; 1-5: a FLiBe-FLiNaK main heat exchanger;1-6: the first FLiBe-FLiNaK waste heat is discharged out of the heat exchanger; 1-7: the second FLiBe-FLiNaK waste heat is discharged out of the heat exchanger; 1-8: a first axial flow main pump; 1-9: a first axial flow main pump; 1-10: a core shroud; 1-11: a radially reflective layer; 1-12: axially reflective layer

2: passive residual heat removal system

2-1: a first air heat exchanger; 2-2: a second air heat exchanger; 2-3: air cooling tower

3: a compact supercritical carbon dioxide brayton cycle system;

3-1: a first turbine; 3-2: a first high temperature regenerator; 3-3: a first low temperature regenerator; 3-4: a first diverter valve; 3-5: a first cold side heat exchanger; 3-6: a first main compressor; 3-7: a first auxiliary compressor; 3-8: first flow-merging valve

4: two-loop system

4-1: a second loop molten salt pump; 4-2: a molten salt pool; 4-3: high temperature process thermal interface

5: comprehensive utilization type supercritical carbon dioxide Brayton cycle system

5-1: first FLiNaK-CO₂A heat exchanger; 5-2: second FLiNaK-CO₂A heat exchanger; 5-3: TriFLiNaK-CO₂A heat exchanger; 5-4: a second turbine; 5-5: a third turbine; 5-6: a fourth turbine; 5-7: a second low temperature regenerator; 5-8: a first medium temperature regenerator; 5-9: a second high temperature regenerator; 5-10: a second auxiliary compressor; 5-11: a second main compressor; 5-12: a third main compressor; 5-13: a second cold side heat exchanger; 5-14: a third cold side heat exchanger; 5-15: a second diverter valve; 5-16: a second confluence valve; 5-17: a third diverter valve; 5-18: third flow-merging valve

3-4: a first diverter valve (3.1 is a first diverter valve inlet, 3.2 is a first diverter valve first outlet, 3.3 is a first diverter valve second outlet); 3-8: a first confluence valve (3.4 is a first confluence valve first inlet, 3.5 is a first confluence valve second inlet, and 3.6 is a first confluence valve outlet); 5-15: a second diverter valve (5.1 is a second diverter valve inlet, 5.2 is a second diverter valve first outlet, and 5.3 is a second diverter valve second outlet); 5-16: a second confluence valve (5.4 is a second confluence valve first inlet, 5.5 is a second confluence valve second inlet, and 5.6 is a second confluence valve outlet); 5-17: a third diverter valve (5.7 is a third diverter valve inlet, 5.8 is a third diverter valve first outlet, and 5.9 is a third diverter valve second outlet); 5-18: a third confluence valve (5.10 is a third confluence valve first inlet, 5.11 is a third confluence valve second inlet, and 5.12 is a third confluence valve outlet).

Detailed Description

The present invention provides a modular multi-purpose small-scale villiaumite cooled high temperature reactor energy system, which will now be described in further detail with reference to the accompanying drawings.

As shown in fig. 1, the modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system comprises a reactor body system 1, a passive residual heat removal system 2, a compact supercritical carbon dioxide brayton cycle system 3, a two-loop system 4 and a comprehensive utilization supercritical carbon dioxide brayton cycle system 5;

the reactor body system 1 is used as a heat source of a modularized multipurpose small-sized villiaumite cooling high-temperature reactor energy system and comprises a reactor vessel 1-1, wherein a reactor core active area 1-2, a reactor control rod and a driving mechanism 1-3 thereof, and a FLiBe-CO are arranged in the reactor vessel 1-1₂The device comprises main heat exchangers 1-4, FLiBe-FLiNaK main heat exchangers 1-5, first FLiBe-FLiNaK waste heat discharging heat exchangers 1-6, second FLiBe-FLiNaK waste heat discharging heat exchangers 1-7, first axial flow main pumps 1-8, second axial flow main pumps 1-9, reactor core surrounding cylinders 1-10, radial reflecting layers 1-11 and axial reflecting layers 1-12; FLiBe-CO₂The main heat exchanger 1-4, the FLiBe-FLiNaK main heat exchanger 1-5, the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and the second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 are positioned at the upper part in the reactor container 1-1, and are positioned at the upper part in the reactor container 1-1₂The lower parts of the main heat exchangers 1-4 and the FLiBe-FLiNaK main heat exchangers 1-5 are respectively provided with first axial flow pumps 1-8 and first axial flow pumps 1-9; the control rod and drive mechanism 1-3 is arranged on the upper part of the reactor core active area 1-2; the reactor core surrounding barrels 1-10 are arranged outside the radial reflecting layers, the radial reflecting layers 1-11 are arranged in the circumferential direction of the reactor core active area, and the axial reflecting layers 1-12 are arranged on the upper portion and the lower portion of the reactor core active area;

the reactor body system 1 has the following working procedures: when the reactor body system 1 normally operates, coolant is driven by a first axial flow pump 1-8 and a second axial flow pump 1-9, enters a reactor core active area 1-2 from the bottom of a reactor vessel 1-1, flows upwards through the reactor core active area 1-2 to absorb heat, is deflected downwards, passes through a first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and a second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 to release heat, and finally enters the first axial flow pump 1-8 and the second axial flow pump 1-9 to be pressurized to complete the circulation of the coolant in the reactor core;

the passive residual heat removal system 2 is used as a special safety facility of a modularized multipurpose small-sized villiaumite cooling high-temperature reactor energy system, shares a first FLiBe-FLiNaK residual heat removal heat exchanger 1-6 and a second FLiBe-FLiNaK residual heat removal heat exchanger 1-7 with the reactor body system 1, and other equipment comprises an air cooling tower 2-3, a first air heat exchanger 2-1 and a second air heat exchanger 2-2 which are arranged in the air cooling tower 2-3, a connecting pipeline and a valve and the like; an outlet of the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 is connected with an inlet of the first air heat exchanger 2-1, and an outlet of the first air heat exchanger 2-1 is connected with an inlet of the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6;

the passive residual heat removal system 2 has the following working process: under the working conditions of reactor shutdown and accidents, the FLiNaK salt is discharged from the heat exchanger 1-6 by the first FLiBe-FLiNaK waste heat, is heated and then is driven to enter the first air heat exchanger 2-1 by buoyancy, then is cooled by air and flows out of the first air heat exchanger 2-1, enters the first FLiBe-FLiNaK waste heat and is discharged from the heat exchanger 1-6, and natural circulation is completed; the second FLiBe-FLiNaK waste heat discharge heat exchanger 1-7 and the second air heat exchanger 2-2 have the same connection mode and working flow as the first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and the first air heat exchanger 2-1;

the compact supercritical carbon dioxide Brayton cycle system 3 is used as an energy conversion module of a modular multipurpose small-sized villaumite cooling high-temperature reactor energy system and shares FLiBe-CO with the reactor body system 1₂The system comprises a main heat exchanger 1-4, and other equipment comprises a first turbine 3-1, a first high-temperature heat regenerator 3-2, a first low-temperature heat regenerator 3-3, a first flow dividing valve 3-4, a first cold-end heat exchanger 3-5, a first main compressor 3-6, a first auxiliary compressor 3-7, a first flow combining valve 3-8, connecting pipelines and valves and the like; first FLiNaK-CO₂The outlet of the heat exchanger 1-4 is connected with the inlet of the first turbine 3-1, and the outlet of the first turbine 3-1The first high-temperature heat regenerator 3-2 hot side inlet is connected, the first high-temperature heat regenerator 3-2 hot side outlet is connected with the first low-temperature heat regenerator 3-3 hot side inlet, the first low-temperature heat regenerator 3-3 hot side outlet is connected with the first flow dividing valve inlet 3.1, the first flow dividing valve first outlet 3.2 is connected with the first auxiliary compressor 3-7 inlet, and the first auxiliary compressor 3-7 outlet is connected with the first merging valve first inlet 3.4; a second outlet 3.3 of the first diversion valve is connected with an inlet of a first cold-end heat exchanger 3-5, an outlet of the first cold-end heat exchanger 3-5 is connected with an inlet of a first main compressor 3-6, an outlet of the first main compressor 3-6 is connected with a cold-side inlet of a first low-temperature heat regenerator 3-3, and a cold-side outlet of the first low-temperature heat regenerator 3-3 is connected with a second inlet 3.5 of the first confluence valve; the outlet 3.6 of the first confluence valve is connected with the cold side inlet of the first high-temperature heat regenerator 3-2, and the cold side outlet of the first high-temperature heat regenerator 3-2 is connected with the first FLiBe-CO₂Inlets of the main heat exchangers 1-4 are connected;

the compact supercritical carbon dioxide brayton cycle system 3 has the following working process: in the first FLiNaK-CO₂In heat exchanger 1-4, CO₂The CO enters a first turbine 3-1 to do work after being heated by main coolant salt, then enters a hot side of a first high-temperature regenerator 3-2 to release heat, and the CO leaving the hot side of the first high-temperature regenerator 3-2₂And the heat enters the hot side of the first low-temperature heat regenerator 3-3 to continue to release heat, and is split by the first splitter valve 3-4: a part of CO₂The gas enters a first auxiliary compressor 3-7, is compressed and then enters a first flow merging valve 3-8; another part of CO₂After being cooled by a first cold end heat exchanger 3-5, the gas is compressed by a first main compressor 3-6, then enters a first converging valve 3-8 after absorbing heat in a first low temperature heat regenerator 3-3, and CO from the first low temperature heat regenerator 3-3 and a first auxiliary compressor 3-7₂Converging in a first converging valve 3-8, absorbing heat by a first high-temperature heat regenerator 3-2, and then entering a first FLiBe-CO₂The main heat exchanger 1-4 is heated again to form a cycle;

the two-loop system 4 is used as an intermediate heat exchange and energy storage system of a modularized multipurpose small-sized villiaumite cooling high-temperature reactor energy system, can provide heat energy for a comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5, the two-loop system 4 and the reactor body system 1 share a FLiBe-FLiNaK main heat exchanger 1-5, and other equipment comprises a two-loop molten salt pump 4-1 and a molten salt pool 4-2, a high-temperature process thermal interface 4-3 and a first FLiNaK-CO are arranged in the molten salt pool 4-2₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2, third FLiNaK-CO₂A heat exchanger 5-3, a connecting pipeline, a valve and the like; an outlet of the FLiBe-FLiNaK main heat exchanger 1-5 is connected with an inlet of a molten salt pool 4-2, an outlet of the molten salt pool 4-2 is connected with an inlet of a two-loop molten salt pump 4-1, and an outlet of the two-loop molten salt pump 4-1 is connected with an inlet of the FLiBe-FLiNaK main heat exchanger 1-5;

the working process of the second loop system 4 is as follows: the FLiNaK salt is heated in a FLiBe-FLiNaK main heat exchanger 1-5 and then enters a molten salt pool 4-2, and in the molten salt pool 4-2, the high-temperature FLiNaK salt outputs high-temperature heat to the outside through a high-temperature process heat interface 4-3, and the heat can be used for high-temperature hydrogen production, mineral exploitation, molten salt energy storage and the like; first FLiNaK-CO₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2 and third FLiNaK-CO₂The heat exchanger 5-3 absorbs the heat of the molten salt pool 4-2 to heat CO₂After the FLiNaK salt releases heat in the molten salt pool 4-2, the FLiNaK salt enters the FLiBe-FLiNaK main heat exchanger 1-5 after being pressurized by the two-loop molten salt pump 4-1 to form circulation;

the comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5 serves as an energy conversion module of a modular multipurpose small-sized villiaumite cooling high-temperature reactor energy system and shares a first FLiNaK-CO with a molten salt pool 4-2 of a two-loop system 4₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2 and third FLiNaK-CO₂The heat exchanger 5-3, and other equipment comprises a second turbine 5-4, a third turbine 5-5, a fourth turbine 5-6, a second low-temperature heat regenerator 5-7, a first medium-temperature heat regenerator 5-8, a second high-temperature heat regenerator 5-9, a second auxiliary compressor 5-10, a second main compressor 5-11, a third main compressor 5-12, a second cold-end heat exchanger 5-13, a third cold-end heat exchanger 5-14, a second flow dividing valve 5-15, a second flow combining valve 5-16, a third flow dividing valve 5-17, a third flow combining valve 5-18, connecting pipelines and valves and the like; the first outlet 5.2 of the second shunt valve is connected with the cold side inlet of a second high-temperature heat regenerator 5-9, and the cold side outlet of the second high-temperature heat regenerator 5-9 is connected with a second FLiNaK-CO₂The inlet of the heat exchanger 5-2 is connected with the second FLiNaK-CO₂The outlet of the heat exchanger 5-2 is connected with the inlet of a first turbine 5-4, the outlet of the first turbine 5-4 is connected with a third FLiNaK-CO₂Heat exchangerInlet 5-3, third FLiNaK-CO₂The outlet of the heat exchanger is connected with the inlet of a second turbine 5-5, the outlet of the second turbine 5-5 is connected with the hot side inlet of a second high-temperature regenerator 5-9, and the hot side outlet of the second high-temperature regenerator 5-9 is connected with the first inlet 5.4 of a second confluence valve; second outlet 5.3 of the second splitter valve and the first FLiNaK-CO₂The inlet of the heat exchanger 5-1 is connected with the first FLiNaK-CO₂An outlet of the heat exchanger 5-1 is connected with an inlet of a fourth turbine 5-6, and an outlet of the fourth turbine 5-6 is connected with a second inlet 5.5 of the second confluence valve; the outlet 5.6 of the second merging valve is connected with the hot side inlet of the first medium-temperature heat regenerator 5-8, the outlet of the hot side of the first medium-temperature heat regenerator 5-8 is connected with the hot side inlet of the second low-temperature heat regenerator 5-7, the outlet of the hot side of the second low-temperature heat regenerator 5-7 is connected with the inlet 5.7 of the third merging valve, the first outlet 5.8 of the third merging valve is connected with the inlet 5-10 of the second auxiliary compressor, and the outlet 5-10 of the second auxiliary compressor is connected with the first inlet 5.10 of the third merging valve; a second outlet 5.9 of the third split valve is connected with an inlet of a second cold-end heat exchanger 5-13, an outlet of the second cold-end heat exchanger 5-13 is connected with an inlet of a second main compressor 5-11, an outlet of the second main compressor 5-11 is connected with an inlet of a third cold-end heat exchanger 5-14, an outlet of the third cold-end heat exchanger 5-14 is connected with an inlet of a third main compressor 5-12, an outlet of the third main compressor 5-12 is connected with a cold-side inlet of a second low-temperature heat regenerator 5-7, and a cold-side outlet of the second low-temperature heat regenerator 5-7 is connected with a second inlet 5.11 of a third confluence valve; the outlet 5.12 of the third confluence valve is connected with the cold side inlet of the first medium temperature heat regenerator 5-8, and the cold side outlet of the first medium temperature heat regenerator 5-8 is connected with the inlet 5.1 of the second confluence valve;

the comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5 has the following working process: by CO₂Splitting at the second splitting valve 5-15: a portion of CO from the cold side of the first medium temperature regenerator 5-8₂Enters the cold side of a second high-temperature regenerator 5-9 to absorb heat and then enters a second FLiNaK-CO₂The heat exchanger 5-2 is heated and enters a second turbine 5-4 to do work, and CO after doing work₂Into the third FLiNaK-CO₂CO heated in the heat exchanger 5-3 and then enters the third turbine 5-5 to do work and do work again₂Enters the hot side of a second high-temperature heat regenerator 5-9 to release heat; another part of CO from the cold side of the first medium temperature regenerator 5-8₂Into the first FLiNaK-CO₂After absorbing heat in the heat exchanger 5-1, the heat enters a fourth turbine 5-6 to do work; CO from the hot side of the fourth turbine 5-5 and the second high temperature regenerator 5-9₂After confluence of the second confluence valve 5-16, the heat enters a first medium temperature heat regenerator 5-8 for heat release, then enters a first medium temperature heat regenerator 5-7 for heat release, and then is split by a third split valve 5-17: a part of CO2 is compressed and boosted by a second auxiliary compressor 5-10; another part of CO₂After being cooled by a second cold end heat exchanger 5-13, the refrigerant enters a second main compressor 5-11 for compression and pressure boosting, then enters a third cold end heat exchanger 5-14, and enters a third main compressor 5-12 for compression and pressure boosting again after being cooled; two strands of CO₂The mixture flows through the third flow merging valve 5-18, enters the cold side of the first medium temperature heat regenerator 5-8 to absorb heat, and then enters the second flow dividing valve 5-15 to form circulation.

As a preferred embodiment of the present invention, the core active zone 1-2 of the reactor body system 1 has a thermal power of 125MW, a core inlet temperature of 650 deg.C and a core outlet temperature of 700 deg.C, and FLiBe salt is used as a coolant, LiF and BeF₂The mole numbers are 67% and 33% respectively; the passive residual heat removal system 2 and the secondary loop system 4 adopt FLiNaK salt as a cooling working medium, and the mole fractions of LiF, NaF and KF are 46.5%, 11.5% and 42% respectively.

As a preferred embodiment of the invention, the core active area 1-2 of the reactor body system 1 adopts spiral cross-shaped fuel elements, and the TRISO nuclear fuel is dispersed in the matrix at 50% filling rate; nuclear fuel²³⁵The U enrichment degrees are respectively 15% and 17.5%; the fuel rods in the single component are arranged in a triangular shape, and the components are arranged in a triangular shape.

As a preferred embodiment of the invention, the FLiBe-CO of the reactor body system 1₂A main heat exchanger 1-4, a first FLiNaK-CO of a comprehensive utilization type supercritical carbon dioxide Brayton cycle system 5₂Heat exchanger 5-1, second FLiNaK-CO₂Heat exchanger 5-2 and third FLiNaK-CO₂The heat exchangers 5-3 are all printed circuit board type heat exchangers; FLiBe-FLiNaK main heat exchanger 1-5 of reactor body system 1, first FLiBe-FLiNaK waste heat discharge heat exchanger 1-6 and second FLiBe-FLiNaK waste heat discharge heat exchanger of passive waste heat discharge system 21-7, all are shell-and-tube heat exchangers.

In a preferred embodiment of the present invention, the thermal efficiency of the compact supercritical carbon dioxide brayton cycle system 3 is more than 48%, and the thermal efficiency of the comprehensive utilization supercritical carbon dioxide brayton cycle system 5 is more than 54%.

As a preferred embodiment of the invention, the reactor vessel 1-1 of the reactor body system 1 is less than 3.5 meters in diameter and less than 3 meters in height.

In a preferred embodiment of the present invention, the energy conversion system including the compact supercritical carbon dioxide brayton cycle system 3, the two-circuit system 4, and the comprehensive utilization supercritical carbon dioxide brayton cycle system 5 is not put into use at the same time, and the systems are switched as needed.

While the invention has been described in further detail with reference to specific preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.