Power plant

Abstract

A power plant system (10) includes a molten salt reactor assembly (20), a thermocline unit (30), a phase change heat exchanger (70, 72, 74), and a process thermodynamic system (80, 82, 84). The thermocline unit (30) includes an adiabatic tank (32), an initial inlet (38), a plurality of zone outlets (40, 42, 44), and a plurality of gradient zones (50, 52, 54) corresponding to each zone outlet and stacked in the tank. Each gradient zone (50, 52, 54) has a molten salt fraction (60, 62, 64) stored in a tank and stratified at a partial temperature corresponding to the molten salt supply from the molten salt reactor. The fused salt part at the higher part temperature generates heat energy for the process thermodynamic system needing the higher temperature, and the fused salt part at the lower part temperature generates heat energy for the process thermodynamic system needing the lower temperature. The system continuously pumps a supply of molten salt at a controlled rate to deliver a supply of heat exchange fluid to operate in a corresponding specific process thermodynamic system.

Description

[0001] This application is a divisional application of patent application No. 201980080058.2 (PCT / US2019 / 052317) entitled “Power Plant” filed by the applicant on September 22, 2019. Technical Field

[0002] The present invention relates to a power plant system. More specifically, the present invention relates to a nuclear power plant, such as a nuclear power plant with a molten salt reactor. More specifically, the present invention relates to a system for storing thermal energy from an integral molten salt reactor and converting it into usable energy. The present invention also relates to a method for storing and converting thermal energy. Background Art

[0003] A nuclear power plant is a thermal power plant with a nuclear reactor as the main heat source. In well-known applications, the heat from the controlled nuclear reaction produces steam, which drives a generator to generate electricity. Other power plants that use thermal energy to generate electricity include alternative energy sources, such as solar and wind energy. For these power plants that generate thermal energy, the storage and conversion of thermal energy in terms of capacity, efficiency and utility are limited to conventional heat exchangers and thermoclines. For some nuclear power plants, such as those based on light water reactors (LWRs), the amount of thermal energy is large and the temperature is relatively low, which affects the efficiency of converting thermal energy into work. For nuclear power plants with certain other nuclear reactors, the amount of thermal energy is large and the temperature is very high. Molten salt reactors (MSRs), especially integral molten salt reactors (IMSRs), produce this nuclear thermal energy, which can be used for higher-level thermal processes, such as hydrolysis and ammonia production. Since the temperature is much higher than the boiling point of water that produces steam, power generation is one of the lower functions of this nuclear thermal energy.

[0004] Conventional storage and conversion components are phase change heat exchangers and thermoclines. Various patents and patent applications have been published in the field of heat exchangers and thermoclines for power stations.

[0005] US Patent No. 8,739,512 issued to Mills on June 3, 2014 discloses a solar power plant that requires thermal energy storage due to the periodicity of the sun. An intermediate thermal energy storage unit is part of the system, and both thermocline tanks and phase change storage units are disclosed as options for the intermediate thermal energy storage unit.

[0006] U.S. Patent Publication No. 2018 / 0245485, issued to Conlon on August 30, 2018, also discloses a method for generating electricity for a solar power plant. The inconsistency of solar power generation requires that solar energy be stored as efficiently as possible for use at night. The method discloses multiple thermocline tanks with different temperatures based on thermal differences with a regulation cycle for power generation tasks. U.S. Patent No. 9,624,913, issued to Friesth on April 18, 2017, discloses multiple thermocline tanks for any renewable energy source (wind, solar, geothermal, etc.), not just solar power plants.

[0007] U.S. Patent Publication No. 2012 / 0319410 issued to Ambrosek et al. on December 20, 2012 discloses two phase change heat storage modules. The interaction of the two modules is more specific in terms of the heat energy output between the main module and the secondary module. U.S. Patent No. 8,955,320 issued to Xiang et al. on February 17, 2015 also describes a known phase change heat storage unit. The scope of this patent involves various controls on the thermal charging rate.

[0008] Other references treat phase change heat exchangers and thermocline units as somewhat interchangeable. U.S. Patent No. 9,651,313, issued May 16, 2017 to Trainham et al., teaches another system for a thermocline tank or phase change storage unit. U.S. Patent Publication No. 2017 / 0363368, issued December 21, 2017 to Bergan et al., is another multi-tank system having thermocline tanks and phase change storage units that are considered equivalent substitutes. It is recognized that in order to actually replace the thermocline and phase change heat exchanger, all supporting components and multiple other controllers need to be changed. Thermal storage systems can be interchangeable alternatives for thermal energy storage and conversion, but the physical components of the actual system cannot be simply "plug and play" interchanged.

[0009] These prior art references and the prior art of thermal storage and conversion components do not address the specific capacity, efficiency and utility of thermal energy from molten salt reactors.

[0010] It is an object of the present invention to provide a power plant system that accommodates the thermal energy capacity from an integral molten salt reactor.

[0011] An object of the present invention is to provide a power plant system for efficiently storing thermal energy from an integral molten salt reactor.

[0012] An object of the present invention is to provide a power plant system which properly utilizes thermal energy from an integral molten salt reactor.

[0013] It is another object of the present invention to provide an embodiment of a power plant system having a thermocline unit with a gradient zone corresponding to a portion of stratified molten salt stored in the thermocline unit.

[0014] Another object of the present invention is to provide an embodiment of a power plant system having a phase change heat exchanger corresponding to each gradient zone and a respective molten salt portion.

[0015] It is another object of the present invention to provide embodiments of a power plant system for delivering a supply of heat exchange fluid to a process thermal system.

[0016] It is a further object of the present invention to provide an embodiment of a power plant system having a phase change heat exchanger and a corresponding process thermal system cooperating with each other to supply a heat exchange fluid supply to a particular process thermal system.

[0017] It is a further object of the present invention to provide an embodiment of a power plant system with a molten salt portion that flows continuously through the thermocline unit according to the energy demand of the specific process thermal system.

[0018] It is a further object of the present invention to provide embodiments of a power plant system for delivering a heat exchange fluid supply to a process thermal system defined by a molten salt section and an adjacent phase change heat exchanger.

[0019] It is a further object of the present invention to provide an embodiment of a power plant system that safely and efficiently compensates for thermal energy surplus from a process thermal system and for dynamic changes in thermal energy demand.

[0020] These and other objects and advantages of the present invention will become apparent from a reading of the accompanying description and the appended claims. Summary of the invention

[0021] Embodiments of the present invention include a power plant system, comprising a molten salt reactor assembly having a molten salt supply at a first temperature, a thermocline unit fluidly connected to the molten salt reactor assembly, a plurality of phase change heat exchangers fluidly connected to the thermocline unit, and a plurality of process thermal systems. The molten salt reactor assembly includes a molten salt outlet and a salt return pipeline. The thermocline unit includes: an insulated tank having a top and a bottom; an initial inlet, which is fluidly connected to the molten salt outlet of the molten salt reactor; a plurality of zone outlets, which are arranged from the top of the tank to the bottom; and a plurality of gradient zones within the tank. Each zone outlet defines a corresponding gradient zone. The gradient zone can be stacked from the bottom end of the tank to the top end. Each gradient zone can have a molten salt portion at a partial temperature. The gradient zone of the tank corresponds to a thermal boundary between the stratified molten salt portions of the molten salt supply within the thermocline. These molten salt portions are separated by density, thereby forming a plurality of thermal boundaries and storing different thermal energy in each molten salt portion at a corresponding partial temperature.

[0022] The present invention includes each phase change heat exchanger connected to the corresponding outlet, the corresponding gradient zone and the adjacent phase change heat exchanger fluid. Each phase change heat exchanger includes: a salt inlet, which is connected to the corresponding zone outlet fluid; a salt outlet, which is connected to the salt return pipeline fluid of the molten salt reactor assembly; and a heat exchange fluid supply, which is in a heat exchange relationship with the corresponding molten salt portion of the corresponding gradient zone. In some embodiments, the heat exchange fluid supply is also connected to the adjacent phase change heat exchanger fluid. Thermal energy can be transferred between phase change heat exchangers, so that the power plant system can isolate thermal energy at a specific partial temperature for use by the process thermal system, or control the distribution of thermal energy to more than one partial temperature for use by two different process thermal systems.

[0023] Each process thermal system is fluidly connected to at least one phase change heat exchanger. The process thermal system receives useful thermal energy at a partial temperature suitable for the process. For example, a power plant system can provide thermal energy at a higher partial temperature to a process thermal system for hydrolysis and provide thermal energy at a lower partial temperature to a process thermal system for power generation. The thermal energy is managed so that a certain amount and high temperature molten salt supply at a first temperature from an integral molten salt reactor (IMSR) is not the only heat exchange relationship with the process thermal system. The molten salt supply of the IMSR can be efficiently stored and converted into useful thermal energy for more than one process thermal system.

[0024] Embodiments of the present invention include a method for storing and converting thermal energy. The method includes generating a molten salt supply at a first temperature from a molten salt reactor assembly and flowing or pumping the molten salt supply to a thermocline unit. The molten salt supply is layered within the thermocline unit to form a plurality of molten salt portions in the layer. Each molten salt portion has a partial temperature and corresponds to a gradient zone of the thermocline unit. Each partial temperature of the corresponding gradient zone is higher than the corresponding partial temperature of the corresponding gradient zone stacked below the corresponding gradient zone. The method also includes flowing or transferring the molten salt portion in the corresponding gradient zone to a plurality of phase change heat exchangers through the corresponding zone outlet. Each phase change heat exchanger is connected to an adjacent phase change heat exchanger and a molten salt reactor fluid through a corresponding gradient zone. At least one operating heat energy supply is generated from a plurality of phase change heat exchangers and molten salt portions. At least one operating heat energy supply is delivered to at least one process thermal system connected to a corresponding phase change heat exchanger fluid. The process thermal system receives available heat energy for a specific function of the process thermal system, even if the molten salt supply from the IMSR has a first temperature much higher than the partial temperature corresponding to at least one operating heat energy supply.

[0025] In some embodiments, the method includes generating more than one operating thermal energy supply. A first phase change heat exchanger and a second phase change heat exchanger generate a first operating thermal energy supply and a second thermal energy supply, respectively. These two different thermal energy supplies can represent an ammonia production supply as a first process thermal system and a power generation supply as a second process thermal system. The two process thermal systems can effectively receive available thermal energy for two functions at the same time, even if the molten salt supply from the IMSR has a first temperature that is much higher than the partial temperature corresponding to the first operating thermal energy supply or the second operating thermal energy supply. Additional phase change heat exchangers can generate additional operating thermal energy supplies for additional process thermal systems. The method can combine multiple operating thermal energy supplies from a single molten salt supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a front schematic diagram of an embodiment of a power plant system according to the present invention.

[0027] Figure 2 yes Figure 1 Rear schematic diagram of the embodiment showing the other side of the thermocline unit.

[0028] Figure 3 is a partial front schematic diagram of a first alternative embodiment of a power plant system having a phase change heat exchanger stacked around a thermocline unit.

[0029] Figure 4 is a partial front schematic diagram of a second alternative embodiment of a power plant system having a thermocline unit with an annular tank surrounding a stack of phase change heat exchangers.

[0030] Figure 5 is a flow chart of a power plant system and method for thermal energy according to the present invention. DETAILED DESCRIPTION

[0031] Thermal energy from an integral molten salt reactor (IMSR) requires consideration of the amount of thermal energy produced by the IMSR and the extremely high temperature molten salt supply. Conventional thermoclines have storage capacity for a certain amount of thermal energy, but the thermal energy becomes less useful, especially for high temperature process thermal systems or high temperature difference process thermal systems. When so much thermal energy is stored, the temperature at which the thermal energy is stored reduces the functionality of the high heat from the IMSR. Conventional phase change heat exchangers have the efficiency of converting thermal energy at higher temperatures, but the phase change is so dynamic that the storage capacity is very low. The present invention includes a nuclear power plant system 10 and method for thermal energy to address the specific considerations of molten salt reactors and particularly IMSRs.

[0032] refer to Figure 1 , 2and 5, an embodiment of a power plant system 10 includes a molten salt reactor assembly 20 having a molten salt supply 22 at a first temperature, a thermocline unit 30 fluidly connected to the molten salt reactor, a plurality of phase change heat exchangers 70, 72, 74 fluidly connected to the thermocline 30, and a plurality of process thermal systems 80, 82, 84 fluidly connected to at least one phase change heat exchanger 70, 72, 74.

[0033] The molten salt reactor assembly 20 includes a molten salt outlet 24 and a salt return line 26. The molten salt reactor assembly 20 includes a molten salt reactor with nuclear molten salt or fuel salt. Nuclear molten salt or fuel salt is a salt with nuclear fuel, such as uranium tetrafluoride, and due to health and safety considerations, the nuclear molten salt or fuel salt never actually leaves the molten salt reactor assembly 20. There may be a manifold and a second heat exchanger in the molten salt reactor assembly 20 to handle these nuclear aspects of the molten salt reactor or IMSR. These components are known in the prior art as background information, and these components can use coolant salt to manage nuclear fuel and heat from fuel salt. The different heat exchange loops of coolant salt in the molten salt reactor assembly 20 can be considered as part of the molten salt reactor assembly 20. For the present invention, the molten salt reactor assembly 20 has a molten salt supply 22 or working salt at a first temperature at the molten salt outlet 24. The molten salt supply 22 or working salt is not radioactive and is not a direct nuclear molten salt or fuel salt from the reactor. In practice, the molten salt supply 22 or working salt at the molten salt outlet 24 is at about 600° C., and the molten salt supply 22 or working salt is most often in heat exchange relationship with the coolant salt of the molten salt reactor assembly 20. The molten salt supply 22 or working salt does not contact the nuclear fuel of the fuel salt. As known in the prior art, the molten salt reactor assembly 20 may include a reactor and other components for removing radioactivity. For the present invention, the molten salt reactor assembly 20 includes a molten salt inlet 22 and a molten salt outlet 24. The molten salt supply 22 connected to the thermocline unit 30 fluid is not radioactive and can be the result of one or two other heat exchange relationships and manifold interactions that convert nuclear thermal energy into another thermal energy to be stored or processed or both.

[0034] The molten salt in the salt return line 26 is at a temperature lower than the first temperature. The molten salt in the return line 26 can be reused to cool further nuclear reactions and reheated back to the molten salt supply 22 at the first temperature through the molten salt outlet 24. The molten salt reactor assembly 20 may include an integral molten salt reactor (IMSR). A more compact and replaceable IMSR is an embodiment of the power plant system 10 of the present invention. The molten salt reactor assembly 20 may be a core unit and other components and a molten salt reactor assembly 20 for use as described above. Figure 1 and 2The IMSR of the connection of the nuclear reaction shown. In some embodiments, the molten salt supply 22 or working salt includes carrier salts, such as nitrates and chlorides. In contrast, the nuclear fuel in the nuclear molten salt or fuel salt can be uranium tetrafluoride, which cannot safely leave the molten salt reactor assembly 20. The tritium in the nuclear molten salt or fuel salt from the nuclear reaction must be removed, and other components in the molten salt reactor assembly 20 can perform this removal, such as a heat exchange loop with a coolant salt. The carrier salt or working salt can leave the molten salt reactor assembly 20 and can be selected from fluoride salts. Other types of salts can be selected, such as three different chloride salts, beryllium, potassium, and even zirconium can also be considered. In the present invention, the molten salt supply 22 is a mixture with different densities. There are at least two different molten salts in the molten salt supply 22 or working salt, so there are at least two densities. The molten salt supply 22 must be able to be divided into different layers according to density.

[0035] An embodiment of the thermocline unit 30 includes an insulated tank 32 having a top end 34 and a bottom end 36, an initial inlet 38 connected to a molten salt outlet fluid of a molten salt reactor, a plurality of zone outlets 40, 42, 44 arranged from the top end 34 to the bottom end 36 of the insulated tank 32, and a plurality of gradient zones 50, 52, 54 within the insulated tank 32. The insulated tank 32 may also include conventional components inside, such as graphite or sand heat sinks, as a dense mass to absorb additional heat. Conventional thermocline components are known in the art.

[0036] The insulated tank 32 may be generally cylindrical with an initial inlet 38 at or near the top end 34. The molten salt supply 22 enters the insulated tank 32 through the initial inlet 38 and must settle in the insulated tank 32. The zone outlets 40, 42, 44 are dispersed between the top end 34 and the bottom end 36. The zone outlets 40, 42, 44 may be arranged linearly or offset from each other, but the zone outlets 40, 42, 44 must be located at different distances from the top end 34 of the insulated tank 32. Each zone outlet 40, 42, 44 defines a corresponding gradient zone 50, 52, 54. These gradient zones 50, 52, 54 are stacked between the top end 34 and the bottom end 36 according to the different distances from the top end 34 of the insulated tank 32 of the zone outlets 40, 42, 44.

[0037] Each gradient zone 50, 52, 54 has a molten salt portion 60, 62, 64 at a partial temperature. As the molten salt supply 22 is deposited in the insulating tank 32, the molten salt portions 60, 62, 64 form stratified layers. The molten salt supply 22 is composed of different salts with different densities; therefore, the insulating tank 32 allows the molten salt supply 22 to be divided into these different portions. There are thermal boundaries between adjacent molten salt portions 60, 62, 64, which serve as conventional thermal boundaries of conventional thermoclines. In the present invention, the thermocline unit 30 has components that result in multiple thermal boundaries and different molten salt portions 60, 62, 64 separated and insulated by multiple thermal boundaries.

[0038] Each portion of the corresponding gradient region 50, 52, 54 has a higher temperature than the corresponding portion of the corresponding gradient region 50, 52, 54 stacked below the corresponding gradient region 50, 52, 54. Figure 5 , as an example, the partial temperature of the molten salt portion 62 in the gradient zone 52 is lower than the molten salt portion 60 in the gradient zone 50, and higher than the molten salt portion 64 in the gradient zone 54. The gradient zones 50, 52, 54 can be adjusted by placing the corresponding zone outlets 40, 42, 44 to match the stratification of the molten salt supply 22 into the molten salt portions 60, 62, 64 as layers.

[0039] In one embodiment, the initial inlet 38 of the thermocline unit 30 is connected to the top end 34 of the insulated tank 32 so as to define a top zone outlet 40 adjacent to the top end 34 of the insulated tank 32 and a corresponding top gradient zone 50 having a top molten salt portion 60 at the top portion temperature, such as Figure 2 and 5 shown. Figure 1-2 Also shown are additional inlets 38A near the bottom end 36 of the insulated tank 32 and between the bottom end 36 and the top end 34 of the insulated tank 32. There may be multiple inlets 38, 38A, 38A so that more than one fluid is connected to the thermocline unit 30. The molten salt supply 22 must have time to settle, so injection at multiple levels in the insulated tank 32 is an embodiment of the present invention. The initial inlet 38 at the top end 34 is just one embodiment of the present invention. The first temperature of the molten salt supply 22 remains higher than the top portion temperature of the top molten salt portion 60, but the portion temperature of the molten salt portions 62, 64 below the top molten salt portion 60 decreases toward the bottom end 36 of the insulated tank 32.

[0040] In some embodiments, each phase change heat exchanger 70 , 72 , 74 is fluidly connected to a corresponding zone outlet 40 , 42 , 44 and a corresponding gradient zone 50 , 52 , 54 . Figure 1 , 25 show that each phase change heat exchanger 70 , 72 , 74 is fluidly connected to adjacent phase change heat exchangers 72 , 74 , 70 and the molten salt reactor assembly 20 , particularly through the corresponding zone outlets 40 , 42 , 44 of the thermocline unit 30 and the initial inlet 38 of the thermocline unit 30 .

[0041] Figure 1 , 2 and 5 also show that each phase change heat exchanger 70, 72, 74 includes a salt inlet 70A, 72A, 74A fluidly connected to the corresponding zone outlet 40, 42, 44, a salt outlet 70B, 72B, 74B fluidly connected to the salt return pipeline 26 of the molten salt reactor assembly 20, and a heat exchange fluid supply 70C, 72C, 74C in heat exchange relationship with the corresponding molten salt portion 60, 62, 64 of the corresponding gradient zone 50, 52, 54.

[0042] Embodiments of the present invention include heat exchange fluid supplies 70C, 72C, 74C connected to adjacent phase change heat exchangers 72, 74, 70 fluids. Heat energy can be transferred between phase change heat exchangers 70, 72, 74 to achieve a synergistic effect. For example, if heat energy is required at a partial temperature corresponding to the molten salt portion 62, the heat energy of the molten salt portion 60 can be transferred to the phase change heat exchanger 72 through the phase change heat exchanger 70. The higher temperature of the molten salt portion 60 is still useful for requirements at different temperatures.

[0043] Figure 1 and 2 Each heat exchange fluid supply including a working molten salt supply 70D, 72D, 74D is shown. The heat exchange relationship in each phase change heat exchanger 70, 72, 74 can be between the corresponding molten salt portion 60, 62, 64 and a separate heat exchange fluid, such as the working molten salt supply 70D, 72D, 74D. The working molten salt supply 70D, 72D, 74D transfers thermal energy to the process thermal system 80, 82, 84 in a separate loop from the molten salt supply 22, the molten salt portion 60, 62, 64 and the return line 26 to the molten salt reactor assembly 20, as shown in FIG. Figure 5 There may be other conventional components in the phase change heat exchangers 70, 72, 74, such as other heat exchange fluids that transfer heat between the molten salt portions 60, 62, 64 and the final working molten salt supply 70D, 72D, 74D.

[0044] The working molten salt supplies 70D, 72D, 74D are never identical to the molten salt supply 22 , the molten salt portions 60 , 62 , 64 , and the return line 26 . Figure 1An embodiment is shown with a single loop from the molten salt supply 22, the molten salt portions 60, 62, 64, the phase change heat exchangers 70, 72, 74 and the return line 26. After using the thermal energy from the molten salt supply 22 at the first temperature, there is a loop to return the molten salt to the molten salt reactor assembly 20. The molten salt supply 22 or working salt is closer to the radioactivity in the molten salt reactor assembly 20 and therefore is never pumped and transported through the power station as part of the inherent safety of the entire IMSR system.

[0045] The working molten salt supplies 70D, 72D, 74D are sealed with the molten salt supply 22 and are not fluidly connected to the molten salt supply 22. The working molten salt supplies 70D, 72D, 74D are in heat exchange relationship with the corresponding molten salt portions 60, 62, 64 of the molten salt supply 22. The working molten salt supplies 70D, 72D, 74D may also include carrier salts, such as nitrates, chlorides, and fluorides. These working molten salt supplies 70D, 72D, 74D do not have a core component, but other salts may also be selected. There is no mixture or multi-density requirement for the working molten salt supplies 70D, 72D, 74D.

[0046] Figure 3 and 4 Various embodiments of a plurality of phase change heat exchangers 70 , 72 , 74 , 170 , 172 , 174 , 270 , 272 , 274 are shown. Figure 1 and 2 Phase change heat exchangers 70, 72, 74 are shown arranged in an array. Phase change heat exchangers 70, 72, 74 can be stand-alone units with standard plumbing, pump and valve connections. Phase change heat exchangers 70, 72, 74 do not have any physical contact with thermocline unit 30. Figure 3 Another embodiment of the phase change heat exchangers 170, 172, 174 stacked around the insulated tank 32 is shown. The zone outlets of the thermocline units, the salt inlets of the phase change heat exchangers 170, 172, 174, the salt outlets of the phase change heat exchangers 170, 172, 174, and the heat exchange fluid supply of the phase change heat exchangers 170, 172, 174 are not shown in detail. Standard piping, pumps and valve connections include these components known to those of ordinary skill in the art. In a stacked configuration, these components can be closer together to achieve a more efficient heat exchange relationship and less pipe waste heat.

[0047] Figure 4Another alternative embodiment is shown, the tank of the thermocline unit 30 includes an annular tank 232 that defines a central area 233. In this embodiment, a plurality of phase change heat exchangers 270, 272, 274 are stacked in the central area 233 of the annular tank 232. The zone outlet of the thermocline unit, the salt inlet of the phase change heat exchanger 170, 172, 174, the salt outlet of the phase change heat exchanger 270, 272, 274, and the heat exchange fluid supply of the phase change heat exchanger 270, 272, 274 are not shown in detail as well. Standard pipelines, pumps and valve connections include these components known to those of ordinary skill in the art. In the stacked configuration of the annular tank 232, these components can also be more closely together to achieve a more effective heat exchange relationship and even less pipeline waste heat. Especially in the case of having a thermocline unit 232 around the phase change heat exchanger 270, 272, 274, the reduction of waste heat is greater.

[0048] Figure 1 , 3 4 shows a schematic diagram of the process thermal systems 80, 82, 84 of the present invention. The multiple process thermal systems 80, 82, 84 can be a desalination system 84, a hydrogen production system 82 such as a high temperature steam electrolysis (HTSE) system, or a power generation system 80. The process thermal system 80, 82, 84 refers to any equipment that uses thermal energy. The power plant system 10 controls the thermal energy from the IMSR to be efficiently stored, converted and distributed to any process thermal system 80, 82, 84. The process thermal systems 80, 82, 84 have different thermal energy requirements in terms of temperature and amount. The power plant system 10 allows effective thermal energy to be provided at a desired temperature, even if it is lower or higher for the superheat of some process thermal systems.

[0049] Figure 1-5 Additional embodiments are shown in which the second thermal energy system 90, 92 has a thermal energy supply 94, 96 at a second temperature and is in heat exchange relationship with the thermocline unit 30. The power plant system 10 is not limited to the molten salt reactor assembly 20 as the only thermal energy source. The additional thermal energy system 90, 92 is schematically shown. The second thermal energy system 90, 92 can be in heat exchange relationship with at least one heat exchange fluid supply 70C, 72C, 74C. In particular, there is a heat exchange relationship with the corresponding phase change heat exchanger 70, 72, 74, and the corresponding gradient zone of the thermocline unit 30 has a corresponding molten salt portion at a corresponding portion temperature. When the corresponding portion temperature is lower than the second temperature, the second thermal energy system 90, 92 transfers thermal energy to the heat exchange fluid supply 70C, 72C, 74C for use by the process thermal system 80, 82, 84. The second thermal energy system 90, 92 is independent of the molten salt supply 22 from the molten salt reactor assembly 20. The second thermal energy system 90, 92 is an alternative embodiment for recovering thermal energy from these alternative energy sources.Other connections for transferring thermal energy from the second thermal energy system 90, 92 are also possible.

[0050] Figure 1-5 A second thermal energy system is shown as a wind generator 90 and / or a solar generator 92. The power plant system 10 has special compatibility with these alternative energy sources. For example, for the solar generator 92, due to the inconsistent sunlight at night. The low level of thermal energy at night is not useful to the process thermal systems 80, 82, 84. However, as a contributor to the power plant system 10 of the present invention, the previously wasted thermal energy can now be used. Similarly, when the wind is not blowing, the wind generator 90 is still able to produce useful thermal energy, which was previously wasted without conversion to the process thermal systems 80, 82, 84.

[0051] The present invention includes a method of using the power plant system 10 for thermal energy, particularly storing and converting thermal energy from an IMSR. Figure 5 An embodiment of the method is shown. A molten salt supply 22 at a first temperature is generated from a molten salt reactor assembly 20. The molten salt reactor assembly 20 may include an IMSR or other salt reactor. The molten salt supply 22 at the first temperature is very hot and leaves the molten salt reactor assembly 20 through a molten salt outlet 24. In some embodiments, the first temperature may be about 650°C. The spent molten salt is returned to the molten salt reactor assembly 20 through a salt return line 26 for recovery of the molten salt. After leaving the molten salt reactor assembly 20, the molten salt supply 22 flows to a thermocline unit 30 that is fluidly connected to the molten salt reactor assembly 20. The flowing step may be any other known method of pumping or transporting molten salt. There may be natural circulation forces or even pumps. The thermocline unit 30 of the method is Figure 1-2 The thermocline unit 30 has an insulated tank 32 with a top end 34 and a bottom end 36, an initial inlet 38 fluidly connected to the molten salt outlet 24 of the molten salt reactor assembly 20, a plurality of zone outlets 40, 42, 44 arranged from the top end 34 of the insulated tank 32 to the bottom end 36, and a plurality of gradient zones 50, 52, 54 within the insulated tank 32. Each zone outlet 40, 42, 44 defines a corresponding gradient zone 50, 52, 54, and the gradient zones 50, 52, 54 are stacked between the top end 34 and the bottom end 36. In the thermocline unit 30, the method includes stratifying the molten salt supply 22 within the insulated tank 32 of the thermocline unit 30 to form a plurality of molten salt portions 60, 62, 64. Each molten salt portion 60, 62, 64 has a partial temperature and a corresponding gradient zone 50, 52, 54.

[0052] The stratification step produces multiple thermal boundaries between the molten salt parts 60,62,64. These thermal boundaries isolate the layers of the molten salt parts 60,62,64 from each other, just like conventional or even naturally occurring thermocline lakes storing thermal energy at different water layers. In the present invention, the method includes stratifying molten salt supply 22, including stratifying by density due to different salts in the mixture. Once separated by density, the molten salt supply 22 is also separated by temperature, causing each molten salt part 60,62,64 to be in the corresponding part temperature. In one embodiment, each part temperature of the molten salt part in the corresponding gradient zone is higher than the corresponding part temperature of the corresponding molten salt part in the gradient zone stacked below the corresponding gradient zone.

[0053] The method further includes flowing the molten salt portions 60, 62, 64 in the respective gradient zones 50, 52, 54 through the respective zone outlets 40, 42, 44 to a plurality of phase change heat exchangers 70, 72, 74. These phase change heat exchangers 70, 72, 74 are Figure 1-2 Phase change heat exchangers 70, 72, 74 are each fluidly connected (via thermocline unit 30) to adjacent phase change heat exchangers 72, 74, 70 and molten salt reactor assembly 20. Molten salt supply 22 is recycled from phase change heat exchangers 70, 72, 74 back to molten salt reactor assembly 20 via salt return line 26. Molten salt supply 22 can be reheated by known components, such as manifolds and other heat exchangers that interact with nuclear reactors and nuclear molten salts. In the present invention, no radioactive or nuclear salt is used to leave molten salt reactor assembly 20.

[0054] Embodiments of the method also include generating at least one operating heat supply 98, 99 from a plurality of phase change heat exchangers 70, 72, 74 and molten salt portions 60, 62, 64. The operating heat supply 98, 99 is an available heat supply for process thermal systems 80, 82, 84. For selected process thermal systems 80, 82, 84, the operating heat 98, 99 is more efficient than the original heat from the molten salt supply 22 directly from the molten salt reactor assembly 20. The term "operation" means that the heat 98, 99 is more efficient and compatible than the original heat. The temperature of the operating heat 98, 99 can be lower than the first temperature of the molten salt supply 22 of the process thermal system 80 (such as a generator). But for other process thermal systems that require superheating or "capping" thermal systems, the operating heat 98, 99 can also be at a higher temperature than the first temperature of the molten salt supply 22. Some high temperature steam electrolysis (HTSE) can use a superheated heat exchange fluid supply.

[0055] Embodiments of the method also include delivering at least one operating heat energy supply 98, 99 to at least one process thermal system 80, 82, 84 connected to the corresponding phase change heat exchanger 70, 72, 74 fluid. The delivery step is similar to the flow step. The delivery step includes any prior art method of transferring thermal energy from the heat exchange fluid supply 70C, 72C, 74C. For example, the activity can pump the heat exchange fluid supply 70C, 72C, 74C to the generator 80, which is a steam generator to rotate the turbine to generate electricity. The heat exchange fluid supply 70C, 72C, 74C of each phase change heat exchanger 70, 72, 74 is sealed relative to the molten salt supply 22. The molten salt supply 22 does not have a fluid connection for direct pumping to the process thermal system 80, 82, 84. The molten salt supply 22 interacts closer to the core component and does not exceed the circulation loop of the phase change heat exchanger 70, 72, 74. The heat exchange fluid supplies 70C, 72C, 74C can further interact with other heat exchangers controlled by the power plant system 10. For example, the heat exchange fluid supply 72C can deliver an operating heat supply to a hydrogen production system as a process thermal system 82. The heat exchange fluid supply 72C can still have useful thermal energy for lower levels of temperature. Therefore, the heat exchange fluid supply 72C can also deliver an operating heat supply to a steam generator as a generator of the process thermal system 80. The heat exchange fluid supply 72C is recycled back to the corresponding phase change heat exchanger 72 to be recharged for more work of delivering another operating heat supply.

[0056] An alternative embodiment of the present invention includes a generating step including generating a first operating thermal energy supply 98 from one of the plurality of phase change heat exchangers 70 and a corresponding molten salt portion 60, and generating a second operating thermal energy supply 99 from another of the plurality of phase change heat exchangers 72 and another corresponding molten salt portion 62. The molten salt supply 22 may have such a high thermal energy than more than one operating thermal energy supply 98, 99 that may be formed by the power plant system 10. In this embodiment, the delivering step includes delivering the first operating thermal energy supply 98 to a first process thermal system 82 fluidly connected to one of the plurality of phase change heat exchangers 72, and delivering the second operating thermal energy supply 99 to a second process thermal system 84 fluidly connected to another of the plurality of phase change heat exchangers 74. The large capacity and high temperature of the molten salt supply 22 may power more than one process thermal system 80, 82, 84, even if these process thermal systems 80, 82, 84 require different molten salt portions 60, 62 at different temperatures to obtain higher efficiency relative to the original thermal energy of the molten salt supply 22.

[0057] In another alternative embodiment, the phase change heat exchangers 70, 72, 74 are cooperative. When the demand for heat energy of a process thermal system, such as hydrogen production as the process thermal system 72, increases, the other process thermal systems 70, 74 can reduce or even stop extracting their corresponding operating heat energy, so that more heat energy can be dedicated to hydrogen production as the process thermal system 72. In this embodiment of the method, the delivery step includes delivering the first operating heat energy supply 98 to another of the multiple phase change heat exchangers 72. Then, the generation step includes generating a second operating heat energy supply 99 from another of the multiple phase change heat exchangers 74 and another corresponding molten salt portion 64 and from the first operating heat energy supply 98. In this example, the thermal energy of the process thermal system 82 can be redirected to hydrogen production associated with the second operating heat energy at the phase change heat exchanger 74.

[0058] In yet another alternative embodiment, the method of the present invention solves the problem of the capacity of the molten salt supply 22 from the IMSR as a molten salt reactor assembly 20. In this method, the steps of making the molten salt portions 60, 62, 64 in the corresponding gradient zones 50, 52, 54 flow to multiple phase change heat exchangers 70, 72, 74 through the corresponding zone outlets 40, 42, 44 and the steps of generating at least one operating heat supply 98, 99 from multiple phase change heat exchangers and molten salt portions are continuous. The power plant system 10 can continue to operate and keep the molten salt supply 22 flowing. There is no increase, and there is no time to wait for the heat exchange fluid to charge or cool. The thermal stress is small, especially compared with the phase change heat exchangers of the prior art with sudden dynamic phase changes at higher temperatures. The method of the present invention having a power plant system 10 has a greater capacity for storing thermal energy, and the molten salt portion acts and cooperates between the partial temperatures. In this embodiment, the method also includes adjusting the flow step and the rate of the generation step of the corresponding phase change heat exchanger. Although the rate may slow down, the rate will not stop. One rate may increase while the other decreases due to the demands of the process thermal system.

[0059] In yet another alternative embodiment, the method of the present invention is compatible with other alternative energy sources. The method may include a step of supplying a heat energy supply 94, 96 at a second temperature that is in a heat exchange relationship with at least one of the phase change heat exchangers 70, 72, 74. The second thermal energy system 90, 92 can be in a heat exchange relationship with the corresponding gradient zone 50, 52, 54 of the thermocline unit 30 and the corresponding heat exchange fluid supply 70C, 72C, 74C of the corresponding salt portion at the corresponding portion temperature. According to the process thermal system 80, 82, 84 associated with the phase change heat exchanger 70, 72, 74, the heat energy supply 94, 96 is in a heat exchange relationship with the corresponding heat exchange fluid supply 70C, 72C, 74C. For example, the solar panel as the second thermal energy system 92 has a heat energy supply 96 compatible with the heat exchange relationship of the phase change heat exchanger 70. The phase change heat exchanger 70 has a heat exchange fluid 70C, which generates operating heat energy for power generation as the process thermal system 80. The temperature is relatively low, and the thermal energy supply 96 cannot provide any high temperature heat for hydrogen production, which is related to the phase change heat exchanger 72 used as the HTSE of the process thermal system 82. The thermal energy supply 96 is still useful and is incorporated into the power plant system 10 for the process thermal system 80, or used as capping heat for another process thermal system 82, 84. The phase change heat exchanger 70 corresponding to the second thermal energy system 92 remains in fluid connection with the corresponding molten salt portion 60 of the molten salt supply 22 in the corresponding gradient zone 50 of the thermocline unit 30.

[0060] This alternative embodiment addresses the alternative energy sources of wind turbines 90 and solar generators 92. The method of using the power plant system 10 addresses the special compatibility of thermal energy that is inconsistent with typical alternative energy sources. Known nighttime or windless thermal energy drops reduce the reliability of alternative energy sources. Even though cleaner for the environment, the lack of reliability has hindered the widespread adoption of these technologies by wind and solar energy. The low levels of thermal energy during these drops are not useful for the process thermal systems 80, 82, 84. In the method of the present invention, these low levels can become useful as contributors to the power plant system 10 of the present invention. The thermal energy that was previously wasted can now be used for the process thermal systems 80, 82, 84 at all times.

[0061] The power plant system of the present invention accommodates the thermal energy capacity from molten salt reactor assemblies, particularly assemblies having integral molten salt reactors (IMSRs). These reactors generate such large amounts of thermal energy at such high temperatures that conventional thermal storage and heat conversion devices cannot effectively and efficiently utilize the thermal energy generated. The power plant system of the present invention includes a thermocline unit having multiple zone outlets and multiple gradient zones to effectively store the molten salt supply in the molten salt portion. Therefore, the present invention has the storage capacity of the thermocline without reducing the utilization of thermal energy. The thermal energy stored in the thermocline is no longer limited to the almost useless temperature differences in conventional thermoclines. When thermal energy is stored in the power plant system of the present invention, the higher temperatures generated by the IMSR are no longer wasted.

[0062] The present invention also includes a phase change heat exchanger corresponding to each gradient zone and the corresponding molten salt portion. Depending on the needs of the downstream process thermal system, the operating heat supply can now be provided at different heat energy levels. The high heat supplied from the molten salt of the molten salt reactor assembly with IMSR can now be used for high heat functions, such as hydrogen production, while also being stored, and also used for low heat functions, such as power generation. Less heat energy is wasted.

[0063] The power plant system of the present invention delivers a heat exchange fluid supply to a process thermal system for operating heat supply. The operating heat supply is more efficient and compatible with the process thermal system relative to raw heat directly from the molten salt supply with the IMSR assembly. It does not take a sledgehammer to drive a thumbtack into a cork board, even a sledgehammer will do the job. Likewise, a molten salt supply with conventional heat storage and conversion is a sledgehammer. The present invention is a system and method for using a molten salt supply for different process thermal systems, even those process thermal systems that do not require a high heat and high volume molten salt supply.

[0064] In addition, the power plant system includes a phase change heat exchanger and a corresponding process thermal system that cooperate with each other. This feature allows the molten salt supply to be used for a single process thermal system or multiple process thermal systems, even if these process thermal systems have different thermal energy requirements. When there is a high demand for a process thermal system, such as a high demand for power generation, the phase change heat exchanger cooperates to direct the heat energy from the single phase change heat exchanger corresponding to a process thermal system, and the molten salt supply comes directly from the component with IMSR. The power plant system can still only generate an operating thermal energy supply for the process thermal system, rather than more than one operating thermal energy supply. One operating thermal energy supply is still more efficient than the original thermal energy of the molten salt supplied directly from the component with IMSR.

[0065] The cooperation of the phase change heat exchanger also enables the power plant system to operate continuously. The molten salt portion flows continuously through the thermocline unit into the gradient zone, so that the power plant system responds to the immediate energy demand of the specific process thermal system. The phase change heat exchanger can be adjusted to direct more thermal energy to the desired phase change heat exchanger that is already working, rather than increasing the conventional heat exchanger temperature rise to collect more thermal energy in the molten salt supply. The thermal stress on the components of the power plant system is reduced. The conventional heat exchanger is not repeatedly impacted by the molten salt supply at the first temperature, and there is no cooling period of the heat exchange fluid in the conventional heat exchanger. The molten salt supply flows continuously through the thermocline unit and, in some cases, through the phase change heat exchanger itself.

[0066] There are dynamic changes in heat supply and heat demand. Heat supply may surge, such as the sun at dawn on the solar panels. This influx of heat supply from the second heat system can now be combined into a stable and continuous system with a flowing molten salt supply. The sudden influx of heat supply does not require a "heating" period or any violent reaction in the phase change heat exchanger to suddenly change the phase. Heat supply can now be combined without thermal stress on the components of the system. Similarly, heat demand can be met. A steel manufacturing plant will suddenly draw a lot of electricity when it goes online in the morning. The present power station system can redirect the heat exchange relationship to the operating heat supply of the generator as a process thermal system to solve this new consumption of the operating heat supply required by the generator as a process thermal system, rather than requiring a large and significant increase in the phase change heat exchanger. The molten salt supply does not have to be suddenly pumped faster or more dangerous. The molten salt part with a temperature higher than the temperature required by the generator has been stratified in the thermocline unit for the available heat energy that can be directed to the phase change heat exchanger corresponding to the generator. The heat exchange fluid supply does not have to be more violent or pressured to the physical components of the phase change heat exchanger. Heat exchange fluid supply

[0067] Depending on the heat exchange fluid supply, the molten salt from the assembly with the IMSR can be circulated through the thermocline unit to the phase change heat exchanger and then circulated back through the return line after the heat energy is released. The heat energy can be transferred to a separate heat exchange fluid supply in the phase change heat exchanger to perform the work of the process thermal system. No nuclear molten salt leaves the molten salt reactor assembly, but the heat energy is safely and efficiently transferred to the heat exchange fluid supply corresponding to the process thermal system. Different operating heat energy supplies are maintained from one molten salt supply. There may be additional heat exchangers before reaching the process thermal system.

[0068] The foregoing disclosure and description of the present invention are illustrative and explanatory. Various changes may be made to the details of the structures, constructions, and methods shown without departing from the true spirit of the present invention.

Claims

1. A power station system 10, comprising: a molten salt reactor assembly 20 having a molten salt supply 22 at a first temperature and including a molten salt outlet 24 and a salt return line 26; a thermocline unit 30, which is fluidly connected to the molten salt reactor assembly, Wherein, the thermocline unit comprises: an insulated tank 32 having a top end 34 and a bottom end 36; an initial inlet 38 fluidly connected to the molten salt outlet of the molten salt reactor assembly; and a plurality of gradient zones 50, 52, 54 within the insulated tank, the gradient zones being stacked between the top end and the bottom end; Wherein, each gradient zone has a molten salt portion 60, 62, 64 at a partial temperature; A plurality of phase change heat exchangers 70, 72, 74, each phase change heat exchanger is fluidly connected to a corresponding gradient zone, wherein each phase change heat exchanger is fluidly connected to an adjacent phase change heat exchanger and the molten salt reactor assembly, Wherein, each phase change heat exchanger comprises: Salt inlets 70A, 72A, 74A, which are fluidly connected to the corresponding gradient zones; a salt outlet 70B, 72B, 74B fluidly connected to the salt return line of the molten salt reactor assembly; and a heat exchange fluid supply 70C, 72C, 74C in heat exchange relationship with a corresponding molten salt portion of said corresponding gradient zone, said heat exchange fluid supply being in fluid connection with said adjacent phase change heat exchanger; and A plurality of process thermal systems 80, 82, 84, each process thermal system being fluidly connected to at least one phase change heat exchanger.

2. The power plant system according to claim 1, wherein: The molten salt reactor assembly includes an integral molten salt reactor.

3. The power plant system according to claim 1, wherein: The molten salt supply 22 includes a plurality of carrier salts.

4. The power plant system according to claim 3, wherein: The carrier salt is selected from nitrates, chlorides, fluorides, beryllium salts, potassium salts and zirconium salts.

5. The power plant system according to claim 1, wherein: Each portion of a corresponding gradient zone has a higher temperature than a corresponding portion of a corresponding gradient zone stacked below the corresponding gradient zone.

6. The power plant system according to claim 1, wherein: The initial inlet is connected to the top end of the thermally insulated tank to define a top gradient zone having a top molten salt portion at a top portion temperature, the first temperature being higher than the top portion temperature.

7. The power plant system according to claim 1, wherein: The heat exchange fluid supply includes a supply of working molten salt 70D, 72D, 74D.

8. The power plant system according to claim 1, wherein: The plurality of phase change heat exchangers are arranged in one of an array 70 , 72 , 74 and a stack surrounding the insulated tanks 170 , 172 , 174 .

9. The power plant system according to claim 1, wherein: The insulated tank of the thermocline unit includes an annular tank 232 defining a central region 233 , wherein the plurality of phase change heat exchangers 270 , 272 , 274 are stacked within the central region of the annular tank.

10. The power plant system according to claim 1, wherein: A process thermal system among the plurality of process thermal systems is selected from a desalination system 84 , a hydrogen production system 82 , and a power generation system 80 .

11. The power plant system according to claim 1, further comprising: A second thermal energy system 90, 92 having a thermal energy supply 94, 96 at a second temperature and in heat exchange relationship with at least one heat exchange fluid supply.

12. The power plant system according to claim 11, wherein: The second thermal energy system is in heat exchange relationship with a corresponding phase change heat exchanger, and the corresponding phase change heat exchanger of the second thermal energy system is connected to a corresponding gradient zone fluid of the thermocline unit having a corresponding molten salt portion at a corresponding portion temperature, and the corresponding portion temperature is lower than the second temperature.

13. The power plant system according to claim 11, wherein: The second thermal energy system is selected from a wind generator 90 and a solar generator 92 .

14. A method for thermal energy, the method comprising the steps of: producing a molten salt supply 22 at a first temperature from a molten salt reactor assembly 20 including a molten salt outlet 24 and a salt return line 26; causing the molten salt supply to flow to a thermocline unit 30 fluidly connected to the molten salt reactor assembly, Wherein, the thermocline unit comprises: an insulated tank 32 having a top end 34 and a bottom end 36; an initial inlet 38 fluidly connected to the molten salt outlet of the molten salt reactor assembly; and a plurality of gradient zones 50, 52, 54 within the insulated tank, the gradient zones being stacked from the bottom end to the top end; stratifying the molten salt supply 22 within the thermocline unit to form a plurality of molten salt portions 60, 62, 64, each molten salt portion having a partial temperature and a corresponding gradient zone, wherein each portion of the corresponding gradient zone has a temperature higher than a corresponding portion of the corresponding gradient zone stacked below the corresponding gradient zone; allowing the molten salt portion in the corresponding gradient zone to flow to a corresponding phase change heat exchanger among a plurality of phase change heat exchangers, wherein each phase change heat exchanger is fluidly connected to an adjacent phase change heat exchanger and the molten salt reactor assembly; generating at least one operating thermal energy supply 98, 99 from said plurality of phase change heat exchangers and said molten salt portion; and The at least one operating heat energy supply 98, 99 is delivered to at least one process thermal system 80, 82, 84 fluidly connected to a corresponding phase change heat exchanger of the plurality of phase change heat exchangers.

15. The method for thermal energy according to claim 14, wherein: The step of generating at least one supply of operating thermal energy comprises: generating a first operating thermal energy supply from one of the plurality of phase change heat exchangers and a corresponding molten salt portion; and A second supply of operating thermal energy is generated from another one of the plurality of phase change heat exchangers and another corresponding molten salt portion.

16. The method for thermal energy according to claim 15, wherein: The delivery steps include: delivering the first operating heat supply to a first process thermal system fluidly connected to the one of the plurality of phase change heat exchangers; and The second operating heat supply is delivered to a second process thermal system fluidly connected to the other one of the plurality of phase change heat exchangers.

17. The method for thermal energy according to claim 15, wherein: The delivery steps include: delivering the first operating heat supply to the other one of the plurality of phase change heat exchangers, and The step of generating a second operating heat supply comprises: A second operating heat supply is generated from another one of the plurality of phase change heat exchangers and another corresponding molten salt portion and from the first operating heat supply.

18. The method for thermal energy according to claim 14, wherein: The steps of flowing said molten salt portions in respective gradient zones to a plurality of phase change heat exchangers and generating at least one operating thermal energy supply 98, 99 from said plurality of phase change heat exchangers and said molten salt portions are continuous, and Wherein the at least one process thermal system regulates respective rates of the steps of flowing the molten salt portion and generating at least one operating thermal energy supply.

19. The method for thermal energy according to claim 14, further comprising the steps of: supplying thermal energy from a second thermal energy system at a second temperature, Wherein, the second heat energy supply is in a heat exchange relationship with at least one of the plurality of phase change heat exchangers corresponding to the second temperature, and the second heat energy supply is in a heat exchange relationship with a corresponding heat exchange fluid supply.

20. The method for thermal energy according to claim 19, wherein: The step of generating at least one supply of operating thermal energy comprises: Heat of the second thermal energy supply from the second thermal energy system is exchanged with the corresponding heat exchange fluid supply.

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