阅读说明：本技术 一种用于光热电站的储热介质输送系统 (Heat storage medium conveying system for photo-thermal power station ) 是由 余志勇 唐亚平 周慧 周楷 毕文剑 孙峰 唐娟 童郭凯 于 2020-07-27 设计创作，主要内容包括：本发明提供了一种用于光热电站的储热介质输送系统,包括：高位罐子系统,所述高位罐子系统包括用于存储储热介质的高位罐,其特征在于,还包括储热介质传输子系统；所述高位罐子系统与所述储热介质传输子系统连接；所述储热介质传输子系统包括低位罐；所述低位罐的安装高度低于所述高位罐；所述低位罐的体积小于所述高位罐的体积；所述储热介质可部分或全部依靠自身重力从所述高位罐进入所述低位罐,所述低位罐上设置有输送泵,所述储热介质通过所述输送泵从所述低位罐泵出。本发明解决了使用立式长轴液下熔盐泵带来的造价、运维成本等问题,规避了大小罐或高低罐设计的安全隐患。(The invention provides a heat storage medium delivery system for a photothermal power station, comprising: the high-level tank system comprises a high-level tank for storing a heat storage medium, and is characterized by further comprising a heat storage medium transmission subsystem; the high-position tank system is connected with the heat storage medium transmission subsystem; the heat storage medium transfer subsystem comprises a low-level tank; the installation height of the low-level tank is lower than that of the high-level tank; the volume of the low-level tank is smaller than that of the high-level tank; the heat storage medium can partially or completely enter the low-level tank from the high-level tank by means of self gravity, a delivery pump is arranged on the low-level tank, and the heat storage medium is pumped out of the low-level tank through the delivery pump. The invention solves the problems of manufacturing cost, operation and maintenance cost and the like caused by using a vertical long-shaft submerged molten salt pump, and avoids the potential safety hazard of large and small tanks or high and low tanks.)

1. A heat storage medium delivery system for a photothermal power station comprising: the high-level tank system comprises a high-level tank for storing a heat storage medium, and is characterized by further comprising a heat storage medium transmission subsystem;

the high-position tank system is connected with the heat storage medium transmission subsystem;

the heat storage medium transfer subsystem comprises a low-level tank; the installation height of the low-level tank is lower than that of the high-level tank; the volume of the low-level tank is smaller than that of the high-level tank; the heat storage medium can partially or completely enter the low-level tank from the high-level tank by means of self gravity, a delivery pump is arranged on the low-level tank, and the heat storage medium is pumped out of the low-level tank through the delivery pump.

2. The system of claim 1, wherein the thermal storage medium delivery subsystem further comprises: an uninterrupted compressed gas source;

the uninterrupted compressed gas source is communicated with the gas phase space of the low-level tank through a gas source pipeline, and the gas source pipeline forms a first pipeline;

the uninterrupted compressed gas source charges air to the low-level tank, and the air pressure in the low-level tank is increased to reduce the liquid level of the heat storage medium in the low-level tank.

3. The system of claim 2, wherein the thermal storage medium delivery subsystem further comprises: a first valve assembly;

the first valve component is used for adjusting the inflation quantity of the uninterrupted compressed gas source for the low-level tank;

the first valve component is arranged on the first pipeline.

4. The system of claim 3,

the first valve assembly includes: two valve groups connected in parallel; each valve set comprises three valves in series: two check valves and an inlet regulating valve disposed between the two check valves.

5. The system of claim 2 or 3, wherein the thermal storage medium delivery subsystem further comprises: a second valve component;

the second valve assembly increases the level of the heat storage medium in the lower tank by reducing the pressure of the gas in the lower tank;

the low-level tank is provided with a first gas discharge pipeline which forms a second pipeline;

the second valve assembly is disposed on the second pipeline.

6. The system of claim 5,

the second valve assembly comprises two valve groups in parallel; each valve set comprises two valves in series: an exhaust regulating valve and a check valve.

7. The system of claim 2, wherein the thermal storage medium transport subsystem further comprises: a low tank level sensor;

the low-level tank liquid level sensor is installed on the low-level tank and used for detecting the liquid level of the heat storage medium in the low-level tank.

8. The system of claim 1, wherein the thermal storage medium delivery subsystem further comprises: a high and low tank isolation valve;

a first pipeline is arranged between the high-level tank and the low-level tank, the high-level tank is connected with the low-level tank through the first pipeline, and the first pipeline between the high-level tank and the low-level tank forms a third pipeline; and the high-low tank isolation valve is arranged on the third pipeline.

9. The system of claim 2, wherein the thermal storage medium delivery subsystem further comprises: a temperature regulator;

the uninterrupted compressed gas source is connected with the inlet of the temperature regulator through a pipeline, and a connecting pipeline between the uninterrupted compressed gas source and the inlet of the temperature regulator forms a fourth pipeline.

10. The system of claim 9, wherein the thermal storage medium delivery subsystem further comprises: a heater; the heater is located on the fourth pipeline.

11. The system of claim 9, wherein the thermal storage medium delivery subsystem further comprises: an air pressure regulating valve;

the outlet of the temperature regulator is connected with a second gas discharge pipeline, and the air pressure regulating valve is arranged on the second gas discharge pipeline.

12. The system of claim 9, wherein the thermal storage medium delivery subsystem further comprises: a temperature sensor; the temperature sensor is mounted on the temperature regulator.

13. The system of claim 8,

the thermal storage medium transfer subsystem further comprises: a flexible connector;

the flexible connector is arranged on the third pipeline and is positioned between the low-level tank and the high-level tank isolation valve.

14. The system of claim 9,

the thermal storage medium transfer subsystem further comprises a fourth valve assembly;

the fourth valve assembly is used for regulating the gas quantity and the flow rate entering the temperature regulator;

the fourth valve component is arranged on the fourth pipeline.

15. The system of claim 14,

the fourth valve assembly comprises: one regulating valve and one check valve.

16. The system of claim 5,

the heat storage medium transfer subsystem further comprises a third valve assembly;

when the first and second lines share a portion of the conduit, the third valve assembly is disposed on the shared conduit.

17. The system of claim 1, wherein the thermal storage medium delivery subsystem further comprises: a transfer pump outlet recirculation valve; wherein:

a second pipeline is arranged between the high-level tank and the low-level tank; one end of the second pipeline is connected with the inlet of the high-level tank, and the other end of the second pipeline is connected with the outlet of the conveying pump; the second pipeline forms a fifth pipeline, and heat storage medium can be pumped into the high-level tank from the low-level tank along the fifth pipeline; and the conveying pump outlet recirculation valve is arranged on the fifth pipeline.

18. A heat storage medium delivery system for a photothermal power station comprising: the high-level tank system, the heat storage medium heat absorption subsystem and the heat storage medium heat exchange subsystem;

the high-position tank system comprises: a high-temperature heat storage medium high-level tank for storing a high-temperature heat storage medium and/or a low-temperature heat storage medium high-level tank for storing a low-temperature heat storage medium,

the system also comprises a heat storage medium transmission subsystem, wherein the heat storage medium transmission subsystem comprises a high-temperature heat storage medium transmission subsystem and/or a low-temperature heat storage medium transmission subsystem;

the high-position tank system is connected with the heat storage medium transmission subsystem;

the high-temperature heat storage medium transmission subsystem is arranged corresponding to the high-temperature heat storage medium high-level tank; the high-temperature heat storage medium transmission subsystem comprises a high-temperature heat storage medium low-level tank;

the installation height of the high-temperature heat storage medium low-level tank is lower than that of the high-temperature heat storage medium high-level tank; the volume of the high-temperature heat storage medium low-level tank is smaller than that of the high-temperature heat storage medium high-level tank; the high-temperature heat storage medium can partially or completely enter the high-temperature heat storage medium low-level tank from the high-temperature heat storage medium high-level tank by means of self gravity;

a high-temperature heat storage medium delivery pump is arranged on the high-temperature heat storage medium low-level tank; the outlet of the high-temperature heat storage medium delivery pump is respectively connected with the heat storage medium heat exchange subsystem and the high-temperature heat storage medium high-level tank; the high-temperature heat storage medium is pumped into the heat storage medium heat exchange subsystem from the high-temperature heat storage medium low-level tank;

the low-temperature heat storage medium transmission subsystem is arranged corresponding to the low-temperature heat storage medium high-level tank; the low-temperature heat storage medium transmission subsystem comprises a low-temperature heat storage medium low-level tank; the installation height of the low-temperature heat storage medium low-level tank is lower than that of the low-temperature heat storage medium high-level tank; the volume of the low-temperature heat storage medium low-level tank is smaller than that of the low-temperature heat storage medium high-level tank; the low-temperature heat storage medium can partially or completely enter the low-temperature heat storage medium low-level tank from the low-temperature heat storage medium high-level tank by means of self gravity;

a low-temperature heat storage medium delivery pump is arranged on the low-temperature heat storage medium low-level tank, and an outlet of the low-temperature heat storage medium delivery pump is respectively connected with the heat storage medium heat absorption subsystem and the low-temperature heat storage medium high-level tank; and the low-temperature heat storage medium is pumped into the heat storage medium heat absorption subsystem from the low-temperature heat storage medium low-level tank.

Technical Field

The invention belongs to the field of solar thermal power generation, and particularly relates to a heat storage medium conveying system for a photo-thermal power station.

Background

Solar energy utilization modes are various and comprise technical categories such as photovoltaic power generation and photo-thermal power generation. The solar photo-thermal power generation is divided into a groove type, a tower type, a butterfly type and a linear Fresnel from the difference of the structural forms of a condenser lens surface and a heat collector.

The solar photo-thermal technology is expected to be separate from a plurality of power generation technologies, and finally, the cost can be greatly broken through, at least two problems need to be solved, one is the reliability problem of equipment, and the other is the optimization of the system structure through the improvement of the process and the reduction of the equipment investment.

No matter the photo-thermal power station based on groove type, tower type, butterfly type or linear Fresnel technology, the heat storage medium adopted at present is binary molten nitrate (60% NaNO)₃+40％KNO₃) A large vertical vault storage tank is used as a storage container of a heat storage medium, and a vertical long-shaft submerged molten salt pump installed on the top of the storage tank is used as a conveying pump. However, due to the use limitation of the vertical long-axis submerged molten salt pump, two problems are caused: one of the problems is that due to the use limitation of the vertical long-shaft submerged molten salt pump, a large amount of molten salt cannot be used in each of the high-temperature molten salt storage tank and the low-temperature molten salt storage tank, the purchase cost and the manufacturing cost of the molten salt are increased, the amount of the unusable molten salt is about 6000t according to a 100MW heat storage 12 h-scale tower type photo-thermal power station, the height of each molten salt storage tank is increased by 1m, and the cost expenditure is as much as 2000 to 3000 ten thousand; the second problem is that the design and manufacturing difficulty of the vertical long-shaft submerged molten salt pump is high, manufacturers capable of producing long-shaft molten salt pumps for tower-type solar power stations in the world at present can have a few fingers, the price is high, the supply period is long, in addition, the shaft of the vertical long-shaft submerged pump is composed of multiple stages and is as long as 16m to 18m, the assembling and hoisting requirements are high, the bearing bush positioned at the submerged part needs to be replaced periodically, the one-time maintenance time can be as long as half a month, the potential operation and maintenance cost and the operation risk are high, and the development of the solar photo-thermal power generation industry is not facilitated.

Although some solutions have been proposed, such as using a large tank design and a small tank with a molten salt pump, the safety problems of the small tank, such as the liquid level control of the small tank, the liquid full problem of the small tank once the sealing fails, such as the thermal stress between the large tank and the small tank, have not been solved satisfactorily. Therefore, even if the proposal is provided, the proposal is not adopted (not adopted in the first photo-thermal power generation demonstration project in China).

The Chinese patent with the publication number of CN103292485B discloses a fused salt heat storage and exchange system for solar thermal power generation, which comprises a fused salt heat storage system and a fused salt exchange system, wherein the fused salt heat storage system comprises a low-temperature storage tank and a high-temperature storage tank, a pipeline at the bottom of the low-temperature storage tank is provided with a low-temperature fused salt pump for adjusting the flow of fused salt entering a solar heater, and the bottom of the high-temperature storage tank is provided with a high-temperature fused salt pump for adjusting the flow of the fused salt entering the heat exchange system; the low-temperature molten salt pump and the high-temperature molten salt pump are both horizontally mounted at the bottom of the tank, and the mounting positions of the low-temperature molten salt pump and the high-temperature molten salt pump are lower than the ground plane; the equipment of the molten salt heat exchange system adopts a snakelike heat exchange tube structure.

Although the invention avoids the use of a vertical long-shaft submerged molten salt pump, the invention does not solve the problem of cost rise caused by large amount of unavailable salt and does not eliminate unsafe factors caused by combination of high-level tanks and low-level tanks.

Therefore, a stable solution is found, the problems of cost increase and potential operation safety risk caused by a vertical long-shaft submerged molten salt pump can be properly solved, and potential safety hazards in the design of large and small tanks or high and low tanks can be avoided, so that the problem to be solved by the patent is solved.

Disclosure of Invention

In view of the deficiencies in the prior art, it is an object of the present invention to provide a heat storage medium delivery system for a photothermal power station. The technical scheme of the invention is as follows:

a heat storage medium delivery system for a photothermal power station comprising: the high-position tank system comprises a high-position tank for storing heat storage media and a heat storage media transmission subsystem;

the high-position tank system is connected with the heat storage medium transmission subsystem;

the heat storage medium transfer subsystem comprises a low-level tank; the installation height of the low-level tank is lower than that of the high-level tank; the volume of the low-level tank is smaller than that of the high-level tank; the heat storage medium can partially or completely enter the low-level tank from the high-level tank by means of self gravity, a delivery pump is arranged on the low-level tank, and the heat storage medium is pumped out of the low-level tank through the delivery pump.

Optionally, the thermal storage medium transfer subsystem further comprises: an uninterrupted compressed gas source;

the uninterrupted compressed gas source is communicated with the gas phase space of the low-level tank through a gas source pipeline, and the gas source pipeline forms a first pipeline;

the uninterrupted compressed gas source charges air to the low-level tank, and the air pressure in the low-level tank is increased to reduce the liquid level of the heat storage medium in the low-level tank.

Optionally, the thermal storage medium transfer subsystem further comprises: a first valve assembly;

the first valve component is used for adjusting the inflation quantity of the uninterrupted compressed gas source for the low-level tank;

the first valve component is arranged on the first pipeline.

Optionally, the first valve assembly comprises: two valve groups connected in parallel; each valve set comprises three valves in series: two check valves and an inlet regulating valve disposed between the two check valves.

Optionally, the thermal storage medium transfer subsystem further comprises: a second valve component;

the second valve assembly increases the level of the heat storage medium in the lower tank by reducing the pressure of the gas in the lower tank;

the low-level tank is provided with a first gas discharge pipeline which forms a second pipeline;

the second valve assembly is disposed on the second pipeline.

Optionally, the second valve assembly comprises two valve groups in parallel; each valve set comprises two valves in series: an exhaust regulating valve and a check valve.

Optionally, the thermal storage medium transfer subsystem further comprises: a low tank level sensor; the low-level tank liquid level sensor is installed on the low-level tank and used for detecting the liquid level of the heat storage medium in the low-level tank.

Optionally, the thermal storage medium transfer subsystem further comprises: a high and low tank isolation valve;

a first pipeline is arranged between the high-level tank and the low-level tank, the high-level tank is connected with the low-level tank through the first pipeline, and the first pipeline between the high-level tank and the low-level tank forms a third pipeline; and the high-low tank isolation valve is arranged on the third pipeline.

Optionally, the thermal storage medium transfer subsystem further comprises: a temperature regulator;

the uninterrupted compressed gas source is connected with the inlet of the temperature regulator through a pipeline, and a connecting pipeline between the uninterrupted compressed gas source and the inlet of the temperature regulator forms a fourth pipeline.

Optionally, the thermal storage medium transfer subsystem further comprises: a heater; the heater is located on the fourth pipeline.

Optionally, the thermal storage medium transfer subsystem further comprises: an air pressure regulating valve;

the outlet of the temperature regulator is connected with a second gas discharge pipeline, and the air pressure regulating valve is arranged on the second gas discharge pipeline.

Optionally, the thermal storage medium transfer subsystem further comprises: a temperature sensor; the temperature sensor is mounted on the temperature regulator.

Optionally, the thermal storage medium transfer subsystem further comprises: a flexible connector; the flexible connector is arranged on the third pipeline and is positioned between the low-level tank and the high-level tank isolation valve.

Optionally, the thermal storage medium transfer subsystem further comprises a fourth valve assembly; the fourth valve assembly is used for regulating the gas quantity and the flow rate entering the temperature regulator; the fourth valve component is arranged on the fourth pipeline.

Optionally, the fourth valve assembly comprises: one regulating valve and one check valve.

Optionally, the heat storage medium transfer subsystem further comprises a third valve assembly; when the first and second lines share a portion of the conduit, the third valve assembly is disposed on the shared conduit.

Optionally, the thermal storage medium transfer subsystem further comprises: a transfer pump outlet recirculation valve; wherein:

a second pipeline is arranged between the high-level tank and the low-level tank; one end of the second pipeline is connected with the inlet of the high-level tank, and the other end of the second pipeline is connected with the outlet of the conveying pump; the second pipeline forms a fifth pipeline, and heat storage medium can be pumped into the high-level tank from the low-level tank along the fifth pipeline; and the conveying pump outlet recirculation valve is arranged on the fifth pipeline.

A heat storage medium delivery system for a photothermal power station comprising: the system comprises a high-level tank system, a heat storage medium heat absorption subsystem, a heat storage medium heat exchange subsystem and a heat storage medium transmission subsystem;

the high-position tank system comprises: the high-temperature heat storage medium high-level tank is used for storing a high-temperature heat storage medium and/or the low-temperature heat storage medium high-level tank is used for storing a low-temperature heat storage medium;

the heat storage medium transmission subsystem comprises a high-temperature heat storage medium transmission subsystem and/or a low-temperature heat storage medium transmission subsystem;

the high-position tank system is connected with the heat storage medium transmission subsystem; the high-temperature heat storage medium transmission subsystem is arranged corresponding to the high-temperature heat storage medium high-level tank; the high-temperature heat storage medium transmission subsystem comprises a high-temperature heat storage medium low-level tank;

the installation height of the high-temperature heat storage medium low-level tank is lower than that of the high-temperature heat storage medium high-level tank; the volume of the high-temperature heat storage medium low-level tank is smaller than that of the high-temperature heat storage medium high-level tank; the high-temperature heat storage medium can partially or completely enter the high-temperature heat storage medium low-level tank from the high-temperature heat storage medium high-level tank by means of self gravity, and a high-temperature heat storage medium delivery pump is arranged on the high-temperature heat storage medium low-level tank;

the outlet of the high-temperature heat storage medium delivery pump is respectively connected with the heat storage medium heat exchange subsystem and the high-temperature heat storage medium high-level tank; the high-temperature heat storage medium is pumped into the heat storage medium heat exchange subsystem from the high-temperature heat storage medium low-level tank;

the low-temperature heat storage medium transmission subsystem is arranged corresponding to the low-temperature heat storage medium high-level tank; the low-temperature heat storage medium transmission subsystem comprises a low-temperature heat storage medium low-level tank; the installation height of the low-temperature heat storage medium low-level tank is lower than that of the low-temperature heat storage medium high-level tank; the volume of the low-temperature heat storage medium low-level tank is smaller than that of the low-temperature heat storage medium high-level tank; the low-temperature heat storage medium can partially or completely enter the low-temperature heat storage medium low-level tank from the low-temperature heat storage medium high-level tank by means of self gravity, a low-temperature heat storage medium delivery pump is arranged on the low-temperature heat storage medium low-level tank,

the outlet of the low-temperature heat storage medium delivery pump is respectively connected with the heat storage medium heat absorption subsystem and the low-temperature heat storage medium high-level tank; and the low-temperature heat storage medium is pumped into the heat storage medium heat absorption subsystem from the low-temperature heat storage medium low-level tank.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention solves the problems of high cost, high design and manufacturing difficulty, high failure rate and frequent maintenance caused by adopting a long-shaft molten salt pump in a conventional solar power station and the problem of cost rise caused by large quantity of unavailable heat storage media through the design of the high-low tank.

2. The invention ensures the operation safety of the high-level tank and the low-level tank by designing a set of compressed gas liquid level regulating system and a set of anti-fault leakage system and adopting a flexible connector technology, and eliminates unsafe factors caused by the combination of the high-level tank and the low-level tank.

3. The invention ensures that the thermal stress between the low-temperature heat storage medium high-level tank and/or the high-temperature heat storage medium high-level tank and the corresponding low-level tank is fully released through the flexible connector, thereby ensuring the intrinsic safety (because the heat storage medium storage tank can generate larger thermal expansion displacement when the cold and hot state changes in the operation process).

4. The invention uses the uninterrupted compressed gas source, the temperature regulator, the air pressure regulating valve, the high-low tank isolating valve, the temperature sensor and the connecting pipelines among the high-low tank isolating valve and the temperature sensor to form the fault leakage prevention system of the system, and the fault leakage prevention system ensures the safe isolation when the isolation is needed, such as when the low tank needs to be maintained, the flexible connector needs to be replaced, and the uninterrupted compressed gas source fails.

5. The fourth pipeline is provided with a heater. When the solidified heat storage medium on the third pipeline needs to be unfrozen, the heater heats the gas sent into the temperature regulator by the uninterrupted gas source, and the time for unfreezing the solidified heat storage medium on the third pipeline is saved.

6. The fourth valve component is adopted on the fourth pipeline, so that on one hand, the gas pressure in the temperature regulator can be controlled, and on the other hand, the effect of regulating the cooling or melting speed is achieved; in addition, when the temperature regulator 8 has a leakage failure, the pressure of the gas side can be controlled to be higher than that of the heat storage medium side, thereby preventing the heat storage medium from leaking outside.

7. The invention takes the uninterrupted compressed gas source, the first valve component and the second valve component as the compressed gas liquid level regulating system of the system, thereby ensuring that the liquid level of the low-level tank can be freely regulated in the operation process.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic view of a heat storage medium delivery system for a photothermal power plant in accordance with a first embodiment of the present invention;

FIG. 2 is a schematic view of a heat storage medium delivery system for a photothermal power plant in accordance with a second embodiment of the present invention;

FIG. 3 is a schematic view of a heat storage medium delivery system for a photothermal power station according to a third embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The first embodiment:

as shown in fig. 1, the present embodiment discloses a heat storage medium delivery system for a photothermal power station, comprising: the high-level tank system comprises a high-level tank 1 for storing a heat storage medium and a heat storage medium transmission subsystem; the high-level tank system is connected with the heat storage medium transmission subsystem.

In this embodiment, the heat storage medium is a molten salt, which is only an example, and the present invention does not limit the specific heat storage medium. The high-level tank is a molten salt storage tank.

The heat storage medium transmission subsystem comprises a low-level tank 2 and an uninterrupted compressed gas source 3;

the installation height of the low-level tank 2 is lower than that of the high-level tank 1; the volume of the low-level tank 2 is smaller than that of the high-level tank 1; the heat storage medium can partially or completely enter the low-level tank from the high-level tank by means of self gravity, a delivery pump 4 is arranged on the low-level tank, and the heat storage medium is pumped out of the low-level tank through the delivery pump.

The uninterrupted compressed gas source is communicated with the gas phase space of the low-level tank through a gas source pipeline, and the gas source pipeline forms a first pipeline; the uninterrupted compressed gas source charges air to the low-level tank, and the air pressure in the low-level tank is increased to reduce the liquid level of the heat storage medium in the low-level tank.

In this embodiment, the transfer pump is a molten salt pump, and the uninterrupted compressed gas source 3 is a buffer gas storage tank. The gas in the buffer gas storage tank can be air, or gas which does not react with the heat storage medium except air, such as nitrogen. The present invention is not limited to specific gas species.

Wherein the thermal storage medium transfer subsystem further comprises: first valve component 51, second valve component 52, third valve component 53.

The first valve component is used for adjusting the inflation quantity of the uninterrupted compressed gas source for the low-level tank; the first valve assembly 51 is disposed on the first pipeline. When the liquid level of the low-level tank is high, the first valve component is opened to prevent the liquid level of the low-level tank from being too high.

In this embodiment, the first valve assembly comprises: two valve groups connected in parallel; each valve set comprises three valves in series: two check valves and an intake air regulating valve 511 disposed between the two check valves.

The second valve assembly 52 increases the level of the heat storage medium in the lower tank by reducing the pressure of the gas in the lower tank; the lower tank is provided with a first gas discharge conduit 522 forming a second conduit; the second valve assembly is disposed on the second pipeline. When the liquid level of the low-level tank is low, the second valve component is opened, so that the liquid level of the low-level tank is prevented from being too low. In this embodiment, the outlet height of the first gas discharge pipe 522 is the same height as the highest liquid level of the high-level tank 1.

It should be noted that if the uninterrupted compressed gas source 3 provides air, the outlet of the first gas discharge pipe 522 may be directly connected to the atmosphere. If the uninterrupted compressed gas source 3 provides a gas other than air, such as nitrogen, then the outlet of the first gas discharge pipe 522 may be connected to a gas recovery device, which may also be considered to be a gas that is returned to the uninterrupted compressed gas source 3, in order to take into account the problem of recovering the relevant gas.

In this embodiment, the second valve assembly comprises two valve groups in parallel; each valve set comprises two valves in series: an exhaust regulating valve 521, a check valve.

When the first and second lines share a portion of the conduit, the third valve assembly 53 is disposed on the shared conduit. In this embodiment, third valve assembly 53 comprises a check valve.

Wherein the thermal storage medium transfer subsystem further comprises: the device comprises a low-level tank liquid level sensor 6, a high-level tank isolation valve 7, a temperature regulator 8, a heater 9, an air pressure regulating valve 10, a temperature sensor 11, a fourth valve component 54 and a flexible connector 12.

In this embodiment, the temperature regulator 8 is an air cooling/heating device. The heater 9 is an electric heater.

The low-level tank liquid level sensor 6 is installed on the low-level tank 2 and used for detecting the liquid level of the heat storage medium in the low-level tank 2. When the low-level tank liquid level sensor 6 sends a low-level alarm, the liquid level of the low-level tank 2 is increased by opening the second valve component 52 to be at the normal operation liquid level; when the low tank level sensor 6 gives a high level alarm, the level of the low tank 2 is lowered to a normal operating level by opening the first valve assembly 51.

A first pipeline is arranged between the high-level tank 1 and the low-level tank 2, the high-level tank 1 is connected with the low-level tank 2 through the first pipeline, and the first pipeline between the high-level tank 1 and the low-level tank forms a third pipeline; and the high-low tank isolation valve 7 is arranged on the third pipeline. Once the low-level tank 2 is in fault and needs to be shut down for maintenance, the flow of the heat storage medium between the high-level tank 1 and the low-level tank 2 is cut off through the high-level tank isolation valve 7, and then compressed air is introduced into the temperature regulator 8 to freeze the heat storage medium, so that the flow of the heat storage medium between the high-level tank 1 and the low-level tank 2 is further cut off.

The uninterrupted compressed gas source 3 is connected with the inlet of the temperature regulator 8 through a pipeline, and a connecting pipeline between the uninterrupted compressed gas source and the temperature regulator forms a fourth pipeline. The heater 9 is located on the fourth line. The outlet of the temperature regulator 8 is connected with a second gas discharge pipeline, and the air pressure regulating valve 10 is arranged on the second gas discharge pipeline. The temperature sensor 11 is mounted on the temperature regulator 8.

The fourth valve assembly 54 is used to regulate the amount and flow rate of gas into the temperature regulator 8; the fourth valve assembly is arranged on the fourth pipeline and is positioned between the heater 9 and the uninterrupted compressed gas source 3. Meanwhile, the fourth valve assembly 54 is used for controlling the air pressure in the temperature regulator 8, and on the one hand, plays a role in regulating the cooling speed; on the other hand, when the heat storage medium side line in the temperature regulator 8 has a leakage failure, the pressure on the gas side in the temperature regulator 8 can be controlled to be higher than the pressure on the heat storage medium side, thereby preventing the heat storage medium from leaking outside.

In this embodiment, the fourth valve assembly 54 includes: one regulating valve and one check valve.

The flexible connector 12 is arranged on the third pipeline and is positioned between the low-level tank 2 and the high-level and low-level tank isolation valves. The flexible connector 12 may be a corrugated tube, and functions to realize flexible connection between the high-level tank 1 and the low-level tank 2, and reduce thermal stress between the high-level tank and the low-level tank when the high-level tank 1 expands with heat and contracts with cold due to temperature change.

Wherein the thermal storage medium transfer subsystem further comprises: a transfer pump outlet recirculation valve 13; wherein:

a second pipeline is arranged between the high-level tank and the low-level tank; one end of the second pipeline is connected with the inlet of the high-level tank, and the other end of the second pipeline is connected with the outlet of the conveying pump; the second pipeline forms a fifth pipeline, and heat storage medium can be pumped into the high-level tank from the low-level tank along the fifth pipeline; the transfer pump outlet recirculation valve 13 is arranged on the fifth line.

The delivery pump 4 is installed on the low-level tank 2, and has the function of sending out the molten salt in the low-level tank 2, on one hand, the molten salt returns to the high-level tank 1 through a fifth pipeline, and on the other hand, the molten salt is delivered to the outside through a pipeline. Because the height and the volume of the low-level tank are very small relative to the high-level tank, the equipment cost can be reduced and the system reliability can be improved relative to the use of the long-axis submerged molten salt pump, and because the installation height of the low-level tank is lower than that of the high-level tank, the amount of the molten salt which cannot be utilized due to the use of the long-axis submerged molten salt pump in the high-level tank can be reduced.

When the low-level tank 2 needs to cut off the flow of the molten salt between the low-level tank and the high-level tank 1, the high-level tank isolation valve 7 is closed to cut off the rapid flow of the molten salt, and then the uninterrupted compressed gas source 3 sends compressed gas into the temperature regulator 8 through the gas source pipeline. In the process, the heater 9 does not work, the fourth valve assembly 54 adjusts the amount and flow rate of gas entering the temperature regulator 8, the molten salt in a section of connecting pipeline between the high-level tank 1 and the low-level tank 2 is cooled through convection heat transfer, the molten salt in the section of connecting pipeline is completely solidified and does not flow, the temperature of the molten salt pipeline of the cooled part is adjusted through the air pressure adjusting valve 10, the opening degree of the air pressure adjusting valve 10 is related to the temperature of the temperature sensor 11 installed on the molten salt pipeline of the cooled part, the temperature of the temperature sensor 11 is controlled not to exceed the solidification temperature of the molten salt, and the molten salt is ensured not to be molten.

When molten salt flow needs to be restarted between the low-level tank 2 and the high-level tank 1, the high-level tank isolation valve 7 is opened, then compressed gas is sent into the temperature regulator 8 from the uninterrupted compressed gas source 3 through the gas source pipeline, and the fourth valve assembly regulates the gas quantity and the flow rate entering the temperature regulator 8. And in the process, the heater 9 is operated so that it heats the gas fed into the temperature regulator 8. The heated gas enters a temperature regulator, and molten salt in a section of connecting pipeline between the high-level tank 1 and the low-level tank 2 is heated through convection heat transfer, so that the molten salt in the section of pipeline is melted and flows.

Second embodiment

FIG. 2 is a schematic view of a second embodiment of the invention, disclosing a heat storage medium delivery system for a photothermal power station, comprising: the high-level tank system comprises a high-level tank 1 for storing a heat storage medium and a heat storage medium transmission subsystem; the high-level tank system is connected with the heat storage medium transmission subsystem.

In this embodiment, the heat storage medium is a molten salt, which is only an example, and the present invention does not limit the specific heat storage medium. The high-level tank is a molten salt storage tank.

The heat storage medium transmission subsystem comprises a low-level tank 2 and an uninterrupted compressed gas source 3;

the installation height of the low-level tank 2 is lower than that of the high-level tank 1; the volume of the low-level tank 2 is smaller than that of the high-level tank 1; the heat storage medium can partially or completely enter the low-level tank from the high-level tank by means of self gravity, a delivery pump 4 is arranged on the low-level tank, and the heat storage medium is pumped out of the low-level tank through the delivery pump.

The uninterrupted compressed gas source is communicated with the gas phase space of the low-level tank through a gas source pipeline, and the gas source pipeline forms a first pipeline; the uninterrupted compressed gas source charges air to the low-level tank, and the air pressure in the low-level tank is increased to reduce the liquid level of the heat storage medium in the low-level tank.

In this embodiment, the transfer pump is a molten salt pump, and the uninterrupted compressed gas source 3 is a buffer gas storage tank. The gas in the buffer gas storage tank can be air, or gas which does not react with the heat storage medium except air, such as nitrogen. The present invention is not limited to specific gas species.

Wherein the thermal storage medium transfer subsystem further comprises: first valve component 51, second valve component 52, third valve component 53.

The first valve component is used for adjusting the inflation quantity of the uninterrupted compressed gas source for the low-level tank; the first valve assembly 51 is disposed on the first pipeline. When the liquid level of the low-level tank is high, the first valve component is opened to prevent the liquid level of the low-level tank from being too high.

In this embodiment, the first valve assembly 51 includes only one inlet regulator valve.

The second valve assembly 52 increases the level of the heat storage medium in the lower tank by reducing the pressure of the gas in the lower tank; the lower tank is provided with a first gas discharge conduit 522 forming a second conduit; the second valve assembly is disposed on the second pipeline. When the liquid level of the low-level tank is low, the second valve component is opened, so that the liquid level of the low-level tank is prevented from being too low. In this embodiment, the outlet height of the first gas discharge pipe 522 is the same height as the highest liquid level of the high-level tank 1.

It should be noted that if the uninterrupted compressed gas source 3 provides air, the outlet of the first gas discharge pipe 522 may be directly connected to the atmosphere. If the uninterrupted compressed gas source 3 provides a gas other than air, such as nitrogen, then the outlet of the first gas discharge pipe 522 may be connected to a gas recovery device, which may also be considered to be a gas that is returned to the uninterrupted compressed gas source 3, in order to take into account the problem of recovering the relevant gas.

In this embodiment, second valve assembly 52 includes only one exhaust regulator valve.

When the first and second lines share a portion of the conduit, the third valve assembly 53 is disposed on the shared conduit. In this embodiment, third valve assembly 53 comprises a check valve.

Wherein the thermal storage medium transfer subsystem further comprises: a low-level tank liquid level sensor 6, a high-level tank isolation valve 7, a temperature regulator 8, a heater 9, an air pressure regulating valve 10, a temperature sensor 11 and a fourth valve component 54.

In this embodiment, the temperature regulator 8 is an air cooling/heating device. The heater 9 is an electric heater.

The low-level tank liquid level sensor 6 is installed on the low-level tank 2 and used for detecting the liquid level of the heat storage medium in the low-level tank 2. When the low-level tank liquid level sensor 6 sends a low-level alarm, the liquid level of the low-level tank 2 is increased by opening the second valve component 52 to be at the normal operation liquid level; when the low tank level sensor 6 gives a high level alarm, the level of the low tank 2 is lowered to a normal operating level by opening the first valve assembly 51.

A first pipeline is arranged between the high-level tank 1 and the low-level tank 2, the high-level tank 1 is connected with the low-level tank 2 through the first pipeline, and the first pipeline between the high-level tank 1 and the low-level tank forms a third pipeline; and the high-low tank isolation valve 7 is arranged on the third pipeline. Once the low-level tank 2 is in fault and needs to be shut down for maintenance, the flow of the heat storage medium between the high-level tank 1 and the low-level tank 2 is cut off through the high-level tank isolation valve 7, and then compressed air is introduced into the temperature regulator 8 to freeze the heat storage medium, so that the flow of the heat storage medium between the high-level tank 1 and the low-level tank 2 is further cut off.

The uninterrupted compressed gas source 3 is connected with the inlet of the temperature regulator 8 through a pipeline, and a connecting pipeline between the uninterrupted compressed gas source and the temperature regulator forms a fourth pipeline. The heater 9 is located on the fourth line. The outlet of the temperature regulator 8 is connected with a second gas discharge pipeline, and the air pressure regulating valve 10 is arranged on the second gas discharge pipeline. The temperature sensor 11 is mounted on the temperature regulator 8.

The fourth valve assembly 54 is used to regulate the amount and flow rate of gas into the temperature regulator 8; the fourth valve assembly is arranged on the fourth pipeline and is positioned between the heater 9 and the uninterrupted compressed gas source 3. Meanwhile, the fourth valve assembly 54 is used for controlling the air pressure in the temperature regulator 8, and on the one hand, plays a role in regulating the cooling speed; on the other hand, when the heat storage medium side line in the temperature regulator 8 has a leakage failure, the pressure on the gas side in the temperature regulator 8 can be controlled to be higher than the pressure on the heat storage medium side, thereby preventing the heat storage medium from leaking outside.

In this embodiment, the fourth valve assembly 54 includes only one air flow regulator valve.

Wherein the thermal storage medium transfer subsystem further comprises: a transfer pump outlet recirculation valve 13; wherein:

a second pipeline is arranged between the high-level tank and the low-level tank; one end of the second pipeline is connected with the inlet of the high-level tank, and the other end of the second pipeline is connected with the outlet of the conveying pump; the second pipeline forms a fifth pipeline, and heat storage medium can be pumped into the high-level tank from the low-level tank along the fifth pipeline; the transfer pump outlet recirculation valve 13 is arranged on the fifth line.

The delivery pump 4 is installed on the low-level tank 2, and has the function of sending out the molten salt in the low-level tank 2, on one hand, the molten salt returns to the high-level tank 1 through a fifth pipeline, and on the other hand, the molten salt is delivered to the outside through a pipeline. Because the height and the volume of the low-level tank are very small relative to the high-level tank, the equipment cost can be reduced and the system reliability can be improved relative to the use of the long-axis submerged molten salt pump, and because the installation height of the low-level tank is lower than that of the high-level tank, the amount of the molten salt which cannot be utilized due to the use of the long-axis submerged molten salt pump in the high-level tank can be reduced.

When the low-level tank 2 needs to cut off the flow of the molten salt between the low-level tank and the high-level tank 1, the high-level tank isolation valve 7 is closed to cut off the rapid flow of the molten salt, and then the uninterrupted compressed gas source 3 sends compressed gas into the temperature regulator 8 through the gas source pipeline. In the process, the heater 9 does not work, the fourth valve assembly 54 adjusts the amount and flow rate of gas entering the temperature regulator 8, the molten salt in a section of connecting pipeline between the high-level tank 1 and the low-level tank 2 is cooled through convection heat transfer, the molten salt in the section of connecting pipeline is completely solidified and does not flow, the temperature of the molten salt pipeline of the cooled part is adjusted through the air pressure adjusting valve 10, the opening degree of the air pressure adjusting valve 10 is related to the temperature of the temperature sensor 11 installed on the molten salt pipeline of the cooled part, the temperature of the temperature sensor 11 is controlled not to exceed the solidification temperature of the molten salt, and the molten salt is ensured not to be molten.

When molten salt flow needs to be restarted between the low-level tank 2 and the high-level tank 1, the high-level tank isolation valve 7 is opened, then compressed gas is sent into the temperature regulator 8 from the uninterrupted compressed gas source 3 through the gas source pipeline, and the fourth valve assembly regulates the gas quantity and the flow rate entering the temperature regulator 8. And in the process, the heater 9 is operated so that it heats the gas fed into the temperature regulator 8. The heated gas enters a temperature regulator, and molten salt in a section of connecting pipeline between the high-level tank 1 and the low-level tank 2 is heated through convection heat transfer, so that the molten salt in the section of pipeline is melted and flows.

The second embodiment differs from the first embodiment in that:

the first valve assembly includes only one inlet regulator valve; the second valve assembly includes only one exhaust gas regulating valve; the fourth valve assembly includes only one air flow regulator valve; the third pipeline is not provided with a flexible connector.

Third embodiment

Referring to fig. 3, a third embodiment of the invention discloses a heat storage medium delivery system for a photothermal power station comprising: the system comprises a high-level tank system, a heat storage medium heat absorption subsystem 500, a heat storage medium heat exchange subsystem 600 and a heat storage medium transmission subsystem.

The high-position tank system comprises: a high-temperature heat storage medium high-level tank 120 for storing a high-temperature heat storage medium and/or a low-temperature heat storage medium high-level tank 110 for storing a low-temperature heat storage medium. The heat storage medium transmission subsystem comprises a high-temperature heat storage medium transmission subsystem and/or a low-temperature heat storage medium transmission subsystem; the high-level tank system is connected with the heat storage medium transmission subsystem.

In this embodiment, the high-position tank system includes: a high-temperature heat storage medium high-level tank 120 for storing a high-temperature heat storage medium, and a low-temperature heat storage medium high-level tank 110 for storing a low-temperature heat storage medium. The heat storage medium transmission subsystem comprises a high-temperature heat storage medium transmission subsystem and a low-temperature heat storage medium transmission subsystem.

It should be noted that, in specific implementation, the high-level tank system may only include a high-temperature heat storage medium high-level tank or a low-temperature heat storage medium high-level tank, and correspondingly, the heat storage medium transmission subsystem may only include a high-temperature heat storage medium transmission subsystem or a low-temperature heat storage medium transmission subsystem. That is, the delivery system of the present invention is used only in terms of high-temperature heat storage medium delivery, or only in terms of low-temperature heat storage medium delivery. The present invention is not limited to the above.

The high-temperature heat storage medium transmission subsystem is arranged corresponding to the high-temperature heat storage medium high-level tank 120; the high temperature heat storage medium transfer subsystem includes a high temperature heat storage medium low-level tank 220.

The installation height of the high-temperature heat storage medium low-level tank 220 is lower than that of the high-temperature heat storage medium high-level tank 120; the volume of the high-temperature heat storage medium low-level tank 220 is smaller than that of the high-temperature heat storage medium high-level tank 120; the high-temperature heat storage medium can partially or completely enter the high-temperature heat storage medium low-level tank 220 from the high-temperature heat storage medium high-level tank 120 by means of self gravity, and a high-temperature heat storage medium delivery pump 420 is arranged on the high-temperature heat storage medium low-level tank 220.

The outlet of the high-temperature heat storage medium delivery pump 420 is respectively connected with the heat storage medium heat exchange subsystem 600 and the high-temperature heat storage medium high-level tank 120; the high temperature heat storage medium is pumped from the high temperature heat storage medium low tank 220 into the heat storage medium heat exchange subsystem 600.

The low-temperature heat storage medium transmission subsystem is arranged corresponding to the low-temperature heat storage medium high-level tank 110; the low-temperature heat storage medium transmission subsystem comprises a low-temperature heat storage medium low-level tank 210; the installation height of the low-temperature heat storage medium low-level tank 210 is lower than that of the low-temperature heat storage medium high-level tank 110; the volume of the low-temperature heat storage medium low-level tank 210 is smaller than that of the low-temperature heat storage medium high-level tank 110; the low-temperature heat storage medium can partially or completely enter the low-temperature heat storage medium low-level tank 210 from the low-temperature heat storage medium high-level tank 110 by means of self gravity, a low-temperature heat storage medium delivery pump 410 is arranged on the low-temperature heat storage medium low-level tank 210, and the outlet of the low-temperature heat storage medium delivery pump 410 is respectively connected with the heat storage medium heat absorption subsystem 500 and the low-temperature heat storage medium high-level tank 110; the low-temperature heat storage medium is pumped from the low-temperature heat storage medium low-level tank 210 into the heat storage medium heat absorption subsystem 500.

The high temperature heat storage medium delivery subsystem further comprises an uninterrupted compressed gas source 300. In this embodiment, the high-temperature heat storage medium is high-temperature molten salt, the high-temperature heat storage medium delivery pump 420 is a molten salt pump, and the uninterrupted compressed gas source 300 is a buffer gas storage tank. The gas in the buffer gas storage tank can be air, or gas which does not react with the molten salt, such as nitrogen, and the like besides the air. The present invention is not limited to specific gas species.

The uninterrupted compressed gas source 300 is communicated with the gas phase space of the high-temperature heat storage medium low-level tank 220 through a gas source pipeline, and the gas source pipeline forms a first high-temperature heat storage medium pipeline; the uninterrupted compressed gas source 300 increases the pressure in the high temperature heat storage medium low-level tank 220 by charging gas into the high temperature heat storage medium low-level tank 220 to reduce the liquid level of the heat storage medium in the high temperature heat storage medium low-level tank 220.

Wherein, the high temperature heat storage medium transmission subsystem still includes: a high temperature heat storage medium first valve component 241, a high temperature heat storage medium second valve component 242, and a high temperature heat storage medium third valve component 243.

The high temperature heat storage medium first valve component 241 is used for adjusting the gas charging quantity provided by the uninterrupted compressed gas source for the high temperature heat storage medium low tank 220; the high temperature heat storage medium first valve assembly 241 is disposed on the high temperature heat storage medium first pipe. When the liquid level of the high-temperature heat storage medium low-level tank 220 is high, the high-temperature heat storage medium first valve component 241 is opened to prevent the liquid level of the high-temperature heat storage medium low-level tank 220 from being too high.

In this embodiment, the high temperature heat storage medium first valve assembly 241 includes: two valve groups connected in parallel; each valve set comprises three valves in series: two check valves and an inlet regulating valve disposed between the two check valves.

The high temperature heat storage medium second valve assembly 242 increases the heat storage medium level in the high temperature heat storage medium low level tank 220 by reducing the air pressure in the high temperature heat storage medium low level tank; the high-temperature heat storage medium low-level tank 220 is provided with a high-temperature heat storage medium first gas discharge pipeline 2412, and the high-temperature heat storage medium first gas discharge pipeline 2412 forms a high-temperature heat storage medium second pipeline; the high-temperature heat storage medium second valve assembly 242 is disposed on the high-temperature heat storage medium second pipe. When the liquid level of the high-temperature heat storage medium low-level tank 220 is low, the high-temperature heat storage medium second valve assembly 242 is opened, so that the liquid level of the high-temperature heat storage medium low-level tank 220 is prevented from being too low. In this embodiment, the outlet height of the first gas outlet pipe 2412 for high-temperature heat storage medium is as high as the highest liquid level of the high-temperature heat storage medium high-level tank 120.

It should be noted that if the uninterrupted compressed gas source 300 provides air, the outlet of the first gas discharge pipe can be directly connected to the atmosphere. If a gas other than the air supplied from the uninterruptible compressed gas source 300, such as nitrogen, is to be considered for recycling the relevant gas, the outlet of the first gas outlet pipe 2412 for high-temperature heat storage medium may be connected to a gas recycling device, and the recycled gas may be considered to be returned to the uninterruptible compressed gas source 300.

In this embodiment, the second valve assembly 242 includes two valve sets connected in parallel; each valve set comprises two valves in series: an exhaust regulating valve and a check valve.

When the first high-temperature heat storage medium line and the second high-temperature heat storage medium line share a part of the pipeline, the third high-temperature heat storage medium valve assembly 243 is disposed on the shared pipeline. In this embodiment, the third high temperature heat storage medium valve assembly 243 includes a check valve.

Wherein, the high temperature heat storage medium transmission subsystem still includes: a high-temperature heat storage medium low-level tank liquid level sensor 246, a high-temperature heat storage medium high-low level tank isolation valve 247, a high-temperature heat storage medium temperature regulator 248, a high-temperature heat storage medium heater 249, a high-temperature heat storage medium air pressure regulating valve 250, a high-temperature heat storage medium temperature sensor 251, a high-temperature heat storage medium fourth valve component 244 and a high-temperature heat storage medium flexible connector 245.

In this embodiment, the high temperature thermal storage medium temperature regulator 248 is an air cooler/heater. The high temperature heat storage medium heater 249 is an electric heater.

The high-temperature heat storage medium low-level tank liquid level sensor 246 is installed on the high-temperature heat storage medium low-level tank 220 and used for detecting the liquid level of the heat storage medium in the high-temperature heat storage medium low-level tank 220. When the high-temperature heat storage medium low-level tank liquid level sensor 246 sends a low liquid level alarm, the liquid level of the high-temperature heat storage medium low-level tank 220 is increased by opening the high-temperature heat storage medium second valve component 242 so as to be at a normal operation liquid level; when the high temperature heat storage medium low level tank level sensor 246 sends a high level alarm, the high temperature heat storage medium first valve component 241 is opened to lower the liquid level of the high temperature heat storage medium low level tank 220 to make it at the normal operation liquid level.

A high-temperature heat storage medium first pipeline is arranged between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220, the high-temperature heat storage medium high-level tank 120 is connected with the high-temperature heat storage medium low-level tank 220 through the high-temperature heat storage medium first pipeline, and a high-temperature heat storage medium third pipeline is formed by the high-temperature heat storage medium first pipeline between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium; and the high-temperature heat storage medium high-low tank isolation valve 247 is arranged on the high-temperature heat storage medium third pipeline. Once the high-temperature heat storage medium low-level tank 220 has a fault and needs to be shut down for maintenance, the flow of the heat storage medium between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220 is cut off by the high-temperature heat storage medium high-level tank isolation valve 247, and then the heat storage medium is frozen by introducing compressed air into the high-temperature heat storage medium temperature regulator 248, so that the flow of the heat storage medium between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220 is further completely cut off.

The uninterrupted compressed gas source 300 is connected with the inlet of the high-temperature heat storage medium temperature regulator 248 through a pipeline, and a fourth pipeline of the high-temperature heat storage medium is formed by the connecting pipeline between the uninterrupted compressed gas source 300 and the inlet of the high-temperature heat storage medium temperature regulator 248. The high-temperature heat storage medium heater 249 is located on the high-temperature heat storage medium fourth pipeline. The outlet of the high-temperature heat storage medium temperature regulator 248 is connected with a high-temperature heat storage medium second gas discharge pipe, and the high-temperature heat storage medium air pressure regulating valve 250 is arranged on the high-temperature heat storage medium second gas discharge pipe. The high temperature heat storage medium temperature sensor 251 is mounted on the high temperature heat storage medium temperature regulator 248.

The high temperature heat storage medium fourth valve assembly 244 is used to regulate the amount and flow rate of gas into the high temperature heat storage medium temperature regulator 248; the fourth valve assembly 244 is disposed on the fourth pipe and between the heater 249 and the uninterrupted compressed gas source 300. Meanwhile, the high temperature heat storage medium fourth valve component 244 is used for controlling the air pressure in the high temperature heat storage medium temperature regulator 248, which plays a role in regulating the cooling speed on one hand; on the other hand, when a leakage failure occurs in the heat storage medium side line of the high-temperature heat storage medium temperature regulator 248, the pressure on the gas side can be controlled to be higher than the pressure on the heat storage medium side, thereby preventing the heat storage medium from leaking outside.

In this embodiment, the fourth valve assembly 244 for storing high temperature heat medium includes: one regulating valve and one check valve.

The high-temperature heat storage medium flexible connector 245 is arranged on the high-temperature heat storage medium third pipeline and is positioned between the high-temperature heat storage medium low-level tank 220 and the high-temperature heat storage medium high-low-level tank isolation valve 247. The high-temperature heat storage medium flexible connector 245 can be a corrugated pipe, and has the function of realizing flexible connection between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220, and when the high-temperature heat storage medium high-level tank 120 expands with heat and contracts with cold due to temperature change, the thermal stress between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220 is reduced.

Wherein, the high temperature heat storage medium transmission subsystem still includes: a high temperature heat storage medium transfer pump outlet recirculation valve 131; wherein:

a second high-temperature heat storage medium pipeline is arranged between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220; one end of the high-temperature heat storage medium second pipeline is connected with the inlet of the high-temperature heat storage medium high-level tank 120, and the other end of the high-temperature heat storage medium second pipeline is connected with the outlet of the high-temperature heat storage medium delivery pump 420; the high-temperature heat storage medium second pipeline forms a high-temperature heat storage medium fifth pipeline, and heat storage medium can be pumped into the high-temperature heat storage medium high-level tank 120 from the high-temperature heat storage medium low-level tank 220 along the high-temperature heat storage medium fifth pipeline; and the high-temperature heat storage medium conveying pump outlet recirculation valve 131 is arranged on the fifth high-temperature heat storage medium pipeline.

The high-temperature heat storage medium delivery pump 420 is installed on the high-temperature heat storage medium low-level tank 220, and has a function of delivering out the molten salt in the high-temperature heat storage medium low-level tank 220, on one hand, returning to the high-temperature heat storage medium high-level tank 120 through a fifth high-temperature heat storage medium pipeline, and on the other hand, delivering the molten salt to the heat storage medium heat exchange subsystem 600 through a pipeline. Because the height and volume of the high-temperature heat storage medium low-level tank 220 are very small compared with the high-temperature heat storage medium high-level tank 120, the equipment cost can be reduced and the system reliability can be improved compared with the use of a long-shaft submerged molten salt pump, and because the installation height of the high-temperature heat storage medium low-level tank 220 is lower than that of the high-temperature heat storage medium high-level tank 120, the amount of molten salt which cannot be utilized due to the use of the long-shaft submerged molten salt pump in the high-temperature heat storage medium high-level tank 120 can be reduced.

When the high-temperature heat storage medium low-level tank 220 needs to cut off the flow of the molten salt between the high-temperature heat storage medium high-level tank 120, the high-temperature heat storage medium high-level tank isolation valve 247 is closed to cut off the rapid flow of the molten salt, and then the compressed gas is sent into the high-temperature heat storage medium temperature regulator 248 from the uninterrupted compressed gas source 300 through the gas source pipeline. In the process, the high-temperature heat storage medium heater 249 does not work, the high-temperature heat storage medium fourth valve assembly 244 adjusts the amount and flow rate of gas entering the high-temperature heat storage medium temperature adjuster 248, the molten salt in a section of connecting pipeline between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220 is cooled through convection heat transfer, the molten salt in the section of pipeline is completely solidified and does not flow, the temperature of the cooled part of the molten salt pipeline is adjusted through the high-temperature heat storage medium air pressure adjusting valve 250, the opening degree of the high-temperature heat storage medium air pressure adjusting valve 250 is related to the temperature of the high-temperature heat storage medium temperature sensor 251 installed on the cooled part of the molten salt pipeline, the temperature of the high-temperature heat storage medium temperature.

When molten salt flow needs to be restarted between the high-temperature heat storage medium low-level tank 220 and the high-temperature heat storage medium high-level tank 210, the high-temperature heat storage medium high-level tank isolation valve 247 is opened, then compressed gas is sent into the high-temperature heat storage medium temperature regulator 248 from the uninterrupted compressed gas source 300 through the gas source pipeline, and the high-temperature heat storage medium fourth valve assembly 244 regulates the amount and flow rate of gas entering the high-temperature heat storage medium temperature regulator 248. In the process, the high-temperature heat storage medium heater 249 starts to operate, and heats the gas fed into the high-temperature heat storage medium temperature regulator 248. The heated gas enters the high-temperature heat storage medium temperature regulator 248, and the molten salt in a section of connecting pipeline between the high-temperature heat storage medium high-level tank 120 and the high-temperature heat storage medium low-level tank 220 is heated through convection heat transfer, so that the molten salt in the section of pipeline is melted and flows.

The low temperature heat storage medium transfer subsystem further comprises an uninterrupted compressed gas source 300, which shares the uninterrupted compressed gas source 300 with the high temperature heat storage medium transfer subsystem. In this embodiment, the low-temperature heat storage medium is low-temperature molten salt, the low-temperature heat storage medium delivery pump 410 is a molten salt pump, and the uninterrupted compressed gas source 300 is a buffer gas storage tank. The gas in the buffer gas storage tank can be air or gas other than air, such as nitrogen and the like. The present invention is not limited to specific gas species.

The uninterrupted compressed gas source 300 is communicated with the gas phase space of the low-temperature heat storage medium low-level tank 210 through a gas source pipeline, and the gas source pipeline forms a first low-temperature heat storage medium pipeline; the uninterrupted compressed gas source 300 increases the gas pressure in the low-temperature heat storage medium low-level tank 210 by charging gas into the low-temperature heat storage medium low-level tank 210, thereby reducing the liquid level of the heat storage medium in the low-temperature heat storage medium low-level tank 210.

Wherein, the low temperature heat-storage medium transmission subsystem still includes: a first valve 341, a second valve 342, and a third valve 343.

The low-temperature heat storage medium first valve component 341 is configured to adjust the charge amount of the uninterrupted compressed gas source provided to the low-temperature heat storage medium low-level tank 210; the low temperature heat storage medium first valve assembly 341 is disposed on the low temperature heat storage medium first pipe. When the liquid level of the low-temperature heat storage medium low-level tank 210 is high, the first valve component 341 of the low-temperature heat storage medium is opened to prevent the liquid level of the low-temperature heat storage medium low-level tank 210 from being too high.

In this embodiment, the low temperature heat storage medium first valve assembly 341 includes: two valve groups connected in parallel; each valve set comprises three valves in series: two check valves and an inlet regulating valve disposed between the two check valves.

The low-temperature heat storage medium second valve assembly 342 increases the heat storage medium liquid level in the low-temperature heat storage medium low-level tank 210 by reducing the gas pressure in the low-temperature heat storage medium low-level tank 210; the low-temperature heat storage medium low-level tank 210 is provided with a low-temperature heat storage medium first gas discharge pipe 3412, and the low-temperature heat storage medium first gas discharge pipe 3412 forms a low-temperature heat storage medium second pipe; the low-temperature heat storage medium second valve component 342 is disposed on the low-temperature heat storage medium second pipeline. When the liquid level of the low-temperature heat storage medium low-level tank 210 is low, the low-temperature heat storage medium second valve component 342 is opened, so that the liquid level of the low-temperature heat storage medium low-level tank 210 is prevented from being too low. In this embodiment, the outlet height of the low-temperature heat storage medium first gas discharge pipe 3412 is the same as the highest liquid level of the low-temperature heat storage medium high-level tank 110.

It should be noted that if the uninterrupted compressed gas source 300 provides air, the outlet of the first gas discharge pipe can be directly connected to the atmosphere. If the uninterrupted compressed gas source 300 provides a gas other than air, such as nitrogen, in consideration of the problem of recovering the relevant gas, the outlet of the first gas discharge conduit 3412 of the low-temperature heat storage medium may be connected to a gas recovery device, and the gas recovered by the device may be considered to be returned to the uninterrupted compressed gas source 300.

In this embodiment, the low-temperature heat storage medium second valve component 342 includes two valve groups connected in parallel; each valve set comprises two valves in series: an exhaust regulating valve and a check valve.

When the first low-temperature heat storage medium pipeline and the second low-temperature heat storage medium pipeline share part of the pipeline, the third low-temperature heat storage medium valve assembly 343 is disposed on the shared pipeline. In this embodiment, the third valve assembly 343 for low temperature heat storage medium comprises a check valve.

Wherein, the low temperature heat-storage medium transmission subsystem still includes: the system comprises a low-temperature heat storage medium low-level tank liquid level sensor 346, a low-temperature heat storage medium high-low level tank isolation valve 347, a low-temperature heat storage medium temperature regulator 348, a low-temperature heat storage medium heater 349, a low-temperature heat storage medium air pressure regulating valve 350, a low-temperature heat storage medium temperature sensor 351, a low-temperature heat storage medium fourth valve component 344 and a low-temperature heat storage medium flexible connector 345.

In this embodiment, the low temperature heat storage medium temperature regulator 348 is an air cooling/heating device. The low temperature heat storage medium heater 349 is an electric heater.

The low-temperature heat storage medium low-level tank liquid level sensor 346 is installed on the low-temperature heat storage medium low-level tank 210, and is used for detecting the liquid level of the heat storage medium in the low-temperature heat storage medium low-level tank 210. When the low-temperature heat storage medium low-level tank liquid level sensor 346 sends a low liquid level alarm, the liquid level of the low-temperature heat storage medium low-level tank 210 is increased by opening the low-temperature heat storage medium second valve assembly 342 to be at a normal operation liquid level; when the low temperature heat storage medium low level tank level sensor 346 sends a high level alarm, the low temperature heat storage medium first valve assembly 341 is opened to lower the liquid level of the low temperature heat storage medium low level tank 210 to be at the normal operating liquid level.

A low-temperature heat storage medium first pipeline is arranged between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210, the low-temperature heat storage medium high-level tank 110 is connected with the low-temperature heat storage medium low-level tank 210 through the low-temperature heat storage medium first pipeline, and a low-temperature heat storage medium third pipeline is formed by the low-temperature heat storage medium first pipeline between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium; and the low-temperature heat storage medium high-low tank isolation valve 347 is arranged on the low-temperature heat storage medium third pipeline. Once the low-temperature heat storage medium low-level tank 210 has a fault and needs to be shut down for maintenance, the flow of the heat storage medium between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210 is cut off by the low-temperature heat storage medium high-level tank isolation valve 347, and then the heat storage medium is frozen by introducing compressed air into the low-temperature heat storage medium temperature regulator 348, so that the flow of the heat storage medium between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210 is further completely cut off.

The uninterrupted compressed gas source 300 is connected with the inlet of the low-temperature heat storage medium temperature regulator 348 through a pipeline, and a fourth pipeline of the low-temperature heat storage medium is formed by the connecting pipeline between the uninterrupted compressed gas source 300 and the low-temperature heat storage medium temperature regulator 348. The low-temperature heat storage medium heater 349 is located on the low-temperature heat storage medium fourth pipeline. An outlet of the low-temperature heat storage medium temperature regulator 348 is connected with a low-temperature heat storage medium second gas discharge pipe, and the low-temperature heat storage medium pressure regulating valve 350 is arranged on the low-temperature heat storage medium second gas discharge pipe. The low temperature heat storage medium temperature sensor 351 is mounted on the low temperature heat storage medium temperature regulator 348.

The fourth valve component 344 is used to adjust the amount and flow rate of gas into the low temperature storage medium temperature regulator 348; the low temperature heat storage medium fourth valve component 344 is disposed on the low temperature heat storage medium fourth pipe and is located between the low temperature heat storage medium heater 349 and the uninterrupted compressed gas source 300. Meanwhile, the low-temperature heat storage medium fourth valve component 344 is used for controlling the air pressure in the low-temperature heat storage medium temperature regulator 348, so that the function of regulating the cooling speed is achieved; on the other hand, when a leakage failure occurs in the heat storage medium side pipe in the low-temperature heat storage medium temperature regulator 348, the pressure on the gas side can be controlled to be higher than the pressure on the heat storage medium side, thereby preventing the heat storage medium from leaking outside.

In this embodiment, the fourth valve component 344 for low temperature heat storage medium includes: one regulating valve and one check valve.

The low-temperature heat storage medium flexible connector 345 is arranged on the low-temperature heat storage medium third pipeline and is positioned between the low-temperature heat storage medium low-level tank 210 and the low-temperature heat storage medium high-level and low-level tank isolation valve 347. The low-temperature heat storage medium flexible connector 345 may be a corrugated pipe, and has a function of realizing flexible connection between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210, and when the low-temperature heat storage medium high-level tank 110 expands with heat and contracts with cold due to temperature change, thermal stress between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210 is reduced.

Wherein, the low temperature heat-storage medium transmission subsystem still includes: a low temperature heat storage medium transfer pump outlet recirculation valve 130; wherein:

a second low-temperature heat storage medium pipeline is arranged between the high-temperature heat storage medium tank 110 and the low-temperature heat storage medium low-level tank 210; one end of the low-temperature heat storage medium second pipeline is connected with the inlet of the low-temperature heat storage medium high-level tank 110, and the other end of the low-temperature heat storage medium second pipeline is connected with the outlet of the low-temperature heat storage medium delivery pump 410; the low-temperature heat storage medium second pipeline forms a fifth low-temperature heat storage medium pipeline, and heat storage medium can be pumped into the low-temperature heat storage medium high-level tank 110 from the low-temperature heat storage medium low-level tank 210 along the fifth low-temperature heat storage medium pipeline; the low-temperature heat storage medium delivery pump outlet recirculation valve 130 is arranged on the fifth low-temperature heat storage medium pipeline.

The low-temperature heat storage medium delivery pump 410 is installed on the low-temperature heat storage medium low-level tank 210, and has a function of delivering out the molten salt in the low-temperature heat storage medium low-level tank 210, on one hand, returning to the low-temperature heat storage medium high-level tank 110 through a fifth low-temperature heat storage medium pipeline, and on the other hand, delivering the molten salt to the heat storage medium heat absorption subsystem 500 through a pipeline. Because the height and volume of the low-temperature heat storage medium low-level tank 210 are very small compared to the low-temperature heat storage medium high-level tank 110, the equipment cost can be reduced and the system reliability can be improved compared to the use of a long-axis submerged molten salt pump, and because the installation height of the low-temperature heat storage medium low-level tank 210 is lower than that of the low-temperature heat storage medium high-level tank 110, the amount of molten salt which cannot be utilized due to the use of the long-axis submerged molten salt pump in the low-temperature heat storage medium high-level tank 110 can be reduced.

When the low-temperature heat storage medium low-level tank 210 needs to cut off the flow of the molten salt between the low-temperature heat storage medium high-level tank 110, the low-temperature heat storage medium high-level tank isolation valve 347 is closed to cut off the rapid flow of the molten salt, and then the continuous compressed gas source 300 sends compressed gas into the low-temperature heat storage medium temperature regulator 348 through the gas source pipeline. In the process, the low-temperature heat storage medium heater 349 does not work, the low-temperature heat storage medium fourth valve component 344 adjusts the amount and flow rate of gas entering the low-temperature heat storage medium temperature adjuster 348, a section of fused salt of a connecting pipeline between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210 is cooled through convection heat transfer, the fused salt of the section of pipeline is completely solidified and does not flow, the temperature of a cooled part of fused salt pipeline is adjusted through the low-temperature heat storage medium air pressure adjusting valve 350, the opening degree of the low-temperature heat storage medium air pressure adjusting valve 350 is related to the temperature of the low-temperature heat storage medium temperature sensor 351 mounted on the cooled part of fused salt pipeline, the temperature of the low-temperature heat storage medium temperature sensor 351 is controlled.

When molten salt flow needs to be restarted between the low-temperature heat storage medium low-level tank 210 and the low-temperature heat storage medium high-level tank 110, the low-temperature heat storage medium high-level tank isolation valve 347 is opened, then compressed gas is sent into the low-temperature heat storage medium temperature regulator 348 from the uninterrupted compressed gas source 300 through the gas source pipeline, and the amount and the flow rate of the gas entering the low-temperature heat storage medium temperature regulator 348 are regulated by the low-temperature heat storage medium fourth valve assembly 344. And in this process, the low temperature heat storage medium heater 349 starts operating to heat the gas fed into the low temperature heat storage medium temperature regulator 348. The heated gas enters the low-temperature heat storage medium temperature regulator 348, and the molten salt in a section of connecting pipeline between the low-temperature heat storage medium high-level tank 110 and the low-temperature heat storage medium low-level tank 210 is heated through convection heat transfer, so that the molten salt in the section of pipeline is melted and flows.

The heat storage medium heat exchange subsystem 600 comprises a heat exchanger 601 which is respectively connected with the low-temperature heat storage medium high-level tank 110 and the high-temperature heat storage medium transmission subsystem through pipelines, and valves are arranged on the connecting pipelines at two ends of the heat exchanger.

The heat storage medium heat absorption subsystem 500 comprises a heat absorber 502, a heat absorber inlet buffer tank 501 and a heat absorber outlet buffer tank 503; the heat absorber 502 is connected to a heat absorber inlet buffer tank 501 and a heat absorber outlet buffer tank 503, respectively; the heat absorber inlet buffer tank 501 is connected with the low-temperature heat storage medium transmission subsystem, and a valve is arranged on a connecting pipeline of the heat absorber inlet buffer tank and the low-temperature heat storage medium transmission subsystem; the heat absorber outlet buffer tank 503 is connected with the high-temperature heat storage medium high-level tank 120, and a valve is arranged on a connecting pipeline of the heat absorber outlet buffer tank and the high-temperature heat storage medium high-level tank.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.