WO2022267151A1

WO2022267151A1 - Solar photothermal power station salt melting system based on natural gas heat transfer oil furnace

Info

Publication number: WO2022267151A1
Application number: PCT/CN2021/108061
Authority: WO
Inventors: 栾海峰; 朱胜国; 杨志丹; 宗弟元; 李姗
Original assignee: 中国船舶重工集团新能源有限责任公司
Priority date: 2021-06-23
Filing date: 2021-07-23
Publication date: 2022-12-29
Also published as: CN113310214A; ES2960657A1

Abstract

A solar photothermal power station salt melting system based on a natural gas heat transfer oil furnace, relating to the technical field of photothermal salt melting and production. The present invention is intended to shorten the salt melting cycle and reduce the salt melting cost. The present invention comprises a salt melting furnace, a heat exchanger, and a molten salt storage tank; the salt melting furnace is communicated with a low-temperature molten salt inlet of the heat exchanger by means of a molten salt pipeline; the salt melting furnace is communicated with the molten salt storage tank by means of a conveying pump; a high-temperature molten salt outlet of the heat exchanger is communicated with the salt melting furnace; a connection relationship is established between the heat exchanger and a natural gas heat transfer oil furnace; the natural gas heat transfer oil furnace is used for providing a heat exchange heat source for the heat exchanger; the heat exchanger may be an oil-salt heat exchanger, or may be replaced by an electric heater, or may be a heat collection system for photothermally heating molten salt, directly. According to the present invention, salt is molten photothermally, the salt melting speed is significantly increased, and the system is simple in structure, simple and convenient in operation, high in safety, energy-saving and environment-friendly, and clean and efficient.

Description

A salt-forming system of solar thermal power station based on natural gas heat conduction oil furnace

technical field

The invention relates to a salt chemical system of a solar photothermal power station based on a natural gas heat-conducting oil furnace, and belongs to the technical field of salt chemical systems.

Background technique

Before the molten salt is put into the solar thermal power station, it is mainly supplied in solid form (because molten salt is solid at room temperature), and the supply in solid form is convenient for the transportation and storage of molten salt. And when the molten salt needs to be put into the solar thermal power station for heat storage, it is necessary to convert a large amount of solid molten salt into high temperature liquid molten salt. A key procedure before the system enters commissioning and operation. The molten salt changes from solid to liquid through this process. The high-temperature molten salt enters the system and starts to circulate, and remains liquid throughout the life of the power station.

In the existing photothermal solar photothermal power station, there are roughly two schemes to realize the salt transformation. One is to use the electric heater to initialize the salt, and then use the molten salt circulation pump to pump the low-temperature liquid molten salt into the natural gas salt furnace In the process, the molten salt in the coil in the molten salt furnace is heated to a high temperature state by the high-temperature flue gas generated by burning natural gas, and then transported back to the molten salt tank. Sodium nitrate and potassium nitrate (solid molten salt) are added to the molten salt tank in proportion. When the temperature of the molten salt in the molten salt tank meets the requirements, the molten salt is transported to the molten salt tank through another molten salt delivery pump; The second is that sodium nitrate and potassium nitrate are pulverized and mixed in proportion, and then directly enter the natural gasification salt furnace. A heat exchange coil is installed in the furnace, and the pipe contains high-temperature flue gas. Its flow direction is opposite to that of the liquid in the furnace. The molten salt overflows into the buffer tank through the overflow pipe, and then pumps from the buffer tank into the molten salt tank. Both of the above two traditional salt melting methods use the flue gas after natural gas combustion as the heat source for heating solid molten salt particles, and a large amount of natural gas is consumed in the salt melting process. Due to the technical limitations of the natural gas furnace itself and for safety reasons, the salt melting speed is about 30-40 t/h. After the desalination is completed, the supporting desalination equipment has no use value in this project and can only be used for the next project to desalt again or put aside for waste.

In addition to the above statements, the conventional way of salting also has the following disadvantages:

1. The cost of the built-up salt melting furnace system using natural gas heating to realize salt melting is high, and after the salt melting is realized once, the molten salt is put into the solar thermal system for use, and there is no need to melt salt again, so The supporting natural gas salt furnace system equipment cannot be used reasonably;

2. When using the natural gas salt furnace system to realize salt conversion, natural gas needs to be burned. In the molten salt project of a large-scale solar thermal power station with tens of thousands of tons, the cost of natural gas consumed is relatively high;

3. The use of natural gas salt furnace system to burn natural gas emits a large amount of carbon dioxide, which has certain pollution to the environment;

4. The heating capacity of the natural gas salt furnace system is limited. In the molten salt project of a large-scale solar thermal power station with tens of thousands of tons, the salt melting speed is relatively slow and the salt melting cycle is long.

Based on the above situation, it is of great significance to carry out the research on the technical solution of salt to shorten the cycle of salt, to reduce the cost of salt, to improve the speed and quality of salt, and to ensure the balance between solar thermal power generation and salt.

technical problem

The present invention aims at shortening the period of desalting and reducing the cost of desalting. A brief overview of the invention is given below in order to provide a basic understanding of some aspects of the invention. It should be understood that this summary is not an exhaustive overview of the invention. It is not intended to identify key or critical parts of the invention nor to delineate the scope of the invention.

technical solution

A salt chemical system of solar photothermal power station based on a natural gas heat transfer oil furnace, including a salt furnace, a heat exchanger, a molten salt storage tank and a natural gas heat transfer oil furnace, the heat exchanger has a molten salt inlet, a molten salt outlet, a heat source The outlet and the heat source inlet, the salt furnace is connected to the molten salt inlet of the heat exchanger through the molten salt pipeline, the salt furnace is connected to the molten salt storage tank through the delivery pump, and the molten salt outlet of the heat exchanger is connected to the salt tank through the first pipeline. The furnace is connected, and the heat source outlet and heat source inlet of the heat exchanger are connected to the natural gas heat transfer oil furnace, and the natural gas heat transfer oil furnace is used to provide heat exchange heat source for the heat exchanger.

Preferably: an auxiliary electric heater is also included, the inlet of the auxiliary electric heater communicates with the molten salt pipeline, and the outlet of the auxiliary electric heater communicates with the salt furnace through the second pipeline.

Preferably: valves and temperature measuring instruments are respectively installed on the first pipeline and the second pipeline.

Preferably: the electric energy used in the auxiliary electric heater comes from abandoned wind power, abandoned photovoltaic power or low valley power.

Preferably: there are multiple heat exchangers, and multiple heat exchangers are installed in parallel.

Preferably: there are multiple heat exchangers, and multiple heat exchangers are installed in series.

Preferably: two adjacent heat exchangers are connected through secondary molten salt pipelines.

Preferably: valves and temperature measuring instruments are installed on the secondary molten salt pipeline.

Preferably: the heat exchanger is a shell-and-tube heat exchanger, a tube-and-tube heat exchanger or a plate heat exchanger.

The present invention has the following beneficial effects:

1. The salt melting system of the present invention solves the problem that the solid molten salt of conventional photothermal power plants is melted through the special natural gas salt melting furnace system, while the conventional special natural gas salt melting furnace realizes the salt melting process. The consumption and other factors are limited, the salt conversion efficiency is not high, the entire salt conversion cycle cannot be guaranteed, and the cost of salt conversion fuel is high.

2. The present invention utilizes the photothermal power generation system to carry out the salt conversion work, so that both power generation and salt conversion are correct, and the salt conversion capacity is much greater than that of the dedicated natural gas salt conversion furnace system;

3. In the present invention, when there is sun in the daytime, salt is converted by light and heat, and when there is no sun at night, electric heating is used to absorb abandoned electricity or low-peak electricity to convert salt, which effectively shortens the cycle of salt conversion.

4. Compared with the conventional way of salt melting, the present invention realizes salt melting through photothermal method, and its speed of salt melting is significantly improved, and the system is simple, easy to operate, high in safety, energy-saving and environment-friendly.

5. Using the salt solution solution of the present invention, the sodium nitrate and potassium nitrate are crushed and transported to the salt furnace in proportion. After initializing the salt with an electric heater, the molten salt circulating pump is used to melt the low-temperature liquid in the salt furnace. The salt is pumped into the oil-salt heat exchanger, and the molten salt in the oil-salt heat exchanger is heated to a high temperature through a natural gas heat-conducting oil furnace, and then transported back to the salt furnace. The high-temperature liquid salt is mixed with solid molten salt to form a low temperature above 270°C Liquid molten salt is transported and stored in molten salt storage tanks.

The invention saves the construction cost by utilizing the original heat exchange equipment of the photothermal power station. After the salt is completed, the supporting feeding system can be disassembled and recycled for reuse, and the salt furnace and electric heater can be directly converted into a high-temperature energy storage system, which is used to absorb abandoned wind and light, and realize energy storage.

6. Using the salt melting system of the present invention, its salt melting speed exceeds 210 tons per hour, which is five times faster than the traditional salt melting speed, and can exceed 4,000 tons per day, which is more than four times the previous single-day salt melting world record. It only takes two and a half weeks to melt 70,000 tons of salt, which is two months faster than the traditional way of salt melting, saving tens of millions of yuan in fossil fuels for salt melting, and saving 20% in equipment investment compared with traditional salt melting systems. According to calculations, the realization of energy storage power generation two months in advance can create 60 million kWh of power generation revenue.

Description of drawings

Figure 1 is a schematic diagram of a salt chemical system based on a natural gas heat conduction oil furnace;

Fig. 2 is the composition diagram of the chemical salt system in the second specific embodiment;

Fig. 3 is the configuration diagram of the salt-dissolving system of the heat exchanger in the second specific embodiment;

Fig. 4 is a schematic diagram of the relationship between the amount of salt and the period of salt in the traditional way of salt and the way of salt in the present invention;

In the figure, 1- salt furnace, 2- heat exchanger, 3- molten salt storage tank, 4- molten salt pipeline, 5- delivery pump, 6- natural gas heat transfer oil furnace, 7- secondary molten salt pipeline, 8- Valve, 9-temperature measuring instrument, 10-auxiliary electric heater, 11-first pipeline, 12-second pipeline, 21-molten salt inlet, 22-molten salt outlet, 23-heat source outlet, 24-heat source inlet, 14 - circulation pump.

Embodiments of the present invention

In order to make the object, technical solution and advantages of the present invention clearer, the present invention is described below through specific embodiments shown in the accompanying drawings. It should be understood, however, that these descriptions are exemplary only and are not intended to limit the scope of the present invention. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concept of the present invention.

Specific implementation mode one:

Referring to Fig. 1 , this embodiment provides a salt-forming system for a solar thermal power station based on a natural gas heat-conducting oil furnace, which includes a salt-forming furnace 1, a heat exchanger 2, a molten salt storage tank 3 and a natural gas heat-conducting oil furnace 6. The heat exchanger 2 has a molten salt inlet 21, a molten salt outlet 22, a heat source outlet 23, and a heat source inlet 24. The salt furnace 1 is connected to the molten salt inlet 21 of the heat exchanger 2 through a molten salt pipeline 4, and the salt furnace 1 The delivery pump 5 communicates with the molten salt storage tank 3, the molten salt outlet 22 of the heat exchanger 2 communicates with the salt furnace 1 through the first pipeline 11, and the heat source outlet 23 and the heat source inlet 24 of the heat exchanger 2 conduct heat with natural gas The oil furnace 6 establishes a connection relationship, and the natural gas heat-conducting oil furnace 6 is used to provide heat exchange heat source for the heat exchanger 2 .

Wherein, in the chemical salt furnace 1, after the solid salt and the high-temperature molten salt are mixed in the chemical salt furnace 1, a medium-temperature liquid molten salt is formed, and a part of the medium-temperature liquid molten salt is sent to the molten salt storage tank 3 through the delivery pump 5 for storage. The other part is driven into the heat exchanger 2 through the circulation pump, and the medium-temperature molten salt is heated to the high-temperature molten salt by the heat exchanger 2, and then the high-temperature molten salt is transported to the salt furnace 1 through the circulation pump, and is used again for the salt work, thus forming a cycle of salt work;

In this embodiment, the heat exchanger 2 is a heat-conducting oil heat exchanger. When the system is working in the salt process, solid salt and 300-400 degree high temperature molten salt are mixed in the salt furnace 1 to form a 280-340 degree medium temperature Liquid molten salt, the formed medium-temperature liquid molten salt is sent to the molten salt storage tank 3 through the delivery pump 5 for storage, and the other part is pumped into the heat exchanger 2 from the molten salt inlet 21 through the circulation pump. At the same time, the natural gas heat transfer oil The furnace 6 communicates with the heat source outlet 23 and the heat source inlet 24 of the heat exchanger 2, and transports the high-temperature heat-conducting oil absorbed in the natural gas heat-conducting oil furnace 6 to the heat exchanger 2. Inside the heat exchanger 2, high-temperature heat-conducting oil is used Exchange heat to the medium-temperature molten salt entering the heat exchanger 2, so that the temperature of the medium-temperature molten salt (280-340°C) reaches the high-temperature molten salt (300-400°C), and then pass the high-temperature molten salt through the first pipeline 11 Transport to the salt furnace 1 to complete the salt conversion work again. The amount of transport ensures that the solid molten salt newly added to the salt furnace 1 can reach a certain temperature and melt the solid molten salt. Repeat the above steps to realize the cycle salt work.

The salt melting system in this embodiment solves the problem that the solid molten salt of conventional photothermal power plants is converted into salt through the natural gas salt furnace system, while the conventional natural gas salt furnace realizes the salt conversion process, the heating capacity of the furnace, the amount of natural gas and other factors Due to the limitation, the whole cycle of salt melting is long, and the construction and operation costs of salt melting are relatively high.

Using the salt melting system of this embodiment, the system utilizes the power generation and heat storage system of the photothermal power station to carry out the salt melting work, so that both power generation and salt melting are correct, and the salt melting capacity is much greater than that of the traditional natural gas salt melting furnace system;

Inside the heat exchanger 2, high-temperature heat-conducting oil is used to exchange heat to the medium-temperature molten salt entering the heat exchanger 2, so that the temperature of the medium-temperature molten salt reaches the high-temperature molten salt, wherein the heat-conducting oil comes from the natural gas heat-conducting oil furnace 6. Wherein the heat transfer oil in the heat exchanger 2 comes from a natural gas heat transfer oil furnace.

In this embodiment, the salt furnace 1 is used to convert the pulverized solid molten salt into liquid molten salt, and the salt furnace 1 is a container for realizing the salt; the heat exchanger 2 is a shell-and-tube heat exchanger , shell and tube heat exchanger or plate heat exchanger.

Specific implementation mode two:

Referring to Fig. 1 and Fig. 2, on the basis of the specific embodiment one, an auxiliary electric heater 10 is also included, the inlet of the auxiliary electric heater 10 communicates with the molten salt pipeline 4, and the outlet of the auxiliary electric heater 10 passes through the second pipeline 12 Connected with the salt furnace 1;

Specifically: a part of the medium-temperature molten salt in the chemical salt furnace 1 flows into the heat exchanger 2 and/or the auxiliary electric heater 10, and the medium-temperature molten salt is heated to high temperature melting by the heat exchanger 2 and/or the auxiliary electric heater 10 salt, and then the high-temperature molten salt is transported to the salt furnace 1 through the circulation pump 14 to realize the circulation of salt;

When the system is working on melting salt, solid salt and 300-400 degree high temperature molten salt are mixed in the salt furnace 1 to form 280-340 degree medium temperature liquid molten salt, and the formed medium temperature liquid molten salt is sent through the delivery pump 5 all the way The molten salt storage tank 3 is stored, and the other part is pumped into the heat exchanger 2 or the auxiliary electric heater 10 through the circulation pump 14, and the medium-temperature liquid molten salt (280-340°C) is passed through the heat exchanger 2 or the auxiliary electric heater 10 Heating and transforming into high-temperature liquid molten salt (300-400°C), and then transporting the high-temperature molten salt to the salt furnace 1 to realize the circulation of salt, the amount of delivery ensures that the solid molten salt newly added to the salt furnace 1 can Reach a certain temperature and melt the solid molten salt.

The number of auxiliary electric heaters 10 is multiple, and multiple auxiliary electric heaters 10 are arranged in the whole chemical salt system in parallel or in series;

In this embodiment, using the salt chemical system of this embodiment, the salt chemical speed exceeds 210 tons per hour, which is five times faster than the traditional salt chemical process, and can exceed 4,000 tons per day, which is four times the previous single-day salt chemical world record As mentioned above, if it only takes two and a half weeks to melt 70,000 tons of salt continuously, which is two months faster than the traditional salt melting method, it can realize heat storage island power generation in advance and save tens of millions of fossil fuels for salt melting, and the investment in equipment is also higher than that of traditional salt melting systems Save 20%, the specific comparison is shown in the figure:

Table 1. Comparison of photothermal salt system and traditional salt system

It should be noted that in solar power generation projects, the current international conventional salt system uses natural gas salt furnace, which uses the flue gas after natural gas combustion to provide heat to melt solid molten salt into a liquid state.

When a solar power generation project needs to melt salt, the conventional way is to buy a molten salt furnace, and then use the flue gas after natural gas combustion to provide heat to melt the solid molten salt into a liquid state;

Different from the conventional way of salt conversion, in this embodiment, the original equipment of the solar power plant is used for the salt conversion operation. For some equipment, the original function of this equipment is to generate electricity from solar energy. In this embodiment, according to the coordination and connection methods of the various technical features in this embodiment, a salt chemical system is formed, and the system is used to realize chemical Salt, which saves the cost of purchasing and building natural gas salt furnaces, reduces carbon dioxide emissions in the salt process, and improves the speed and cycle of salt conversion by using existing equipment (as shown in Figure 4) ;

It should be noted that the heat storage medium used in the solar-thermal power station project is high-temperature molten salt. Taking the 100 MW trough-type heat-conducting oil solar-thermal power generation project in Wulate Zhongqi as an example, the power station is equipped with a high-temperature molten salt heat storage system. The high-temperature molten salt used in the system is a mixture of 40% potassium nitrate and 60% sodium nitrate by mass fraction. Before the molten salt energy storage system is put into operation, the solid molten salt must be melted and injected into the cold salt tank. This step (saltification) plays a vital role in the smooth commissioning and official commissioning of the heat storage system. At present, the conventional salt melting systems in the world all use natural gas salt melting furnaces, which use the flue gas after natural gas combustion to provide heat to melt the solid molten salt into a liquid state. This conventional salt conversion system not only has a low rate of salt conversion and cannot put the heat storage system into normal operation in a short period of time, but also consumes a large amount of fossil fuels, which is contrary to the "double carbon" commitment. However, limited by the high melting temperature of molten salt and many technical difficulties in the salt melting system, practical exploration of high-speed, low-carbon new salt melting technology at home and abroad is almost zero.

The use of the salt chemical system of this embodiment can ensure both solar thermal power generation and salt chemical conversion, and it is of great significance to realize salt chemical conversion in a solar thermal power generation project.

Specific implementation mode three:

With reference to Fig. 1, shown in Fig. 2, and on the basis of specific embodiment one and specific embodiment two, valve 8 and temperature measuring instrument 9 are respectively installed on described first pipeline 11 and second pipeline 12, valve 8 uses To control the switch of the pipeline, the temperature measuring instrument 8 is used to measure the temperature of the fluid in the pipeline. The opening and closing of the molten salt in the first pipeline 11 and the second pipeline 12 is monitored in real time by using the information interaction between the valve 8 and the temperature measuring instrument 9, so as to ensure the smooth progress of the salt melting work.

Specific implementation mode four:

On the basis of Embodiment 2, the electric energy used in the auxiliary electric heater 10 comes from low-cost electricity such as abandoned wind power, abandoned photovoltaic power, and low-peak electricity. The cost of this electric energy is lower than the cost of electric energy provided by conventional power stations.

Specific implementation mode five:

Referring to Fig. 3, this embodiment provides a solar thermal power station salt system based on a natural gas heat conduction oil furnace. The difference from Embodiment 1 is that the number of heat exchangers 2 is multiple, and multiple heat exchangers 2 is installed in parallel. Multiple heat exchangers 2 arranged in parallel can realize simultaneous heating of medium-temperature liquid molten salt at 280-340 degrees to reach high-temperature molten salt at 300-400 degrees. In addition, the work/work of any one of the heat exchangers 2 can also be individually controlled. It is closed without affecting the work of other heat exchangers 2. In the whole system, the method of connecting multiple heat exchangers 2 in parallel is flexible and easy to use. When an accident occurs in a single heat exchanger 2, it will not affect the operation of the entire salt chemical system The advantages.

Specific implementation method six:

Referring to Fig. 3, this embodiment provides a solar thermal power station salt system based on a natural gas heat-conducting oil furnace. The difference from Embodiment 1 is that there are multiple heat exchangers 2, and multiple heat exchangers 2 The heater 2 is installed in series. Using series heat exchanger 2, medium temperature liquid molten salt at 280-340 degrees can flow through one channel and undergo multiple heat exchanges to achieve high temperature molten salt at 300-400 degrees, and the whole system has only one channel in series, which is convenient for switching control the entire system.

Specific implementation mode seven:

Referring to FIG. 3 , on the basis of Embodiment 5, two adjacent heat exchangers 2 are communicated through a secondary molten salt pipeline 7 . A valve 8 for opening/closing the secondary molten salt pipeline 7 and a temperature measuring instrument 8 for measuring the temperature of liquid molten salt circulating in the secondary molten salt pipeline 7 are installed on the secondary molten salt pipeline 7 . With such arrangement, the 280-340°C medium-temperature liquid molten salt flowing out of the salt furnace 1 enters the heat exchanger 2, and in the heat exchanger 2, the 280-340°C medium-temperature liquid molten salt is raised to a 300-400°C high-temperature molten salt; If the medium-temperature liquid molten salt in the heat exchanger 2 cannot effectively exchange heat to the high-temperature molten salt temperature state, the secondary molten salt pipeline 7 is opened to transport the liquid molten salt to another parallel heat exchanger 2 again , and further heat-exchange the liquid molten salt until it reaches a high temperature molten salt state of 300-400 degrees.

Specific implementation mode nine:

Referring to Fig. 1 and Fig. 3, on the basis of the fifth specific embodiment, the heat exchanger 2 is used to heat and convert medium-temperature liquid molten salt (280-340°C) into high-temperature liquid molten salt (300-400°C). The main principle is that the heat exchanger 2 has a molten salt inlet 21, a molten salt outlet 22, a heat source outlet 23 and a heat source inlet 24. The medium-temperature liquid molten salt enters the heat exchanger 2 from the molten salt inlet 21, and enters with the heat source outlet 23. The heat medium (such as heat conduction oil, hot molten salt) is used for heat exchange, and the medium-temperature liquid molten salt is heated to form high-temperature liquid molten salt, and the high-temperature liquid molten salt is transported to the salt furnace 1 for melting Solid molten salt.

In this embodiment, the temperature of high-temperature molten salt can fluctuate up and down 370 degrees, with a floating range of 70 degrees (up to 600 degrees), and the temperature of medium-temperature salt can fluctuate up and down 310 degrees, with a floating range of 30 degrees.

Specific implementation mode ten:

With reference to the first embodiment, the heat exchanger 2 is a shell-and-tube heat exchanger, a tube-and-tube heat exchanger or a plate heat exchanger.

It should be noted that the terminology used here is only used to describe specific implementations, and is not intended to limit the exemplary implementations according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they mean There are features, steps, operations, means, components and/or combinations thereof.

The relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. At the same time, it should be understood that, for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the Authorized Specification. In all examples shown and discussed herein, any specific values should be construed as illustrative only, and not as limiting. Therefore, other examples of the exemplary embodiment may have different values. It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

In the description of the present invention, it should be understood that orientation words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" etc. indicate the orientation Or positional relationship is generally based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description. In the absence of a contrary description, these orientation words do not indicate or imply the device or element referred to. It must have a specific orientation or be constructed and operated in a specific orientation, so it should not be construed as limiting the protection scope of the present invention; the orientation words "inner and outer" refer to the inner and outer relative to the outline of each component itself.

For the convenience of description, spatially relative terms may be used here, such as "on ...", "over ...", "on the surface of ...", "above", etc., to describe the The spatial positional relationship between one device or feature shown and other devices or features. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, devices described as "above" or "above" other devices or configurations would then be oriented "beneath" or "above" the other devices or configurations. under other devices or configurations". Thus, the exemplary term "above" can encompass both an orientation of "above" and "beneath". The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

It should be noted that the terms "first" and "second" in the description and claims of the present application and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein can be practiced in sequences other than those illustrated or described herein.

It should be noted that, in the above embodiments, as long as the technical solutions that do not contradict each other can be permutated and combined, those skilled in the art can exhaust all possibilities according to the mathematical knowledge of permutations and combinations, so the present invention is no longer concerned with the technical solutions after permutations and combinations. Each will be described, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

This embodiment is only an exemplary description of this patent, and does not limit its protection scope. Those skilled in the art can also make partial changes to it, as long as it does not exceed the spirit and essence of this patent, all within the protection scope of this patent.

Claims

[Corrected 06.08.2021 under Rule 26]
A solar thermal power plant salt melting system based on a natural gas heat transfer oil furnace, characterized in that it includes a salt furnace (1), a heat exchanger (2), a molten salt storage tank (3) and a natural gas heat transfer oil furnace (6) , the heat exchanger (2) has a molten salt inlet (21), a molten salt outlet (22), a heat source outlet (23) and a heat source inlet (24), and the salt furnace (1) passes through a molten salt pipeline (4 ) is connected to the molten salt inlet (21) of the heat exchanger (2), the salt furnace (1) is connected to the molten salt storage tank (3) through the delivery pump (5), and the molten salt outlet (22) of the heat exchanger (2) ) communicates with the chemical salt furnace (1) through the first pipeline (11), and the heat source outlet (23) and heat source inlet (24) of the heat exchanger (2) establish a connection relationship with the natural gas heat-conducting oil furnace (6). The heat conduction oil furnace (6) is used to provide heat exchange heat source for the heat exchanger (2).
[Corrected 06.08.2021 under Rule 26]
A solar thermal power plant salt system based on natural gas heat conduction oil furnace according to claim 1, characterized in that it also includes an auxiliary electric heater (10), the inlet of the auxiliary electric heater (10) and the molten salt pipeline (4) connected, the outlet of the auxiliary electric heater (10) communicates with the salt furnace (1) through the second pipe (12).
[Corrected 06.08.2021 under Rule 26]
A solar thermal power plant salt system based on natural gas heat conduction oil furnace according to claim 2, characterized in that valves (8) are respectively installed on the first pipeline (11) and the second pipeline (12) and temperature measuring instrument (9).
[Corrected 06.08.2021 under Rule 26]
A solar thermal power plant salt conversion system based on natural gas heat conduction oil furnace according to claim 3, characterized in that: the electric energy used in the auxiliary electric heater (10) comes from abandoned wind power, abandoned photovoltaic power or low valley power .
[Corrected 06.08.2021 under Rule 26]
According to claim 1, a solar thermal power plant salt system based on a natural gas heat conduction oil furnace is characterized in that: the number of the heat exchangers (2) is multiple, and the multiple heat exchangers (2) adopt Parallel installation.
[Corrected 06.08.2021 under Rule 26]
According to claim 1, a solar thermal power plant salt system based on a natural gas heat conduction oil furnace is characterized in that: the number of the heat exchangers (2) is multiple, and the multiple heat exchangers (2) adopt Series installation.
[Corrected 06.08.2021 under Rule 26]
A solar thermal power plant salt system based on natural gas heat conduction oil furnace according to claim 5, characterized in that two adjacent heat exchangers (2) are connected through secondary molten salt pipelines (7) .
[Corrected 06.08.2021 under Rule 26]
A solar thermal power plant salt system based on natural gas heat conduction oil furnace according to claim 7, characterized in that: the secondary molten salt pipeline (7) is equipped with a valve (8) and a temperature measuring instrument (9 ).
[Corrected 06.08.2021 under Rule 26]
According to any one of claims 1-2, 5-7, a solar thermal power plant salt salt system based on a natural gas heat transfer oil furnace, characterized in that: the heat exchanger (2) is a shell-and-tube heat exchange heat exchanger, shell and tube heat exchanger or plate heat exchanger.