Nitrogen sealing system of electric heating heat medium furnace

Abstract

The utility model discloses a nitrogen sealing system of an electric heating heat medium furnace, which comprises a low-pressure emergency recovery tank, a high-pressure heat medium cooler, a low-pressure heat medium cooler, a first regulating valve, a second regulating valve, a third regulating valve and a fourth regulating valve, an air inlet of the high-pressure heat medium cooler is communicated with an inner cavity of the electric heating heat medium furnace body through a second pipeline, an air outlet of the first adjusting valve is communicated with an air inlet of the low-pressure heat medium cooler through a third pipeline, and an air outlet of the low-pressure heat medium cooler is communicated with an inner cavity of the tank body through a fourth pipeline. A gas inlet of the second regulating valve is communicated with a high-pressure nitrogen source through a fifth pipeline, a gas outlet of the second regulating valve is communicated with a gas outlet of the high-pressure heating medium cooler through a sixth pipeline, a gas outlet of the third regulating valve and a gas inlet of the fourth regulating valve are communicated with an inner cavity of the tank body, and a gas inlet of the third regulating valve is communicated with a low-pressure nitrogen source. During emergency discharge, safe recovery of the heating medium can be ensured, and fire accidents are avoided.

Description

Technical Field

[0001] This utility model relates to an electric heating heat medium furnace, and more particularly to a nitrogen sealing system for an electric heating heat medium furnace with gas phase heat medium, belonging to the field of industrial boiler technology. Background Technology

[0002] In May 2024, the State Council issued a notice on the "Action Plan for Energy Conservation and Carbon Reduction in 2024-2025," which clearly stated that the proportion of non-fossil energy consumption in newly launched high-energy-consuming projects in the last two years of the "14th Five-Year Plan" should not be less than 20%. In October 2024, the National Energy Administration and other departments issued the "Guiding Opinions on Vigorously Implementing Renewable Energy Substitution Action," which pointed out that it is necessary to accelerate the construction of large-scale wind and solar power bases, focusing on desert, Gobi, and arid areas, promote the cluster development of offshore wind power, scientifically and orderly promote the construction of large-scale hydropower bases, coordinate the integrated development of water, wind, and solar power, and develop distributed renewable energy nearby.

[0003] With the National Development and Reform Commission and other departments actively promoting pilot projects for renewable energy substitution and innovation, accelerating the pilot application of offshore wind power and ground photovoltaic power projects, promoting the deep integration of solar thermal power with wind and solar power, and promoting green electricity consumption, the demand for green electricity trading has steadily increased, and electric heating heat transfer medium furnaces have been widely used and promoted.

[0004] Electric heating heat transfer fluid furnaces are widely used in heating, drying, or softening processes in food, chemical fiber, and petrochemical industries. With the increasing prevalence of electric heating heat transfer fluid furnaces, especially in processes requiring strict heat exchange temperature differences, they are recommended due to the high heat exchange efficiency of gaseous heat transfer fluid condensation. However, existing nitrogen sealing systems for electric heating heat transfer fluid furnaces have two main drawbacks in practical operation: Firstly, the nitrogen pressure used for sealing within the furnace body is often unstable, leading to a short lifespan of the heat transfer fluid and low heat exchange efficiency. Secondly, when the pressure of the gaseous heat transfer fluid and nitrogen within the furnace body becomes too high and requires emergency venting, the gaseous heat transfer fluid is directly released into the atmosphere, easily causing a fire and endangering the safety of the enterprise. Summary of the Invention

[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide an electrically heated heat medium furnace nitrogen sealing system that can ensure stable nitrogen pressure for nitrogen sealing and ensure safe recovery of the heat medium in the system during emergency discharge, without causing a fire accident.

[0006] To solve the above-mentioned technical problems, this utility model adopts an electric heating heat medium furnace nitrogen sealing system, including an electric heating heat medium furnace body. A heat medium, an electric heating element for heating the heat medium, and nitrogen gas for nitrogen sealing are disposed within the inner cavity of the electric heating heat medium furnace body. It also includes a low-pressure emergency recovery tank, a high-pressure heat medium cooler, a low-pressure heat medium cooler, a first regulating valve, a second regulating valve, a third regulating valve, and a fourth regulating valve. The low-pressure emergency recovery tank has a sealed tank body, and low-pressure nitrogen gas is stored in the inner cavity of the tank body. The inlet of the first regulating valve is connected to the outlet of the high-pressure heat medium cooler through a first pipeline. The air inlet of the cooler is connected to the inner cavity of the electric heating medium furnace body through a second pipeline. The air outlet of the first regulating valve is connected to the air inlet of the low-pressure medium cooler through a third pipeline. The air outlet of the low-pressure medium cooler is connected to the inner cavity of the tank body through a fourth pipeline. The air inlet of the second regulating valve is connected to the high-pressure nitrogen source through a fifth pipeline. The air outlet of the second regulating valve is connected to the air outlet of the high-pressure medium cooler through a sixth pipeline. The air outlet of the third regulating valve and the air inlet of the fourth regulating valve are connected to the inner cavity of the tank body through a seventh pipeline. The air inlet of the third regulating valve is connected to the low-pressure nitrogen source through an eighth pipeline.

[0007] In a preferred embodiment of this utility model, the nitrogen pressure value of the high-pressure nitrogen source and the nitrogen pressure value of the nitrogen used for nitrogen sealing in the inner cavity of the electric heating heat medium furnace body are 0.8 to 1.0 MPa, and the nitrogen pressure value of the low-pressure nitrogen source and the nitrogen pressure value of the low-pressure nitrogen in the inner cavity of the tank body are 0.1 to 0.2 MPa.

[0008] In a preferred embodiment of this utility model, the first regulating valve, the second regulating valve, the third regulating valve and the fourth regulating valve are self-operated pressure regulating valves.

[0009] In a preferred embodiment of this utility model, a first pressure sensor for measuring the nitrogen pressure in the inner cavity of the electric heating heat medium furnace body is provided on the top of the electric heating heat medium furnace body, and a second pressure sensor for measuring the nitrogen pressure in the inner cavity of the tank body is provided on the top of the tank body. The first pressure sensor, the second pressure sensor, the first regulating valve, the second regulating valve, the third regulating valve and the fourth regulating valve are all electrically connected to the electric controller of the electric heating heat medium furnace.

[0010] In a preferred embodiment of this utility model, the electric controller of the electric heating heat medium furnace is a digital controller, an embedded industrial controller, an industrial computer, or a PLC programmable controller.

[0011] In a preferred embodiment of this utility model, the high-pressure heat medium cooler and the low-pressure heat medium cooler are cooling water coolers or air coolers.

[0012] By adopting the above structure, this utility model has the following beneficial effects:

[0013] This utility model includes a low-pressure emergency recovery tank, a high-pressure heat medium cooler, a low-pressure heat medium cooler, a first regulating valve, a second regulating valve, a third regulating valve, and a fourth regulating valve. The inlet of the first regulating valve is connected to the outlet of the high-pressure heat medium cooler via a first pipeline. The inlet of the high-pressure heat medium cooler is connected to the inner cavity of the electric heating heat medium furnace via a second pipeline. The outlet of the first regulating valve is connected to the inlet of the low-pressure heat medium cooler via a third pipeline. The outlet of the low-pressure heat medium cooler is connected to the inner cavity of the tank via a fourth pipeline. The inlet of the second regulating valve is connected to a high-pressure nitrogen source via a fifth pipeline. The outlet of the second regulating valve is connected to the outlet of the high-pressure heat medium cooler via a sixth pipeline. The outlet of the third regulating valve and the inlet of the fourth regulating valve are connected to the inner cavity of the tank via a seventh pipeline. The inlet of the third regulating valve is connected to a low-pressure nitrogen source via an eighth pipeline. During operation, when the pressure of the gaseous heat medium and nitrogen in the internal cavity of the electric heating heat medium furnace is too high, preferably exceeding the set range, and emergency discharge is required, the first regulating valve automatically opens, or the first pressure sensor transmits a pressure signal to the electronic controller. The electronic controller then controls the first regulating valve to open. The gaseous heat medium and excess nitrogen sequentially pass through the second pipeline, the high-pressure heat medium cooler, the first pipeline, the first regulating valve, the third pipeline, the low-pressure heat medium cooler, and the fourth pipeline into the low-pressure emergency recovery tank. In other words, on the one hand, the gaseous heat medium first passes through the pipeline into the high-pressure heat medium cooler for primary cooling, and then passes through the pipeline into the low-pressure heat medium cooler for secondary cooling. After cooling down, the gaseous heat medium becomes liquid and is safely stored in the low-pressure emergency recovery tank, ensuring the safety of the system and preventing fire accidents that could endanger the safety of the enterprise. On the other hand, excess nitrogen enters the low-pressure emergency recovery tank, saving nitrogen. When the nitrogen pressure in the inner cavity of the electric heating heat medium furnace is too low, preferably below the set range, the second regulating valve automatically opens or the first pressure sensor transmits a pressure signal to the electronic controller, which then controls the second regulating valve to open. High-pressure nitrogen from the high-pressure nitrogen source enters the inner cavity of the electric heating heat medium furnace in sequence through the fifth pipeline, the second regulating valve, the sixth pipeline, the high-pressure heat medium cooler, and the second pipeline to replenish the high-pressure nitrogen, ensuring that the nitrogen pressure in the inner cavity of the electric heating heat medium furnace is within the set range. This ensures the stability of the nitrogen pressure used for nitrogen sealing and guarantees the service life and heat exchange efficiency of the heat medium. In addition, when the nitrogen pressure in the low-pressure emergency recovery tank is too high, preferably higher than the set range, the fourth regulating valve will automatically open or the second pressure sensor will transmit a pressure signal to the electronic controller, which will then control the fourth regulating valve to release the excess nitrogen. When the nitrogen pressure in the low-pressure emergency recovery tank is too low, preferably lower than the set range, the third regulating valve will automatically open or the second pressure sensor will transmit a pressure signal to the electronic controller, which will then control the third regulating valve to replenish the low-pressure nitrogen, ensuring that the nitrogen pressure in the low-pressure emergency recovery tank is within the set range.

[0014] This invention features a high-pressure heat transfer medium cooler and a low-pressure heat transfer medium cooler, providing two-stage temperature and pressure reduction. In case of emergency discharge, it ensures that the gaseous heat transfer medium is cooled and safely recovered, greatly improving safety.

[0015] This novel nitrogen blanketing system is safe and reliable, and has a simple structure and is easy to manufacture, which is conducive to its widespread application. Attached Figure Description

[0016] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the structure of the nitrogen sealing system for the electric heating heat medium furnace of this utility model. Detailed Implementation

[0018] See Figure 1 The diagram illustrates a nitrogen sealing system for an electrically heated heat medium furnace. It includes an electrically heated heat medium furnace body 1, within which a heat medium 1-1 (e.g., biphenyl, diphenyl ether) and an electric heating element 1-2 (e.g., an electric heating tube) for heating the heat medium 1-1 are disposed, along with nitrogen gas for nitrogen sealing. The system also includes a low-pressure emergency recovery tank 2, a high-pressure heat medium cooler 3, a low-pressure heat medium cooler 4, a first regulating valve 5, a second regulating valve 6, a third regulating valve 7, and a fourth regulating valve 8. The low-pressure emergency recovery tank 2 has a sealed tank 2-1, within which low-pressure nitrogen gas is stored. The inlet of the first regulating valve 5 is connected to the outlet 3-1 of the high-pressure heat medium cooler 3 via a first pipe 9. The inlet 3-1 of the high-pressure heat medium cooler 3... 2. The first regulating valve 5 is connected to the inner cavity of the electric heating medium furnace body 1 through the second pipeline 10. The outlet of the first regulating valve 5 is connected to the inlet 4-1 of the low-pressure medium cooler 4 through the third pipeline 11. The outlet 4-2 of the low-pressure medium cooler 4 is connected to the inner cavity of the tank 2-1 through the fourth pipeline 12. The inlet of the second regulating valve 6 is connected to the high-pressure nitrogen source 17 through the fifth pipeline 13. The outlet of the second regulating valve 6 is connected to the outlet 3-1 of the high-pressure medium cooler 3 through the sixth pipeline 14. The outlet of the third regulating valve 7 and the inlet of the fourth regulating valve 8 are connected to the inner cavity of the tank 2-1 through the seventh pipeline 15. The inlet of the third regulating valve 7 is connected to the low-pressure nitrogen source 18 through the eighth pipeline 16.

[0019] In a preferred embodiment of this utility model, the nitrogen pressure value of the high-pressure nitrogen source 17 and the nitrogen pressure value for nitrogen sealing in the inner cavity of the electric heating heat medium furnace body 1 are 0.8 to 1.0 MPa, and the nitrogen pressure value of the low-pressure nitrogen source 18 and the nitrogen pressure value of low-pressure nitrogen in the inner cavity of the tank 2-1 are 0.1 to 0.2 MPa.

[0020] In the first preferred embodiment of this utility model, the first regulating valve 5, the second regulating valve 6, the third regulating valve 7 and the fourth regulating valve 8 are self-operated pressure regulating valves.

[0021] In a second preferred embodiment of this utility model, a first pressure sensor 19 for measuring the nitrogen pressure in the inner cavity of the electric heating heat medium furnace body 1 is provided on the top of the electric heating heat medium furnace body 1, and a second pressure sensor 20 for measuring the nitrogen pressure in the inner cavity of the tank 2-1 is provided on the top of the tank 2-1. The first pressure sensor 19, the second pressure sensor 20, the first regulating valve 5, the second regulating valve 6, the third regulating valve 7, and the fourth regulating valve 8 are all electrically connected to the electric controller of the electric heating heat medium furnace (the electric controller is not shown in the figure). The first regulating valve 5, the second regulating valve 6, the third regulating valve 7, and the fourth regulating valve 8 can be electric regulating valves or pneumatic regulating valves, etc.

[0022] In a preferred embodiment of this utility model, the electric controller of the electric heating heat medium furnace is a digital controller, such as a DDC digital controller, an embedded industrial controller, an industrial computer, or a PLC programmable controller.

[0023] In a preferred embodiment of this utility model, the high-pressure heat transfer medium cooler 3 and the low-pressure heat transfer medium cooler 4 are cooling water coolers or air coolers, etc. Preferably, the high-pressure heat transfer medium cooler 3 and the low-pressure heat transfer medium cooler 4 of this utility model are cooling water coolers, such as… Figure 1 As shown, one cooling water path enters the high-pressure heat transfer medium cooler 3 through pipe 21, and after heat exchange, it is discharged from the high-pressure heat transfer medium cooler 3 through pipe 22. The cooling water is preferably circulated by a circulating pump. The other cooling water path enters the low-pressure heat transfer medium cooler 4 through pipe 23, and after heat exchange, it is discharged from the low-pressure heat transfer medium cooler 4 through pipe 24. The cooling water is preferably circulated by a circulating pump.

[0024] When this utility model is in operation, if the pressure of the gaseous heat medium and nitrogen in the inner cavity of the electric heating heat medium furnace body 1 is too high and requires emergency discharge, the first regulating valve 5 will automatically open or the first pressure sensor 19 will transmit the pressure signal to the electronic controller, which will then control the first regulating valve 5 to open. The gaseous heat medium and excess nitrogen will sequentially enter the low-pressure emergency recovery tank 2 through the second pipeline 10, the high-pressure heat medium cooler 3, the first pipeline 9, the first regulating valve 5, the third pipeline 11, the low-pressure heat medium cooler 4, and the fourth pipeline 12. The gaseous heat medium is cooled once by the high-pressure heat medium cooler 3 and then cooled a second time by the low-pressure heat medium cooler 4. After cooling down, the gaseous heat medium becomes liquid and is safely stored in the low-pressure emergency recovery tank 2, ensuring the safety of the system.

[0025] After trial use, this utility model can ensure the safe recovery of the heat transfer medium in the system during emergency discharge, avoiding fire accidents, and the nitrogen pressure used for nitrogen sealing is stable, achieving good practical results.

Claims

1. A nitrogen sealing system for an electrically heated heat medium furnace, comprising an electrically heated heat medium furnace body (1), wherein a heat medium (1-1) and an electrically heated element (1-2) for heating the heat medium (1-1) and nitrogen gas for nitrogen sealing are disposed in the inner cavity of the electrically heated heat medium furnace body (1), characterized in that: It also includes a low-pressure emergency recovery tank (2), a high-pressure heat medium cooler (3), a low-pressure heat medium cooler (4), a first regulating valve (5), a second regulating valve (6), a third regulating valve (7), and a fourth regulating valve (8). The low-pressure emergency recovery tank (2) has a sealed tank (2-1) in which low-pressure nitrogen is stored. The inlet of the first regulating valve (5) is connected to the outlet (3-1) of the high-pressure heat medium cooler (3) through a first pipe (9). The inlet (3-2) of the high-pressure heat medium cooler (3) is connected to the inner cavity of the electric heating heat medium furnace body (1) through a second pipe (10). The outlet of the first regulating valve (5) is connected to the inner cavity of the electric heating heat medium furnace body (1) through a third pipe (11). The inlet (4-1) of the low-pressure heat medium cooler (4) is connected to the outlet (4-2) of the low-pressure heat medium cooler (4) and is connected to the inner cavity of the tank (2-1) through the fourth pipeline (12). The inlet of the second regulating valve (6) is connected to the high-pressure nitrogen source (17) through the fifth pipeline (13). The outlet of the second regulating valve (6) is connected to the outlet (3-1) of the high-pressure heat medium cooler (3) through the sixth pipeline (14). The outlet of the third regulating valve (7) and the inlet of the fourth regulating valve (8) are connected to the inner cavity of the tank (2-1) through the seventh pipeline (15). The inlet of the third regulating valve (7) is connected to the low-pressure nitrogen source (18) through the eighth pipeline (16).

2. The nitrogen sealing system for an electrically heated heat transfer medium furnace according to claim 1, characterized in that: The nitrogen pressure value of the high-pressure nitrogen source (17) and the nitrogen pressure value of the nitrogen used for nitrogen sealing in the inner cavity of the electric heating heat medium furnace body (1) are 0.8 to 1.0 MPa, and the nitrogen pressure value of the low-pressure nitrogen source (18) and the nitrogen pressure value of the low-pressure nitrogen in the inner cavity of the tank (2-1) are 0.1 to 0.2 MPa.

3. The nitrogen sealing system for an electrically heated heat transfer medium furnace according to claim 1, characterized in that: The first regulating valve (5), the second regulating valve (6), the third regulating valve (7) and the fourth regulating valve (8) are self-operated pressure regulating valves.

4. The nitrogen sealing system for an electrically heated heat transfer medium furnace according to claim 1, characterized in that: A first pressure sensor (19) for measuring the nitrogen pressure in the inner cavity of the electric heating heat medium furnace body (1) is provided on the top of the electric heating heat medium furnace body (1), and a second pressure sensor (20) for measuring the nitrogen pressure in the inner cavity of the tank body (2-1) is provided on the top of the tank body (2-1). The first pressure sensor (19), the second pressure sensor (20), the first regulating valve (5), the second regulating valve (6), the third regulating valve (7) and the fourth regulating valve (8) are all electrically connected to the electric controller of the electric heating heat medium furnace.

5. The nitrogen sealing system for an electrically heated heat transfer medium furnace according to claim 4, characterized in that: The electrical controller of the electric heating heat medium furnace is a digital controller, an embedded industrial controller, an industrial computer, or a PLC programmable controller.

6. The nitrogen sealing system for an electrically heated heat transfer medium furnace according to any one of claims 1 to 5, characterized in that: The high-pressure heat medium cooler (3) and the low-pressure heat medium cooler (4) are either cooling water coolers or air coolers.

Images