A high-pressure nitrogen electromagnetic circulation heating device

Abstract

The invention discloses a high-pressure nitrogen electromagnetic circulation heating device, comprising a high-pressure Roots blower and a circulation pipeline, wherein nitrogen is filled in the circulation pipeline, a bypass pipeline is connected between the circulation pipelines, a main circulation pipeline is connected to an inner cavity, and a circulation main loop, a circulation heating loop and an exhaust loop are formed with the bypass pipeline; the high-pressure and high-temperature nitrogen transportation process has a short path and very little heat loss, and because the high-pressure nitrogen has a high thermal conductivity coefficient and a high thermal enthalpy value, the overall electromagnetic circulation heating system has high efficiency, low energy consumption, uniform inner cavity temperature, and no pollution is generated.

Description

Technical Field

[0001] The invention relates to the field of heating equipment, and in particular to a high-pressure nitrogen electromagnetic circulation heating device. Background Art

[0002] Most of the existing pipeline heating is done through superheated steam or boiler steam heating, which requires long-distance transportation, resulting in heat loss, and also produces condensed water, which will cause pollution after contact with the medium; and superheated steam, on the one hand, will have adverse effects on equipment when used directly, and generally cannot be used directly in process production. It needs to be cooled at a steam distribution station, which is costly; boiler steam heating is not environmentally friendly and occupies a large area; at the same time, most of the existing pipeline heating is single-loop heating, without integrated circulation of the loop, which leads to waste of heating energy, low efficiency, and increased heating costs. Summary of the invention

[0003] In order to overcome the above-mentioned shortcomings, the present invention provides a high-pressure nitrogen electromagnetic circulation heating device.

[0004] A high-pressure nitrogen electromagnetic circulation heating device comprises a circulation pipeline and a heating inner cavity; the circulation pipeline sequentially connects the heating inner cavity, a main circulation exhaust valve, a high-pressure Roots blower, a sheath heater and a main circulation air intake valve to form a main circulation loop; a high-pressure normal-temperature nitrogen inlet is provided between the main circulation exhaust valve and the high-pressure Roots blower, a bypass pipeline is connected between the high-pressure normal-temperature nitrogen inlet and the main circulation exhaust valve, the main circulation air intake valve and the sheath heater, a bypass control valve is installed on the bypass pipeline, and a circulation preheating loop is formed by the high-pressure normal-temperature nitrogen inlet, the high-pressure Roots blower, the sheath heater and the bypass control valve connected by the pipeline; a low-pressure normal-temperature nitrogen inlet is provided between the main circulation air intake valve and the heating inner cavity, a low-pressure normal-temperature nitrogen exhaust is provided between the main circulation exhaust valve and the heating inner cavity, and a drying loop is formed by the low-pressure normal-temperature nitrogen inlet, the heating inner cavity and the low-pressure normal-temperature nitrogen exhaust connected by the pipeline.

[0005] According to a preferred embodiment of the present invention, a temperature sensor is provided on the circulating preheating loop.

[0006] According to a preferred embodiment of the present invention, both the low-pressure and normal-temperature nitrogen exhaust port and the high-pressure and normal-temperature nitrogen inlet port are provided with pressure displays.

[0007] According to a preferred embodiment of the present invention, the input shaft end of the Roots blower is connected to a motor, and the motor is connected to a frequency converter.

[0008] The beneficial effects of the present invention are: using high-temperature and high-pressure nitrogen to rush into the heating cavity instead of the original high-pressure steam has very obvious advantages:

[0009] 1. High-temperature nitrogen is heated by a high-efficiency sheath heater installed inside the loop, which has the advantages of high efficiency, low cost, and small footprint. It does not require high-pressure steam for long-distance transmission, and there is no heat loss during the transportation process;

[0010] 2. The high-temperature nitrogen adopts a circulating preheating circuit, which partially overlaps the nitrogen preheating with the system working time, thereby improving the operating efficiency of the system;

[0011] 3. High-temperature and high-pressure nitrogen is transported and pressurized by high-temperature resistant Roots high-pressure blowers. In the second half of the system operation, when less heat is required for the heating process, frequency conversion or shutdown can be used to further save energy.

[0012] 4. After each working cycle is completed, the high-pressure nitrogen can be directly discharged or recycled without causing pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0014] Figure 1 It is a structural schematic diagram of the present invention:

[0015] Figure 2 is a schematic diagram of the exhaust circuit;

[0016] Figure 3 It is a schematic diagram of the cyclic preheating circuit;

[0017] Figure 4 It is a schematic diagram of the main circulation loop;

[0018] Among them: temperature sensor 3, low-pressure and normal-temperature nitrogen inlet 4, main circulation inlet valve 5, sheath heater 6, circulation pipeline 7, Roots blower 8, frequency converter 9, high-pressure and normal-temperature nitrogen inlet 10, main circulation exhaust valve 11, low-pressure and normal-temperature nitrogen exhaust 12, pressure sensor 13, heating inner cavity 14, bypass pipeline 16, bypass control valve 17. DETAILED DESCRIPTION

[0019] The present invention will now be described in further detail with reference to the accompanying drawings. The accompanying drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and thus only show the components related to the present invention.

[0020] In the description of the invention, it should be noted that the terms "upper", "lower", "inside", "outside", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the invention.

[0021] In the description of the invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two components, and a fixed connection can be welding, gluing, etc. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] Example 1

[0023] like Figure 1-4 As shown, a high-pressure nitrogen electromagnetic circulation heating device, a circulation pipeline 7 and a heating cavity 14.

[0024] The circulation pipeline 7 is connected in sequence to the heating inner cavity 14, the main circulation exhaust valve 11, the Roots blower 8, the sheath heater 6 and the main circulation air intake valve 5 to form a main circulation loop; the main circulation air intake valve 5 and the main circulation exhaust valve 11 are provided to control the opening and closing of the circulation pipeline 7. On the one hand, opening and closing allow the high-pressure and normal-temperature nitrogen to enter the heating inner cavity 14 after preheating, and on the other hand, closing allows the high-pressure and normal-temperature nitrogen to enter the preheating loop during the preheating stage.

[0025] For this embodiment, the main circulation air intake valve 5 is opened, the main circulation air exhaust valve 11 is opened, the low-pressure room temperature nitrogen air intake port 4 is closed, the low-pressure room temperature nitrogen air exhaust port 12 is closed, and high-pressure nitrogen is charged from the high-pressure room temperature nitrogen air intake port 10, and after being preheated by the Roots blower 8 and the sheath heater 6, it becomes high-pressure and high-temperature nitrogen and is charged into the heating inner cavity 14.

[0026] Example 2

[0027] The device also includes a bypass pipeline 16. The circulation pipeline between the main circulation exhaust valve 11 and the Roots blower 8 is provided with a high-pressure normal-temperature nitrogen inlet 10. One end of the bypass pipeline 16 is connected to the circulation pipeline between the high-pressure normal-temperature nitrogen inlet 10 and the main circulation exhaust valve 11, and the other end is connected to the circulation pipeline between the main circulation intake valve 5 and the sheath heater 6. A bypass control valve 17 is installed on the bypass pipeline 16; the high-pressure normal-temperature nitrogen inlet 10, the Roots blower 8, the sheath heater 6 and the bypass control valve 17 connected by the pipeline form a circulation preheating loop; the high-pressure normal-temperature nitrogen inlet 10, the Roots blower 8, the sheath heater 6 and the bypass pipeline 16 are provided, and the main circulation loop and the circulation preheating loop are switched through the bypass control valve 17, the main circulation intake valve 5 and the main circulation exhaust valve 11.

[0028] For this embodiment, the main circulation air intake valve 5 is closed, the main circulation exhaust valve 11 is closed, and the bypass control valve 17 is opened, then high-pressure room temperature nitrogen is charged from the high-pressure room temperature nitrogen air inlet 10, and is preheated after passing through the Roots blower 8 and the sheath heater 6. After the charged high-pressure room temperature nitrogen reaches the required temperature, the bypass control valve 17 can be closed, and the main circulation air intake valve 5 and the main circulation exhaust valve 11 can be opened to enter the circulation main loop; at this time, when the circulation preheating loop is working, the drying loop is working at the same time, and the working time of the two loop systems overlaps, thereby improving work efficiency.

[0029] Example 3

[0030] A low-pressure, normal-temperature nitrogen inlet 4 is provided on the circulation pipe 7 between the main circulation air intake valve 5 and the heating inner cavity 14, and a low-pressure, normal-temperature nitrogen exhaust port 12 is provided on the circulation pipe 7 between the main circulation air exhaust valve 11 and the heating inner cavity 14. The low-pressure, normal-temperature nitrogen inlet 4, the heating inner cavity 14 and the low-pressure, normal-temperature nitrogen exhaust port 12 connected by pipes form an exhaust loop; the low-pressure, normal-temperature nitrogen inlet 4 and the low-pressure, normal-temperature nitrogen exhaust port 12 are provided to form an exhaust loop with the pipe to take away the heat generated by the heating inner cavity 14.

[0031] For this embodiment, the low-pressure room-temperature nitrogen inlet 4 is opened, the main circulation inlet valve 5 is closed, the main circulation exhaust valve 11 is closed, and the low-pressure room-temperature nitrogen exhaust port 12 is opened. At this time, the low-pressure room-temperature nitrogen filled in can take away the heat in the heating inner cavity 14.

[0032] The circulating preheating loop is provided with a temperature sensor 3, which can be used to monitor the nitrogen temperature in the pipeline in real time.

[0033] The low-pressure and room-temperature nitrogen exhaust port 12 and the high-pressure and room-temperature nitrogen inlet port 10 are both provided with pressure sensors 13, which can be used to monitor the pressure of the nitrogen in the pipeline in real time to prevent the nitrogen from affecting the uniformity of the temperature inside the heating cavity 14 due to unstable pressure.

[0034] The input shaft end of the Roots blower 8 is connected to a motor, which is connected to a frequency converter 9. In the second half of the system operation, when a heating process with less heat is required, frequency conversion or shutdown can be used to further save energy.

[0035] Working principle: In order to introduce high-temperature nitrogen into the heating cavity, the preheating circulation loop is first opened by switching the bypass valve and the main circulation valve. The preheating circulation loop is composed of a Roots blower and a sheath heater, and the nitrogen to be charged next time is preheated by electromagnetic heating. The nitrogen preheating temperature in the preheating circulation loop is controlled by the temperature sensor equipped in the preheating circulation loop. The nitrogen temperature of the main circuit system is controlled by the temperature sensor equipped on the circulation loop. In order to keep the system pressure stable after the high-temperature nitrogen in the main circuit system is charged into the heating cavity, the pressure of the high-pressure nitrogen input into the system is adjusted by installing a pressure regulating valve at the nitrogen inlet to keep it consistent with the system nitrogen pressure of the main circuit. In order to reduce the power required for nitrogen circulation, a large diameter is selected as much as possible when introducing piping into existing equipment, which can reduce pressure loss. Especially in the second half of the project where less heat is required, the Roots blower can be stopped.

[0036] The above is based on the present invention as an inspiration. Through the above description, relevant staff can make various changes and modifications without departing from the technical idea of ​​this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A high-pressure nitrogen electromagnetic circulation heating device, comprising a circulation pipeline and a heating inner cavity (14); characterized in that: The circulation pipeline (7) is connected end to end with the heating inner cavity (14), the main circulation exhaust valve (11), the high-pressure Roots blower (8), the sheath heater (6) and the main circulation air intake valve (5) to form a main circulation loop; it also includes a bypass pipeline (16), the circulation pipeline between the main circulation exhaust valve (11) and the high-pressure Roots blower (8) is provided with a high-pressure normal temperature nitrogen inlet (10), one end of the bypass pipeline (16) is connected to the circulation pipeline between the high-pressure normal temperature nitrogen inlet (10) and the main circulation exhaust valve (11), and the other end is connected to the circulation pipeline between the main circulation air intake valve (5) and the sheath heater (6), and a bypass control valve (17) is installed on the bypass pipeline (16); the high-pressure normal temperature nitrogen inlet (10), the high-pressure Roots blower (8), the sheath heater (6) and the bypass control valve (17) connected by the pipeline form a circulation preheating loop; A low-pressure, normal-temperature nitrogen inlet (4) is provided on the circulation pipe (7) between the main circulation air inlet valve (5) and the heating inner cavity (14), and a low-pressure, normal-temperature nitrogen exhaust port (12) is provided on the circulation pipe (7) between the main circulation air exhaust valve (11) and the heating inner cavity (14). The low-pressure, normal-temperature nitrogen inlet (4), the heating inner cavity (14) and the low-pressure, normal-temperature nitrogen exhaust port (12) connected by pipes form a drying circuit; a temperature sensor (3) is provided on the circulation preheating circuit, and pressure sensors (13) are provided on the low-pressure, normal-temperature nitrogen exhaust port (12) and the high-pressure, normal-temperature nitrogen inlet (10).

2. A high-pressure nitrogen electromagnetic circulation heating device according to claim 1, characterized in that: The input shaft end of the Roots blower (8) is connected to an electric motor, and the electric motor is connected to a frequency converter (9).

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