Low-pressure self-starting liquid nitrogen water bath electric heating system

Abstract

The utility model discloses a low-pressure self-starting liquid nitrogen water bath electric heating system which comprises a liquid nitrogen storage tank, the liquid nitrogen storage tank is connected with a nitrogen storage tank through a nitrogen conveying module, the nitrogen storage tank is connected with a nitrogen pipe network, a low-pressure linkage control system is arranged between the nitrogen storage tank and the nitrogen pipe network, and the nitrogen conveying module is connected with a gasification system. According to the low-pressure self-starting liquid nitrogen water bath electric heating system, the emergency response of self-starting preheating of a liquid nitrogen water bath type gasifier and an electric heater is achieved, and nitrogen of a nitrogen pipe network can be supplemented in time under the sudden working condition; the operation time of the liquid nitrogen water bath type vaporizer and the heater can be effectively shortened, the service life of equipment is prolonged, and equipment maintenance consumption and labor cost are greatly reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquid nitrogen heating equipment and relates to a low-pressure self-starting liquid nitrogen water bath electric heating system. Background Art

[0002] The common engineering nitrogen in chemical enterprises is a relatively common and important auxiliary material. For liquefied natural gas plants, nitrogen is commonly used in scenarios such as the isolation gas of centrifugal compressor units, the positive pressure protection of explosion-proof motor junction boxes, and the pressure maintenance of storage tanks. It is a key factor to ensure the safe and stable operation of relevant equipment and systems. Therefore, it is very important to keep the pressure of the nitrogen system pipeline network in a stable state in daily production safety control work. An air compressor unit, a nitrogen production unit, and a nitrogen storage tank are set up on site. At the same time, to ensure that the nitrogen pipeline network pressure is stable above the safety line required for production in case of sudden failures of the air compressor unit and the nitrogen production machine, the factory is equipped with two sets of liquid nitrogen vaporization devices. Each vaporization device consists of an air-cooled vaporizer + a water bath vaporizer. After the unit fails and shuts down, the operator goes to the site to start the liquid nitrogen vaporization device to supplement the pressure of the nitrogen pipeline network. Due to the accidental and sudden characteristics of the nitrogen production unit failure, and it takes about 30 minutes from startup to fully function, there is a safety risk that the nitrogen system pressure cannot be supplemented and stabilized in time. Currently, for the sake of insurance, the operator keeps the liquid nitrogen water bath electric heater on all year round. Although the purpose of having the liquid nitrogen water bath vaporizer ready for use at any time is achieved, it also causes various problems with the equipment. Mainly, it causes losses and waste of electric energy and electricity bills, accelerates the aging of electrical equipment and shortens its service life, increases the equipment failure rate, increases the daily maintenance and repair costs of the heater, and at the same time, there are risks in the reliability and safety of liquid nitrogen vaporization and pressure supplementation, which in turn affects the safe and stable operation of the overall production line.

[0003] In summary, the prior art has the problem that the liquid nitrogen vaporizer cannot supplement nitrogen in time under sudden working conditions. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a low-pressure self-starting liquid nitrogen water bath electric heating system, which solves the problem that the liquid nitrogen vaporizer in the prior art cannot supplement nitrogen in time under sudden working conditions.

[0005] The technical solution adopted by the utility model is that the low-pressure self-starting liquid nitrogen water bath electric heating system includes a liquid nitrogen storage tank. The liquid nitrogen storage tank is connected to a nitrogen storage tank through a nitrogen delivery module. The nitrogen storage tank is connected to a nitrogen pipeline network. A low-pressure linkage control system is arranged between the nitrogen storage tank and the nitrogen pipeline network. The nitrogen delivery module is connected to a vaporization system.

[0006] The characteristics of the utility model also lie in:

[0007] The low-pressure linkage control system includes a pressure transmitter sensor, which is arranged between the nitrogen storage tank and the nitrogen pipeline network. The pressure transmitter sensor is connected to the pressure controller through a signal transmission line.

[0008] The gasification system comprises a water bath gasifier, which is communicated with a nitrogen delivery module.

[0009] An electric heater is arranged in the water bath type vaporizer, and the electric heater is connected to an electric heater controller.

[0010] The electric heater controller is connected to the pressure controller through a signal transmission line.

[0011] The gasification system also includes an air-temperature gasifier, which is connected to the liquid nitrogen storage tank and the nitrogen delivery module respectively.

[0012] The beneficial effects of the utility model are as follows: the utility model innovates the system control mode of the electric heating device of the liquid nitrogen water bath vaporizer, realizes the emergency response of the liquid nitrogen water bath vaporizer and the electric heater to start preheating automatically, and can replenish the nitrogen of the nitrogen pipeline network in time in the event of an emergency; the utility model can effectively shorten the operation time of the liquid nitrogen water bath vaporizer and the heater, prolong the life of the equipment, and greatly reduce the equipment maintenance consumption and labor cost; the utility model effectively reduces the adverse effects caused by human factors under emergency conditions through the system automatic response, and the safety production operation benefits are obvious; the data acquisition instrument and electrical control equipment in the utility model are mature in technology, strong in stability, and have a high safety factor for long-term use; the pressure acquisition and information linkage system has a small amount of data processing, the system failure rate is low, and the overall device runs stably; the utility model can be integrated with the original process flow, and only a small modification is required to realize system access and linkage, which is convenient for application in the liquid nitrogen gasification device system of a liquefied natural gas plant, and is not affected by various factors such as the location of the device and the distribution of the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The utility model is a structural schematic diagram of a low-pressure self-starting liquid nitrogen water bath electric heating system.

[0014] 1. Liquid nitrogen storage tank; 2. Air temperature vaporizer; 3. Nitrogen delivery module; 4. Nitrogen storage tank; 5. Pressure transmitter sensor; 6. Pressure controller; 7. Signal transmission line; 8. Water bath vaporizer; 9. Electric heater controller; 10. Nitrogen pipeline network; 11. Electric heater. DETAILED DESCRIPTION

[0015] The utility model is described in detail below with reference to the accompanying drawings and specific implementation modes.

[0016] Liquid low pressure self-starting liquid nitrogen water bath electric heating system, such as Figure 1As shown in the figure, it includes a liquid nitrogen storage tank 1. The liquid nitrogen storage tank 1 is connected to a nitrogen storage tank 4 through a nitrogen delivery module 3. The nitrogen storage tank 4 is connected to a nitrogen pipeline network 10. A low-pressure interlock control system is provided between the nitrogen storage tank 4 and the nitrogen pipeline network 10. The nitrogen delivery module 3 is connected to a vaporization system.

[0017] The low-pressure interlock control system includes a pressure transmitting sensor 5. The pressure transmitting sensor 5 is arranged between the nitrogen storage tank 4 and the nitrogen pipeline network 10. The pressure transmitting sensor 5 is connected to a pressure controller 6 through a signal transmission line 7. The vaporization system includes a water bath vaporizer 8. The water bath vaporizer 8 is communicated with the nitrogen delivery module 3. An electric heater 11 is arranged inside the water bath vaporizer 8. The electric heater 11 is connected to an electric heater controller 9. The electric heater controller 9 is connected to the pressure controller 6 through a signal transmission line 7. The vaporization system also includes an air-cooled vaporizer 2. The air-cooled vaporizer 2 is respectively communicated with the liquid nitrogen storage tank 1 and the nitrogen delivery module 3.

[0018] The liquid nitrogen storage tank 1 is used for storing liquid nitrogen; the air-cooled vaporizer 2 vaporizes liquid nitrogen through air heat exchange, and the formed gaseous nitrogen is transported to the nitrogen storage tank 4 through the nitrogen delivery module 3; the nitrogen stored in the nitrogen storage tank 4 is used to keep the pressure of the entire nitrogen pipeline network 10 stable; the pressure transmitting sensor 5 is used for collecting the pressure value of the nitrogen pipeline network 10; the pressure transmitting sensor 5 transmits the collected pressure value of the nitrogen pipeline network 10 to the pressure controller 6; the pressure controller 6 analyzes and transmits a signal to the electric heater controller 9, and starts the electric heater 11 through the electric heater controller 9; the electric heater controller 9 is used for controlling the switch of the electric heater 11; the electric heater 11 is installed inside the water bath vaporizer 8 and is used for heating the water in the water bath vaporizer 8; the water bath vaporizer 8 and the nitrogen delivery module 3 are connected by pipeline welding, and the nitrogen obtained after the liquid nitrogen is vaporized by the water bath vaporizer 8 is transported to the nitrogen storage tank 4 through the nitrogen delivery module 3 again, and the nitrogen stored in the nitrogen storage tank 4 is used to keep the pressure of the entire nitrogen pipeline network 10 stable.

[0019] The working principle of the present utility model is as follows:

[0020] The pressure transmitting sensor 5 collects the pressure value of the nitrogen pipeline network 10 and transmits it to the pressure controller 6. A reference value is set inside the pressure controller 6. When the pressure is lower than the reference value, the pressure controller 6 transmits a signal to the electric heater controller 9, and the electric heater controller 9 starts the electric heater 11 to heat the water inside the water bath vaporizer 8, realizing the automatic start of the electric heating system of the water bath vaporizer when the pipeline network is at low pressure.

[0021] The liquid nitrogen in the liquid nitrogen storage tank 1 is initially vaporized by the air-cooled vaporizer 2, and then enters the water bath vaporizer 8 for complete vaporization. The gaseous nitrogen is transported to the nitrogen storage tank 4 for storage through the nitrogen delivery module 3, and the nitrogen in the nitrogen storage tank 4 continuously supplements the pressure stability of the nitrogen pipeline network 10.

[0022] The low-pressure linkage control system designed by the utility model is convenient to be connected to various liquid nitrogen supply systems. On the basis that the water bath vaporizer 8 and the electric heater 11 do not need to be opened for standby for a long time, it also has the function of automatically linking and starting the water bath vaporizer 8 and the electric heater 11 when the pressure of the nitrogen pipeline network is too low, which can ensure the timeliness and safety and reliability of pressure replenishment when the pressure of the nitrogen pipeline network is too low while greatly reducing the electricity cost and equipment loss. The utility model directly uses the existing pressure taking points of the pipeline in the nitrogen pipeline network of the chemical plant to transform and install the pressure transmitter sensor 5, and the pressure controller 6 can be directly connected to the electric heater controller 9, which solves the problem of the water bath vaporizer 8 and the electric heater 11 being opened all year round from the source, directly reduces the opening time of the electric heater 11, and has the function of the low-pressure self-starting electric heater 11, ensuring that the water temperature is raised in advance, ensuring the normal operation of the water bath vaporizer 8, thereby greatly reducing the electricity consumption cost and extending the life of the equipment, safely and reliably ensuring the stable supply of nitrogen pipeline network pressure, and further ensuring the safe and stable operation of the main equipment of the factory.

[0023] Example 1

[0024] like Figure 1 As shown, this embodiment proposes a low-pressure self-starting liquid nitrogen water bath electric heating system, including a liquid nitrogen storage tank 1, the liquid nitrogen storage tank 1 is connected to a nitrogen storage tank 4 through a nitrogen delivery module 3, the nitrogen storage tank 4 is connected to a nitrogen pipeline network 10, a low-pressure linkage control system is arranged between the nitrogen storage tank 4 and the nitrogen pipeline network 10, and the nitrogen delivery module 3 is connected to a gasification system.

[0025] Example 2

[0026] like Figure 1 As shown, this embodiment proposes a low-pressure self-starting liquid nitrogen water bath electric heating system, including a liquid nitrogen storage tank 1, the liquid nitrogen storage tank 1 is connected to a nitrogen storage tank 4 through a nitrogen delivery module 3, the nitrogen storage tank 4 is connected to a nitrogen pipe network 10, a low-pressure linkage control system is arranged between the nitrogen storage tank 4 and the nitrogen pipe network 10, and the nitrogen delivery module 3 is connected to a gasification system. The low-pressure linkage control system includes a pressure transmitter sensor 5, the pressure transmitter sensor 5 is arranged between the nitrogen storage tank 4 and the nitrogen pipe network 10, and the pressure transmitter sensor 5 is connected to a pressure controller 6 through a signal transmission line 7. The gasification system includes a water bath gasifier 8, and the water bath gasifier 8 is connected to the nitrogen delivery module 3.

[0027] Example 3

[0028] like Figure 1As shown, this embodiment proposes a low-pressure self-starting liquid nitrogen water bath electric heating system, including a liquid nitrogen storage tank 1, the liquid nitrogen storage tank 1 is connected to a nitrogen storage tank 4 through a nitrogen delivery module 3, the nitrogen storage tank 4 is connected to a nitrogen pipe network 10, a low-pressure linkage control system is arranged between the nitrogen storage tank 4 and the nitrogen pipe network 10, and the nitrogen delivery module 3 is connected to a gasification system. The low-pressure linkage control system includes a pressure transmitter sensor 5, the pressure transmitter sensor 5 is arranged between the nitrogen storage tank 4 and the nitrogen pipe network 10, and the pressure transmitter sensor 5 is connected to a pressure controller 6 through a signal transmission line 7. The gasification system includes a water bath gasifier 8, and the water bath gasifier 8 is connected to the nitrogen delivery module 3. An electric heater 11 is arranged in the water bath gasifier 8, and the electric heater 11 is connected to an electric heater controller 9. The electric heater controller 9 is connected to the pressure controller 6 through a signal transmission line 7. The gasification system also includes an air temperature gasifier 2, and the air temperature gasifier 2 is respectively connected to the liquid nitrogen storage tank 1 and the nitrogen delivery module 3.

Claims

1. Low-pressure self-starting liquid nitrogen water bath electric heating system, characterized in that: The invention comprises a liquid nitrogen storage tank (1), wherein the liquid nitrogen storage tank (1) is connected to a nitrogen storage tank (4) via a nitrogen delivery module (3), the nitrogen storage tank (4) is connected to a nitrogen pipe network (10), a low-pressure linkage control system is arranged between the nitrogen storage tank (4) and the nitrogen pipe network (10), and the nitrogen delivery module (3) is connected to a gasification system.

2. The low-pressure self-starting liquid nitrogen water bath electric heating system according to claim 1 is characterized in that: The low-pressure linkage control system comprises a pressure transmitter sensor (5), wherein the pressure transmitter sensor (5) is arranged between a nitrogen storage tank (4) and a nitrogen pipe network (10), and the pressure transmitter sensor (5) is connected to a pressure controller (6) via a signal transmission line (7).

3. The low-pressure self-starting liquid nitrogen water bath electric heating system according to claim 2 is characterized in that: The gasification system comprises a water bath gasifier (8), and the water bath gasifier (8) is connected to a nitrogen delivery module (3).

4. The low-pressure self-starting liquid nitrogen water bath electric heating system according to claim 3 is characterized in that: An electric heater (11) is arranged in the water bath vaporizer (8), and the electric heater (11) is connected to an electric heater controller (9).

5. The low-pressure self-starting liquid nitrogen water bath electric heating system according to claim 4 is characterized in that: The electric heater controller (9) is connected to the pressure controller (6) via a signal transmission line (7).

6. The low-pressure self-starting liquid nitrogen water bath electric heating system according to claim 5 is characterized in that: The gasification system further comprises an air-temperature gasifier (2), and the air-temperature gasifier (2) is respectively connected to the liquid nitrogen storage tank (1) and the nitrogen delivery module (3).

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