CN221279206U - Liquid nitrogen vaporization system - Google Patents

Abstract

The utility model provides a liquid nitrogen vaporization system, which is characterized in that redundant equipment is configured for important single equipment (such as a liquid nitrogen storage tank, a supercharging device, a vaporizer, a heater and the like), a controller is additionally arranged, the controller monitors the running state and parameter change of each equipment in real time, and controls each single equipment and each pipeline switching valve through a set automatic control program, so that the liquid nitrogen vaporization system realizes full-automatic switching on, shutdown and safety interlocking protection, when one single equipment fails, the controller can automatically shut down the failed equipment and switch to the redundant equipment, the problem of overall shutdown of the system caused by local failure is avoided, the running stability of the system is enhanced, and the running parameter can be automatically regulated according to the air demand and the pressure of a downstream nitrogen utilization device, so that the system can realize high-efficiency, stable and safe running.

Description

Liquid nitrogen vaporization system

Technical Field

The utility model belongs to the technical field of nitrogen supply, and particularly relates to a liquid nitrogen vaporization system.

Background

The conventional liquid nitrogen vaporization device is usually used as a standby system (public engineering) of an air compression nitrogen system or a matched system of other nitrogen consumption technological processes, and mainly comprises main equipment such as a liquid nitrogen tank, a liquid nitrogen booster pump, a vaporizer, a heater, a buffer tank and the like, pipelines, meters, manual valves and the like.

However, the existing liquid nitrogen vaporizing device has the following problems:

(1) When running, if a single device in the device fails, the whole device is stopped, and the work of downstream nitrogen-using equipment is greatly influenced;

(2) Automatic start-stop and operation parameter adjustment cannot be realized, when different gas consumption and pressure demands exist in the downstream, manual intervention is needed, the demands on site operators are high, and once the site operators are in shortage, the downstream nitrogen utilization equipment is difficult to work.

Disclosure of utility model

Aiming at the problems that the conventional liquid nitrogen vaporization device is out of order to cause the whole shutdown and the parameters cannot be automatically regulated and the like, the utility model provides a liquid nitrogen vaporization system, which is characterized in that redundant equipment is configured for important single equipment such as a liquid nitrogen storage tank, a supercharging device, a vaporizer, a heater and the like, a controller which is respectively and electrically connected with each single equipment, each valve body, a measuring instrument and the like is additionally arranged, the running state and the parameter change of each equipment are monitored in real time, a full-automatic control program is set in the controller, each single equipment, a switching valve and the like can run according to the full-automatic control program, the safety interlocking protection can be realized, when the single equipment is out of order, the problem that the whole system is out of order due to the local failure is automatically switched to the single equipment is avoided, the degree of automation is high, the parameters can be automatically regulated according to requirements, the manual intervention and the field personnel are reduced, and the reliability of the continuous running of the system and the safety and the stability of the air supply are improved.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

A liquid nitrogen vaporization system, comprising: the device comprises a liquid nitrogen supply unit, a vaporization device, a heater, a buffer tank, a nitrogen output pressure regulating device and a controller, wherein the liquid nitrogen supply unit, the vaporization device, the heater, the buffer tank and the nitrogen output pressure regulating device are sequentially connected; the number of the liquid nitrogen supply units is at least 2, and a plurality of the liquid nitrogen supply units are arranged in parallel; the liquid nitrogen supply unit comprises a liquid nitrogen storage tank, a pressurizing device, a liquid nitrogen supply pipeline, a return air pipeline and an overpressure liquid return pipeline; the liquid nitrogen storage tank is provided with a liquid nitrogen outlet, a return air inlet and a return liquid inlet; the pressurizing device is provided with a liquid nitrogen inlet, a first outlet and a second outlet, and the first outlet is connected with the inlet of the vaporizing device; two ends of the liquid nitrogen supply pipeline are respectively connected with the liquid nitrogen outlet and the liquid nitrogen inlet; two ends of the air return pipeline are respectively connected with the second outlet and the air return inlet; one end of the overpressure liquid return pipeline is arranged on a pipeline between the first outlet and the inlet of the vaporizing device, and the other end of the overpressure liquid return pipeline is connected with the liquid return inlet; the nitrogen output pressure regulating device is used for regulating the nitrogen in the buffer tank to the pressure required by downstream nitrogen equipment; the controller is respectively and electrically connected with the pressurizing device, the vaporizing device, the heater and the nitrogen output pressure regulating device, and is used for respectively controlling the opening and closing and opening of the liquid nitrogen inlet, the first outlet and the second outlet, and controlling the starting, stopping and operating parameters of the vaporizing device, the heater and the nitrogen output pressure regulating device.

In some embodiments, the liquid nitrogen supply unit is further provided with a first pressure sensor disposed on a pipeline between the first outlet and the inlet of the vaporizing device, the first pressure sensor being electrically connected with the controller, the first pressure sensor being for detecting a pressure of liquid nitrogen input to the vaporizing device.

In some embodiments, the liquid nitrogen supply unit is further provided with a first pressure regulating valve provided on a line between the first pressure sensor and the inlet of the vaporizing device, the first pressure regulating valve being for controlling the pressure of liquid nitrogen input to the vaporizing device.

In some embodiments, a liquid nitrogen inlet switch valve is arranged on the liquid nitrogen supply pipeline, an air return switch valve is arranged on the air return pipeline, and an overpressure liquid return switch valve is arranged on the overpressure liquid return pipeline; the liquid nitrogen inlet switch valve, the return air switch valve and the overpressure return liquid switch valve are respectively and electrically connected with the controller.

In some embodiments, the liquid supply switching pipelines, the return air switching pipelines and the overpressure return liquid switching pipelines are communicated through the liquid supply switching pipelines, and the liquid supply switching pipelines are provided with liquid supply switching valves; any two return air pipelines are communicated through the return air switching pipeline, and the return air switching pipeline is provided with a return air switching valve; any two overpressure liquid return pipelines are communicated through the overpressure liquid return switching pipeline, and an overpressure liquid return switching valve is arranged on the overpressure liquid return switching pipeline; the liquid supply switching valve, the return air switching valve and the overpressure return liquid switching valve are respectively and electrically connected with the controller.

In some embodiments, a plurality of pressure gauges and a plurality of flow meters are further provided, and the pressure gauges and the flow meters are arranged on the liquid nitrogen storage tank, the buffer tank, the liquid nitrogen supply pipeline, the return gas pipeline, the overpressure return liquid pipeline and the pipeline between the buffer tank and the nitrogen output pressure regulating device; the pressure gauge and the flow meter are respectively and electrically connected with the controller.

In some embodiments, a plurality of temperature sensors are further provided, wherein the temperature sensors are arranged on the liquid nitrogen storage tank, the pressurizing device, the liquid nitrogen supply pipeline, the return gas pipeline, the vaporizing device and the heater; the temperature sensor is electrically connected with the controller.

In some embodiments, the vaporizing device comprises a plurality of vaporizers arranged in parallel, an inlet of the vaporizer being connected to the first outlet, an outlet of the vaporizer being connected to the heater; and a vaporizer switching valve is arranged on a pipeline between the inlet of any vaporizer and the first outlet, and the vaporizer switching valve is electrically connected with the controller.

In some embodiments, the number of the heaters is a plurality, and a plurality of the heaters are arranged in parallel; the number of the buffer tanks is multiple, and a plurality of the buffer tanks are arranged in parallel.

In some embodiments, the vaporizing device is an air temperature vaporizer.

Compared with the prior art, the utility model has the following beneficial effects:

1. According to the liquid nitrogen vaporization system provided by the utility model, redundant equipment is configured for important single equipment (such as a liquid nitrogen storage tank, a supercharging device, a vaporizer, a heater and the like), when one single equipment fails, the controller can automatically shut down the failed equipment and switch to the redundant equipment, so that the problem that the whole system is stopped due to local failure is avoided, and the reliability of continuous operation of the system is enhanced;

2. The liquid nitrogen vaporization system is additionally provided with the controller, the controller is electrically connected with each single device, the pressure gauge, the pipeline switch valve and the like, a full-automatic control program is set in the controller, each single device, the switch valve and the like can operate according to the full-automatic control program, meanwhile, the controller monitors the operation state and parameter change of each device in real time, full-automatic start-up, shutdown and safety interlocking protection are realized, operation is stable, operation parameters can be automatically adjusted according to the air demand and pressure of a downstream nitrogen device, and the single device is automatically switched to redundant device when faults occur, so that the whole operation process of the system is not influenced, the degree of automation is high, and personnel input cost is reduced.

Drawings

The utility model will be further described with reference to the drawings and examples.

FIG. 1 is a schematic diagram of a liquid nitrogen vaporization system according to the present utility model;

fig. 2 is a schematic structural view of a conventional liquid nitrogen vaporizing device in the prior art.

The meaning of the reference symbols in the drawings is as follows:

1-a liquid nitrogen storage tank; 101-a liquid nitrogen outlet; 102-a return air inlet; 103-liquid return inlet;

2-a supercharging device; 201—a liquid nitrogen inlet; 202-a first outlet; 203-a second outlet;

3-a liquid nitrogen supply line; 301-liquid nitrogen inlet switch valve;

4-an air return pipeline; 401-return air switch valve;

5-an overpressure liquid return pipeline; 501-an overpressure liquid return switch valve;

6-a liquid supply switching pipeline; 601-a liquid supply switching valve;

7-an air return switching pipeline; 701-return air switching valve;

8-an overpressure liquid return switching pipeline 801-an overpressure liquid return switching valve;

9-a vaporizer; 901-switching valve of carburetor;

10-a heater;

11-a buffer tank;

12-nitrogen output pressure regulating device;

13-a first pressure sensor; 14-a first pressure regulating valve.

Detailed Description

The present utility model is explained in further detail below with reference to the drawings and the description of specific embodiments, but the following description of the embodiments is included only to enable one of ordinary skill in the art to which the present utility model pertains to more clearly understand the principle and spirit of the present utility model, and is not meant to limit the present utility model in any way.

Fig. 2 shows a conventional liquid nitrogen vaporizing device in the prior art, which comprises a liquid nitrogen storage tank 1, a pressurizing device 2, a vaporizer 9, a heater 10 and a buffer tank 11 which are sequentially connected, wherein liquid nitrogen stored in the liquid nitrogen storage tank 1 flows into the vaporizer 9 after being pressurized by the pressurizing device 2, is vaporized into nitrogen, and then enters the buffer tank 11 for storage after being reheated so as to be supplied to a downstream nitrogen device.

However, in the actual operation process, if one of the devices fails, such as the vaporizer 9 fails, the liquid nitrogen cannot be vaporized, and thus cannot be supplied to the downstream nitrogen device, or the liquid nitrogen storage tank 1 or the pressurizing device 2 fails, so that the whole device is stopped.

In addition, when different gas consumption and pressure are needed by the downstream nitrogen utilization device, the gas consumption pressure and parameters cannot be automatically adjusted by the liquid nitrogen vaporization device, and manual intervention is needed, so that the operation requirement on field personnel is high. In order to solve the defects of the conventional liquid nitrogen vaporizing device, the utility model provides a liquid nitrogen vaporizing system, which comprises the following specific steps:

As shown in fig. 1, the liquid nitrogen vaporization system provided by the present utility model includes: a liquid nitrogen supply unit, a vaporizing device, a heater 10, a buffer tank 11, a nitrogen output pressure regulating device 12 and a controller which are connected in sequence.

The liquid nitrogen supply unit comprises a liquid nitrogen storage tank 1, a pressurizing device 2, a liquid nitrogen supply pipeline 3, a return air pipeline 4 and an overpressure return liquid pipeline 5.

The number of the liquid nitrogen supply units is not limited, at least 2, and a plurality of liquid nitrogen supply units are arranged in parallel. Preferably 2 liquid nitrogen supply units are provided, one for each.

The liquid nitrogen storage tank 1 is provided with a liquid nitrogen outlet 101, a return air inlet 102 and a return liquid inlet 103.

The pressurizing means 2 is provided with a liquid nitrogen inlet 201, a first outlet 202 and a second outlet 203, the first outlet 202 being connected to the inlet of the vaporizing means.

Two ends of the liquid nitrogen supply pipeline 3 are respectively connected with the liquid nitrogen outlet 101 and the liquid nitrogen inlet 201, liquid nitrogen in the liquid nitrogen storage tank 1 flows out from the liquid nitrogen outlet 101, enters the pressurizing device 2 through the liquid nitrogen inlet 201 to be pressurized, and enters the vaporizing device from the first outlet 202 to be vaporized.

Both ends of the return air pipe 4 are connected to the second outlet 203 and the return air inlet 102, respectively.

One end of the overpressure liquid return pipeline 5 is arranged on a pipeline between the first outlet 202 and the inlet of the vaporizing device, and the other end of the overpressure liquid return pipeline 5 is connected with the liquid return inlet 103.

The nitrogen output pressure regulating device 12 is used to regulate the nitrogen in the buffer tank 11 to a pressure required by the downstream nitrogen plant.

More preferably, an outlet flow rate regulating valve is further arranged on the pipeline between the nitrogen output pressure regulating device 12 and the downstream nitrogen device, and the outlet flow rate regulating valve is used for regulating the flow rate of nitrogen input into the downstream nitrogen device.

The basic operation flow of the system is as follows: the liquid nitrogen stored in the liquid nitrogen storage tank 1 is pressurized by the pressurizing device 2 and then enters the vaporizing device, the liquid nitrogen is vaporized into nitrogen, the nitrogen is rewarmed to normal temperature by the heater 10 and then is introduced into the buffer tank 10 for buffering, and then the pressure is regulated to the pressure required by the downstream nitrogen device by the output pressure regulating device 6 and then is output.

The controller is electrically connected with the pressurizing device 2, the vaporizing device, the heater 10 and the nitrogen output pressure regulating device 12 respectively, and is used for controlling the opening and closing and opening of the liquid nitrogen inlet 201, the first outlet 202 and the second outlet 203 respectively and controlling the starting and stopping and operating parameters of the vaporizing device, the heater 10 and the nitrogen output pressure regulating device 12.

The controller is also electrically connected with the outlet flow regulating valve, and can automatically regulate the operation parameters according to the gas demand of the downstream nitrogen utilization device, so that the gas supply can meet the requirement of short-time large-scale or daily average use. When the buffer tank 11 stores high-pressure nitrogen, and the downstream gas consumption is stable, namely, the system operates normally, the opening of the outlet flow regulating valve is relatively fixed, and the system is in daily average steady-state operation; the downstream gas consumption demand increases, and the system can timely supply nitrogen according to the downstream user demand by controlling the opening of the outlet flow regulating valve, so as to increase the nitrogen flow into the downstream nitrogen device, and at this time, the pressure in the buffer tank 11 may be reduced.

In some embodiments, the vaporizing device comprises a plurality of vaporizers 9 arranged in parallel, the inlet of the vaporizer 9 being connected to the first outlet 202, the outlet of the vaporizer 9 being connected to the heater 10.

A vaporizer switching valve 901 is arranged on a pipeline between the inlet of any vaporizer 9 and the first outlet 202, the vaporizer switching valve 901 is electrically connected with the controller, and when one vaporizer 9 fails, the vaporizer switching valve 901 can be switched to other vaporizers 9 for vaporization.

Preferably, the vaporizer 9 may be an air-temperature vaporizer or a water-bath vaporizer, but the heater 10 may be omitted when the water-bath vaporizer is used.

In some embodiments, the number of the heaters 10 may be plural, and the plural heaters 10 are arranged in parallel, and the number of the heaters 10 is preferably 2, and one is used.

The number of the buffer tanks 11 may be plural, and the plurality of buffer tanks 11 are arranged in parallel.

More preferably, the controller comprises a safety interlock module which is electrically connected with the above-mentioned single devices such as the liquid nitrogen storage tank 1, the pressurizing device 2, the vaporizing device, the heater 10 and the like and each switch valve such as the liquid nitrogen inlet switch valve 301 and the like respectively, when abnormal conditions or faults occur in the operation process of the system, the individual or a part of the devices or the switch valves are automatically operated according to set rules and requirements, so that the system is switched into a normal operation or a safe state, for example, when the liquid nitrogen storage tank 1 in one of the liquid nitrogen supply units fails, the liquid nitrogen supply pipeline 3 and the pressurizing device 2 which are communicated with the liquid nitrogen storage tank 1 are immediately stopped, the liquid nitrogen is stopped being supplied, and the liquid nitrogen supply unit connected in parallel with the liquid nitrogen supply unit is started to continue supplying the gas.

In summary, in the liquid nitrogen vaporization system provided by the application, redundant equipment is configured for important single equipment (such as a liquid nitrogen storage device, a pressurizing device, a vaporizer, a heater and the like), when one single equipment fails, the controller can automatically shut down the failed equipment and switch to the redundant equipment, so that the problem of overall shutdown of the system caused by local failure is avoided, and the reliability of continuous operation of the system is enhanced.

In some embodiments, the liquid nitrogen supply pipeline 3 is provided with a liquid nitrogen inlet switch valve 301, the air return pipeline 4 is provided with an air return switch valve 401, the overpressure liquid return pipeline 5 is provided with an overpressure liquid return switch valve 501, and the liquid nitrogen inlet switch valve 301, the air return switch valve 401 and the overpressure liquid return switch valve 501 are respectively electrically connected with a controller.

In some embodiments, the liquid nitrogen supply unit is further provided with a first pressure sensor 13, the first pressure sensor 13 is disposed on a pipeline between the first outlet 202 and the inlet of the vaporizing device, the first pressure sensor 13 is electrically connected with the controller, and the first pressure sensor 13 is used for detecting the pressure of the liquid nitrogen input into the vaporizing device. When the first pressure sensor 13 detects that the pressure on the pipeline between the first outlet 202 and the inlet of the vaporizing device exceeds the set pressure, the controller controls the over-pressure liquid return switch valve 501 to be opened, and the liquid nitrogen in the over-pressure part returns to the liquid nitrogen storage tank 1 through the over-pressure liquid return pipeline 5, so that the pressure fluctuation is timely regulated.

Preferably, the liquid nitrogen supply unit is further provided with a first pressure regulating valve 14, the first pressure regulating valve is arranged on a pipeline between the first pressure sensor 13 and the inlet of the vaporizing device, the first pressure regulating valve 14 is used for controlling or maintaining the pressure of the liquid nitrogen input into the vaporizing device, and when the pressure fluctuation detected by the first pressure sensor 13 is small, the liquid nitrogen input into the vaporizing device can be appropriately pressure-regulated through the first pressure regulating valve 14.

In some embodiments, the controller may be a programmable logic controller PLC, or may take other forms of a processor and its memory, which are not specifically limited herein, and are all within the scope of the present application.

More preferably, the liquid nitrogen vaporization system further comprises a display screen, wherein the display screen is electrically connected with the controller and is used for facilitating setting of various equipment parameters by operators and displaying of the operation condition of the liquid nitrogen vaporization system.

In some embodiments, the liquid nitrogen vaporization system further comprises a plurality of liquid supply switching lines 6, a plurality of return switching lines 7, and a plurality of overpressure return switching lines 8.

Any two liquid nitrogen supply pipelines 3 are communicated through a liquid supply switching pipeline 6, and a liquid supply switching valve 601 is arranged on the liquid supply switching pipeline 6.

Any two return air pipelines 4 are communicated through a return air switching pipeline 7, and the return air switching pipeline 7 is provided with a return air switching valve 701.

Any two overpressure liquid return pipelines 5 are communicated through an overpressure liquid return switching pipeline 8, and an overpressure liquid return switching valve 801 is arranged on the overpressure liquid return switching pipeline 8.

The liquid supply switching valve 601, the return air switching valve 701, and the excess pressure return liquid switching valve 801 are electrically connected to a controller, respectively.

For illustrating the functions of the liquid supply switching pipeline 6, the air return switching pipeline 7 and the overpressure liquid return switching pipeline 8, 2 parallel liquid nitrogen supply units are arranged, wherein one liquid nitrogen supply unit comprises a liquid nitrogen storage tank A, a pressurizing device A, a liquid nitrogen supply pipeline A, an air return pipeline A, an overpressure liquid return pipeline A and a vaporizing device A; the other liquid nitrogen supply unit comprises a liquid nitrogen storage tank B, a pressurizing device B, a liquid nitrogen supply pipeline B, a return air pipeline B, an overpressure return liquid pipeline B and a vaporizing device B, wherein the connection modes of the devices and the pipelines are the same as those shown above, and the detailed description is omitted.

Further, the liquid nitrogen supply pipeline A and the liquid nitrogen supply pipeline B are communicated through a liquid supply switching pipeline C, and a liquid supply switching valve C is arranged on the liquid supply switching pipeline C. When the liquid nitrogen amount in the liquid nitrogen storage tank A is insufficient, the liquid supply switching valve C can be opened, and liquid nitrogen in the other liquid nitrogen storage tank B is used for supplying liquid to the vaporizing device A.

The air return pipeline A is communicated with the air return pipeline B through an air return switching pipeline C, and an air return switching valve C is arranged on the air return switching pipeline C. When the pressure of the liquid nitrogen storage tank A reaches the set storage tank pressure or the liquid nitrogen amount in the liquid nitrogen storage tank A reaches the maximum storage tank capacity, the return air switching valve C can be opened, and the liquid nitrogen needing to be returned to the liquid nitrogen storage tank A is introduced into the other liquid nitrogen storage tank B.

The overpressure liquid return pipeline A and the overpressure liquid return pipeline B are communicated through an overpressure liquid return switching pipeline C, and an overpressure liquid return switching valve C is arranged on the overpressure liquid return switching pipeline C. When overpressure occurs between the first outlet of the pressurizing device A and the inlet of the vaporizing device A, if the pressure of the liquid nitrogen storage tank A reaches the set storage tank pressure or the liquid nitrogen amount in the liquid nitrogen storage tank A reaches the maximum storage tank capacity at the moment, the overpressure liquid return switching valve C can be opened, and liquid nitrogen needing to be returned to the liquid nitrogen storage tank A is introduced into the other liquid nitrogen storage tank B.

In some embodiments, the liquid nitrogen vaporization system is further provided with a plurality of pressure gauges and a plurality of flow meters. Pressure gauges and flow meters are arranged on the liquid nitrogen storage tank 1, the buffer tank 11, the liquid nitrogen supply pipeline 3, the return air pipeline 4, the overpressure return liquid pipeline 5, the liquid supply switching pipeline 6, the return air switching pipeline 7, the overpressure return liquid switching pipeline 8 and pipelines between the buffer tank 11 and the nitrogen output pressure regulating device 12, and the pressure gauges and the flow meters are respectively and electrically connected with the controller.

In some embodiments, the liquid nitrogen vaporization system is provided with a plurality of temperature sensors, and the temperature sensors for detecting temperature are respectively arranged on the liquid nitrogen storage tank 1, the pressurizing device 2, the liquid nitrogen supply pipeline 3, the air return pipeline 4, the vaporization device and the heater 10, and are respectively and electrically connected with the controller.

In some embodiments, the parameters of each device within the liquid nitrogen vaporization system described above are:

(1) The working pressure of the liquid nitrogen storage tank 1 is 0-1MPag, and the storage capacity of the single liquid nitrogen storage tank 1 is required to be configured according to the requirements of users.

(2) The pressurizing device 2 can be a booster pump, the pressure of the liquid nitrogen inlet 201 is 0-1MPag, the rated flow is 1000-20000Nm ³/h (which is required to be configured according to the user requirement), and the first outlet pressure is 1-3MPag (which is required to be configured according to the user requirement).

(3) Vaporizer 9: the operating pressure is 1-3MPag (which is required to be configured according to the requirements of users), the outlet temperature is equal to or higher than the ambient temperature of-20 ℃, and the nitrogen flow is 1000-20000Nm ³/h (which is required to be configured according to the requirements of users).

(4) Heater 10: the operating pressure is 1-3MPag (which is configured according to the user's requirement), and the outlet temperature is normal temperature or configured according to the user's requirement.

(5) Buffer tank 11: the operation pressure is 1-3MPag (which is required to be configured according to the requirement of the user), and the gas storage amount of the buffer tank 11 is required to be configured according to the requirement of the user.

(6) Nitrogen output pressure regulating device 12: the pressure is reduced to the pressure required by the actual downstream, one or more sets of pressure regulating grades can be set, so as to supply air for the downstream low-pressure nitrogen device and the downstream medium-pressure nitrogen device.

The liquid nitrogen supply unit comprises three operation modes, specifically:

(1) Start-up procedure

After the liquid nitrogen storage tank 1 is filled with liquid nitrogen, and parameters such as various pressure, temperature, liquid level and the like are set, an operator clicks a start button on a display, a controller controls a liquid nitrogen inlet switch valve 301 and an air return switch valve 401 to be opened, liquid nitrogen automatically enters the pressurizing device 2 from the liquid nitrogen supply pipeline 3, precooling is performed on the pressurizing device 2 and various pipelines, and then the liquid nitrogen returns to the liquid nitrogen storage tank 1 through the air return pipeline 4.

When the controller judges that the precooling operation is finished through the temperature and the liquid nitrogen storage tank 1 reaches the set pressure, the controller controls the air return switch valve 401 to be closed, the liquid nitrogen supply pipeline 3 continues to convey liquid nitrogen to the pressurizing device 2, meanwhile, the pressurizing device 2 is started to pressurize, and the liquid nitrogen is conveyed to the vaporizing device through the first outlet 202.

The nitrogen obtained by vaporization enters the buffer tank 11 after being heated by the heater 10, when the pressure of the buffer tank 11 reaches a set value, the controller judges that the liquid nitrogen vaporization system is started, the liquid nitrogen vaporization system can enter a normal running state, and then the nitrogen output pressure regulating device 12 is started to supply air to the downstream nitrogen device.

(2) Normal operation process

In the normal operation process, the downstream nitrogen device and each pipeline are respectively provided with a pressure transmitter, the controller can be electrically connected with the pressure transmitters, when the pressure of the air changes, the controller receives the electric signals of the pressure transmitters and converts the electric signals into control signals of the nitrogen output pressure regulating device 12, and the control signals of the nitrogen output pressure regulating device 12 are timely controlled to regulate the pressure of the output nitrogen, so that the requirement of the downstream air consumption is met.

When the gas demand of the downstream nitrogen-using device changes, the controller automatically controls the nitrogen output pressure regulating device 12 and the outlet flow regulating valve to regulate the pressure and flow of the output nitrogen so as to adapt to the downstream gas demand.

The pressure fluctuations generated in the line between the first outlet 202 and the inlet of the vaporizing device can be regulated by opening the overpressure return switching valve 801 and the first pressure regulating valve 14.

The controller can monitor the operation parameters at any time, when a certain single device fails, namely, the interlocking protection is carried out when the interlocking set value in the controller is reached, the cut-in redundant device continues to operate or stops, and automatic operation is realized.

(3) Parking operation procedure

The operator can remotely instruct to click the "park" button on the display, and the running booster device 2 is immediately shut down, the first outlet 202 is closed, and the on-off valves on the respective lines are closed.

The operator can maintain, overhaul and other operations on equipment such as the liquid nitrogen supply unit, the vaporizing device and the like.

In summary, the application adds the controller, and electrically connects the controller with each monomer device, the pressure gauge, the pipeline switch valve, etc., sets the full-automatic control program in the controller, monitors the running state and parameter change of each device in real time, realizes the full-automatic start-up, running and shutdown of the system, can automatically adjust the running parameters of the device according to the air demand and pressure of the downstream nitrogen device, reduces the demands of the conventional liquid nitrogen vaporization device on operators, and simultaneously sets the safety interlocking protection and redundancy device, thereby guaranteeing the running stability of the system.

The preferred embodiments of the present utility model are intended to be illustrative, and various changes and modifications can be made by the person skilled in the art without departing from the scope of the technical spirit of the present utility model.

The technical scope of the present utility model is not limited to the description, but must be determined according to the scope of claims.

Claims (10)

1. A liquid nitrogen vaporization system, comprising:

The device comprises a liquid nitrogen supply unit, a vaporization device, a heater, a buffer tank, a nitrogen output pressure regulating device and a controller, wherein the liquid nitrogen supply unit, the vaporization device, the heater, the buffer tank and the nitrogen output pressure regulating device are sequentially connected;

The number of the liquid nitrogen supply units is at least 2, and a plurality of the liquid nitrogen supply units are arranged in parallel;

the liquid nitrogen supply unit comprises a liquid nitrogen storage tank, a pressurizing device, a liquid nitrogen supply pipeline, a return air pipeline and an overpressure liquid return pipeline;

the liquid nitrogen storage tank is provided with a liquid nitrogen outlet, a return air inlet and a return liquid inlet;

the pressurizing device is provided with a liquid nitrogen inlet, a first outlet and a second outlet, and the first outlet is connected with the inlet of the vaporizing device;

Two ends of the liquid nitrogen supply pipeline are respectively connected with the liquid nitrogen outlet and the liquid nitrogen inlet;

two ends of the air return pipeline are respectively connected with the second outlet and the air return inlet;

One end of the overpressure liquid return pipeline is arranged on a pipeline between the first outlet and the inlet of the vaporizing device, and the other end of the overpressure liquid return pipeline is connected with the liquid return inlet;

The nitrogen output pressure regulating device is used for regulating the nitrogen in the buffer tank to the pressure required by downstream nitrogen equipment;

The controller is respectively and electrically connected with the pressurizing device, the vaporizing device, the heater and the nitrogen output pressure regulating device, and is used for respectively controlling the opening and closing and opening of the liquid nitrogen inlet, the first outlet and the second outlet, and controlling the starting, stopping and operating parameters of the vaporizing device, the heater and the nitrogen output pressure regulating device.

2. A liquid nitrogen vaporization system according to claim 1 wherein,

The liquid nitrogen supply unit is also provided with a first pressure sensor, the first pressure sensor is arranged on a pipeline between the first outlet and the inlet of the vaporizing device, the first pressure sensor is electrically connected with the controller, and the first pressure sensor is used for detecting the pressure of liquid nitrogen input into the vaporizing device.

3. A liquid nitrogen vaporization system according to claim 2 wherein,

The liquid nitrogen supply unit is also provided with a first pressure regulating valve, the first pressure regulating valve is arranged on a pipeline between the first pressure sensor and the inlet of the vaporizing device, and the first pressure regulating valve is used for controlling the pressure of liquid nitrogen input into the vaporizing device.

4. A liquid nitrogen vaporization system according to claim 1 wherein,

The liquid nitrogen supply pipeline is provided with a liquid nitrogen inlet switch valve, the return pipeline is provided with a return air switch valve, and the overpressure liquid return pipeline is provided with an overpressure liquid return switch valve;

The liquid nitrogen inlet switch valve, the return air switch valve and the overpressure return liquid switch valve are respectively and electrically connected with the controller.

5. The liquid nitrogen vaporization system of claim 1, further comprising:

A plurality of liquid supply switching pipelines, a plurality of return air switching pipelines and a plurality of overpressure return liquid switching pipelines,

Any two liquid nitrogen supply pipelines are communicated through the liquid supply switching pipeline, and a liquid supply switching valve is arranged on the liquid supply switching pipeline;

any two return air pipelines are communicated through the return air switching pipeline, and the return air switching pipeline is provided with a return air switching valve;

Any two overpressure liquid return pipelines are communicated through the overpressure liquid return switching pipeline, and an overpressure liquid return switching valve is arranged on the overpressure liquid return switching pipeline;

The liquid supply switching valve, the return air switching valve and the overpressure return liquid switching valve are respectively and electrically connected with the controller.

6. A liquid nitrogen vaporization system according to claim 1 wherein,

A plurality of pressure gauges and a plurality of flow meters are also provided,

The pressure gauge and the flowmeter are arranged on the liquid nitrogen storage tank, the buffer tank, the liquid nitrogen supply pipeline, the return gas pipeline, the overpressure return liquid pipeline and the pipeline between the buffer tank and the nitrogen output pressure regulating device;

the pressure gauge and the flow meter are respectively and electrically connected with the controller.

7. A liquid nitrogen vaporization system according to claim 1 wherein,

The liquid nitrogen storage tank is provided with a plurality of liquid nitrogen supply pipelines, a liquid nitrogen pressurizing device and a liquid nitrogen return pipeline, and the liquid nitrogen supply pipelines are respectively provided with a plurality of temperature sensors;

the temperature sensor is electrically connected with the controller.

8. A liquid nitrogen vaporization system according to claim 1 wherein,

The vaporizing device comprises a plurality of vaporizers which are arranged in parallel, the inlet of the vaporizer is connected with the first outlet, and the outlet of the vaporizer is connected with the heater;

And a vaporizer switching valve is arranged on a pipeline between the inlet of any vaporizer and the first outlet, and the vaporizer switching valve is electrically connected with the controller.

9. A liquid nitrogen vaporization system according to claim 1 wherein,

The number of the heaters is multiple, and the heaters are arranged in parallel;

the number of the buffer tanks is multiple, and a plurality of the buffer tanks are arranged in parallel.

10. The liquid nitrogen vaporization system of claim 7 wherein,

The vaporizing device is an air temperature type vaporizer.