阅读说明：本技术 卸氢系统及其电气控制方法 (Hydrogen discharging system and electrical control method thereof ) 是由 周亮 李明昕 贾艳明 黄景龙 于 2021-08-13 设计创作，主要内容包括：本发明公开了一种卸氢系统及其电气控制方法,包括氢气卸放单元,所述卸放单元包括依次连接的拉断阀、压力表、单向阀、入口截止阀、过滤器、出口截止阀、气动阀；所述卸氢系统还包括氮气吹扫单元、放散单元、仪表风单元及控制单元；所述氢气卸放单元、氮气吹扫单元及放散单元中均设置有气动阀；所述仪表风单元包括三联件,所述三联件通过管路分别于所述气动阀连接,且所述三联件与气动阀之间均设置有电磁阀；所述控制单元包括氢气探测器、火焰探测器、质量流量计、压力变送器、模拟量输入模块和PLC控制器；所述氢气探测器、火焰探测器、质量流量计和模拟量输入模块分别通过线路与PLC控制器电性连接,所述电磁阀和压力变送器分别通过线路与PLC控制器电性连接；以解决现有卸气系统结构功能单一及安全性差的技术问题。(The invention discloses a hydrogen discharge system and an electrical control method thereof, wherein the hydrogen discharge system comprises a hydrogen discharge unit, and the hydrogen discharge unit comprises a breaking valve, a pressure gauge, a one-way valve, an inlet stop valve, a filter, an outlet stop valve and a pneumatic valve which are sequentially connected; the hydrogen unloading system also comprises a nitrogen purging unit, a diffusing unit, an instrument air unit and a control unit; pneumatic valves are arranged in the hydrogen discharging unit, the nitrogen purging unit and the diffusing unit; the instrument wind unit comprises a triple piece, the triple piece is respectively connected with the pneumatic valve through a pipeline, and electromagnetic valves are arranged between the triple piece and the pneumatic valve; the control unit comprises a hydrogen detector, a flame detector, a mass flowmeter, a pressure transmitter, an analog quantity input module and a PLC (programmable logic controller); the hydrogen detector, the flame detector, the mass flow meter and the analog quantity input module are respectively and electrically connected with the PLC through lines, and the electromagnetic valve and the pressure transmitter are respectively and electrically connected with the PLC through lines; the technical problems of single structural function and poor safety of the existing gas unloading system are solved.)

1. A hydrogen discharge system comprises a hydrogen discharge unit, wherein the hydrogen discharge unit comprises a break valve, a pressure gauge, a one-way valve, an inlet stop valve, a filter, an outlet stop valve and a pneumatic valve which are sequentially connected; the system is characterized by further comprising a nitrogen purging unit, a diffusing unit, an instrument air unit and a control unit; pneumatic valves are arranged in the hydrogen discharging unit, the nitrogen purging unit and the diffusing unit; the instrument wind unit comprises a triple piece, the triple piece is respectively connected with the pneumatic valve through a pipeline, and electromagnetic valves are arranged between the triple piece and the pneumatic valve; the control unit comprises a hydrogen detector, a flame detector, a mass flowmeter, a pressure transmitter, an analog quantity input module and a PLC (programmable logic controller); the hydrogen detector, the flame detector, the mass flow meter and the analog quantity input module are respectively electrically connected with the PLC through lines, and the electromagnetic valve and the pressure transmitter are respectively electrically connected with the PLC correspondingly through lines.

2. The hydrogen unloading system as recited in claim 1, wherein the pneumatic valve is connected in parallel with a corresponding bypass branch, and each bypass branch is provided with a corresponding stop valve.

3. The hydrogen offloading system of claim 1, wherein the nitrogen purge unit comprises two pressure transducers.

4. The hydrogen offloading system of claim 1, further comprising a pressure overload protection unit or/and a sampling unit; the pressure overload protection unit is arranged in a main pipeline between the filter and the outlet stop valve, and the sampling unit is arranged in the nitrogen purging unit.

5. The hydrogen discharge system according to claim 4, wherein the pressure overload protection unit includes a safety valve and a check valve, the safety valve has an inlet end communicated with the hydrogen discharge unit through a pipeline and an outlet end communicated with the check valve through a pipeline.

6. The hydrogen unloading system as recited in claim 4, wherein the sampling unit mainly comprises a stop valve and a sampling port connection joint; one end of the stop valve is communicated with the nitrogen purging unit through a pipeline, and the other end of the stop valve is connected with the sampling container through the sampling port connecting joint.

7. A hydrogen discharge system electrical control method implemented based on the hydrogen discharge system of claim 1, comprising the steps of;

s1, the nitrogen purging unit is connected with a nitrogen source pipeline, the diffusing port unit is communicated with a centralized diffusing pipeline, the instrument air inlet is communicated with an instrument air source pipeline, the hydrogen inlet of the unloading hose is communicated with a tube bundle vehicle or a corresponding equipment outlet, and the hydrogen discharging main path outlet is connected with a sequence disc, so that the electromagnetic valve in the hydrogen discharging main path and the stop valves on the bypass branches thereof are ensured to be in a closed state;

s2, inputting a nitrogen purging signal, and when the pressure transmitter monitors that the pipeline pressure is less than 0.2MPa, controlling the nitrogen purging unit, the electromagnetic valves of the diffusing unit and the pneumatic valve to be opened in sequence by the PLC, discharging nitrogen after flowing through each pipeline, and closing the electromagnetic valves and the pneumatic valve;

s3, repeating the operation of S2 for three times to complete the nitrogen purging before hydrogen unloading;

s4, opening the inlet stop valve and the outlet stop valve in sequence, inputting a hydrogen discharge command signal, and controlling the opening of an electromagnetic valve and a pneumatic valve in the hydrogen discharge main circuit by the PLC controller to conduct the hydrogen discharge main circuit and start gas discharge;

s5, after hydrogen discharge is completed, closing the pneumatic valve on the hydrogen discharge main path, and stopping hydrogen discharge;

s6, inputting a nitrogen purging signal, when the pressure in the pressure transmitter monitoring pipeline is larger than or equal to 0.2MPa, opening a pneumatic valve in the diffusing unit, discharging high-pressure hydrogen in the pipe into the concentrated diffusing pipeline, when the pressure in the pressure transmitter monitoring pipeline is smaller than or equal to 0.2MPa, closing the pneumatic valve in the diffusing unit, opening the pneumatic valve in the nitrogen purging unit, and allowing nitrogen to enter the pipeline;

s7, when the pressure of the nitrogen in the pipeline reaches a set value, a pneumatic valve in the diffusing unit is opened, and the nitrogen in the pipeline enters the centralized diffusing pipeline;

s8, closing a pneumatic valve in the nitrogen purging unit, and when the pressure of nitrogen in the monitoring pipe of the pressure transmitter is less than or equal to 0.1MPa, closing the pneumatic valve in the diffusing unit and stopping purging the nitrogen;

s9, repeating the steps S6-S8 for three times, and finishing nitrogen purging after hydrogen unloading;

and S10, closing the inlet stop valve and the outlet stop valve in sequence to finish one-time gas unloading operation.

Technical Field

The invention relates to the technical field of new energy equipment, in particular to a hydrogen unloading system and an electrical control method thereof.

Background

China is a large industrial country and is also the country with the most reserved quantity of global motor vehicles, and a large amount of greenhouse gas generated in industrial production and transportation is not beneficial to the goal of reducing carbon emission promised by China to the world, so the development of the countries on clean energy is more and more important in recent years. With the development of science and technology, the emergence of hydrogen fuel cell automobiles is beneficial to the national fundamental reduction of continuously increased carbon emission. The core power of a hydrogen fuel cell automobile is a hydrogen fuel cell, which is a power generation device that directly converts chemical energy of hydrogen and oxygen in the air into electric energy.

At present, hydrogen required by a hydrogen fuel cell automobile is mainly obtained from a hydrogen filling station, hydrogen in the main hydrogen filling station is provided by an external hydrogen supply tube bundle trailer, and the hydrogen in the tube bundle trailer is discharged to a compressor or a pressure container in the hydrogen filling station to provide high-pressure hydrogen for a downstream hydrogenation machine. However, in the process of connecting the tube bundle trailer with the compressor or the pressure vessel, the hydrogen conveying pipelines composed of a plurality of simple components such as a connecting hose, a high-pressure pipeline, a safety valve and a ball valve are mostly connected, and the structural function units are mostly caused because the hydrogen filling station belongs to a new energy source station and few built-up hydrogen filling stations in China. But in this in-process but have hydrogen leakage or have under the condition of the unknown fire source unable monitoring and warning shut down, the mass flow that can't count hydrogen and carry, unable in time prevent the unidentified impurity that exists in the air supply, can't carry out hydrogen sampling analysis, can't avoid the long tube trailer when unexpected swift current car breaks connecting hose to and can't carry out pipeline sweep and medium replacement when the pipeline overhauls and maintains.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is known to a person skilled in the art.

Disclosure of Invention

The invention aims to provide a hydrogen unloading system and an electrical control method thereof, and aims to solve the technical problems of single structural function and low safety of the conventional gas unloading system.

In order to solve the technical problems, the invention adopts the following technical scheme:

the hydrogen discharging unit comprises a breaking valve, a pressure gauge, a one-way valve, an inlet stop valve, a filter, an outlet stop valve and a pneumatic valve which are connected in sequence; the hydrogen unloading system also comprises a nitrogen purging unit, a diffusing unit, an instrument air unit and a control unit; pneumatic valves are arranged in the hydrogen discharging unit, the nitrogen purging unit and the diffusing unit; the instrument wind unit comprises a triple piece, the triple piece is respectively connected with the pneumatic valve through a pipeline, and electromagnetic valves are arranged between the triple piece and the pneumatic valve; the control unit comprises a hydrogen detector, a flame detector, a mass flowmeter, a pressure transmitter, an analog quantity input module and a PLC (programmable logic controller); the hydrogen detector, the flame detector, the mass flow meter and the analog quantity input module are respectively electrically connected with the PLC through lines, and the electromagnetic valve and the pressure transmitter are respectively electrically connected with the PLC through lines.

Preferably, the pneumatic valve is provided with corresponding bypass branches in parallel, and each bypass branch is provided with a corresponding stop valve.

Preferably, the nitrogen purge unit contains two pressure transmitters.

Preferably, the hydrogen unloading system further comprises a pressure overload protection unit or/and a sampling unit; the pressure overload protection unit is arranged in a main pipeline between the filter and an outlet stop valve, and the sampling unit is arranged in the nitrogen purging unit.

Preferably, the pressure overload protection unit includes a safety valve and a check valve, an inlet end of the safety valve is connected to the main hydrogen discharge path through a pipeline, and an outlet end of the safety valve is connected to the check valve through a pipeline.

Preferably, the sampling unit mainly comprises a stop valve and a sampling port connecting joint; one end of the stop valve is communicated with the nitrogen purging unit through a pipeline, and the other end of the stop valve is connected with the sampling container through the sampling port connecting joint.

An electrical control method of a hydrogen unloading system of a hydrogen refueling station is implemented based on the hydrogen unloading system and comprises the following steps:

s1, the nitrogen purging unit is connected with a nitrogen source pipeline, the diffusing port unit is communicated with a centralized diffusing pipeline, the instrument air inlet is communicated with an instrument air source pipeline, the hydrogen inlet of the unloading hose is communicated with a tube bundle vehicle or a corresponding equipment outlet, and the hydrogen unloading main pipeline outlet is connected with a sequence disk to ensure that the electromagnetic valve on the hydrogen unloading main pipeline and the stop valves on the bypass branches thereof are in a closed state;

s2, inputting a nitrogen purging signal, when the pressure transmitter monitors that the pipeline pressure is less than 0.2MPa, sequentially opening pneumatic valves in the nitrogen purging unit and the diffusing unit, discharging nitrogen after flowing through each pipeline, and closing the pneumatic valves;

s3, repeating the operation of S2 for three times to complete the nitrogen purging before hydrogen unloading;

s4, opening the inlet stop valve and the outlet stop valve in sequence, inputting a hydrogen discharge command signal, opening a pneumatic valve on the hydrogen discharge main path, conducting the hydrogen discharge main path and starting to discharge gas;

s5, after hydrogen discharge is completed, closing the pneumatic valve on the hydrogen discharge main path, and stopping hydrogen discharge;

s6, inputting a nitrogen purging signal, when the pressure in the pressure transmitter monitoring pipeline is larger than or equal to 0.2MPa, opening a pneumatic valve in the diffusing unit, discharging high-pressure hydrogen in the pipe into the concentrated diffusing pipeline, when the pressure in the pressure transmitter monitoring pipeline is smaller than or equal to 0.2MPa, closing the pneumatic valve in the diffusing unit, opening the pneumatic valve in the nitrogen purging unit, and allowing nitrogen to enter the pipeline;

s7, when the pressure of the nitrogen in the pipeline reaches a set value, a pneumatic valve in the diffusing unit is opened, and the nitrogen in the pipeline enters the centralized diffusing pipeline;

s8, closing a pneumatic valve in the nitrogen purging unit, and when the pressure of nitrogen in the monitoring pipe of the pressure transmitter is less than or equal to 0.1MPa, closing the pneumatic valve in the diffusing unit and stopping purging the nitrogen;

s9, repeating the steps S6-S8 for three times to complete the nitrogen purging work after hydrogen unloading;

and S10, closing the inlet stop valve and the outlet stop valve in sequence to finish one-time gas unloading operation.

Compared with the prior art, the invention has the main beneficial technical effects that:

1. the system has reasonable structural design, integrates multiple functions while ensuring convenient operation, has high automation degree, and not only can be used as the gas unloading equipment of the tube bundle trailer, but also can be used as the filling equipment to directly perform filling service on downstream equipment.

2. The invention has strong safety protection function, and multiple monitoring and protection are carried out on the safety of the system in real time through the arranged hydrogen concentration detector, the pressure overload safety valve and the like.

Drawings

FIG. 1 is a gas path schematic diagram of the hydrogen discharge system of the present invention.

FIG. 2 is a schematic view of the piping structure of the hydrogen discharge system of the present invention.

Fig. 3 is an electrical control schematic of the present invention.

FIG. 4 is a flow chart of the air discharge logic control of the present invention.

FIG. 5 is a flow chart of the automatic purge logic control of the present invention.

In the above drawings, 1 is a hydrogen gas discharging unit 1, 11 is a breaking valve, 12 is a pressure gauge, 13 is a first check valve, 14 is an inlet check valve, 15 is a filter, 16 is a flow meter, 17 is an outlet check valve, 18 is a first pneumatic valve, 2 is a nitrogen gas purging unit, 21 is a second pneumatic valve, 22 is a second check valve, 23 is a pressure transmitter, 3 is a bleeding unit, 31 is a third pneumatic valve, 32 is a third check valve, 4 is a pressure overload protection unit, 41 is a safety valve, 5 is a sampling unit, 51 is a manual check valve, 52 is a sampling connection joint, 6 is an instrument air inlet, 7 is a pneumatic triple piece, 8 is an electromagnetic valve, 81 is a first electromagnetic valve, 82 is a second electromagnetic valve, and 83 is a third electromagnetic valve.

Detailed Description

The following examples are intended to illustrate the present invention in detail and should not be construed as limiting the scope of the present invention in any way.

In the description of the technical solutions of the present invention, it should be understood that the orientations or positional relationships indicated as referring to the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Reference herein to "first," "second," etc., is used to distinguish between similar items and not to limit the particular order or sequence.

Example 1: a hydrogen unloading system, referring to fig. 1 to 5, comprises a hydrogen unloading unit 1, a nitrogen purging unit 2, a diffusing unit 3, a pressure overload protection unit 4 and a sampling unit 5, wherein all the units are sequentially communicated with the hydrogen unloading unit 1 through pipelines.

The hydrogen discharging unit 1 is sequentially connected with a breaking valve 11, a pressure gauge 12, a first one-way valve 13, an inlet stop valve 14, a filter 15, a flowmeter 16, an outlet stop valve 17 and a first pneumatic valve 18 from a hydrogen inlet to a hydrogen outlet; the snapping valve 11 is arranged between the hydrogen unloading inlet and the gas unloading equipment, a bidirectional check valve is arranged in the snapping valve, once the filling gun is pulled by a certain external force, the snapping valve 11 can be automatically broken, and meanwhile, a pipeline is automatically closed and cut off, so that dangerous accidents are avoided; the first check valve 13 prevents the high-pressure gas (hydrogen/nitrogen) from reversely flowing and conducting during working, and prevents dangerous situations such as leakage of a large amount of hydrogen; the pressure gauge 12 is a high-precision oil-forbidden pressure gauge, the measuring range is 0-100MPa, the precision grade is plus or minus 0.1%, the filter 15 blocks particle impurities and dirt mixed in hydrogen, and discharges clean hydrogen, so that clean hydrogen is provided for the hydrogen energy valve comprehensive testing device, and normal work and operation of pipe valves of a pipeline system are protected; the flow meter 16 can realize the real-time acquisition, processing and calculation of parameter information of hydrogen, such as flow, temperature, density and the like, so as to obtain the mass of hydrogen flowing through the flow meter 16; the first pneumatic valve 18 is a switching action of a double-acting cylinder, is driven to be executed by an execution air source, and is correspondingly matched with a first electromagnetic valve to control the opening and closing of the valve.

The nitrogen purging unit 2 is arranged on the hydrogen discharging unit 1 between the snapping valve 11 and the first check valve 13 and comprises a second pneumatic valve 21, a second check valve 22 and two pressure transmitters 23, preferably, the two pressure transmitters 23 are arranged to ensure that when one pressure transmitter 23 fails, the other pressure transmitter can quickly replace the function of the other pressure transmitter, and the whole hydrogen discharging process cannot be influenced.

The bleeding unit 3 is provided on the hydrogen discharging unit 1 between the first check valve 13 and the inlet shutoff valve 14, and includes a third air-operated valve 31 and a third check valve 32.

The pressure overload protection unit 4 is arranged on the hydrogen discharge unit 1 between the filter 15 and the outlet stop valve 17, and mainly comprises a safety valve 41, the safety valve 41 is communicated with the main hydrogen discharge path through a pipeline inlet end, an outlet end is communicated with the third one-way valve 31 through a pipeline, pressure is released through a discharge port of the discharge unit 3, when the pressure of hydrogen in the hydrogen discharge unit 1 is greater than or equal to a pressure value set by the safety valve, the valve of the safety valve 41 is automatically opened, high-pressure gas in the pipeline is discharged to a centralized discharge pipeline through the third one-way valve 31, and when the pressure in the hydrogen discharge unit 1 is less than the pressure value set by the safety valve 41, the valve of the safety valve 41 is automatically closed.

The sampling unit 5 is arranged on the nitrogen purging unit 2 and the hydrogen discharging unit 1 communicating pipeline, and comprises a manual stop valve 51 and a sampling connecting joint 52, when the hydrogen discharging unit 1 is filled with high-pressure hydrogen, the manual stop valve is opened, the hydrogen enters a sampling container connected with the sampling connecting joint 52 through the sampling unit 5, and after sampling is completed, the manual stop valve 51 is closed.

The pipeline connecting parts of the first pneumatic valve 18, the second pneumatic valve 21 and the third pneumatic valve 31 are provided with bypass branches, the bypass branches are provided with manual stop valves, and the manual stop valves are manually opened or closed to ensure the normal operation of the hydrogen unloading process in the state that the pneumatic valves cannot normally work.

The hydrogen unloads the gas pipeline and still includes instrument wind import 6, pneumatic trigeminy piece 7, main line break-make button SB101, nitrogen gas purge button SB102 and scram button, pneumatic trigeminy piece 7 fixed connection be in instrument wind import 6 departments, pneumatic trigeminy piece 7 through the pipeline respectively with first pneumatic valve 18, second pneumatic valve 21, third pneumatic valve 31 switch on, just be provided with first solenoid valve 81 in pneumatic trigeminy piece 7 and the first pneumatic valve 18 intercommunication pipeline, with be provided with second solenoid valve 82 in the second pneumatic valve 21 intercommunication pipeline, with be provided with third solenoid valve 83 in the third pneumatic valve 31 intercommunication pipeline, solenoid valve 8 is used for controlling the break-make of instrument wind execution pipeline to control pneumatic valve's opening and close, pneumatic trigeminy piece 7 provides the clean nitrogen gas source of execution pipeline respectively for the pneumatic valve. Pressing the main path on-off button opens the valve of the first pneumatic valve 18, and pressing the main path on-off button closes the valve of the first pneumatic valve 18; pressing the nitrogen purging key SB102, starting nitrogen purging, and pressing the nitrogen purging key SB102 again to finish nitrogen purging; when the emergency stop button is pressed, the first solenoid valve 81, the second solenoid valve 82, and the third solenoid valve 83 are simultaneously de-energized, thereby controlling the first, second, and third air-operated valves 18, 21, and 31 to be closed.

The hydrogen detector can realize the rapid, accurate and real-time monitoring of the concentration of combustible gas, particularly hydrogen; the hydrogen unloading system is also provided with an emergency stop button, the emergency stop button is pressed down to simultaneously power off the first electromagnetic valve, the second electromagnetic valve and the third electromagnetic valve, so that the first pneumatic valve, the second pneumatic valve and the third pneumatic valve are controlled to be closed emergently, once the flame detector monitors fire information, the emergency stop button is immediately started, and the safety protection function of the hydrogen unloading station is realized.

Example 2: an electrical control method of a hydrogen discharge system is implemented based on the hydrogen discharge system in embodiment 1, the PLC controller receives and processes relevant information collected by the hydrogen detector, the flame detector, the pressure transmitter, and/or the mass flow meter through the analog input module, and controls the opening and closing of corresponding electromagnetic valves in the hydrogen discharge main path, the nitrogen purge branch path, and the bleeding branch path according to a set value or an input instruction, and the specific flow is as follows:

s1, connecting the hydrogen inlet of the unloading hose with the outlet of the tube bundle vehicle or other equipment, and connecting the hydrogen outlet with the inlet of the sequence control panel or other equipment; the outlet of the nitrogen source pipeline is connected with the nitrogen purging inlet; the diffusing port is connected with a centralized diffusing pipeline; the outlet of the instrument wind air source pipeline is connected with the inlet of the instrument wind, so that the valves of the first pneumatic valve 18 and the bypass branch manual stop valve are all in a closed state.

S2, the nitrogen purging button SB102 is pressed, the nitrogen automatic purging replacement function is started, when the pressure transmitter 23 monitors that the gas pressure in the pipeline is less than 0.2MPa, the second electromagnetic valve 82 is electrified, and the instrument wind and gas source enters the second pneumatic valve 21 through the pneumatic triple 7. The second pneumatic valve is opened, nitrogen flows through the second one-way valve 22 to enter the hydrogen discharge unit 1, and then passes through the snapping valve 11 and the hydrogen inlet of the unloading hose; after the second electromagnetic valve 82 is electrified for 5 seconds, the third electromagnetic valve 83 is electrified, the instrument air source passes through the pneumatic triple piece 7 and enters the pneumatic actuating mechanism of the third pneumatic valve 31, the valve of the third pneumatic valve 31 is opened, nitrogen flows through the hydrogen discharging unit 1 and the third one-way valve 32 and is discharged into the centralized diffusion pipeline system, at the moment, the nitrogen flows to the hydrogen inlet simultaneously, flows in the direction of the diffusion port and is discharged, when the electrifying time of the second electromagnetic valve 82 and the third electromagnetic valve 83 is equal to the set time, the second electromagnetic valve and the third electromagnetic valve are powered off, the second electromagnetic valve and the third pneumatic valve are closed, and the system stops nitrogen purging.

And S3, repeating the operation of S2 three times, namely, completing the nitrogen purging replacement operation of the air in the pipeline before the whole gas unloading.

S4, hydrogen enters the inlet end of the hydrogen discharge unit 1 from the discharge outlet, and passes through the breaking valve 11, the pressure gauge 12 (the pressure gauge measures and displays the pressure value of the main pipeline in real time), the pressure transmitter 23 (the pressure transmitters PT101 and PT102 collect the pressure data of the main pipeline in real time and transmit the data to the background PLC control system, so that the pressure of the main pipeline can be monitored, recorded and fed back in real time), the first check valve 13 and the flow-to-inlet stop valve 14 are opened manually in sequence, the hydrogen flows through the inlet stop valve 14, the filter 15, the flowmeter 16 and the outlet stop valve 17 to the first pneumatic valve 18, the main pipeline on-off button SB101 is pressed, the first solenoid valve 81 is powered on, the instrument wind gas source flows through the pneumatic triple 7 to enter the pneumatic actuator of the first pneumatic valve 18, the valve of the first pneumatic valve 18 is opened, so that the hydrogen in the main pipeline is discharged out of the discharge system pipeline, and (4) flowing into the next hydrogenation equipment, and starting gas discharge.

S5, the main pipeline on-off button SB101 is pressed, the first electromagnetic valve 81 is powered off, the first pneumatic valve 18 is closed, and air discharge is stopped.

S6, press nitrogen sweep button SB102, the automatic replacement function that sweeps of nitrogen is opened, pressure transmitter 23 monitors when gas pressure is not less than 0.2MPa in the pipeline, third solenoid valve 83 circular telegram, instrument wind gas source flows through pneumatic trigeminy piece 7, gets into the pneumatic actuating mechanism of third pneumatic valve 31, the valve of third pneumatic valve 31 is opened, and high-pressure hydrogen discharges into concentrated diffuse pipe-line system through third check valve 32 in the pipeline, and when high-pressure hydrogen pressure is not more than 0.2MPa in the pipeline, third solenoid valve 83 is automatic outage, the valve of third pneumatic valve 31 is closed, and high-pressure hydrogen stops diffusing in the pipeline, and second solenoid valve 82 circular telegram, instrument wind gas source process pneumatic trigeminy piece 7, gets into the pneumatic actuating mechanism of second pneumatic valve 21, and the valve of second pneumatic valve 21 is opened, and nitrogen flow through second check valve 22 gets into the main pipeline.

And S7, when the pressure of the nitrogen in the pipeline is equal to 0.8MPa, the third electromagnetic valve 83 is electrified, and the instrument wind and gas source enters the third pneumatic valve 31 through the pneumatic triple piece 7. The third pneumatic valve 31 is opened and nitrogen flows through the third one-way valve 32, the diffusing port and into the centralized diffusing pipeline system.

And S8, when the electrifying time of the second electromagnetic valve 82 is equal to the set time (10S), the second electromagnetic valve 82 is powered off, the second air-operated valve 21 is closed, the system stops nitrogen purging, when the pressure of nitrogen in the pipeline is not more than 0.1MPa, the third electromagnetic valve 83 is powered off, the third air-operated valve 31 is closed, and the system stops nitrogen purging.

And S9, repeating the operations S6-S8 three times, namely finishing the nitrogen purging work after hydrogen unloading.

And S10, manually closing the inlet stop valve 14 and the outlet stop valve 17 in sequence, correctly detaching the hydrogen inlet end joint of the unloading hose communicated with the tube bundle vehicle, and completing the sequential gas unloading operation after the unloading hose is placed in the original position.

While the invention has been described in detail with reference to the drawings and examples, it will be understood by those skilled in the art that various changes in the details of the embodiments may be made without departing from the spirit of the invention, and various changes in the details of construction and materials may be substituted for elements thereof to form various embodiments, which are within the scope of the invention and are not intended to be limited to the details of the embodiments.