An automatic hydrogen-nitrogen mixing system

Abstract

This utility model relates to an automatic hydrogen-nitrogen mixing system, belonging to the field of gas mixing technology. The system includes a hydrogen pressure stabilizing tank, a nitrogen pressure stabilizing tank, and a mixed gas pressure stabilizing tank. The hydrogen pressure stabilizing tank has a hydrogen outlet pipe, the nitrogen pressure stabilizing tank has a nitrogen outlet pipe, and the mixed gas pressure stabilizing tank has a mixed gas inlet pipe. Both the hydrogen and nitrogen outlet pipes are connected to the mixed gas inlet pipe. A gas mass flow control valve is installed on the hydrogen outlet pipe, and a gas flow meter is installed on the nitrogen outlet pipe. The system also includes a PLC controller, with the gas flow meter and the gas mass flow control valve electrically connected to the PLC controller. This utility model avoids the drawbacks of using PID control methods, such as complex parameter settings, potential overshoot due to integral operation, sensitivity to noise in derivative operation, and slow dynamic response.

Description

Technical Field

[0001] This utility model relates to the field of gas mixing technology, and in particular to an automatic nitrogen-hydrogen mixing system. Background Technology

[0002] Utility model patent application No. 2019109031648 discloses an intelligent automatic hydrogen-nitrogen mixing device. The device includes a hydrogen pressure stabilizing tank, a nitrogen pressure stabilizing tank, and a mixing tank. The mixing tank is equipped with a gas mixing pipeline. The nitrogen pressure stabilizing tank is connected to the gas mixing pipeline via a nitrogen supply pipeline, and the hydrogen pressure stabilizing tank is connected to the gas mixing pipeline via a hydrogen supply pipeline. The nitrogen supply pipeline is equipped with a first pressure gauge, a first pneumatic valve, and a first shut-off valve in sequence according to the order in which nitrogen gas passes through. The hydrogen supply pipeline is equipped with a second shut-off valve, a second pneumatic valve, a regulating valve, and a third shut-off valve in sequence according to the order in which hydrogen gas passes through. The system includes a stop valve; a hydrogen supply branch pipe connects the input end of the second stop valve to the output end of the third stop valve, and a second pressure gauge and a bypass valve are sequentially installed on the hydrogen supply branch pipe according to the order in which hydrogen passes through; a mixed gas detection pipeline is connected to the gas mixing pipeline, which includes a hydrogen analyzer connected via a delivery pipe; the hydrogen analyzer is connected to a PID controller, which is connected to a regulating valve on the hydrogen supply pipeline; the mixing tank is equipped with an outlet pipe, and a vent valve and a mixed gas discharge valve are installed in parallel at the outer end of the outlet pipe; a flow meter is installed on the outlet pipe. The PID controller collects real-time data from the hydrogen analyzer and controls the regulating valve on the hydrogen supply pipeline based on the real-time data collected by the PID controller to increase or decrease the hydrogen flow rate, thereby effectively controlling the hydrogen concentration in the nitrogen gas and maintaining it at the required concentration.

[0003] As can be seen from the above, this automatic hydrogen-nitrogen mixing device uses the traditional PID control method, which requires real-time adjustment of the hydrogen flow rate based on the hydrogen content in the mixed gas analyzed by the hydrogen analyzer. In other words, it controls the front-end input by monitoring the back-end results, which is a reactive control method. While the PID control method can meet the accuracy requirements of gas mixing, it suffers from drawbacks such as complex parameter settings, potential overshoot due to integral operation, sensitivity to noise in derivative operation, and slow dynamic response. Utility Model Content

[0004] The present invention aims to improve the shortcomings of the above-mentioned automatic hydrogen-nitrogen mixing device.

[0005] Therefore, the present invention adopts the following technical solution:

[0006] An automatic hydrogen-nitrogen mixing system includes a hydrogen pressure stabilizing tank, a nitrogen pressure stabilizing tank, and a mixed gas pressure stabilizing tank. The hydrogen pressure stabilizing tank is equipped with a hydrogen outlet pipe, the nitrogen pressure stabilizing tank is equipped with a nitrogen outlet pipe, and the mixed gas pressure stabilizing tank is equipped with a mixed gas inlet pipe. Both the hydrogen outlet pipe and the nitrogen outlet pipe are connected to the mixed gas inlet pipe. A gas mass flow control valve is installed on the hydrogen outlet pipe, and a gas flow meter is installed on the nitrogen outlet pipe. The system also includes a PLC controller, and the gas flow meter and the gas mass flow control valve are electrically connected to the PLC controller.

[0007] This invention employs a "nitrogen flow rate-based quantitative hydrogen method," which controls hydrogen input based on nitrogen input, thus constituting in-transit control. Since this invention does not use PID control, the control process does not rely on a hydrogen content analyzer to collect hydrogen content data in the mixture, and is independent of the integral and derivative functions synthesized. This avoids the drawbacks of PID control, such as complex parameter settings, potential overshoot due to integral operation, sensitivity to noise in derivative operation, and slow dynamic response. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the overall structure of this utility model. Detailed Implementation

[0009] To better understand this utility model, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments.

[0010] like Figure 1 An automatic hydrogen-nitrogen mixing system is shown, comprising a hydrogen pressure stabilizing tank 1, a nitrogen pressure stabilizing tank 2, and a mixed gas pressure stabilizing tank 3. The hydrogen pressure stabilizing tank 1 is equipped with a hydrogen pressure gauge 1.1, a hydrogen pressure relief valve 1.2, a hydrogen inlet pipe 1.3, and a hydrogen outlet pipe 1.4. The nitrogen pressure stabilizing tank 2 is equipped with a nitrogen pressure gauge 2.1, a nitrogen pressure relief valve 2.2, a nitrogen inlet pipe 2.3, and a nitrogen outlet pipe 2.4. The mixed gas pressure stabilizing tank 3 is equipped with a mixed gas pressure gauge 3.1, a mixed gas pressure relief valve 3.2, a mixed gas inlet pipe 3.3, and a mixed gas outlet pipe 3.4. Outlet pipe 3.4; Hydrogen inlet pipe 1.3 is used to connect to the hydrogen source, nitrogen inlet pipe 2.3 is used to connect to the nitrogen source, hydrogen outlet pipe 1.4 and nitrogen outlet pipe 2.4 are both connected to the mixed gas inlet pipe 3.3, and mixed gas outlet pipe 3.4 is used to connect to the gas consumption end; hydrogen outlet pipe 1.4 is equipped with a hydrogen manual shut-off valve 1.5 and a gas mass flow control valve 1.6, nitrogen outlet pipe 2.4 is equipped with a nitrogen manual outlet valve 2.5 and a gas flow meter 2.6, and mixed gas outlet pipe 3.4 is equipped with a mixed gas manual outlet valve 3.5.

[0011] like Figure 1As shown, the automatic hydrogen-nitrogen mixing system also includes a PLC controller 4, a gas flow meter 2.6 which is electrically connected to the input terminal of the PLC controller 4 as a data acquisition device, and a gas mass flow control valve 1.6 which is electrically connected to the output terminal of the PLC controller 4 as an actuator. During operation, the gas flow meter 2.6 can monitor the nitrogen flow in real time, and the PLC controller 4 can control the gas mass flow control valve 1.6 in real time according to the nitrogen flow to adjust the hydrogen flow, thereby realizing the automatic proportioning of hydrogen and nitrogen in the mixed gas.

[0012] like Figure 1 As shown, hydrogen gas enters hydrogen pressure stabilizing tank 1 through hydrogen inlet pipe 1.3 for storage. The pressure inside hydrogen pressure stabilizing tank 1 is monitored in real time by hydrogen pressure gauge 1.1. If the pressure exceeds the set value, the pressure in hydrogen pressure stabilizing tank 1 can be adjusted to the set value by hydrogen pressure relief valve 1.2. Nitrogen gas enters nitrogen pressure stabilizing tank 2 through nitrogen inlet pipe 2.3 for storage. The pressure inside nitrogen pressure stabilizing tank 2 is monitored in real time by nitrogen pressure gauge 2.1. If the pressure exceeds the set value, the pressure in hydrogen pressure stabilizing tank 2 can be adjusted to the set value by nitrogen pressure relief valve 2.2. It should be noted that in order to ensure a stable hydrogen and nitrogen ratio and to ensure the mixed gas flows in the predetermined direction, the pressure setting of hydrogen pressure stabilizing tank 1 must be less than the outlet pressure of the hydrogen source, the pressure setting of nitrogen pressure stabilizing tank 2 must also be less than the outlet pressure of the hydrogen source, the pressure setting of hydrogen pressure stabilizing tank 1 must be greater than the pressure setting of nitrogen pressure stabilizing tank 2 (the greater the pressure difference between the two, the more stable the ratio), and the pressure setting of mixed gas pressure stabilizing tank 3 must be equal to the pressure setting of nitrogen pressure stabilizing tank 2 and greater than the inlet pressure of the gas consumption end. After the pressure in hydrogen pressure tank 1 and nitrogen pressure tank 2 is adjusted to the correct levels, open the manual hydrogen valve 1.5 and the manual nitrogen valve 2.5. Hydrogen flows along the hydrogen outlet pipe 1.4 and nitrogen flows along the nitrogen outlet pipe 2.4 into the mixed gas inlet pipe 3.3 for premixing, and then enters the mixed gas pressure tank 3 for storage. The pressure in the mixed gas pressure tank 3 is monitored in real time by the mixed gas pressure gauge 3.1 until the pressure in the mixed gas pressure tank 3 matches that in the nitrogen pressure tank 2. If there is overpressure, the pressure in the mixed gas pressure tank 3 can be adjusted to the set value by the mixed gas pressure relief valve 3.2. After uniform mixing, the manual mixed gas valve 3.5 can be opened, and the mixed gas flows out from the mixed gas outlet pipe 3.4 for use by the gas user. To achieve the above pressure control, hydrogen pressure gauge 1.1, nitrogen pressure gauge 2.1 and mixed gas pressure gauge 3.1 can all be electrically connected to the input terminal of PLC controller 4 as data acquisition devices, and hydrogen pressure relief valve 1.2, nitrogen pressure relief valve 2.2 and mixed gas pressure relief valve 3.2 can all be electrically connected to PLC controller 4 as actuators.

[0013] like Figure 1 As shown, in order to ensure that hydrogen and nitrogen are fully mixed before entering the mixed gas pressure stabilizing tank 3, a gas stirrer 5 can be connected in series on the mixed gas inlet pipe 3.3.

[0014] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An automatic proportioning hydrogen-nitrogen gas mixing system, comprising a hydrogen pressure stabilizing tank, a nitrogen pressure stabilizing tank and a mixed gas pressure stabilizing tank, the hydrogen pressure stabilizing tank being provided with a hydrogen outlet pipe, the nitrogen pressure stabilizing tank being provided with a nitrogen outlet pipe, the mixed gas pressure stabilizing tank being provided with a mixed gas inlet pipe, the hydrogen outlet pipe and the nitrogen outlet pipe being connected to the mixed gas inlet pipe, characterized in that: The hydrogen outlet pipe is equipped with a gas mass flow control valve, and the nitrogen outlet pipe is equipped with a gas flow meter. It also includes a PLC controller, and the gas flow meter and the gas mass flow control valve are all electrically connected to the PLC controller. ​ 2. The automatic proportioning hydrogen-nitrogen gas mixing system according to claim 1, characterized in that: The hydrogen pressure stabilizing tank is also equipped with a hydrogen pressure gauge and a hydrogen pressure relief valve.

3. The automatic proportioning hydrogen-nitrogen gas mixing system according to claim 1 or 2, characterized in that: The hydrogen pressure stabilizing tank is also equipped with a hydrogen inlet pipe for connecting to a hydrogen source, and a manual hydrogen shut-off valve is also provided on the hydrogen outlet pipe.

4. The automatic proportioning hydrogen-nitrogen gas mixing system according to claim 1, characterized in that: The nitrogen pressure stabilizing tank is also equipped with a nitrogen pressure gauge and a nitrogen pressure relief valve.

5. An automatic hydrogen-nitrogen mixing system according to claim 1 or 4, characterized in that: The nitrogen pressure stabilizing tank is also equipped with a nitrogen inlet pipe for connecting to a nitrogen source, and a nitrogen outlet pipe is also equipped with a manual nitrogen shut-off valve.

6. The automatic proportioning hydrogen-nitrogen gas mixing system according to claim 1, characterized in that: The gas mixture pressure stabilizing tank is also equipped with a gas mixture pressure gauge and a gas mixture pressure relief valve.

7. The automatic proportioning hydrogen-nitrogen gas mixing system according to claim 1 or 6, characterized in that: The gas mixture pressure stabilizing tank is also equipped with a gas mixture outlet pipe for connecting to the gas consumption end, and the gas mixture outlet pipe is equipped with a manual gas mixture outlet valve.

8. The automatic hydrogen-nitrogen gas mixing system according to claim 7, wherein: A gas stirrer is connected in series on the gas mixture inlet pipe.

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