Monitoring system of LPG (Liquefied Petroleum Gas) storage tank

Abstract

The monitoring system comprises a controller, the input end of the controller is connected with an operation panel and an acquisition module used for acquiring state information of the LPG storage tank, and the output end of the controller is connected with a controller used for controlling starting or stopping of an electromagnetic valve, a hydrocarbon pump, a compressor and a fire fighting unit; the controller is connected with an upper computer used for displaying state information. According to the LPG storage tank monitoring system, the acquisition module transmits acquired information to the controller, the controller processes data and sends state information to the upper computer, a user can monitor the real-time state of the LPG storage tank through the upper computer, faults can be found in the first time, corresponding measures can be taken, and safety is improved; besides, the output end of the controller is connected with a controller used for controlling starting or stopping of the electromagnetic valve, the hydrocarbon pump, the compressor and the fire-fighting unit, when a fault is found, if the user does not conduct operation at the first time, the controller stops the electromagnetic valve, the hydrocarbon pump and the compressor and starts the fire-fighting unit, and safety is further improved.

Description

Technical Field

[0001] The invention relates to a control system, in particular to a monitoring system for an LPG spherical tank. Background Art

[0002] Liquefied petroleum gas (LPG), as an important energy source, is stored in a tank container in liquid form under a specific pressure. Nowadays, the application scenarios of LPG are becoming more and more extensive, making the management and safety monitoring of LPG tanks more and more critical.

[0003] In the prior art, when the system needs to be disconnected or the staff wants to know the operating status of the equipment, they need to go to the site to check the relevant situation. It is impossible to obtain the liquid level, pressure, flammable gas leakage and other parameters in the LPG tank in the first time. In addition, if the corresponding measures cannot be taken in time when the fault occurs, it may cause great damage to people and equipment. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a monitoring system for an LPG storage tank.

[0005] The technical solution adopted by the present invention to solve its technical problem is: A monitoring system for an LPG storage tank comprises a controller, wherein an input end of the controller is connected to an operation panel and a collection module for obtaining status information of the LPG storage tank, and an output end is connected to a control module for starting or stopping a solenoid valve, a hydrocarbon pump, a compressor and a fire fighting unit; and the controller is connected to a host computer for displaying status information.

[0006] The controller adopts Siemens S7-200SMART series programmable logic control PLC.

[0007] The acquisition module includes a liquid level detector, a temperature detector, a pressure detector, a flow meter, a fire detector and a gas leakage detector. The liquid level detector is used to obtain the liquid level height of the LPG storage tank and output the liquid level information. The temperature detector is used to obtain the temperature of the LPG storage tank and output the temperature information. The pressure detector is used to obtain the pressure of the LPG storage tank and output the pressure information. The flow meter is used to obtain the amount of flowing out of the LPG storage tank or flowing into the LPG storage tank and output the flow information. The fire detector is used to detect the concentration of combustible gas in the LPG storage tank and output an alarm signal. The gas leakage detector is used to detect the concentration of leaked gas and output a leakage signal. The controller receives the liquid level information, temperature information, pressure information, flow information, alarm signal and leakage signal and then outputs a control signal.

[0008] The solenoid valve, hydrocarbon pump, compressor and fire fighting unit are used to receive the control signal to start or stop themselves.

[0009] The fire fighting unit comprises an audible and visual alarm, a fire fighting water pump and a fire fighting solenoid valve. The audible and visual alarm is arranged on the outside of the LPG storage tank. The water pipe of the fire fighting water pump extends into the LPG storage tank. The fire fighting solenoid valve is installed in the water pipe.

[0010] The operation panel is provided with two control buttons, manual control and automatic control. Click the start interface of the operation panel, and a selection box for automatic or not pops up. If you select no, you will enter the manual control mode. If you select yes, you will enter the automatic control mode.

[0011] As a further improvement of the present invention, in the manual control mode, the operator can independently control the start or stop of the solenoid valve, the hydrocarbon pump and the compressor.

[0012] As a further improvement of the present invention, in the automatic control mode, the acquisition module outputs liquid level information, temperature information, pressure information, flow information, alarm signal and leakage signal to the controller, and the controller determines whether the liquid level information, temperature information, pressure information and leakage signal exceed the safety range. If they exceed the safety range, the solenoid valve, hydrocarbon pump and compressor are closed, and the sound and light alarm is started. If they do not exceed the safety range, no operation is performed; the controller determines whether the alarm signal detects a fire. If the detection result is yes, the solenoid valve, hydrocarbon pump and compressor are closed, and the sound and light alarm, fire water pump and fire solenoid valve are started. If the detection result is no, no operation is performed.

[0013] The safety range of the liquid level information is between 10% and 90% of the tank volume; the safety range of the temperature information is between -10°C and 40°C; the safety range of the pressure information is between 0.3MPa and 1.2MPa; the safety range of the leakage signal is when the leakage gas concentration is lower than 60% of the measuring range.

[0014] The controller uploads the judgment results, detection results and operation instructions to the host computer for data backup.

[0015] The beneficial effects of the present invention are as follows: an acquisition module for acquiring status information of the LPG storage tank is arranged in the LPG storage tank of the present invention, the acquisition module transmits the acquired information to the controller, the controller processes the data and sends the status information to the host computer, the user can monitor the real-time status of the LPG storage tank through the host computer, can find faults in the first time and take corresponding measures, thereby improving safety; in addition, the output end of the controller is connected with a control for controlling the start or stop of the solenoid valve, hydrocarbon pump, compressor and fire fighting unit. When a fault is found, if the user does not operate in the first time, the controller stops the solenoid valve, hydrocarbon pump and compressor, and starts the fire fighting unit, thereby further improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 It is the electrical connection principle diagram of the present invention.

[0018] Figure 2 It is the electrical connection schematic diagram of the fire protection unit.

[0019] Figure 3 It is a structural schematic diagram of the present invention.

[0020] Figure 4 It is the operation logic diagram of the monitoring system of the present invention. DETAILED DESCRIPTION

[0021] To make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in combination with specific implementations and with reference to the accompanying drawings. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0022] It is to be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention.

[0023] Some embodiments of the present invention are described below in conjunction with the accompanying drawings.

[0024] Reference Figures 1 to 3 , a monitoring system for an LPG storage tank, comprising a controller 1, the input end of the controller 1 is connected to an operation panel 2 and a collection module 3 for obtaining LPG storage tank status information, and the output end is connected to a control panel 4, a hydrocarbon pump 5, a compressor 6 and a fire unit 7 for starting or stopping; the controller 1 is connected to a host computer 8 for displaying status information. The present invention is provided with a collection module 3 for obtaining LPG storage tank status information in the LPG storage tank, the collection module 3 transmits the obtained information to the controller 1, the controller 1 processes the data and sends the status information to the host computer 8, the user can monitor the real-time status of the LPG storage tank through the host computer 8, can find faults in the first time and take corresponding measures, and improve safety; in addition, the output end of the controller 1 is connected to a control panel 4, a hydrocarbon pump 5, a compressor 6 and a fire unit 7 for starting or stopping. When a fault is found, if the user does not operate in the first time, the controller stops the solenoid valve, hydrocarbon pump and compressor, and starts the fire unit, further improving safety.

[0025] In this embodiment, the controller 1 adopts a Siemens S7-200SMART series programmable logic control PLC. The controller 1 has functions such as data acquisition and conversion, electric valve control and abnormal alarm. The controller 1 obtains the data of the acquisition module 3, converts the collected analog value, and feeds back the converted value and valve status data to the control system. The control system issues valve opening, closing, and opening adjustment instructions, and completes the start or stop of the solenoid valve 4, hydrocarbon pump 5, compressor 6 and fire unit 7 through the controller 1.

[0026] Specifically, the acquisition module 3 includes a liquid level detector 31, a temperature detector 32, a pressure detector 33, a flow meter 34, a fire detector 35 and a gas leakage detector 36. The liquid level detector 31 is used to obtain the liquid level height of the LPG storage tank and output the liquid level information. The temperature detector 32 is used to obtain the temperature of the LPG storage tank and output the temperature information. The pressure detector 33 is used to obtain the pressure of the LPG storage tank and output the pressure information. The flow meter 34 is used to obtain the amount of gas flowing out of the LPG storage tank or into the LPG storage tank and output the flow information. The fire detector 35 is used to detect the concentration of combustible gas in the LPG storage tank and output an alarm signal. The gas leakage detector 36 is used to detect the concentration of leaked gas and output a leakage signal. The controller 1 receives the liquid level information, temperature information, pressure information, flow information, alarm signal and leakage signal and then outputs a control signal. The solenoid valve 4, hydrocarbon pump 5, compressor 6 and fire unit 7 are used to receive the control signal to start or stop themselves. In this embodiment, refer to Figure 3 The line segment with an arrow is the flow pipeline of LPG, and the line segment with only a line segment is an electrical connection line; the liquid level detector 31, the temperature detector 32, the pressure detector 33, the fire detector 35 and the gas leakage detector 36 are arranged in the LPG storage tank, and the compressor, the solenoid valve 4, the hydrocarbon pump 5 and the flow meter 34 are arranged on the flow pipeline to improve the accuracy of the data and reduce errors.

[0027] In this embodiment, the fire fighting unit 7 includes an audible and visual alarm 71, a fire fighting water pump 72 and a fire fighting solenoid valve 73. The audible and visual alarm 71 is arranged on the outside of the LPG tank. The water pipe of the fire fighting water pump 72 extends into the LPG tank. The fire fighting solenoid valve 73 is installed in the water pipe. The audible and visual alarm 71 includes a buzzer and an LED light. When the audible and visual alarm 71 is started, the buzzer sounds and the LED light lights up, which serves as a warning. The fire fighting water pump 72 includes foam liquid and fire fighting water. When the fire fighting detector 35 detects a fire and sends an alarm signal, the controller 1 sends a control signal after receiving the alarm signal. The fire fighting water pump 72 sprays the foam liquid and fire fighting water to the accident tank at the fastest speed to reduce the damage to people and equipment.

[0028] Reference Figure 4, Figure 4 This is a monitoring system operation logic diagram given by the present invention. In the present invention, the operation panel 2 is provided with two control modes: manual control and automatic control. Specifically, by clicking the start interface of the operation panel 2, a selection box for whether to automatically control is popped up. If no is selected, the manual control mode is entered. If yes is selected, the automatic control mode is entered. The operator can freely select the control mode, which is convenient for use.

[0029] In this embodiment, in the manual control mode, the operator can control the solenoid valve 4, hydrocarbon pump 5 and compressor 6 individually. For example, if the solenoid valve 4, hydrocarbon pump 5 and compressor 6 are to be inspected or repaired individually, the power supply or operation of the solenoid valve 4, hydrocarbon pump 5 and compressor 6 can be directly stopped, thereby making maintenance more convenient.

[0030] In this embodiment, in the automatic control mode, the controller 1 automatically obtains the detection values ​​of the liquid level detector 31, the temperature detector 32, the pressure detector 33, the flow meter 34, the fire detector 35 and the gas leakage detector 36. When any of the values ​​exceeds the set range, an alarm signal will be issued and the corresponding valve equipment will be automatically started / stopped.

[0031] Specifically, the liquid level detector 31 detects the liquid level value of the LPG storage tank. The liquid level detector 31 can be an optical fiber sensor. The working principle of the optical fiber sensor is that the light source emits light and is sent to the modulator through the optical fiber. After the measured parameter interacts with the light entering the modulation area, the optical properties of the light change, including changes in the intensity, wavelength, frequency, phase, and normal state of the light. Then, the light is sent to the optical detector through the optical fiber, and the measured parameter is obtained after demodulation. The measured parameter is transmitted back to the controller 1, and the controller 1 compares whether it exceeds the preset value range. If it exceeds the range, the solenoid valve, hydrocarbon pump and compressor are closed, and the sound and light alarm is started. If it does not exceed the preset range, no action is performed. Among them, the preset value range of the liquid level in the LPG storage tank is 10%-90% of the tank volume. If the liquid level is too low, it may cause the pressure in the tank to be unstable; if the liquid level is too high, the liquid expansion when the temperature rises may cause the pressure to rise sharply and exceed the safety limit. The controller 1 monitors the liquid level of the LPG storage tank in real time. If the liquid level is too low, the staff can be reminded to replenish the liquid in time to improve the safety of the LPG storage tank.

[0032] The temperature detector 32 may be a temperature sensor, which is used to detect the temperature value in the LPG storage tank. The temperature value is transmitted back to the controller 1, and the controller 1 compares whether it exceeds the preset value range. If it exceeds the range, the solenoid valve, hydrocarbon pump and compressor are closed, and the sound and light alarm is activated. If the detected value does not exceed the preset range, no action is performed. Among them, the preset value range of the temperature in the LPG storage tank is between -10℃ and 40℃. This low-temperature storage method can reduce the vapor pressure of LPG, and a large amount of LPG can be stored at a lower pressure. The controller 1 monitors the temperature of the LPG storage tank in real time to prevent the temperature in the LPG storage tank from being too high or too low, thereby improving the safety of the LPG storage tank.

[0033] The pressure detector 33 is used to detect the pressure value in the LPG storage tank. The pressure value is transmitted back to the controller 1, and the controller 1 compares whether it exceeds the preset value range. If it exceeds the range, the solenoid valve, hydrocarbon pump and compressor are closed, and the sound and light alarm is activated. If the detected value does not exceed the preset range, no action is performed. Among them, the preset value range of the pressure in the LPG storage tank is between 0.3MPa-1.2MPa, which can monitor the pressure in the LPG storage tank in real time and improve the safety of the LPG storage tank.

[0034] The gas leakage detector 36 is used to detect whether there is a leak in the LPG tank. It is installed outside the LPG tank. The gas leakage detector 36 can be a gas sensor. The working principle of the gas sensor is that when the gas contacts the surface of the gas sensor, it will be adsorbed on the material of the gas sensor; the adsorption of the gas will cause the conductivity of the gas sensor material to change. The gas sensor converts the detected conductivity change into a corresponding electrical signal. After amplification, filtering and other processing, the electrical signal is transmitted to the controller 1. The controller 1 compares whether it exceeds the preset value range. If it exceeds the range, the solenoid valve, hydrocarbon pump and compressor are closed, and the sound and light alarm is started. If the detected value does not exceed the preset range, no action is performed. Among them, the preset value range of the concentration of gas leaking from the LPG tank is lower than 60% of the range, which can monitor whether the LPG tank is leaking in real time and improve the safety of the LPG tank.

[0035] The fire detector 35 is a combustible gas detector. When a fire occurs, the sound and light alarm 71 is used to promptly remind the staff and respond in time. The controller 1 simultaneously closes the solenoid valve 4, the hydrocarbon pump 5 and the compressor 6, and starts the sound and light alarm 71, the fire solenoid valve 73 and the fire pump 72. The fire solenoid valve 73 is used to open the fire water pipe to facilitate the outflow of the fire liquid. The fire pump 72 is used to provide fire liquid, which can deal with the fire in time and improve the efficiency of fire extinguishing. In this embodiment, after the fire solenoid valve 73 and the fire pump 72 are in operation for 5 minutes, the controller 1 issues a stop command, and the fire solenoid valve 73 and the fire pump 72 are closed. Then the fire detector 35 is used to detect whether it is still in a fire state. If it is detected that it is still in a fire state, the controller 1 continues to start the fire sprinkler operation. If it is detected that there is no fire state, no operation is performed, but the detection result will be uploaded to the host computer 8.

[0036] The controller 1 uploads the judgment result, the detection result and the operation instruction to the host computer 8 for data backup.

[0037] Working principle: The acquisition module 3 obtains the status information such as the liquid level information, temperature information, pressure information and flow information in the LPG storage tank. After receiving the status information, the controller 1 sends it to the host computer 8 and displays the status information on the host computer 8, so that the user can monitor the LPG storage tank in real time. In addition, the output end of the controller 1 is connected to the start or stop of the solenoid valve, hydrocarbon pump, compressor and fire fighting unit. When a fault is found, if the user does not operate it in the first time, the controller stops the solenoid valve, hydrocarbon pump and compressor, and starts the fire fighting unit, further improving safety.

[0038] The above implementation modes cannot limit the protection scope of the present invention. The equivalent modifications and changes made by those skilled in the art without departing from the overall concept of the present invention are still within the scope of the present invention.

Claims

1. A monitoring system for an LPG storage tank, comprising a controller (1), characterized in that The input end of the controller (1) is connected to an operation panel (2) and a collection module (3) for acquiring LPG storage tank status information, and the output end is connected to a control module for controlling the start or stop of a solenoid valve (4), a hydrocarbon pump (5), a compressor (6) and a fire fighting unit (7); the controller (1) is connected to a host computer (8) for displaying status information.

2. The monitoring system for LPG storage tank according to claim 1 is characterized in that The controller (1) adopts a Siemens S7-200SMART series programmable logic control PLC.

3. The monitoring system for LPG storage tank according to claim 2 is characterized in that The acquisition module (3) comprises a liquid level detector (31), a temperature detector (32), a pressure detector (33), a flow meter (34), a fire detector (35) and a gas leakage detector (36); the liquid level detector (31) is used to obtain the liquid level height of the LPG storage tank and output liquid level information; the temperature detector (32) is used to obtain the temperature of the LPG storage tank and output temperature information; the pressure detector (33) is used to obtain the pressure of the LPG storage tank and output pressure information; the flow meter (34) is used to obtain the amount of gas flowing out of or into the LPG storage tank and output flow information; the fire detector (35) is used to detect the concentration of combustible gas in the LPG storage tank and output an alarm signal; the gas leakage detector (36) is used to detect the concentration of leaked gas and output a leakage signal; and the controller (1) outputs a control signal after receiving the liquid level information, temperature information, pressure information, flow information, alarm signal and leakage signal.

4. The monitoring system for LPG storage tank according to claim 3 is characterized in that The solenoid valve (4), hydrocarbon pump (5), compressor (6) and fire fighting unit (7) are used to receive the control signal to start or stop themselves.

5. The monitoring system for LPG storage tank according to claim 4, characterized in that The fire fighting unit (7) comprises an audible and visual alarm (71), a fire fighting water pump (72) and a fire fighting solenoid valve (73); the audible and visual alarm (71) is arranged outside the LPG storage tank; a water pipe of the fire fighting water pump (72) extends into the LPG storage tank; and the fire fighting solenoid valve (73) is installed in the water pipe.

6. The monitoring system for LPG storage tank according to claim 5, characterized in that The operation panel (2) is provided with two control buttons, manual control and automatic control. When the start interface of the operation panel (2) is clicked, a selection box for whether to automatically start or not pops up. If "no" is selected, the manual control mode is entered. If "yes" is selected, the automatic control mode is entered.

7. The monitoring system for LPG storage tank according to claim 6, characterized in that: In the manual control mode, the operator can individually control the start or stop of the solenoid valve (4), the hydrocarbon pump (5) and the compressor (6).

8. The monitoring system for LPG storage tank according to claim 6, characterized in that: In the automatic control mode, the acquisition module (3) outputs liquid level information, temperature information, pressure information, flow rate information, alarm signal and leakage signal to the controller (1); the controller (1) determines whether the liquid level information, temperature information, pressure information and leakage signal exceed a safety range; if they exceed the safety range, the solenoid valve (4), hydrocarbon pump (5) and compressor (6) are closed, and the sound and light alarm (71) is started; if they do not exceed the safety range, no operation is performed; the controller (1) determines whether the alarm signal detects a fire; if the detection result is yes, the solenoid valve (4), hydrocarbon pump (5) and compressor (6) are closed, and the sound and light alarm (71), fire water pump (72) and fire solenoid valve (73) are started; if the detection result is no, no operation is performed.

9. The monitoring system for LPG storage tank according to claim 8, characterized in that The safety range of the liquid level information is between 10% and 90% of the tank volume; the safety range of the temperature information is between -10°C and 40°C; the safety range of the pressure information is between 0.3MPa and 1.2MPa; the safety range of the leakage signal is when the leakage gas concentration is lower than 60% of the measuring range.

10. The monitoring system for LPG storage tank according to claim 8, characterized in that The controller (1) uploads the judgment result, the detection result and the operation instruction to the host computer (8) for data backup.

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