Liquid level measurement and alarm system for seawater desalination chemical cleaning tank

Abstract

The utility model discloses a liquid level measurement and alarm system for a seawater desalination chemical cleaning tank, the chemical cleaning tank is provided with a chemical cleaning pump, a heater in the tank and a heater field control box, and the system comprises a magnetic turning plate liquid level meter, a reed switch device, a loop digital display meter, a PLC (Programmable Logic Controller) and an industrial personal computer, the magnetic turning plate liquid level meter is communicated with the chemical cleaning tank, the reed pipe device is installed on the outer side of the magnetic turning plate liquid level meter, the reed pipe device is connected with the loop digital display meter, a reed pipe magnetic control switch is arranged on the reed pipe device, and the reed pipe magnetic control switch is connected with the chemical cleaning pump and the heater field control box. The heater field control box is connected with the PLC, the loop digital display meter, the PLC and the industrial personal computer are connected in sequence, dual-redundancy display is achieved on site, and a high and low liquid level alarm function is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of cleaning tank liquid level detection, and in particular relates to a seawater desalination chemical cleaning tank liquid level measurement and alarm system. Background Art

[0002] Magnetic flap level gauges can be used for medium level detection in various towers, tanks, spherical containers, boilers and other equipment. This series of level gauges can be sealed and are suitable for high temperature, high pressure, corrosion-resistant occasions, and have a large measurement range. The magnetic flap level gauge is developed based on the buoyancy principle and magnetic coupling. Its working principle is: when the liquid level in the measured container rises and falls, the float in the main pipe of the level gauge also rises and falls accordingly. The permanent magnet in the float is transmitted to the field indicator through magnetic coupling to drive the red and white flip column on the flip plate to flip 180°. When the liquid level rises, the flip column turns from white to red, and when the liquid level drops, the flip column turns from red to white. The red and white boundary position of the indicator is the actual height of the liquid level, thereby realizing the indication of the liquid level. At present, the remote transmission signal of the magnetic flap level gauge on the market is mainly realized by adding a remote transmission instrument with a reed switch. This method has the following shortcomings: 1. The intuitiveness of the field instrument does not have a dual redundancy function and cannot guarantee the accuracy of the single display of the field instrument; 2. The intuitive local signal is often used as the basis for important operations of the operator, and the 4-20mA analog signal alone in the control room is not enough to determine the accuracy of the signal. Utility Model Content

[0003] In order to overcome the above technical problems existing in the prior art, the purpose of the utility model is to provide a seawater desalination chemical cleaning tank level measurement and alarm system, which realizes dual redundant display on site and has an alarm function.

[0004] The utility model provides a liquid level measurement and alarm system for a seawater desalination chemical cleaning tank. The chemical cleaning tank is provided with a chemical cleaning pump, a tank heater and a heater field control box. The system comprises a magnetic flap liquid level gauge, a reed switch device, a loop digital display, a PLC controller and an industrial computer. The magnetic flap liquid level gauge is connected to the chemical cleaning tank. The reed switch device is installed on the outside of the magnetic flap liquid level gauge. The reed switch device is connected to the loop digital display. A reed switch magnetically controlled switch is provided on the reed switch device. The reed switch magnetically controlled switch is connected to the chemical cleaning pump and the heater field control box. The heater field control box is connected to the PLC controller. The loop digital display, the PLC controller and the industrial computer are connected in sequence.

[0005] The main body tube of the magnetic flap level gauge is provided with a magnetic float and a magnetic flip column indicator. The magnetic float transmits signals to the magnetic flip column indicator through magnetic coupling. The magnetic flip column indicator is provided with red and white flip columns.

[0006] The reed switch magnetic control switch includes a high liquid level protection magnetic control switch and a low liquid level protection magnetic control switch.

[0007] A drain valve is provided at the bottom of the main body pipe of the magnetic flap liquid level gauge.

[0008] The upper and lower ends of the magnetic flap level gauge are respectively connected to the upper and lower parts of the chemical cleaning tank.

[0009] The utility model provides a seawater desalination chemical cleaning tank liquid level measurement and alarm system, which has the beneficial effect of real-time display of on-site liquid level conditions, dual redundant display through a magnetic flap liquid level gauge and a loop digital display, and the signal is transmitted to an industrial computer for remote display through a PLC controller. During system operation, the chemical cleaning pump and the tank heater are protected from high and low liquid levels according to the actual liquid level conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the utility model;

[0011] Figure 2 It is a schematic diagram of the internal structure of an embodiment of the utility model.

[0012] Note in the figure:

[0013] 1. Chemical cleaning tank; 2. Magnetic flap level gauge; 3. Reed switch device; 4. High liquid level protection magnetic switch; 5. Low liquid level protection magnetic switch; 6. Loop digital display; 7. PLC controller; 8. Industrial computer; 9. Tank heater; 10. Heater on-site control box; 11. Magnetic float; 12. Magnetic flap indicator; 13. Drain valve. DETAILED DESCRIPTION

[0014] With reference to the accompanying drawings and in combination with an embodiment, a seawater desalination chemical cleaning tank level measurement and alarm system provided by the utility model is described in detail below.

[0015] Example

[0016] Reference Figure 1-Figure 2In this embodiment, a seawater desalination chemical cleaning tank level measurement and alarm system is provided. The chemical cleaning tank 1 is provided with a chemical cleaning pump, a tank heater 9 and a heater field control box 10. The system includes a magnetic flap level gauge 2, a reed switch device 3, a loop digital display 6, a PLC controller 7 and an industrial computer 8. The magnetic flap level gauge 2 is connected to the chemical cleaning tank 1. The reed switch device 3 is installed on the outside of the magnetic flap level gauge 2. The reed switch device 3 is connected to the loop digital display 6. A reed switch magnetic switch is provided on the reed switch device 3. The reed switch magnetic switch is connected to the chemical cleaning pump and the heater field control box 10. The heater field control box 10 is connected to the PLC controller 7. The loop digital display 6, the PLC controller 7 and the industrial computer 8 are connected in sequence.

[0017] The main body tube of the magnetic flap level gauge 2 is provided with a magnetic float 11 and a magnetic column indicator 12. The magnetic float 11 transmits signals to the magnetic column indicator 12 through magnetic coupling. The magnetic column indicator 12 is provided with red and white columns.

[0018] The reed switch magnetic control switch comprises a high liquid level protection magnetic control switch 4 and a low liquid level protection magnetic control switch 5 .

[0019] A drain valve 13 is provided at the bottom of the main body tube of the magnetic flap level gauge 2.

[0020] The upper and lower ends of the magnetic flap level gauge are respectively connected to the upper and lower parts of the chemical cleaning tank.

[0021] The magnetic flap level gauge is a connected measuring device. When the liquid level in the tank changes, the magnetic float in the body tube of the level gauge also rises and falls. The permanent magnet in the magnetic float is transmitted to the magnetic flip column indicator through magnetic coupling, driving the red and white flip columns to flip 180°. When the liquid level rises, the red and white flip columns change from white to red, and when the liquid level drops, the red and white flip columns change from red to white. The red and white junction of the magnetic flip column indicator is the actual height of the liquid level inside the chemical cleaning tank, thereby achieving a clear indication of the liquid level. The measurement of the reed switch device is non-contact. Through the magnetic float in the magnetic flap level gauge, the reed switch elements in the conduit are activated in sequence through magnetic coupling, and the resistance signal changes are obtained. The output is a 4-20mA current signal that changes with the liquid level change. The current signal is transmitted to the on-site loop digital display, and the loop digital display displays the real-time liquid level on-site for on-site personnel to view. At the same time, a 4-20mA current signal is output to the PLC controller. The industrial computer receives and displays the real-time liquid level and records the liquid level data curve. When the on-site liquid level reaches the high and low liquid level alarm values, the reed switch magnetic control switch outputs an alarm signal, which is connected to the on-site control box of the chemical cleaning pump and heater, thus forming a complete and reliable seawater desalination chemical cleaning tank liquid level automatic measurement and alarm system.

[0022] During the chemical cleaning process, according to the process requirements, the agent in the tank needs to be heated to a certain temperature, and the heater in the tank needs to be completely immersed below the liquid surface when working. Once it is out of the liquid surface and "dry burning" occurs, the heater is easily damaged. Therefore, this system is equipped with a low liquid level protection magnetic control switch to protect the heater.

[0023] During the chemical cleaning process, the circulating water in the tank flows very fast and the chemicals are prone to foaming. To prevent the liquid level from being too high and causing the chemicals to leak out, this system is equipped with a high liquid level protection magnetic control switch to avoid wasting chemicals.

[0024] This system has basically achieved automation and unattended operation. On-site personnel only need to play an auxiliary role on site, which greatly reduces the workload of operators and also reduces equipment damage, reagent waste and environmental pollution.

Claims

1. A level measurement and alarm system for a seawater desalination chemical cleaning tank, wherein the chemical cleaning tank is provided with a chemical cleaning pump, a tank heater and a heater field control box, and wherein: It includes a magnetic flap level gauge, a reed switch device, a loop digital display, a PLC controller and an industrial computer. The magnetic flap level gauge is connected to the chemical cleaning tank. The reed switch device is installed on the outside of the magnetic flap level gauge. The reed switch device is connected to the loop digital display. The reed switch device is provided with a reed switch magnetic switch. The reed switch magnetic switch is connected to the chemical cleaning pump and the heater field control box. The heater field control box is connected to the PLC controller. The loop digital display, PLC controller and industrial computer are connected in sequence.

2. A seawater desalination chemical cleaning tank liquid level measurement and alarm system according to claim 1, characterized in that: The main body tube of the magnetic flap level gauge is provided with a magnetic float and a magnetic flip column indicator. The magnetic float transmits signals to the magnetic flip column indicator through magnetic coupling. The magnetic flip column indicator is provided with red and white flip columns.

3. A seawater desalination chemical cleaning tank liquid level measurement and alarm system according to claim 1, characterized in that: The reed switch magnetic control switch includes a high liquid level protection magnetic control switch and a low liquid level protection magnetic control switch.

4. A seawater desalination chemical cleaning tank liquid level measurement and alarm system according to claim 1, characterized in that: A drain valve is provided at the bottom of the main body pipe of the magnetic flap liquid level gauge.

5. A seawater desalination chemical cleaning tank liquid level measurement and alarm system according to claim 1, characterized in that: The upper and lower ends of the magnetic flap level gauge are respectively connected to the upper and lower parts of the chemical cleaning tank.

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