An automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer

Abstract

This utility model belongs to the field of automatic measurement technology, specifically relating to an automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer. It includes a sampling tube, one end of which extends into a nitrate phosphate neutralization tank, and the other end of which is located outside the tank and connected to an analytical flow cell. A sampling container is connected to the upper part of the analytical flow cell via a pipeline. The upper part of the sampling container is connected to the inlet of a vacuum pump via a pipeline equipped with a suction solenoid valve. A pH probe is installed on the analytical flow cell to detect the pH value of the mother liquor flowing through it. The pH probe, suction solenoid valve, and vacuum pump are all electrically connected to a PLC controller. This utility model uses the cooperation of the vacuum pump and sampling tube to extract the mother liquor for pH measurement. During extraction, the mother liquor is in a sealed environment, preventing leakage. Simultaneously, the sampling container and integrated temperature transmitter effectively prevent the mother liquor from entering the vacuum pump.

Description

Technical Field

[0001] This utility model belongs to the field of automatic measurement technology, specifically relating to an automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer. Background Technology

[0002] In the production of nitrophosphate fertilizer, the pH value of the viscous mother liquor is a crucial process parameter, directly affecting the product quality and production efficiency. During the neutralization process of the nitrophosphate mother liquor, as the pH value increases, free calcium ions are converted into a solid state through a reaction. If the pH value is too high, phosphate degradation may occur, reducing the P2O5 content in the finished product and rendering it substandard.

[0003] For many years, the pH value of the viscous mother liquor in nitrate phosphate fertilizer production plants has faced the technical challenge of being difficult to measure accurately and automatically. Current pH measurement technology involves installing a sampling cylinder through an opening in the center of the neutralization tank, with sampling achieved through cylinder extension and retraction. However, over time, cylinder jamming and vibration caused by cylinder sealing ring failure can occur, leading to leakage of the mother liquor during sampling. This results in discontinuous pH measurements, and the leakage also causes waste and environmental pollution. Utility Model Content

[0004] This invention provides an automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer to address the above-mentioned problems.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer includes a sampling tube, one end of which extends into a nitrate phosphate neutralization tank, and the other end of which is located outside the nitrate phosphate neutralization tank and connected to an analytical flow cell. A sampling vessel is connected to the upper part of the analytical flow cell via a pipeline. The upper part of the sampling vessel is connected to the inlet of a vacuum pump via a pipeline equipped with a suction solenoid valve. A pH probe is installed on the analytical flow cell to detect the pH value of the mother liquor flowing through the analytical flow cell. The pH probe, suction solenoid valve, and vacuum pump are all electrically connected to a PLC controller.

[0007] Furthermore, an integrated temperature transmitter is installed in the lower middle part of the sampling vessel, and the integrated temperature transmitter is electrically connected to the PLC controller.

[0008] Furthermore, a backwashing pipeline is connected to the side of the analytical flow cell away from the sampling tube 1. A water pump and a backwashing solenoid valve are installed on the backwashing pipeline. The other end of the backwashing pipeline is connected to the demineralized water storage tank. Both the water pump and the backwashing solenoid valve are electrically connected to the PLC controller.

[0009] Furthermore, a backflush pipeline is connected to the sampling tank, and a backflush solenoid valve is installed on the backflush pipeline. The other end of the backflush solenoid valve is connected to the air outlet of the air compressor. Both the air compressor and the backflush solenoid valve are electrically connected to the PLC controller.

[0010] Furthermore, the suction solenoid valve, backwash solenoid valve, and backflush solenoid valve are all two-position three-way solenoid valves with manual operation function.

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] This invention uses a vacuum pump and sampling tube to extract mother liquor for pH measurement. During the extraction process, the mother liquor is in a sealed environment, preventing leakage. Simultaneously, the sampling tank and integrated temperature transmitter effectively prevent the mother liquor from entering the vacuum pump. The sampling tank design provides a buffer for the extraction of mother liquor, preventing it from directly entering the vacuum pump. The integrated temperature transmitter detects the temperature; when the mother liquor level in the sampling tank reaches the integrated temperature transmitter, the temperature signal detected by the transmitter rises instantaneously. Upon receiving the signal, the PLC controller can promptly shut down the vacuum pump and the suction solenoid valve, thus preventing the mother liquor from entering the vacuum pump.

[0013] This invention is equipped with a backwashing pipeline. After the pH measurement is completed, the mother liquor is backflowed into the phosphorus nitrate neutralization tank. Then, the analytical flow cell can be backwashed after the pH measurement is completed through the backwashing pipeline. At the same time, during the backwashing process, the demineralized water can also enter the sampling tank to clean the sampling tank. The cleaned demineralized water can be directly discharged into the phosphorus nitrate neutralization tank.

[0014] This invention features a backflush pipeline. After backwashing is completed, the backwash solenoid valve and suction solenoid valve are closed, the backflush solenoid valve is opened, and the air compressor is started to introduce backflush air into the sampling tank. This backflush air then backflushes the residual mother liquor and demineralized water in the sampling tank, analytical flow cell, and sampling tube into the nitrate phosphorus neutralization tank, ensuring the accuracy of the next pH measurement. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] In the diagram, 1 is the sampling tube, 2 is the phosphorus nitrate neutralization tank, 3 is the analytical flow cell, 4 is the sampling tank, 5 is the suction solenoid valve, 6 is the vacuum pump, 7 is the pH probe, 8 is the PLC controller, 9 is the integrated temperature transmitter, 10 is the backwash line, 11 is the water pump, 12 is the backwash solenoid valve, 13 is the demineralized water storage tank, 14 is the backflush line, 15 is the backflush solenoid valve, and 16 is the air compressor. Detailed Implementation

[0017] To further illustrate the technical solution of this utility model, the following embodiments will be used to further explain this utility model.

[0018] like Figure 1 As shown, an automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer includes a sampling tube 1, one end of which extends into a nitrate phosphate neutralization tank 2, and the other end of which is located outside the nitrate phosphate neutralization tank 2 and connected to an analytical flow cell 3. A sampling tank 4 is connected to the upper part of the analytical flow cell 3 via a pipeline. The upper part of the sampling tank 4 is connected to the inlet of a vacuum pump 6 via a pipeline equipped with a suction solenoid valve 5. A pH probe 7 is installed on the analytical flow cell 3 to detect the pH value of the mother liquor flowing through the analytical flow cell 3. An integrated temperature transmitter 9 is installed in the lower middle part of the sampling tank 4. A backwashing pipeline 10 is connected to the side away from the sampling tube 1. A water pump 11 and a backwashing solenoid valve 12 are installed on the backwashing pipeline 10. The other end of the backwashing pipeline 10 is connected to the demineralized water storage tank 13. A backflush pipeline 14 is connected to the sampling tank 4. A backflush solenoid valve 15 is installed on the backflush pipeline 14. The other end of the backflush solenoid valve 15 is connected to the air outlet of the air compressor 16. The pH probe 7, integrated temperature transmitter 9, water pump 11, backwashing solenoid valve 12, air compressor 16, backflush solenoid valve 15, suction solenoid valve 5, and vacuum pump 6 are all electrically connected to the PLC controller 8.

[0019] The suction solenoid valve 5, backwash solenoid valve 12, and backflush solenoid valve 15 are all two-position three-way solenoid valves with manual operation function.

[0020] Working principle: When pH measurement is required, the PLC controller 8 closes the backwash solenoid valve 12 and the backflush solenoid valve 15, opens the suction solenoid valve 5, and then starts the vacuum pump 6 to suction the mother liquor. After the integrated temperature transmitter 9 detects a high temperature signal, it feeds the high temperature signal back to the PLC controller 8. At this time, the liquid level of the mother liquor has reached the height of the integrated temperature transmitter 9, so the PLC controller 8 controls the vacuum pump 6 to stop working and closes the suction solenoid valve 5. At the same time, the pH probe 7 measures the pH of the mother liquor in the analysis flow cell 3. The measured value is fed back to the PLC controller. Then, the PLC controller controls the backwash solenoid valve 12 to open and starts the water pump 11 to backwash the analysis flow cell 3 and the sampling tank 4. When the backwash time reaches the set value, the backwashing stops. The PLC controller 8 controls the water pump 11 and the backwash solenoid valve 12 to close and controls the air compressor 16 and the backflush solenoid valve 15 to open and perform backflush. When the backflush time reaches the set value, the backflush stops and the PLC controller 8 controls the air compressor 16 and the backflush solenoid valve 15 to close, thus completing one pH measurement.

[0021] The foregoing has shown and described the main features and advantages of this utility model. It will be apparent to those skilled in the art that this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model.

[0022] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An automatic pH measuring device for viscous mother liquor of nitrate phosphate fertilizer, characterized in that: The system includes a sampling tube (1), one end of which extends into the phosphorus nitrate neutralization tank (2), and the other end of which is located outside the phosphorus nitrate neutralization tank (2) and connected to the analytical flow cell (3). A sampling tank (4) is connected to the upper part of the analytical flow cell (3) via a pipeline. The upper part of the sampling tank (4) is connected to the inlet of the vacuum pump (6) via a pipeline with a suction solenoid valve (5). A pH probe (7) is installed on the analytical flow cell (3) to detect the pH value of the mother liquor flowing through the analytical flow cell (3). The pH probe (7), suction solenoid valve (5) and vacuum pump (6) are all electrically connected to the PLC controller (8).

2. The device for automatic measurement of the viscosity of a nitrophosphate fertilizer mother liquor according to claim 1, characterized in that it comprises: An integrated temperature transmitter (9) is installed in the lower middle part of the sampling tank (4), and the integrated temperature transmitter (9) is electrically connected to the PLC controller (8).

3. The device according to claim 2, characterized in that it comprises a pH meter. A backwashing pipeline (10) is connected to the side of the analytical flow cell (3) away from the sampling tube (1). A water pump (11) and a backwashing solenoid valve (12) are installed on the backwashing pipeline (10). The other end of the backwashing pipeline (10) is connected to the demineralized water storage tank (13). The water pump (11) and the backwashing solenoid valve (12) are both electrically connected to the PLC controller (8).

4. The device according to claim 3, characterized in that: A backflush pipeline (14) is connected to the sampling tank (4), and a backflush solenoid valve (15) is provided on the backflush pipeline (14). The other end of the backflush solenoid valve (15) is connected to the air outlet of the air compressor (16). The air compressor (16) and the backflush solenoid valve (15) are both electrically connected to the PLC controller (8).

5. The device for automatic measurement of the viscosity of a nitrophosphate fertilizer mother liquor according to claim 4, characterized in that it comprises: The suction solenoid valve (5), backwash solenoid valve (12), and backflush solenoid valve (15) are all two-position three-way solenoid valves with manual operation function.

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