Centrifuge oxygen content monitoring system

Abstract

The utility model relates to the technical field of raw material medicine production, aims to solve the technical problem of safety risk caused by static electricity generated in the high-speed rotation process of a centrifugal machine, and discloses a centrifugal machine oxygen content monitoring system which comprises oxygen content monitoring equipment, the centrifugal machine, a reaction kettle, a mother liquid tank, a waste liquid tank and a liquid sealing tank. The centrifugal machine is connected with the reaction kettle through a material pipeline, the centrifugal machine is connected with the mother liquor tank through a pipeline, a nitrogen valve, an oxygen content probe and an oxygen monitoring circuit control circuit are arranged in the oxygen content monitoring equipment, the oxygen content monitoring equipment is connected with a PLC used for controlling the nitrogen valve, and the nitrogen pipeline is connected with the centrifugal machine through the nitrogen valve. And the mother liquor tank is connected with the oxygen content monitoring equipment through a gas sampling pipeline. An oxygen content monitoring system is optimized, the oxygen content is obtained in time through a gas sampling pipeline, original gas is driven by nitrogen, the nitrogen is controlled and adjusted, a power supply is cut off when the standard exceeds the standard, safety is ensured, risks are reduced, and accurate control over the oxygen content is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of raw drug production, in particular to a centrifuge oxygen content monitoring system. Background Art

[0002] In the production process of the reaction kettle for raw drugs, centrifuges are widely used. The centrifuge uses its high-speed rotating drum to separate the mixture into solids and liquids. However, in this process, the high-speed rotation of the centrifuge causes friction between the surface of its drum and the air and materials, thus easily accumulating static electricity. The accumulation of static electricity is a common phenomenon in industrial production, but in an environment full of organic solvents, the existence of static electricity brings serious safety hazards.

[0003] Inside the centrifuge, due to high-speed rotation, friction and collision will inevitably cause the generation of static electricity. If the accumulation of static charges cannot be released in a timely and effective manner, static sparks may be generated under certain conditions. And in the internal space of the centrifuge, it is often filled with flammable and explosive organic solvents such as ethanol and acetone. The vapors of these solvents form explosive gases when mixed with air within a certain concentration range. If static sparks are generated at this time, it may trigger an explosion, causing serious casualties and equipment damage.

[0004] In addition, during the operation of the centrifuge, in addition to the generation of static electricity, the internal friction of the equipment will also cause the temperature to rise, thus further increasing the risk of explosion. The drum and bearing parts of the centrifuge are high-risk areas for static electricity accumulation, especially in the case of high-speed operation and long-term operation, this risk will be more significant. Static electricity may not only cause sparks to trigger an explosion, but also interfere with the normal operation of electronic equipment and affect the stability of the production process.

[0005] In industrial practice, there have been many explosion accidents caused by static electricity. For example, in industries such as pharmaceuticals and chemicals, due to the lack of effective static electricity protection measures for production equipment, static sparks generated during operation ignited the solvent vapors, resulting in serious explosion accidents. These accidents not only brought huge economic losses, but also posed a major threat to the lives and safety of employees.

[0006] Therefore, in the process of raw drug production, especially when using a centrifuge for separation operations, the generation of static electricity and its potential explosion risk are important issues that cannot be ignored. The industrial community needs to attach great importance to this issue and take measures to control the oxygen content to ensure production safety. Content of the Utility Model

[0007] The purpose of the utility model is to provide a centrifuge oxygen content monitoring system to solve the technical problem of safety risks caused by static electricity generated during the high-speed rotation of the centrifuge.

[0008] To achieve the above object, the utility model provides a centrifuge oxygen content monitoring system, which includes an oxygen content monitoring device, a centrifuge, a reaction kettle, a mother liquor tank, a waste liquid tank and a liquid seal tank. The centrifuge is connected to the reaction kettle through a material pipeline, and the centrifuge is connected to the mother liquor tank through a pipeline. A nitrogen valve, an oxygen content probe and an oxygen monitoring circuit control circuit are arranged in the oxygen content monitoring device. The oxygen content monitoring device is connected with a PLC controller for controlling the nitrogen valve. The nitrogen pipeline is connected to the centrifuge through the nitrogen valve. The mother liquor tank is connected to the oxygen content monitoring device through a gas sampling pipeline.

[0009] The gas sampling pipeline is on the mother liquor tank to timely obtain the oxygen content in the centrifuge and avoid misjudgment. Nitrogen is introduced from the top of the centrifuge to drive the original gas to the mother liquor tank, reducing the oxygen content. The balance pipe prevents air from being sucked in due to negative pressure. The liquid seal tank prevents air from being sucked in due to negative pressure, forms a slightly positive pressure, and shows the gas flow. The oxygen content monitoring device monitors and alarms in real time, and the PLC controller adjusts the nitrogen valve to save nitrogen. The system monitors all the time, cuts off the power supply when the standard is exceeded to prevent flash explosion, ensures safety, reduces the explosion risk, and realizes precise control of the oxygen content.

[0010] Further, the mother liquor tank is connected to the waste liquid tank through a balance pipe, the waste liquid tank is connected to the liquid seal tank through a pipeline, and the liquid seal tank discharges the tail gas to a collection device.

[0011] Further, the oxygen monitoring circuit control circuit includes a constant potential circuit, a transimpedance amplifier circuit and an analog-to-digital conversion module. The constant potential circuit includes a first operational amplifier, a PMOS transistor and an electrochemical sensor for monitoring oxygen concentration. The inverting input terminal of the first operational amplifier is connected to the reference electrode of the electrochemical sensor through a resistor R6. A reference voltage is input to the positive input terminal of the first operational amplifier. The output terminal of the first operational amplifier is connected to the return electrode of the electrochemical sensor.

[0012] The working electrode of the electrochemical sensor is connected to the transimpedance amplifier circuit through a load resistor R8. The drain of the PMOS transistor is connected to the reference electrode of the electrochemical sensor. The source of the PMOS transistor is connected to the working electrode of the electrochemical sensor. The gate of the PMOS transistor is connected to the power supply VCC1.

[0013] By setting the PMOS transistor, when the circuit is powered on, the PMOS transistor is in an open state. When the circuit is powered off, the PMOS transistor conducts, so that the reference electrode and the working electrode are short-circuited together, and the electrochemical sensor is quickly short-circuited, avoiding the accumulation of a large amount of charge on the working electrode causing polarization phenomenon, and enabling a quick and stable start next time.

[0014] Further, the transimpedance amplifier circuit includes a second operational amplifier and a series voltage dividing circuit. The series voltage dividing circuit includes a resistor R11 and a resistor R12 connected in series. One end of the resistor R11 is connected to the power supply VCC1, one end of the resistor R12 is grounded, and the other ends of the resistor R11 and the resistor R12 are connected to form a voltage dividing node for providing a reference voltage. The voltage dividing node is connected to the non-inverting input terminal of the second operational amplifier through a current limiting resistor R13. The inverting input terminal of the second operational amplifier is connected to the working electrode of the electrochemical sensor through a load resistor R8. The output terminal of the second operational amplifier is connected to the analog-to-digital conversion module through a resistor R10.

[0015] The oxygen content monitoring system for a centrifuge provided by the present utility model has the following advantages:

[0016] The gas sampling pipeline is on the mother liquid tank to obtain the oxygen content of the centrifuge in a timely manner and avoid misjudgment. Nitrogen is introduced from the top of the centrifuge to drive the original gas to the mother liquid tank, reducing the oxygen content. The balance pipe prevents air from being sucked in due to negative pressure. The liquid seal tank prevents air from being sucked in due to negative pressure, forms a slightly positive pressure, and shows the gas flow. The oxygen content monitoring device monitors and alarms in real time, and the PLC controller adjusts the nitrogen valve to save nitrogen. The system monitors all the time, cuts off the power supply when the standard is exceeded to prevent flash explosion, ensures safety, reduces the explosion risk, and realizes precise control of the oxygen content. In addition, the polarization phenomenon caused by the accumulation of a large amount of charge on the working electrode is avoided through the oxygen monitoring circuit control circuit, enabling a quick and stable start next time. Description of the Drawings

[0017] Figure 1 is a schematic diagram of the oxygen content monitoring system for a centrifuge provided by the present utility model;

[0018] Figure 2 is a control diagram of the oxygen monitoring circuit provided by the present utility model.

[0019] In the figure: 11, reaction kettle; 12, PLC controller; 13, oxygen content monitoring device; 14, material pipeline; 15, gas pipeline; 16, centrifuge; 17, gas sampling pipeline; 18, mother liquid tank; 19, pneumatic pump; 20, waste liquid tank; 21, liquid seal tank; Q4, PMOS transistor; Q8, electrochemical sensor; U3, first operational amplifier; U4, analog-to-digital conversion module; U6, second operational amplifier. Detailed Embodiment

[0020] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0021] Refer to Figure 1, the utility model provides a centrifuge oxygen content monitoring system, which includes an oxygen content monitoring device 13, a centrifuge 16, a reaction kettle 11, a mother liquor tank 18, a pneumatic pump 19, a waste liquid tank 20 and a liquid seal tank 21. The centrifuge 16 is connected to the reaction kettle 11 through a material pipeline 14, and the centrifuge 16 is connected to the mother liquor tank 18 through a pipeline. The oxygen content monitoring device 13 is provided with a nitrogen valve, an oxygen content probe and an oxygen monitoring circuit control circuit. The oxygen content monitoring device 13 is connected to a PLC controller 12 for controlling the nitrogen valve. The nitrogen pipeline is connected to the centrifuge 16 through the nitrogen valve. The mother liquor tank 18 is connected to the oxygen content monitoring device 13 through a gas sampling pipeline 17.

[0022] The mother liquor tank 18 is connected to the waste liquid tank 20 through a balance pipe. The waste liquid tank 20 is connected to the liquid seal tank 21 through a pipeline. The liquid seal tank 21 discharges the tail gas to a collection device.

[0023] The gas sampling pipeline 17 is arranged on the mother liquor tank 18, which can timely and accurately obtain the oxygen content in the centrifuge 16, avoiding misjudgment caused by uneven gas distribution in the centrifuge 16. Nitrogen is introduced from the top of the centrifuge to drive the original gas in the centrifuge into the mother liquor tank 18. When the oxygen content in the mother liquor tank 18 decreases, it means that the oxygen content in the centrifuge 16 has also decreased.

[0024] A balance pipe is provided between the mother liquor tank 18 and the waste liquid tank 20 to prevent the liquid in the mother liquor tank 18 from forming a negative pressure in the mother liquor tank 18 due to pressure changes during the process of flowing to the waste liquid tank 20, thereby sucking in air and affecting the normal use of the oxygen content monitoring device 13.

[0025] The liquid seal tank 21 has the following functions:

[0026] Prevent the centrifuge 16 from forming a micro negative pressure during use and sucking in air from the tail gas end, resulting in an excessive oxygen content and causing the centrifuge 16 to stop.

[0027] The liquid seal tank 21 is filled with liquid, and when the gas flows through, it forms a resistance, making the whole system form a micro positive pressure during the nitrogen filling process to prevent the air in the environment from entering the system.

[0028] The liquid seal tank 21 can visually display whether there is gas flow in the system, and when the system forms a negative pressure, the liquid is sucked into the waste liquid tank 20, so as to timely detect the negative pressure state.

[0029] The oxygen content monitoring device 13 is equipped with an oxygen content probe, which can monitor the change of the oxygen content in the system in real time and give an audible and visual alarm when the oxygen content exceeds the standard.

[0030] Through the feedback signal of the oxygen content value, the PLC controller 12 can control the opening and closing of the nitrogen valve. This system can not only monitor the oxygen content, but also save the nitrogen consumption by intermittently introducing nitrogen.

[0031] The oxygen content monitoring system can monitor the oxygen content all the time. When the oxygen content exceeds the standard, the system will automatically cut off the power supply and stop the operation, thus effectively preventing the occurrence of flash explosion and ensuring the operation safety to the greatest extent.

[0032] Through the above measures, the safety in the production process of the centrifuge can be ensured, the explosion risk caused by static electricity can be reduced, and the precise control of the oxygen content can be achieved.

[0033] Working principle

[0034] A solid-liquid mixture is formed in the reaction kettle 11. The reaction kettle 11 inputs materials to the centrifuge 16 through the material pipeline 14. The centrifuge 16 sends the liquid into the mother liquor tank 18 through centrifugal separation. The mother liquor tank 18 sends the gas into the nitrogen through the gas sampling pipeline 17 for detection by the oxygen content monitoring device 13.

[0035] Nitrogen is supplied to the centrifuge 16 through the oxygen content monitoring device 13. The oxygen content monitoring device 13 is provided with a nitrogen valve, an oxygen content probe and an oxygen monitoring circuit control circuit. The oxygen content monitoring device 13 is connected to the PLC controller 12 for controlling the nitrogen valve. The oxygen content monitoring device 13 controls the nitrogen valve through the controller 12 according to the monitoring results to adjust the oxygen content in the centrifuge 16.

[0036] If the oxygen content is unqualified, the nitrogen valve is opened through the PLC controller 12 to fill nitrogen into the centrifuge 16. The centrifuge 16 is started until the oxygen content in the mother liquor tank 18 reaches the standard. During the operation of the centrifuge 16, if the oxygen content shows an upward trend and reaches the warning value, the nitrogen valve is opened to fill nitrogen. When the nitrogen drops to the safe value, the valve is closed. If the oxygen content continues to rise, the PLC controller 12 will cut off the power supply of the centrifuge 16 and force it to stop.

[0037] The instructions for using the oxygen content monitoring system of the centrifuge are as follows:

[0038] Press Figure 1After the pipeline connection between each part is completed as shown, after the material reaction in the reactor 11 is completed, it is put into the centrifuge 16 through the material pipeline 14. When the centrifuge 16 is started, at this time, the oxygen content monitoring device 13 extracts the gas in the mother liquor tank 18 for detection, detects the oxygen content in the sample gas. If the oxygen content is unqualified, the PLC controls the opening of the nitrogen valve to replace the gas in the centrifuge 16 until the oxygen content is lower than the standard value, and then the centrifuge 16 starts. During the operation, if the oxygen content exceeds the warning value, the device alarms, and at the same time the nitrogen valve opens for replacement until the oxygen content decreases and the alarm disappears. If the nitrogen continuously exceeds the standard value, the PLC controller 12 cuts off the power supply of the centrifuge 16 for shutdown protection. When the oxygen content is lower than a certain value, the nitrogen valve automatically closes. The gas in the mother liquor tank 18 enters the waste liquid tank through the pipeline, and then enters the collection device through liquid sealing of the tank.

[0039] In order to monitor the oxygen content in a timely and accurate manner, refer to Figure 2 This utility model also provides an oxygen monitoring circuit control circuit, which includes a constant potential circuit, a transimpedance amplification circuit and an analog-to-digital conversion module. The constant potential circuit includes a first operational amplifier U3, a PMOS transistor Q4 and an electrochemical sensor Q8 for monitoring oxygen concentration. The electrochemical sensor Q8 is provided with three electrodes C, R and W. C is the reflux electrode, R is the reference electrode, and W is the working electrode. The PMOS transistor Q4 is provided with three electrodes D, S and G. D is the drain electrode, S is the source electrode, and G is the gate electrode.

[0040] The inverting input terminal of the first operational amplifier U3 is connected to the reference electrode of the electrochemical sensor Q8 through a resistor R6. A reference voltage is input to the positive input terminal of the first operational amplifier U3, and the output terminal of the first operational amplifier U3 is connected to the reflux electrode of the electrochemical sensor Q8.

[0041] The working electrode of the electrochemical sensor Q8 is connected to the transimpedance amplification circuit through a load resistor R8. The drain electrode of the PMOS transistor is connected to the reference electrode of the electrochemical sensor Q8, the source electrode of the PMOS transistor is connected to the working electrode of the electrochemical sensor Q8, and the gate electrode of the PMOS transistor is connected to the power supply VCC1.

[0042] A capacitor C3 is connected between the inverting input terminal and the output terminal of the first operational amplifier U3, and a resistor R7 is connected between the reference electrode and the reflux electrode of the electrochemical sensor Q8.

[0043] The power supply terminal of the first operational amplifier U3 is connected to the power supply VCC1, and is grounded respectively through a capacitor C4 and a capacitor C5 for filtering. The negative terminal of the first operational amplifier U3 is grounded.

[0044] Among them, the load resistor R8 and the capacitor of the electrochemical sensor Q8 form an RC circuit, and the root mean square noise and response time are set. The response time is set by selecting different load resistors R8.

[0045] The transimpedance amplifier circuit includes a second operational amplifier U6 and a series voltage dividing circuit. The series voltage dividing circuit includes a resistor R11 and a resistor R12 connected in series. One end of the resistor R11 is connected to the power supply VCC1, one end of the resistor R12 is grounded, and the other ends of the resistor R11 and the resistor R12 are connected to form a voltage dividing node to provide a reference voltage. The voltage dividing node is connected to the non-inverting input terminal of the second operational amplifier U6 through a current limiting resistor R13. The inverting input terminal of the second operational amplifier U6 is connected to the working electrode of the electrochemical sensor Q8 through a load resistor R8. The output terminal of the second operational amplifier U6 is connected to the analog-to-digital conversion module U4 through a resistor R10. The first terminal of the analog-to-digital conversion module U4 is the positive differential analog signal input terminal, the second terminal is the ground terminal, the third terminal is the serial clock terminal, the fourth terminal is the serial data terminal, the fifth terminal is the power supply terminal, and the sixth terminal is the negative differential analog signal input terminal.

[0046] Specifically, the output terminal of the second operational amplifier U6 is connected to the positive differential analog signal input terminal of the analog-to-digital conversion module U4 through a resistor R10. The ground terminal of the analog-to-digital conversion module U4 is grounded. The serial clock terminal and the serial data terminal of the analog-to-digital conversion module U4 are respectively connected to the single-chip microcomputer. The power supply terminal of the analog-to-digital conversion module U4 is connected to the power supply VCC1. The negative differential analog signal input terminal of the analog-to-digital conversion module U4 is connected to the voltage dividing node of the series voltage dividing circuit.

[0047] The advantage of this circuit is that a PMOS transistor Q4 is provided. When the circuit is powered on, the PMOS transistor Q4 is in an open state. When the circuit is powered off, the PMOS transistor Q4 conducts, causing the reference electrode and the working electrode to be short-circuited together. The resistance is very small, about dozens of ohms, quickly short-circuiting the electrochemical sensor Q8, avoiding the accumulation of a large amount of charge on the working electrode and causing polarization. Otherwise, the electrochemical sensor Q8 will take several hours to stabilize when starting up next time.

[0048] The oxygen content monitoring system of a centrifuge provided by the present utility model has the following advantages:

[0049] The gas sampling pipeline is installed on the mother liquor tank, which can timely and accurately obtain the oxygen content in the centrifuge, avoiding misjudgment caused by uneven gas distribution. Nitrogen is introduced from the top of the centrifuge to drive the original gas in the centrifuge into the mother liquor tank. When the oxygen content in the mother liquor tank decreases, the oxygen content in the centrifuge also decreases. A balance pipe is provided between the mother liquor tank and the waste liquid tank to prevent the formation of negative pressure during liquid flow and avoid inhaling air, which affects the normal use of the oxygen content monitoring equipment. The liquid seal tank prevents the formation of a slight negative pressure and the inhalation of air during the operation of the centrifuge, resulting in an excessive oxygen content and causing the shutdown. At the same time, it prevents ambient air from entering the system by forming a slight positive pressure and visually displays the gas flow situation to promptly detect the negative pressure state. The oxygen content monitoring equipment is equipped with an oxygen content probe to monitor the change of oxygen content in real time and give an audible and visual alarm when the standard is exceeded. The PLC controller controls the opening and closing of the nitrogen valve through the feedback signal of the oxygen content value, which can not only monitor the oxygen content but also save nitrogen. The oxygen content monitoring system monitors the oxygen content all the time. When the standard is exceeded, it automatically cuts off the power supply and stops the operation, effectively preventing flash explosion and ensuring the operation safety to the greatest extent. Through these measures, the safety of the centrifuge production process can be ensured, the explosion risk caused by static electricity can be reduced, and the precise control of the oxygen content can be achieved. In addition, by controlling the circuit of the oxygen monitoring circuit, the accumulation of a large amount of charge on the working electrode can be avoided, resulting in polarization phenomenon, so that it can be started quickly and stably next time.

[0050] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A centrifuge oxygen content monitoring system, comprising an oxygen content monitoring device (13), a centrifuge (16), a reactor (11), a mother liquid tank (18), a waste liquid tank (20), a liquid sealing tank (21) and a nitrogen pipeline, characterized in that: The centrifuge (16) is connected to the reactor (11) via a material pipeline (14), the centrifuge (16) is connected to the mother liquid tank (18) via a pipeline, the oxygen content monitoring device (13) is provided with a nitrogen valve, an oxygen content probe and an oxygen monitoring circuit control circuit, the oxygen content monitoring device (13) is connected to a PLC controller (12) for controlling the nitrogen valve, the nitrogen pipeline is connected to the centrifuge (16) via a nitrogen valve, and the mother liquid tank (18) is connected to the oxygen content monitoring device (13) via a gas sampling pipeline (17).

2. The centrifuge oxygen content monitoring system according to claim 1, characterized in that: The mother liquid tank (18) is connected to the waste liquid tank (20) via a balance pipe, the waste liquid tank (20) is connected to the liquid sealing tank (21) via a pipeline, and the liquid sealing tank (21) discharges tail gas to a collection device.

3. The centrifuge oxygen content monitoring system according to claim 2, characterized in that: The oxygen monitoring circuit control circuit comprises a constant potential circuit, a transresistance amplifier circuit and an analog-to-digital conversion module (U4); the constant potential circuit comprises a first operational amplifier (U3), a PMOS tube (Q4) and an electrochemical sensor (Q8) for monitoring oxygen concentration; an inverting input terminal of the first operational amplifier (U3) is connected to a reference electrode of the electrochemical sensor (Q8) through a resistor R6; a reference voltage is input to a positive input terminal of the first operational amplifier (U3); and an output terminal of the first operational amplifier (U3) is connected to a return electrode of the electrochemical sensor (Q8); The working electrode of the electrochemical sensor (Q8) is connected to the transimpedance amplifier circuit through a load resistor R8, the drain of the PMOS tube is connected to the reference electrode of the electrochemical sensor (Q8), the source of the PMOS tube is connected to the working electrode of the electrochemical sensor (Q8), and the gate of the PMOS tube is connected to a power supply VCC1.

4. The centrifuge oxygen content monitoring system according to claim 3, characterized in that: The transimpedance amplifier circuit comprises a second operational amplifier (U6) and a series voltage divider circuit, wherein the series voltage divider circuit comprises a resistor R11 and a resistor R12 connected in series, wherein one end of the resistor R11 is connected to a power supply VCC1, and one end of the resistor R12 is grounded, and the other ends of the resistors R11 and R12 are connected to form a voltage divider node for providing a reference voltage, wherein the voltage divider node is connected to a non-inverting input end of the second operational amplifier (U6) via a current limiting resistor R13, and an inverting input end of the second operational amplifier (U6) is connected to a working pole of an electrochemical sensor (Q8) via a load resistor R8, and an output end of the second operational amplifier (U6) is connected to an analog-to-digital conversion module (U4) via a resistor R10.

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