Liquid level control system

Abstract

The utility model discloses a liquid level control system, which comprises a liquid level measuring unit, a liquid level control unit and a discharge valve unit, the liquid level control system is not influenced by pressure, viscosity, color and chemical property when being used for measuring the liquid level of slag, the measuring result is more accurate and reliable, and the liquid level control system is suitable for a gasification furnace for continuously discharging high-temperature slag.

Description

Technical Field

[0001] The utility model relates to the technical field of modern coal chemical industry, in particular to a liquid level control system of a gasifier suitable for continuously discharging high-temperature molten slag. Background Art

[0002] Smokeless lump coal is a high-quality chemical raw material with abundant resources in my country. The smokeless lump coal reactor requires a high pressure of 6.5MPa, a high temperature of 1600-1800℃, and a molten slag temperature maintained at ~1650℃. It has always been a difficult point to achieve accurate measurement and smooth discharge of the slag.

[0003] Conventional contact level meters are difficult to meet this harsh environment and are prone to malfunction; in non-contact level measuring instruments, since there are coal blocks and other mixed gases in the container, they interfere with the signals generated by radar and ultrasound, reducing the accuracy of the instrument's measurement.

[0004] It can be seen that providing a liquid level control system for a gasifier suitable for continuously discharging high-temperature molten slag is a technical problem that needs to be solved urgently by those skilled in the art. Utility Model Content

[0005] The technical problem to be solved by the utility model is to overcome the defects in the prior art and provide a liquid level control system.

[0006] The utility model solves the above technical problems through the following technical solutions:

[0007] A liquid level control system, suitable for a gasifier for continuously discharging high-temperature molten slag, comprising:

[0008] a liquid level measuring unit, installed on the gasifier shell, used to measure the liquid level of the material in the gasifier, the liquid level measuring unit comprising an isotope radiation source, a detector and a signal converter, the detector detects the radiation emitted by the isotope radiation source and indirectly obtains the liquid level signal of the slag, and the signal converter is electrically connected to the detector to convert the liquid level signal into an electrical signal;

[0009] The liquid level control unit comprises an input signal processor, a logic operator and a control output device, wherein the input signal processor is electrically connected to the signal converter and is used to process the electrical signal into a digital signal; the logic operator is electrically connected to the input signal processor and is used to convert the digital signal into a control command signal; the control output device is electrically connected to the logic operator and is used to convert the control command signal into an analog signal;

[0010] The discharge valve unit comprises a pneumatic actuator and a valve, wherein the valve is installed in the discharge channel at the bottom of the gasifier, and the pneumatic actuator is electrically connected to the control output device for receiving and responding to the analog signal to control the opening of the valve.

[0011] Preferably, the discharge valve unit further comprises a solenoid valve, which is electrically connected to the control output device and is used to receive a switching signal sent by the control output device to directly close the valve.

[0012] Preferably, the solenoid valve adopts a double solenoid valve configuration.

[0013] Preferably, the detector and the isotope radiation source are placed facing each other.

[0014] Preferably, the isotope radiation source is a cobalt-60 radiation source.

[0015] Preferably, the isotope radiation source is point-type.

[0016] Preferably, the signal converter and the detector are integrated into one body.

[0017] Preferably, the detector is a scintillation crystal detector.

[0018] Preferably, the valve comprises a valve body and a valve core, the valve body and the valve core are made of ceramic, and the surfaces of the valve body and the valve core that are in contact with the slag are sprayed with high-temperature resistant zirconium oxide.

[0019] Preferably, the valve is a ball valve.

[0020] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present utility model.

[0021] The positive progressive effect of the utility model is that the liquid level control system of the utility model includes a liquid level measuring unit, a liquid level control unit and a discharge valve unit. The liquid level control system of the utility model is not affected by pressure, viscosity, color and chemical properties when measuring the liquid level of the slag material. The measurement result is more accurate and reliable, and can be applied to a gasification furnace that continuously discharges high-temperature slag. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of a liquid level control system according to a preferred embodiment of the utility model.

[0023] Description of reference numerals:

[0024] Isotope Radioactive Sources 101

[0025] Liquid level control unit 102

[0026] Discharge valve unit 103

[0027] Detector 104

[0028] Gasifier 105 DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0030] like Figure 1 As shown, this embodiment discloses a liquid level control system, which can be applicable to a gasifier 105 that continuously discharges high-temperature molten slag, and includes a liquid level measurement unit, a liquid level control unit 102 and a discharge valve unit 103 .

[0031] The liquid level measurement unit is installed on the outer shell of the gasifier 105, and is used to measure the liquid level of the material in the gasifier 105. Specifically, the slag liquid level measurement unit includes an isotope radiation source 101, a detector 104 and a signal converter, the detector 104 is placed opposite to the isotope radiation source 101, the detector 104 is used to detect the intensity of the radiation emitted by the isotope radiation source and calculate the liquid level signal, and the signal converter is electrically connected to the detector 104 to convert the liquid level signal calculated by the signal converter into an electrical signal (such as 4-20mA or a switch alarm signal) and output it to the control room.

[0032] In this embodiment, the isotope radiation source 101 is a point-type cobalt-60 radiation source, but is not limited thereto.

[0033] Gamma rays will attenuate when passing through the material equipment, and the high-sensitivity detector 104 installed on the other side of the equipment can measure the attenuation. Specifically, in this embodiment, the cobalt-60 radiation source emits gamma rays. When the gamma rays pass through the wall of the measured container and the measured material inside and reach the detector 104, the rays are absorbed by the materials of different thicknesses and attenuate. The detector 104 can indirectly obtain the change of the measured material level by detecting the intensity of the attenuated rays to obtain a liquid level signal, and the signal converter converts the liquid level signal into an electrical signal that can be received by the liquid level control unit 102.

[0034] The liquid level control unit 102 includes an input signal processor, a logic operator and a control output device. The input signal processor is electrically connected to the signal converter and is used to process the electrical signal into a digital signal. The logic operator is electrically connected to the input signal processor and is used to convert the digital signal into a control command signal. The control output device is electrically connected to the logic operator and is used to convert the control command signal into an analog signal. Specifically, the input signal processor uses a control system IO card to convert the electrical signal from the signal converter into a digital signal for use by the logic operator. The logic operator uses a programmable logic processor to perform logic operations on the digital signal to obtain a control command signal. The control output device converts the control command signal into an analog signal that can be received by the pneumatic actuator. The liquid level control unit is provided with a human-computer interaction interface, which can display, record, operate and store data.

[0035] The discharge valve unit 103 includes a pneumatic actuator and a valve. The valve is installed in the discharge channel at the bottom of the gasifier 105. The pneumatic actuator is electrically connected to the control output device to receive and respond to analog signals to control the opening of the valve.

[0036] The discharge valve unit 103 also includes a solenoid valve, which is electrically connected to the control output device and is used to receive a switch signal from the control output device to directly close the valve. In this embodiment, the solenoid valve is provided to directly close the valve in an emergency under abnormal circumstances, thereby ensuring the reliability of the control system.

[0037] In addition, in this embodiment, the solenoid valve adopts a double solenoid valve configuration, which further ensures the reliability of the control system.

[0038] Furthermore, in this embodiment, the signal converter is integrated with the detector 104. The integrated design makes the entire detector 104 assembly more compact, reduces space occupation, and facilitates installation and maintenance. It can also reduce external electromagnetic interference to the signal when it is transmitted between the detector 104 and the signal converter, and improve the stability and reliability of the signal.

[0039] In this embodiment, the detector 104 is a scintillation crystal type detector 104 .

[0040] Since the scintillation crystal detector 104 has a high sensitivity to high-energy particles such as gamma rays, it can detect weak radiation signals, and the scintillation crystal detector 104 can quickly respond to incident gamma rays.

[0041] Furthermore, in this embodiment, the valve includes a valve body and a valve core, the valve body and the valve core are made of ceramic, and the surfaces of the valve body and the valve core that are in contact with the slag are sprayed with high-temperature resistant zirconium oxide. Since the temperature of the slag is very high, the valve body and the valve core of the valve are made of ceramic, and the surfaces that are in contact with the slag are sprayed with high-temperature resistant zirconium oxide to ensure the stable operation of the valve in a high-temperature environment.

[0042] Furthermore, in this embodiment, the valve is a ball valve. Since the ball valve has a full-diameter flow channel, the resistance to fluid flow is reduced, thereby improving the efficiency of slag passage, and the ball valve can be opened and closed quickly and can respond quickly.

[0043] In the liquid level control system of this embodiment, the type and geometric shape of the isotope radiation source 101 are constant, so the attenuation of the radiation emitted by the isotope radiation source 101 can only be caused by the change of the slag. The isotope radiation source 101 can cover the entire measurement range. If the material level increases within the radiation range, the radiation attenuates much, and the count rate measured by the detector 104 decreases. Therefore, the liquid level control system of this embodiment is not affected by pressure, viscosity, color and chemical properties for the measurement of the liquid level of the slag material, and the measurement result is more accurate and reliable, and can be applied to the gasification furnace 105 that continuously discharges high-temperature slag.

Claims

1. A liquid level control system, suitable for a gasifier that continuously discharges high-temperature molten slag, characterized in that: include: a liquid level measuring unit, installed on the gasifier shell, used to measure the liquid level of the material in the gasifier, the liquid level measuring unit comprising an isotope radiation source, a detector and a signal converter, the detector detects the radiation emitted by the isotope radiation source and indirectly obtains the liquid level signal of the slag, and the signal converter is electrically connected to the detector to convert the liquid level signal into an electrical signal; The liquid level control unit comprises an input signal processor, a logic operator and a control output device, wherein the input signal processor is electrically connected to the signal converter and is used to process the electrical signal into a digital signal; the logic operator is electrically connected to the input signal processor and is used to convert the digital signal into a control command signal; the control output device is electrically connected to the logic operator and is used to convert the control command signal into an analog signal; The discharge valve unit comprises a pneumatic actuator and a valve, wherein the valve is installed in the discharge channel at the bottom of the gasifier, and the pneumatic actuator is electrically connected to the control output device for receiving and responding to the analog signal to control the opening of the valve.

2. The liquid level control system according to claim 1, characterized in that: The discharge valve unit further comprises a solenoid valve, which is electrically connected to the control output device and is used to receive a switch signal sent by the control output device to directly close the valve.

3. The liquid level control system according to claim 2, characterized in that: The solenoid valve adopts a double solenoid valve configuration.

4. The liquid level control system according to claim 1, characterized in that: The detector is placed facing the isotope radiation source.

5. The liquid level control system according to claim 1, characterized in that: The isotope radiation source is a cobalt-60 radiation source.

6. The liquid level control system according to claim 1, characterized in that: The isotope radiation source is point-type.

7. The liquid level control system according to claim 1, characterized in that: The signal converter is integrated with the detector.

8. The liquid level control system according to claim 1, characterized in that: The detector is a scintillation crystal detector.

9. The liquid level control system according to claim 1, characterized in that: The valve comprises a valve body and a valve core. The valve body and the valve core are made of ceramics. The surfaces of the valve body and the valve core that are in contact with the slag are sprayed with high-temperature resistant zirconium oxide.

10. The liquid level control system according to claim 1, characterized in that: The valve is a ball valve.

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