Pressure vessel liquid level measuring device based on sound wave detection

Abstract

The invention discloses a pressure vessel liquid level measuring device based on sound wave detection, which comprises two sound wave sensors arranged on the outer wall of a vessel at intervals along the height direction of the vessel, the two sound wave sensors are electrically connected with a liquid level transmitter, and the liquid level transmitter is electrically connected with a control system / control center. According to the device, the liquid level is indirectly measured in real time according to the characteristic relation between sound waves generated in the flowing process of a medium in the pressure container and the liquid level of the medium in the container, and the problem that the liquid level of the pressure container is difficult to measure under the severe working conditions such as high temperature, high pressure, strong acid and strong alkali is solved; the influence of the working environment on the liquid level measuring device is greatly reduced, the service life of the liquid level measuring device is prolonged, the cost of the liquid level measuring device can be obviously reduced, the operation is simple, the use is convenient, no additional energy consumption is generated in the operation process, and the liquid level measurement of the pressure vessel is more efficient, reliable, energy-saving and safe.

Description

Technical Field

[0001] The invention relates to a liquid level measuring device, in particular to a pressure vessel liquid level measuring device based on sound wave detection. Background Art

[0002] Automated instruments are the premise of scientific progress and the basis of production activities. When the scope of human activities exceeds the limits of sensory organs, it is necessary to use instrumentation technology to measure and obtain information technology for data information. The automated instrumentation industry is the source of the information industry. In the production process, automated instruments detect, transmit, display, control and execute the information of the measured object, thereby realizing management and decision-making. With the rapid development of the national industry, the requirements for the level and accuracy of automated control in industrial production operations are also rapidly increasing. Liquid level control is an important link in the control of the field of industrial automation. It occupies a pivotal position in many industrial fields and plays an irreplaceable role in ensuring production safety, improving production efficiency, optimizing management decisions, and achieving energy conservation and emission reduction goals. It is mainly reflected in the following aspects: First of all, accurate measurement and control of liquid level is essential to ensure safe and stable operation of the production process. In many industrial processes, such as chemical, petroleum, and pharmaceutical, if the liquid level is too high or too low, it may cause serious accidents such as leakage and explosion. Through accurate liquid level measurement and control, process parameters can be adjusted in time to avoid dangerous situations.

[0003] Secondly, liquid level data is the key basis for optimizing production processes and improving production efficiency. By real-time monitoring of liquid level changes, the feeding and discharging speeds of materials can be accurately controlled, and the production process can be automated and precise, thereby reducing resource waste and improving production efficiency and product quality.

[0004] Furthermore, liquid level data is an important basis for realizing automated production and intelligent management. With the help of real-time data collected by liquid level sensors and related instruments, combined with advanced control systems, automated adjustment and remote monitoring of the production process can be achieved, improving the refinement and intelligence of production management.

[0005] In addition, liquid level information also plays an important role in energy conservation and emission reduction. Reasonable control of liquid level can avoid unnecessary energy consumption and material loss, reduce production costs, and meet the requirements of sustainable development.

[0006] In view of the importance of the above-mentioned liquid level measurement, combined with the difficulties and pain points of liquid level measurement in various sub-sectors of industrial production (such as pressure vessels in special equipment), a liquid level measurement device suitable for actual industrial production and capable of solving liquid level measurement problems encountered in practical applications is developed.

[0007] A pressure vessel refers to a closed device that contains gas or liquid and bears a certain pressure. Pressure vessels are widely used in industrial production, such as non-ferrous metallurgy, petrochemicals, energy, pharmaceuticals and other fields. The liquid level of a pressure vessel is also a very important process parameter during its use, and it plays a vital role in the operation status, equipment safety and production stability of the entire system. In view of the fact that there are harsh environments such as high temperature, high pressure, strong acid and strong alkali inside the pressure vessel, when the direct contact method is used to measure the liquid level, the requirements for the liquid contact material of the instrument are very high. It must not only be resistant to high temperature and high pressure, but also have specific anti-corrosion properties for the corrosive characteristics of the medium in the pressure vessel. Not to mention whether it can be achieved, even if a liquid level detection instrument that can be used in such an application scenario is manufactured, its cost is suddenly increased to a prohibitive level. Therefore, for the detection of pressure vessels, most non-contact measurement methods are used. At present, the commonly used non-contact liquid level measurement instruments for pressure vessels are ultrasonic level gauges, radar level gauges, and nuclear radiation level gauges. Ultrasonic level gauges and radar level gauges use ultrasonic propagation characteristics and microwave radar technology for measurement, while nuclear radiation level gauges use the principle that the intensity of nuclear radiation passing through materials varies with the thickness of the material layer. Ultrasonic level gauges and radar level gauges have certain limitations in applications such as foam, large level fluctuations, high temperature, and high pressure; and nuclear radiation level gauges are not only relatively expensive, but also involve the radioactivity of the source, which must be registered and approved according to laws and regulations. There are also various rules such as the need to wear special protective clothing during use, which makes the cost of use too high, causing many inconveniences. Summary of the invention

[0008] The purpose of the present invention is to provide a pressure vessel liquid level measuring device based on acoustic wave detection, which can effectively and real-timely reflect the pressure vessel liquid level height, and the present invention has a simple and reliable structure and is easy to maintain.

[0009] The technical solution of the present invention is: a pressure vessel liquid level measuring device based on acoustic wave detection, comprising two acoustic wave sensors arranged on the outer wall of the container at intervals along the height direction of the container, the two acoustic wave sensors are electrically connected to the liquid level transmitter through an electrical wiring port, and the liquid level transmitter is electrically connected to the control system / control center.

[0010] In the aforementioned pressure vessel liquid level measuring device based on acoustic wave detection, a sound insulation cover is provided outside each acoustic wave sensor.

[0011] In the aforementioned pressure vessel liquid level measuring device based on acoustic wave detection, the acoustic wave sensor includes an outer shell and a protective structure fixed on the outer wall of the container, and an acoustic sensitive element and a preamplifier are respectively arranged in the inner and outer outer shells and protective structures. The acoustic sensitive element is fixed on the outer wall of the container, and the acoustic sensitive element and the preamplifier are connected via an internal conductive component. The preamplifier is electrically connected to the liquid level transmitter through an electrical wiring port.

[0012] In the aforementioned pressure vessel liquid level measuring device based on acoustic wave detection, two acoustic wave sensors are respectively arranged near the top and bottom positions, one is arranged below the medium low alarm liquid level, and the other is arranged above the medium high alarm liquid level.

[0013] Beneficial effects of the invention: Compared with the prior art, the device of the invention has the following advantages: ① Non-contact measurement of liquid level has a wider range of applications, has no special requirements for the medium itself, and is not affected by high temperature, high pressure and corrosiveness of the medium in the container. It is especially suitable for the situation where the medium in the container coexists with gas / liquid, high temperature, high pressure and corrosiveness; ② The principle and structure should be simple, the components used should be common and universal, and the cost should be low; ③ During the liquid level measurement process, there is no active energy consumption such as radar, sonar, electromagnetic, radiation, etc., and no physical hazards such as electromagnetic radiation and nuclear radiation that are harmful to the human body will be generated. The use cost is low and the safety performance is high; ④ By utilizing the characteristic relationship between the sound waves generated by the medium in the pressure vessel during the flow process and the liquid level of the medium in the container, real-time monitoring with high accuracy can be achieved.

[0014] In summary, the device of the present invention realizes non-contact liquid level measurement based on the characteristic relationship between the sound waves generated by the medium in the pressure vessel during the flow process and the liquid level of the medium in the container. It not only solves the problem that the liquid level of the pressure vessel is difficult to measure under harsh working conditions such as high temperature, high pressure, strong acid, strong alkali, etc., but also greatly reduces the impact of the working environment on the liquid level measuring device, extends the service life of the liquid level measuring device, and can significantly reduce the cost of the liquid level measuring device. It is simple to operate, easy to use, and has no additional energy consumption during the operation process, making the liquid level measurement of the pressure vessel more efficient, reliable, energy-saving and safe. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 This is a schematic diagram of the structure of the acoustic wave sensor.

[0016] Figure numerals: 1-sound wave sensor, 2-soundproof cover, 3-liquid level transmitter, 4-control system / control center, 5-housing and protective structure, 6-sound sensitive element, 7-preamplifier, 8-conductive component, 9-electrical connection port. DETAILED DESCRIPTION

[0017] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0018] An embodiment of the present invention: A pressure vessel liquid level measuring device based on acoustic wave detection includes two acoustic wave sensors 1 arranged on the outer wall of the container at intervals along the height direction of the container. The two acoustic wave sensors 1 are electrically connected to the liquid level transmitter 3 through an electrical wiring port 9, and the liquid level transmitter 3 is further electrically connected to the control system / control center 4.

[0019] The device of the present invention is designed based on the following principle: utilizing the characteristic relationship between the sound waves generated by the medium in the pressure vessel during the flow process and the liquid level of the medium in the container, by detecting the sound waves and comparing with the sound wave frequency-liquid level height characteristic curve table that has been experimentally developed, non-contact real-time monitoring of the liquid level of the medium in the container is achieved during production operation, thereby indirectly measuring the liquid level of the medium in the pressure vessel.

[0020] By arranging two acoustic wave sensors 1 on the side of the pressure vessel (one is arranged below the medium liquid level, and the other is arranged above the medium liquid level, and the specific installation position can be determined according to the heights of the normal liquid level, low alarm liquid level, and high alarm liquid level of the pressure vessel), the acoustic wave sensor 1 measures the acoustic waves generated by the medium in the pressure vessel during the flow process, and transmits the acoustic wave data to the liquid level transmitter 3. The acoustic wave data is automatically matched with the acoustic wave-liquid level standard characteristic curve table that has been experimentally developed in the liquid level transmitter 3, and the two liquid level signals are processed to obtain their weighted average, so as to measure the liquid level of the pressure vessel, realize non-contact real-time monitoring of the liquid level of the medium inside the pressure vessel when the pressure vessel is running, and the liquid level signal can be remotely transmitted to the control system / control center 4.

[0021] The reason why two acoustic wave sensors 1 are needed is that the pressure vessel body is relatively high, the distance is too long, and the height of the medium liquid level in the pressure vessel has an impact on the transmission of sound waves. If you want to ensure high detection accuracy, only one acoustic wave sensor 1 is set, it is necessary to improve the sensitivity and accuracy of the acoustic wave sensor 1, which is costly, and the sensor also has a certain distance requirement for acquiring sound waves. If the number of acoustic wave sensors 1 is increased, the requirements for the acoustic wave sensors 1 will not be harsh, and the acoustic wave frequencies below and above the medium liquid level in the pressure vessel can be measured, so that the applicability and measurement accuracy of the detection device will be better.

[0022] A soundproof cover 2 is disposed outside each acoustic wave sensor 1 to prevent the acoustic waves generated during the flow of the medium inside the pressure vessel from being affected by external environmental noise.

[0023] The acoustic wave sensor 1 includes a shell and a protective structure 5 fixed on the outer wall of the container, and an acoustic sensor 6 and a preamplifier 7 are respectively arranged in the inner and outer shells and the protective structure 5. The acoustic sensor 6 is fixed on the outer wall of the container, and the acoustic sensor 6 and the preamplifier 7 are connected via an internal conductive component 8. The preamplifier 7 is electrically connected to the liquid level transmitter 3 via an electrical wiring port 9. The acoustic waves generated during the flow of the medium inside the pressure vessel are collected by the acoustic sensor 6, and the collected acoustic wave signals are transmitted to the preamplifier 7 via the conductive component 8 for signal processing, and then transmitted to the liquid level transmitter 3.

[0024] The two acoustic wave sensors 1 are respectively arranged near the top and the bottom. By installing the two acoustic wave sensors 1 below and above the liquid level of the medium in the pressure vessel, a high measurement accuracy is ensured.

[0025] The specific implementation features of the present invention are as follows: ① The bottom of the acoustic wave sensor 1 needs to be customized according to the external shape characteristics of the pressure vessel to be installed, ensuring that the bottom is tightly fitted with the outside of the equipment; ② The specific installation positions of the two acoustic wave sensors 1 must be determined according to the heights of the normal liquid level, low alarm liquid level, and high alarm liquid level of the pressure vessel (such as Figure 1 As shown); ③ The liquid level transmitter 3 has the comprehensive functions of filtering out noise sound waves, reading the sound wave frequency corresponding to the liquid level within a specific range, and transmitting the output liquid level; ④ It has standard electronic components 9: the power supply adopts a 24V safety power supply and outputs a 4-20mA standard signal to the outside.

[0026] Taking the flash tank in the dissolution workshop of the Bayer alumina plant as an example, the flash tank is a double elliptical head tank with a diameter of about 5m, a straight section height of about 7m, a working pressure of about 3.4Mpa, and a working temperature of about 270℃. The medium in the tank is red mud slurry, the liquid part is sodium aluminate solution (caustic soda concentration Nk=200~240g / L), and the solid part is red mud, and the two are mixed evenly. The sodium aluminate solution in the flash tank flashes out alkaline vapor, so the container is in a state where gas, liquid and solid coexist. Usually, a nuclear radiation level meter is used for measurement, which is not only expensive, but also requires a nuclear source to be set up due to the presence of nuclear radiation. In order to ensure safety, the operation is complicated and the approval procedures are cumbersome. After the liquid level measurement device is set up, the real-time liquid level measurement function can be realized, the measurement accuracy reaches ±5%, and it is low in price, easy to operate and safe.

Claims

1. A pressure vessel liquid level measuring device based on acoustic wave detection, characterized in that: The invention comprises two acoustic wave sensors (1) arranged on the outer wall of the container at intervals along the height direction thereof. The two acoustic wave sensors (1) are electrically connected to a liquid level transmitter (3) via an electrical wiring port (9), and the liquid level transmitter (3) is further electrically connected to a control system / control center (4).

2. A pressure vessel liquid level measuring device based on acoustic wave detection according to claim 1, characterized in that: A sound insulation cover (2) is arranged outside each sound wave sensor (1).

3. The pressure vessel liquid level measuring device based on acoustic wave detection according to claim 1 is characterized in that: The acoustic wave sensor (1) comprises a shell and a protective structure (5) fixed on the outer wall of a container, wherein an acoustic sensor (6) and a preamplifier (7) are respectively arranged in the inner and outer shells and the protective structure (5), wherein the acoustic sensor (6) is fixed on the outer wall of the container, the acoustic sensor (6) and the preamplifier (7) are connected via an internal conductive component (8), and the preamplifier (7) is electrically connected to a liquid level transmitter (3) via an electrical connection port (9).

4. The pressure vessel liquid level measuring device based on acoustic wave detection according to claim 1, characterized in that: Two acoustic wave sensors (1) are respectively arranged near the top and bottom positions, one is arranged below the medium low alarm liquid level, and the other is arranged above the medium high alarm liquid level.

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