Fluidized bed particle circulation flow measuring device and method based on Coriolis force

Abstract

The invention discloses a fluidized bed particle circulation flow measuring device based on Coriolis force. The fluidized bed particle circulation flow measuring device comprises a particle circulation measuring tube, an electromagnetic valve, a signal conditioning circuit and a signal collecting and controlling device. The flow tube is composed of a capacitive sensor and a Coriolis flowmeter; an upstream capacitive sensor and a downstream capacitive sensor of the capacitive sensor are respectively positioned at the upper end and the lower end of the flowmeter; the electromagnetic valve is positioned at the lower end of the downstream capacitive sensor to keep the measuring tube full of particulate matters or keep the particulate matters in a high-concentration state; the signal conditioning circuit identifies the capacitance value of the capacitive sensor and transmits the capacitance value to the signal acquisition and control device; the controller calculates the accumulation height of the particles in the measuring tube according to the capacitance value, and issues a control signal to the electromagnetic valve according to the accumulation height, so that the particles in the measuring tube are kept at high concentration. Complex gas-solid two-phase flow is locally converted into single-phase flow or high-particle-concentration fluid easy to measure, and the problem that the circulating flow in the gas-solid circulating fluidized bed is difficult to measure is effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluidized bed particle measurement, in particular to a fluidized bed particle circulation flow measurement device and method based on Coriolis force. BACKGROUND

[0002] Fluidized bed technology is widely used in chemical industry, metallurgy, energy and environment, etc. It is especially useful in the process of efficient contact, reaction and heat exchange between solid particles and gas. The particle circulation flow in the fluidized bed directly affects the reaction efficiency, product quality and energy utilization, so accurate measurement of particle flow is of great significance. By accurately measuring the particle circulation flow, the reaction conditions can be optimized to ensure that the materials are fully mixed and reacted, thereby improving the reaction efficiency. Coriolis flowmeters are widely used in flow measurement due to their high accuracy and non-contact characteristics. When the fluid flows through the vibrating measurement tube, the inertia of the fluid interacts with the vibration of the tube, producing a Coriolis effect. Due to the flow of fluid in the tube and the vibration of the tube itself, the mass and velocity of the fluid will affect the vibration of the tube. The Coriolis force will cause a slight deviation or phase change in the tube, especially in the direction of fluid flow. This deviation or phase change is directly proportional to the mass flow rate of the fluid. The sensor calculates the mass flow rate of the fluid by measuring the phase difference of the tube vibration. In addition, Coriolis flowmeters can also measure the density of the fluid by detecting the change in the vibration frequency of the measurement tube. However, due to the uneven flow of gas-solid two-phase flow and the irregular distribution of particles, the measurement accuracy is reduced. Therefore, the present application combines Coriolis flowmeter with a return pipe concentration feedback adjustment mechanism to convert the difficult-to-measure gas-solid two-phase flow into single-phase flow or high-particle concentration fluid, fully utilizing the precise measurement characteristics of Coriolis flowmeter to achieve accurate measurement of particle flow. SUMMARY

[0003] 1. Technical problems to be solved: In view of the problem that the particle circulation flow in the gas-solid two-phase flow is difficult to accurately measure in the particle measurement process of the circulating fluidized bed, the present application provides a fluidized bed particle circulation flow measurement device and method based on Coriolis force. By controlling the opening of the electromagnetic valve to adjust the particle concentration measured by the capacitive sensor, the complex gas-solid two-phase flow is converted into single-phase flow or high-particle concentration fluid which is easy to measure, and the flow is measured by a high-precision single-straight-tube Coriolis flowmeter, effectively solving the problem of difficult measurement of circulation flow in the gas-solid circulating fluidized bed.

[0004] 2. Technical solutions: A fluidized bed particle circulation flow measurement device based on Coriolis force is applied to gas-solid fluidized bed particle phase flow measurement and control. It includes a particle circulation measurement tube, an electromagnetic valve, a signal conditioning circuit, and a signal acquisition and controller.

[0005] The particle circulation flow pipe is arranged at the lower end of the separator standpipe connected with the fluidized bed return pipe, and is composed of a capacitive sensor and a Coriolis flowmeter; the capacitive sensor is two, which are upstream and downstream capacitive sensors; the upstream and downstream capacitive sensors are respectively located at the upper end and the lower end of the Coriolis flowmeter, and are used for measuring the particle concentration at the upper end and the lower end of the Coriolis flowmeter; the electromagnetic valve is located at the lower end of the downstream capacitive sensor, and the amount of particles remaining in the measuring pipe of the Coriolis flowmeter is controlled by adjusting the opening of the electromagnetic valve, so that the measuring pipe of the Coriolis flowmeter is kept full of particles or the particles are kept in a high concentration state; the signal acquisition and controller receives the collected data of the Coriolis flowmeter and the capacitive sensor, the signal conditioning circuit identifies the capacitance values of the upstream and downstream capacitive sensors, and transmits the identified capacitance values to the signal acquisition and controller; the signal acquisition and controller sends a control signal to the electromagnetic valve according to the particle accumulation height measured by the upstream and downstream capacitive sensors in the measuring pipe of the Coriolis flowmeter, and the electromagnetic valve controls the opening of the electromagnetic valve according to the control signal, so as to keep the particles in the measuring pipe of the Coriolis flowmeter in a high concentration.

[0006] Further, the Coriolis flowmeter includes a measuring pipe, a vibration sensor, an electromagnetic exciter and an outer pipe; the measuring pipe is sleeved to the lower end of the separator standpipe; the vibration sensor and the electromagnetic exciter are fixed to the outer side of the measuring pipe, and the outer pipe is sleeved to the outer side of the vibration sensor and the electromagnetic exciter.

[0007] Further, each capacitive sensor is composed of two arc-shaped electrode pieces, which are symmetrically sleeved to the outer side of the separator return standpipe, and the upstream and downstream capacitive sensors are respectively close to the upper and lower ends of the measuring pipe.

[0008] Further, the Coriolis flowmeter includes a measuring pipe, a vibration sensor, an electromagnetic exciter and an outer pipe; the measuring pipe is sleeved to the lower end of the separator standpipe; the vibration sensor and the electromagnetic exciter are fixed to the outer side of the measuring pipe, and the outer pipe is sleeved to the outer side of the vibration sensor and the electromagnetic exciter.

[0009] Further, the upstream and downstream capacitive sensors are respectively located at the upper end and the lower end of the Coriolis flowmeter, and are used for measuring the particle concentration at the upper end and the lower end of the Coriolis flowmeter, which comprises the following steps: first, calibrate the empty / full pipe of the two capacitive sensors; the empty / full pipe is that the pipe region corresponding to the capacitive sensor is not filled with measured particles or is filled with measured particles; the calibration is to construct the relationship between the measurement capacitance and the accumulation amount of particles in the capacitive sensor according to the capacitance value in the empty pipe or the full pipe; ensure that the downstream capacitive sensor is in the full pipe state, and determine whether the particles are accumulated to the position of the upstream capacitive sensor by judging the height of the particles of the upstream capacitive sensor.

[0010] A measurement method of a fluidized bed particle circulation flow measurement device based on Coriolis force, comprising the following steps: Step one: install the particle circulation measuring tube; calibrate the empty / full tube for the upper and lower capacitive sensors, and obtain the capacitive sensor corresponding to the empty tube region capacitive value C empty , the capacitive sensor corresponding to the full tube region capacitive value C full when the particles fill the capacitive sensor; the particle accumulation height h in the single sensor of the upper and lower capacitive sensors is calculated by the following formula: (1) In the above formula, H is the particle height when the particles fill the capacitive sensor, that is, the axial height of the capacitive sensor electrode; Cm is the capacitive sensor capacitive measurement value.

[0011] Step two: the signal acquisition and controller judges the particle accumulation height in the measuring tube according to the particle height h in the upper and lower capacitive sensors, adjusts the electromagnetic valve opening degree, and keeps the h of the upper capacitive sensor between 0 and the full tube height H; specifically: the initial opening degree of the electromagnetic valve is full opening, when the h of the upper capacitive sensor approaches 0, increase the opening degree of the electromagnetic valve; when the h of the upper capacitive sensor approaches H, reduce the opening degree of the electromagnetic valve; through the control of the opening degree of the electromagnetic valve, keep the material level in the upper capacitive sensor, so that the particles in the measuring tube are close to full and will not accumulate too much to affect the circulation of the particles.

[0012] Step three: the signal acquisition and controller adjusts the frequency of the electromagnetic exciter of the Coriolis flowmeter, measures the amplitude of the vibration sensor at different frequencies to find the resonance frequency corresponding to the maximum amplitude at the current flow.

[0013] Step four: the electromagnetic exciter drives the Coriolis flowmeter measuring tube at the resonance frequency, so that the vibration sensor obtains the strongest vibration signal; the phase difference and frequency signal of the vibration sensor at both ends of the measuring tube are detected to calculate the mass flow and density of the particles, and the measurement results are output and displayed.

[0014] 3. Advantages: (1) The method provides a fluidized bed particle circulation flow measurement device based on Coriolis force, which converts the gas-solid two-phase flow at the vertical pipe position of the material return port in the fluidized bed into single-phase flow or high-concentration gas-solid flow through the electromagnetic valve control, so as to perform more accurate flow measurement. This method adjusts the flow by precisely controlling the electromagnetic valve, so that the particles fill the measuring tube, which provides a guarantee for accurate measurement.

[0015] (2) The method provides a fluidized bed particle circulation flow measuring device based on Coriolis force, a feedback control mechanism of local concentration is established, the capacitance value of particles in the pipe is monitored in real time through a capacitance sensor, and the filling and accumulation state of particles in the flowmeter is judged. The device adjusts the opening degree of the electromagnetic valve according to the particle accumulation signal, keeps the particles full in the whole measuring pipe and stable flow, so that the measurement precision and system stability are improved, and the reliability of the flow measurement under different working conditions is ensured.

[0016] (3) The method provides a fluidized bed particle circulation flow measuring device based on Coriolis force, which can realize accurate control and accurate measurement of particle flow by reasonably arranging the capacitance sensor, the flowmeter and the electromagnetic valve. The capacitance sensor monitors the accumulation state of particles in the pipeline in real time, judges whether the particles are full in the whole pipeline, so as to ensure the accuracy of the flowmeter measurement. The electromagnetic valve adjusts the flow according to the signal feedback by the sensor, keeps the uniform distribution of particles in the pipeline and the stable flow rate, and provides accurate flow control and measurement guarantee for the system.

[0017] (4) The method provides a fluidized bed particle circulation flow measuring device based on Coriolis force, which establishes a relationship function between the capacitance value and the particle accumulation height through the capacitance sensor. The capacitance sensor detects the capacitance value in the pipeline, which indirectly reflects the accumulation height of the medium. Combined with experimental data and fitting algorithm, the relationship model is constructed, which provides accurate basis for subsequent electromagnetic valve adjustment and ensures fine control of the system.

[0018] In summary, the method adopts a double-sensor closed-loop regulation mechanism to convert the gas-solid two-phase flow into high-concentration particle flow or single particle flow in the flowmeter, effectively solves the measurement error problem of the gas-solid two-phase flow, so as to ensure that the Coriolis flowmeter is always in the best working condition and realizes high-precision flow measurement. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a whole structure diagram of the fluidized bed particle circulation flow measuring device based on Coriolis force of the application. Figure 2 It is a schematic diagram of the capacitance sensor involved in the application. Figure 3 It is a control system schematic diagram of the fluidized bed particle circulation flow measuring device based on Coriolis force of the application. Figure 4 It is a control flow chart of the fluidized bed particle circulation flow measuring device based on Coriolis force of the application.

[0020] Figure numerals: 1: lifting pipe; 2: cyclone separator; 3: upstream capacitance sensor; 4: vibration sensor 1; 5: electromagnetic exciter; 6: vibration sensor 2; 7: downstream capacitance sensor; 8: electromagnetic valve; 9: return pipe; 10: air distribution plate; 11: signal acquisition and controller; A1. electrode sheet 1; A2. particulate matter; A3. electrode sheet 2. DETAILED DESCRIPTION

[0021] The present invention will be described in detail below with reference to the accompanying drawings.

[0022] As attached Figure 1 As shown, a fluidized bed particle circulation flow measurement device based on Coriolis force is used for measuring and controlling the particle phase flow in a gas-solid fluidized bed; it is characterized by comprising a particle circulation measurement tube, a solenoid valve, a signal conditioning circuit, and a signal acquisition and controller.

[0023] As attached Figure 3 As shown, the particle circulation flow tube is arranged at the lower end of the separator riser connected to the fluidized bed return port pipe, and is composed of a capacitance sensor and a Coriolis flowmeter. The capacitance sensor is composed of two upstream and downstream capacitance sensors. The upstream and downstream capacitance sensors 3 and 7 are respectively located at the upper and lower ends of the Coriolis flowmeter and are used to measure the particle concentration at the upper and lower ends of the Coriolis flowmeter. The solenoid valve 8 is located at the lower end of the downstream capacitance sensor 7. By adjusting the opening of the solenoid valve, the amount of particles retained in the measuring tube of the Coriolis flowmeter is controlled to keep the measuring tube of the Coriolis flowmeter full of particles or to maintain a high concentration of particles. The signal acquisition and controller receives data collected by the Coriolis flowmeter and the capacitance sensor. The signal conditioning circuit identifies the capacitance values ​​of the upstream and downstream capacitance sensors and transmits the identified capacitance values ​​to the signal acquisition and controller. The signal acquisition and controller sends a control signal to the solenoid valve based on the particle accumulation height in the measuring tube of the Coriolis flowmeter measured by the upstream and downstream capacitance sensors. The solenoid valve controls the opening of the solenoid valve according to the control signal to maintain a high concentration of particles in the measuring tube of the Coriolis flowmeter.

[0024] Furthermore, the Coriolis flowmeter includes a measuring tube, a vibration sensor, an electromagnetic exciter and an outer tube; the measuring tube is sleeved to the lower end of the separator riser; the vibration sensor and the electromagnetic exciter are fixed to the outside of the measuring tube, and the outer tube is sleeved to the outside of the vibration sensor and the electromagnetic exciter.

[0025] Furthermore, as attached Figure 2 As shown, each capacitance sensor is composed of two arc-shaped electrode sheets, which are symmetrically sleeved on the outside of the separator return pipe, and the upstream and downstream capacitance sensors are close to the upper and lower ends of the measuring tube respectively.

[0026] Furthermore, the Coriolis flowmeter has two vibration sensors symmetrically distributed at the upper and lower ends of the measuring tube; and one electromagnetic sensor located in the middle of the measuring tube. Reference numeral 4 represents vibration sensor 1, reference numeral 5 represents electromagnetic exciter, and reference numeral 6 represents vibration sensor 2.

[0027] Furthermore, the upstream and downstream capacitive sensors are respectively located at the upper and lower ends of the Coriolis flowmeter, and are used to measure the particle concentration at the upper and lower ends of the Coriolis flowmeter as follows: first, both capacitive sensors are calibrated for empty / full pipes; the empty / full pipes refer to when there are no measured particles in the pipe area corresponding to the capacitive sensor and when the measured particles fill the pipe area corresponding to the capacitive sensor, and the calibration is to construct a relationship between the measured capacitance and the accumulation amount of particles in the capacitive sensor based on the capacitance value when the pipe is empty or full; ensure that the downstream capacitive sensor is in a full pipe state, and judge whether the particles have accumulated to the position of the upstream capacitive sensor by judging the height of the particles at the upstream capacitive sensor.

[0028] As attached Figure 4 As shown, a measurement method of a fluidized bed particle circulation flow measurement device based on Coriolis force includes the following steps: Step 1: Install the particle circulation measurement tube; calibrate the upper and lower capacitance sensors for empty / full tubes to obtain the capacitance value C of the tube area corresponding to the capacitance sensor when the tube is empty, i.e. when no particles enter the capacitance sensor. empty When the tube is full, that is, when the particles fill the capacitance sensor, the capacitance value C of the area inside the tube corresponding to the capacitance sensor is full. full The particle accumulation height h in a single sensor of the upstream and downstream capacitive sensors is calculated using the following formula: (1) In the above formula, H is the particle height when the particles fill the capacitive sensor, that is, the axial height of the capacitive sensor electrode; Cm is the capacitance measurement value of the capacitive sensor.

[0029] Step 2: The signal acquisition and controller determines the particle accumulation height in the measuring tube according to the particle height h in the upstream and downstream capacitance sensors and adjusts the solenoid valve opening to keep the h of the upper capacitance sensor between 0 and the full tube height H; specifically: the initial opening of the solenoid valve is fully open. When the h of the upper capacitance sensor is close to 0, the solenoid valve opening is increased; when the h of the upper capacitance sensor is close to H, the solenoid valve opening is reduced; through the control of the above-mentioned solenoid valve opening, the material level is maintained in the upstream capacitance sensor, so that the particles are nearly full in the measuring tube and will not accumulate too much to affect the circulation of the particles.

[0030] Step 3: The signal acquisition and controller adjusts the frequency of the electromagnetic exciter of the Coriolis flowmeter, measures the amplitude of the vibration sensor at different frequencies, and finds the resonant frequency corresponding to the maximum amplitude at the current flow rate.

[0031] Step four: the electromagnetic exciter drives the Coriolis flowmeter measuring tube at the resonance frequency so that the vibration sensor obtains the strongest vibration signal; the mass flow and density of the particles are calculated by detecting the phase difference and frequency signal of the vibration sensor at both ends of the measuring tube, and the measurement results are output and displayed. Specific embodiments: As shown in the accompanying Figure 1 In this embodiment, the Coriolis flowmeter uses a single straight tube Coriolis flowmeter. In this embodiment, the particle phase circulation loop of the gas-solid fluidized bed is shown by the arrows in the figure. The gas enters the riser 1 of the circulating fluidized bed from the lower left corner of the air distribution plate 10 upward, part of the gas leaves the fluidized bed from the upper part of the cyclone separator 2, and the particle material flows in the circulating fluidized bed in a clockwise direction.

[0033] The particle circulation flow measurement device provided in this embodiment specifically consists of a particle circulation measurement tube, an electromagnetic valve, a signal conditioning circuit, and a signal acquisition and controller. The particle circulation measurement tube consists of an electrode capacitance sensor and a Coriolis flowmeter. The single straight tube Coriolis flowmeter is installed with an electromagnetic exciter and a vibration sensor. As shown in the accompanying Figure 3 The exciter ensures that the measuring tube maintains a basic vibration state. The electromagnetic valve controls the filling state of the particles in the tube by adjusting the opening size. The capacitance sensor monitors the filling state of the particles in the tube in real time. The vibration sensor monitors the vibration signal (such as vibration frequency, phase difference or time difference) of the measuring tube in real time, which is used to calculate the mass flow of the fluid in the tube. The signal conditioning module is responsible for receiving the signal output by the sensor and processing the original signal. The signal acquisition and controller 11 of the STM32 judges the state of the particles according to the processed signal and displays the measurement results in real time. The feedback control module adjusts the opening of the electromagnetic valve according to the judgment of the data processing module of the STM32, ensures that the particles fill the measuring tube and do not accumulate too much to affect the particle circulation, and thus makes the system run stably.

[0034] The structure of the electrode capacitance sensor in this embodiment is shown in the accompanying Figure 2 Figure 2 ​Fig. (a) is a top view of the capacitive sensor, and Fig. (b) is a three-dimensional view; as shown in Fig. (a), the electrode sheet A1 and A3 are filled with particles A2. The device adopts an external symmetrical electrode structure to form a detection area around the pipeline, and by monitoring the capacitance value between the electrodes, the filling state of the particles in the pipeline corresponding to the detection area is sensed in real time. The particle concentration in the pipeline is determined by monitoring the sensor capacitance, a mapping relationship between the capacitance signal and the particle filling state is established, and it is ensured that the capacitive sensor can accurately sense the accumulation degree of the particles. The electrode capacitive sensor particle concentration measurement system comprises an upstream and a downstream capacitive sensor, and the downstream capacitive sensor continuously monitors the pipeline filling state to ensure that the downstream pipeline always operates at full pipe or maximum particle concentration. At the same time, the upstream capacitive sensor detects the particle concentration change in real time, and when the capacitance value exceeds the preset threshold range, the electromagnetic valve opening degree is automatically adjusted to maintain a stable full pipe or high particle concentration state in the Coriolis flowmeter by dynamically controlling the particle flow in the Coriolis flowmeter. This double-sensor closed-loop control mechanism converts the gas-solid two-phase flow into a high-concentration particle flow or a single particle flow in the flowmeter, effectively solving the measurement error problem of the gas-solid two-phase flow, so as to ensure that the Coriolis flowmeter is always in the best working condition and realizes high-precision flow measurement.

[0035] The measurement process of the embodiment is shown in the accompanying Figure 4 It can be understood that since it is a conventional technique in the art to obtain the gas phase flow velocity by using a Coriolis flowmeter, specific derivation and elaboration will not be performed in this scheme.

[0036] Based on the above embodiment, the present scheme selects the relatively stable return pipe as the fluidized bed circulating flow measurement section, and according to the material level in the fluidized bed return pipe 9 measured by the upper and lower two capacitive sensors, the particle material in the measurement section is kept in a stacked state by adjusting the electromagnetic valve, the complex and variable gas-solid two-phase flow is converted into a single-phase flow or a high-particle-concentration gas-solid flow which is easy to measure, and a mature high-precision single-straight-pipe Coriolis flowmeter is used for flow measurement, thereby simplifying the measurement process and solving the problems of difficult gas-solid two-phase flow measurement and large measurement error.

[0037] The present application uses a capacitive sensor to establish a relationship function between the capacitance value and the particle stacking height. The capacitive sensor indirectly reflects the changes of particle distribution and stacking state by monitoring the capacitance value in the pipeline in real time. Combined with experimental data and fitting algorithm, a correlation model of the capacitance value and the particle stacking amount is constructed, and a feedback control system is established. The closed-loop feedback mechanism not only ensures the stability of the measurement environment, but also effectively avoids the error caused by uneven particle distribution or stacking, thereby significantly improving the accuracy of flow measurement and the overall performance of the system Although the present application has been disclosed in its preferred embodiments with reference to the accompanying drawings, it is not intended to limit the present application thereto, and various changes or modifications can be made thereto by those skilled in the art without departing from the spirit and scope of the present application, and the scope of protection of the present application should be defined by the scope of protection of the claims.

Claims

1. A fluidized bed particle circulation flow measurement device based on Coriolis force, applied to the measurement and control of particle phase flow in a gas-solid fluidized bed; characterized by: It includes a particle circulation measuring tube, a solenoid valve, a signal conditioning circuit, and a signal acquisition and controller; The particle circulation flow measurement tube is arranged at the lower end of the separator riser connected to the fluidized bed return port pipeline, and is composed of a capacitance sensor and a Coriolis flowmeter; the capacitance sensor is composed of two capacitance sensors, one upstream and one downstream; the upstream and downstream capacitance sensors are respectively located at the upper and lower ends of the Coriolis flowmeter, and are used to measure the particle concentration at the upper and lower ends of the Coriolis flowmeter; the solenoid valve is located at the lower end of the downstream capacitance sensor, and controls the amount of particulate matter retained in the Coriolis flowmeter measuring tube by adjusting the opening of the solenoid valve, thereby keeping the Coriolis flowmeter measuring tube full of particulate matter or keeping the particulate matter at a high concentration; the signal acquisition and controller receives the data collected by the Coriolis flowmeter and the capacitance sensor, and the signal conditioning circuit identifies the capacitance values ​​of the upstream and downstream capacitance sensors and transmits the identified capacitance values ​​to the signal acquisition and controller; the signal acquisition and controller sends a control signal to the solenoid valve based on the particle accumulation height in the Coriolis flowmeter measuring tube measured by the upstream and downstream capacitance sensors, and the solenoid valve controls the opening of the solenoid valve based on the control signal to keep the particles in the Coriolis flowmeter measuring tube at a high concentration.

2. The device for measuring the flow rate of fluidized bed particles based on Coriolis force according to claim 1, characterized in that: The Coriolis flowmeter includes a measuring tube, a vibration sensor, an electromagnetic exciter and an outer tube; the measuring tube is sleeved to the lower end of the separator riser; the vibration sensor and the electromagnetic exciter are fixed to the outside of the measuring tube, and the outer tube is sleeved to the outside of the vibration sensor and the electromagnetic exciter.

3. The device for measuring the flow rate of fluidized bed particles based on Coriolis force according to claim 1, characterized in that: Each capacitance sensor is composed of two arc-shaped electrode sheets, which are symmetrically sleeved on the outside of the separator return pipe, and the upstream and downstream capacitance sensors are respectively close to the upper and lower ends of the measuring tube.

4. The device for measuring the flow rate of fluidized bed particles based on Coriolis force according to claim 2, characterized in that: The Coriolis flowmeter has two vibration sensors symmetrically distributed at the upper and lower ends of the measuring tube; and one electromagnetic exciter located in the middle of the measuring tube.

5. The device for measuring the flow rate of fluidized bed particles based on Coriolis force according to claim 1, characterized in that: The upstream and downstream capacitive sensors are respectively located at the upper and lower ends of the Coriolis flowmeter, and are used to measure the particle concentration at the upper and lower ends of the Coriolis flowmeter: first, both capacitive sensors are calibrated for empty / full pipe; the empty / full pipe respectively refers to when the area inside the pipe corresponding to the capacitive sensor is free of measured particles and when the area inside the pipe corresponding to the capacitive sensor is filled with measured particles. The calibration is to establish a relationship between the measured capacitance and the accumulation amount of particles in the capacitive sensor based on the capacitance value when the pipe is empty or full; ensure that the downstream capacitive sensor is in a full pipe state, and determine whether the particles have accumulated to the position of the upstream capacitive sensor by judging the height of the particles at the upstream capacitive sensor.

6. A method for measuring the flow rate of particles circulating in a fluidized bed based on Coriolis force, wherein the method comprises: The following steps are involved: Step 1: Install the particle circulation measurement tube; calibrate the upper and lower capacitance sensors for empty / full tubes to obtain the capacitance value C of the area inside the tube corresponding to the capacitance sensor when the tube is empty, i.e. when no particles enter the capacitance sensor. empty When the tube is full, that is, when the particles fill the capacitance sensor, the capacitance value C of the area inside the tube corresponding to the capacitance sensor is full. full The particle accumulation height h in a single sensor of the upstream and downstream capacitive sensors is calculated using the following formula: （1） In the above formula, H is the particle height when the particles fill the capacitance sensor, that is, the axial height of the capacitance sensor electrode; C m is the capacitance measurement value of the capacitance sensor; Step 2: The signal acquisition and controller determines the particle accumulation height in the measuring tube based on the particle height h in the upstream and downstream capacitance sensors and adjusts the solenoid valve opening to maintain the h of the upper capacitance sensor between 0 and the full tube height H. Specifically, the solenoid valve opening is initially fully open. When the h of the upper capacitance sensor approaches 0, the solenoid valve opening is increased; when the h of the upper capacitance sensor approaches H, the solenoid valve opening is reduced. By controlling the solenoid valve opening, the material level is maintained within the upstream capacitance sensor, so that the particles in the measuring tube are nearly full and do not accumulate excessively to affect the circulation of the particles. Step 3: The signal acquisition and controller adjusts the frequency of the electromagnetic exciter of the Coriolis flowmeter, measures the amplitude of the vibration sensor at different frequencies, and finds the resonant frequency corresponding to the maximum amplitude at the current flow rate; Step 4: The electromagnetic exciter drives the Coriolis flowmeter measuring tube at the resonant frequency so that the vibration sensor can obtain the strongest vibration signal. The mass flow rate and density of the particles are calculated by detecting the phase difference and frequency signal of the vibration sensors at both ends of the measuring tube, and the measurement results are output and displayed.

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