Fenton fluidized bed and its internal bed expansion height measurement, control method

Abstract

The application discloses a Fenton fluidized bed and a method for measuring and controlling the expansion height of the internal bed layer of the Fenton fluidized bed. The Fenton fluidized bed comprises a fluidized bed body and a sensor assembly. The fluidized bed body is provided with a granular bed layer. The sensor assembly comprises a first sensor in a fluidized zone, a second sensor at a designed expansion height and a third sensor in a water zone. The sensor assembly is used for measuring the expansion height of the granular bed layer. In the application, the sensors at different heights are arranged in the fluidized bed body to form the sensor assembly. When the second sensor detects that the flow direction is downward, the expansion height of the granular bed layer reaches the designed expansion height. When the third sensor detects that the flow direction is downward, the expansion height of the granular bed layer reaches the maximum allowable height. An analog-digital converter is arranged to generate a preparation signal and a flip signal. The preparation signal and the flip signal are compared during the operation process, double judgment is performed, and unstable jumping of the output signal at the junction of the fluidized zone and the water zone is avoided.

Description

Technical Field

[0001] This application relates to the field of fluidized bed technology, and in particular to a Fenton fluidized bed and a method for measuring and controlling the expansion height of the internal bed layers. Background Technology

[0002] Fluidized bed Fenton oxidation tower technology is widely used in the pretreatment and advanced treatment stages of wastewater in various industries. The Fenton fluidized bed tower contains particulate carriers. When solid particles come into contact with the fluid, they are suspended in the moving fluid or move with it under the influence of the fluid; this phenomenon is called fluidization. When the flow velocity increases to near the minimum fluidization velocity (µmf), the bed particles begin to loosen, and the bed height begins to increase slightly. As the fluid velocity continues to increase, the bed height increases significantly, resulting in bed expansion. A suitable bed expansion height is a crucial indicator for the normal and efficient operation of the Fenton fluidized bed.

[0003] Currently, the Richardson-Zaki empirical correlation (ul / ui = εn) and its modified form are commonly used to describe the particle bed expansion characteristics in solid-liquid fluidized beds, both domestically and internationally. Using this method, firstly, the expansion exponent n and the terminal settling velocity ui of the particles in the Richardson-Zaki equation need to be determined under a given apparent liquid velocity ul; secondly, the average porosity ε of the liquid-solid fluidized bed is calculated using the Richardson-Zaki equation; then, the bed expansion rate or bed expansion height under the apparent velocity ul condition is further calculated using the average porosity ε of the fluidized bed. This method is not only cumbersome but also suffers from the problem of accurately determining the expansion exponent n and the terminal settling velocity ui.

[0004] In many cases, a number of observation ports are opened in the tower wall, and the position of the bed layer is observed manually at regular intervals. There is no light source inside the tower, making observation difficult, prone to deviation, and requiring high labor costs. It is also impossible to monitor the height of the bed layer in real time or achieve automated control. Summary of the Invention

[0005] To solve at least one of the above-mentioned technical problems, this application provides a Fenton fluidized bed and a method for measuring and controlling the expansion height of the internal bed layers. The technical solution adopted is as follows:

[0006] This application provides a Fenton fluidized bed, which includes a fluidized bed body and a sensor assembly. The fluidized bed body has an inlet at the bottom and an outlet at the top. A particle bed is disposed within the fluidized bed body, which defines a fluidization zone and a water zone at the top of the fluidization zone. Water can enter the fluidized bed body through the inlet, pass through the particle bed, and flow out of the fluidized bed body through the outlet. The sensor assembly is disposed on the inner wall of the fluidized bed body and includes at least three sensors: a first sensor located in the fluidization zone, a second sensor located at the designed expansion height, and a third sensor located in the water zone. The sensor assembly is used to measure the expansion height of the particle bed.

[0007] In some embodiments of this application, the first sensor, the second sensor, and the third sensor all include a deformable plate, which is disposed on the inner wall of the fluidized bed body. The deformable plate is inclined and extends toward the bottom of the fluidized bed body.

[0008] The fluid flow direction in the fluidized zone is different from that in the water zone, and the deformable plate can deform in different directions in the fluidized zone and the water zone.

[0009] In some embodiments of this application, the first sensor, the second sensor, and the third sensor all include a protective housing. The protective housing is disposed on the inner wall of the fluidized bed body, and the protective housing and the inner wall of the fluidized bed body form an isolation space. The portion of the deformable plate connected to the inner wall of the fluidized bed body is located within the isolation space.

[0010] In some embodiments of this application, the end of the deformable plate away from the inner wall of the fluidized bed body extends out of the isolation space, and a flexible sealing structure is provided at the position where the deformable plate contacts the protective shell, so as to flexibly connect the deformable plate and the protective shell.

[0011] In some embodiments of this application, strain structures are provided on both opposite sides of the deformable plate. When the deformable plate deforms, the strain structures are subjected to tensile or compressive forces, thereby increasing or decreasing the resistance of the strain structures.

[0012] This application provides a method for measuring and controlling the bed expansion height inside a Fenton fluidized bed. The method for measuring and controlling the bed expansion height inside a Fenton fluidized bed includes:

[0013] Water is introduced into the fluidized bed body through the inlet and discharged from the outlet.

[0014] In the fluidized zone, the water flow and the particle structure in the particle bed flow upward in the central region, forming vortices around the central region, and downward in the region near the inner wall of the fluidized bed body; in the water zone, the water flow is upward.

[0015] When the sensor detects that the surrounding fluid is flowing downwards, the sensor is currently in the fluidized zone or the particle bed expansion height has reached the sensor height; when the sensor detects that the surrounding fluid is flowing upwards, the sensor is currently in the water zone or the particle bed expansion height has not reached the sensor height.

[0016] Connect the sensor to a detection circuit that includes a resistor to obtain the detection voltage E0;

[0017] The detected voltage is input to the analog-to-digital converter (ADC). The ADC obtains a ready signal and a flip signal by comparing the voltages. Based on the dual judgment of the ready signal and the flip signal, the output digital signal is obtained.

[0018] The analog-to-digital converter determines the expansion height by outputting a digital signal, and then quantitatively adjusts the water flow rate based on the deviation between the expansion height and the design height.

[0019] In some embodiments of this application, when the sensor detects that the surrounding fluid is flowing downwards, the current sensor is in the fluidized zone or the particle bed expansion height reaches the sensor height; when the sensor detects that the surrounding fluid is flowing upwards, the current sensor is in the water zone or the particle bed expansion height has not reached the sensor height, including:

[0020] A deformation plate with strain structures on both the top and bottom sides is set as part of the sensor.

[0021] When the fluid around the sensor flows downwards, the deformable plate bends downwards. The strain structure at the top of the deformable plate is under tension, and its resistance increases; the strain structure at the bottom of the deformable plate is under compression, and its resistance decreases.

[0022] When the fluid around the sensor flows upward, the deformation plate bends upward. The strain structure at the top of the deformation plate is compressed, and its resistance decreases. The strain structure at the bottom of the deformation plate is stretched, and its resistance increases.

[0023] In some embodiments of this application, connecting the sensor to a detection circuit including a resistor to obtain a detection voltage includes:

[0024] The detection circuit includes both adjustable and fixed resistors.

[0025] Before testing, adjust the adjustable resistor according to the initial deformation of the sensor to bring the output voltage to zero.

[0026] In some embodiments of this application, the step of inputting the detected voltage into the analog-to-digital converter (ADC), and the ADC obtaining a preparation signal and a toggle signal by comparing the voltages, includes:

[0027] The initial stage digital signals of the analog-to-digital converter, which includes the first comparator, the second comparator, and the third comparator, are all set to 1. A first switching voltage E+ is set on the second comparator, and a second switching voltage E- is set on the third comparator.

[0028] The detection voltage is input to the first comparator. When the detection voltage is positive, the preparation signal is set to 1. The detection voltage is input to the second comparator. When the detection voltage is greater than the first flip voltage, the flip signal is set to 1. When the detection voltage is less than the first flip voltage, the flip signal is set to 0.

[0029] When the detected voltage is negative, the preparation signal is set to 0. The detected voltage is input to the third comparator. When the detected voltage is less than the second flip voltage, the flip signal is set to 0. When the detected voltage is greater than the second flip voltage, the flip signal is set to 1.

[0030] In some embodiments of this application, a fourth comparator and a fifth comparator are provided in the analog-to-digital converter;

[0031] When the detected voltage is positive, the preparation signal and the flip signal are input to the fourth comparator. When both the preparation signal and the flip signal are 1, the output digital signal is 1; when the preparation signal and the flip signal are different, the output digital signal of the previous moment is maintained.

[0032] When the detected voltage is negative, the preparation signal and the flip signal are input to the fifth comparator. When both the preparation signal and the flip signal are 0, the output digital signal is 0; when the preparation signal and the flip signal are different, the output digital signal of the previous moment is maintained.

[0033] The embodiments of this application have at least the following beneficial effects: In this application, sensors at different heights are set in the fluidized bed body to form a sensor assembly; the sensor assembly includes at least a first sensor in the fluidized zone, a second sensor at the designed expansion height, and a third sensor in the water zone. Since each sensor is located on the inner wall of the fluidized bed body, the fluid flow direction is opposite in the fluidized zone and the water zone near the inner wall of the fluidized bed body. Under normal operation, the first sensor detects a downward flow direction, and the third sensor detects an upward flow direction. When the second sensor detects a downward flow direction, the expansion height of the particle bed reaches the designed expansion height; when the third sensor detects a downward flow direction, the expansion height of the particle bed reaches the maximum allowable height, thereby realizing automated detection of the expansion height; by setting an analog-to-digital converter, a preparation signal and a reversal signal are generated. During operation, the preparation signal and the reversal signal are compared for double judgment, and the final output signal is obtained, avoiding unstable fluctuations in the output signal at the junction of the fluidized zone and the water zone, which would affect the judgment.

[0034] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0035] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0036] Figure 1 This is a cross-sectional view of the Fenton fluidized bed in this application;

[0037] Figure 2 This is a side view of each sensor in the Fenton fluidized bed of this application;

[0038] Figure 3 This is a cross-sectional view of each sensor in the Fenton fluidized bed of this application;

[0039] Figure 4 This is a partial enlarged view of each sensor in the Fenton fluidized bed of this application;

[0040] Figure 5 This is a fluid flow diagram of the fluidization zone and the water zone in the method for measuring and controlling the bed expansion height inside the Fenton fluidized bed of this application;

[0041] Figure 6 This is a schematic diagram of the detection circuit in the method for measuring and controlling the expansion height of the internal bed layer in the Fenton fluidized bed of this application;

[0042] Figure 7 This is a schematic diagram of the internal structure of the analog-to-digital converter in the method for measuring and controlling the bed expansion height inside the Fenton fluidized bed of this application;

[0043] Figure 8 This is a diagram of the analog signal of the detection voltage in the method for measuring and controlling the expansion height of the bed inside the Fenton fluidized bed in this application;

[0044] Figure 9 This application relates to the method for measuring and controlling the bed expansion height inside the Fenton fluidized bed. Figure 8 The corresponding output digital signal.

[0045] Figure label:

[0046] Fluidized bed body 101; Fluidized zone 102; Water zone 103;

[0047] First sensor 201; Second sensor 202; Third sensor 203;

[0048] Deformable plate 301; protective shell 302; isolation space 303; flexible sealing structure 304; strain structure 305;

[0049] Adjustable resistor 401; Fixed resistor 402; Detection voltage 403;

[0050] First comparator 501; Second comparator 502; Third comparator 503; First flip voltage 504; Second flip voltage 505; Zero voltage 506; Ready signal 507; Flip signal 508; Fourth comparator 509; Fifth comparator 510; Output digital signal 511. Detailed Implementation

[0051] This section will combine Figures 1 to 9 The embodiments of this application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0052] In the description of this application, it should be understood that the use of terms such as "center," "middle," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" to indicate orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings is solely for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Features defined with "first" and "second" are used to distinguish feature names and do not have special meanings. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0053] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0054] In fluidized beds, the expansion height of the particle bed is a crucial parameter guiding engineering design and the selection of operating conditions. An excessively high expansion height will cause particles to flow out from the top outlet and waste energy in the circulating pump, while an excessively low expansion height indicates poor fluidization and is detrimental to the reaction. Therefore, it is necessary to accurately measure the expansion height and control it within the set value.

[0055] In most cases, a number of observation ports are opened on the tower wall, and the position of the bed is observed manually at regular intervals to detect the expansion height of the particle bed. There is no light source inside the tower, making observation difficult and prone to deviation. It also requires labor costs, cannot monitor the bed height in real time, and cannot achieve automated control.

[0056] like Figure 1 As shown, this application embodiment provides a Fenton fluidized bed, which includes a fluidized bed body 101 and a sensor assembly.

[0057] The fluidized bed body 101 is generally formed into a cylindrical structure, and the internal space of the fluidized bed body 101 is used to contain water and the bed layer. In order to facilitate the introduction and removal of water, the fluidized bed body 101 is provided with an inlet and an outlet. It can be understood that both the inlet and the outlet are connected to the internal space of the fluidized bed body 101.

[0058] Furthermore, the inlet is located at the bottom of the fluidized bed body 101, and the outlet is located at the top of the fluidized bed body 101. Water enters the internal space of the fluidized bed body 101 from the bottom, and the water entering the internal space exits from the top. Specifically, two inlets are provided, one for introducing iron ions and the other for introducing hydrogen peroxide.

[0059] The fluidized bed body 101 contains a number of granular structures, forming a bed layer, known as the granular bed. Specifically, the granular structures are made of quartz sand particles with a diameter of 0.3 mm to 1.5 mm. When water is introduced into the fluidized bed body 101, the granular structures are subjected to the water flow, resulting in a fluidized state.

[0060] Meanwhile, the particle bed defines a fluidization zone 102 and a water zone 103 within the fluidized bed body 101. The space within the fluidized bed body 101 that accommodates the particle bed is the fluidization zone 102, and the water zone 103 is located at the top of the fluidization zone 102 to hold water. Therefore, the water flow process is as follows: it enters the fluidized bed body 101 through the inlet, and as the liquid level rises, the water flows through the fluidization zone 102 defined by the particle bed, then through the water zone 103, and finally flows out of the fluidized bed body 101 through the outlet.

[0061] In addition, to ensure that water can be injected into the fluidized bed body 101 at a certain pressure, a support plate is provided inside the fluidized bed body 101, and the particle bed is located on top of the support plate. A water distribution head is provided on the support plate, and a pipe connected to the water inlet is provided on the water distribution head. Water reaches the water distribution head along the pipe and is injected into the particle bed through the water distribution head.

[0062] A sensor assembly is installed inside the fluidized bed body 101. The sensor assembly is the core component for detecting the bed expansion height and includes several independent sensors. Furthermore, the sensor assembly is located on the inner wall of the fluidized bed body 101 to facilitate contact with the fluid inside the fluidized bed body 101.

[0063] The granular bed has a suitable designed expansion height. When the actual expansion height is close to the designed expansion height, it can effectively perform fluidization. At the same time, the granular bed also has a maximum expansion height. When the actual expansion height exceeds the maximum expansion height, the granular structure is prone to flowing out of the outlet, which can also lead to energy waste in the pump.

[0064] Therefore, by designing a second sensor 202 at the expansion height and a third sensor 203 at the maximum expansion height, it can be understood that the third sensor 203 is located within the water zone 103. When the expansion height reaches the second sensor 202 or the third sensor 203, the second sensor 202 or the third sensor 203 can emit a specific voltage signal to guide the pump's water flow adjustment.

[0065] Specifically, to ensure comprehensive measurement, the sensor assembly also includes a first sensor 201 disposed within the fluidization zone 102. It is understood that the sensor assembly includes at least the three sensors described above, and more than three sensors can be used when improved measurement accuracy is required. In some examples, four sensors are used, with two of the first sensors 201 located within the fluidization zone 102.

[0066] like Figure 2 As shown, in some examples, the first sensor 201, the second sensor 202 and the third sensor 203 adopt approximately the same structure, all including the deformable plate 301.

[0067] Furthermore, the fixed end of the deformation plate 301 is disposed on the inner wall of the fluidized bed body 101, and the free end extends into the internal space of the fluidized bed body 101, so that the deformation plate 301 can detect the expansion height of the bed by means of free end deformation.

[0068] The deformable plate 301 is inclined, meaning the height of its fixed end is greater than the height of its free end, and the free end of the deformable plate 301 extends towards the bottom of the fluidized bed body 101. This inclined arrangement of the deformable plate 301 facilitates the natural sliding of particles contacting it, preventing particle accumulation on the deformable plate 301.

[0069] Specifically, the deformation plate 301 has a length of 100mm to 300mm, a width of 50mm to 100mm, and a thickness of 5mm to 20mm. The deformation plate 301 is made of carbon steel or other wear-resistant metals, or it can be made of plastic, with a Young's modulus of 1GPa to 200GPa. Furthermore, the fixed end of the deformation plate 301 is connected to the inner wall of the fluidized bed body 101 by welding or fasteners, forming an angle of 30° to 60° with the inner wall of the fluidized bed body 101.

[0070] like Figure 3 As shown, in some examples, the first sensor 201, the second sensor 202 and the third sensor 203 all include a protective housing 302. The protective housing 302 is used to protect the connection between the deformable plate 301 and the inner wall of the fluidized bed body 101, so as to avoid the decrease in detection accuracy caused by the obstruction of the connection.

[0071] The protective shell 302 and the inner wall of the fluidized bed body 101 form an isolation space 303, and the connection position between the deformable plate 301 and the inner wall of the fluidized bed body 101 is located within the isolation space 303.

[0072] It is understandable that the free end of the deformable plate 301 needs to be outside the isolation space 303 to contact the fluid inside the fluidized bed body 101, so the free end of the deformable plate 301 extends out of the isolation space 303.

[0073] Specifically, the protective shell 302 is made of carbon steel or other wear-resistant materials and is welded or connected to the inner wall of the fluidized bed body 101 by fasteners.

[0074] In some examples, a flexible sealing structure 304 is provided at the location where the deformable plate 301 contacts the protective shell 302, i.e., where the deformable plate 301 passes through the protective shell 302. The flexible sealing structure 304, on the one hand, makes the isolation space 303 a relatively closed space, preventing external water or particulate matter from entering the isolation space 303. On the other hand, the constraint force exerted by the flexible sealing structure 304 on the deformable plate 301 is negligible, allowing the deformable plate 301 to be in a state of near-free deformation, ensuring the accuracy of the detection. Specifically, the flexible sealing structure 304 is made of wear-resistant and waterproof rubber or resin material.

[0075] like Figure 4 As shown, in some examples, strain structures 305 are provided on both opposite sides of the deformable plate 301 to detect its deformation. Specifically, the strain structures 305 are located on the top and bottom surfaces of the deformable plate 301, respectively, to facilitate the reflection of the stress on the deformable plate 301. When the deformable plate 301 is subjected to an upward or downward force, the strain structure 305 on one side experiences tensile force, increasing its resistance; the strain structure on the other side experiences compressive force, decreasing its resistance. In the circuit, the change in resistance of the strain structure 305 can be expressed in the form of a detection voltage 403, denoted as E0.

[0076] This application provides a method for measuring and controlling the bed expansion height inside a Fenton fluidized bed, including:

[0077] Step S100: Water is introduced into the fluidized bed body from the inlet and discharged from the outlet.

[0078] The water pump first introduces water at a preset flow rate through the inlet at the bottom of the fluidized bed body 101. The water travels along the pipeline to the water distribution head, and then is sprayed into the fluidization zone 102 from the water distribution head. As the liquid level rises, the water reaches the water zone 103, and is then discharged from the fluidized bed body 101 through the outlet in the water zone 103. During the water introduction process, the particle bed in the fluidization zone 102 undergoes fluidization.

[0079] In step S200, in the fluidized zone, the water flow and the particle structure in the particle bed flow upward in the central region, and vortices are formed around the central region. In the region near the inner wall of the fluidized bed body, the flow is downward. In the water zone, the water flow is upward.

[0080] like Figure 5 As shown, during the upward flow of water, it is affected by the particle bed. Under the influence of the particle bed, the water in fluidized zone 102 mainly flows upward along the central area of ​​fluidized zone 102, thus entering water zone 103. During its journey through the central area, the water gradually diverts to the periphery. As the water flows around the central area, its flow direction bends, forming several longitudinal vortices. The vortices near the central area exhibit an upward flow direction, while those near the inner wall of the fluidized bed body 101 exhibit a downward flow direction. Simultaneously, since each sensor is located on the inner wall of the fluidized bed body 101, if a sensor is located within fluidized zone 102, the sensor will detect a downward flow direction in the surrounding fluid.

[0081] Once the water reaches water zone 103, it is no longer affected by the particle bed. Therefore, the water flow at all locations in water zone 103 is upward. This means that the water flow near the inner wall of the fluidized bed body 101 is also upward. Thus, if the sensor is located within water zone 103, the sensor will detect an upward flow of the surrounding fluid.

[0082] In step S300, when the sensor detects that the flow direction of the surrounding fluid is downward, the current sensor is in the fluidized zone or the expansion height of the particle bed has reached the height of the sensor; when the sensor detects that the flow direction of the surrounding fluid is upward, the current sensor is in the water zone or the expansion height of the particle bed has not reached the height of the sensor.

[0083] The height of the boundary between water zone 103 and fluidized zone 102 is the bed expansion height. If a sensor at the designed expansion height detects that the surrounding fluid flow direction is upward, then the sensor is in water zone 103, meaning that the current bed expansion height has not yet reached the designed expansion height. If a sensor at the designed expansion height detects that the surrounding fluid flow direction is downward, then the sensor is in fluidized zone 102, meaning that the current bed expansion height has exceeded the designed expansion height. This method is used to detect whether the current expansion height meets the standard.

[0084] In step S400, the sensor is connected to a detection circuit including a resistor to obtain the detection voltage.

[0085] like Figure 6As shown, each sensor is housed in a corresponding detection circuit, and the two strain gauges 305 of the sensor are located within the detection circuit. When the strain gauges of the sensor detect the flow direction of the surrounding fluid, the resistance of the strain gauges changes, thereby affecting the detection voltage 403, or E0, output by the detection circuit. At this time, the detection voltage 403 can reflect the flow direction of the fluid around the sensor, and thus determine whether the expansion height has reached the current sensor height.

[0086] In step S500, the detected voltage is input to the analog-to-digital converter. The analog-to-digital converter obtains a preparation signal and a flip signal by comparing the voltages. Under the dual judgment of the preparation signal and the flip signal, the output digital signal is obtained.

[0087] like Figure 7 As shown, each sensor is equipped with an analog-to-digital converter (ADC). The detected voltage 403 generates a preparation signal 507 and a flip signal 508 within the ADC, both of which are digital signals. The ADC performs a comprehensive judgment based on the preparation signal 507 and the flip signal 508 to obtain an output digital signal 511. This avoids output fluctuations in sensors located at the boundary between the fluidization zone 102 and the water zone 103, which could make it difficult to determine whether the expansion height has reached the current sensor height.

[0088] In step S600, the analog-to-digital converter determines the expansion height by outputting a digital signal, and quantitatively adjusts the water flow rate based on the deviation between the expansion height and the design height.

[0089] By analyzing the digital signals 511 output from various sensor locations, the expansion height can be determined. This expansion height is then compared to the design height, and the pump flow rate is quantitatively adjusted based on the deviation. If the expansion height is higher than the design height, the flow rate is reduced; if the expansion height is lower than the design height, the flow rate is increased, thus achieving automatic adjustment of the expansion height.

[0090] In another embodiment, step S300 may include, but is not limited to, the following steps:

[0091] Step S310: Set a deformation plate with strain structures on both the upper and lower sides as part of the sensor;

[0092] In step S320, when the fluid around the sensor flows downward, the deformation plate bends downward, the strain structure at the top of the deformation plate is under tension and its resistance increases; the strain structure at the bottom of the deformation plate is under compression and its resistance decreases.

[0093] In step S330, when the fluid around the sensor flows upward, the deformation plate bends upward, the strain structure at the top of the deformation plate is compressed and its resistance decreases, and the strain structure at the bottom of the deformation plate is stretched and its resistance increases.

[0094] The deformation plate 301 has strain structures 305 on both its upper and lower sides. When subjected to tensile and compressive forces, the strain structures 305 can produce opposite resistance changes. Since the strain structures 305 are connected in the detection circuit, the change in resistance causes the detection voltage 403 to change as well.

[0095] Specifically, when the strain structure 305 is subjected to tensile force, the resistance of the strain structure 305 increases; when the strain structure 305 is subjected to compressive force, the resistance of the strain structure 305 decreases.

[0096] It is understandable that when the surrounding fluid flows downward, it applies a downward force to the deformable plate 301, causing the deformable plate 301 to deform accordingly. As a result, the strain structure 305 at the top of the deformable plate 301 is under tension, and its resistance increases. The strain structure 305 at the bottom of the deformable plate 301 is under compression, and its resistance decreases.

[0097] When the surrounding fluid flows upward, it applies an upward force to the deformable plate 301, causing the deformable plate 301 to deform accordingly. As a result, the strain structure 305 at the top of the deformable plate 301 is compressed, and its resistance decreases. Meanwhile, the strain structure 305 at the bottom of the deformable plate 301 is stretched, and its resistance increases.

[0098] In another embodiment, step S400 may include, but is not limited to, the following steps:

[0099] Step S410: Set an adjustable resistor and a fixed resistor in the detection circuit;

[0100] Step S420: Before detection, adjust the adjustable resistor according to the initial deformation of the sensor to bring the output voltage to zero.

[0101] The detection circuit includes two strain structures 305 of the current sensor, a fixed resistor 402, an adjustable resistor 401, and an excitation power supply. The excitation power supply provides a constant voltage to the detection circuit, and the detection voltage 403 is the voltage between the fixed resistor 402 and the adjustable resistor 401.

[0102] During sensor installation, certain errors may occur, causing the sensor's deformation plate 301 to deform in its initial state, affecting detection accuracy. Before detection, the output voltage is adjusted to zero by adjusting the adjustable resistor 401 to balance this error.

[0103] In another embodiment, step S500 may include, but is not limited to, the following steps:

[0104] Step S510: Set the initial stage digital signals of the analog-to-digital converter, which includes the first comparator, the second comparator, and the third comparator, to 1; set the first switching voltage E+ on the second comparator; and set the second switching voltage E- on the third comparator.

[0105] Step S520: The detection voltage is input to the first comparator. When the detection voltage is positive, the preparation signal is set to 1. The detection voltage is input to the second comparator. When the detection voltage is greater than the first flip voltage, the flip signal is set to 1. When the detection voltage is less than the first flip voltage, the flip signal is set to 0.

[0106] Step S530: When the detected voltage is negative, the preparation signal is set to 0. The detected voltage is input to the third comparator. When the detected voltage is less than the second flip voltage, the flip signal is set to 0. When the detected voltage is greater than the second flip voltage, the flip signal is set to 1.

[0107] Step S540: Configure the fourth and fifth comparators in the analog-to-digital converter;

[0108] Step S550: If the detected voltage is positive, input the preparation signal and the flip signal into the fourth comparator. When both the preparation signal and the flip signal are 1, output the digital signal as 1; when the preparation signal and the flip signal are different, maintain the output digital signal from the previous moment.

[0109] In step S560, if the detected voltage is negative, input the preparation signal and the flip signal into the fifth comparator. When both the preparation signal and the flip signal are 0, the output digital signal is 0; when the preparation signal and the flip signal are different, maintain the output digital signal from the previous moment.

[0110] To prevent fluctuations in the output of the sensor located at the boundary between the fluidization zone 102 and the water zone 103, a preparation signal 507 and a flip signal 508 are introduced. The preparation signal 507 is a digital signal obtained by comparing the detected voltage 403 with a zero voltage 506. A first flip voltage 504 and a second flip voltage 505, namely E+ and E-, are introduced. The flip signal 508 is a digital signal obtained by comparing the detected voltage 403 with either the first flip voltage 504 or the second flip voltage 505 under different conditions. The final output digital signal 511 is obtained by comparing the preparation signal 507 with the flip signal 508. This output digital signal 511 guides the water flow rate of the water pump, thereby automatically controlling the expansion height.

[0111] Specifically, the detection voltage 403 is compared with the zero voltage 506 in the first comparator 501. If the detection voltage 403 is greater than zero, the preparation signal 507 is 1. At this time, the detection voltage 403 is compared with the first flip voltage 504 in the second comparator 502. If the detection voltage 403 is greater than the first flip voltage 504, the flip signal 508 is 1. If the detection voltage 403 is less than the first flip voltage 504, the flip signal 508 is 0. The preparation signal 507 and the flip signal 508 are entered into the fourth comparator 509 for comparison. If both are 1, the output digital signal 511 is 1. If they are different, it means that an invalid jump has occurred, and the output digital signal 511 of the previous moment is maintained.

[0112] Simultaneously, the detected voltage 403 is compared with the zero voltage 506 in the first comparator 501. If the detected voltage 403 is less than zero, the preparation signal 507 is 0. At this time, the detected voltage 403 is compared with the second flip voltage 505 in the third comparator 503. If the detected voltage 403 is greater than the second flip voltage 505, the flip signal 508 is 1. If the detected voltage 403 is less than the second flip voltage 505, the flip signal 508 is 0. The preparation signal 507 and the flip signal 508 are entered into the fifth comparator 510 for comparison. If both are 0, the output digital signal 511 is 0. If they are different, it means that an invalid jump has occurred, and the output digital signal 511 of the previous moment is maintained.

[0113] In some examples, Figure 8 The analog signal of the detected voltage shown is... Figure 9 The output digital signals shown correspond to each other and represent the detection results for a specific time period.

[0114] In the description of this specification, the use of terms such as "an embodiment," "some examples," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples" indicates that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0115] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.

Claims

1. A Fenton fluidized bed, characterized in that, include: The fluidized bed body has an inlet at the bottom and an outlet at the top. A particle bed is provided inside the fluidized bed body. The particle bed defines a fluidization zone and a water zone at the top of the fluidization zone inside the fluidized bed body. Water can enter the fluidized bed body through the inlet, pass through the particle bed, and flow out of the fluidized bed body through the outlet. A sensor assembly is disposed on the inner wall of the fluidized bed body. The sensor assembly includes at least three sensors: a first sensor located in the fluidization zone, a second sensor located at the designed expansion height, and a third sensor located in the water zone. The sensor assembly is used to measure the expansion height of the particle bed. The first, second, and third sensors all include a deformable plate disposed on the inner wall of the fluidized bed body. The deformable plate is inclined and extends towards the bottom of the fluidized bed body. The fluid flow direction in the fluidization zone is different from that in the water zone. In the fluidization zone, the water flow and the particle structure in the particle bed have an upward flow direction in the central region, forming a vortex around the central region, and a downward flow direction in the region near the inner wall of the fluidized bed body. In the water zone, the water flow has an upward flow direction. The deformable plate can deform in different directions in the fluidization zone and the water zone. Strain structures are provided on opposite sides of the deformable plate. When the deformable plate deforms, the strain structures are subjected to tensile or compressive forces, which increases or decreases the resistance of the strain structures.

2. The Fenton fluidized bed according to claim 1, characterized in that, The first sensor, the second sensor, and the third sensor all include a protective housing. The protective housing is disposed on the inner wall of the fluidized bed body, and the protective housing and the inner wall of the fluidized bed body form an isolation space. The portion of the deformable plate connected to the inner wall of the fluidized bed body is located within the isolation space.

3. The Fenton fluidized bed according to claim 2, characterized in that, The deformable plate extends from the inner wall of the fluidized bed body to form the isolation space. A flexible sealing structure is provided at the position where the deformable plate contacts the protective shell to enable a flexible connection between the deformable plate and the protective shell.

4. A method for measuring and controlling the bed expansion height inside a Fenton fluidized bed, applied to the Fenton fluidized bed as described in any one of claims 1 to 3, characterized in that: Water is introduced into the fluidized bed body through the inlet and discharged from the outlet. In the fluidized zone, the water flow and the particle structure in the particle bed flow upward in the central region, forming vortices around the central region, and downward in the region near the inner wall of the fluidized bed body; in the water zone, the water flow is upward. When the sensor detects that the surrounding fluid is flowing downwards, the sensor is currently in the fluidized zone or the particle bed expansion height has reached the sensor height; when the sensor detects that the surrounding fluid is flowing upwards, the sensor is currently in the water zone or the particle bed expansion height has not reached the sensor height. Connect the sensor to a detection circuit that includes a resistor to obtain the detection voltage E0; The detected voltage is input to the analog-to-digital converter (ADC). The ADC obtains a ready signal and a flip signal by comparing the voltages. Based on the dual judgment of the ready signal and the flip signal, the output digital signal is obtained. The analog-to-digital converter determines the expansion height by outputting a digital signal, and then quantitatively adjusts the water flow rate based on the deviation between the expansion height and the design height.

5. The method for measuring and controlling the bed expansion height inside the Fenton fluidized bed according to claim 4, characterized in that, When the sensor detects that the surrounding fluid is flowing downwards, the current sensor is in the fluidized zone or the particle bed expansion height reaches the sensor height; when the sensor detects that the surrounding fluid is flowing upwards, the current sensor is in the water zone or the particle bed expansion height has not reached the sensor height, including: A deformation plate with strain structures on both the top and bottom sides is set as part of the sensor. When the fluid around the sensor flows downwards, the deformable plate bends downwards. The strain structure at the top of the deformable plate is under tension, and its resistance increases; the strain structure at the bottom of the deformable plate is under compression, and its resistance decreases. When the fluid around the sensor flows upward, the deformation plate bends upward. The strain structure at the top of the deformation plate is compressed, and its resistance decreases. The strain structure at the bottom of the deformation plate is stretched, and its resistance increases.

6. The method for measuring and controlling the bed expansion height inside the Fenton fluidized bed according to claim 4, characterized in that, The step of connecting the sensor to a detection circuit including a resistor to obtain a detection voltage includes: The detection circuit includes both adjustable and fixed resistors. Before testing, adjust the adjustable resistor according to the initial deformation of the sensor to bring the output voltage to zero.

7. The method for measuring and controlling the bed expansion height inside the Fenton fluidized bed according to claim 4, characterized in that, The step of inputting the detected voltage into the analog-to-digital converter (ADC), and the ADC obtaining a preparation signal and a toggle signal by comparing the voltages, includes: The initial stage digital signals of the analog-to-digital converter, which includes the first comparator, the second comparator, and the third comparator, are all set to 1. A first switching voltage E+ is set on the second comparator, and a second switching voltage E- is set on the third comparator. The detection voltage is input to the first comparator. When the detection voltage is positive, the preparation signal is set to 1. The detection voltage is input to the second comparator. When the detection voltage is greater than the first flip voltage, the flip signal is set to 1. When the detection voltage is less than the first flip voltage, the flip signal is set to 0. When the detected voltage is negative, the preparation signal is set to 0. The detected voltage is input to the third comparator. When the detected voltage is less than the second flip voltage, the flip signal is set to 0. When the detected voltage is greater than the second flip voltage, the flip signal is set to 1.

8. The method for measuring and controlling the bed expansion height inside the Fenton fluidized bed according to claim 7, characterized in that, Also includes: Configure a fourth and a fifth comparator in the analog-to-digital converter; When the detected voltage is positive, the preparation signal and the flip signal are input to the fourth comparator. When both the preparation signal and the flip signal are 1, the output digital signal is 1. When the ready signal is different from the toggle signal, maintain the output digital signal from the previous moment; When the detected voltage is negative, the preparation signal and the flip signal are input to the fifth comparator. When both the preparation signal and the flip signal are 0, the output digital signal is 0; when the preparation signal and the flip signal are different, the output digital signal of the previous moment is maintained.

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