PAM flocculant intelligent dissolving device and control method thereof

Abstract

This invention relates to the field of automated preparation technology of water treatment agents, and discloses an intelligent dissolution device for PAM flocculant and its control method. The device includes a pre-dissolution chamber, a main dissolution chamber, a maturation chamber, and a control unit. The pre-dissolution chamber has a swirling negative pressure powder suction device at the top and a microporous aeration pipe and an ultra-microbubble generator at the bottom. An online concentration sensor is mounted on the chamber wall. The main dissolution chamber has a low-shear variable frequency stirring paddle, an online viscometer and a temperature sensor mounted on the chamber wall, and ultrasonic probes evenly distributed at the bottom. The maturation chamber has a low-speed push-flow stirring paddle, and the outlet pipe has a conductivity sensor and an electric discharge valve. The downstream of the electric discharge valve is connected back to the pre-dissolution chamber via a return pipe. The control unit adjusts the screw feeder speed and water inlet opening based on the concentration detection value, adjusts the stirring speed and ultrasonic power based on the viscosity after temperature compensation, and controls the discharge valve and the return solenoid valve based on the conductivity detection value. This device can improve the uniformity of PAM dissolution and viscosity retention rate, and achieve automatic re-dissolution of substandard solutions.

Description

Technical Field

[0001] This invention relates to the field of automated preparation technology of water treatment agents, and in particular to an intelligent dissolution device for PAM flocculant and its control method. Background Technology

[0002] Polyacrylamide (PAM), as a high-molecular-weight organic flocculant, is widely used in water treatment processes such as coal slurry water clarification, municipal sludge dewatering, and pretreatment of dyeing and printing wastewater. The concentration uniformity, apparent viscosity retention rate, and aging homogeneity of the PAM solution directly determine the downstream flocculation and sedimentation rate and the moisture content of the dewatered filter cake. Therefore, efficient dissolution and stable output of PAM dry powder are key aspects of the automated preparation of water treatment agents.

[0003] However, existing PAM dry powder dissolution devices have significant shortcomings in the three aspects of dry powder dispersion, shear control, and dissolution process sensing. These shortcomings can be summarized into the following three typical technical routes and their defects.

[0004] The first type is a single-chamber, fixed-speed mechanical stirring dissolution device. For example, Chinese utility model patent CN208194131U, published on December 7, 2018, entitled "Dissolving and Stirring Device for Wastewater Treatment Agents," discloses a dissolution device based on a single stirring tank combined with a drive motor and a reducer. The drive motor drives the reducer, which in turn drives the stirring shaft. Stirring blades are installed on the stirring shaft. Dry powder is fed into the water surface through an open feed hopper and then mechanically dispersed by the blades. The drawbacks of this solution are: the dry powder addition point is concentrated, and "fish-eye" gel clumps easily form on the water surface, with an aggregation rate as high as 8% to 15%; the linear velocity at the blade tip usually exceeds 5 m / s, and the PAM polymer chains are subjected to continuous mechanical shear degradation, resulting in a loss rate of 15% to 30% in intrinsic viscosity; at the same time, there is no feedback control throughout the dissolution process, and the concentration deviation usually exceeds ±0.03% w / v, making it difficult to guarantee the accuracy of downstream dosing.

[0005] The second type is a timed, staged stirring dissolution device. For example, Chinese utility model patent CN203090778U, published on July 31, 2013, entitled "An Integrated Automatic Dosing Device for PAM", discloses an integrated automatic dosing device for PAM, including a dosing mixer, a dry powder dispenser, a stirring paddle, a dry powder dosing device, a reagent dissolution tank, and an electrical control cabinet. This device controls the switching between dry powder dosing and stirring according to a set time sequence through the electrical control cabinet to ensure the PAM maturation time. Its drawbacks are as follows: the stage switching is based on time rather than solution state, making it difficult to adapt to different molecular weight PAMs (such as 8 million and 25 million) and different water temperatures (5℃~35℃), resulting in both under-dissolution and over-cooking; at the same time, it lacks coupling compensation between viscosity and temperature, and seasonal water temperature fluctuations cause the effective viscosity of the solution to deviate by more than ±10%; in addition, the ripening endpoint relies on manual sampling and visual judgment, with a feedback lag of 10min~30min, and poor response capability when the working conditions change suddenly (such as material interruption, sudden increase in the conductivity of raw water).

[0006] The third type is the single-parameter closed-loop feedback dissolution device. For example, Chinese utility model patent CN212770034U, published on March 23, 2021, entitled "A PAM Dosing Output Device," discloses a PAM dosing output device applied to coal slurry water treatment. The dissolution tank is equipped with a concentration meter and a level gauge, while the wastewater tank is equipped with a turbidity meter and an electromagnetic flow meter. The device adjusts the dosage through feedback from the concentration meter. The drawbacks of this solution are: relying solely on concentration feedback cannot identify whether the PAM molecular chains are fully expanded, often resulting in a false dissolution phenomenon of "concentration meeting the standard but viscosity insufficient," and the flocculation qualification rate is less than 85%; the device is not equipped with online viscosity detection, and cannot switch the stirring mode based on the real-time state of the solution, which easily leads to local over-concentration and agglomeration; furthermore, the single-loop controller is prone to overshoot and oscillation under high molecular weight PAM conditions due to the large hysteresis characteristics of the controlled object, and the control response time is usually greater than 60 seconds.

[0007] In summary, existing PAM dry powder dissolution devices generally suffer from common problems such as uneven dry powder dispersion, molecular chain degradation caused by mechanical shearing, lack of solution state criteria for stage switching, inability to identify false dissolution phenomena due to single parameter feedback, and lack of temperature and ionic strength coupling compensation. These issues make it difficult to meet the engineering requirements for stable output of PAM solution quality under various operating conditions. Summary of the Invention

[0008] The purpose of this invention is to provide a smart PAM flocculant dissolution device and its control method. It employs a three-stage cavity structure consisting of a pre-dissolution cavity, a main dissolution cavity, and a maturation cavity arranged sequentially along the material flow direction. In the pre-dissolution cavity, swirling negative pressure powder absorption and microbubble synergistic dispersion are implemented. In the main dissolution cavity, low-shear stirring and ultrasonic synergistic dispersion based on the viscosity change rate slope are implemented. In the maturation cavity, liquid quality discrimination based on conductivity interlocking is implemented. The control unit executes an adaptive PID algorithm containing a temperature compensation sub-model and a historical data learning module to achieve decoupling and synergistic effects between concentration and viscosity closed-loop systems. This results in a PAM solution with advantages such as low "fish-eye" gel cluster formation rate, high intrinsic viscosity retention rate, excellent concentration uniformity, and strong adaptability to various operating conditions. It plays an important role in water treatment processes such as coal slurry water clarification, municipal sludge dewatering, water supply pretreatment, and industrial wastewater flocculation.

[0009] To achieve the above objectives, the following technical solution is adopted: In a first aspect, the present invention provides a PAM flocculant intelligent dissolution device, comprising a pre-dissolution chamber, a main dissolution chamber and a maturation chamber arranged sequentially along the material flow direction, and a control unit; The top of the pre-dissolving chamber is equipped with a swirling negative pressure powder suction device, which is connected to the discharge port of the screw feeder at the bottom of the dry powder silo; a water inlet flow meter and an electric water inlet regulating valve are installed sequentially along the water flow direction on the water inlet pipe at the bottom of the pre-dissolving chamber, an online concentration sensor is installed on the chamber wall, and a microporous aeration pipe is arranged circumferentially at the bottom of the chamber, with the air inlet end of the microporous aeration pipe connected to an ultra-micro bubble generator; The main dissolution chamber is equipped with a low-shear variable frequency stirring paddle, an online viscometer and a temperature sensor are installed on the chamber wall, and ultrasonic probes are evenly distributed in a ring array along the bottom of the chamber. The curing chamber is equipped with a low-speed stirring paddle, and a conductivity sensor and an electric liquid outlet valve are sequentially installed along the flow direction on the outlet pipe. The downstream of the electric liquid outlet valve is connected to the inlet of the pre-dissolving chamber through a return pipe, and a solenoid valve is installed on the return pipe. The signal output terminals of the online concentration sensor, online viscometer, temperature sensor, and conductivity sensor are respectively connected to the corresponding signal input terminals of the control unit; the control output terminals of the control unit are respectively connected to the corresponding control terminals of the screw feeder, the electric water inlet regulating valve, the low-shear variable frequency stirring paddle, the ultrasonic probe, the electric liquid outlet valve, and the solenoid valve on the return pipeline. The control unit is configured to: The real-time concentration detection value of the online concentration sensor is obtained, and the rotation speed of the screw feeder and the opening degree of the electric regulating valve for water inlet are adjusted according to the target concentration and the real-time concentration detection value. The real-time viscosity detection value of the online viscometer and the real-time temperature detection value of the temperature sensor are obtained. The real-time viscosity is compensated for by temperature to obtain the equivalent viscosity. Based on the target equivalent viscosity and the real-time equivalent viscosity detection value, the rotation speed of the low-shear variable frequency stirring paddle and the power of the ultrasonic probe are adjusted. The real-time conductivity detection value of the conductivity sensor is obtained, the quality of the discharged liquid is determined based on the conductivity detection value, and the opening and closing of the electric discharge valve and the solenoid valve on the return pipeline are driven.

[0010] Preferably, in the above-mentioned PAM flocculant intelligent dissolving device, the pre-dissolving chamber and the main dissolving chamber are connected by a connecting pipe with a guide plate, and the main dissolving chamber and the maturation chamber are connected by an overflow weir with adjustable weir crest height; the pre-dissolving chamber is equipped with a low-speed anchor-type pre-dispersion stirring paddle, and a liquid level sensor is also installed on the chamber wall, and the signal output terminal of the liquid level sensor is connected to the signal input terminal of the control unit.

[0011] Preferably, in the above-mentioned PAM flocculant intelligent dissolving device, the swirling negative pressure powder suction device includes a Venturi nozzle and an induced draft fan that cooperates with the Venturi nozzle. The ratio of the throat diameter of the Venturi nozzle to the discharge port diameter of the screw feeder is 1:1.5 to 1:2.5. The axis of the dry powder inlet of the Venturi nozzle forms an angle of 30° to 60° with the airflow direction. The swirling chamber of the swirling negative pressure powder suction device is provided with an anti-bridging conical disturbance component. The control end of the induced draft fan is connected to the control output end of the control unit. The control unit is configured to correspondingly control the air volume of the induced draft fan and the rotation speed of the screw feeder, so that the air-powder mass ratio is maintained at 20:1 to 50:1.

[0012] Preferably, in the above-mentioned intelligent dissolving device for PAM flocculants, the micropore diameter of the microporous aeration tube is 50μm~150μm, the particle size of the bubbles generated by the ultra-microbubble generator is 50μm~200μm, and the aeration rate is 0.3m³ / h. 3 / h~1.5m 3 / h; the rotational speed range of the low-speed anchor-type pre-dispersion mixing paddle is 10r / min to 30r / min, and the linear velocity at the blade tip does not exceed 1m / s.

[0013] Preferably, in the above-mentioned PAM flocculant intelligent dissolving device, the high-speed dispersion mode speed range of the low-shear variable frequency stirring paddle is 150 r / min to 300 r / min, and the low-speed maturation mode speed range is 40 r / min to 80 r / min.

[0014] Preferably, in the above-mentioned intelligent dissolving device for PAM flocculants, the ultrasonic probe operates at a frequency of 20kHz to 80kHz and has a power density of 0.5W / cm³. 2 ~3.0W / cm2 The array consists of 3 to 8 probes, and the distance between adjacent probes is 1 to 2 times the wavelength of the corresponding frequency ultrasound.

[0015] Preferably, in the above-mentioned intelligent dissolving device for PAM flocculants, the control unit incorporates a temperature compensation sub-model, a historical data learning module, a conductivity-concentration coupling correction module, and a protection logic module; wherein: The temperature compensation sub-model responds to the measured viscosity output by the online viscometer. and the real-time temperature output by the temperature sensor According to the formula The equivalent viscosity was calculated. ,in To correct the parameters, The preset calibration reference temperature; The historical data learning module responds to the input, time-continuous running data and calculates the updated base proportional gain using a rolling average algorithm. Basic Integral Time Switching threshold with viscosity slope The parameter difference before and after the update is limited to within the set parameter difference threshold range, and the updated parameters are written back to the PID parameter register. The conductivity-concentration coupling correction module, in response to the real-time conductivity output by the conductivity sensor and the real-time concentration output by the online concentration sensor, performs ion strength coupling calculations to obtain the corrected equivalent concentration. ; in response to the real-time conductivity deviating from the reference conductivity by more than a first set range or the equivalent concentration If the concentration deviates from the target concentration by more than the second set range, a reflux reconstitution command is output to the execution output terminal of the control unit. The execution output terminal controls the electric dispensing valve to close and controls the solenoid valve on the reflux pipeline to open. The protection logic module responds to the status signals of the liquid level sensor, screw feeder, microbubble generator and online viscometer. When the liquid level in the pre-dissolving chamber is detected to be lower than the set lower limit or the current of the screw feeder is lower than the no-load value for three consecutive sampling cycles, it outputs a material cut-off protection command to the execution output terminal of the control unit. The execution output terminal controls the screw feeder to stop running and triggers an audible and visual alarm. When the gas source pressure of the microbubble generator is detected to be lower than the set gas source pressure value, a gas cut-off protection command is output to the execution output terminal of the control unit, and the execution output terminal controls the microbubble generator to stop running and triggers an audible and visual alarm. When the output value of the online viscometer is detected to change abruptly beyond the set threshold within a set time, a sensor abnormality protection command is output to the execution output terminal of the control unit, which triggers an audible and visual alarm.

[0016] Secondly, the present invention provides a method for intelligent dissolution control of PAM flocculants using the device described above, the control method comprising: Control the electric regulating valve to inject water into the pre-dissolution chamber to the set level, and control the microbubble generator to start pre-aeration; After pre-aeration is completed, the blower and screw feeder are started to introduce PAM dry powder into the pre-dissolution chamber through the swirling negative pressure powder suction device in a pneumatic dispersion manner. Based on the set target concentration and the PAM mass concentration in the pre-dissolution chamber detected in real time by the online concentration sensor, the speed of the screw feeder and the opening of the water inlet electric regulating valve are adjusted to maintain the air-powder mass ratio at 20:1~50:1 and the water-powder mass ratio at 300:1~800:1. After the material in the pre-dissolving chamber flows into the main dissolving chamber through the guide plate, the equivalent viscosity is calculated based on the solution viscosity detected in real time by the online viscometer and the solution temperature detected in real time by the temperature sensor, using a built-in temperature compensation sub-model. ; Based on the equivalent viscosity Calculate the slope of the viscosity change rate. ,when Viscosity slope switching threshold greater than preset And when the duration is not less than the set first duration, the low-shear variable frequency agitator is switched to high-speed dispersion mode and the ultrasonic probe is turned on. The high-speed dispersion mode is when the low-shear variable frequency agitator operates at a speed of 150 r / min to 300 r / min; when Less than When the duration is not less than the set second duration, the low-shear variable frequency stirring paddle is switched to low-speed maturation mode and the ultrasonic probe is turned off. n is a set positive number less than 1. The low-speed maturation mode is when the low-shear variable frequency stirring paddle runs at a speed of 40r / min to 80r / min. After the material in the main dissolving chamber flows into the maturation chamber through the overflow weir for maturation, the equivalent concentration corrected for ionic strength is calculated based on the real-time detection of the outlet conductivity by the conductivity sensor and the detection value by the online concentration sensor. When the equivalent concentration When the product is within the preset acceptable range, the electric discharge valve (32) is opened to output the finished product; when the equivalent concentration... When the material exceeds the preset qualified range, the electric discharge valve (32) is closed and the solenoid valve on the return pipeline is opened, so that the material returns to the pre-dissolution chamber for re-dissolution.

[0017] Preferably, in the above-mentioned intelligent dissolution control method for PAM flocculants, during the process of adjusting the speed of the screw feeder and the opening of the electric regulating valve for the inlet water, the concentration deviation |ΔC| between the target concentration and the real-time concentration detection value is calculated; when |ΔC| is less than or equal to the preset concentration deviation value, the adjustment is performed according to the preset basic PID parameters; when |ΔC| is greater than the preset concentration deviation value, the proportional gain is adjusted to m times the basic proportional gain for accelerated adjustment, where m is a positive number greater than 1; the basic proportional gain is updated according to a preset cycle. Basic Integral Time Switching threshold with viscosity slope .

[0018] Preferably, in the above-mentioned intelligent dissolution control method for PAM flocculants, the control method further includes: During the entire dissolution process, if the liquid level in the pre-dissolution chamber is lower than the preset lower limit or the current of the screw feeder is lower than the no-load value for three consecutive sampling cycles, the material cut-off protection is triggered. When the gas source pressure of the microbubble generator is lower than the set gas source pressure value, the gas supply interruption protection is triggered. When the output value of the online viscometer changes abruptly beyond a set threshold within a set time, the sensor is deemed abnormal, and an audible and visual alarm is triggered. When the temperature of the prepared water is found to be lower than the set temperature value, the heating device in the pre-dissolving chamber is controlled to operate, so that the temperature of the prepared water is maintained within the preset temperature threshold range.

[0019] The beneficial effects of this invention are: (1) In this invention, the swirling negative pressure powder suction device at the top of the pre-dissolving chamber and the ultra-microbubble generator at the bottom of the chamber work together to uniformly introduce PAM dry powder into the liquid surface and complete the primary wetting under the dual action of pneumatic dispersion and the shearing carried by rising microbubbles. Compared with the traditional open feeding method combined with single mechanical stirring, this invention can effectively suppress the formation of fish-eye gel clusters and significantly shorten the primary swelling time.

[0020] (2) The present invention uses a near-infrared transmission online concentration sensor in the pre-dissolution chamber, a screw feeder, and an electric regulating valve for water inlet to form a concentration feedback control, combined with an adaptive PID large deviation fast adjustment mode, so that the deviation between the actual mass concentration of PAM solution and the target concentration is precisely controlled within an extremely narrow range. Compared with the manual intermittent batching method, the concentration uniformity is greatly improved.

[0021] (3) This invention utilizes a rotary online viscometer in the main dissolution chamber for real-time feedback drive. The low-shear variable-frequency stirring paddle automatically switches between high-speed dispersion and low-speed maturation modes based on the viscosity change rate slope, and is supplemented by the low-shear cavitation energy of the ultrasonic probe to replace part of the mechanical shear. Compared with a fixed-speed stirring scheme, the intrinsic viscosity retention rate of the PAM solution is significantly improved, effectively avoiding the loss of flocculation performance caused by polymer chain breakage.

[0022] (4) The present invention enhances the wetting and dispersion of PAM particles through the synergistic effect of ultrasonic probe array and frequency conversion stirring. Compared with the single mechanical stirring dissolution process, the dissolution time of the whole machine is significantly shortened, and the dissolution and maturation cycle of a single batch is compressed.

[0023] (5) This invention enables the device to operate stably under a wide water temperature range, a wide molecular weight range, and a full spectrum of anionic, cationic, and nonionic PAM conditions through a viscosity-temperature coupling compensation model triggered by a temperature sensor and PID parameters updated by a historical data learning module. Compared with open-loop control schemes without temperature compensation, the flocculation qualification rate remains at a very high level throughout the year.

[0024] (6) This invention utilizes a quality interlocking loop formed by a conductivity sensor at the outlet of the curing chamber, an electric dispensing valve, and a reflux pipeline to automatically reflux and redissolve substandard solutions. Compared to manual timed dispensing, the effective utilization rate of PAM raw materials per unit mass is improved, and the average annual drug consumption cost is significantly reduced. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a structural diagram of a PAM flocculant intelligent dissolving device provided in an embodiment of the present invention; Figure 2 The diagram shows a partial enlargement of the key components of the swirling negative pressure powder suction device and the main dissolving chamber, as well as the PAM dissolving process flow, provided in the embodiments of the present invention; wherein, (a) is a structural diagram of the swirling negative pressure powder suction device; (b) is a partial enlarged structural diagram of the key components of the main dissolving chamber; and (c) is a flowchart of the PAM dissolving process. Figure 3 A control logic block diagram of the control unit provided in an embodiment of the present invention; Figure 4 Viscosity-temperature compensation curves of the temperature compensation sub-model provided in this embodiment of the invention under different PAM types and concentrations; Figure 5 A flowchart of a smart dissolution method for PAM flocculant provided in an embodiment of the present invention; Figure 6 A flowchart illustrating the protection and operating condition adaptation process provided in this embodiment of the invention; Figure 7 Another flowchart of a PAM flocculant intelligent dissolution method provided in an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached figures: 1. Pre-dissolving chamber; 2. Main dissolving chamber; 3. Maturation chamber; 4. Control unit; 5. Guide plate; 6. Overflow weir; 11. Screw feeder; 12. Low-speed anchor-type pre-dispersion agitator; 13. Near-infrared transmission online concentration sensor; 14. Inlet water flow meter; 15. Electric inlet water regulating valve; 16. Swirl negative pressure powder suction device; 161. Exhaust fan; 17. Microporous aeration pipe; 171. Microbubble generator; 18. Liquid level sensor; 21. Low-shear variable frequency agitator; 22. Rotary online viscometer; 23. Temperature sensor; 24. Ultrasonic probe; 31. Conductivity sensor; 32. Electric outlet valve; 33. Low-speed propulsion agitator; 34. Return pipeline. Detailed Implementation

[0028] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0029] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0030] Example 1: This invention provides an intelligent dissolving device for PAM flocculants, such as... Figure 1 and Figure 2As shown, the intelligent dissolving device for PAM flocculant includes a pre-dissolving chamber 1, a main dissolving chamber 2, and a maturation chamber 3 arranged sequentially along the material flow direction, as well as a control unit 4. The top of the pre-dissolving chamber 1 is equipped with a swirling negative pressure powder suction device 16, which is connected to the discharge port of the screw feeder 11 at the bottom of the dry powder silo. A water inlet flow meter 14 and an electric water inlet regulating valve 15 are sequentially installed on the water inlet pipe at the bottom of the pre-dissolving chamber 1 along the water flow direction. An online concentration sensor 13 is installed on the chamber wall. Microporous aeration pipes 17 are arranged circumferentially at the bottom of the chamber, and the air inlet end of the microporous aeration pipes 17 is connected to an ultra-microbubble generator 171. The main dissolving chamber 2 is equipped with a low-shear variable frequency stirring paddle 21. An online viscometer 22 and a temperature sensor 23 are installed on the chamber wall. The bottom of the chamber... Ultrasonic probes 24 are evenly distributed along the ring array; a low-speed propulsion stirring paddle 33 is provided in the curing chamber 3, and a conductivity sensor 31 and an electric liquid outlet valve 32 are sequentially provided along the flow direction on the outlet pipe. Downstream of the electric liquid outlet valve 32, it is connected to the inlet of the pre-dissolving chamber 1 through the return pipe 34, and a solenoid valve is provided on the return pipe 34; the signal output terminals of the online concentration sensor 13, online viscometer 22, temperature sensor 23, and conductivity sensor 31 are respectively connected to the corresponding signal input terminals of the control unit 4; the control output terminals of the control unit 4 are respectively connected to the corresponding control terminals of the screw feeder 11, the electric water inlet regulating valve 15, the low-shear variable frequency stirring paddle 21, the ultrasonic probes 24, the electric liquid outlet valve 32, and the solenoid valve on the return pipe 34.

[0031] In practice, the pre-dissolving chamber 1, the main dissolving chamber 2, and the maturation chamber 3 are arranged sequentially along the material flow direction to form a three-stage continuous dissolving process. This provides independent processing spaces for the step-by-step dissolution and maturation of PAM dry powder, avoiding interference between the process requirements of different dissolution stages.

[0032] The cyclone negative pressure powder suction device 16 is connected to the discharge port of the screw feeder 11 at the bottom of the dry powder silo, introducing the PAM dry powder metered out by the screw feeder 11 into the pre-dissolving chamber 1 by pneumatic dispersion, so that the dry powder particles are fully dispersed by the airflow before contacting the liquid surface. The screw feeder 11 realizes the quantitative delivery of PAM dry powder, providing a stable powder supply for the dissolution process. The inlet water flow meter 14 detects the inlet water flow rate into the pre-dissolving chamber 1 in real time, and the inlet water electric regulating valve 15 regulates the inlet water flow rate. The two work together to achieve precise control of the water-powder mass ratio. The online concentration sensor 13 detects the mass concentration of the PAM solution in the pre-dissolving chamber 1 in real time, providing feedback for the adjustment of powder and inlet water flow rates. The microporous aeration pipe 17 is arranged circumferentially along the bottom of the pre-dissolving chamber 1, and is driven by the ultra-microbubble generator 171 to generate microbubbles. The rising microbubble group forms a gentle interfacial shearing and carrying effect on the PAM particles at the liquid surface, promoting rapid wetting and dispersion of the particles.

[0033] A low-shear variable-frequency stirring paddle 21 stirs the solution in the main dissolution chamber 2, accelerating the dissolution of PAM particles and the unfolding of molecular chains. The rotation speed is adjusted by frequency conversion to meet the shear requirements of different dissolution stages. An online viscometer 22 detects the apparent viscosity of the solution in real time, reflecting the degree of PAM molecular chain unfolding. A temperature sensor 23 detects the solution temperature in real time, providing temperature parameters for correcting the viscosity readings. Ultrasonic probes 24 are evenly distributed in a ring array along the bottom of the main dissolution chamber 2, generating ultrasonic cavitation energy to assist and enhance the dispersion and dissolution of PAM particles, reducing the damage to the polymer chains caused by mechanical shear.

[0034] A low-speed agitator 33 propels the solution in the maturation chamber 3 to flow slowly, creating a uniform flow pattern and ensuring thorough homogenization and maturation. A conductivity sensor 31 monitors the conductivity of the solution at the outlet of the maturation chamber 3 in real time, aiding in the assessment of the solution's quality. An electrically operated outlet valve 32 controls the flow of the finished product solution. A reflux line 34 connects the downstream of the electrically operated outlet valve 32 to the inlet of the pre-dissolving chamber 1, enabling the refluxing and redissolving of substandard solutions; a solenoid valve on the reflux line 34 controls its on / off state.

[0035] The signal output terminals of the online concentration sensor 13, online viscometer 22, temperature sensor 23, and conductivity sensor 31 are respectively connected to the corresponding signal input terminals of the control unit 4, transmitting each detection parameter to the control unit 4 in real time. The control output terminals of the control unit 4 are respectively connected to the corresponding control terminals of the screw feeder 11, the electric inlet regulating valve 15, the low-shear variable frequency agitator 21, the ultrasonic probe 24, the electric outlet valve 32, and the solenoid valve on the return pipeline 34. Based on the received detection parameters, the control unit 4 outputs corresponding control commands to adjust the operating status of each actuator.

[0036] In an exemplary working process, such as Figure 2As shown in (c), the electric regulating valve 15 is activated to inject water into the pre-dissolving chamber 1 to the set level. The microbubble generator 171 is activated, driving the microporous aeration pipe 17 to generate microbubbles for pre-aeration. The screw feeder 11 and the cyclone negative pressure powder suction device 16 are activated, and the PAM dry powder falls into the liquid surface of the pre-dissolving chamber 1 through the cyclone negative pressure powder suction device 16 in a pneumatic dispersion manner. The online concentration sensor 13 detects the PAM concentration in the pre-dissolving chamber 1 in real time and transmits it to the control unit 4. The control unit 4 adjusts the speed of the screw feeder 11 and the opening degree of the electric regulating valve 15 according to the difference between the target concentration and the real-time concentration. The pre-dissolved material flows into the main dissolving chamber 2. The online viscometer 22 and the temperature sensor 23 detect the viscosity and temperature of the solution respectively and transmit them to the control unit 4. The control unit 4 adjusts the speed of the low-shear variable frequency stirring paddle 21 and the opening and closing of the ultrasonic probe 24 according to the corrected equivalent viscosity. The dissolved material flows into the maturation chamber 3 for maturation. The conductivity sensor 31 detects the conductivity of the liquid and transmits it to the control unit 4. When the liquid quality is qualified, the control unit 4 controls the electric liquid outlet valve 32 to open and output the finished liquid. When the liquid quality is unqualified, the control unit 4 controls the electric liquid outlet valve 32 to close and opens the solenoid valve on the return pipeline 34, so that the material returns to the pre-dissolution chamber 1 for redissolution.

[0037] This intelligent PAM flocculant dissolving device effectively inhibits the agglomeration of PAM dry powder into fish-eye gel clusters through the synergistic effect of the swirling negative pressure powder suction device 16 and the microporous aeration pipe 17, thus shortening the primary dispersion time. The control unit 4, based on dual-parameter feedback of online concentration and online viscosity, adjusts the powder inlet water flow rate and stirring ultrasonic parameters respectively, achieving dynamic and precise control of the dissolving process and improving the uniformity of solution concentration and viscosity retention. Through the effluent quality detection by the conductivity sensor 31 and the re-dissolving design of the reflux pipeline 34, the quality of the output finished liquid is ensured to be stable, improving the effective utilization rate of PAM raw materials.

[0038] As the core control component of the device, the control unit 4 receives real-time detection data from various sensors through the signal input terminal, processes it internally, and then sends control commands to the corresponding actuators through the control output terminal to achieve automated and precise control of the entire PAM flocculant dissolution process.

[0039] Specifically, the control unit 4 acquires the real-time concentration detection value from the online concentration sensor 13, compares the real-time concentration detection value with the preset target concentration, and adjusts the rotation speed of the screw feeder 11 and the opening degree of the electric water inlet regulating valve 15 according to the difference between the two, so that the concentration of PAM solution in the pre-dissolution chamber 1 is stabilized within the target value range. The control unit 4 acquires the real-time viscosity detection value from the online viscometer 22 and the real-time temperature detection value from the temperature sensor 23, calculates the equivalent viscosity from the real-time viscosity detection value through temperature compensation, compares the equivalent viscosity with the preset target equivalent viscosity, and adjusts the rotation speed of the low-shear variable frequency stirring paddle 21 and the power of the ultrasonic probe 24 according to the difference between the two, to adapt to the dispersion and maturation requirements of different dissolution stages. The control unit 4 acquires the real-time conductivity detection value of the conductivity sensor 31, and judges the quality of the solution exiting the ripening chamber 3 based on the real-time conductivity detection value. When the quality of the solution is qualified, the control unit 4 drives the electric outlet valve 32 to open and output the finished solution. When the quality of the solution is unqualified, the control unit 4 drives the electric outlet valve 32 to close and drives the solenoid valve on the return pipeline 34 to open, so that the unqualified solution returns to the pre-dissolution chamber 1 for resolution treatment.

[0040] In some embodiments, such as Figure 3 The diagram shown is a control logic block diagram of control unit 4. Control unit 4 includes a signal input layer, a PLC operation layer, and an execution output layer. Data is transmitted between these layers through a standardized signal interface. Solid arrows represent upward sensor feedback signals and downward execution control commands, while dashed arrows represent PID parameter self-learning and write-back loops.

[0041] The signal input layer is equipped with 5 independent analog input channels, namely AI-1 channel, AI-2 channel, AI-3 channel, AI-4 channel and AI-5 channel; AI-1 channel is connected to a rotary online viscometer 22, AI-2 channel is connected to an NIR concentration sensor 13, AI-3 channel is connected to a temperature sensor 23, AI-4 channel is connected to a conductivity sensor 31, and AI-5 channel is connected to a liquid level sensor 18; each input channel is equipped with a first-order low-pass filter unit to reduce noise in the raw signals collected by the sensors before transmitting them to the PLC computing layer.

[0042] The PLC computing layer is the core computing unit of the control unit, integrating eight functional modules: concentration deviation calculation module, viscosity slope calculation module, temperature compensation calculation module, conductivity-concentration coupling correction module, mode switching judgment logic module, historical data learning module, adaptive PID calculation module, and protection logic module. The concentration deviation calculation module receives the NIR concentration signal transmitted from the signal input layer, calculates the concentration deviation ΔC, and outputs it to the adaptive PID calculation module. The viscosity slope calculation module receives the viscosity signal transmitted from the signal input layer and calculates the viscosity change rate slope. k =Δ η / Δ t The output is then sent to the mode switching judgment logic module; the temperature compensation calculation module receives the temperature signal and viscosity signal transmitted from the signal input layer and calculates the equivalent viscosity. The signal is then output to the historical data learning module; the conductivity-concentration coupling correction module receives the conductivity signal and NIR concentration signal transmitted from the signal input layer, and calculates the equivalent concentration corrected for ion strength. The output is then sent to the protection logic module; the adaptive PID calculation module integrates a concentration loop and a viscosity loop dual control loop, outputting control commands to the execution output layer based on the concentration deviation ΔC, while simultaneously receiving PID parameters written back from the historical data learning module for self-tuning; the mode switching judgment logic module uses the calculated viscosity slope... k With preset threshold k The system compares the data with 0 and outputs a stirring mode switching command to the execution output layer; the historical data learning module uses a 24-hour rolling average algorithm to learn from the running data and update the basic PID parameters and viscosity slope switching threshold. k 0, and write the updated parameters back to the adaptive PID calculation module through the parameter write-back loop shown by the dashed line; the protection logic module outputs material cut-off, gas cut-off and sensor abnormality protection commands to the execution output layer according to the equivalent concentration Ceq and the status signals of each device.

[0043] The output layer is configured with 6 independent output channels: AO-1, ​​AO-2, AO-3, DO-1, DO-2, and DO-3. AO-1 connects to the screw feeder frequency converter, outputting a speed adjustment signal; AO-2 connects to the mixer motor frequency converter, outputting a mixing speed adjustment signal; AO-3 connects to the inlet electric regulating valve, outputting an opening adjustment signal; DO-1 connects to the ultrasonic probe power supply, outputting a power on / off control signal; DO-2 connects to the return solenoid valve, outputting an on / off control signal; and DO-3 connects to the alarm and HMI output unit, outputting audible and visual alarm signals and displaying data on the human-machine interface.

[0044] Based on the above control logic, in some embodiments, the control unit 4 incorporates a temperature compensation sub-model, a historical data learning module, a conductivity-concentration coupling correction module, and a protection logic module.

[0045] The temperature compensation sub-model responds to the measured viscosity output by the online viscometer 22. The real-time temperature T output by temperature sensor 23 is calculated according to the formula... The equivalent viscosity was calculated. ,in To correct the parameters, The preset calibration reference temperature is used. This temperature compensation sub-model can eliminate the influence of solution temperature fluctuations on viscosity detection values, so that the viscosity measured under different water temperature conditions can be uniformly converted to the equivalent viscosity at the calibration reference temperature. This provides a consistent and reliable criterion for viscosity control, avoids misjudgments caused by seasonal water temperature changes or inlet water temperature fluctuations, and ensures the accuracy of identifying the degree of PAM molecular chain expansion.

[0046] like Figure 4 The figure shows the viscosity-temperature compensation curves of the temperature compensation sub-model provided in this embodiment of the invention under different PAM types and concentrations. The horizontal axis in the figure represents the solution temperature. T The unit is °C, covering the commonly used operating temperature range of water treatment from 5 °C to 45 °C; the vertical axis represents the normalized equivalent viscosity value. η eq / η 0, where η 0 represents the standard viscosity value at a reference temperature of 25°C. The figure uses... T 0=25℃ is the unified reference point. At this point, the normalized value of the equivalent viscosity of all curves is 1.0, that is, the measured viscosity is equal to the standard viscosity at the reference temperature.

[0047] Figure 4 The curves include viscosity-temperature compensation curves for three types of PAM flocculants at three typical working concentrations. The solid line represents anionic PAM, the dashed line represents cationic PAM, and the dotted line represents nonionic PAM. A1, A2, and A3 correspond to the equivalent viscosity normalization curves of anionic PAM at concentrations of 0.10% w / v, 0.15% w / v, and 0.20% w / v, respectively. B1, B2, and B3 correspond to the equivalent viscosity normalization curves of cationic PAM at concentrations of 0.10% w / v, 0.15% w / v, and 0.20% w / v, respectively. C1, C2, and C3 correspond to the equivalent viscosity normalization curves of nonionic PAM at concentrations of 0.10% w / v, 0.15% w / v, and 0.20% w / v, respectively.

[0048] The curves show that the equivalent viscosity of the PAM solution decreases linearly with increasing temperature, and the magnitude of this decrease is positively correlated with the PAM type and solution concentration. At the same temperature, the higher the solution concentration, the greater the deviation of the normalized equivalent viscosity from 1.0. At the same concentration, the viscosity of nonionic PAM is most sensitive to temperature changes, followed by cationic PAM, while anionic PAM is relatively stable. The temperature compensation sub-model of this invention is based on the above linear variation law, with adjusted parameters... α The value range is -0.030℃. -1 ~-0.020℃ -1The calibration and adjustment can be performed within this range according to the actual type of PAM used and the target concentration. Through this temperature compensation sub-model, the measured viscosity at different temperatures can be uniformly corrected to the equivalent viscosity at a reference temperature of 25℃, eliminating the interference of seasonal water temperature fluctuations on viscosity detection results and ensuring that the viscosity control logic can accurately reflect the actual degree of PAM molecular chain expansion across the entire operating temperature range.

[0049] The historical data learning module responds to the input, continuously running data over time, and calculates the updated base proportional gain using a rolling average algorithm. Basic Integral Time Switching threshold with viscosity slope The system limits the parameter difference before and after the update to within a set parameter difference threshold range and writes the updated parameters back to the PID parameter register. This historical data learning module continuously accumulates the actual operating data of the device, automatically optimizes the PID control parameters and viscosity slope switching threshold, enabling control unit 4 to adapt to factors such as molecular weight differences of different batches of PAM raw materials, water quality changes, and equipment aging, maintaining control accuracy and response speed during long-term operation without the need for frequent manual parameter tuning.

[0050] The conductivity-concentration coupling correction module responds to the real-time conductivity output by the conductivity sensor 31 and the real-time concentration output by the online concentration sensor 13, and performs ion strength coupling calculations to obtain the corrected equivalent concentration. ; In response to the real-time conductivity deviating from the reference conductivity by more than a first set range or equivalent concentration If the concentration deviates from the target range by more than the second preset range, a refluxing and resolution command is output to the execution output terminal of the control unit 4. The execution output terminal controls the electric outlet valve 32 to close and the solenoid valve on the refluxing pipeline 34 to open. This conductivity-concentration coupling correction module can compensate for the interference of changes in ion strength in the raw water on concentration detection, avoid the distortion of concentration sensor readings caused by fluctuations in water conductivity, and accurately identify situations where the concentration meets the standard but the quality is unqualified due to insufficient dissolution or batch differences of raw materials. It automatically refluxing and resolvating the unqualified solution, thereby ensuring the stability of the output quality and the utilization rate of raw materials.

[0051] The protection logic module responds to the status signals of the liquid level sensor 18, screw feeder 11, microbubble generator 171, and online viscometer 22. When the liquid level in the pre-dissolving chamber 1 is detected to be lower than the set lower limit or the current of the screw feeder 11 is lower than the no-load value for three consecutive sampling cycles, a material cut-off protection command is output to the execution output terminal of the control unit 4. The execution output terminal controls the screw feeder 11 to stop running and triggers an audible and visual alarm. When the gas source pressure of the microbubble generator 171 is detected to be lower than the set gas source pressure value, a gas cut-off protection command is output to the execution output terminal of the control unit 4. The execution output terminal controls the microbubble generator 171 to stop running and triggers an audible and visual alarm. When the output value of the online viscometer 22 is detected to change abruptly within a set time and exceed the set change threshold, a sensor abnormality protection command is output to the execution output terminal of the control unit 4. The execution output terminal switches to the open-loop control mode estimated by the temperature-concentration model and triggers an audible and visual alarm. This protection logic module can promptly identify and execute corresponding protection actions when the device experiences material shortage, gas shortage, or sensor failure, preventing control failure or equipment damage caused by raw material interruption, gas source failure, or signal abnormality. At the same time, it automatically switches to open-loop estimation mode when the sensor is abnormal, ensuring that the device can still maintain basic operation under fault conditions and avoid production interruption.

[0052] It should be noted that the control unit 4 can be any existing control device such as an industrial programmable logic controller (PLC), an embedded microcontroller (MCU), or an industrial control computer (IPC). The temperature compensation sub-model, the conductivity-concentration coupling correction module, and the logic judgment parts in the protection logic module are stored as fixed algorithm programs in the read-only memory or flash memory of the control unit 4, and are executed by the central processing unit (CPU) or digital signal processor (DSP). The historical data learning module is implemented as a rolling database in a read-write storage area, and its rolling averaging algorithm runs as a software program module in the processor of the control unit 4. The PID parameter register is a random access memory area or non-volatile memory unit within the control unit 4. The input signals of each module are acquired through the analog input channel or digital input channel of the control unit 4, and the output commands are sent to the corresponding actuators through the analog output channel or digital output channel.

[0053] In some embodiments, such as Figure 1 and Figure 2As shown in (c), the pre-dissolving chamber 1 and the main dissolving chamber 2 are connected by a connecting pipe with a perforated plate 5. The perforated plate 5 has an opening ratio of 30% to 50% to homogenize the flow rate of the liquid flowing from the pre-dissolving chamber 1 into the main dissolving chamber 2, avoid short-circuit flow due to abrupt changes in the flow cross-section, and ensure a uniform transition of the liquid between the two chambers. The main dissolving chamber 2 and the maturation chamber 3 are connected by an overflow weir 6 with an adjustable weir crest height. The operator can adjust the weir crest height of the overflow weir 6 according to the required maturation time, thereby changing the residence time of the liquid in the main dissolving chamber 2, so that PAM solutions of different molecular weights or types can be fully dissolved and matured.

[0054] The pre-dissolving chamber 1 is equipped with a low-speed anchor-type pre-dispersion agitator 12, with a rotational speed ranging from 10 r / min to 30 r / min and a blade tip linear velocity not exceeding 1 m / s. The low-speed anchor-type pre-dispersion agitator 12 gently agitates the liquid at the bottom of the pre-dissolving chamber 1, preventing PAM particles from depositing at the bottom of the chamber and avoiding strong shearing to protect the integrity of the polymer chains. A liquid level sensor 18 is also installed on the wall of the pre-dissolving chamber 1, and the signal output of the liquid level sensor 18 is connected to the signal input of the control unit 4. The liquid level sensor 18 detects the liquid level in the pre-dissolving chamber 1 in real time and transmits the liquid level signal to the control unit 4 for logic judgments such as water injection control, material shortage protection, and liquid level interlocking. When the liquid level is lower than the set lower limit, the control unit 4 can trigger a material shortage protection command, stopping the screw feeder 11 and triggering an alarm.

[0055] In some embodiments, such as Figure 2 As shown in (a), the swirling negative pressure powder suction device 16 includes a Venturi nozzle and an induced draft fan 161 that cooperates with the Venturi nozzle. The air outlet of the induced draft fan 161 is connected to the air inlet of the Venturi nozzle through a pipeline. The discharge port of the screw feeder 11 is connected to the dry powder inlet of the Venturi nozzle at an angle of 30° to 60°. The ratio of the throat diameter of the Venturi nozzle to the discharge port diameter of the screw feeder 11 is 1:1.5 to 1:2.5. The swirling negative pressure powder suction device 16 has an anti-bridging conical disturbance member at the center of the swirling chamber. The cone angle of the conical disturbance member is 45°, its tip faces the direction of airflow, and its bottom is fixed to the inner wall of the throat of the Venturi nozzle. The control terminal of the induced draft fan 161 is connected to the control output terminal of the control unit 4. The control unit 4 is configured to control the air volume of the induced draft fan 161 and the rotation speed of the screw feeder 11, so that the air-powder mass ratio is maintained at 20:1 to 50:1.

[0056] During operation, the high-speed airflow generated by the induced draft fan 161 flows axially along the Venturi nozzle, forming a local negative pressure zone at the Venturi throat, which draws in the PAM dry powder quantitatively output by the screw feeder 11 from the dry powder inlet. The airflow, carrying dry powder particles, impacts the anti-bridging conical disturbance component at high speed, creating a swirling dispersion state. This ensures that the dry powder particles are fully dispersed into individual discrete particles before entering the pre-dissolving chamber 1, inhibiting the agglomeration of dry powder into fish-eye gel clusters from the source. Simultaneously, the anti-bridging conical disturbance component continuously disturbs the dry powder near the inlet, preventing bridging and arching at the inlet that could lead to material breakage. In some embodiments, the pore size of the microporous aeration tube 17 is 50 μm to 150 μm, the particle size of the bubbles generated by the microbubble generator 171 is 50 μm to 200 μm, and the aeration rate is 0.3 m³ / s. 3 / h~1.5m 3 / h. The micropore size is controlled within the range of 50μm to 150μm, which ensures small and uniform bubbles while avoiding micropore clogging. The microbubble generator 171 produces bubbles with a particle size of 50μm to 200μm. Microbubbles within this size range have a large specific surface area and a low rising velocity, which can form a stable microbubble layer near the liquid surface. This layer continuously carries and shears PAM particles falling into the liquid, promoting primary wetting of the particles before gravity settling. The aeration rate is selected as 0.3m³ / h. 3 / h~1.5m 3 / h, which can provide sufficient bubble density to suppress the formation of fish-eye gel clusters, and will not affect the powder dispersion effect of the vortex negative pressure powder suction device 16 due to violent turbulence of the liquid surface caused by excessive aeration.

[0057] The low-speed anchor-type pre-dispersion impeller 12 operates at a speed range of 10 r / min to 30 r / min, with a blade tip linear velocity not exceeding 1 m / s. This speed and linear velocity range ensures that the impeller only gently agitates the liquid at the bottom of the pre-dissolution chamber 1, preventing PAM particles from depositing at the bottom of the chamber and avoiding premature degradation of the polymer chains due to high-speed shearing. When the linear velocity does not exceed 1 m / s, the shear stress exerted by the impeller on the solution is far lower than the critical fracture stress of the PAM molecular chains, thus protecting the integrity of the molecular chains while ensuring particle suspension.

[0058] like Figure 2As shown in (b), the high-speed dispersion mode of the low-shear variable frequency stirring paddle 21 has a rotational speed range of 150 r / min to 300 r / min, and the low-speed maturation mode has a rotational speed range of 40 r / min to 80 r / min. In the high-speed dispersion mode, the rotational speed of 150 r / min to 300 r / min provides sufficient turbulent energy to break up the PAM agglomerates that are not yet fully wetted, promoting the rapid unfolding of molecular chains. In the low-speed maturation mode, the rotational speed of 40 r / min to 80 r / min maintains the overall homogeneous flow of the liquid, avoiding excessive shearing of the unfolded polymer chains, thereby achieving a balance between dispersion efficiency and viscosity retention.

[0059] The ultrasonic probe 24 operates at a frequency of 20kHz to 80kHz and has a power density of 0.5W / cm². 2 ~3.0W / cm 2 The number of ring arrays along the bottom of the main dissolution cavity 2 is 3-8, and the spacing between adjacent probes is 1-2 times the wavelength of the corresponding frequency ultrasound. Low-frequency ultrasound of 20kHz-80kHz can generate a stable cavitation effect. The microjets and shock waves released when the cavitation bubbles collapse can effectively break the gel layer on the surface of PAM particles, enhancing wetting and dispersion; the power density is controlled at 0.5W / cm². 2 ~3.0W / cm 2 This arrangement generates sufficient cavitation energy to aid dispersion while avoiding excessive power that could break polymer chains. Using a ring array of 3-8 probes with an adjacent spacing of 1-2 times the wavelength ensures a uniform sound field distribution within the main dissolution cavity 2, preventing standing wave dead zones or energy concentration points. This guarantees that PAM particles at different locations within the cavity are subjected to ultrasonic cavitation, thereby improving overall dissolution uniformity.

[0060] In some embodiments, the online concentration sensor 13 has a detection range of 0.05%~0.5%w / v, a detection accuracy better than ±0.005%w / v, and a sampling period of no more than 2s; the online viscometer 22 has a detection range of 1mPa·s~50000mPa·s, a detection accuracy better than ±2%FS, and a sampling period of no more than 5s.

[0061] The parameter limitations of the online concentration sensor 13 and online viscometer 22 described above are merely examples, intended to assist in the selection of the online concentration sensor 13 and online viscometer 22. Preferably, the online concentration sensor 13 can be a near-infrared transmission type online concentration sensor, and the online viscometer 22 can be a rotary type online viscometer.

[0062] Example 2: This invention provides a PAM flocculant intelligent dissolution control method based on any of the PAM flocculant intelligent dissolution control devices in Embodiment 1. Before implementation, this control method can perform sensor calibration and parameter calibration steps. Understandably, sensor calibration and parameter calibration are fundamental to ensuring the accurate and reliable operation of the control method and are standard pre-operations in the field. Sensor calibration eliminates systematic errors introduced by manufacturing tolerances, installation deviations, and environmental factors in various detection elements, ensuring the authenticity and consistency of feedback signals such as concentration, viscosity, conductivity, and temperature. Parameter setting allows for the configuration of reasonable adjustment parameters and threshold values ​​for the control unit based on process requirements such as target solution concentration and viscosity, enabling the device to achieve accurate and stable intelligent control under different operating conditions. This embodiment provides an exemplary sensor calibration and parameter calibration step as follows.

[0063] For sensor calibration: After the device is installed, each online sensor is calibrated first: the online concentration sensor 13 uses a pre-configured calibration model supplemented with on-site single-point calibration, and the zero-point offset is measured by statically immersing the probe with a PAM standard solution with a concentration of 0.20% w / v; the rotary online viscometer 22 is calibrated at multiple points using silicone oil standard solutions at 100 mPa·s, 500 mPa·s, and 2000 mPa·s, and the linearity after calibration is better than ±1%FS; the conductivity sensor 31 is calibrated at a single point using a standard KCl solution at 25℃ with a concentration of 1413 μS / cm; the temperature sensor 23 is calibrated at two points using an ice-water bath at 0℃ and a boiling water bath at 100℃.

[0064] For parameter settings, the following operating parameters are set in control unit 4: target solution concentration 0.20%w / v, target viscosity 280mPa·s (equivalent at 25℃); concentration loop base proportional gain. =8.0, Basic Integral Time =60s; viscosity ring =5.0、 =90s, differential time =5s; Viscosity slope switching threshold Initial value is set to 5 mPa·s / min; temperature compensation sub-model parameters Take 0.025℃ -1 Calibration reference temperature Use 25℃; use a reference conductivity of 1200μS / cm.

[0065] When this control method is implemented after sensor calibration and parameter calibration are completed, it can be configured to be executed through control unit 4, such as... Figure 5 As shown, it includes the following steps S501-S505.

[0066] S501: Control the inlet electric regulating valve 15 to inject water into the pre-dissolving chamber 1 to the set liquid level, and control the microbubble generator 171 to start pre-aeration.

[0067] In specific implementation, the water inlet electric regulating valve 15 is started to inject water into the pre-dissolving chamber 1 to the set liquid level (60% in this embodiment), and the ultra-micro bubble generator 171 is started to pre-aerate for 2 minutes to form a uniform micro bubble field in the chamber, creating interface conditions for subsequent dry powder wetting.

[0068] S502: After pre-aeration is completed, control the start of the blower 161 and the screw feeder 11 to introduce PAM dry powder into the pre-dissolving chamber 1 through the swirling negative pressure powder suction device 16 in a pneumatic dispersion manner. Based on the set target concentration and the PAM mass concentration in the pre-dissolving chamber detected in real time by the online concentration sensor 13, adjust the speed of the screw feeder 11 and the opening of the water inlet electric regulating valve 15 to maintain the air-powder mass ratio at 20:1~50:1 and the water-powder mass ratio at 300:1~800:1.

[0069] In step S502, during the adjustment of the screw feeder 11 speed and the opening of the inlet electric regulating valve 15, the concentration deviation |ΔC| between the target concentration and the real-time concentration detection value is calculated. When |ΔC| is less than or equal to the preset concentration deviation value, the adjustment is performed according to the preset basic PID parameters. When |ΔC| is greater than the preset concentration deviation value, the proportional gain is adjusted to m times the basic proportional gain for accelerated adjustment, where m is a positive number greater than 1. The basic proportional gain is updated according to the preset cycle. Basic Integral Time Switching threshold with viscosity slope .

[0070] In practice, the induced draft fan 161 and the screw feeder 11 are started. The screw feeder 11 initially rotates at 30 r / min. The PAM dry powder falls into the liquid surface of the pre-dissolution chamber 1 through the swirling negative pressure powder suction device 16 in a pneumatic dispersion manner. The near-infrared transmission online concentration sensor 13 detects the mass concentration of PAM in the pre-dissolution chamber in real time. And feedback is sent to control unit 4.

[0071] Control unit 4 with concentration deviation Perform PID calculations on the input: when When ≤0.05%, follow =8.0、 =60s for normal adjustment; when ΔC>0.05%, switch to large deviation rapid adjustment mode, proportional gain according to =1.5 Accelerate the response, adjusting the response time to no more than 30 seconds. Based on this, the control unit 4 outputs the AO-1 frequency conversion signal to the screw feeder 11 and the AO-3 opening signal to the water inlet electric regulating valve 15, thereby adjusting the powder addition and water inlet to maintain the air-powder mass ratio at 20:150:1 (30:1 in this embodiment) and the water-powder mass ratio at 300:1~800:1 (500:1 in this embodiment), so that the concentration in the pre-dissolving chamber quickly approaches the target value and remains stable.

[0072] S503: After the material in the pre-dissolving chamber 1 flows into the main dissolving chamber 2 through the guide plate 5, the equivalent viscosity is calculated based on the solution viscosity detected in real time by the online viscometer 22 and the solution temperature detected in real time by the temperature sensor 23, using the built-in temperature compensation sub-model. .

[0073] In practice, the liquid enters the main dissolution chamber 2 through the guide plate 5, and the actual viscosity of the solution is detected in real time by the rotary online viscometer 22. According to the temperature compensation sub-model (This embodiment) =0.025℃ -1 , The equivalent viscosity was obtained after correction at 25℃. This eliminates the interference of water temperature fluctuations on viscosity interpretation.

[0074] S504: Based on equivalent viscosity Calculate the slope of the viscosity change rate. ,when Viscosity slope switching threshold greater than preset And when the duration is not less than the set first duration, switch the low-shear variable frequency stirring paddle 21 to high-speed dispersion mode and turn on the ultrasonic probe 24; when Less than When the duration is not less than the set second duration, the low-shear variable frequency stirring paddle 21 is switched to low-speed maturation mode and the ultrasonic probe 24 is turned off.

[0075] In this embodiment, the high-speed dispersion mode is that the low-shear variable frequency agitator 21 operates at a speed of 150 r / min to 300 r / min, and the low-speed maturation mode is that the low-shear variable frequency agitator 21 operates at a speed of 40 r / min to 80 r / min. n is a set positive number less than 1, and here n=1.5.

[0076] In practical implementation, control unit 4 calculates the slope of the viscosity change rate. And switch the stirring mode accordingly. When > (This embodiment takes) When the PAM molecular chains are rapidly expanding (p = 5 mPa·s / min) and the dispersion duration is not less than 30 s, it is determined that the PAM molecular chains are rapidly expanding and require enhanced dispersion. The low-shear variable frequency stirrer 21 is switched to high-speed dispersion mode (rotation speed 240 r / min), and the ultrasonic probe 24 is turned on (operating frequency 28 kHz, power density 2.0 W / cm³). 2 ), using cavitation energy to replace part of the mechanical shearing to enhance wetting and dispersion; when <0.1 When the dissolution is considered to be complete and the maturation stage is entered, the process is switched to low-speed maturation mode (60 r / min) and the ultrasonic probe 24 is turned off to protect the unfolded polymer chains from excessive shearing.

[0077] when Satisfying 0.1 ≤ ≤ When the viscosity change rate slope is between the switching threshold and the lower threshold, the control unit 4 determines that the current dissolution process is normal and there is no need to switch the stirring mode or ultrasonic state. It maintains the current rotation speed of the low-shear variable frequency stirring paddle 21 and the current on / off state of the ultrasonic probe 24, and continues to calculate at a set period (every 5 seconds). The value is continuously monitored until any of the above switching conditions are met. If the duration of this intermediate state exceeds the preset upper limit (10 minutes in this embodiment), the control unit 4 issues a prompt message to remind the operator to check whether there are any abnormalities in the raw materials or water quality.

[0078] S505: After the material in the main dissolving chamber 2 flows into the maturation chamber 3 through the overflow weir 6 for maturation, the equivalent concentration after ion strength correction is calculated based on the real-time detection of the outlet conductivity by the conductivity sensor 31 and the detection value by the online concentration sensor 13. When the equivalent concentration When the concentration is within the preset acceptable range, the electric discharge valve 32 is opened to output the finished liquid; when the equivalent concentration is within the acceptable range... When the material exceeds the preset acceptable range, the electric discharge valve 32 is closed and the solenoid valve on the return pipeline 34 is opened, so that the material returns to the pre-dissolution chamber 1 for re-dissolution.

[0079] In practice, the liquid feed enters the maturation chamber 3 through the overflow weir 6, and the low-speed agitator 33 runs at an axial flow velocity of 0.1 m / s to homogenize and mature the liquid feed. The conductivity sensor 31 detects the conductivity of the liquid, and the conductivity-concentration coupling correction module in the control unit 4 performs joint calculations to obtain the equivalent concentration corrected for ion strength. When the reading of conductivity sensor 31 deviates from the reference conductivity (1200 μS / cm in this embodiment) by no more than ±15%, and If the deviation from the target concentration does not exceed ±10%, the liquid output is deemed qualified, and the electric liquid output valve 32 is opened to output the finished liquid; otherwise, the electric liquid output valve 32 is closed and the solenoid valve on the return pipeline 34 is opened to allow the unqualified solution to flow back to the pre-dissolution chamber 1 for redissolution until the quality is qualified before it is output again.

[0080] In some embodiments, the control method further includes historical data learning and parameter self-tuning steps. Specifically, the historical data learning module built into the control unit 4 continuously updates the basic proportional gain Kp0, basic integral time Ti0, and viscosity slope switching threshold k0 using a 24-hour rolling average algorithm. The difference before and after the update is limited to within ±20%, and the update result is written back to the PID parameter register (corresponding to...). Figure 3 The PID parameters are written back (dashed line) to enable the device to continuously adapt to PAM batch differences and water quality drift during long-term operation.

[0081] In some embodiments, such as Figure 6 The diagram shown is a flowchart of the protection and operating condition adaptation operation provided in an embodiment of the present invention. During the entire dissolution process, i.e., during steps S501-S505 above, the control unit 4 executes the protection and operating condition adaptation operation, including steps S601-S604 as follows. It should be noted that steps S601-S604 are parallel steps.

[0082] S601: When the liquid level in the pre-dissolving chamber 1 is lower than the preset lower limit or the current of the screw feeder 11 is lower than the no-load value after three consecutive sampling cycles, the material cut-off protection is triggered.

[0083] S602: When the gas source pressure of the microbubble generator 171 is lower than the set gas source pressure value, the gas supply interruption protection is triggered.

[0084] S603: When the output value of the online viscometer 22 changes abruptly beyond the set threshold within a set time, the sensor is determined to be abnormal and an audible and visual alarm is triggered.

[0085] S604: When the temperature of the prepared water is found to be lower than the set temperature value, control the heating device of the pre-dissolving chamber 1 to operate so that the temperature of the prepared water is maintained within the preset temperature threshold range.

[0086] Steps S601-S603 above are designed to achieve fault protection. In specific implementation, when the control unit 4 detects that the liquid level in the pre-dissolving chamber 1 is lower than the set lower limit or the current of the screw feeder 11 is lower than the no-load value for three consecutive sampling cycles, the material cut-off protection is triggered; when the gas source pressure of the microbubble generator 171 is lower than 0.15MPa, the gas cut-off protection is triggered; when the output value of the rotary online viscometer 22 changes abruptly by more than ±30% within 5 seconds, the sensor is determined to be abnormal, and the system automatically switches to the open-loop protection mode estimated by the temperature-concentration model and outputs an audible and visual alarm via DO-3. Step S604 above is designed to achieve working condition adaptation. For example, when the temperature of the prepared water is found to be lower than 15℃, the heating device of the pre-dissolving chamber 1 is controlled to operate, so that the temperature of the prepared water is maintained within the range of 15℃~25℃.

[0087] In some embodiments, such as Figure 7 The diagram shown is another flowchart of a PAM flocculant intelligent dissolution control method provided by an embodiment of the present invention. This PAM flocculant intelligent dissolution control method includes the following steps: S701: Start water intake, pre-aeration, and fill water to 60% level; S702: Start the induced draft fan and screw feeder to pneumatically disperse and feed powder; S703: NIR concentration sensor for real-time detection and calculation. ; S704: Judgment Is >0.05% true? S705: If >0.05%, activate the large deviation rapid adjustment mode. =1.5 ; S706: If ≤0.05%, based on , Perform routine adjustments; S707: Material overflows into the main dissolving chamber, detected by viscometer 22. Temperature compensation ; S708: Calculate the viscosity slope ; S709: Judgment > And whether the duration is ≥30s; S710: If > And the duration is ≥30s, switch to high-speed dispersion mode and turn on the ultrasonic probe according to the material; S711: If ≤ Or if the duration is <30s, then judge. <0.1 And whether the duration is ≥60s; S712: If <0.1 And the duration is ≥60s, then the stirring is switched to low-speed cooking mode and the ultrasonic probe is turned off; S713: If ≥0.1 If the duration is less than 60 seconds, maintain the current mode; S714: Material overflows into the curing chamber; conductivity is detected and coupled for correction. ; S715: Judgment Does the deviation from the target by >±10% or the conductivity deviation by >±15% qualify? S716: If If the deviation from the target is >±10% or the conductivity deviation is >±15%, close the outlet valve 32 and open the return pipe 34 to return the liquid to the pre-dissolution chamber; S717: If If the deviation from the target is ≤±10% and the conductivity deviation is ≤±15%, the electric discharge valve 32 will be opened to output the finished liquid. S718: Determine if the time since the last learning session is ≥24 hours; S719: If the last learning session was ≥24 hours ago, the historical data learning module will be updated. , , The difference in parameters before and after the update is limited to within ±20%; S720: Determines whether a protection condition has been triggered. Protection conditions include material interruption, gas interruption, sensor malfunction, and liquid level malfunction. S721: If the protection condition is triggered, enter the corresponding protection mode and trigger an audible and visual alarm; S722: If the protection condition is not triggered, return to step S703 and repeat.

[0088] The above control process is a continuous operation cycle of the device. When the system receives a stop command, it will sequentially shut down the screw feeder 11, the induced draft fan 161, the ultrasonic probe 24, the low-shear variable frequency agitator 21, the low-speed propulsion agitator 33, and the microbubble generator 171. After the solution in each chamber is drained, the electric inlet regulating valve 15, the electric outlet valve 32, and the solenoid valve on the return pipeline 34 will be closed to complete the shutdown process. This control method achieves fully automated, unattended operation of the entire PAM flocculant dissolution process through closed-loop adjustment of concentration and viscosity dual parameters, adaptive switching of the dissolution stage, online parameter self-learning, and multiple fault protection mechanisms. It effectively solves the problems of large concentration fluctuations, insufficient dissolution, severe molecular chain shearing, and high labor intensity existing in traditional manual preparation methods, ensuring the stability and consistency of the finished liquid quality.

[0089] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the present invention, and the patent protection scope of the present invention should be defined by the claims.

Claims

1. A smart dissolving device for PAM flocculant, characterized in that, It includes a pre-dissolving chamber (1), a main dissolving chamber (2), and a maturation chamber (3) arranged sequentially along the material flow direction, as well as a control unit (4); The top of the pre-dissolving chamber (1) is provided with a swirling negative pressure powder suction device (16), which is connected to the discharge port of the screw feeder (11) at the bottom of the dry powder silo; a water inlet flow meter (14) and an electric water inlet regulating valve (15) are installed sequentially along the water flow direction on the water inlet pipe at the bottom of the pre-dissolving chamber (1); an online concentration sensor (13) is installed on the chamber wall; and a microporous aeration pipe (17) is arranged circumferentially at the bottom of the chamber. The air inlet end of the microporous aeration pipe (17) is connected to an ultra-microbubble generator (171). The main dissolution chamber (2) is equipped with a low-shear variable frequency stirring paddle (21), an online viscometer (22) and a temperature sensor (23) are installed on the chamber wall, and an ultrasonic probe (24) is evenly distributed along the annular array at the bottom of the chamber. The ripening chamber (3) is equipped with a low-speed stirring paddle (33), and a conductivity sensor (31) and an electric liquid outlet valve (32) are sequentially arranged along the flow direction on the outlet pipe. The downstream of the electric liquid outlet valve (32) is connected to the inlet of the pre-dissolving chamber (1) through a return pipe (34), and a solenoid valve is provided on the return pipe (34). The signal output terminals of the online concentration sensor (13), online viscometer (22), temperature sensor (23), and conductivity sensor (31) are respectively connected to the corresponding signal input terminals of the control unit (4); the control output terminals of the control unit (4) are respectively connected to the corresponding control terminals of the screw feeder (11), the electric water inlet regulating valve (15), the low shear frequency conversion stirring paddle (21), the ultrasonic probe (24), the electric liquid outlet valve (32), and the solenoid valve on the return pipeline (34); The control unit (4) is configured to: Obtain the real-time concentration detection value of the online concentration sensor (13), and adjust the rotation speed of the screw feeder (11) and the opening degree of the water inlet electric regulating valve (15) according to the target concentration and the real-time concentration detection value. The real-time viscosity detection value of the online viscometer (22) and the real-time temperature detection value of the temperature sensor (23) are obtained. The real-time viscosity is compensated by temperature to obtain the equivalent viscosity. Based on the target equivalent viscosity and the real-time equivalent viscosity detection value, the rotation speed of the low-shear variable frequency stirring paddle (21) and the power of the ultrasonic probe (24) are adjusted. The real-time conductivity detection value of the conductivity sensor (31) is obtained, the quality of the liquid is judged based on the conductivity detection value, and the opening and closing of the electric liquid outlet valve (32) and the solenoid valve on the return pipeline (34) are driven.

2. The intelligent dissolving device for PAM flocculant according to claim 1, characterized in that, The pre-dissolving chamber (1) is connected to the main dissolving chamber (2) through a connecting pipe with a guide plate (5), and the main dissolving chamber (2) is connected to the maturation chamber (3) through an overflow weir (6) with adjustable weir top height; the pre-dissolving chamber (1) is equipped with a low-speed anchor-type pre-dispersion stirring paddle (12), and a liquid level sensor (18) is also installed on the chamber wall. The signal output terminal of the liquid level sensor (18) is connected to the signal input terminal of the control unit (4).

3. The intelligent dissolving device for PAM flocculant according to claim 1, characterized in that, The swirling negative pressure powder suction device (16) includes a Venturi nozzle and an induced draft fan (161) that cooperates with the Venturi nozzle. The ratio of the throat diameter of the Venturi nozzle to the discharge port diameter of the screw feeder (11) is 1:1.5 to 1:2.

5. The dry powder inlet axis of the Venturi nozzle forms an angle of 30° to 60° with the airflow direction. The swirling cavity of the swirling negative pressure powder suction device (16) is provided with an anti-bridging conical disturbance component. The control end of the induced draft fan (161) is connected to the control output end of the control unit (4). The control unit (4) is configured to control the air volume of the induced draft fan (161) and the rotation speed of the screw feeder (11) to maintain the air-powder mass ratio at 20:1 to 50:

1.

4. The intelligent dissolving device for PAM flocculant according to claim 2, characterized in that, The microporous aeration tube (17) has a pore size of 50μm to 150μm, and the microbubble generator (171) produces bubbles with a particle size of 50μm to 200μm and an aeration rate of 0.3m³. 3 / h~1.5m 3 / h; the rotational speed range of the low-speed anchor-type pre-dispersion stirring paddle (12) is 10r / min~30r / min, and the linear velocity at the blade tip does not exceed 1m / s.

5. The intelligent dissolving device for PAM flocculant according to claim 1, characterized in that, The high-speed dispersion mode of the low-shear variable frequency stirring paddle (21) has a rotation speed range of 150 r / min to 300 r / min, and the low-speed maturation mode has a rotation speed range of 40 r / min to 80 r / min.

6. The intelligent dissolving device for PAM flocculant according to claim 5, characterized in that, The ultrasonic probe (24) operates at a frequency of 20kHz to 80kHz and has a power density of 0.5W / cm². 2 ~3.0W / cm 2 The array consists of 3 to 8 probes, and the distance between adjacent probes is 1 to 2 times the wavelength of the corresponding frequency ultrasound.

7. The intelligent dissolving device for PAM flocculant according to claim 1, characterized in that, The control unit (4) incorporates a temperature compensation sub-model, a historical data learning module, a conductivity-concentration coupling correction module, and a protection logic module; wherein: The temperature compensation sub-model responds to the measured viscosity output by the online viscometer (22). and the real-time temperature output by the temperature sensor (23) According to the formula The equivalent viscosity was calculated. ,in To correct the parameters, The preset calibration reference temperature; The historical data learning module responds to the input, time-continuous running data and calculates the updated base proportional gain using a rolling average algorithm. Basic Integral Time Switching threshold with viscosity slope The parameter difference before and after the update is limited to within the set parameter difference threshold range, and the updated parameters are written back to the PID parameter register. The conductivity-concentration coupling correction module responds to the real-time conductivity output by the conductivity sensor (31) and the real-time concentration output by the online concentration sensor (13) by performing ion strength coupling calculations to obtain the corrected equivalent concentration. ; in response to the real-time conductivity deviating from the reference conductivity by more than a first set range or the equivalent concentration If the concentration deviates from the target concentration by more than the second set range, a reflux reconstitution command is output to the execution output terminal of the control unit (4), which controls the electric liquid outlet valve (32) to close and controls the solenoid valve on the reflux pipeline (34) to open. The protection logic module responds to the status signals of the liquid level sensor (18), screw feeder (11), microbubble generator (171) and online viscometer (22). When the liquid level in the pre-dissolving chamber (1) is detected to be lower than the set lower limit or the current of the screw feeder (11) is lower than the no-load value for three consecutive sampling cycles, it outputs a material cut-off protection command to the execution output terminal of the control unit (4). The execution output terminal controls the screw feeder (11) to stop running and triggers an audible and visual alarm. When the gas source pressure of the microbubble generator (171) is detected to be lower than the set gas source pressure value, the gas cut-off protection command is output to the execution output terminal of the control unit (4), and the execution output terminal controls the microbubble generator (171) to stop running and triggers an audible and visual alarm. When the output value of the online viscometer (22) is detected to change abruptly within a set time and exceed the set change threshold, a sensor abnormality protection command is output to the execution output terminal of the control unit (4), and the execution output terminal triggers an audible and visual alarm.

8. A method for intelligent dissolution control of PAM flocculant using the apparatus described in any one of claims 1 to 7, characterized in that, The control method includes: Control the electric regulating valve (15) to inject water into the pre-dissolving chamber (1) to the set liquid level, and control the microbubble generator (171) to start pre-aeration; After pre-aeration is completed, the blower (161) and screw feeder (11) are started to introduce PAM dry powder into the pre-dissolution chamber (1) by pneumatic dispersion through the swirling negative pressure powder suction device (16). Based on the set target concentration and the PAM mass concentration in the pre-dissolution chamber detected in real time by the online concentration sensor (13), the speed of the screw feeder (11) and the opening of the water inlet electric regulating valve (15) are adjusted to maintain the air-powder mass ratio at 20:1~50:1 and the water-powder mass ratio at 300:1~800:

1. After the material in the pre-dissolving chamber (1) flows into the main dissolving chamber (2) through the guide plate (5), the equivalent viscosity is calculated based on the solution viscosity detected in real time by the online viscometer (22) and the solution temperature detected in real time by the temperature sensor (23) through the built-in temperature compensation sub-model. ; Based on the equivalent viscosity Calculate the slope of the viscosity change rate. ,when Viscosity slope switching threshold greater than preset When the duration is not less than the set first duration, the low-shear variable frequency stirring paddle (21) is switched to high-speed dispersion mode and the ultrasonic probe (24) is turned on. The high-speed dispersion mode is when the low-shear variable frequency stirring paddle (21) runs at a speed of 150 r / min to 300 r / min; when Less than When the duration is not less than the set second duration, the low shear frequency stirring paddle (21) is switched to low speed maturation mode and the ultrasonic probe (24) is turned off. n is a set positive number less than 1. The low speed maturation mode is when the low shear frequency stirring paddle (21) runs at a speed of 40r / min to 80r / min. After the material in the main dissolving chamber (2) flows into the maturation chamber (3) through the overflow weir (6) for maturation, the equivalent concentration after ion strength correction is calculated based on the real-time detection of the outflow conductivity by the conductivity sensor (31) and the detection value by the online concentration sensor (13). When the equivalent concentration When the product is within the preset acceptable range, the electric discharge valve (32) is opened to output the finished product; when the equivalent concentration... When the material exceeds the preset qualified range, the electric discharge valve (32) is closed and the solenoid valve on the return pipeline (34) is opened, so that the material returns to the pre-dissolution chamber (1) for re-dissolution.

9. The intelligent dissolution control method for PAM flocculant according to claim 8, characterized in that, During the adjustment of the screw feeder (11) speed and the opening of the inlet electric regulating valve (15), the concentration deviation |ΔC| between the target concentration and the real-time concentration detection value is calculated; when |ΔC| is less than or equal to the preset concentration deviation value, the adjustment is performed according to the preset basic PID parameters; when |ΔC| is greater than the preset concentration deviation value, the proportional gain is adjusted to m times the basic proportional gain for accelerated adjustment, where m is a positive number greater than 1; the basic proportional gain is updated according to the preset cycle. Basic Integral Time Switching threshold with viscosity slope .

10. The intelligent dissolution control method for PAM flocculant according to claim 8, characterized in that, The control method further includes: During the entire dissolution process, if the liquid level in the pre-dissolution chamber (1) is lower than the preset lower limit or the current of the screw feeder (11) is lower than the no-load value after three consecutive sampling cycles, the material cut-off protection is triggered. When the gas source pressure of the microbubble generator (171) is lower than the set gas source pressure value, the gas supply interruption protection is triggered. When the output value of the online viscometer (22) changes abruptly beyond the set threshold within a set time, the sensor is determined to be abnormal and an audible and visual alarm is triggered. When the temperature of the prepared water is lower than the set temperature value, the heating device of the pre-dissolving chamber (1) is controlled to operate so that the temperature of the prepared water is maintained within the preset temperature threshold range.

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