Spray dryer with particle state monitoring and control method

Abstract

The invention discloses a spray dryer with a particle state monitoring function and a control method. Two monitoring parts are arranged in a first air guide pipe and a second air guide pipe correspondingly, and two pressure sensors are arranged on a first flange ring and a second flange ring correspondingly; the two material barrels are connected to the two pressure sensors in a surrounding and hanging mode and can move in the vertical direction. According to the spray dryer with the particle state monitoring function and the control method, the equivalent particle size of material particles is obtained through calculation according to the airflow speed obtained through testing of the anemograph and the particle speed difference obtained through testing of the two first electrode rings; the two material barrel assemblies are arranged corresponding to the cyclone separator and the dryer body respectively, the effect of the difference between the inner air pressure and the outer air pressure on the material barrels can be converted through real-time air pressure data of the inner air pressure gauge and the outer air pressure gauge, in the process of calculating the weight of materials in the material barrels, the influence of the air pressure difference is deducted, and the weight of the materials is corrected in real time.

Description

Technical Field

[0001] The present invention relates to the field of spray drying, and particularly to a spray dryer with particle state monitoring and a control method. Background Art

[0002] A spray dryer is a very important device that mainly utilizes spray technology to effectively convert various liquid materials into dry powder form. During operation, the spray dryer atomizes the liquid material by using a high-pressure nozzle to form fine droplets. The fine droplets will then rapidly evaporate the moisture therein under the action of hot air flow, and finally obtain dry solid particles. Due to its efficient and convenient drying ability, this device has been widely used in many fields such as the food industry, chemical industry, and pharmaceutical industry. It can handle various types of liquid materials, including but not limited to emulsions, solutions, and suspensions, etc., providing great convenience and efficiency improvement for these industries.

[0003] Currently, the monitoring methods for the working state of the spray dryer mainly include temperature monitoring, pressure monitoring, flow monitoring, particle size analysis, and humidity monitoring. Temperature monitoring detects the temperatures at different parts inside the dryer to ensure that the material is dried at the correct temperature and avoid overheating or insufficient temperature. Pressure monitoring monitors the pressure changes inside the dryer to ensure the stability and efficiency of the spray drying process. Flow monitoring measures the liquid flow rate and gas flow rate entering the dryer to ensure that their ratio is appropriate. Particle size analysis analyzes the particle size distribution of the dried product to ensure that the product quality meets the requirements. Humidity monitoring detects the humidity of the gas at the outlet to ensure the drying effect.

[0004] The conventional particle size analysis test process is slow and more unable to achieve online monitoring. Then, during the entire drying process, the monitoring of the particle size of the material is lacking. And in the conventional production process, the online monitoring of the weight output of the material is impossible, and for the method of conducting humidity tests on the divided air outlets at various positions, the structure is complex and errors are easily generated. Summary of the Invention

[0005] The main object of the present invention is to provide a spray dryer with particle state monitoring and a control method, aiming to solve the problem of difficult online testing of the dry particle state during the spray drying process.

[0006] To achieve the above object, the present invention provides a spray dryer with particle state monitoring, including:

[0007] A dryer main body, with a first air duct led out, a first flange ring is arranged at the bottom of the dryer main body, and the dryer main body is connected to an external hot air part and an atomization part;

[0008] A cyclone separator is connected to the dryer body through the first air duct and is provided with a second air duct for export. A second flange ring is arranged at the bottom of the cyclone separator;

[0009] Two monitoring parts are respectively arranged in the first air duct and the second air duct. The monitoring part includes an anemometer and two pairs of first electrode rings arranged in pairs. The first electrode rings are used to obtain induced electrical signals, and the two first electrode rings are used to calculate and obtain the particle velocity;

[0010] Two bucket assemblies. The bucket assembly includes a bucket, a pressure sensor, an internal barometer and an external barometer. The two pressure sensors are respectively arranged on the first flange ring and the second flange ring. The two buckets are respectively surrounded and hung on the two pressure sensors and can move in the vertical direction. The internal barometer and the external barometer respectively measure the air pressure inside and outside the bucket;

[0011] A controller controls the internal barometer, the external barometer, the pressure sensor, the anemometer and the first electrode ring.

[0012] Further, the bottom end of the dryer body is a detachable transition cylinder. The bucket is installed on the transition cylinder, and a buffer pad is arranged at the connection position at the top of the transition cylinder.

[0013] Further, a second electrode ring which is connected and controlled by the controller is arranged on the inner wall of the transition cylinder.

[0014] Further, an ultrasonic probe which is connected and controlled by the controller is arranged at the top inside the bucket or inside the transition cylinder. The detection direction of the ultrasonic probe points to the bottom of the bucket, and a vibration motor which is connected and controlled by the controller is arranged on the bucket.

[0015] Further, the anemometers on the first air duct and the second air duct are both detachable.

[0016] Further, the pressure sensor is annular.

[0017] The present invention also provides a control method, which is applied to the above spray dryer with particle state monitoring and includes:

[0018] S1. Real-time obtain the first pressure sensing data of the pressure sensor on the dryer body, and calculate and obtain the first real-time gross material weight;

[0019] S2. Obtain the first air pressure sensing data of the internal barometer and the external barometer on the dryer body, and correct the first real-time gross material weight to obtain the first real-time material weight;

[0020] S3. Obtain the first real-time induction data of the two first flange rings on the first air duct, and calculate to obtain the first real-time particle velocity;

[0021] S4. Obtain the first real-time air flow velocity of the anemometer on the first air duct;

[0022] S5. Convert and obtain the first real-time equivalent particle size data according to the first real-time particle velocity and the first real-time air flow velocity.

[0023] Further, after the step of S5 includes:

[0024] S601. Obtain the set time interval, and calculate the first cumulative material weight and the first cumulative charge within the set time interval according to the first real-time material weight and the first real-time induction data;

[0025] S602. Obtain the average equivalent particle size data according to the equivalent particle size data within the set time interval;

[0026] S603. Calculate the ratio between the first cumulative charge and the first cumulative material weight, and evaluate the moisture content in the drying air flow by weighted combination with the average equivalent particle size data.

[0027] Further, after the step of S5 includes:

[0028] S701. Real-time obtain the second pressure sensing data of the pressure sensor on the cyclone separator, and calculate to obtain the second real-time gross material weight;

[0029] S702. Obtain the second air pressure sensing data of the internal barometer and the external barometer on the cyclone separator, and correct the second real-time gross material weight to obtain the second real-time material weight;

[0030] S703. Calculate the real-time material output according to the first real-time material weight and the second real-time material weight.

[0031] Further, an ultrasonic probe connected and controlled by the controller is provided at the top inside the material bucket, the detection direction of the ultrasonic probe points to the bottom of the material bucket, a vibration motor connected and controlled by the controller is provided on the material bucket, and after the step of S2 includes:

[0032] S801. Calculate the total material weight according to the first real-time material weight;

[0033] S802. After controlling the vibration motor to work, obtain the sensing data of the ultrasonic probe and calculate to obtain the material stacking height;

[0034] S803. Evaluate the product state of the material in the bucket on the dryer body according to the total weight of the material and the stacking height of the material.

[0035] The spray dryer and control method with particle state monitoring provided by the present invention calculate the equivalent particle size of the material particles through the air flow velocity obtained by testing with an anemometer and the particle velocity difference obtained by testing with two first electrode rings; two bucket assemblies are respectively arranged corresponding to the cyclone separator and the dryer body. Through the real-time air pressure data of the internal air pressure gauge and the external air pressure gauge, the effect of the difference between the internal and external air pressures on the bucket can be converted. During the process of calculating the weight of the material in the bucket, the influence of the air pressure difference is deducted, and the weight of the material is corrected in real time; through the first electrode ring, the cumulative charge of the material within a certain time range can also be obtained. Combining the weight data and the equivalent particle size of the material within this time range, the moisture content in the air flow passing through the monitoring part can also be converted and monitored. Description of the Drawings

[0036] Figure 1 is a schematic diagram (three-dimensional schematic diagram) of the spray dryer with particle state monitoring according to the first embodiment of the present invention;

[0037] Figure 2 is a cross-sectional schematic diagram of the bucket assembly in the spray dryer with particle state monitoring according to the first embodiment of the present invention;

[0038] Figure 3 is a schematic diagram (front view) of the spray dryer with particle state monitoring according to the first embodiment of the present invention;

[0039] Figure 4 is an installation schematic diagram of the monitoring part in the spray dryer with particle state monitoring according to the first embodiment of the present invention.

[0040] The realization, functional features and advantages of the object of the present invention will be further described in conjunction with the embodiments with reference to the drawings. Detailed Embodiments

[0041] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0042] Those skilled in the art can understand that, unless specifically stated, the singular forms "a", "an", "the", "above-mentioned" and "said" used herein may also include the plural forms. It should be further understood that the term "comprising" used in the description of the present invention means the presence of the described features, integers, steps, operations, elements, units, modules and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, units, modules, components and / or their groups. It should be understood that when we say an element is "connected" or "coupled" to another element, it can be directly connected or coupled to other elements, or there may also be intermediate elements. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The phrase "and / or" used herein includes all or any unit and all combinations of one or more of the associated listed items.

[0043] Those skilled in the art can understand that, unless otherwise defined, all terms used herein (including technical terms and scientific terms) have the same meaning as the general understanding of those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with their meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as here.

[0044] Referring to Figures 1 to 4 , in an embodiment of the present invention, a spray dryer with particle state monitoring includes:

[0045] A dryer main body 100, a first air duct 110 is led out, a first flange ring 120 is arranged at the bottom of the dryer main body 100, and the dryer main body 100 is connected to an external hot air part 010 and an atomizing part 020;

[0046] A cyclone separator 200, which is connected to the dryer main body 100 through the first air duct 110 and a second air duct 210 is led out, and a second flange ring is arranged at the bottom of the cyclone separator 200;

[0047] Two monitoring parts 300 are respectively arranged in the first air duct 110 and the second air duct 210. The monitoring part 300 includes an anemometer 310 and two pairs of first electrode rings 320 arranged in pairs. The first electrode rings 320 are used to obtain induction electric signals, and the two first electrode rings 320 are used to calculate and obtain the particle velocity;

[0048] Two barrel assemblies 400, the barrel assembly 400 includes a barrel 410, a pressure sensor 420, an internal barometer 430 and an external barometer 440. The two pressure sensors 420 are respectively arranged on the first flange ring 120 and the second flange ring. The two barrels 410 are respectively surrounded and hung on the two pressure sensors 420 and are movable in the vertical direction. The internal barometer 430 and the external barometer 440 respectively test the air pressure inside and outside the barrel 410;

[0049] A controller controls the internal barometer 430, the external barometer 440, the pressure sensor 420, the anemometer 310 and the first electrode ring 320.

[0050] In the prior art, the conventional particle size analysis and testing process is slow, and online monitoring cannot be realized. During the entire drying process, the monitoring of the particle size of the material is missing; and in the conventional production process, the online monitoring of the weight output of the material cannot be realized. For the method of deriving and dividing the air flow at each position for humidity testing, the structure is complex and errors are easily generated.

[0051] In the present invention, a spray dryer with particle state monitoring mainly includes a dryer main body 100 and a cyclone separator 200. A barrel assembly 400 is provided at the lower part of both the dryer main body 100 and the cyclone separator 200 for collecting materials.

[0052] A first air duct 110 is led out from the dryer main body 100. The shape of the dryer main body 100 can refer to the common shapes in the current prior art, and no specific limitation is made. A first flange ring 120 is arranged at the bottom of the dryer main body 100. The dryer main body 100 is connected to an external hot air part 010 and an atomizing part 020. The forms of the hot air part 010 and the atomizing part 020 can refer to the common shapes in the current prior art, and no specific limitation is made. The connected hot air part 010 is mainly used to provide a drying air flow with a set temperature and a set flow rate, so as to provide a drying effect, which can be air or other inert gases. The atomizing part 020 receives the material fluid and outputs it as material droplets. During the process of the droplets contacting the drying air flow, the material droplets are dried into material particles. The combination and cooperation methods among the above dryer main body 100, atomizing part 020 and hot air part 010 are not limited, and are based on the basic functions of spray drying. For example, the drying air flow provided by the hot air part 010 can enter from the upper part, lower part or side part of the dryer main body 100; the installation position of the atomizing part 020 can also be the upper part, lower part or side part of the dryer main body 100.

[0053] The cyclone separator 200 is connected to the dryer main body 100 through the first air duct 110 and is provided with a second air duct 210. The model and size of the cyclone separator 200 are not limited, and specifically, it should be able to perform particle separation. A second flange ring is provided at the bottom of the cyclone separator 200.

[0054] Two monitoring units 300 are respectively arranged in the first air duct 110 and the second air duct 210. The monitoring unit 300 includes an anemometer 310 and two first electrode rings 320 arranged in pairs. The first electrode ring 320 is used to obtain an induced electrical signal, and the two first electrode rings 320 are used to calculate and obtain the particle velocity. Taking the monitoring unit 300 in the first air duct 110 as an example, considering that the collision of materials with each other in the dryer main body 100 and in the first air duct 110, or the collision with the inner wall structure, or the friction between the material and the air flow may cause the material to generate static charges. When the charged material particles pass through the two first electrode rings 320, static induction generates equal amounts of opposite charges on the outer surface of the first electrode ring 320, and due to the movement of the material particles, the induced charges and induced electric potentials generated on the first electrode ring 320 also fluctuate continuously; the fluctuations of the induced charge or induced electric potential signal reflect the parameter information of the logistics particles. When the material particles flow through the two first electrode rings 320, two similar electrostatic signals are induced. With appropriate information processing methods, the velocity of the material particles can be obtained. The form of the anemometer 310 can be diverse, and specifically, it should be able to measure the flow velocity of the drying air flow. There is a difference between the air flow velocity measured by the anemometer 310 and the particle velocity measured by the two first electrode rings 320. The specific reason is that the larger the mass of the material particles, the lower the particle velocity (measured by the two first electrode rings 320) is compared to the flow velocity (measured by the anemometer 310). Then, based on the above velocity difference, the equivalent particle size of the material particles can be calculated. At the same time, the data obtained by the first electrode ring 320 can also represent the drying degree of the material particles to a certain extent. In a humid environment, water molecules in the air will help conduct away the charges; under dry conditions, charges are more likely to accumulate, and the static electricity phenomenon is more significant. Specifically, through any one of the two first electrode rings 320 in the monitoring unit 300, the cumulative charge of the material within a certain time range can also be obtained. Combining the weight data of the material within this time range and the equivalent particle size, the moisture content in the air flow passing through the monitoring unit 300 can also be monitored by conversion. Among them, the weight data is monitored through the subsequent bucket assembly 400.

[0055] Two hopper assemblies 400 are respectively arranged corresponding to the cyclone separator 200 and the dryer main body 100. The hopper assembly 400 includes a hopper 410, a pressure sensor 420, an internal barometer 430 and an external barometer 440. The two pressure sensors 420 are respectively arranged on the first flange ring 120 and the second flange ring. The pressure sensor 420 is not limited to a ring shape and can also be arranged separately. For example, the pressure sensor 420 includes four sub-sensor structures and is arranged at intervals of 90 degrees on the upper surface of the first flange ring 120. The two hoppers 410 are respectively surrounded and hung on the two pressure sensors 420 and can move vertically. The hopper 410 is hung on the pressure sensor 420 (that is, the first flange ring 120). While a closed space is formed between the hopper 410 and the dryer main body 100, the hopper 410 can also move to a certain extent in the height direction. The above-mentioned closed characteristic provides a basis for the normal operation of the dryer main body 100, and the characteristic that the hopper 410 can move to a certain extent in the vertical direction provides a basis for the pressure sensor 420 to perform the weight test on the hopper 410. The formation of a seal between the hopper 410 and the dryer main body 100 can introduce appropriate sealing materials and sealing structures at corresponding positions, which is not the focus here. The weight of the hopper 410 and the materials therein acts on the pressure sensor 420, so that the sensing data obtained by the pressure sensor 420 can be converted into weight data, providing a basis for calculating the weight of the materials in the hopper 410. At the same time, the internal barometer 430 and the external barometer 440 respectively measure the air pressure inside and outside the hopper 410. Through the real-time air pressure data of the internal barometer 430 and the external barometer 440, the effect of the difference in internal and external air pressure on the hopper 410 can be calculated. Generally, the external air pressure is less than the internal air pressure of the hopper 410. During the process of calculating the weight of the materials in the hopper 410, the influence of the air pressure difference is deducted, and the weight of the materials calculated by the pressure sensor 420 is corrected in real time. In a typical structure, the hopper 410 includes a barrel main body part and a fixing ring part. The barrel main body part and the fixing ring part are detachably combined. When the two are combined, a seal is formed, and at the same time, the fixing ring part is fixed to the pressure sensor 420.

[0056] The controller controls the internal barometer 430, the external barometer 440, the pressure sensor 420, the anemometer 310 and the first electrode ring 320. The controller completes tasks such as data reception and control of the start and stop of operations. The controller can also perform data conversion work to obtain material quality data, equivalent particle size data and moisture conversion data.

[0057] In summary, the equivalent diameter of the material particles is calculated based on the air velocity obtained by the anemometer 310 and the difference in particle velocity obtained by the two first electrode rings 320; the two bucket assemblies 400 are respectively arranged corresponding to the cyclone separator 200 and the dryer main body 100. By the real-time air pressure data of the internal air pressure gauge 430 and the external air pressure gauge 440, the effect of the difference between the internal and external air pressures on the bucket 410 can be converted. During the process of calculating the weight of the material in the bucket 410, the influence of the air pressure difference is deducted, and the material weight is corrected in real time; through the first electrode ring 320, the cumulative charge of the material within a certain time range can also be obtained. Combining the weight data and the equivalent diameter of the material within this time range, the moisture content in the air flow at the position of the monitoring unit 300 can also be converted and monitored.

[0058] Referring to Figures 1 to 2 , in one embodiment, the bottom end of the dryer main body 100 is a detachable transition cylinder 130, the bucket 410 is installed on the transition cylinder 130, and a buffer pad is provided at the connection position at the top of the transition cylinder 130.

[0059] In this embodiment, through the action of the buffer pad, the vibration of the dryer main body 100 itself is not transmitted to the transition cylinder 130 as much as possible, providing a basis for the normal operation of the pressure sensor 420. The specific material of the buffer pad can be various types of polymer materials or foaming materials. The transition cylinder 130 can be fixed at the upper end by means of a flange.

[0060] In one embodiment, a second electrode ring that is connected and controlled by the controller is provided on the inner wall of the transition cylinder 130.

[0061] Similar to the setting and working mode of the foregoing first electrode ring 320, in this embodiment, considering that the collision of the materials with each other in the dryer main body 100 or with the inner wall of the dryer main body 100 or the friction between the materials and the air flow may cause the materials to generate static charges, the materials entering the bucket 410 have static charges. It is detected by the second electrode ring (the specific form of the electrostatic detection device can be various). In a humid environment, water molecules in the air will help to conduct away the charges; in dry conditions, the charges are more likely to accumulate and the electrostatic phenomenon is more significant. Therefore, the cumulative charge data obtained by the second electrode ring combined with the weight data obtained by the bucket assembly 400 at the bottom of the dryer main body 100 can reflect the drying effect in the dryer main body 100 to a certain extent. For example, if the ratio between the cumulative charge data and the weight data is too small, it indicates that the drying effect is not good.

[0062] Referring to Figure 2, in one embodiment, an ultrasonic probe 450 that is connected and controlled by the controller is provided at the top inside the material bucket 410 or inside the transition cylinder 130. The detection direction of the ultrasonic probe 450 points to the bottom of the material bucket 410, and a vibration motor that is connected and controlled by the controller is provided on the material bucket 410.

[0063] In this embodiment, after the ultrasonic wave emitted by the ultrasonic probe 450 is transmitted downward and collides with the material in the material bucket 410, it is reflected back to the ultrasonic probe 450. Furthermore, the controller can calculate and obtain the height of the material in the material bucket 410 through the relevant data transmitted by the ultrasonic probe 450. Correspondingly, a vibration motor is provided on the material bucket 410. When it is necessary to determine the stacking height of the material in the material bucket 410, the working of the vibration motor is used to remove the angle of repose of the material in the material bucket 410, and then the accurate stacking height can be obtained. It should be noted that the stacking height and weight data of the material in the material bucket 410 do not have exactly the same meaning. Due to different particle size distribution characteristics of the powder, materials with the same weight data have different stacking heights. Therefore, the combination of the stacking height and weight data can, conversely, determine the particle size distribution characteristics of the material in the bucket. It should be noted that similar transition cylinders 130, second electrode rings, and ultrasonic probes 450 can also be provided at the position of the cyclone separator 200 to achieve a similar effect. However, the drying degree of the material collected at the position of the dryer main body 100 can largely represent the drying degree of the material at the cyclone separator 200. Therefore, the design of the above similar structure can be omitted to reduce the complexity of the overall system.

[0064] In one embodiment, the anemometers 310 on the first air duct 110 and the second air duct 210 are both detachably provided.

[0065] In this embodiment, the anemometer 310 is set to be detachable for easy detection and maintenance, especially in the case where the material affects the normal operation of the anemometer 310. The installation method of the anemometer 310 can be various and is not limited.

[0066] In one embodiment, the pressure sensor 420 is annular.

[0067] In this embodiment, the annular pressure sensor 420 can obtain more accurate pressure sensing data during the interaction with the material bucket 410, and thus the credibility of the obtained material weight data after conversion is higher.

[0068] The present invention also provides a control method, which is applied to the above spray dryer with particle state monitoring, and includes:

[0069] S1. Obtain the first pressure sensing data of the pressure sensor 420 on the dryer main body 100 in real time, and calculate and obtain the first real-time gross weight of the material;

[0070] S2. Obtain the first air pressure sensing data of the internal barometer 430 and the external barometer 440 on the dryer main body 100, and correct the first real-time gross material weight to obtain the first real-time material weight;

[0071] S3. Obtain the first real-time induction data of the two first flange rings 120 on the first air duct 110, and calculate to obtain the first real-time particle velocity;

[0072] S4. Obtain the first real-time air flow velocity of the anemometer 310 on the first air duct 110;

[0073] S5. Convert and obtain the first real-time equivalent particle size data according to the first real-time particle velocity and the first real-time air flow velocity.

[0074] In this embodiment, in the steps of S1 and S2, the weight of the material bucket 410 and the material therein acts on the pressure sensor 420, so that the sensing data obtained by the pressure sensor 420 can be converted into weight data, providing a basis for calculating the weight of the material in the material bucket 410. At the same time, the internal barometer 430 and the external barometer 440 respectively measure the air pressure inside and outside the material bucket 410. Through the real-time air pressure data of the internal barometer 430 and the external barometer 440, the effect of the difference in the internal and external air pressures on the material bucket 410 can be calculated. Generally, the external air pressure is less than the internal air pressure of the material bucket 410. During the process of calculating the weight of the material in the material bucket 410, the influence of the air pressure difference is deducted, and the weight of the material calculated by the pressure sensor 420 is corrected in real time.

[0075] In steps S3 to S5, considering that the materials may generate static charges when colliding with each other in the dryer main body 100 and in the first air duct 110, or colliding with the inner wall structure, or due to the friction between the materials and the air flow. When the charged material particles pass through the two first electrode rings 320, static induction causes equal amounts of opposite charges to be generated on the outer surface of the first electrode rings 320. Due to the movement of the material particles, the induced charges and induced electric potentials generated on the first electrode rings 320 also fluctuate continuously; the fluctuations of the induced charge or induced electric potential signals reflect the parameter information of the material particles. When the material particles flow through the two first electrode rings 320, two similar static electricity signals are induced. With appropriate information processing methods, the speed of the material particles can be obtained. The form of the anemometer 310 can be diverse, specifically subject to the ability to measure the flow rate of the drying air flow. There is a difference between the air flow speed obtained by testing with the anemometer 310 and the particle speed obtained by testing with the two first electrode rings 320. The specific reason is that the larger the mass of the material particles, the lower the particle speed (obtained by testing with the two first electrode rings 320) compared to the air flow speed (obtained by testing with the anemometer 310). Then, based on the above speed difference, the equivalent particle size of the material particles can be calculated.

[0076] In one embodiment, after the step of S5, it includes:

[0077] S601. Obtain the set time interval, and calculate the first cumulative material weight and the first cumulative charge within the set time interval according to the first real-time material weight and the first real-time induction data;

[0078] S602. Obtain the average equivalent particle size data according to the equivalent particle size data within the set time interval;

[0079] S603. Calculate the ratio between the first cumulative charge and the first cumulative material weight, and evaluate the moisture content in the drying air flow by weighted combination with the average equivalent particle size data.

[0080] In this embodiment, in step S601, the set time interval should not be too long or too short, and about one minute is appropriate. In step S602, the calculation method of the average equivalent particle size data can be directly taking the average value or adding other weighting methods, etc. Considering that water molecules in the air can help conduct away charges; under dry conditions, charges are more likely to accumulate and the static electricity phenomenon is more significant. At the same time, the smaller the particles, the more intense the generation of static electricity. Therefore, combining the first cumulative material weight and the average equivalent particle size data can perform a predictive calculation on the first cumulative charge. When there is a large deviation between the measured first cumulative charge and the predicted calculated value, the working state of the entire spray dryer, that is, the humidity of the drying air flow, can be judged.

[0081] In one embodiment, after the step of S5, the following steps are included:

[0082] S701. Obtain the second pressure sensing data of the pressure sensor 420 on the cyclone separator 200 in real time, and calculate to obtain the second real-time gross material weight;

[0083] S702. Obtain the second air pressure sensing data of the internal barometer 430 and the external barometer 440 on the cyclone separator 200, and correct the second real-time gross material weight to obtain the second real-time material weight;

[0084] S703. Calculate the real-time material output according to the first real-time material weight and the second real-time material weight.

[0085] In this embodiment, in the steps of S701 and S702, the specific process and purpose may be the same as those of S1 and S2, but specifically, one is the material weight test collected at the position of the dryer main body 100, and the other is the material weight test collected at the position of the cyclone separator 200. The first real-time material weight and the second real-time material weight obtained at the two positions respectively can obtain the real-time material output of the entire spray dryer. According to the real-time material output and the speed of the input material in the dryer main body 100, it can also be judged whether the entire spray dryer is working properly.

[0086] In one embodiment, an ultrasonic probe 450 connected and controlled by the controller is arranged at the top inside the material bucket 410 or inside the transition cylinder 130, the detection direction of the ultrasonic probe 450 points to the bottom of the material bucket 410, and a vibration motor connected and controlled by the controller is arranged on the material bucket 410. After the step of S2, the following steps are included:

[0087] S801. Calculate the total material weight according to the first real-time material weight;

[0088] S802. After controlling the vibration motor to work, obtain the sensing data of the ultrasonic probe 450 and calculate to obtain the material stacking height;

[0089] S803. Evaluate the product state of the material in the material bucket 410 on the dryer main body 100 according to the total material weight and the material stacking height.

[0090] In this embodiment, in step S801, according to the first real-time material weight, the total material weight of the material in the material bucket 410 on the dryer main body 100 can be calculated cumulatively.

[0091] In steps S802 and S803, a vibration motor is correspondingly provided on the barrel 410. When it is necessary to determine the stacking height of the material in the barrel 410, the vibration motor is operated to remove the repose angle of the material in the barrel 410, thereby obtaining an accurate stacking height. The ultrasonic wave emitted by the ultrasonic probe 450 is transmitted downward and collides with the material in the barrel 410, and then is reflected back to the ultrasonic probe 450, and then the controller can calculate the height of the material in the barrel 410 through the relevant data transmitted by the ultrasonic probe 450. It should be noted that the stacking height of the material in the barrel 410 is not exactly the same as the total weight of the material. Due to the different particle size distribution characteristics of the powder, the materials with the same total weight have different stacking heights. Therefore, the combination of the stacking height and the total weight of the material can in turn determine the particle size distribution characteristics of the material in the barrel, and then the product state is calibrated.

[0092] In summary, the spray dryer and control method with particle state monitoring provided by the present invention calculates the equivalent particle size of the material particles through the air flow velocity obtained by the anemometer 310 test and the particle velocity difference obtained by the two first electrode rings 320 tests; the two barrel assemblies 400 are respectively arranged corresponding to the cyclone separator 200 and the dryer body 100, and the real-time air pressure data of the internal barometer 430 and the external barometer 440 can be used to convert the effect of the difference in internal and external air pressure on the barrel 410. In the process of calculating the weight of the material in the barrel 410, the influence of the air pressure difference is deducted, and the material weight is corrected in real time; the first electrode ring 320 can also be used to obtain the accumulated charge of the material within a certain time range, and combined with the weight data of the material within this time range and the equivalent particle size, the moisture content in the airflow passing through the monitoring unit 300 can also be converted and monitored.

[0093] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A spray dryer with particle state monitoring, characterized in that: include: The dryer body is provided with a first air guide pipe, a first flange ring is provided at the bottom of the dryer body, and the dryer body is connected to an external hot air part and an atomizing part; A cyclone separator, connected to the dryer body through the first air duct and led out through a second air duct, and a second flange ring is provided at the bottom of the cyclone separator; Two monitoring units are respectively arranged in the first air duct and the second air duct, and the monitoring units include an anemometer and two first electrode rings arranged in pairs, the first electrode rings are used to obtain induced electrical signals, and the two first electrode rings are used to calculate and obtain particle speed; Two barrel assemblies, the barrel assemblies comprising a barrel, a pressure sensor, an internal barometer and an external barometer, the two pressure sensors are respectively arranged on the first flange ring and the second flange ring, the two barrels are respectively mounted on the two pressure sensors and are movable in the vertical direction, the internal barometer and the external barometer respectively test the air pressure inside and outside the barrel; A controller controls the inner barometer, the outer barometer, the pressure sensor, the anemometer and the first electrode ring.

2. The spray dryer with particle state monitoring according to claim 1, characterized in that The bottom end of the dryer body is a detachable transition tube, the material barrel is installed on the transition tube, and a buffer pad is arranged at the connection position on the top of the transition tube.

3. The spray dryer with particle state monitoring according to claim 2, characterized in that A second electrode ring connected to and controlled by the controller is arranged on the inner wall of the transition cylinder.

4. The spray dryer with particle state monitoring according to claim 3, characterized in that An ultrasonic probe connected to and controlled by the controller is arranged on the top of the barrel or in the transition tube, the detection direction of the ultrasonic probe points to the bottom of the barrel, and a vibration motor connected to and controlled by the controller is arranged on the barrel.

5. The spray dryer with particle state monitoring according to any one of claims 1 to 4, characterized in that: The anemometers on the first air duct and the second air duct are both detachable.

6. The spray dryer with particle state monitoring according to any one of claims 1 to 4, characterized in that The pressure sensor is ring-shaped.

7. A control method, applied to the spray dryer with particle state monitoring according to claim 1, characterized in that: include: S1. Acquire first pressure sensing data of the pressure sensor on the dryer body in real time, and calculate and obtain first real-time gross weight of the material; S2, obtaining first air pressure sensor data of the internal barometer and the external barometer on the dryer body, and correcting the first real-time material gross weight to obtain a first real-time material weight; S3, obtaining first real-time sensing data of the two first flange rings on the first air duct, and calculating and obtaining a first real-time particle velocity; S4, obtaining a first real-time air flow velocity of the anemometer on the first air duct; S5. Obtain first real-time equivalent particle size data according to the first real-time particle velocity and the first real-time airflow velocity.

8. The control method according to claim 7, characterized in that: The step S5 then includes: S601, obtaining a set time interval, and calculating a first cumulative material weight and a first cumulative charge within the set time interval according to the first real-time material weight and the first real-time sensing data; S602, obtaining average equivalent particle size data according to the equivalent particle size data within the set time interval; S603, calculating the ratio between the first cumulative charge and the first cumulative material weight, and weightedly combining the average equivalent particle size data to evaluate the moisture content in the dry airflow.

9. The control method according to claim 7, characterized in that: The step S5 then includes: S701, acquiring in real time the second pressure sensing data of the pressure sensor on the cyclone separator, and calculating and obtaining the second real-time gross weight of the material; S702, obtaining second air pressure sensor data of the inner barometer and the outer barometer on the cyclone separator, and correcting the second real-time material gross weight to obtain a second real-time material weight; S703: Calculate the real-time material output according to the first real-time material weight and the second real-time material weight.

10. The control method according to claim 7, characterized in that: The top of the barrel is provided with an ultrasonic probe connected to and controlled by the controller, the detection direction of the ultrasonic probe points to the bottom of the barrel, and the barrel is provided with a vibration motor connected to and controlled by the controller, and the step S2 includes: S801, calculating the total weight of materials according to the first real-time material weight; S802, after controlling the vibration motor to work, acquiring the sensing data of the ultrasonic probe and calculating the material stacking height; S803: Evaluate the product status of the material in the material barrel on the dryer body according to the total weight of the material and the material stacking height.

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