Static classifier back powder online detection system coupling multi-flow control wind intelligent regulation and control method

Abstract

The application provides a static classifier back powder online detection system coupling multi-flow intelligent control method, a plurality of multi-flow adjustment connecting air pipes are arranged in communication with the air inlet side of the air inlet chamber of the static classifier in the system, the multi-flow adjustment connecting air pipes are located at the upper portion, the middle portion and the lower portion of the entire vertical section of the air inlet side, the system circulating air is completely utilized, the purpose of uniform air inlet is achieved while meeting the powder selection gas flow requirement of the static classifier. The back powder detection system is arranged between the back powder return bed of the static classifier and the grinding equipment, the back powder online detection is realized, and the material self-circulation is detected. In addition, under the control of the control system, the fine powder content in the back powder of the static classifier is automatically detected online, the dynamic balance of the multi-flow air control of the static classifier is adjusted in real time, the fine powder content in the back powder of the static classifier is regulated, and the grinding efficiency of the material bed grinding is improved. Compared with the traditional manual adjustment according to the intuitive feeling, the adjustment is more rapid, convenient and accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of detection control of grinding system, and more particularly to a static classifier back powder online detection system coupling multi-flow control air intelligent regulation method. BACKGROUND

[0002] The V-shaped static classifier is a kind of unpowered scattering and classifying equipment, which is widely used in the combined grinding system, semi-final grinding system, final grinding system and external circulation vertical grinding system of the roller press, and mainly functions to classify the coarse and fine particles of the material ground by the material bed grinding equipment, so that the coarse particles are returned to the material bed grinding equipment for regrinding, and the fine particles are used as semi-final products to enter the subsequent fine dynamic powder selecting equipment or directly collected into the ball mill for processing. If the back powder contains more fine particles, the grinding efficiency of the material bed grinding equipment will be affected, and if the semi-final products contain more coarse particles, the processing efficiency of the subsequent process will be affected.

[0003] The current V-shaped static classifier adopts a single air inlet type, mainly uses the circulating air introduced from the system circulating fan as the powder selecting gas flow, and the connection mode of the inlet air pipe and the V-shaped static classifier is different according to the situation of each site, which easily causes uneven air flow distribution into the V-shaped static classifier, affecting the classification efficiency.

[0004] According to the numerical simulation theory analysis, the V-shaped static classifier has the common problems of local high wind speed caused by wind short circuit at the top and uneven cross-sectional wind speed distribution, when the wind is drawn, a large number of coarse particles directly enter the fine dynamic powder selecting machine or ball mill, affecting the powder selecting or grinding efficiency of the subsequent process, and increasing the equipment resistance of the V-shaped static classifier itself; when the wind is drawn, the classification efficiency of the V-shaped static classifier is reduced, the content of fine powder in the back powder is increased, and more finished products are returned to the material bed grinding equipment, affecting the stability of the material bed and the grinding efficiency.

[0005] The content of fine powder in the back powder of the static classifier is a very key technical index for evaluating the equipment, and in actual operation, the back powder amount is large, and manual detection of the content of fine powder in the cross-sectional back powder amount of the entire equipment has the problems of long time consumption, laborious sampling, limited operation, representative sampling, low operation consistency and detection efficiency. SUMMARY

[0006] The present application provides a static classifier back powder online detection system, which is used to solve the problems of uneven air flow distribution of the V-shaped static classifier, increased content of fine powder in the back powder, and time-consuming and laborious operation of detecting the content of fine powder in the back powder in the prior art.

[0007] The application provides a static classifier back powder online detection system, which comprises a static classifier, a multi-flow adjusting connecting air pipe which is arranged in communication with an air inlet side of an air inlet chamber of the static classifier, the multi-flow adjusting connecting air pipe is in the same plane with the static classifier and is located at the upper part, the middle part and the lower part of the entire vertical section of the air inlet side, the multi-flow adjusting connecting air pipe comprises a multi-flow adjusting main air pipe located at the top and a plurality of multi-flow adjusting branch air pipes located below the multi-flow adjusting main air pipe, and the multi-flow adjusting main air pipe and the multi-flow adjusting branch air pipes are arranged side by side, the pipe diameter of the multi-flow adjusting main air pipe is larger than that of the multi-flow adjusting branch air pipes, and the multi-flow adjusting main air pipe is connected with a main air inlet of the air inlet chamber.

[0008] The static classifier back powder online detection system further comprises a control system for controlling the operation of all devices, a first metering device, a screening device and a second metering device which are sequentially connected with a back powder outlet of the static classifier, a fine powder outlet of the screening device is connected with the second metering device, the first metering device is used for weighing a first portion of material discharged from the back powder outlet to obtain first data and transmitting the first data to the control system, the screening device is used for screening the first portion of material into a first fine powder and a first coarse powder and discharging the first fine powder from the fine powder outlet of the screening device to the second metering device, the second metering device is used for weighing the first fine powder to obtain second data and transmitting the second data to the control system, and the control system is further used for calculating the fine powder content in the back powder of the static classifier according to the first data and the second data.

[0009] Optionally, the back powder outlet is connected with a first material distribution control valve.

[0010] A first pipeline of the first material distribution control valve is connected with the first metering device, and the first pipeline is used for discharging a first portion of material to the first metering device when back powder detection is needed.

[0011] A second pipeline of the first material distribution control valve is used for discharging back powder which is not subjected to back powder detection from the static classifier.

[0012] Optionally, the system further comprises a stable material weighing bin and a material bed grinding device, a feeding port of the stable material weighing bin is connected with the second pipeline of the first material distribution control valve and the coarse powder outlet of the screening device respectively, and the stable material weighing bin is used for collecting a second portion of material discharged from the second pipeline of the first material distribution control valve and the first coarse powder discharged from the coarse powder outlet of the screening device.

[0013] A discharging port of the stable material weighing bin is connected with the material bed grinding device, and the material bed grinding device is used for grinding the first coarse powder and the second portion of material.

[0014] Optionally, the system further comprises an elevator.

[0015] The elevator is connected with the discharge port of the material bed grinding device, the second metering device and the feeding port of the static classifier respectively, and is used for conveying the material into the static classifier for sorting.

[0016] Optionally, the elevator is further connected with the first feeding device.

[0017] Optionally, the second feeding device is further connected with the feeding pipeline of the material stabilizing and weighing bin.

[0018] Optionally, the on-line gas flow detection device and the collecting device are further arranged on the circulating air loop between the air outlet and the air inlet of the static classifier.

[0019] The air outlet is connected with the collecting device, the on-line gas flow detection device and a system circulating air fan for providing system circulating air in sequence; the air outlet of the system circulating air fan is connected with the air inlet; the collecting device is used for collecting the material from the air outlet into the collecting device; the on-line gas flow detection device is used for detecting the gas flow discharged from the collecting device to obtain third data, and transmitting the third data to the control system.

[0020] Optionally, the fine dynamic powder classifier and the second material distribution control valve are further included.

[0021] The inlet of the fine dynamic powder classifier is connected with the air outlet; the fine powder outlet of the fine dynamic powder classifier is connected with the inlet of the collecting device; and the fine dynamic powder classifier is used for performing secondary sorting on the material discharged from the static classifier.

[0022] The coarse powder outlet of the fine dynamic powder classifier is connected with the lower part of the air outlet side of the static classifier.

[0023] Optionally, the first single-pass control valve and the second single-pass control valve are further included and electrically connected with the control system; and the control system is used for controlling the opening and closing of the first single-pass control valve and the second single-pass control valve.

[0024] The first single-pass control valve is arranged between the first metering device and the screening device, and is used for controlling whether the material in the first metering device can enter the screening device.

[0025] The second single-pass control valve is arranged between the second metering device and the elevator, and is used for controlling whether the material in the second metering device can enter the elevator.

[0026] Optionally, the control valve is arranged on the multi-flow regulation main air pipe and the multi-flow regulation branch air pipe respectively, each control valve is used for controlling the gas flow and the air speed in the corresponding air pipe, and each control valve is electrically connected with the control system.

[0027] Optionally, an angle range of the included angle θ6 between the air inlet direction of the multi-flow regulation connecting air pipe and the horizontal plane is 35-55°.

[0028] An angle range of the included angle θ5 between the air outlet direction of the multi-flow regulation connecting air pipe and the horizontal plane is 20-35°.

[0029] An angle range of the included angle θ4 between the air inlet side shell of the air inlet chamber and the horizontal plane is 50-75°.

[0030] Optionally, a design air volume of the multi-flow regulation main air pipe accounts for 50-70% of the total air volume, and a design air speed V1 of the multi-flow regulation main air pipe ranges from 12 to 16 m / s.

[0031] A design air speed Vpi of the multi-flow regulation branch air pipe ranges from 9 to 14 m / s.

[0032] The application further provides a static classifier back powder coupling multi-flow control air intelligent regulation method, which is applied to the static classifier back powder online detection system and comprises the following steps.

[0033] Step 1, a first material is discharged from the first metering device into the material discharged from the static classifier back powder outlet by controlling the first material control valve, and first data T1 measured by the first metering device is acquired.

[0034] Step 2, the first material is screened into first coarse powder and first fine powder in the screening device by opening the first single-way control valve, and the first fine powder obtained after screening is introduced into the second metering device.

[0035] Step 3, second data T2 of the first fine powder measured by the second metering device is acquired, and the fine powder content P in the static classifier back powder is calculated according to the ratio of the second data T2 to the first data T1.

[0036] Step 4, the size relation between the fine powder content P in the back powder and a preset fine powder content P0 in the back powder is judged.

[0037] When P≤P0, the multi-flow regulation connecting air pipe control valve is not adjusted.

[0038] When P>P0, the regulation process is as follows.

[0039] Step 401, third data f1 detected by the online gas flow detection device is acquired.

[0040] Step 402, sequentially increase the valve opening of all multi-flow adjustment branch air pipes by a proportion one, and decrease the valve opening of the multi-flow adjustment main air pipe by a proportion two;

[0041] Step 403, acquire the fourth data f2 detected by the online gas flow detection device again, and calculate the absolute value of the difference between the fourth data f2 and the third data f1; the fourth data f2 is the gas flow data of the gas discharged from the collecting device after the multi-flow adjustment connection air pipe is adjusted;

[0042] determine whether the absolute value of the difference between the fourth data f2 and the third data f1 is within the preset error range; if it is determined that the absolute value of the difference between the fourth data f2 and the third data f1 is not within the preset error range, repeat steps 402-404 until it is determined that the difference between the fourth data f2 and the third data f1 is within the preset error range;

[0043] Step 5, repeat steps 1-4 until it is determined that the fine powder content P is less than or equal to the fine powder content P0, and then complete one adjustment.

[0044] Optionally, the application further comprises:

[0045] In step 2, the first coarse powder obtained after screening enters the stable material weighing bin.

[0046] In step 3, after acquiring the second data T2 of the first fine powder measured by the second metering device, open the second single-pass control valve, so that the first fine powder in the second metering device enters the elevator.

[0047] Optionally,

[0048] The proportion one ranges from 1% to 15%.

[0049] The proportion two ranges from 1% to 10%.

[0050] The application has at least the following beneficial effects:

[0051] The application provides a static classifier back powder online detection system and an intelligent regulation and control method, a plurality of flow regulation connection air pipes are arranged on the same horizontal plane of the air inlet end face of the air inlet chamber of the static classifier in the system. The plurality of flow regulation connection air pipes are located on the same plane as the static classifier and are located on the upper part, the middle part and the lower part of the entire vertical section of the air inlet side, the plurality of flow regulation connection air pipes comprise a plurality of flow regulation main air pipes located at the top and a plurality of flow regulation branch air pipes located below the plurality of flow regulation main air pipes. In the case of meeting the requirements of the static classifier powder selection gas flow, the purpose of uniform air inlet is achieved, and the classification efficiency is improved. The airflow in the height direction of the static classifier is more uniform, the classification efficiency is improved, the equipment resistance is reduced, the system circulating air is fully utilized, the pressure balance of the entire system is maintained, and the energy consumption of the system fan is reduced. In addition, the fine powder content in the back powder of the static classifier is automatically detected online by controlling the detection system through the control system, the dynamic balance of the multi-flow air control of the static classifier is adjusted in real time, the fine powder content in the back powder of the static classifier is regulated and controlled, and the grinding efficiency of the material bed grinding is improved. Compared with the traditional manual adjustment according to the intuitive feeling of the system, the adjustment is more rapid, convenient and accurate. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0053] Figure 1 It is a schematic diagram of the static classifier back powder online detection system provided by the application;

[0054] Figure 2 It is a three-dimensional schematic diagram of the static classifier structure of the application;

[0055] Figure 3 It is a planar schematic diagram of the static classifier of the application.

[0056] 1, total air inlet pipe; 2, multi-flow adjustment main air pipe; 3, feeding port; 4, air outlet; 5, shell; 6, grading plate; 7, powder outlet; 8, guide plate; 9, multi-flow adjustment branch air pipe; 10, multi-flow adjustment main air pipe valve; 11, multi-flow adjustment branch air pipe valve; 12, static classifier; 13, first material distribution control valve; 14, first metering device; 15, first single-pass control valve; 16, screening device; 17, second metering device; 18, second single-pass control valve; 19, material stabilizing weighing bin; 20, material bed grinding equipment; 21, first feeding equipment; 22, second feeding equipment; 23, elevator; 24, fine dynamic powder classifier; 25, second material distribution control valve; 26, collecting device; 27, online gas flow detection device; 28, system circulating fan; 29, air release pipe; 30, system circulating air pipe. DETAILED DESCRIPTION

[0057] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0058] The present application provides a static classifier 12 powder return online detection system, the air inlet side of the air inlet chamber of the static classifier 12 is communicated with a multi-flow adjustment connecting air pipe, the multi-flow adjustment connecting air pipe is in the same plane with the static classifier and is located in the upper, middle and lower parts of the entire vertical section of the air inlet side; the multi-flow adjustment connecting air pipe includes a multi-flow adjustment main air pipe 2 located at the top and a plurality of multi-flow adjustment branch air pipes 9 located below the multi-flow adjustment main air pipe, and the multi-flow adjustment main air pipe 2 and the multi-flow adjustment branch air pipes 9 are arranged side by side; the pipe diameter of the multi-flow adjustment main air pipe 2 is greater than that of the multi-flow adjustment branch air pipes 9, and the multi-flow adjustment main air pipe 2 is connected with the main air inlet of the air inlet chamber;

[0059] The static classifier back powder online detection system further comprises a control system for controlling the operation of all devices, and a first metering device 14, a screening device 16 and a second metering device 17 connected in turn with the back powder outlet of the static classifier 12; the fine powder outlet of the screening device 16 is connected with the second metering device 17; the first metering device 14 is used for weighing the first portion of material discharged from the back powder outlet to obtain first data, and transmitting the first data to the control system; the screening device 16 is used for screening the first portion of material into first fine powder and first coarse powder, and discharging the first fine powder from the fine powder outlet of the screening device 16 to the second metering device 17; the second metering device 17 is used for weighing the first fine powder to obtain second data, and transmitting the second data to the control system, and the control system is further used for calculating the fine powder content in the back powder of the static classifier according to the first data and the second data.

[0060] Specifically, the internal space of the static classifier 12 housing 5 includes an air inlet chamber and an air outlet chamber, which form a V-shaped structure. A plurality of stepwise inclined guide plates 8 are arranged in the air inlet chamber, and a plurality of stepwise inclined classification plates 6 are arranged in the air outlet chamber. An air outlet 4 for discharging fine powder is arranged at the top of the air outlet chamber. A back powder outlet 7 for discharging coarse powder is arranged at the bottom of the housing 5, and a feeding port 3 is arranged at the top of the housing 5 between the air inlet chamber and the air outlet chamber.

[0061] From the three-dimensional schematic diagram of the static classifier and the planar schematic diagram of the static classifier, it can be seen that the static classifier 12 in the static classifier back powder online detection system is located at the top of the intersection of the V-shaped structure formed by the air inlet chamber and the air outlet chamber, and the material is fed into the static classifier 12 from the feeding port 3. After the material enters the air inlet chamber, it is dispersed under the action of the airflow. A plurality of stepwise inclined guide plates 8 are arranged in the air inlet chamber, which help the material to be uniformly distributed and preliminarily classified in the air inlet chamber. The material enters the air outlet chamber along with the airflow, and a plurality of stepwise inclined classification plates 6 are arranged in the air outlet chamber, which further classify the material according to the size and weight of the particles. Larger material particles will slide down along the classification plates 6 due to their larger weight and size, and finally be discharged through the back powder outlet at the bottom. Smaller material particles are discharged through the gap between the classification plates 6 and the fine powder outlet, and the required fine powder is collected.

[0062] The multi-flow regulation connection air inlet is connected with a total air inlet pipe 1, which can take air from the top or the bottom and is not affected by the process system layout. The multi-flow regulation connection air pipe includes a multi-flow regulation main air pipe 2 with a large pipe diameter and a plurality of multi-flow regulation branch air pipes 9 with small pipe diameters, which are arranged in an inverted V-shaped structure. The multi-flow regulation connection air pipe is in the same plane as the static classifier 12 and is located in the upper, middle and lower parts of the entire vertical section of the air inlet side to achieve uniform distribution and regulation of the airflow. The pipe diameter of the multi-flow regulation main air pipe 2 is larger than that of the multi-flow regulation branch air pipes 9. The multi-flow regulation main air pipe 2 serves as the main air inlet channel of the air inlet chamber and needs to ensure sufficient airflow strength to drive the movement and dispersion of the material in the static classifier 12. The larger pipe diameter can reduce the resistance of the airflow during transmission and ensure that the main airflow can smoothly and efficiently enter the air inlet chamber.

[0063] The first metering device 14 weighs the material discharged from the back powder outlet 7 at the bottom of the static classifier 12, i.e., the first portion of material. After the first portion of material is weighed, the weight of the first portion of material is obtained as the first data, and the first data is transmitted to the control system for storage. The weighed first portion of material is sieved by the sieving device 16 to obtain first coarse powder and first fine powder. The second metering device 17 weighs the first fine powder to obtain the second data, and the second data is transmitted to the control system. The control system calculates the fine powder content in the back powder according to the first data and the second data. The first metering device 14, the sieving device 16 and the second metering device 17 are electrically connected with the control system, and the control system controls and coordinates each device in the back powder online detection system of the static classifier 12.

[0064] In a possible implementation, the back powder outlet is connected with a first material distribution control valve 13.

[0065] The first pipeline of the first material distribution control valve 13 is connected with the first metering device, and the first pipeline is used to discharge the first portion of material to the first metering device 14 when back powder detection is needed.

[0066] The second pipeline of the first material distribution control valve 13 is used to discharge the back powder in the static classifier 12 that does not need to be detected.

[0067] Specifically, the first material distribution control valve 13 is also electrically connected with the control system. The back powder outlet 7 at the bottom of the static classifier 12 is connected with the first material distribution control valve 13. A certain amount of coarse material obtained after classification is taken as the first portion of material and is shunted to the first metering device 14 through the first pipeline of the first material distribution control valve 13 for weighing. The remaining material is shunted to other processes through the second pipeline of the first material distribution control valve 13.

[0068] In a possible implementation, the system further comprises a material stabilizing and weighing bin 19 and a material bed grinding device 20; the material stabilizing and weighing bin 19 is connected with the second pipeline of the first material distribution control valve 13 and the coarse powder outlet of the screening device 16 respectively, and the material stabilizing and weighing bin 19 is used to collect the second portion of material discharged from the second pipeline of the first material distribution control valve 13 and the first coarse powder discharged from the coarse powder outlet of the screening device 16.

[0069] The material stabilizing and weighing bin 19 is connected with the material bed grinding device 20, and the material bed grinding device 20 is used to grind the first coarse powder and the second portion of material.

[0070] Specifically, most of the returned powder after the classification of the static classifier 12 is transported to the material stabilizing and weighing bin 19 through the second pipeline of the first material distribution control valve 13, and the first coarse powder after the screening of the screening device 16 also enters the material stabilizing and weighing bin 19, and then the material in the material stabilizing and weighing bin 19 enters the material bed grinding device 20 for grinding. The material stabilizing and weighing bin 19 is also used to buffer the material, which can help to stabilize the material supply and prevent the fluctuation of the grinding system caused by unstable material supply. Moreover, the material can be supplied in a stable and continuous manner before entering the material bed grinding device 20, which can ensure the normal operation of the material bed grinding device 20 and improve the grinding efficiency.

[0071] In a possible implementation, the system further comprises an elevator 23.

[0072] The elevator 23 is connected with the discharge outlet of the material bed grinding device 20, the second metering device 17 and the feeding inlet 3 of the static classifier 12 respectively, and the elevator 23 is used to transport the material entering the elevator 23 to the static classifier 12 for primary separation.

[0073] Specifically, the material after the grinding of the material bed grinding device 20 enters the elevator 23, and the first fine powder after the weighing of the second metering device 17 also enters the elevator. The elevator 23 lifts the amount of the first fine powder and the amount of the second portion of material together to the feeding inlet 3 of the static classifier 12 and feeds them into the static classifier 12 for primary separation.

[0074] In a possible implementation, the elevator is further connected with the first feeding device 21.

[0075] Specifically, the first feeding device 21 is connected with the elevator, in which case the material in the first feeding device 21 does not need to be ground and can be directly sent into the static classifier 12 through the elevator. In this case, the feeding device is the first feeding device 21, which is directly connected with the elevator 23, and the elevator 23 sends the amount of material fed by the feeding device into the classifier for separation.

[0076] In a possible implementation, a second feeding device 22 is further included, which is connected with the feeding pipe of the steady material weighing bin 19.

[0077] Specifically, if the material needs to be ground before being sorted, the second feeding device 22 is connected with the feeding pipe of the steady material weighing bin 19, and the material enters the steady material weighing bin from the second feeding device 22 and is then sent into the material bed grinding device 20 for grinding.

[0078] In a possible implementation, an online gas flow detection device 27 and a collection device 26 are further included on the circulating air loop between the air outlet 4 and the air inlet of the static classifier 12.

[0079] The air outlet 4 is connected with the collection device 26, the online gas flow detection device 27 and a system circulating air fan 28 for providing system circulating air in sequence; the air outlet of the system circulating air fan 28 is connected with the air inlet; the collection device 26 is used for collecting the material entering the collection device 26 from the air outlet 4, the online gas flow detection device 27 is used for detecting the gas flow discharged from the collection device 26 to obtain third data, and the third data is transmitted to the control system.

[0080] Specifically, the circulating air of the static classifier 12 in the application is provided by the system circulating air fan 28. The gas discharged from the air outlet of the system circulating air fan 28 is partially discharged into the next process through the air release pipe 29, and the other part of the gas is introduced into the system circulating air pipe 30. A total air inlet pipe 1 is connected with the system circulating air pipe 30, and the total air inlet pipe is in communication with the air inlet end surface of the air inlet chamber. The system circulating air pipe 30 is not directly connected with the static classification device, and the air inlet of the static classifier 12 is no longer affected by different arrangement types of the system circulating air pipe, and the total air inlet pipe 1 plays a role of mixing and buffering the air flow, so that the air flow entering the static classifier 12 in the width direction is more uniform. The gas containing fine powder extracted from the static classifier 12 by the system circulating air fan 28 is collected, and the discharged air is introduced into the total air inlet pipe 1 again by the circulating air fan to realize air circulation. The air entering the total air inlet pipe 1 enters the multi-flow adjustment main air pipe 2 and the multi-flow adjustment branch air pipe 9 in sequence, and the outlets of the multi-flow adjustment main air pipe 2 and the multi-flow adjustment branch air pipe 9 enter the housing 5 to classify the material fed from the feeding port 3. The total air inlet pipe 1 is connected with the system circulating air pipe 30, has the functions of upper air inlet and / or lower air inlet, and the air outlet of the system circulating air fan 28 is connected with the air inlet having the functions of upper air inlet and / or lower air inlet.

[0081] The fine powder carried by the primary separation, discharged from the outlet 4 of the static classifier 12, is collected by the collecting device 26. The fine powder collected by the collecting device 26 is used for the next process. If the fine powder after primary separation cannot meet the average particle size of the finished product, the next process is generally re-grinding. The gas discharged after the primary separation of fine powder is collected is discharged from the collecting device 26. An online gas flow detection device 27 is connected to the gas outlet of the collecting device 26. The online gas flow detection device 27 detects the gas flow rate discharged from the collecting device 26, obtains third data, and transmits the third data to the control system for storage.

[0082] In one possible implementation, it also includes a fine dynamic classifier 24 and a second material distribution control valve 25;

[0083] The inlet of the fine dynamic classifier 24 is connected to the air outlet 4, and the fine powder outlet of the fine dynamic classifier 24 is connected to the inlet of the collection device 26; the fine dynamic classifier 24 is used to perform secondary sorting on the material discharged from the static classifier 12.

[0084] The coarse powder outlet of the fine dynamic classifier 24 is connected to the lower part of the air outlet side of the static classifier 12.

[0085] Specifically, a fine dynamic classifier 24 can be installed between the air outlet 4 of the static classifier 12 and the feed inlet of the collecting device 26 to perform secondary classification on the fine powder after primary classification, obtaining fine powder with particle size meeting the process requirements. The coarse powder obtained from the secondary classification by the fine dynamic classifier 24 is returned to the static classifier 12 or enters the next process according to the process requirements through the second material distribution control valve 25. The next process is generally re-grinding.

[0086] In one possible implementation, a first one-way control valve 15 and a second one-way control valve 18 electrically connected to the control system are also included; the control system is used to control the opening and closing of the first one-way control valve 15 and the second one-way control valve 18.

[0087] The first single-pass control valve 15 is disposed between the first metering device 14 and the screening device 16. The first single-pass control valve 15 is used to control whether the material in the first metering device 14 can enter the screening device 16.

[0088] The second single-way control valve 18 is disposed between the second metering device 17 and the elevator 23. The second single-way control valve 18 is used to control whether the material in the second metering device 17 can enter the elevator 23.

[0089] Specifically, a first one-way control valve 15 is provided between the first metering device 14 and the screening device 16. When the first one-way control valve 15 is open, the material in the first metering device 14 can enter the screening device 16; when the first one-way control valve 15 is closed, the material in the first metering device 14 cannot enter the screening device 16. Similarly, a second one-way control valve 18 is provided between the second metering device 17 and the elevator 23. When the second one-way control valve 18 is open, the material in the second metering device 17 can enter the elevator 23; when the second one-way control valve 18 is closed, the material in the second metering device 17 cannot enter the elevator 23.

[0090] In one possible implementation, control valves are respectively installed on the multi-flow regulating main air duct 2 and the multi-flow regulating branch air duct 9. Each control valve is used to control the gas flow rate and wind speed in the corresponding air duct, and each control valve is electrically connected to the control system.

[0091] Specifically, a multi-flow regulating main air duct 2 is equipped with a multi-flow regulating main air duct valve 10 to regulate the gas flow rate and air velocity within the multi-flow regulating main air duct 2. Each multi-flow regulating branch air duct is equipped with a corresponding multi-flow regulating branch air duct valve 11 to regulate the gas flow rate and air velocity within the corresponding multi-flow regulating branch air duct 9.

[0092] In one possible implementation, the angle θ6 between the air inlet direction of the multi-flow regulating connecting duct and the horizontal plane is in the range of 35° to 55°.

[0093] The angle θ5 between the air outlet direction of the multi-flow regulating connecting air duct and the horizontal plane is in the range of 20 to 35°.

[0094] The angle θ4 between the air inlet side shell of the air inlet chamber and the horizontal plane ranges from 50° to 75°.

[0095] Specifically, a suitable angle range helps reduce energy loss during airflow transmission and improve system efficiency. Setting the angle θ6 within the range of 35–55° allows the inlet duct to receive airflow from the main inlet duct 1 at a suitable angle, reducing resistance. The acute angle θ4 between the inlet end face of the inlet chamber and the horizontal plane ranges from 50–75°, allowing the material to achieve a more uniform suspension state within the inlet chamber, which is beneficial for improving material grading effect and accuracy, and helps to ensure smooth airflow discharge.

[0096] In one possible implementation, the design air volume of the multi-flow regulating main air duct accounts for 50-70% of the total air intake volume, and the design air velocity V1 of the multi-flow regulating main air duct is in the range of 12-16 m / s.

[0097] The design wind speed Vpi range of the multi-flow regulating air distribution duct 9 is 9 to 14 m / s.

[0098] Specifically, the design gas flow rate of the multi-flow regulating main duct 2 accounts for 50-70% of the total inlet gas flow rate. This means that the system can effectively distribute most of the airflow into the multi-flow regulating main duct 2, and then distribute it to each air inlet chamber through the multi-flow regulating main duct 9, ensuring reasonable airflow distribution and avoiding excessively high or low gas flow rates in certain areas. If the design gas flow rate of the multi-flow regulating main duct 2 exceeds this range, the gas flow rate in other multi-flow regulating main ducts 9 will be too low, failing to achieve uniform airflow and resulting in poorer sorting performance.

[0099] In this application, the straight line S2 where the endpoints of the multiple guide plates 8 are near the air outlet chamber is parallel to the straight line S1 where the endpoints of the multiple classifying plates 6 are near the air inlet chamber. The channel between the straight lines S1 and S2 is a material channel; the feeding port 3 is located upstream of the top opening of the material channel and is offset, and the powder return outlet is located downstream of the bottom opening of the material channel and is offset.

[0100] The inlet pipe and outlet pipe of the multi-flow regulating connecting duct are connected by a bend, and the outlet of the bend is the inlet of the outlet pipe of the multi-flow regulating connecting duct.

[0101] In this application, the design of the guide plate 8 and the classifying plate 6 creates a clear material channel within the static classifier 12, facilitating the orderly flow and separation of materials during the classification process. Furthermore, the staggered feeding port 3 at the top of the material channel is primarily to prevent newly added material from directly entering the critical classification area of ​​the static classifier 12 from the top opening, which could potentially affect the classification effect of materials already in the classification process. By staggering the feeding port 3 from the channel inlet, newly added material first falls into a buffer area and then gradually enters the classification area, thereby reducing direct interference. The staggered return outlet at the bottom of the material channel is designed to prevent coarse particles from flowing directly out of the bottom opening and being discharged directly from the return powder outlet 7, causing insufficiently classified material to be prematurely removed from the static classifier 12 and reducing classification efficiency. Through this staggered arrangement, coarse particles are first carried to a higher position under the influence of gravity and airflow, and then gradually fall to the return outlet, thus increasing the opportunity and time for classification.

[0102] The inlet and outlet ducts of the multi-flow regulating connecting duct are connected by a bend, which reduces turbulence and vortices in the airflow during transmission. These turbulence and vortices not only increase energy loss but can also affect the uniform distribution of airflow. Furthermore, the smooth transition design of the bend reduces changes in airflow velocity and the degree of turbulence, thereby ensuring uniform airflow distribution.

[0103] In this application, the material concentration per unit volume of the material channel between the guide plate 8 and the grading plate 6 is in the range of 100–150 t / h·m³. 3 The feed concentration per unit area at feed inlet 3 ranges from 1000 to 1400 t / h·m 2 A clearly defined material concentration range ensures the efficient operation of the static classifier 12. Controlling the material concentration per unit volume in the material channel within a certain range avoids blockages caused by excessively high concentrations or poor classification results due to excessively low concentrations.

[0104] This invention also provides a method for intelligent control of powder return coupled with multi-flow airflow in a static classifier, applied to the online powder return detection system of the static classifier in this invention, comprising the following steps:

[0105] Step 1: Control the first material distribution control valve 13 to discharge the first portion of material discharged from the powder return outlet 7 of the static classifier 12 into the first metering device 14, and obtain the first data T1 measured by the first metering device 14.

[0106] Specifically, the first single-pass control valve 15 is controlled to be closed, then the first pipeline of the first dispensing control valve 13 is opened, and a certain amount of graded return powder discharged from the return powder outlet 7 of the static classifier 12 enters the first metering device 14. Then, the first pipeline is closed. This certain amount of return powder constitutes the first batch of material. After the weight data measured in the first metering device 14 stabilizes, the stabilized weight data is transmitted as the first data to the control system for storage.

[0107] Step 2: Open the first single-pass control valve 15 to allow the first portion of material to enter the screening device 16 from the first metering device 14 and be screened into the first coarse powder and the first fine powder, and allow the first fine powder obtained after screening to enter the second metering device 17.

[0108] Specifically, the first single-pass control valve 15 is opened, allowing the first portion of material in the first metering device 14 to enter the screening device 16 for screening. After being screened by the screening device 16, the first portion of material yields a first fine powder with smaller particles and a first coarse powder with larger particles. The first fine powder enters the second metering device 17 from the fine powder outlet of the screening device 16.

[0109] Step 3: Obtain the second data T2 of the first fine powder measured by the second metering device 17; the second data T2 is the weight data of the first fine powder, and calculate the fine powder content P in the powder returned by the static classifier 12 according to the ratio of the second data T2 to the first data T1.

[0110] Specifically, when the screening device 16 is detected to be unloaded, it is determined that the first batch of material entering the screening device 16 has been completely screened and the first fine powder obtained from screening has entered the second metering device 17. At this time, the control system calculates the specific value of the fine powder content P in the returned powder according to the preset calculation method, namely: P = (T2 / T1) × 100.

[0111] Step 4: Determine the relationship between the fine powder content P in the recycled powder and the preset fine powder content P0 in the recycled powder;

[0112] When P≤P0, the control valve of the multi-flow regulating connection duct does not need to be adjusted;

[0113] When P > P0, the regulation process is as follows:

[0114] Step 401: Obtain the third data f1 detected by the online gas flow detection device 27;

[0115] Step 402: Increase the valve opening of all multi-flow regulating branch pipes 9 in proportion one from bottom to top, and decrease the valve opening of the multi-flow regulating main pipe 2 in proportion two.

[0116] Step 403: Obtain the fourth data f2 detected by the online gas flow detection device 27 again, and calculate the absolute value of the difference between the fourth data f2 and the third data f1; the fourth data f2 is the gas flow data discharged from the collection device 26 after the multi-flow regulating connecting duct is regulated;

[0117] Step 404: Determine whether the absolute value of the difference between the fourth data f2 and the third data f1 is within the preset error range; if it is determined that the difference between the fourth data f2 and the third data f1 is not within the preset error range, repeat steps 402 to 404 until it is determined that the absolute value of the difference between the fourth data f2 and the third data f1 is within the preset error range.

[0118] Step 5: Repeat steps 1 to 4 until the fine powder content P is determined to be less than or equal to the fine powder content P0, thus completing one adjustment.

[0119] Specifically, after the control system calculates the fine powder content P, it compares P with the preset fine powder content P0 set in the system. If the fine powder content P is greater than the preset fine powder content, it indicates that the current grading effect of the static classifier 12 is poor and the air velocity inside the static classifier 12 is uneven, requiring adjustment of the duct connecting the multi-flow regulating duct.

[0120] Step 401: The total gas flow rate is pre-set based on the material processing volume and the material-to-gas ratio, and is the total gas flow rate Q required for classification. The material-to-gas ratio is the ratio of the amount of material passing through the static classifier 12 per unit time to the amount of air. The total gas flow rate Q required for classification is the total gas flow rate at the outlet 4 of the static classifier 12 in its initial state. Before adjustment, the total gas flow rate discharged from the collection device 26 is detected by the online gas flow detection device 27, which is the third data f1.

[0121] Step 402: After obtaining the third data f1, adjust the multi-flow regulating connecting ducts. Each adjustment includes: sequentially increasing the valve opening of multiple multi-flow regulating branch ducts 9 from bottom to top, with the valve opening of each multi-flow regulating branch duct 9 increasing by a ratio of one, until all valves of the multi-flow regulating branch ducts 9 are adjusted. Then adjust the valve opening of the multi-flow regulating main duct 2, decreasing the valve opening of the multi-flow regulating main duct 2 by a ratio of two.

[0122] Step 403: After the multi-flow regulating connecting duct is adjusted once, the fourth data f2 detected by the line gas flow detection device is acquired again, and the absolute value of the difference between the fourth data f2 and the third data f1 is calculated; the fourth data f2 is the gas flow data discharged from the collection device 26 after the multi-flow regulating connecting duct is adjusted.

[0123] Step 404: After adjusting all the multi-flow regulating connecting ducts once, determine whether the absolute value of the difference between the fourth data f2 and the third data f1 is within the preset error range stored in the control system. If the difference between the fourth data f2 and the third data f1 is not within the preset error range, it means that the adjusted total gas flow rate is too far from the previously set initial total gas flow rate, and the multi-flow regulating connecting ducts need to be readjusted. Therefore, repeat steps 402 to 404 until the absolute value of the difference between the adjusted total gas flow rate and the fourth data f2 and the initial total gas flow rate f1 (i.e., the third data) is within the preset error range.

[0124] Step 5: After adjusting the multi-flow regulating duct, if the total air volume does not change significantly, repeat steps 1 to 4, re-detect the fine powder content P, and when the fine powder content P is less than or equal to the preset fine powder content P0, determine that one adjustment has been completed, and maintain the current state of the system for continuous operation.

[0125] It should be noted that after each adjustment is completed, starting from the moment the adjustment is determined to be completed, after a preset time t, steps 1 to 5 are executed again to detect the fine powder content in the returned powder. If the fine powder content does not meet the standard, adjustments are made until the fine powder content meets the standard, ensuring the efficient operation of the entire system.

[0126] In one possible implementation, it also includes:

[0127] In step 2, the first coarse powder obtained after screening is put into the material stabilization weighing bin 19;

[0128] In step 3, after obtaining the second data T2 of the first fine powder measured by the second metering device 17, the second single-pass control valve 18 is opened to allow the first fine powder in the second metering device 17 to enter the elevator 23.

[0129] In one possible implementation, the first proportion ranges from 1% to 15%; the second proportion ranges from 1% to 10%.

[0130] Specifically, setting the valve opening ratio for each multi-flow regulating duct to be adjusted once within a certain range can reduce system fluctuations caused by frequent or large-scale valve adjustments, thereby improving system stability.

[0131] In this application, the control system includes a detection start control unit, a data acquisition and calculation unit, a detection result judgment unit, a multi-flow control dynamic balance control unit, and a variable control standard judgment unit. The detection start control unit initiates the static classifier return powder detection process. The data acquisition and calculation unit acquires the data detected by the first metering device 14 and the second metering device 17 and calculates the fine powder content in the return powder. Then, the detection result judgment unit judges the detection result. If the expected standard is met, the system remains unchanged. If the expected standard is not met, the multi-flow control dynamic balance control unit adjusts the multi-flow regulating connection pipe for multi-channel airflow. After adjustment, the variable control standard judgment unit compares the current parameters with the expected variable control standard. If the variable control standard is met, the adjustment stops. If the variable control standard is not met, the multi-flow control dynamic balance adjustment is performed again until the variable control standard is met.

[0132] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0133] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An online detection system for recycled powder from a static classifier, comprising a static classifier, characterized in that: A multi-flow regulating connecting duct is connected to the air inlet side of the static classifier's air inlet chamber. The multi-flow regulating connecting duct is on the same plane as the static classifier and is located at the upper, middle, and lower parts of the entire vertical section on the air inlet side. The multi-flow regulating connecting duct includes a main multi-flow regulating duct at the top and multiple branch multi-flow regulating ducts below the main multi-flow regulating duct. The main multi-flow regulating duct and the branch multi-flow regulating ducts are arranged side by side. The diameter of the main multi-flow regulating duct is larger than the diameter of the branch multi-flow regulating ducts, and the main multi-flow regulating duct is connected to the main air inlet of the air inlet chamber. The static classifier return powder online detection system also includes a control system for controlling the operation of all equipment and a first metering device, a screening device, and a second metering device connected in sequence to the return powder outlet of the static classifier; the fine powder outlet of the screening device is connected to the second metering device; the first metering device is used to weigh the first part of material discharged from the return powder outlet to obtain first data, and transmit the first data to the control system; The screening device is used to screen the first part of the material into a first fine powder and a first coarse powder, and discharge the first fine powder from the fine powder outlet of the screening device to the second metering device; the second metering device is used to weigh the first fine powder to obtain second data, and transmit the second data to the control system; the control system is also used to calculate the fine powder content in the powder returned from the static classifier based on the first data and the second data.

2. The static classifier online powder return detection system according to claim 1, characterized in that, The powder return outlet is connected to a first material distribution control valve; The first pipeline of the first material dispensing control valve is connected to the first metering device. The first pipeline is used to discharge the first portion of material into the first metering device when it is necessary to perform powder return detection. The second pipeline of the first material distribution control valve is used to discharge the returned powder that is not detected in the static classifier.

3. The static classifier online powder return detection system according to claim 2, characterized in that, It also includes a material stabilizing weighing silo and a material bed grinding equipment; the inlet of the material stabilizing weighing silo is connected to the second pipeline of the first material distribution control valve and the screening device respectively; the material stabilizing weighing silo is used to collect the second part of material discharged from the second pipeline of the first material distribution control valve and the first coarse powder discharged from the coarse powder outlet of the screening device. The discharge port of the material stabilizing weighing bin is connected to the material bed grinding equipment, which is used to grind the first coarse powder and the second part of the material.

4. The static classifier online powder return detection system according to claim 3, characterized in that, It also includes hoists; The elevator is connected to the discharge port of the material bed grinding equipment, the second metering device, and the feeding port of the static classifier, respectively. The elevator is used to transport the material entering the elevator to the static classifier for sorting.

5. The static classifier online powder return detection system according to claim 4, characterized in that, The elevator is also connected to the first feeding device.

6. The static classifier online powder return detection system according to claim 4, characterized in that, It also includes a second feeding device, which is connected to the feed pipe of the material stabilizing weighing bin.

7. The static classifier online powder return detection system according to claim 4, characterized in that, It also includes an online gas flow detection device and a collection device located in the circulating air loop between the air outlet and the air inlet of the static classifier; The air outlet is sequentially connected to the collection device, the online gas flow detection device, and the system circulating fan for providing system circulating air; The system's circulating fan has its outlet and inlet connected; the collection device is used to collect materials entering the collection device from the outlet; the online gas flow detection device is used to detect the gas flow rate discharged from the collection device to obtain third data, and transmit the third data to the control system.

8. The static classifier online powder return detection system according to claim 7, characterized in that, It also includes a fine dynamic air classifier and a second material distribution control valve; The inlet of the fine dynamic classifier is connected to the air outlet, and the fine powder outlet of the fine dynamic classifier is connected to the inlet of the collection device; the fine dynamic classifier is used to perform secondary sorting on the material discharged from the static classifier. The coarse powder outlet of the fine dynamic air classifier is connected to the lower air outlet side of the static classifier.

9. The static classifier online powder return detection system according to claim 4, characterized in that, It also includes a first single-way control valve and a second single-way control valve that are electrically connected to the control system; the control system is used to control the opening and closing of the first single-way control valve and the second single-way control valve. The first single-pass control valve is located between the first metering device and the screening device, and is used to control whether the material in the first metering device can enter the screening device. The second single-way control valve is located between the second metering device and the elevator, and is used to control whether the material in the second metering device can enter the elevator.

10. The static classifier online powder return detection system according to claim 1, characterized in that, Control valves are installed on the multi-flow regulating main air duct and the multi-flow regulating branch air duct, respectively. Each control valve is used to control the gas flow rate and wind speed in the corresponding air duct, and each control valve is electrically connected to the control system.

11. The static classifier online powder return detection system according to claim 10, characterized in that, The angle θ6 between the air inlet direction of the multi-flow regulating connecting duct and the horizontal plane is in the range of 35° to 55°. The angle θ5 between the air outlet direction of the multi-flow regulating connecting air duct and the horizontal plane is in the range of 20 to 35°. The angle θ4 between the air inlet side shell of the air inlet chamber and the horizontal plane ranges from 50° to 75°.

12. The static classifier online powder return detection system according to claim 10, characterized in that, The design air volume of the multi-flow regulating main air duct accounts for 50-70% of the total air intake volume, and the design air velocity V1 of the multi-flow regulating main air duct is in the range of 12-16 m / s. The design wind speed Vpi range of the multi-flow regulating air distribution duct is 9 to 14 m / s.

13. A method for intelligent control of powder return coupled with multi-flow airflow in a static classifier, characterized in that, The static classifier powder return online detection system according to any one of claims 1 to 12 includes the following steps: Step 1: Control the first material distribution control valve to discharge the first portion of material discharged from the return powder outlet of the static classifier into the first metering device, and obtain the first data T1 measured by the first metering device; Step 2: Open the first single-pass control valve to allow the first portion of material to enter the screening device from the first metering device and be screened into the first coarse powder and the first fine powder, and allow the first fine powder obtained after screening to enter the second metering device. Step 3: Obtain the second data T2 of the first fine powder measured by the second metering device, and calculate the fine powder content P in the powder returned by the static classifier based on the ratio of the second data T2 to the first data T1. Step 4: Determine the relationship between the fine powder content P in the recycled powder and the preset fine powder content P0 in the recycled powder; When P≤P0, the control valve of the multi-flow regulating connection duct does not need to be adjusted; When P > P0, the regulation process is as follows: Step 401: Obtain the third data f1 detected by the online gas flow detection device; Step 402: Increase the opening of all multi-flow regulating branch pipe valves in proportion one from bottom to top, and decrease the opening of the multi-flow regulating main pipe valve in proportion two. Step 403: Obtain the fourth data f2 detected by the online gas flow detection device again, and calculate the absolute value of the difference between the fourth data f2 and the third data f1; the fourth data f2 is the gas flow data discharged from the collection device after the multi-flow regulating connecting duct is regulated; Determine whether the absolute value of the difference between the fourth data f2 and the third data f1 is within a preset error range; if it is determined that the absolute value of the difference between the fourth data f2 and the third data f1 is not within the preset error range, repeat steps 402 to 404 until it is determined that the difference between the fourth data f2 and the third data f1 is within the preset error range. Step 5: Repeat steps 1 to 4 until the fine powder content P is determined to be less than or equal to the fine powder content P0, thus completing one adjustment.

14. The intelligent control method for powder return coupling multi-flow air control in a static classifier according to claim 13, characterized in that, Also includes: In step 2, the first coarse powder obtained after screening is put into the material stabilization weighing bin; In step 3, after obtaining the second data T2 of the first fine powder measured by the second metering device, the second single-pass control valve is opened to allow the first fine powder in the second metering device to enter the elevator.

15. The intelligent control method for powder return coupling multi-flow air control in a static classifier according to claim 13, characterized in that, The ratio is in the range of 1 to 15%; The range of the ratio 2 is 1% to 10%.

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