A control method of a mixed waste plastic injection feeding system

Abstract

This invention provides a control method for a mixed waste plastic blowing and feeding system, comprising: performing feature extraction processing on several vibration data detected by each vibration sensor within a target time period to obtain a target feature vector corresponding to each vibration sensor within the target time period; matching and comparing the target feature vector corresponding to any key sensor with the predicted feature vector corresponding to the key sensor to obtain the vector similarity corresponding to the key sensor; sorting the vector similarities corresponding to several key sensors according to the decreasing order of the installation height of the fluidizing devices in the storage silos corresponding to several key sensors; if the values ​​of the sorted vector similarities show an overall decreasing trend, then at the end of the target time period, controlling several fluidizing devices in several silos and several air cannons to work simultaneously once, so as to automatically control the start and stop of several air cannons and reduce the waste of resource costs.

Description

Technical Field

[0001] This invention relates to the field of mixed waste plastic recycling technology, and in particular to a control method for a mixed waste plastic injection feeding system. Background Technology

[0002] Plastic recycling refers to the recycling and reuse of waste plastics after consumption. The main methods of plastic recycling are divided into physical methods, chemical methods, degradation recycling methods, and energy recovery methods. Typically, waste packaging plastics or plastic films are first dried, then processed into plastic flakes with a particle size of ≤5mm using a shredder. After iron and foreign matter removal, they are temporarily stored in a plastic flake storage bin, and then injected into a designated thermal reactor using a differential pressure fluidized bed spraying method. In the entire process described above, the use of differential pressure fluidized bed spraying for plastic sheet spraying results in large fluctuations in instantaneous flow rate due to pressure differential spraying, leading to low instantaneous accuracy. Furthermore, the amount of plastic sheets sprayed is affected by three variables: tank pressure, outlet valve opening, and secondary air supply, resulting in complex patterns and cumbersome control algorithms that require numerous empirical parameters for calculation. Consequently, the system's regulation characteristics and stability are poor. Pressure fluctuations during tank transfer also cause significant fluctuations in the total amount of plastic sheets sprayed. The numerous on / off valves and regulating valves, combined with the complex control algorithm, lead to numerous potential failure points and difficult maintenance. Moreover, since it is a fully manual or semi-automatic operation, operators need to adjust input parameters according to changes in the on-site process conditions, further complicating operation and maintenance. Furthermore, the aforementioned process of blowing plastic sheets involves a pressurized thermal reactor, resulting in a blowing pressure in the blowing tank that is significantly higher than the reactor's pressure. This causes phenomena such as bridging, adhesion to the walls, rat holes, and discontinuity of the plastic sheets within the blowing tank. Additionally, the lightweight and irregular nature of the plastic sheets, along with the fibers generated at the cut edges, leads to the plastic sheets adhering to the inner wall of the blowing tank and preventing free discharge. Moreover, because the scraper inside the blowing tank is a straight plate and the lower half of the powder hopper is conical, a gap exists between the scraper and the inner wall of the blowing tank. Therefore, when the plastic sheets, which have a certain level of moisture, are discharged from the less fluid powder, the rotating scraper exerts a force on the powder between the scraper and the inner wall of the blowing tank, causing the plastic sheets to be compacted against the inner wall of the powder hopper, resulting in no discharge. In summary, the existing differential pressure fluidized bed blowing method suffers from problems such as repeated manual assistance in material discharge, leading to low work efficiency. Summary of the Invention

[0003] To address the aforementioned technical problems, the technical solution adopted by this invention is as follows: According to one aspect of this application, a control method for a mixed waste plastic blowing and feeding system is provided, applied to the control system of the mixed waste plastic blowing and feeding system; the mixed waste plastic blowing and feeding system includes a storage bin, and a plurality of air cannons and fluidizing devices are arranged on the inner surface of the storage bin. The same set of air cannons and fluidizing devices are located in the same vibrating area, and there is no overlap between the plurality of vibrating areas. A vibration sensor is arranged in each vibrating area; the plurality of fluidizing devices operate simultaneously once every preset time interval; The control method for the mixed waste plastic blowing and feeding system includes the following steps: Step S100: Perform feature extraction processing on several vibration data detected by each vibration sensor within the target time period to obtain the target feature vector corresponding to each vibration sensor within the target time period. The target time period is a preset duration; the start time of the target time period is the moment when several silo fluidization devices last operated and several air cannons did not operate. Step S200: Match and compare the target feature vector corresponding to any key sensor with the predicted feature vector corresponding to the key sensor to obtain the vector similarity corresponding to the key sensor. The key sensor is the vibration sensor corresponding to the fluidization device of the silo, except for the fluidization device of the silo with the highest installation height in the storage silo. The predicted feature vector is obtained by predicting several vibration data detected by key sensors within a preset time period before the target time period; Step S300: Sort the vector similarity of several key sensors according to the decreasing order of the installation height of the fluidization device in the storage silo corresponding to several key sensors. Step S400: If the similarity values ​​of the sorted vectors show an overall decreasing trend, then at the end of the target time period, control the fluidization devices of several silos and the air cannons to work simultaneously once.

[0004] The present invention has at least the following beneficial effects: The control method of the mixed waste plastic blowing and feeding system of the present invention first performs feature extraction processing on several vibration data detected by each vibration sensor within a target time period to obtain the target feature vector corresponding to each vibration sensor within the target time period. Then, the target feature vector corresponding to any key sensor is matched and compared with the predicted feature vector corresponding to the key sensor to obtain the vector similarity corresponding to the key sensor. Then, according to the decreasing order of the setting height of the fluidizing devices in the storage silo corresponding to the key sensors, the vector similarity corresponding to the key sensors is sorted. If the values ​​of the similarity of the sorted vectors show an overall decreasing trend, then at the end of the target time period, the fluidizing devices in the storage silo and the air cannons are controlled to work simultaneously once. Otherwise, only the fluidizing devices in the storage silo are controlled to work, so as to automatically control the start and stop of the air cannons. When there is material adhering to the wall and causing blockage in the storage silo, the air cannons are activated to assist the fluidizing devices in blowing the material to achieve the purpose of material detachment from the wall. When the material flow in the storage silo is relatively smooth, only the fluidizing devices in the storage silo are activated to blow the material to reduce the waste of resource costs. Attached Figure Description

[0005] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0006] Figure 1 A flowchart of the control method for the mixed waste plastic blowing and feeding system provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of the mixed waste plastic blowing and feeding system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the material storage system provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the feeding system provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the rotary scraper arch-breaking ruler provided in an embodiment of the present invention; In the picture: 01. Material storage system; 1. Material storage silo; 2. Air cannon; 3. Material fluidization device; 4. Activated hopper; 5. Manual slide gate valve; 6. Feed pipe; 02. Feeding system; 7. Discharge dome valve; 8. First flexible section; 9. Inlet dome valve; 10. Pulsation tank body; 11. Weighing sensor; 13. Second flexible section; 14. Exhaust dome valve; 15. Tank pressure transmitter; 16. High level gauge; 17. Low level gauge; 18. Variable frequency vertical rotary feeder; 19. Outlet dome valve; 26. Rotary scraper arch-breaking strip; 12. Gas storage tank; 20. Mixing tee; 21. Third flexible joint; 22. Pressure transmitter for conveying pipeline; 23. Conveying pipeline; 24. Wear-resistant elbow; 25. Discharge bag filter. Detailed Implementation

[0007] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0008] This application proposes a control method for a mixed waste plastic blowing and feeding system, applicable to the control system of the mixed waste plastic blowing and feeding system, such as... Figure 2 As shown, the mixed waste plastic blowing and feeding system includes several feeding subsystems. Each feeding subsystem has the same internal structure and includes an interconnected storage system 01 and a feeding system 02. The storage system 01 and feeding system 02 of the same group are connected by a discharge pipe 6 (the discharge pipe 6 is made of seamless steel pipe, and the pipe diameter can be DN300). The discharge port of the feeding system 02 of each feeding subsystem is connected to the external reactor through a conveying pipe 23 (the conveying pipe 23 is made of seamless stainless steel pipe with polished inner surface, and the pipe diameter can be 50 mm, and the pipe wall thickness can be 3-5 mm). The following description uses the composition of one feeding subsystem as an example: like Figure 3 As shown, the material storage system 01 includes a material storage silo 1, an air cannon 2, a material fluidization device 3, an activated hopper 4, and a manual slide valve 5.

[0009] Storage silo 1 is a storage silo for shredded waste plastic film, playing a role in collecting and storing waste plastic film during the recycling process. The inlet of storage silo 1 is connected to an external crusher, and the material entering storage silo 1 is the shredded waste plastic film. Several air cannons 2 are set on the inner surface of the cone of storage silo 1. The air cannons 2 can be set opposite each other on the surface of storage silo 1 or at different heights (the air cannon in this application is a blower aerator that can release stored air in a sudden and high-energy manner. The compressed air is stored in a pressure vessel and released by a fast-opening valve, which can release all the compressed air in the pressure vessel in just 0.09 seconds, generating an air speed of over 1000 km / h and generating a force of nearly 18,000 Newtons). Several fluidization devices 3 are also set on the cone surface of storage silo 1. The number of fluidizing devices 3 in the silo can be equal to the number of air cannons 2. The fluidizing devices 3 and air cannons 2 can be used together. The fluidizing device 3 is a fluidizer (also called a silo flow aid, i.e., an arch-breaking device, commonly known as a "small umbrella" fluidizer). The fluidizing device 3 and air cannons 2 can be installed on the inner wall of the storage silo 1 at a location where waste plastic film shreds are prone to sticking to the wall. The activation hopper 4 is set at the outlet of the storage silo 1 (the activation hopper 4 is also called a vibrating hopper, which is an integrated arch-breaking feeding device). The manual slide valve 5 (the manual slide valve 5 is a manual spiral slide valve) is set at the outlet of the activation hopper 4. The manual slide valve 5 is connected to the discharge pipe 6. The material (i.e. waste plastic film shreds) in the storage silo 1 is controlled by the manual slide valve 5 to enter the discharge pipe 6 and then be transferred to the feeding system 02 through the discharge pipe 6.

[0010] Several vibrating material zones are pre-divided on the inner surface of the storage silo 1. Each vibrating material zone is equipped with an air cannon 2, a silo fluidization device 3, and a vibration sensor (the vibration sensor is used to detect the vibration signal in the vibrating material zone it is in). There is no overlap between the several vibrating material zones. Several silo fluidization devices 3 work simultaneously once every preset time interval. The start-up of the air cannon 2 is controlled by the control system of the mixed waste plastic blowing and feeding system.

[0011] The structures of the air cannon 2, the fluidizing device 3, and the activated hopper 4 are the same as those of the existing air cannon, fluidizer, and activated hopper, and their operating principles are also the same, so they will not be described in detail here.

[0012] like Figure 4 As shown, the feeding system 02 includes a discharge dome valve 7, a first flexible section 8, an inlet dome valve 9, a spray tank body 10, a weighing sensor 11, a second flexible section 13, an exhaust dome valve 14, a tank pressure transmitter 15, a high level gauge 16, a low level gauge 17, a frequency conversion vertical rotary feeder 18, and an outlet dome valve 19.

[0013] The inlet of the discharge dome valve 7 is connected to the discharge pipe 6 (the connection between the outlet of the manual slide valve 5 and the discharge pipe 6, and the connection between the inlet of the discharge dome valve 7 and the discharge pipe 6 are connected by flanges, and the connection is sealed with a flexible sealing gasket. The pressure setting of the discharge dome valve 7 is not less than 10 bar to adapt to the internal working pressure of 2 bar in the reactor). The outlet of the discharge dome valve 7 is connected to the inlet of the inlet dome valve 9 (the inlet dome valve 9 is a pneumatic dome valve, just like the discharge dome valve 7. The dome valve in this application is a special valve for powder, with air-filled sealing and a sealing ring made of silicone rubber, so the sealing effect is better than other types of valves) through the first flexible section 8 (the first flexible section 8 is made of rubber). The outlet of the inlet dome valve 9 is connected to the inlet of the spray tank body 10, so that the material in the discharge pipe 6 is transferred sequentially through the discharge dome valve 7, the first flexible section 8, and the inlet dome valve 9 (through free fall). The compressed nitrogen gas is transported to the main body 10 of the injection tank. The outlet of the main body 10 of the injection tank is connected to the inlet of the variable frequency vertical rotary feeder 18 (a flexible sealing gasket is provided at the connection surface between the main body 10 of the injection tank and the variable frequency vertical rotary feeder 18). The outlet of the variable frequency vertical rotary feeder 18 is connected to the inlet of the outlet dome valve 19. The outlet of the outlet dome valve 19 is connected to the first port of the mixing tee 20. The second port of the mixing tee 20 is connected to the conveying pipe 23 through the third flexible section 21. The third port of the mixing tee 20 is connected to the exhaust pipe of the gas storage tank 12. The mixing tee 20 is equipped with a guide plate to guide the compressed nitrogen gas conveyed by the gas storage tank 12 and the dust ash conveyed by the variable frequency vertical rotary feeder 18 to fully mix to form a dense phase conveying, which significantly reduces the flow resistance and enables the effective conveying distance of the material to reach 500-1500 meters without the need for a transfer station, thus meeting the conveying needs within the plant area of ​​a large chemical enterprise.

[0014] The function of the gas storage tank 12 is to store nitrogen and reduce the impact of large instantaneous flow of nitrogen during pressurization on the pressure fluctuation of the external nitrogen network. The volume of the gas storage tank 12 can be 5-10m³, and the design pressure can be 1.0-1.6MPa. The inlet of the gas storage tank 12 is connected to the factory's compressed nitrogen pipeline network through a pipeline. This pipeline is equipped with a pressure regulating valve to regulate the pressure of the nitrogen entering the gas storage tank 12 to 0.6-0.8MPa, so as to avoid pressure fluctuations in the gas storage tank 12, thereby overcoming the limitations of long-distance transportation and covering the needs of the chemical plant area.

[0015] The variable frequency vertical rotary feeder 18 is driven by an explosion-proof variable frequency geared motor with a protection rating of not less than IP54 and an explosion-proof rating of ExdIIBT4. The speed adjustment range of the variable frequency vertical rotary feeder 18 is 10-60 r / min, and the feeding rate adjustment range is 2~6 t / h. The diameter of the variable frequency vertical rotary feeder 18 can be 900 mm, and the height can be 300 mm. Figure 5As shown, the variable frequency vertical rotary feeder 18 is also equipped with a rotary scraper arch-breaking strip 26 at the discharge end. The size range of the rotary scraper arch-breaking strip 26 can be 500 mm to 750 mm. When the variable frequency vertical rotary feeder 18 rotates, it will drive the rotary scraper arch-breaking strip 26 to rotate. When the rotary scraper arch-breaking strip 26 rotates, it will move along the inner wall of the cone of the spray tank body 10 to remove the material adhering to the inner wall of the cone of the spray tank body 10 from the inner wall of the spray tank body 10.

[0016] The discharge dome valve 7 is an inflatable sealed dome valve with stable and reliable performance, simple maintenance, and long service life. The opening and closing of the discharge dome valve 7 is carried out in a non-contact manner between the valve body and the valve core. After closing, the unique inflatable sealing device in the valve body can automatically and firmly seal the internal channel of the valve and keep the conveying cavity on one side of the discharge dome valve 7 in a reliable pressure conveying state, which can ensure that the material does not malfunction during the conveying process and operates reliably. Due to the unique design of the internal components of the dome valve, the unobstructed flow of material in the valve body and the non-contact relative movement between the valve body and the valve core during the opening and closing process make the dome valve wear-free during material flow and valve opening and closing. The discharge dome valve 7 is used in conjunction with weighing and metering during the discharge process to isolate the material and ensure weighing accuracy.

[0017] Multiple air cannons 2 can also be installed on the cone of the blow-off tank body 10 to blow off the material adhering to the inner wall of the cone of the blow-off tank body 10.

[0018] Weighing sensor 11 (used to weigh the material inside the spray tank body 10), tank pressure transmitter 15 (used to detect the air pressure inside the spray tank body 10), high level gauge 16 and low level gauge 17 are installed on the surface of the spray tank body 10, and the installation height of high level gauge 16 is higher than that of low level gauge 17. For example, high level gauge 16 is installed at the top of spray tank body 10 and low level gauge 17 is installed at the bottom of spray tank body 10. Both high level gauge 16 and low level gauge 17 are tuning fork vibrating rod type level gauges used to detect the material at the corresponding installation position.

[0019] An exhaust dome valve 14 is located at the top of the blow-jet tank body 10. The outlet of the exhaust dome valve 14 is connected to the second flexible section 13, and the second flexible sections 13 of several feeding subsystems are all connected to the discharge bag filter 25. The pressure of the discharge bag filter 25 is not less than 0.5 MPa, and the interior of the discharge bag filter 25 uses polytetrafluoroethylene membrane filter bags. When the blow-jet tank body 10 is conveying materials, due to the long conveying distance and high resistance, the pressure of the reactor is above 0.2 MPa during operation, and the blowing conveying pressure can reach above 0.4 MPa. When the two blow-jet tank bodies 10 of the dual feeding subsystem are running alternately, the exhaust pressure is also above 0.4 MPa. Therefore, ordinary bag filters cannot meet the high-pressure exhaust requirements. Therefore, the discharge bag filter 25 of this application is a bag filter designed to be pressure-resistant and wear-resistant.

[0020] A pressure transmitter 22 is installed on the conveying pipeline 23 (for detecting the air pressure in the conveying pipeline 23), and a wear-resistant elbow 24 with a large radius of curvature is installed at the bend of the conveying pipeline 23. The angle of the wear-resistant elbow 24 can be 45° or 90°. The material of the wear-resistant elbow 24 is the same as that of the conveying pipeline 23. An electrostatic bridging device is installed on the conveying pipeline 23. The device uses a copper wire to reliably ground the conveying pipeline 23 and the wear-resistant elbow 24.

[0021] In the mixed waste plastic blowing feeding system of this application, the various conveying pipes and valves are connected by a sealed connection, and each flange connection uses a flexible sealing gasket to form a multi-seal structure, which greatly improves the sealing performance and eliminates safety and environmental hazards. It is used to realize the smooth feeding and long-distance blowing of waste plastic film shreds. The feeding dome valve 7, inlet dome valve 9, exhaust dome valve 14, and outlet dome valve 19 are all pneumatic dome valves, and their structures are the same as those of existing pneumatic dome valves, so they will not be described in detail here. The nitrogen in the gas storage tank 12 enters the feeding dome valve 7, inlet dome valve 9, exhaust dome valve 14, and outlet dome valve 19 through the outlet gas distribution pipe.

[0022] In practice, the waste plastic film shredded by an external crusher enters the storage silo 1. Because the shredded waste plastic film is lightweight and its surface is covered with lint, its flowability is poor, easily causing blockages. Therefore, to achieve smooth loading, the air cannon 2 and the silo fluidization device 3 need to be activated to achieve uniform flow at multiple points within the storage silo 1. The activation hopper 4 and the manual slide valve 5 are also activated. The vibration of the activation hopper 4 activates the material, allowing the activated material to fall through the manual slide valve 5 into the discharge pipe 6, effectively solving the problem of difficult material discharge from the silo. The manual slide valve 5 can be manually closed depending on the amount of material falling into the spray tank body 10. When the manual slide valve 5 is closed, the storage silo 1 is isolated from the spray tank body 10, and the material in the storage silo 1 will not fall into the spray tank body 10. When the material in the spray tank body 10 is low or needs to be loaded, the manual slide valve 5 is reopened. When loading begins, first open the exhaust dome valve 14. After the pressure inside the spray tank body 10 is released, open the inlet dome valve 9 and the discharge dome valve 7. This allows the material in the discharge pipe 6 to fall into the spray tank body 10 through the discharge dome valve 7, the first flexible section 8, and the inlet dome valve 9 in sequence. When the material in the spray tank body 10 reaches the upper limit (i.e., when the high level gauge 16 is triggered), close the above valves in sequence to stop loading. When the spray tank body 10 needs to transport the material to the reactor, open the outlet dome valve 19. This allows the material in the spray tank body 10 to be transported to the outlet dome valve 19 through the variable frequency vertical rotary feeder 18. The material in the outlet dome valve 19 and the nitrogen gas from the gas storage tank 12 enter the mixing tee 20. After mixing, the material enters the conveying pipe 23 through the third flexible section 21. The entire discharge process is interlocked, with stable performance and low leakage. It is suitable for unloading materials with light specific gravity, a lot of lint, and easy wall adhesion.

[0023] In addition, to achieve automatic control, this application can be controlled by a PLC (Programmable Logic Controller) control system. The pressure transmitter 22 is a monitoring device for the parameters of the conveyed gas. Based on the monitored data, the flow regulating device and related valves (discharge dome valve 7, inlet dome valve 9, exhaust dome valve 14, outlet dome valve 19) are adjusted through the PLC control system. The variable frequency vertical rotary feeder 18 is connected to a frequency converter, which is installed in the MCC (Motor Control Center) control system to adjust the speed to adapt to different material conveying volumes. The PLC control system, the MCC control system, and the connection with the corresponding components in this application are all prior art, so they will not be described in detail here.

[0024] The rotational speed of the variable frequency vertical rotary feeder 18 can be controlled within the range of 10-60 rpm by the MCC control system, corresponding to a feeding rate of 2-6 tons / hour. In conjunction with the pressure transmitter 22 of the conveying pipeline, the pressure of the conveying pipeline 23 is monitored in real time. When the pressure of the conveying pipeline 23 rises to 0.6MPa (blockage warning value), the PLC control system automatically reduces the rotational speed of the variable frequency vertical rotary feeder 18 to reduce the material concentration. When the pressure of the conveying pipeline 23 drops to 0.3MPa (low load value), the PLC control system automatically increases the rotational speed of the variable frequency vertical rotary feeder 18 to reduce the blockage rate of the material in the spray tank body 10 and significantly improve the material conveying stability.

[0025] The mixed waste plastic blowing and feeding system of the present invention is mainly aimed at waste plastics from recycled paper mills, packaging plastic films, agricultural flexible plastic mulch films, and waste plastics from municipal solid waste. It includes several feeding subsystems, each of which includes an interconnected storage system 01 and a feeding system 02. The outlet of the feeding system 02 of each feeding subsystem is connected to an external reactor through a conveying pipe 23. The storage system 01 includes a storage bin 1, and several air cannons 2 and a fluidizing device 3 are installed on the surface of the storage bin 1. The discharge port of the storage silo 1 is connected to the inlet of the feeding system 02 through the activation hopper 4. The material attached to the inner wall of the storage silo 1 is blown off by the air cannon 2 and the fluidization device 3, so that the material in the storage silo 1 can be smoothly transported to the feeding system 02. The material is then blown into the reactor through the feeding system 02 in a long distance and in a closed manner to realize the pneumatic blowing feeding for resource recycling. This overcomes the technical defects of the existing waste plastic film crushing feeding system, such as poor flow performance, easy clogging of the blowing, and short effective conveying distance.

[0026] Furthermore, by setting up multiple sets of air cannons 2 and material silo fluidization devices 3, the present invention can significantly improve the arch breaking effect, effectively eliminating the poor flowability, bridging, adhesion, and wall hanging phenomena of waste plastic film shreds. In addition, a rotating scraper arch breaking strip 26 is set on the variable frequency vertical rotary feeder 18 to make it difficult for the material in the spray tank body 10 to adhere to the inner wall, thereby forming multiple ways to ensure material discharge.

[0027] Furthermore, to reduce resource waste, the activation and deactivation of several air cannons 2 need to be automated. When material adheres to the walls of the storage silo 1, causing blockage, the air cannons 2 are activated to assist the fluidization device 3 in blowing the material away from the walls, thus achieving material detachment. When material flow within the storage silo 1 is relatively smooth, only the fluidization device 3 is activated to blow the material away, reducing resource consumption. Therefore, this application also proposes a control method for a mixed waste plastic blowing and feeding system. This control method is applied to the control system of the mixed waste plastic blowing and feeding system, such as... Figure 1 As shown, it includes the following steps: Step S100: Perform feature extraction processing on several vibration data detected by each vibration sensor within the target time period to obtain the target feature vector corresponding to each vibration sensor within the target time period. The target time period is a preset duration; the start time of the target time period is the moment when several silo fluidization devices 3 last worked and several air cannons 2 did not work, that is, the time period during which the air cannons 2 are not started each time.

[0028] The vibration data detected by the vibration sensor is the vibration data within the vibrating material area where the vibration sensor is located.

[0029] Furthermore, step S100 includes steps S110-S120: Step S110: Obtain several vibration data points detected by each vibration sensor within the target time period to obtain several target data lists A1, A2, ..., A g ,...,A f Where g = 1, 2, ..., f; f is the number of vibration sensors; A g This is the list of target data corresponding to the g-th vibration sensor; A g =(A g1 A g2 ,...,A gc ,...,A gd ); c=1,2,...,d; d is the number of data collection moments included in the target time period; the duration between any two adjacent data collection moments within the target time period is equal; A gc The vibration data detected by the g-th vibration sensor at the c-th data acquisition time in the target time period; Step S120, for A g Feature extraction and time-series feature encoding are performed on several vibration data within the target time period to obtain the target feature vector corresponding to the g-th vibration sensor within the target time period.

[0030] The feature encoding method for the target feature vector adopts the existing temporal feature encoding method.

[0031] Step S200: Match and compare the target feature vector corresponding to any key sensor with the predicted feature vector corresponding to the key sensor to obtain the vector similarity corresponding to the key sensor. The key sensor is the vibration sensor corresponding to the fluidized bed 3 of the silo 1, except for the fluidized bed 3 of the silo 1 which is installed at the highest height.

[0032] The predicted feature vector is obtained by predicting several vibration data detected by key sensors within a preset time period before the target time period.

[0033] Furthermore, step S200 includes steps S210-S270: Step S210: Based on the decreasing order of the installation height of the fluidizing devices 3 in the storage silo 1, sort the vibration sensors in the vibrating area where the fluidizing devices 3 are located to obtain a sorted sensor list B=(B1,B2,...,B...). g ,...,B f ); where B g This is the identifier for the g-th vibration sensor after sorting a number of vibration sensors. Step S220: Place B2,...,B f The corresponding vibration sensor was identified as the key sensor; Step S230, Obtain B g The corresponding vibration sensor detects several vibration data points within a key time period to obtain B. g Corresponding key data list E g ; Among them, E g =(E g1 E g2 ,...,E gc ,...,E gd ); E gc For B g The vibration data detected by the corresponding vibration sensor at the c-th data acquisition time in the critical time period; The duration of the critical time period is a preset duration, and the end time of the critical time period is the start time of the target time period; the duration between any two adjacent data collection moments within the critical time period is equal to the duration between any two adjacent data collection moments within the target time period.

[0034] Step S240, for E g Feature extraction and time-series feature encoding are performed on several vibration data points to obtain B. g The corresponding key feature vector F of the vibration sensor during the key time period g ; Step S250, F a-1 Input into the preset prediction model to obtain the B output of the prediction model. a The corresponding vibration sensor's predicted feature vector G a Where a = 2, ..., f; Step S260, Obtain B aThe corresponding target feature vector H of the vibration sensor a ; Step S270, for H a With G a Perform matching and comparison to obtain the corresponding vector similarity I. a .

[0035] The predicted feature vector is the feature vector of the key sensor when only the fluidization device 3 of the silo is activated during the target time period, which is predicted based on the vibration data of the key sensor during the key time period. The target feature vector is the feature vector corresponding to the actual vibration data collected by the key sensor during the target time period. By comparing the predicted feature vector and the target feature vector, it is determined whether the air cannon 2 needs to be activated.

[0036] The prediction model is determined according to steps S251-S253: Step S251, Obtain B a The first feature vector L corresponding to several vibration data points from the vibration sensor within the first time period. a ; The first time period begins when, within the historical time period, several silo fluidization devices 3 are operating and several air cannons 2 are not operating; the duration of the first time period is a preset duration; the end time of the historical time period is before the start time of the target time period.

[0037] Step S252, Obtain B a-1 The second feature vector M corresponding to several vibration data points from the vibration sensor during the second time period. a-1 ; The duration of the second time period is the preset duration, and the end time of the second time period is the start time of the first time period.

[0038] The method for determining the second feature vector is the same as the method for determining the target feature vector, and will not be repeated here.

[0039] Step S253, M a-1 As training samples, L a As output labels, supervised training is performed on the preset initial time series regression model to obtain the prediction model.

[0040] The training samples for the prediction model are the vibration data of each key sensor during the historical time period when only the silo fluidization device 3 is activated, so that the feature vector output by the prediction model only focuses on the application scenario of activating the silo fluidization device 3 without activating the air cannon 2.

[0041] Step S300: Sort the vector similarity of several key sensors according to the decreasing order of the installation height of the fluidization device 3 in the storage silo 1. The greater the vector similarity, the closer the vibration of the corresponding key sensor is to the target time period and the critical time period. Since the predicted feature vector is the predicted vector under the condition that air cannon 2 does not need to be turned on (i.e., no material adhering to the wall), the greater the vector similarity, the closer the blockage of the vibrating material area where the key sensor is located is to the predicted blockage without air cannon 2 being turned on during the target time period. In other words, there is no material adhering to the wall in the vibrating material area where the key sensor is located during the target time period, and there is no need to turn on air cannon 2 for vibration. Conversely, if the vector similarity is smaller, the greater the difference between the blockage of the vibrating material area where the key sensor is located during the target time period and the predicted blockage without air cannon 2 being turned on. This indicates that material adhering may have occurred in the vibrating material area where the key sensor is located during the target time period, causing a large change between the vibration data of this vibrating material area during the target time period and the predicted vibration data without air cannon 2 being turned on. In this case, it is necessary to consider turning on air cannon 2 to eliminate the impact of material adhering to the wall.

[0042] Step S400: If the similarity values ​​of the sorted vectors show an overall decreasing trend, then at the end of the target time period, control the fluidization devices 3 of the silos and the air cannons 2 to work simultaneously once. If the similarity values ​​of the sorted vectors show an overall decreasing trend, it indicates that the vector similarity is getting smaller and smaller, meaning that the material adhesion to the wall is more severe as you go down. Since the input data for the predicted feature vector is the vibration data of the vibrating material areas at different heights, and since several silo fluidization devices 3 are started simultaneously for vibration, after the vibrating material areas will generate aftershocks. There is force transmission between different vibrating material areas. Therefore, the vibration data corresponding to the lower-height vibrating material area is affected by the vibration of the higher-height vibrating material area. The lower the height of the vibrating material area, the greater the cumulative effect of force transmission. Therefore, the predicted feature vector not only considers the vibration data in the corresponding vibrating material area, but also considers the vibration influence brought by the other vibrating areas set at a height above the vibrating area, so that the obtained predicted feature vector is more consistent with the actual vibration scenario. Therefore, if the similarity values ​​of the sorted vectors show an overall decreasing trend, it indicates that the phenomenon of material adhesion to the wall has occurred in the storage silo 1. Therefore, when the silo fluidization device 3 is started again, the air cannon 2 is controlled to work simultaneously to blow off the material adhering to the wall.

[0043] Furthermore, step S400 includes steps S410-S430: Step S410: Traverse I2,...,Ia ,...,I f , if I a -I a+1 If I ≥ I0, then at the end of the target time period, control several silo fluidization devices 3 and several air cannons 2 to work simultaneously once; otherwise, execute step S420. Where I0 is the preset similarity difference threshold.

[0044] Step S420: If I2,...,I a ,...,I f In the given information, if the difference between the similarity of the preceding vector and the similarity of the following vector is less than I0, then for I2,...,I... a ,...,I f Perform linear curve fitting to obtain the corresponding similarity change curve; Step S430: If the first derivative of the similarity change curve is less than zero, then at the end of the target time period, control several silo fluidization devices 3 and several air cannons 2 to work simultaneously once; otherwise, at the end of the target time period, control several silo fluidization devices 3 to work simultaneously once.

[0045] The control method of the mixed waste plastic blowing and feeding system of the present invention first performs feature extraction processing on several vibration data detected by each vibration sensor within a target time period to obtain the target feature vector corresponding to each vibration sensor within the target time period. Then, the target feature vector corresponding to any key sensor is matched and compared with the predicted feature vector corresponding to the key sensor to obtain the vector similarity corresponding to the key sensor. Then, according to the decreasing order of the setting height of the fluidizing devices in the storage silo corresponding to the key sensors, the vector similarity corresponding to the key sensors is sorted. If the values ​​of the similarity of the sorted vectors show an overall decreasing trend, then at the end of the target time period, the fluidizing devices in the storage silo and the air cannons are controlled to work simultaneously once. Otherwise, only the fluidizing devices in the storage silo are controlled to work, so as to automatically control the start and stop of the air cannons. When there is material adhering to the wall and causing blockage in the storage silo, the air cannons are activated to assist the fluidizing devices in blowing the material to achieve the purpose of material detachment from the wall. When the material flow in the storage silo is relatively smooth, only the fluidizing devices in the storage silo are activated to blow the material to reduce the waste of resource costs.

[0046] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A control method for a mixed waste plastic blowing and feeding system, characterized in that, A control system for a mixed waste plastic blowing and feeding system; the mixed waste plastic blowing and feeding system includes a storage silo (1), and several sets of air cannons (2) and silo fluidization devices (3) are arranged on the inner surface of the storage silo (1). The same set of air cannons (2) and silo fluidization devices (3) are located in the same vibrating area, and there is no overlap between the several vibrating areas. A vibration sensor is arranged in each vibrating area; several silo fluidization devices (3) work simultaneously once every preset time interval; The control method for the mixed waste plastic blowing and feeding system includes the following steps: Step S100: Perform feature extraction processing on several vibration data detected by each vibration sensor within the target time period to obtain the target feature vector corresponding to each vibration sensor within the target time period. The duration of the target time period is the preset duration; the start time of the target time period is the moment when the fluidization devices (3) of the silos last worked and the air cannons (2) did not work. Step S200: Match and compare the target feature vector corresponding to any key sensor with the predicted feature vector corresponding to the key sensor to obtain the vector similarity corresponding to the key sensor. The key sensor is the vibration sensor corresponding to the fluidized bed fluidization device (3) of the storage silo (1) except for the fluidized bed fluidization device (3) with the highest installation height in the storage silo (1); The predicted feature vector is obtained by predicting several vibration data detected by key sensors within a preset time period before the target time period; Step S300: Sort the vector similarity of the key sensors according to the decreasing order of the setting height of the fluidized bed device (3) corresponding to the key sensors in the storage bin (1); Step S400: If the similarity values ​​of the sorted vectors show an overall decreasing trend, then at the end of the target time period, control the fluidization devices (3) of the silos and the air cannons (2) to work simultaneously once.

2. The method according to claim 1, characterized in that, Step S100 includes: Step S110: Obtain several vibration data points detected by each vibration sensor within a target time period to obtain several target data lists A1, A2, ..., A g ,...,A f Where g = 1, 2, ..., f; f is the number of vibration sensors; A g This is the target data list corresponding to the g-th vibration sensor; A g =(A g1 A g2 ,...,A gc ,...,A gd ); c=1,2,...,d; d is the number of data collection moments included in the target time period; the duration between any two adjacent data collection moments in the target time period is equal; A gc The vibration data detected by the g-th vibration sensor at the c-th data acquisition time in the target time period; Step S120, for A g Feature extraction and time-series feature encoding are performed on several vibration data within the target time period to obtain the target feature vector corresponding to the g-th vibration sensor within the target time period.

3. The method according to claim 2, characterized in that, Step S200 includes: Step S210: According to the decreasing order of the installation height of the fluidizing devices (3) in the storage silo (1), sort the vibration sensors in the vibrating area where the fluidizing devices (3) are located to obtain a sorted sensor list B=(B1,B2,...,B g ,...,B f ); where B g This is the identifier corresponding to the g-th vibration sensor after sorting a number of vibration sensors; Step S220: Place B2,...,B f The corresponding vibration sensor was identified as a key sensor; Step S230, Obtain B g The vibration data detected by the corresponding vibration sensor during the key time period are used to obtain B. g Corresponding key data list E g ; Among them, E g =(E g1 E g2 ,...,E gc ,...,E gd ); E gc For B g The vibration data detected by the vibration sensor at the c-th data acquisition time in the critical time period; The duration of the key time period is the preset duration, and the end time of the key time period is the start time of the target time period; the duration between any two adjacent data collection moments within the key time period is equal to the duration between any two adjacent data collection moments within the target time period. Step S240, for E g Feature extraction and time-series feature encoding are performed on several vibration data points to obtain B. g The corresponding key feature vector F of the vibration sensor during the key time period g ; Step S250, F a-1 The input is fed into a preset prediction model to obtain the B output by the prediction model. a The corresponding predicted feature vector G of the vibration sensor a Where a = 2, ..., f; Step S260, Obtain B a The target feature vector H corresponding to the vibration sensor a ; Step S270, for H a With G a Perform matching and comparison to obtain the corresponding vector similarity I. a .

4. The method according to claim 3, characterized in that, The prediction model is determined according to the following steps: Step S251, Obtain B a The first feature vector L corresponding to several vibration data points of the vibration sensor within the first time period. a ; The start time of the first time period is the time when several of the silo fluidization devices (3) are working and several of the air cannons (2) are not working during the historical time period; the duration of the first time period is the preset duration; the end time of the historical time period is before the start time of the target time period. Step S252, Obtain B a-1 The second feature vector M corresponding to several vibration data points of the vibration sensor within the second time period. a-1 ; The duration of the second time period is the preset duration, and the end time of the second time period is the start time of the first time period; Step S253, M a-1 As training samples, L a As output labels, supervised training is performed on the preset initial time series regression model to obtain the prediction model.

5. The method according to claim 4, characterized in that, Step S400 includes: Step S410: Traverse I2,...,I a ,...,I f , if I a -I a+1 If I0 is greater than or equal to I0, then at the end of the target time period, control several of the fluidized bed devices (3) and several of the air cannons (2) to work simultaneously once; where I0 is a preset similarity difference threshold.

6. The method according to claim 5, characterized in that, Step S410 further includes: Step S420: If I2,...,I a ,...,I f In the given information, if the difference between the similarity of the preceding vector and the similarity of the following vector is less than I0, then for I2,...,I... a ,...,I f Perform linear curve fitting to obtain the corresponding similarity change curve; Step S430: If the first derivative of the similarity change curve is less than zero, then at the end of the target time period, control several of the silo fluidization devices (3) and several of the air cannons (2) to work simultaneously once; otherwise, at the end of the target time period, control several of the silo fluidization devices (3) to work simultaneously once.

7. The method according to claim 6, characterized in that, The mixed waste plastic blowing feeding system includes several feeding subsystems. Each feeding subsystem has the same structure. Each feeding subsystem includes a storage system (01) and a feeding system (02) that are interconnected. The storage system (01) includes the storage bin (1). The outlet of the storage bin (1) of each feeding subsystem is connected to the inlet of the corresponding feeding system (02) through the activation hopper (4). The outlet of the feeding system (02) of each feeding subsystem is connected to the external reactor through the conveying pipe (23).

8. The method according to claim 7, characterized in that, The feeding system (02) includes a blow tank body (10), the inlet of the blow tank body (10) is connected to the outlet of the inlet dome valve (9), the inlet of the inlet dome valve (9) is connected to the outlet of the discharge dome valve (7) through the first flexible section (8), and the inlet of the discharge dome valve (7) is connected to the outlet of the storage system (01).

9. The method according to claim 8, characterized in that, The discharge port of the spray tank body (10) is equipped with a variable frequency vertical rotary feeder (18), and the outlet of the variable frequency vertical rotary feeder (18) is connected to the inlet of the outlet dome valve (19). The outlet of the outlet dome valve (19) is connected to the conveying pipeline (23) through a mixing tee (20).

10. The method according to claim 9, characterized in that, The variable frequency vertical rotary feeder (18) is equipped with a rotary scraper arch-breaking strip (26) on the feeding end.

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