A three-stage series crushing system and process suitable for alternative fuels

Abstract

The application discloses a three-stage series crushing system and process suitable for alternative fuel, relates to the technical field of alternative fuel production, and comprises a first-stage double-shaft coarse crusher, a second-stage double-shaft medium crusher and a third-stage single-shaft fine crusher which are connected in series, wherein the system is provided with a load detection unit to obtain the operation load of the coarse crusher / medium crusher, a discharge particle size detection unit to monitor the fine crushing degree of the fine crusher, a bypass feeding mechanism to control a first discharge port through a three-way distribution valve, so that the third-stage single-shaft fine crusher can be directly fed, and a control unit which is in communication connection with each detection unit, the three-way distribution valve and the drive motors of the medium crusher and the fine crusher, so as to realize intelligent regulation and control of the crushing path and process parameters according to the material characteristics and operation state.

Description

Technical Field

[0001] This invention relates to the field of alternative fuel production technology, specifically to a three-stage tandem crushing system and process suitable for alternative fuels. Background Technology

[0002] In the cement industry, the demand for alternative fuels (AFRs) has increased significantly, and waste textile materials have become one of the mainstream alternative fuels for cement kilns due to their stable calorific value and wide availability.

[0003] Currently, the industry commonly uses a two-stage crushing process consisting of one twin-shaft crusher and one single-shaft crusher, but this process has significant drawbacks in actual production.

[0004] 1. The primary twin-shaft coarse crushing capacity is limited, and a large number of oversized particles and tough materials are directly fed into the single-shaft fine crusher, resulting in high impact load, frequent stalling, and severe torque fluctuations.

[0005] 2. A large amount of electrical energy in a single-shaft crusher is wasted on repeated squeezing, idling, and unblocking, resulting in high power consumption per ton and a low proportion of useful power.

[0006] 3. When large, tough lumps enter the twin-shaft crusher, the high-speed, light-load operating conditions make it extremely susceptible to impact overload. If the load intensity of subsequent processes is not reduced in time, the impact load will be transmitted and accumulated downstream along the production line.

[0007] 4. It is difficult to determine whether the output particle size of a single-shaft crusher deviates from the qualified range required by the process. The current practice is to rely on operators to take samples and screen them regularly, and adjust the parameters based on the offline test results, which is inefficient.

[0008] Therefore, it is necessary to provide a three-stage tandem crushing system and process suitable for alternative fuels to solve the above problems. Summary of the Invention

[0009] The present invention aims to solve the above-mentioned technical problems and provide a three-stage tandem crushing system and process suitable for alternative fuels.

[0010] The technical solution adopted in this invention is as follows:

[0011] Firstly, a three-stage tandem crushing system suitable for alternative fuels is provided, comprising:

[0012] A primary twin-shaft coarse crusher, a secondary twin-shaft medium crusher, and a tertiary single-shaft fine crusher are connected in series.

[0013] A load detection unit is installed on the primary twin-shaft coarse crusher and / or the secondary twin-shaft intermediate crusher, and is configured to acquire the operating load signal of the primary twin-shaft coarse crusher and / or the secondary twin-shaft intermediate crusher;

[0014] The discharge particle size detection unit is located at the discharge end of the three-stage single-shaft fine crusher and is configured to acquire detection information characterizing the degree of fine crushing of the discharge.

[0015] The bypass feeding mechanism has a first discharge port and a three-way distribution valve. The three-way distribution valve is configured to control the opening and closing of the first discharge port, which is directly connected to the feed end of the three-stage single-shaft fine crusher.

[0016] The control unit is communicatively connected to the load detection unit, the discharge particle size detection unit, the three-way material distribution valve, the drive motor of the two-stage twin-shaft intermediate crusher, and the drive motor of the three-stage single-shaft fine crusher.

[0017] Furthermore, as a preferred embodiment, the three-stage single-shaft fine crusher includes a casing and a discharge arc plate disposed in the casing, a cutting blade is disposed above the discharge arc plate, and the discharge arc plate has a discharge hole;

[0018] The discharge particle size detection unit includes:

[0019] Two rotating rollers are arranged symmetrically on the left and right sides, and the rotating rollers are rotatably mounted in the machine housing and located below the discharge arc plate;

[0020] Each of the rollers is fixed with an arc-shaped seat, and a telescopic rod is hinged between the arc-shaped seat and the machine housing;

[0021] Each of the rotating rollers is hinged with a detection arc plate. The end of the detection arc plate away from the rotating roller is connected to the corresponding arc-shaped seat through an elastic support member. Detection holes are distributed on the detection arc plate.

[0022] Furthermore, preferably, the diameter of the discharge hole is equal to the diameter of the detection hole;

[0023] The elastic support is equipped with a weight sensor.

[0024] Furthermore, preferably, the surface of the arc-shaped seat is provided with high-pressure nozzles corresponding to the detection holes;

[0025] The telescopic rod is configured to drive the detection arc plate to oscillate, and the high-pressure nozzle is configured to spray fluid toward the detection hole to clear the detection hole;

[0026] The telescopic rod is also configured to drive the detection arc plate to oscillate the discharge arc plate;

[0027] The control unit is also configured to: receive the real-time power signal or current signal of the drive motor of the three-stage single-shaft fine crusher, and comprehensively determine the deviation trend of the discharge particle size based on the real-time power signal or current signal combined with the output signal of the weight sensor, and accordingly perform closed-loop correction of the operating parameters of the two-stage double-shaft intermediate crusher.

[0028] Furthermore, as a preferred embodiment, the load detection unit includes a torque sensor disposed on the drive shaft of the primary twin-shaft coarse crusher and / or the secondary twin-shaft intermediate crusher.

[0029] Furthermore, as a preferred embodiment, the feed end of the bypass feeding mechanism is connected to the discharge end of the primary twin-shaft coarse crusher, and the discharge end of the bypass feeding mechanism forms the first discharge port.

[0030] The three-way feed valve has a first valve position and a second valve position;

[0031] With the first valve in the first position, the first discharge port is closed, and the discharge from the first-stage twin-shaft coarse crusher enters the third-stage single-shaft fine crusher via the second-stage twin-shaft intermediate crusher.

[0032] With the second valve position, the first discharge port is opened, and part of the incoming material enters the three-stage single-shaft fine crusher directly through the bypass feeding mechanism.

[0033] Furthermore, preferably, the control unit is configured as follows:

[0034] Within a preset acquisition time window after the primary twin-shaft coarse crusher starts, the torque timing signal acquired by the load detection unit is received, and time-domain features and / or frequency-domain features are extracted from the torque timing signal. Based on the pre-stored material classification model, the toughness category of the current batch of materials is determined.

[0035] Based on the toughness category, the corresponding combination of target rotation speed, blade gap and feed speed is retrieved from the preset process parameter library, and the initial operating parameters of the secondary twin-shaft intermediate crusher and / or the tertiary single-shaft fine crusher are set accordingly.

[0036] Furthermore, preferably, the control unit is configured as follows:

[0037] The operating load of the primary twin-shaft coarse crusher is monitored in real time. When the operating load exceeds a first preset threshold and the duration exceeds a preset time, the secondary twin-shaft intermediate crusher is controlled to switch from a first operating speed to a second operating speed lower than the first operating speed. After the operating load falls back below the first preset threshold, the secondary twin-shaft intermediate crusher is controlled to return to the first operating speed.

[0038] If the current batch of material is determined to be a low-toughness brittle material based on the toughness category, and the current load of the three-stage single-shaft fine crusher is lower than the preset load limit, the three-way material distribution valve is controlled to open the first discharge port, so that the three-stage single-shaft fine crusher can simultaneously receive material from the two-stage double-shaft intermediate crusher and material from the bypass feeding mechanism.

[0039] Secondly, a three-stage tandem crushing process suitable for alternative fuels is provided, comprising the following steps:

[0040] S1. Within the preset acquisition time window after the primary twin-shaft coarse crusher starts, the torque time sequence signal is acquired through the load detection unit, and the time domain features and / or frequency domain features are extracted from the torque time sequence signal. Based on the pre-stored material classification model, the toughness category of the current batch of materials is determined.

[0041] S2. Based on the toughness category, retrieve the corresponding combination of target rotation speed, blade gap and feed speed from the preset process parameter library, and set the initial operating parameters of the secondary twin-shaft intermediate crusher and / or the tertiary single-shaft fine crusher accordingly.

[0042] S3. Monitor the operating load of the primary twin-shaft coarse crusher obtained by the load detection unit in real time. When the operating load exceeds the first preset threshold and the duration exceeds the preset time, control the secondary twin-shaft intermediate crusher to switch from the first operating speed to a second operating speed lower than the first operating speed through the control unit, so as to buffer the impact load of large pieces of high-toughness materials with low speed and high torque; and control the secondary twin-shaft intermediate crusher to return to the first operating speed after the operating load falls back to below the first preset threshold.

[0043] S4. The discharge particle size detection unit obtains detection information characterizing the degree of fine crushing of the discharge. When the comprehensive judgment result shows that the discharge particle size deviates from the preset qualified range, the control unit performs closed-loop correction on the operating parameters of the secondary dual-shaft intermediate crusher.

[0044] The time-domain features include at least one of the mean torque, peak torque, torque variance, and torque rise slope; the frequency-domain features include the energy proportion of the torque signal within a preset frequency band and / or the dominant frequency component; the toughness category includes high-toughness waste textiles, medium-toughness mixed textiles, and low-toughness brittle textiles.

[0045] Compared with the prior art, the present invention provides a three-stage tandem crushing system and process suitable for alternative fuels, which has the following beneficial effects:

[0046] In this invention, when the primary twin-shaft coarse crusher encounters large, highly resilient materials and its operating load continuously exceeds the limit, the control unit does not directly shut down the equipment. Instead, it actively intervenes to adjust the speed of the intermediate crusher, switching it from a high-speed, light-load mode to a low-speed, high-torque mode. This reduces the feeding rate of the secondary twin-shaft intermediate crusher, giving the primary twin-shaft coarse crusher more time to gradually decompose the highly resilient lumps. Once the load on the coarse crusher returns to a safe range, the secondary twin-shaft intermediate crusher immediately resumes its normal high-speed operation, thus avoiding shutdown and protecting all parts of the transmission chain from overload damage.

[0047] In this invention, when the current batch of material is determined to be a low-toughness brittle material based on the toughness category, and the current load of the three-stage single-shaft fine crusher still has a margin, the control unit instructs the three-way distribution valve of the bypass feeding mechanism to open the first discharge port, so that part of the material discharged from the first-stage twin-shaft coarse crusher bypasses the second-stage twin-shaft intermediate crusher and directly flows into the third-stage single-shaft fine crusher, reducing the ineffective wear of the intermediate crushing blades, and at the same time, utilizing the load margin of the third-stage single-shaft fine crusher to increase the overall production capacity.

[0048] In this invention, the discharge particle size detection unit set at the discharge end of the three-stage single-shaft fine crusher continuously acquires discharge particle size characterization information, and makes a comprehensive judgment by combining it with the real-time power / current signal of the drive motor of the three-stage single-shaft fine crusher. Once a particle size deviation trend is detected, the operating parameters of the two-stage double-shaft intermediate crusher are closed-loop compensated and corrected without stopping the machine. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the existing technology;

[0050] Figure 2 This is a schematic diagram of a three-stage tandem crushing system suitable for alternative fuels;

[0051] Figure 3 This is a schematic diagram of the discharge particle size detection unit;

[0052] Figure 4 A flowchart of a three-stage tandem crushing process suitable for alternative fuels;

[0053] In the diagram: 1. Primary twin-shaft coarse crusher; 2. First conveyor belt; 3. Secondary twin-shaft intermediate crusher; 4. Second conveyor belt; 5. Tertiary single-shaft fine crusher; 51. Chassis; 52. Discharge arc plate; 53. Rotary roller; 54. Arc-shaped seat; 55. Telescopic rod; 56. High-pressure nozzle; 57. Elastic support component; 58. Detection arc plate. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the present invention clearer, the various technical solutions of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the terms "first," "second," etc., used below are only used to distinguish different components or parts, and do not constitute a limitation on the order, importance, or number of components or parts. The same reference numerals in the accompanying drawings indicate the same or similar components.

[0055] Example: In this embodiment of the invention, please refer to... Figures 1-4 A three-stage tandem crushing system suitable for alternative fuels is provided, including a primary twin-shaft coarse crusher 1, a secondary twin-shaft medium crusher 3, a tertiary single-shaft fine crusher 5, a load detection unit, a discharge particle size detection unit, a bypass feeding mechanism, and a control unit.

[0056] A primary twin-shaft coarse crusher 1, a secondary twin-shaft intermediate crusher 3, and a tertiary single-shaft fine crusher 5 are connected in series along the material flow direction. The discharge end of the primary twin-shaft coarse crusher 1 is connected to the feed end of the secondary twin-shaft intermediate crusher 3 via a first conveyor belt 2, and the discharge end of the secondary twin-shaft intermediate crusher 3 is connected to the feed end of the tertiary single-shaft fine crusher 5 via a second conveyor belt 4. The three-stage series configuration achieves a progressively decreasing particle size: the primary twin-shaft coarse crusher 1 undertakes the primary crushing of the original large pieces of material, crushing the material to an intermediate particle size; the secondary twin-shaft intermediate crusher 3 further crushes the material; and the tertiary single-shaft fine crusher 5 completes the final fine crushing, so that the discharge particle size meets the specifications required for alternative fuel entering the kiln or forming process.

[0057] The load detection unit is installed on the primary twin-shaft coarse crusher 1 and / or the secondary twin-shaft intermediate crusher 3. Its function is to acquire the operating load signal of the crusher. The operating load signal is a key physical quantity characterizing the intensity of the crusher's current operating conditions. When the incoming material contains large, high-toughness materials, the cutting resistance of the cutters increases, the torque of the drive shaft rises, and the current of the drive motor increases accordingly. Therefore, the load signal can directly or indirectly reflect the crushability of the incoming material and its impact intensity on the crushing system. The load detection unit can be installed only on the primary twin-shaft coarse crusher 1, or simultaneously on the primary twin-shaft coarse crusher 1 and the secondary twin-shaft intermediate crusher 3, thereby obtaining more complete load distribution information.

[0058] The discharge particle size detection unit is located at the discharge end of the three-stage single-shaft fine crusher 5. Its function is to acquire detection information characterizing the degree of fineness of the discharge. Unlike offline screening in the laboratory, the discharge particle size detection unit is installed at the discharge port or discharge chute of the fine crusher. During production, it acquires discharge particle size-related signals online in real time, providing feedback input for subsequent closed-loop control. The detection information characterizing the degree of fineness of the discharge can take various forms, such as screening the discharge through a detection plate / detection arc plate with a specific aperture, or indirectly reflecting the particle size distribution by weighing the retained material.

[0059] The bypass feeding mechanism has a first discharge port and a three-way distribution valve. The three-way distribution valve is an actuator that changes the material flow direction. It has an internal swingable valve plate or rotatable valve core. By switching the position of the valve plate / valve core, the connection or blockage of each outlet channel can be achieved. The three-way distribution valve is configured to control the opening and closing of the first discharge port, which is directly connected to the feed end of the three-stage single-shaft fine crusher 5 via a chute or sluice. This direct connection means that after the material is discharged from the first discharge port through the bypass feeding mechanism, it does not need to pass through the two-stage twin-shaft intermediate crusher 3, but directly enters the feed port of the three-stage single-shaft fine crusher 5.

[0060] The control unit is the decision-making and control center of the entire system. It communicates with the load detection unit, discharge particle size detection unit, three-way feed valve, drive motor of the two-stage twin-shaft intermediate crusher 3, and drive motor of the three-stage single-shaft fine crusher 5. At the hardware level, the control unit can be an industrial-grade programmable logic controller (PLC), an embedded industrial computer, or a dedicated controller with multiple I / O interfaces and communication interfaces. Communication connections can utilize industrial fieldbus protocols (such as PROFINET, EtherCAT, Modbus TCP / RTU) to achieve real-time, deterministic signal acquisition and command issuance.

[0061] In this embodiment, the three-stage single-shaft fine crusher 5 includes a casing 51 and a discharge arc plate 52 disposed in the casing 51. A cutting blade is disposed above the discharge arc plate 52, and the discharge arc plate 52 has a discharge hole.

[0062] The discharge particle size detection unit includes:

[0063] Two symmetrically arranged rotating rollers 53 are rotatably disposed in the housing 51 and located below the discharge arc plate 52;

[0064] Each of the rollers 53 is fixed with an arc-shaped seat 54, and a telescopic rod 55 is hinged between the arc-shaped seat 54 and the housing 51. The telescopic rod 55 can be any one of a hydraulic telescopic cylinder, a pneumatic cylinder, or an electric push rod.

[0065] Each of the rotating rollers 53 is hinged with a detection arc plate 58. The end of the detection arc plate 58 away from the rotating roller 53 is connected to the corresponding arc-shaped seat 54 through an elastic support member 57. Detection holes are distributed on the detection arc plate 58.

[0066] Specifically, the end of the detection arc plate 58 closest to the rotating roller 53 is hinged to the shaft of the rotating roller 53 via a hinge pin, allowing the detection arc plate 58 to swing around the hinge point. The end of the detection arc plate 58 furthest from the rotating roller 53 is connected to the corresponding arc-shaped seat 54 via an elastic support member 57. The elastic support member 57 serves a dual function of elastic suspension and force transmission. In a static state, the elastic support member 57 suspends the detection arc plate 58 above the arc-shaped seat 54, maintaining it in an initial posture. When the discharged material falls onto the detection arc plate 58, the weight and impact force of the material cause the elastic support member 57 to elastically deform, resulting in a slight displacement of the detection arc plate 58. The elastic support member 57 can be selected from any one of a coil spring, a disc spring, a rubber elastomer, or a spring-damper assembly.

[0067] Furthermore, the diameter of the discharge hole is equal to the diameter of the detection hole;

[0068] The elastic support 57 is equipped with a weight sensor. Specific implementation methods include, but are not limited to, the following examples: the elastic support 57 is an elastic body with built-in strain gauges. The strain gauges are attached to the deformation-sensitive area of ​​the elastic body. When the elastic support 57 deforms due to the weight of the material it traps, the resistance value of the strain gauges changes accordingly. Furthermore, the control unit needs to perform low-pass filtering or moving average processing on the weight signal to extract the static component.

[0069] Furthermore, the surface of the arc-shaped seat 54 is provided with high-pressure nozzles 56 corresponding to the detection holes;

[0070] The telescopic rod 55 is configured to drive the detection arc plate 58 to oscillate, and the high-pressure nozzle 56 is configured to spray fluid toward the detection hole to clear the detection hole;

[0071] The telescopic rod 55 is also configured to drive the detection arc plate 58 to oscillate the discharge arc plate 52;

[0072] The control unit is also configured to: receive the real-time power signal or current signal of the drive motor of the three-stage single-shaft fine crusher 5, and comprehensively determine the deviation trend of the discharge particle size based on the real-time power signal or current signal combined with the output signal of the weight sensor, and accordingly perform closed-loop correction of the operating parameters of the two-stage double-shaft intermediate crusher 3.

[0073] When the control unit sends a series of high-frequency pulse commands to the control valve of the telescopic rod 55, the telescopic rod 55 rapidly reciprocates with a small stroke and a high frequency. This high-frequency, micro-amplitude vibration is transmitted to the detection arc plate 58 via the arc-shaped seat 54 and the elastic support 57, causing the detection arc plate 58 to oscillate. In this oscillation mode, material particles clogging the detection hole loosen and fall off under the combined action of inertial force and vibration shear stress, thus restoring the detection hole to its original permeability. Simultaneously, the high-pressure nozzle 56 is configured to spray fluid (e.g., liquid) towards the detection hole to clear it. Oscillation and spraying can be performed synchronously to enhance the unclogging effect, or they can be performed alternately, flexibly combined according to the severity of the clogging.

[0074] The telescopic rod 55 is also configured to drive the detection arc plate 58 to oscillate the discharge arc plate 52. This is another operating mode of the telescopic rod 55: the control unit sends a command to the control valve of the telescopic rod 55 to extend its stroke. The telescopic rod 55 drives the arc seat 54 and the rotating roller 53 to rotate around the axis of the rotating roller with a larger amplitude, causing the end of the detection arc plate 58 away from the rotating roller 53 to swing upward until the upper surface of the detection arc plate 58 contacts or impacts the lower surface of the discharge arc plate 52, transmitting vibration and impact force to the discharge arc plate 52, causing the material blocked in the discharge hole to loosen and fall off. Afterward, the telescopic rod 55 retracts in the opposite direction, and the detection arc plate 58 returns to its initial position. This action can be performed periodically to prevent and clear blockages in the discharge arc plate 52.

[0075] Of course, in non-detection mode, the control unit sends a command for a larger stroke to the control valve of the telescopic rod 55. The telescopic rod 55 drives the arc seat 54 and the rotating roller 53 to rotate around the axis of the rotating roller with a larger amplitude, so that the end of the detection arc plate 58 away from the rotating roller 53 swings downward, so that the detection arc plate 58 does not participate in the detection.

[0076] In this embodiment, the load detection unit includes a torque sensor disposed on the drive shaft of the primary twin-shaft coarse crusher 1 and / or the secondary twin-shaft intermediate crusher 3.

[0077] Specific types of torque sensors include, but are not limited to: resistance strain gauge torque sensors, magnetoelastic torque sensors, and photoelectric torque sensors. Torque signal is the most direct physical quantity characterizing the crushing load. The resistance torque of the cutting tool on the material is directly reflected as the drive shaft torque. The signal response speed is fast and unaffected by electrical factors such as motor efficiency and voltage fluctuations. Preferably, the torque sensor is installed on the drive shaft of the primary twin-shaft coarse crusher 1.

[0078] In this embodiment, the feed end of the bypass feeding mechanism is connected to the discharge end of the primary twin-shaft coarse crusher 1, and the discharge end of the bypass feeding mechanism forms the first discharge port.

[0079] The three-way feed valve has a first valve position and a second valve position;

[0080] With the first valve in the first position, the first discharge port is closed, and the discharge from the first-stage twin-shaft coarse crusher 1 enters the third-stage single-shaft fine crusher 5 via the second-stage twin-shaft intermediate crusher 3.

[0081] With the second valve position, the first discharge port is opened, and part of the incoming material enters the three-stage single-shaft fine crusher 5 directly through the bypass feeding mechanism.

[0082] In this embodiment, the control unit is configured as follows:

[0083] Within a preset acquisition time window after the first-stage twin-shaft coarse crusher 1 is started, the torque time-series signal acquired by the load detection unit is received, and time-domain features and / or frequency-domain features are extracted from the torque time-series signal. Based on the pre-stored material classification model, the toughness category of the current batch of materials is determined.

[0084] Based on the toughness category, the corresponding combination of target rotation speed, blade gap and feed speed is retrieved from the preset process parameter library, and the initial operating parameters of the secondary twin-shaft intermediate crusher 3 and / or the tertiary single-shaft fine crusher 5 are set accordingly.

[0085] It should be explained that the material classification model described is a pattern recognition model pre-trained and calibrated through offline experiments before the system is put into production operation. Example of the training method: When materials of different known toughness categories (such as high-toughness waste textiles, medium-toughness mixed materials, and low-toughness brittle materials) are fed into the coarse crusher, their torque time-series signals are collected and feature vectors are extracted, labeled with category names, and a training dataset is constructed. Then, a supervised learning algorithm (such as Support Vector Machine (SVM), K-Nearest Neighbors (KNN), Random Forest, or shallow Artificial Neural Network (ANN)) is used to train the classification model. After training, the model parameters and structure are permanently stored in the non-volatile memory (such as EEPROM, Flash, or SSD) of the control unit. During actual operation, the control unit inputs the real-time extracted feature vectors into the pre-stored model, and the model outputs the toughness category discrimination result of the current batch of materials.

[0086] The aforementioned process parameter library is a multidimensional parameter mapping table or database that stores the optimal combination of operating parameters corresponding to different toughness categories. For example, for high-toughness waste textiles, it is recommended that the secondary twin-shaft intermediate crusher 3 use a lower speed, a larger blade gap, and a lower feed rate to provide greater torque reserve and a longer material residence time, ensuring that the high-toughness material is fully torn rather than simply crushed; for low-toughness brittle materials, it is recommended that the secondary twin-shaft intermediate crusher 3 use a higher speed, a smaller blade gap, and a higher feed rate to utilize the brittle material's tendency to break under high-speed impact to increase production capacity. These parameter combinations can be pre-obtained and entered into the parameter library through process experiments (orthogonal experiments, response surface methodology) or simulations based on crushing mechanisms (such as discrete element method (DEM) simulations).

[0087] In this embodiment, the control unit is configured as follows:

[0088] The operating load of the primary twin-shaft coarse crusher 1 is monitored in real time. When the operating load exceeds a first preset threshold and the duration exceeds a preset time, the secondary twin-shaft intermediate crusher 3 is controlled to switch from a first operating speed to a second operating speed lower than the first operating speed. After the operating load falls back to below the first preset threshold, the secondary twin-shaft intermediate crusher 3 is controlled to return to the first operating speed.

[0089] When the current batch of material is determined to be a low-toughness brittle material according to the toughness category, and the current load of the three-stage single-shaft fine crusher 5 is lower than the preset load limit, the three-way material distribution valve is controlled to open the first discharge port, so that the three-stage single-shaft fine crusher 5 can simultaneously receive material from the two-stage double-shaft intermediate crusher 3 and material from the bypass feeding mechanism.

[0090] This embodiment also provides a three-stage tandem crushing process suitable for alternative fuels, including the following steps:

[0091] S1. Within the preset acquisition time window after the first-stage twin-shaft coarse crusher 1 is started, the torque time sequence signal is acquired through the load detection unit, and the time domain features and / or frequency domain features are extracted from the torque time sequence signal. Based on the pre-stored material classification model, the toughness category of the current batch of materials is determined.

[0092] S2. Based on the toughness category, retrieve the corresponding combination of target rotation speed, blade gap and feed speed from the preset process parameter library, and set the initial operating parameters of the secondary twin-shaft intermediate crusher 3 and / or the tertiary single-shaft fine crusher 5 accordingly.

[0093] S3. Monitor the operating load of the primary twin-shaft coarse crusher 1 obtained by the load detection unit in real time. When the operating load exceeds the first preset threshold and the duration exceeds the preset time, control the secondary twin-shaft intermediate crusher 3 to switch from the first operating speed to a second operating speed lower than the first operating speed through the control unit, so as to buffer the impact load of large pieces of high toughness materials with low speed and high torque; and control the secondary twin-shaft intermediate crusher 3 to return to the first operating speed after the operating load falls back to below the first preset threshold.

[0094] S4. The discharge particle size detection unit obtains detection information characterizing the degree of fine crushing of the discharge. When the comprehensive judgment result shows that the discharge particle size deviates from the preset qualified range, the control unit performs closed-loop correction on the operating parameters of the secondary dual-shaft intermediate crusher 3.

[0095] The four steps form a complete intelligent crushing control closed loop in terms of timing. S1 and S2 are executed at the initial stage of batch startup, belonging to the feedforward open-loop control stage; S3 and S4 are executed continuously throughout the entire batch operation, belonging to the online closed-loop control stage. The combination of feedforward and closed-loop control enables the system to have both the ability to respond quickly to sudden changes in incoming materials and the ability to continuously compensate for slow changes.

[0096] In step S1, the time-domain features include at least one of the mean torque, peak torque, torque variance, and torque rise slope; the frequency-domain features include the energy proportion of the torque signal within a preset frequency band and / or the dominant frequency component; and the toughness category includes high-toughness waste textiles, medium-toughness hybrids, and low-toughness brittle materials.

[0097] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A three-stage tandem crushing system suitable for alternative fuels, characterized in that, include: A primary twin-shaft coarse crusher (1), a secondary twin-shaft medium crusher (3), and a tertiary single-shaft fine crusher (5) are connected in series. A load detection unit is installed on the primary twin-shaft coarse crusher (1) and / or the secondary twin-shaft intermediate crusher (3) and is configured to acquire the operating load signal of the primary twin-shaft coarse crusher (1) and / or the secondary twin-shaft intermediate crusher (3); The discharge particle size detection unit is located at the discharge end of the three-stage single-shaft fine crusher (5) and is configured to acquire detection information characterizing the degree of fine crushing of the discharge. The bypass feeding mechanism has a first discharge port and a three-way distribution valve. The three-way distribution valve is configured to control the opening and closing of the first discharge port. The first discharge port is directly connected to the feed end of the three-stage single-shaft fine crusher (5). The control unit is communicatively connected to the load detection unit, the discharge particle size detection unit, the three-way material distribution valve, the drive motor of the secondary dual-shaft medium crusher (3), and the drive motor of the tertiary single-shaft fine crusher (5).

2. The system according to claim 1, characterized in that, The three-stage single-shaft fine crusher (5) includes a casing (51) and a discharge arc plate (52) disposed in the casing (51). A cutting blade is disposed above the discharge arc plate (52), and the discharge arc plate (52) has a discharge hole. The discharge particle size detection unit includes: Two rotating rollers (53) are arranged symmetrically on the left and right sides. The rotating rollers (53) are rotatably disposed in the machine box (51) and located below the discharge arc plate (52); Each of the rollers (53) is fixed with an arc-shaped seat (54), and a telescopic rod (55) is hinged between the arc-shaped seat (54) and the housing (51). Each of the rotating rollers (53) is hinged with a detection arc plate (58). The end of the detection arc plate (58) away from the rotating roller (53) is connected to the corresponding arc seat (54) through an elastic support (57). Detection holes are distributed on the detection arc plate (58).

3. The system according to claim 2, characterized in that, The diameter of the discharge hole is equal to the diameter of the detection hole; A weight sensor is provided in the elastic support (57).

4. The system according to claim 3, characterized in that, The surface of the arc-shaped seat (54) is provided with high-pressure nozzles (56) corresponding to the detection holes. The telescopic rod (55) is configured to drive the detection arc plate (58) to oscillate, and the high-pressure nozzle (56) is configured to spray fluid toward the detection hole to clear the detection hole; The telescopic rod (55) is also configured to drive the detection arc plate (58) to oscillate the discharge arc plate (52); The control unit is also configured to: receive the real-time power signal or current signal of the drive motor of the three-stage single-shaft fine crusher (5), and comprehensively determine the deviation trend of the discharge particle size based on the real-time power signal or current signal combined with the output signal of the weight sensor, and accordingly perform closed-loop correction of the operating parameters of the two-stage double-shaft medium crusher (3).

5. The system according to claim 1, characterized in that, The load detection unit includes a torque sensor installed on the drive shaft of the primary twin-shaft coarse crusher (1) and / or the secondary twin-shaft intermediate crusher (3).

6. The system according to claim 1, characterized in that, The feed end of the bypass feeding mechanism is connected to the discharge end of the primary twin-shaft coarse crusher (1), and the discharge end of the bypass feeding mechanism forms the first discharge port. The three-way feed valve has a first valve position and a second valve position; When the first valve is in the first position, the first discharge port is closed, and the discharge of the first-stage twin-shaft coarse crusher (1) enters the third-stage single-shaft fine crusher (5) through the second-stage twin-shaft medium crusher (3). In the second valve position, the first discharge port is opened, and part of the incoming material enters the three-stage single-shaft fine crusher (5) directly through the bypass feeding mechanism.

7. The system according to claim 1, characterized in that, The control unit is configured to: Within the preset acquisition time window after the first-stage twin-shaft coarse crusher (1) is started, the torque timing signal obtained by the load detection unit is received, the time domain features and / or frequency domain features of the torque timing signal are extracted, and the toughness category of the current batch of materials is determined based on the pre-stored material classification model. Based on the toughness category, the corresponding combination of target rotation speed, blade gap and feed speed is retrieved from the preset process parameter library, and the initial operating parameters of the secondary twin-shaft medium crusher (3) and / or the tertiary single-shaft fine crusher (5) are set accordingly.

8. The system according to claim 7, characterized in that, The control unit is configured to: The operating load of the primary twin-shaft coarse crusher (1) is monitored in real time. When the operating load exceeds the first preset threshold and the duration exceeds the preset time, the secondary twin-shaft medium crusher (3) is controlled to switch from the first operating speed to the second operating speed, which is lower than the first operating speed. After the operating load falls back to below the first preset threshold, the secondary twin-shaft medium crusher (3) is controlled to return to the first operating speed. When the current batch of material is determined to be a low-toughness brittle material according to the toughness category, and the current load of the three-stage single-shaft fine crusher (5) is lower than the preset load limit, the three-way material distribution valve is controlled to open the first discharge port, so that the three-stage single-shaft fine crusher (5) can simultaneously receive material from the two-stage double-shaft intermediate crusher (3) and material from the bypass feeding mechanism.

9. A three-stage tandem crushing process suitable for alternative fuels, characterized in that, The three-stage cascade crushing system according to any one of claims 1 to 8 includes the following steps: S1. Within the preset acquisition time window after the first-stage twin-shaft coarse crusher (1) is started, the torque timing signal is acquired through the load detection unit, and the time domain features and / or frequency domain features are extracted from the torque timing signal. Based on the pre-stored material classification model, the toughness category of the current batch of materials is determined. S2. Based on the toughness category, retrieve the corresponding combination of target rotation speed, blade gap and feed speed from the preset process parameter library, and set the initial operating parameters of the secondary twin-shaft medium crusher (3) and / or the tertiary single-shaft fine crusher (5) accordingly. S3. Monitor the operating load of the primary twin-shaft coarse crusher (1) obtained by the load detection unit in real time. When the operating load exceeds the first preset threshold and the duration exceeds the preset time, control the secondary twin-shaft medium crusher (3) to switch from the first working speed to a second working speed lower than the first working speed through the control unit, so as to buffer the impact load of large pieces of high toughness materials with low speed and high torque; and control the secondary twin-shaft medium crusher (3) to return to the first working speed after the operating load falls back to below the first preset threshold. S4. Obtain detection information characterizing the degree of fine crushing of the output through the output particle size detection unit. When the comprehensive judgment result shows that the output particle size deviates from the preset qualified range, the operating parameters of the secondary dual-shaft medium crusher (3) are closed-loop corrected through the control unit.

10. The process according to claim 9, characterized in that, In step S1, the time-domain features include at least one of the mean torque, peak torque, torque variance, and torque rise slope; the frequency-domain features include the energy proportion of the torque signal within a preset frequency band and / or the dominant frequency component; and the toughness category includes high-toughness waste textiles, medium-toughness hybrids, and low-toughness brittle materials.

Images