Reworked material fine grading equipment and grading method

Abstract

The invention relates to the field of pavement asphalt recovery equipment, and provides reclaimed material fine grading equipment and a grading method. Comprising a raw material bin, a first belt conveyor arranged at the output end of the raw material bin, a coarse-grade screen arranged at the output end of the first belt conveyor, a second belt conveyor arranged at the output end of the coarse-grade screen, a vertical shaft impact crusher arranged at the output end of the second belt conveyor and a third belt conveyor arranged at the output end of the vertical shaft impact crusher. The elevator is arranged at the output end of the third belt conveyor, the V-shaped air-drying screening device is arranged at the output end of the elevator, the circular vibrating screen is connected with the output end of the V-shaped air-drying screening device, the high-frequency vibrating mesh screen is connected with the output end of the circular vibrating screen, and the fourth belt conveyor is arranged at the output ends of the circular vibrating screen and the high-frequency vibrating mesh screen. The reworked material screening device has the advantages that reworked materials can be finely screened into multi-grade materials, it is ensured that false particles do not appear in the reworked materials of all grades after final screening, and the conditions of material blocking and material sticking in the screening process can also be prevented.

Description

Technical Field

[0001] The invention relates to the technical field of road asphalt recycling equipment, and in particular to a recycled material fine grading device and a grading method. Background Art

[0002] Recycling Asphalt Pavement (RAP) refers to the process of excavating or milling the road surface to recycle old materials, crushing and screening the old materials, adding some new aggregates and new asphalt to remix them, and adding regeneration agents when necessary, so as to obtain a recycled asphalt mixture that meets the performance requirements of high-grade highways and is used for paving the road surface or base layer.

[0003] At present, the screening method commonly used for old materials (i.e. recycled materials) is to directly feed the recycled materials into a vibrating screen, and use the vibrating screen to screen the recycled materials into recycled materials of various particle sizes and stack them separately, such as a grading and screening device and screening system for asphalt recycled materials disclosed in the Chinese invention patent application with application number CN201710639481.4; at the same time, for large particles (such as particles larger than 25mm), the recycled materials usually enter the roller crusher or the impact crusher for crushing, and the crushed recycled materials will be returned to the vibrating screen through the feeding loop. However, the existing screening treatment scheme has the following defects: 1. There is a large proportion of false particles (i.e. recycled material agglomerates) in each grade of the screened recycled materials. When added to the asphalt mixture mixing equipment for use, it will cause major quality problems, such as large variations in grading and asphalt content, affecting the performance of asphalt pavement; 2. Because the recycled materials are sprinkled with water for dust suppression during milling, the water content in the recycled materials is high, which makes the equipment prone to problems such as screen sticking and chute blocking, thereby affecting the normal use of the equipment. In view of the above-mentioned problems, the inventor of this case conducted in-depth research on the issue, which led to the creation of this case. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a recycled material fine grading device and a grading method to solve the problem that the existing screening device is prone to quality problems and sticky material blockage due to the presence of a large proportion of false particles after screening.

[0005] The present invention is achieved in that: In the first aspect, a recycled material fine grading equipment includes a raw material bin, a first belt conveyor arranged at the output end of the raw material bin, a coarse grade screen arranged at the output end of the first belt conveyor, a second belt conveyor arranged at the output end of the coarse grade screen, a vertical shaft impact crusher arranged at the output end of the second belt conveyor, a third belt conveyor arranged at the output end of the vertical shaft impact crusher, an elevator arranged at the output end of the third belt conveyor, a V-shaped air-drying screen arranged at the output end of the elevator, a circular vibrating screen connected to the output end of the V-shaped air-drying screen, a high-frequency vibrating mesh screen connected to the output end of the circular vibrating screen, and a fourth belt conveyor arranged at the output ends of the circular vibrating screen and the high-frequency vibrating mesh screen.

[0006] Furthermore, the V-shaped air-drying screener includes an outer shell and a V-shaped impact structure; a screening chamber is formed in the outer shell, and the V-shaped impact structures are arranged in the screening chamber from top to bottom; a material inlet is provided at the top of the outer shell at a position corresponding to the V-shaped impact structure, and a large particle outlet is provided at the bottom of the outer shell at a position corresponding to the V-shaped impact structure; the outer shell is also provided with a fine particle outlet, a first air inlet and a first air outlet, the first air inlet is located on either side of the V-shaped impact structure, the fine particle outlet and the first air outlet are located on the other side of the V-shaped impact structure, and the fine particle outlet is provided at the bottom of the outer shell, and the first air outlet is provided at the top of the outer shell; A convex portion with a triangular cross-section is formed on the inner bottom of the outer shell between the fine particle outlet and the large particle outlet.

[0007] Further, it also includes a bag filter, a cyclone tower, an induced draft fan and a chimney; The input end of the bag filter is connected to the first air outlet through an air outlet pipe, the output end of the bag filter is connected to the input end of the cyclone tower, and the output end of the cyclone tower is connected to the input end of the induced draft fan; the chimney is connected to the output end of the induced draft fan, and the first air inlet is also connected to the chimney through a return air duct.

[0008] Furthermore, the V-shaped impact structure includes two rows of wear-resistant steel plates spaced from top to bottom, a material channel is left between the two rows of wear-resistant steel plates, the midpoint lines of the two rows of wear-resistant steel plates are two parallel oblique lines, and the two rows of wear-resistant steel plates are staggered and arranged in a V-shaped distribution.

[0009] Furthermore, a second air inlet is provided at the feed end of the vertical shaft impact crusher, and a second air outlet is provided at the discharge end of the vertical shaft impact crusher; both the circular vibrating screen and the high-frequency vibrating mesh screen are provided with dust output ports; the dust output ports of the circular vibrating screen and the high-frequency vibrating mesh screen and the second air outlet of the vertical shaft impact crusher are connected to the first air inlet through an air inlet pipe.

[0010] Furthermore, it also includes a feeding ring, a return belt conveyor and a roller crusher; The coarse grade screen has a first material output end for outputting fine material and a second material output end for outputting coarse material, and the input end of the second belt conveyor is connected with the first material output end; the input end of the double-roll crusher is connected with the second material output end, and the output end of the double-roll crusher is connected with the input end of the loading ring through the return belt conveyor, and the output end of the loading ring is connected with the first belt conveyor.

[0011] Furthermore, the circular vibrating screen has a third material output end for outputting a first-grade fine material, a fourth material output end for outputting a second-grade fine material, and a fifth material output end for outputting a third-grade fine material, and the first-grade fine material is larger than the second-grade fine material, and the second-grade fine material is larger than the third-grade fine material; the fifth material output end is connected to the input end of the high-frequency vibrating screen, and the third material output end and the fourth material output end are each connected to a fourth belt conveyor.

[0012] Furthermore, the high-frequency vibrating mesh screen has a sixth material output end for outputting a first-grade fine material, a seventh material output end for outputting a second-grade fine material, and an eighth material output end for outputting a third-grade fine material, and the first-grade fine material is larger than the second-grade fine material, and the second-grade fine material is larger than the third-grade fine material; a collecting hopper is provided below the high-frequency vibrating mesh screen at a position corresponding to the eighth material output end, and the fine particle outlet is connected to the collecting hopper; the sixth material output end, the seventh material output end and the output end of the collecting hopper are each connected to a fourth belt conveyor.

[0013] In a second aspect, a method for finely grading recycled materials is provided, the grading method comprising the following steps: The recycled material output from the raw material bin is conveyed to the coarse screen through the first belt conveyor, and the recycled material with a particle size less than 40 mm is screened out by the coarse screen and output to the second belt conveyor; The recycled material is conveyed to the vertical shaft impact crusher through the second belt conveyor for breaking up, and the broken recycled material is conveyed to the elevator through the third belt conveyor, and the elevator lifts the recycled material and outputs it to the V-type air-drying screener; The recycled material is air-dried, dehydrated and screened into two grades by using a V-shaped air-drying screen, and the recycled material with a particle size of more than 2 mm is conveyed to a circular vibrating screen for further screening; the recycled material is screened into three grades by the circular vibrating screen, and the finest grade of recycled material is conveyed to a high-frequency vibrating screen for further screening, and the remaining two grades of recycled material are each output through a fourth belt conveyor; the recycled material is further screened into three grades by a high-frequency vibrating screen, and the finest grade of recycled material is mixed with the recycled material with a particle size of less than 2 mm output by the V-shaped air-drying screen and output through a fourth belt conveyor, and the remaining two grades of recycled material are each output through a fourth belt conveyor.

[0014] Furthermore, the classification method further comprises the following steps: The recycled materials with a particle size of more than 40 mm screened by the coarse screen are transported to the roller crusher for crushing, and the crushed recycled materials are transported to the feeding ring through the return belt conveyor, and the crushed recycled materials are transported back to the first belt conveyor through the feeding ring; The induced draft fan is used to draw the dust and water vapor output by the V-type air-drying filter into the bag dust collector for dust removal, and then enters the cyclone tower for water removal; a part of the treated hot dry air is discharged through the chimney, and the other part of the hot dry air is transported back to the first air inlet of the V-type air-drying filter for recycling.

[0015] By adopting the technical solution of the present invention, at least the following beneficial effects are achieved: 1. Before the recycled material is transported to the V-type air-drying screener for screening, the vertical shaft impact crusher is used to break up the recycled material to ensure that no false particles will appear in each grade of recycled material after the final screening, thereby avoiding major quality problems in subsequent use and ensuring the performance of the asphalt pavement.

[0016] 2. Before using the circular vibrating screen and high-frequency vibrating mesh screen for screening, use a V-type air-drying screen to air-dry and dehydrate the recycled material, and directly output the recycled material with a particle size less than 2mm without entering the circular vibrating screen and high-frequency vibrating mesh screen, which can prevent the circular vibrating screen and high-frequency vibrating mesh screen from clogging and sticking during the screening process.

[0017] 3. Through the cooperation of V-type air-drying screen, circular vibrating screen and high-frequency vibrating mesh screen, the recycled materials can be finely screened into multiple grades, which is helpful to realize large-proportion addition application and ensure the stability of the grading and asphalt content of the produced recycled asphalt mixture, thereby ensuring product quality.

[0018] 4. The first air outlet of the V-shaped air-drying filter is connected to the bag dust collector, the cyclone tower, the induced draft fan and the chimney in sequence, and the chimney is connected to the first air inlet of the V-shaped air-drying filter. In the specific operation, the bag dust collector and the cyclone tower can be used to remove dust and water vapor generated during the operation to obtain low-temperature dry air, and the treated low-temperature dry air can be transported back to the first air inlet of the V-shaped air-drying filter for recycling, so as to air-dry the recycled material passing through the V-shaped air-drying filter.

[0019] 5. By adopting the design of the V-shaped impact structure of the present invention, on the one hand, it can ensure that the recycled material with a particle size of more than 2 mm will continuously collide with the wear-resistant steel plate in the process of falling down through the material channel, so that the recycled material can be better dispersed; on the other hand, the residence time of the recycled material in the V-shaped impact structure can be increased, thereby ensuring that the low-temperature dry air can better air-dry the recycled material.

[0020] 6. By opening a second air inlet at the feed end of the vertical shaft impact crusher and a second air outlet at the discharge end of the vertical shaft impact crusher, external cold air can enter the interior of the vertical shaft impact crusher through the second air inlet during operation, thereby cooling the vertical shaft impact crusher. That is, using air cooling technology to cool the interior of the vertical shaft impact crusher can prevent the recycled material from sticking to the impact cavity and the rotor, which helps to increase the service life; at the same time, the dust outlets of the circular vibrating screen and the high-frequency vibrating mesh screen and the second air outlet of the vertical shaft impact crusher are connected to the V-shaped air drying screen. The V-type air-drying screen is connected to the first air inlet of the screen. On the one hand, the dust generated by the circular vibrating screen, high-frequency vibrating mesh screen and vertical shaft impact crusher can be sucked into the bag dust collector and cyclone tower for dust removal and water removal. On the other hand, the rotating friction of the recycled material in the vertical shaft impact crusher and the relative friction during the operation of the recycled material will generate heat. After the heat is released into the air, it can ensure that the temperature of the dry air after being treated by the bag dust collector and the cyclone tower is higher than the external ambient temperature, thereby ensuring that the low-temperature dry air transported back to the V-type air-drying screen can play a role in drying and dehydrating the recycled material. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with embodiments with reference to the accompanying drawings.

[0022] Figure 1 This is a front view of a reclaimed material fine classification device of the present invention; Figure 2 This is a rear view of a reclaimed material fine classification device of the present invention; Figure 3 It is a top view of a reclaimed material fine classification device of the present invention; Figure 4 yes Figure 3 The structural diagram along the BB direction; Figure 5 It is a state diagram of the V-shaped air-drying screener in the process of air-drying and screening recycled materials in the present invention; Figure 6 It is the internal structure diagram of the V-shaped air-drying screener in the present invention; Figure 7 It is a structural diagram of the vertical shaft impact crusher of the present invention.

[0023] Description of reference numerals: Recycled material fine classification equipment 100; Raw material warehouse 1; A first belt conveyor 21, a second belt conveyor 22, a third belt conveyor 23, and a fourth belt conveyor 24; Coarse screen 3; Vertical shaft impact crusher 4, second air inlet 41, second air outlet 42; Hoist 5; V-shaped air-drying screener 6, outer shell 61, screening chamber 611, material inlet 612, large particle outlet 613, fine particle outlet 614, first air inlet 615, return air duct 6151, first air outlet 616, raised portion 617, air inlet duct 618, V-shaped impact structure 62, wear-resistant steel plate 621, material channel 622; Circular vibrating screen 7; High frequency vibrating screen 8, collecting hopper 81; Bag filter 91, air outlet pipe 911, cyclone tower 92, induced draft fan 93, chimney 94; Feeding ring 101, return belt conveyor 102, double roller crusher 103. DETAILED DESCRIPTION

[0024] In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0025] It should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing these embodiments and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. In addition, the terms "first", "second", etc., etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. Embodiment 1

[0026] See also Figures 1 to 7As shown, the present invention provides a recycled material fine grading equipment 100, which includes a raw material bin 1, a first belt conveyor 21 arranged at the output end of the raw material bin 1, a coarse screen 3 arranged at the output end of the first belt conveyor 21, a second belt conveyor 22 arranged at the output end of the coarse screen 3, a vertical shaft impact crusher 4 arranged at the output end of the second belt conveyor 22, a third belt conveyor 23 arranged at the output end of the vertical shaft impact crusher 4, an elevator 5 arranged at the output end of the third belt conveyor 23, a V-shaped air-drying screen 6 arranged at the output end of the elevator 5, a circular vibrating screen 7 connected to the output end of the V-shaped air-drying screen 6, a high-frequency vibrating mesh screen 8 connected to the output end of the circular vibrating screen 7, and a fourth belt conveyor 24 arranged at the output ends of the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8. Wherein: the raw material bin 1 is used for temporarily storing recycled materials, and the raw material bin 1 controls the feeding amount by controlling the motor speed with a frequency converter; the first belt conveyor 21 is used for conveying the recycled materials output from the raw material bin 1 to the coarse-grade screen 3; the coarse-grade screen 3 is used for coarsely screening the recycled materials into two grades of materials, one of which has a particle size of more than 40 mm and the other has a particle size of less than 40 mm; the second belt conveyor 22 is used for conveying the recycled materials with a particle size of less than 40 mm after screening to the vertical shaft impact crusher 4; the vertical shaft impact crusher 4 is used for breaking up the recycled materials so that no false particles appear in each grade of recycled materials after the final screening; the third belt conveyor 23 is used for conveying the scattered recycled materials to the elevator 5; the elevator 5 is used to lift the recycled materials and convey them to the V-type Air-drying screener 6; the V-shaped air-drying screener 6 is used to air-dry and dehydrate the recycled material and screen the recycled material into two grades, one of which has a particle size of less than 2 mm, and the other has a particle size of more than 2 mm; the circular vibrating screen 7 is used to screen the recycled material with a particle size of more than 2 mm output by the V-shaped air-drying screener 6 into three grades, and the finest grade of recycled material is conveyed to the high-frequency vibrating mesh screen 8, and the other two grades of recycled material are directly output; the high-frequency vibrating mesh screen 8 is used to continue to screen the recycled material into three grades, and the finest grade of recycled material is mixed with the recycled material with a particle size of less than 2 mm output by the V-shaped air-drying screener 6 for output, and the recycled material at the other two ends is directly output; the fourth belt conveyor 24 is used to convey each grade of recycled material to a designated area.

[0027] By adopting the above technical solution of the present invention, at least the following beneficial effects are achieved: 1. Before the recycled material is conveyed to the V-shaped air-drying screener 6 for screening, the vertical shaft impact crusher 4 is used to break up the recycled material, which can ensure that no false particles will appear in each grade of recycled material after the final screening, thereby avoiding major quality problems in subsequent use and ensuring the performance of the asphalt pavement.

[0028] 2. Before using the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 for screening, the V-shaped air-drying screen 6 is used to air-dry and remove water from the recycled material, and the recycled material with a particle size less than 2 mm is directly output without entering the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8, which can prevent the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 from being blocked or sticky during the screening process.

[0029] 3. Through the cooperation of the V-shaped air-drying screener 6, the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8, the recycled material can be finely screened into multiple grades, which is helpful to realize large-proportion addition application and ensure the stability of the gradation and asphalt content of the produced recycled asphalt mixture, thereby ensuring product quality.

[0030] In some embodiments of the present invention, please refer to Figure 5 and Figure 6 As shown, the V-shaped air-drying screener 6 includes an outer shell 61 and a V-shaped impact structure 62; a screening chamber 611 is formed in the outer shell 61, and the V-shaped impact structure 62 is arranged in the screening chamber 611 from top to bottom; a material inlet 612 is provided at the top of the outer shell 61 at a position corresponding to the V-shaped impact structure 62, and a large particle outlet 613 is provided at the bottom of the outer shell 61 at a position corresponding to the V-shaped impact structure 62. When in use, the recycled material output by the elevator 5 is input into the V-shaped air-drying screener 6 through the material inlet 612, and the input recycled material will collide with the V-shaped impact structure 62 to be further dispersed, and the recycled material with a particle size of more than 2 mm after screening is output through the large particle outlet 613; The outer shell 61 is also provided with a fine particle outlet 614, a first air inlet 615 and a first air outlet 616. The first air inlet 615 is located on either side of the V-shaped impact structure 62, the fine particle outlet 614 and the first air outlet 616 are located on the other side of the V-shaped impact structure 62, and the fine particle outlet 614 is arranged at the bottom of the outer shell 61, and the first air outlet 616 is arranged at the top of the outer shell 61. During operation, low-temperature dry air needs to be introduced into the outer shell 61 from the first air inlet 615. The low-temperature dry air can not only dry and dehydrate the recycled material in the process of passing through the V-shaped impact structure 62, but also can bring the recycled material with a particle size less than 2 mm out of the V-shaped impact structure 62, and make the recycled material with a particle size less than 2 mm fall down to the fine particle outlet 614 at the bottom of the outer shell 61 for discharge, and at the same time, the low-temperature dry air, dust and water vapor are output through the first air outlet 616 at the top of the outer shell 61.

[0031] In the specific implementation of the present invention, a raised portion 617 with a triangular cross-section is formed on the inner bottom of the outer shell 61 between the fine particle outlet 614 and the large particle outlet 613 to ensure that the recycled material is discharged either from the fine particle outlet 614 or from the large particle outlet 613 and will not be retained at the inner bottom of the outer shell 61.

[0032] In some embodiments of the present invention, the recycled material fine classification device 100 further includes a bag filter 91, a cyclone tower 92, an induced draft fan 93 and a chimney 94; The input end of the bag filter 91 is connected to the first air outlet 616 through an air outlet pipe 911, the output end of the bag filter 91 is connected to the input end of the cyclone tower 92, and the output end of the cyclone tower 92 is connected to the input end of the induced draft fan 93; the chimney 94 is connected to the output end of the induced draft fan 93, and the first air inlet 615 is also connected to the chimney 94 through a return air pipe 6151. When the recycled material fine grading equipment 100 of the present invention is in operation, under the action of the induced draft fan 93, the low-temperature dry air, dust and water vapor in the outer shell 61 will enter the bag dust collector 91 through the first air outlet 616 and the air outlet pipe 911 for dust removal and filtration. The low-temperature dry air and water vapor after dust removal will enter the cyclone tower 92 for dehydration. Part of the low-temperature dry air after dehydration can be discharged through the chimney 94, and the other part can be refluxed to the first air inlet 615 of the V-shaped air-drying filter 6 through the return air pipe 6151 for recycling, so as to air-dry the recycled material passing through the V-shaped air-drying filter 6.

[0033] The present invention connects the first air outlet 616 of the V-shaped air-drying filter 6 with the bag collector 91, the cyclone tower 92, the induced draft fan 93 and the chimney 94 in sequence, and connects the chimney 94 with the first air inlet 615 of the V-shaped air-drying filter 6, so that during specific operation, the bag collector 91 and the cyclone tower 92 can be used to remove dust and water vapor generated during the operation to obtain low-temperature dry air, and the treated low-temperature dry air can be transported back to the first air inlet 615 of the V-shaped air-drying filter 6 for recycling.

[0034] As a specific implementation of the present invention, please focus on Figure 6As shown, the V-shaped impact structure 62 includes two rows of wear-resistant steel plates 621 spaced from top to bottom, that is, each row includes multiple wear-resistant steel plates 621 spaced from top to bottom; a material channel 622 is left between the two rows of wear-resistant steel plates 621, so that recycled materials with a particle size of more than 2 mm can fall down through the material channel 622; the midpoints of the two rows of wear-resistant steel plates 621 are connected by two parallel oblique lines, that is, the connection between the two end points of the wear-resistant steel plates 621 in the same row is an oblique line, so that the material channel 622 formed between the two rows of wear-resistant steel plates 621 is an inclined channel; the two rows of wear-resistant steel plates 621 are staggered and distributed in a V shape, specifically, a V-shaped structure with an open middle. By adopting the design of the above-mentioned V-shaped impact structure 62 of the present invention, on the one hand, it can ensure that the recycled material with a particle size of more than 2 mm will continuously collide with the wear-resistant steel plate 621 in the process of falling down through the material channel 622, so that the recycled material can be better dispersed; on the other hand, the residence time of the recycled material in the V-shaped impact structure 62 can be increased, thereby ensuring that the low-temperature dry air can better air-dry the recycled material.

[0035] In some embodiments of the present invention, please refer to Figure 7 As shown, the feed end of the vertical shaft impact crusher 4 is provided with a second air inlet 41, and the discharge end of the vertical shaft impact crusher 4 is provided with a second air outlet 42; the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 are both provided with dust output ports (not shown); the dust output ports of the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 and the second air outlet 42 of the vertical shaft impact crusher 4 are all connected to the first air inlet 615 through an air inlet pipe 618.

[0036] The present invention provides a second air inlet 41 at the feed end of the vertical shaft impact crusher 4 and a second air outlet 42 at the discharge end of the vertical shaft impact crusher 4, so that during operation, external cold air can enter the interior of the vertical shaft impact crusher 4 through the second air inlet 41, thereby cooling the vertical shaft impact crusher 4. That is, the interior of the vertical shaft impact crusher 4 is cooled by air cooling technology, which can prevent the recycled material from sticking to the impact cavity and the rotor, and help to improve the service life; at the same time, the dust output ports of the circular vibration screen 7 and the high-frequency vibration mesh screen 8 and the second air outlet 42 of the vertical shaft impact crusher 4 are connected to the V-shaped air drying screen The first air inlet 615 of the V-type air-drying screen 6 is connected to the first air inlet 615 of the V-type air-drying screen 6. On the one hand, the dust generated by the circular vibrating screen 7, the high-frequency vibrating mesh screen 8 and the vertical shaft impact crusher 4 can be sucked into the bag dust collector 91 and the cyclone tower 92 for dust removal and water removal. On the other hand, the rotation friction of the recycled material in the vertical shaft impact crusher 4 and the relative friction during the operation of the recycled material will generate heat. After the heat is released into the air, it can be ensured that the temperature of the dry air treated by the bag dust collector 91 and the cyclone tower 92 is higher than the external ambient temperature, thereby ensuring that the low-temperature dry air transported back to the V-type air-drying screen 6 can play a role in air-drying and water-removing for the recycled material.

[0037] In some embodiments of the present invention, please refer to Figure 4 As shown, the recycled material fine classification equipment 100 also includes a feeding ring 101, a return material belt conveyor 102 and a roller crusher 103; The coarse screen 3 has a first material output end for outputting fine materials and a second material output end for outputting coarse materials. The input end of the second belt conveyor 22 is connected with the first material output end, so that the second belt conveyor 22 can convey the recycled material with a particle size less than 40 mm output from the first material output end to the vertical shaft impact crusher 4; the input end of the double-roll crusher 103 is connected with the second material output end, and the output end of the double-roll crusher 103 is connected with the input end of the feeding ring 101 through the return belt conveyor 102, and the output end of the feeding ring 101 is connected with the first belt conveyor 21. During operation, the recycled material with a particle size of more than 40 mm screened out by the coarse screen 3 will be conveyed to the double-roll crusher 103 for crushing, and returned to the first belt conveyor 21 via the return belt conveyor 102 and the feeding ring 101, so as to avoid material waste.

[0038] In some embodiments of the present invention, the circular vibrating screen 7 has a third material output end for outputting a first-grade fine material, a fourth material output end for outputting a second-grade fine material, and a fifth material output end for outputting a third-grade fine material, and the first-grade fine material is larger than the second-grade fine material, and the second-grade fine material is larger than the third-grade fine material; the fifth material output end is connected to the input end of the high-frequency vibrating mesh screen 8, and the third material output end and the fourth material output end are each connected to a fourth belt conveyor 24, that is, when the circular vibrating screen 7 is working, it will screen the recycled material input into the circular vibrating screen 7 into three grades of material, and convey the finest grade of recycled material to the high-frequency vibrating mesh screen 8 for further screening, and the other two grades of recycled material will be output through a fourth belt conveyor 24 respectively.

[0039] In some embodiments of the present invention, the high-frequency vibrating mesh screen 8 has a sixth material output end for outputting a first-grade fine material, a seventh material output end for outputting a second-grade fine material, and an eighth material output end for outputting a third-grade fine material, and the first-grade fine material is larger than the second-grade fine material, and the second-grade fine material is larger than the third-grade fine material; a collecting hopper 81 is provided below the high-frequency vibrating mesh screen 8 at a position corresponding to the eighth material output end, and the fine particle outlet 614 is connected to the collecting hopper 81; the sixth material output end, the seventh material output end and the output end of the collecting hopper 81 are each connected to a fourth belt conveyor 24, that is, when the high-frequency vibrating mesh screen 8 is in operation, it will continue to screen the recycled material input into the high-frequency vibrating mesh screen 8 into three grades of material, and mix the finest grade of recycled material with the recycled material output from the fine particle outlet 614 of the V-shaped air-drying screen 6 and output it through a fourth belt conveyor 24, and the other two grades of recycled material are also each output through a fourth belt conveyor 24.

[0040] As can be seen from the above, the recycled material fine grading equipment 100 of the present invention can achieve a total of 5 grades of recycled material output after screening by the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8, which is helpful to achieve large-scale addition application and ensure the stability of the gradation and asphalt content of the produced recycled asphalt mixture. In addition, it should be noted that the coarse grade screen 3, the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 in the present invention are all commonly used screening equipment in the field, and their specific structures and working principles are well known to those skilled in the art, so the coarse grade screen 3, the circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 will not be introduced in detail here. Embodiment 2

[0041] See also Figures 1 to 7 As shown, the present invention provides a method for finely grading recycled materials. The grading method requires the use of a finely grading device 100 for recycled materials. The specific structure and technical effects that can be obtained by the finely grading device 100 for recycled materials are exactly the same as those in the first embodiment. For details, please refer to the detailed introduction of the first embodiment, which will not be repeated here. The grading method comprises the following steps: The recycled material output from the raw material bin 1 is conveyed to the coarse screen 3 through the first belt conveyor 21, and the recycled material with a particle size less than 40 mm is screened out by the coarse screen 3 and output to the second belt conveyor 22; wherein the raw material bin 1 uses a frequency converter to control the motor speed to control the feeding amount; The regenerated material is conveyed to the vertical shaft impact crusher 4 through the second belt conveyor 22 for breaking up, so as to ensure that no false particles appear in each grade of the regenerated material after the final screening, and the broken regenerated material is conveyed to the elevator 5 through the third belt conveyor 23, and the elevator 5 lifts the regenerated material and outputs it to the V-shaped air-drying screener 6; The V-shaped air-drying screener 6 is used to air-dry, dehydrate and screen the recycled material into two grades to prevent clogging and sticking of the subsequent circular vibrating screen 7 and the high-frequency vibrating mesh screen 8 during the screening process; the recycled material with a particle size of more than 2 mm is transported to the circular vibrating screen 7 for further screening, while the recycled material with a particle size less than 2 mm does not enter the circular vibrating screen 7; the recycled material is screened into three grades by the circular vibrating screen 7, the finest grade of recycled material is transported to the high-frequency vibrating mesh screen 8 for further screening, and the remaining two grades of recycled material are each output through a fourth belt conveyor 24; the recycled material is further screened into three grades by the high-frequency vibrating mesh screen 8, the finest grade of recycled material is mixed with the recycled material with a particle size less than 2 mm output by the V-shaped air-drying screener 6 and output through a fourth belt conveyor 24, and the remaining two grades of recycled material are each output through a fourth belt conveyor 24, thereby achieving the output of 5 grades of material.

[0042] In the present invention, the classification method further comprises the following steps: The recycled materials with a particle size of more than 40 mm screened by the coarse screen 3 are conveyed to the roller crusher 103 for crushing, so as to crush the recycled materials with a particle size of more than 40 mm into smaller recycled materials, and the crushed recycled materials are conveyed to the feeding ring 101 through the return belt conveyor 102, and the crushed recycled materials are conveyed back to the first belt conveyor 21 through the feeding ring 101; The dust and water vapor output by the V-shaped air-drying filter 6 are sucked into the bag filter 91 for dust removal by the induced draft fan 93, and then enter the cyclone tower 92 for water removal; a part of the treated hot dry air is discharged through the chimney 94, and the other part of the hot dry air is transported back to the first air inlet 615 of the V-shaped air-drying filter 6 for recycling.

[0043] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A recycled material fine classification device, characterized by: It includes a raw material bin, a first belt conveyor arranged at the output end of the raw material bin, a coarse grade screen arranged at the output end of the first belt conveyor, a second belt conveyor arranged at the output end of the coarse grade screen, a vertical shaft impact crusher arranged at the output end of the second belt conveyor, a third belt conveyor arranged at the output end of the vertical shaft impact crusher, an elevator arranged at the output end of the third belt conveyor, a V-shaped air-drying screen arranged at the output end of the elevator, a circular vibrating screen connected to the output end of the V-shaped air-drying screen, a high-frequency vibrating mesh screen connected to the output end of the circular vibrating screen, and a fourth belt conveyor arranged at the output ends of the circular vibrating screen and the high-frequency vibrating mesh screen.

2. A recycled material fine classification device as claimed in claim 1, characterized in that: The V-shaped air-drying screener comprises an outer shell and a V-shaped impact structure; a screening chamber is formed in the outer shell, and the V-shaped impact structures are arranged in the screening chamber from top to bottom; a material inlet is provided at the top of the outer shell at a position corresponding to the V-shaped impact structure, and a large particle outlet is provided at the bottom of the outer shell at a position corresponding to the V-shaped impact structure; the outer shell is also provided with a fine particle outlet, a first air inlet and a first air outlet, the first air inlet is located on either side of the V-shaped impact structure, the fine particle outlet and the first air outlet are located on the other side of the V-shaped impact structure, and the fine particle outlet is provided at the bottom of the outer shell, and the first air outlet is provided at the top of the outer shell; A convex portion with a triangular cross-section is formed on the inner bottom of the outer shell between the fine particle outlet and the large particle outlet.

3. A recycled material fine classification device as claimed in claim 2, characterized in that: It also includes bag filters, cyclone towers, induced draft fans, and chimneys; The input end of the bag filter is connected to the first air outlet through an air outlet pipe, the output end of the bag filter is connected to the input end of the cyclone tower, and the output end of the cyclone tower is connected to the input end of the induced draft fan; the chimney is connected to the output end of the induced draft fan, and the first air inlet is also connected to the chimney through a return air duct.

4. A recycled material fine classification device as claimed in claim 2, characterized in that: The V-shaped impact structure includes two rows of wear-resistant steel plates spaced from top to bottom, a material channel is left between the two rows of wear-resistant steel plates, the midpoints of the two rows of wear-resistant steel plates are connected by two parallel oblique lines, and the two rows of wear-resistant steel plates are staggered and arranged in a V-shaped distribution.

5. A recycled material fine classification device as claimed in claim 2, characterized in that: The feed end of the vertical shaft impact crusher is provided with a second air inlet, and the discharge end of the vertical shaft impact crusher is provided with a second air outlet; the circular vibrating screen and the high-frequency vibrating mesh screen are both provided with dust output ports; the dust output ports of the circular vibrating screen and the high-frequency vibrating mesh screen and the second air outlet of the vertical shaft impact crusher are all connected to the first air inlet through an air inlet pipe.

6. A recycled material fine classification device as claimed in claim 1, characterized in that: It also includes a feeding ring, a return belt conveyor and a roller crusher; The coarse grade screen has a first material output end for outputting fine material and a second material output end for outputting coarse material, and the input end of the second belt conveyor is connected with the first material output end; the input end of the double-roll crusher is connected with the second material output end, and the output end of the double-roll crusher is connected with the input end of the loading ring through the return belt conveyor, and the output end of the loading ring is connected with the first belt conveyor.

7. A recycled material fine classification device as claimed in claim 1, characterized in that: The circular vibrating screen has a third material output end for outputting a first-grade fine material, a fourth material output end for outputting a second-grade fine material, and a fifth material output end for outputting a third-grade fine material, and the first-grade fine material is larger than the second-grade fine material, and the second-grade fine material is larger than the third-grade fine material; The fifth material output end is connected to the input end of the high-frequency vibrating mesh screen, and the third material output end and the fourth material output end are each connected to a fourth belt conveyor.

8. A recycled material fine classification device as claimed in claim 2, characterized in that: The high-frequency vibration screen has a sixth material output end for outputting a first-grade fine material, a seventh material output end for outputting a second-grade fine material, and an eighth material output end for outputting a third-grade fine material, and the first-grade fine material is larger than the second-grade fine material, and the second-grade fine material is larger than the third-grade fine material; A collecting hopper is provided below the high-frequency vibrating screen at a position corresponding to the eighth material output end, and the fine particle outlet is connected to the collecting hopper; the sixth material output end, the seventh material output end and the output end of the collecting hopper are each connected to a fourth belt conveyor.

9. A method for fine classification of recycled materials, characterized in that: The classification method comprises the following steps: The recycled material output from the raw material bin is conveyed to the coarse screen through the first belt conveyor, and the recycled material with a particle size less than 40 mm is screened out by the coarse screen and output to the second belt conveyor; The recycled material is conveyed to the vertical shaft impact crusher through the second belt conveyor for breaking up, and the broken recycled material is conveyed to the elevator through the third belt conveyor, and the elevator lifts the recycled material and outputs it to the V-type air-drying screener; The recycled material is air-dried, dehydrated and screened into two grades by using a V-shaped air-drying screen, and the recycled material with a particle size of more than 2 mm is conveyed to a circular vibrating screen for further screening; the recycled material is screened into three grades by the circular vibrating screen, and the finest grade of recycled material is conveyed to a high-frequency vibrating screen for further screening, and the remaining two grades of recycled material are each output through a fourth belt conveyor; the recycled material is further screened into three grades by a high-frequency vibrating screen, and the finest grade of recycled material is mixed with the recycled material with a particle size of less than 2 mm output by the V-shaped air-drying screen and output through a fourth belt conveyor, and the remaining two grades of recycled material are each output through a fourth belt conveyor.

10. A method for fine classification of recycled materials as claimed in claim 9, characterized in that: The classification method further comprises the following steps: The recycled materials with a particle size of more than 40 mm screened by the coarse screen are transported to the roller crusher for crushing, and the crushed recycled materials are transported to the feeding ring through the return belt conveyor, and the crushed recycled materials are transported back to the first belt conveyor through the feeding ring; The induced draft fan is used to draw the dust and water vapor output by the V-type air-drying filter into the bag dust collector for dust removal, and then enters the cyclone tower for water removal; a part of the treated hot dry air is discharged through the chimney, and the other part of the hot dry air is transported back to the first air inlet of the V-type air-drying filter for recycling.

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