CN120588386B - A recycling system and method for film rolls and scrap. - Google Patents

Abstract

This invention discloses a recycling system and method for film rolls and scrap. The recycling system includes an extrusion production line, a first feeding conveyor line, a second feeding conveyor line, and a cutting production line. This application can simultaneously process two types of film: sheet waste film and roll film. Roll film is wound into a cylindrical shape during recycling. To address the characteristics of sheet waste film—its looseness and tendency to accumulate and clog at low density—this application includes a first feeding conveyor line to crush the sheet waste film. Furthermore, to improve feeding efficiency, at least three extrusion inlets are provided in the extrusion production line for gradual feeding, improving extrusion plasticization stability. Roll film contains a paper core, which must be cut off and removed before crushing, a time-consuming and labor-intensive process. Therefore, a second feeding conveyor line is also provided, allowing the roll film to directly enter the extrusion production line for plasticization.

Description

Film coiled material and crushed material recovery system and method

Technical Field

The invention relates to the technical field of film recovery, in particular to a recovery system and a recovery method for film coiled materials and crushed aggregates.

Background

The existing film recovery technology has the following defects:

1. The defect of film recovery in a single screw extruder production line is that the preparation formula involves a certain complexity, and the single screw extruder has difficulty in realizing normal plasticizing effect. Because of the small internal shearing force of the extruder, the material residence time of the single screw extruder exceeds 15 minutes, so that the energy consumption is increased by 20%, and the plasticization effect in the extruder is poor.

2. The plastic film aggregate forming production line has the defects that the softening point of the film is only 70 ℃, and the adhesion force to metal after melting is strong, so that the requirement on anti-sticking measures is high when the film is broken. The pelletizing die and filters are prone to clogging, irregular pellet shape, low density, and large amounts of dust.

3. The recycling defect of the film roll is that in the plastic film, some film rolls of degraded products exist, and the inside of the film rolls contains paper cores. The film must be cut off before breaking, and the paper core is taken out, which is time-consuming and laborious.

4. The production line of the double-screw extruder is used for recovering the film defects that when a high bulk density film is processed, the feeding amount is low and the melt is insufficient by adopting a starvation type feeding technology, so that plasticization is unstable, the pressure of an extrusion die head is unstable, the size of a material strip is increased and the time is reduced, and the production process shows instability. In addition, the particle sizes produced are also inconsistent.

In conclusion, the prior art has the defects of low yield, low recovery efficiency, unstable plasticization, more manual intervention and the like.

Disclosure of Invention

The present invention is directed to a film roll and scrap recycling system and method that address one or more of the problems of the prior art, and at least provide a beneficial choice or creation.

The technical scheme adopted for solving the technical problems is as follows:

The invention provides a recovery system of film coiled material and crushed aggregates, comprising:

The extrusion production line comprises an extruder and at least three weightless feeders, wherein the extruder comprises two screws which are arranged in parallel, each screw comprises a plurality of modularized screw elements which are sequentially arranged along the conveying direction of materials, each screw element comprises at least one of conveying threads, kneading blocks and reverse threads, at least three extrusion feed inlets are sequentially arranged on a machine barrel of the extruder at intervals along the conveying direction, each extrusion feed inlet corresponds to one screw element, the weightless feeders are provided with a first feed inlet, a second feed inlet and a feed outlet, the first feed inlet and the second feed inlet are both communicated with the feed outlet, a stirring structure is arranged in a connecting channel of the first feed inlet and the feed outlet, a film guide assembly is arranged in a connecting channel of the second feed inlet and the feed outlet, and each film guide assembly comprises a film guide roller;

The first feeding conveying line comprises a feeding conveying belt, a crusher and a storage stirrer which are sequentially arranged along the conveying direction of the first feeding conveying line, so that materials are conveyed to the crusher through the feeding conveying belt and then stirred by the storage stirrer, a stirring discharge port is arranged at the bottom of the storage stirrer, and the stirring discharge port is communicated with at least three first feeding inlets;

the second feeding conveying line comprises at least three feeding assemblies which are arranged in one-to-one correspondence with at least three second feeding inlets, the feeding assemblies comprise a feeding scroll and a rotary driving unit for driving the feeding scroll to rotate, and coiled materials on the feeding scroll enter the extrusion feeding inlet through a film guide roller;

And the blanking production line is used for cooling the continuous material strips produced by the extrusion production line and taking the continuous material strips into a granulator for cutting.

The beneficial effects of the invention are as follows:

The application can process two materials of sheet waste film and coiled material film at the same time, paper core is not needed to be removed when the coiled material film is recovered, the bulk density and the feeding quantity of raw materials are improved by the weightless feeder, meanwhile, the feeding proportion of each extrusion feeding port can be flexibly adjusted by cooperatively controlling a plurality of extrusion feeding ports, the plasticizing process is optimized, and the product quality is improved. In addition, the design also reduces manual intervention, reduces operation difficulty and labor intensity, realizes automation and intellectualization of the production process, and can realize efficient plasticization and mixing of different materials based on the optimized combination design of the modularized threaded elements, thereby effectively reducing the problem of excessive or insufficient plasticization and improving the stability of product quality.

As a further improvement of the technical scheme, the second feeding conveying line further comprises an unreeling frame, a plurality of feeding grooves and at least three supporting and positioning grooves are formed in the unreeling frame, and when the material scroll is located in the supporting and positioning grooves, the material scroll is in transmission connection with the transmission end of the rotary driving unit.

As a further improvement of the technical scheme, the supporting and positioning groove comprises two supporting plates which are arranged at intervals, the supporting plates are provided with supporting grooves, two ends of the material reel are respectively arranged in the supporting grooves, the material reel is provided with a driven gear, the supporting plates are rotatably provided with a transmission shaft, the rotary driving unit is in transmission connection with the transmission shaft, and the transmission shaft is fixedly provided with a driving gear meshed with the driven gear.

As a further improvement of the technical scheme, the second feeding conveying line further comprises a feeding driving unit, and the feeding driving unit is used for driving the coiled film unreeling frame to be lifted to a preset height so as to facilitate feeding.

As a further improvement of the above technical solution, the second feeding conveyor line further includes a pushing mechanical arm for moving the coil stock located in the feeding slot to the supporting and positioning slot so that the coil stock shaft of the coil stock is meshed with the driving gear through the driven gear.

As a further improvement of the technical scheme, the screw is provided with at least six first to sixth areas sequentially arranged along the material conveying direction, and at least three extrusion feed inlets are respectively provided with a first area, a third area and a fifth area, wherein screw elements positioned in the first area, the third area and the fifth area are first conveying elements, screw elements positioned in the second area, the fourth area and the sixth area are second conveying elements, and the screw pitch of the second conveying elements is smaller than that of the first conveying elements.

As a further improvement of the above technical solution, the pitch of the screw elements between the first zone to the second zone, the third zone to the fourth zone, and the fifth zone to the sixth zone is gradually reduced.

As a further improvement of the technical scheme, the stirring structure comprises stirring blades and a blade driving piece for driving the blades to rotate.

The invention also provides a method which is applied to the recovery system of the film coiled material and the crushed aggregates of any one of the above steps of the method, and the method comprises the following steps:

preparing a sheet waste film and a coil stock film;

Crushing and stirring the sheet waste film, and then respectively conveying the crushed and stirred sheet waste film to at least three extrusion feed inlets of an extruder, wherein at least three coiled material films respectively enter at least three extrusion feed inlets of the extruder;

extruding the sheet waste film and the coil stock film through an extruder to form a continuous material strip;

Cooling and cutting the continuous strand into pellets;

sequentially spin-drying the cut particles, and screening out qualified particles;

and drying the qualified granules to obtain finished granules.

As a further improvement of the above technical solution, the at least three extrusion feed inlets for respectively conveying the sheet waste film after crushing and stirring to the extruder, and the at least three coil stock films respectively enter the at least three extrusion feed inlets further comprises:

Conveying the sheet waste film to at least three extrusion feed inlets of an extruder through at least three weightless feeders respectively, and regulating the feeding amount in real time through a PLC;

The coiled material film is unwound by a material reel driven by at least three rotary driving units, the linear speed of the coiled material film is linked with a feeding machine, and the amount of the film entering a corresponding extrusion feeding hole is controlled;

According to the melt pressure sensor and torque data of the extruder, the feeding proportion of the flaky waste film and the coiled material film is dynamically adjusted, so that the temperature fluctuation of a plasticizing section is less than or equal to +/-3 ℃.

Drawings

The invention is further described below with reference to the drawings and examples;

FIG. 1 is a schematic view of a recycling system for coiled and crushed materials of film according to an embodiment of the present invention;

FIG. 2 is a schematic top view of an embodiment of a film roll and scrap recycling system according to the present invention;

FIG. 3 is a schematic view of a first embodiment of a film roll and scrap recovery system according to the present invention;

FIG. 4 is a schematic diagram of an extrusion line according to one embodiment of the present invention for a film roll and scrap recovery system;

FIG. 5 is an enlarged view of A in FIG. 4;

FIG. 6 is a schematic view of an exemplary unreeling rack of a recycling system for film rolls and scraps according to the present invention;

FIG. 7 is a block diagram of an exemplary unwind stand of a film roll and scrap recovery system according to the present invention;

FIG. 8 is a top view of an exemplary unwind stand of a film roll and scrap recovery system according to the present invention;

FIG. 9 is a side view of an exemplary unwind stand of a film web and scrap recovery system according to the present invention;

FIG. 10 is a side view of one embodiment of a screw of the film roll and scrap recovery system provided by the present invention;

FIG. 11 is a flow chart of a method of operation of a film web and scrap recovery system according to the present invention.

Reference numerals:

a first feeding conveyor line 100, a climbing conveyor belt 110, a crusher 120, a feeding fan 130, a storage stirrer 140 and a stirring discharge port 141;

A second feeding conveyor line 200, a material reel 210, a driven gear 211, an unreeling frame 220, a feeding groove 221, a supporting positioning groove 222, a supporting plate 2221, a transmission shaft 230 and a driving gear 231;

Extrusion line 300, extruder 310, extrusion motor 311, extrusion reduction box 312, screw 313, vacuum pumping system 314, soft water internal circulation system 315, extrusion feed port 316, weightless feeder 320, first feed inlet 321, second feed inlet 322, feed outlet 323, stirring barrel 324, stirring blade 325, filter plate 326, and film guide roller 327;

The blanking production line 400, the water flushing tank 410, the high-speed water flow device 420, the granulator 430, the dehydrator 440, the vibrating screen 450, the vacuum feeder 460, the receiving hopper 470, the homogenizing drying bin 480 and the water chiller system 490.

Detailed Description

Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the accompanying drawings are used to supplement the description of the written description so that one can intuitively and intuitively understand each technical feature and overall technical scheme of the present invention, but not to limit the scope of the present invention.

In the description of the present invention, it should be understood that references to orientation descriptions such as upper, lower, front, rear, left, right, etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of description of the present invention and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention.

In the description of the present invention, if there is a word description such as "a plurality" or the like, the meaning of a plurality is one or more, and the meaning of a plurality is two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number.

In the description of the present invention, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present invention can be reasonably determined by a person skilled in the art in combination with the specific contents of the technical scheme.

Referring to fig. 1 to 11, the present invention is directed to a film roll and scrap recycling system and method, according to the following embodiments:

Referring to fig. 1, a film roll and scrap recovery system includes an extrusion line 300, a first feed conveyor line 100, a second feed conveyor line 200, and a blanking line 400.

The application can process two types of films simultaneously, one is a sheet waste film and a coiled material film, the sheet waste film is a large sheet polypropylene waste film, the coiled material film is a polypropylene film coiled material, the sheet waste film is in a flake shape when being recovered, the thickness is 0.05-2 mm, the coiled material film is coiled into a barrel shape through a winding drum when being recovered, and the application is characterized in that the sheet waste film is fluffy and easy to accumulate and block at low density. The paper core is contained in the coiled material film, the film must be cut off before being broken, and the paper core is taken out, so that the process is time-consuming and labor-consuming. A second feed conveyor line 200 is therefore also provided through which the film roll can be directly fed into the extrusion line 300 for plasticization.

The extrusion production line 300 adopts the extruder 310 with double screws 313, and improves the extruder 310, and is provided with at least three extrusion feed inlets 316, and the feeding rate of plastics is adjusted by matching the first feeding conveyor line 100 and the second feeding conveyor line 200, so that the feeding efficiency and the feeding stability are improved.

The blanking line 400 performs a cooling cutting process on the continuous strand formed by the extrusion line 300 to obtain the final product.

The extrusion production line 300 comprises an extruder 310, three weightless feeders 320 and a vacuum pumping system 314, wherein the extruder 310 comprises an extrusion motor 311, an extrusion reduction gearbox 312, two screws 313, a vacuum pumping system 314 and a soft water internal circulation system 315. The extruder 310 comprises two screws 313 arranged in parallel, each screw 313 comprises twelve modularized screw 313 elements which are sequentially arranged along the conveying direction of materials, each screw 313 element comprises at least one of conveying threads, kneading blocks and reverse threads, namely, each screw 313 is provided with a first region to a twelfth region which are sequentially provided with twelve screws along the conveying direction of materials, the length-diameter ratio reaches 48, each region corresponds to one screw 313 element, three extrusion feed inlets 316 are sequentially arranged at intervals along the conveying direction of the barrel of the extruder 310, and the three extrusion feed inlets 316 are arranged to improve the feeding amount of the extruder 310. The three extrusion feed inlets 316 are respectively provided with a first zone, a third zone and a fifth zone, wherein screw 313 elements in the first zone, the third zone and the fifth zone are first conveying elements, screw 313 elements in the second zone, the fourth zone and the sixth zone are second conveying elements, and the screw pitch of the second conveying elements is smaller than that of the first conveying elements. The pitch of the screw 313 elements between the first zone to the second zone, the third zone to the fourth zone, and the fifth zone to the sixth zone gradually decreases, gradually decreasing from 72mm to 44mm. Thus, each two zones form a set of feed zones, repeatedly compressing and melting the film. Multiple extrusion feeds 316 may increase the feed rate of the extruder 310. The screw 313 is shown in figure 10.

The remaining regions of the screw 313 include a melting section, kneading blocks (45 ° forward, high shear melting) +reverse flighting (build pressure), a vent section, shallow slot conveying flighting, enlarged surface area for vacuum devolatilization, a homogenizing section, small pitch flighting, stable extrusion pressure 0, aimed at efficient melting, filtration of impurities, devolatilization, removal of water/solvent, respectively.

The screw 313 is based on the optimal combination design of modularized threaded elements, so that efficient plasticization and mixing of different materials can be realized, the problem of excessive plasticization or insufficient plasticization is effectively reduced, and the stability of product quality is improved. The design ensures that the equipment has higher flexibility and adaptability when processing waste film raw materials with different types or different proportions, does not need to frequently replace equipment or adjust process parameters, and reduces the production cost and the operation complexity. In addition, the thread combination design is also beneficial to reducing energy consumption, improving the overall energy efficiency of equipment, and conforming to the production concept of green and environmental protection.

Referring to fig. 4 and 5, the weightless feeder 320 is provided with a first feeding inlet 321, a second feeding inlet 322 and a feeding outlet 323, the first feeding inlet 321 and the second feeding inlet 322 are all communicated with the feeding outlet 323, a stirring barrel 324 is arranged in a connecting channel of the first feeding inlet 321 and the feeding outlet 323, the stirring structure is arranged in the stirring barrel 324 and comprises stirring blades 325 and a blade driving piece for driving the blades to rotate, stirring is carried out on crushed films to prevent blockage, a filter plate 326 can be arranged at the bottom of the stirring barrel 324, the crushed films are filtered, and the stirring blades 325 have a crushing effect on the crushed films to form secondary crushing and reduce blockage.

The connecting channel of the second feeding inlet 322 and the feeding outlet 323 is provided with a film guiding component, the film guiding component comprises a film guiding roller 327 which is rotatably positioned in the connecting channel of the second feeding inlet 322 and the feeding outlet 323, the three feeding outlets 323 are arranged in one-to-one correspondence with the three extrusion feeding inlets 316, and three groups of coil stock films are respectively conveyed to the three extrusion feeding inlets 316 one by one;

The first feeding conveying line 100 comprises a feeding conveying belt, a crusher 120, a feeding fan 130 and a storage stirrer 140 which are sequentially arranged along the conveying direction of the first feeding conveying line 100, wherein a stirring discharge port 141 is formed in the bottom of the storage stirrer 140, and the stirring discharge port 141 is communicated with three first feeding inlets 321. The feeding conveyor belt in this embodiment is a climbing conveyor belt 110, the climbing conveyor belt 110 can convey the sheet waste film from the ground to the inlet of the crusher 120 from the bottom up, the sheet waste film enters the crusher 120 to be crushed under the action of gravity, and the crusher 120 breaks the sheet waste film into small fragments and then conveys the fragments into the storage stirring barrel 324 of the storage stirrer 140 through the feeding fan 130. The material in the storage agitator 324 enters the agitation outlet 141 through three sets of feeders. The particle size of the waste film fragments is controlled within 5mm through the pre-crusher 120, so that the uniformity of fragments is ensured, the blocking risk is reduced, the production efficiency is improved, and the stability and the product quality of the subsequent plasticizing process are improved. By accurately controlling the particle size of the fragments, the conveying efficiency of the feeding screw 313 can be optimized, the problem of unsmooth feeding caused by uneven particle size is reduced, and the fluency and efficiency of the whole production line are further improved.

The chopped waste film is fed into the extruder 310 through a feed screw 313 section for plasticization. The waste film and the film roll strip material can be mixed according to a certain proportion for recycling. By introducing the filter plate 326, the stirring fan blade 325 and the stirring component into the feeding device of the extruder 310, the problem of blockage caused by raw material accumulation is solved, uniform discharging and efficient filtering of raw materials are realized, and the working efficiency is improved.

The second feeding conveyor line 200 includes three feeding assemblies disposed in one-to-one correspondence with the three second feeding inlets 322, the feeding assemblies include a feeding reel 210 and a rotation driving unit for driving the feeding reel 210 to rotate, referring to fig. 6, a roll material on the feeding reel 210 enters the extrusion feeding inlet 316 through the film guiding roller 327, a roll material film drives the feeding reel 210 to rotate through the rotation driving unit and enters the extrusion feeding inlet 316 under the guidance of the film guiding roller 327, and the feeding rate of the roll material film is controlled by controlling the rotation speed and the tension of the feeding reel 210. The chopped waste film is fed into the twin screw 313 extruder 310 through the feed screw 313 for plasticization. The waste film and the film roll strip material can be mixed according to a certain proportion for recycling. The two production lines and the matching feeder and extruder 310 are arranged to ensure sufficient feeding quantity and sufficient and stable melt back pressure, and can ensure that the grain size tolerance is controlled within +/-0.2 mm to form high-stability grains, thereby meeting the standard of high-end reclaimed materials.

The blanking production line 400 comprises a water flushing tank 410, a high-speed water flow device 420, a granulator 430, a dehydrator 440, a vibrating screen 450, a vacuum feeder 460, a receiving hopper 470, a homogenizing drying bin 480 and a cold water machine system 490, wherein the high-speed water flow device 420 is used for cooling continuous strips produced by the screw 313 extrusion production line 300 and carrying the continuous strips into the granulator 430 for cutting. As the plastic melt passes through the die of extruder 310, it is formed into a continuous strand, which is rapidly passed through a high velocity water flow device 420, where the water temperature is set to 20C for instantaneous cooling to prevent melt sticking. The action of the water flow not only cools the melt, but also cuts the strand in a special pelletizer 430, the cutter rotates at high speed to sever the strand, and the particle size is cooperatively controlled by the cutter speed and extrusion speed to form uniformly sized particles. The particles then enter the spin dryer 440 with the water flow into the dewatering section where most of the water is removed. The oversized or undersized particles are then screened off by vibrating screen 450 and the acceptable particles fall into receiving hopper 470. Finally, the vacuum loading system delivers the pellets to a homogenizing dryer bin 480 where the acceptable pellets are further dried by hot air to ultimately produce finished pellets.

Further, referring to fig. 4 to 9, the second feeding conveyor line 200 further includes an unreeling frame 220, the unreeling frame 220 is provided with a plurality of feeding slots 221 and three supporting positioning slots 222, the supporting positioning slots 222 include two supporting plates 2221 arranged at intervals, the supporting plates 2221 are provided with supporting slots, and two ends of the material reel 210 are respectively arranged in the supporting slots. The material reel 210 is provided with a driven gear 211, the supporting plate 2221 is rotatably provided with a transmission shaft 230, the rotary driving unit is in transmission connection with the transmission shaft 230, and the transmission shaft 230 is fixedly provided with a driving gear 231 engaged with the driven gear 211. When the material reel 210 sleeved with the roll material film is located in the supporting and positioning groove 222, the material reel 210 is in transmission connection with the transmission end of the rotary driving unit, the rotary driving unit can drive the material reel 210 to rotate, the roll material film enters the extrusion feeding hole 316, and the feeding amount of the roll material film can be controlled by controlling the rotary driving unit. When in use, the coiled material film with paper core is sleeved on the material scroll 210, two ends of the material scroll 210 are placed in the supporting grooves, the driving gear 231 is meshed with the driven gear 211, and the material scroll 210 is driven to rotate by the rotary driving unit, so that feeding can be performed.

The feeding groove 221 can adopt a structure of the type of supporting and positioning groove 222, the feeding groove 221 is divided into three groups, the three groups are respectively arranged on the unreeling frame 220, when the last coiled material film is used up, the coiled material positioned in the feeding groove 221 is moved to the supporting and positioning groove 222 by the pushing mechanical arm, so that the coiled material shaft of the coiled material film is meshed with the driving gear 231 through the driven gear 211, and the feeding can be completed, and the automation is improved. The second feeding conveyor line 200 further includes a feeding driving unit for driving the unreeling rack 220 to rise and fall to a predetermined height so that the free end of the rolled film enters the feeding port of the twin screw 313 extruder 310. During rotation of the film roll, the film material is gradually drawn into the extruder 310 for plasticization and extrusion. By adjusting the rotation speed and the tension of the coiled material film, the feeding speed of the film material is accurately controlled, and the continuous production stability is ensured. The two ends of the material scroll 210 are placed in the material feeding groove 221, the material feeding rotating arm is driven to rotate through the material feeding cylinder, the material feeding groove 221 is lifted to a preset height, the material scroll 210 is pushed to the supporting section and then to the supporting positioning groove 222, and the material feeding is completed.

In conclusion, the invention improves the bulk density and the feeding quantity of raw materials by 500 percent through the dynamic balance of three-zone feeding, and simultaneously, the three-zone cooperative control can flexibly adjust the feeding proportion of each zone, optimize the plasticizing process and improve the product quality. In addition, the design also reduces manual intervention, reduces operation difficulty and labor intensity, and realizes automation and intellectualization of the production process.

It should be noted that the driving mechanisms of the driving units of the present utility model are all of the prior art, and the above-mentioned rotation motion, lifting motion and moving motion can all use the transmission of air cylinder, electric push rod and motor screw as the driving units. In the linear motion, corresponding sliding rails are arranged, so that the motion precision is improved, and in the rotary motion, corresponding rotary shafts are arranged, so that the rotary precision and stability can be improved.

The invention also provides an embodiment of a method, which is applied to the recovery system of the film coiled material and the crushed aggregates of any one of the above steps of the method, and the method comprises the following steps:

s100, preparing a sheet waste film and a coil stock film;

s200, crushing and stirring the sheet waste film, and then respectively conveying the crushed and stirred sheet waste film to at least three extrusion feed inlets 316 of an extruder 310, wherein at least three coiled material films respectively enter at least three extrusion feed inlets 316;

In step S200, the sheet-like waste film is first conveyed to the crusher 120 via the climbing conveyor 110, and the crusher 120 crushes the raw material into fine pieces and then conveyed to the storage agitator 3244 by the feed fan 1303. The material in the storage stirring barrel 324 enters at least three extrusion feed inlets 316 of the extruder 310 through three groups of feeders, and crushed films after the coiled material films are wrapped and crushed enter the extruder 310, so that the feeding efficiency is further improved.

S300, extruding the sheet waste film and the coil stock film through an extruder 310 to form a continuous material strip;

in step S300, the sheet-like waste film and the roll film are melted and plasticized in the screw 313 in the extruder 310, and the plastic melt is formed into a continuous strand through the die of the extruder 310.

S400, cooling and cutting the continuous material strip into particles;

In S400, as the plastic melt passes through the die to form a continuous strand, it is rapidly cooled instantaneously by a high velocity water flow device 420 (water temperature set at 20 ℃) to prevent melt blocking. The action of the water flow not only cools the melt, but also cuts the strand in a special pelletizer 430, the cutter rotates at high speed to sever the strand, and the particle size is cooperatively controlled by the cutter speed and extrusion speed to form uniformly sized particles.

S500, sequentially spin-drying the cut particles, and screening out qualified particles;

In step S500, the particles then enter the spin dryer 440 with the water flow to enter the dewatering stage, where most of the water is removed. Then, the oversized or undersized particles are screened out by vibrating screen 450, and the qualified particles fall into receiving hopper 470;

and S600, drying the qualified particles to obtain finished product particles.

Finally, the vacuum loading system 13 delivers the pellets to a homogenizing drying bin 480 where the pellets are further dried by hot air to ultimately produce finished pellets.

Further improved, step S200 further comprises:

Conveying the sheet waste film to at least three extrusion feed inlets 316 of the extruder 310 through at least three weightless feeders 320, respectively, and adjusting the feeding amount in real time through a PLC;

The material reels 210 driven by at least three rotary driving units unwind the roll material film, the linear speed of which is linked with the feeder, and control the amount of film entering the corresponding extrusion feed port 316;

According to the melt pressure sensor and torque data of the extruder 310, the feeding proportion of the flaky waste film and the coiled material film is dynamically adjusted, so that the temperature fluctuation of the plasticizing section is less than or equal to +/-3 ℃.

According to the method, the feeding mode is further optimized, so that the proportion cooperative control of multi-source materials is realized, the feeding quantity is improved, in addition, the rheological property of a melt can be optimized by independently adjusting the feeding proportion of the sheet waste film and the coiled material film, for example, 1:0.2-1:1, the plasticization unevenness caused by proportion unbalance is avoided, the sheet waste film is conveyed by a forced feeder, the coiled material film is unfolded by tension control, and the blocking of a feeding port by fluffy materials is avoided.

The recovery system for film rolls and scrap described above with reference to FIG. 1 is example 1, wherein the extruder 310 has a first zone temperature of 180 ℃, second to tenth zone temperatures of 235 ℃, eleventh to twelfth zone temperatures of 230 ℃, extruder 310 rotation speed of 200rpm, pelletizer 430 knife speed of 30HZ, chiller water temperature of 20 ℃, feed speed of 10HZ, and crusher 120 rotation speed of 800rpm.

Comparative example 1

This comparative example differs from example 1 described above in that only sheet-like waste film was fed into the extruder 310 via the first feed conveyor line 100 for recovery granulation. And only one set of feeding equipment is used.

Comparative example 2

This comparative example differs from example 1 described above in that only sheet-like waste film was fed into the extruder 310 via the first feed conveyor line 100 for recovery granulation. And only three sets of feeding equipment were used.

Comparative example 3

This comparative example differs from example 1 above in that only a coil film was used to pass through the second feed conveyor line 200 into the extruder 310 for recovery pelletization. And only one set of feeding equipment is used.

Comparative example 4

This comparative example differs from example 1 above in that only a coil film was used to pass through the second feed conveyor line 200 into the extruder 310 for recovery pelletization. And only three sets of feeding equipment were used.

The pellets prepared in example 1 and comparative examples 1 to 4 of the present application were analyzed and the results are shown in the following table 1:

from the above examples, it is understood that the present application can achieve simultaneous recovery or separate recovery of the recovered crushed material or film roll, and that the yield is improved from 51kg/h to 257kg/h yield and the uniformity of particles is good in comparison of example 1 of the present application and comparative example 1.

While the preferred embodiments of the present application have been illustrated and described, the present application is not limited to the examples, and various equivalent modifications and substitutions can be made by one skilled in the art without departing from the spirit of the present application, and these equivalent modifications and substitutions are intended to be included in the scope of the present application as defined in the appended claims.

Claims (10)

1. A film web and scrap recovery system, comprising:

The extrusion production line comprises an extruder and at least three weightless feeders, wherein the extruder comprises two screws which are arranged in parallel, each screw comprises a plurality of modularized screw elements which are sequentially arranged along the conveying direction of materials, each screw element comprises at least one of conveying threads, kneading blocks and reverse threads, at least three extrusion feed inlets are sequentially arranged on a machine barrel of the extruder at intervals along the conveying direction, each extrusion feed inlet corresponds to one screw element, each weightless feeder is provided with a first feed inlet, a second feed inlet and a feed outlet, the first feed inlet and the second feed inlet are both communicated with the feed outlet, a stirring structure is arranged in a connecting channel of the first feed inlet and the feed outlet, a film guide assembly is arranged in a connecting channel of the second feed inlet and the feed outlet, and each film guide assembly comprises a film guide roller, and at least three feed outlets are arranged in one-to-one correspondence with at least three extrusion feed inlets;

The first feeding conveying line comprises a feeding conveying belt, a crusher and a storage stirrer which are sequentially arranged along the conveying direction of the first feeding conveying line, so that materials are conveyed to the crusher through the feeding conveying belt and then stirred by the storage stirrer, a stirring discharge port is arranged at the bottom of the storage stirrer, and the stirring discharge port is communicated with at least three first feeding inlets;

The second feeding conveying line comprises at least three feeding assemblies which are arranged in one-to-one correspondence with at least three second feeding inlets, the feeding assemblies comprise a material scroll and a rotary driving unit for driving the material scroll to rotate, and coiled materials on the material scroll enter the extrusion feeding inlet through a film guide roller;

And the blanking production line is used for cooling the continuous material strips produced by the extrusion production line and taking the continuous material strips into a granulator for cutting.

2. A film roll and scrap recycling system in accordance with claim 1 wherein:

The second feeding conveying line further comprises an unreeling frame, a plurality of feeding grooves and at least three supporting and positioning grooves are formed in the unreeling frame, and when the material scroll is located in the supporting and positioning grooves, the material scroll is in transmission connection with a transmission end of the rotary driving unit.

3. A film web and scrap recovery system in accordance with claim 2 wherein:

The support positioning groove comprises two support plates arranged at intervals, the support plates are provided with support grooves, two ends of the material scroll are respectively arranged in the support grooves, the material scroll is provided with a driven gear, the support plates are rotatably provided with a transmission shaft, the rotary driving unit is in transmission connection with the transmission shaft, and the transmission shaft is fixedly provided with a driving gear meshed with the driven gear.

4. A film roll and scrap recycling system in accordance with claim 3 wherein:

The second feeding conveying line further comprises a feeding driving unit, and the feeding driving unit is used for driving the coiled film unreeling frame to be lifted to a preset height so as to facilitate feeding.

5. A film roll and scrap recycling system in accordance with claim 3 wherein:

The second feeding conveying line further comprises a pushing mechanical arm, and the pushing mechanical arm is used for moving the coiled material located in the feeding groove to the supporting and positioning groove so that a coiled material shaft of the coiled material is meshed with the driving gear through the driven gear.

6. A film roll and scrap recycling system in accordance with claim 1 wherein:

the screw is provided with at least six first to sixth areas sequentially arranged along the material conveying direction, at least three extrusion feed inlets are respectively provided with a first area, a third area and a fifth area, screw elements positioned in the first area, the third area and the fifth area are first conveying elements, screw elements positioned in the second area, the fourth area and the sixth area are second conveying elements, and the screw pitch of the second conveying elements is smaller than that of the first conveying elements.

7. A film roll and scrap recycling system in accordance with claim 6 wherein:

the pitch of the screw elements between the first zone to the second zone, the third zone to the fourth zone, and the fifth zone to the sixth zone is gradually reduced.

8. A film roll and scrap recycling system in accordance with claim 1 wherein:

The stirring structure comprises stirring blades and a blade driving piece for driving the blades to rotate.

9. A method for use in a film web and scrap recovery system according to any one of claims 1 to 8, the method comprising the steps of:

preparing a sheet waste film and a coil stock film;

Crushing and stirring the sheet waste film, and then respectively conveying the crushed and stirred sheet waste film to at least three extrusion feed inlets of an extruder, wherein at least three coiled material films respectively enter at least three extrusion feed inlets of the extruder;

extruding the sheet waste film and the coil stock film through an extruder to form a continuous material strip;

Cooling and cutting the continuous strand into pellets;

sequentially spin-drying the cut particles, and screening out qualified particles;

and drying the qualified granules to obtain finished granules.

10. A method according to claim 9, characterized in that:

the sheet waste film is crushed and stirred and then is respectively conveyed to at least three extrusion feed inlets of the extruder, and at least three coiled material films respectively enter the at least three extrusion feed inlets at the same time, and the method further comprises the following steps:

Conveying the sheet waste film to at least three extrusion feed inlets of an extruder through at least three weightless feeders respectively, and regulating the feeding amount in real time through a PLC;

The coiled material film is unwound by a material reel driven by at least three rotary driving units, the linear speed of the coiled material film is linked with a feeding machine, and the amount of the film entering a corresponding extrusion feeding hole is controlled;

According to the melt pressure sensor and torque data of the extruder, the feeding proportion of the flaky waste film and the coiled material film is dynamically adjusted, so that the temperature fluctuation of a plasticizing section is less than or equal to +/-3 ℃.