A slicing and drying system

Abstract

The present invention relates to a slicing drying system. The outlet of the bottom discharge valve of the intermediate bin for slices is connected to the slice inlet at the top of the first slice drying tower through the first pneumatic conveying pipeline. The bottom outlet of the first slice drying tower is connected to the slice inlet at the top of the second slice drying tower through the drying tower discharge valve and the second pneumatic conveying pipeline. The bottom discharge port of the second slice drying tower is connected to the main feed port of the mixed bin. The outlet of the mixed bin is connected to a vacuum packaging machine. The hot air outlets at the tops of the first and second slice drying towers are both connected to the air inlet of the dust collector through the dust removal suction air pipes. The top air outlet of the dust collector is connected to the air supplement port of the third pneumatic conveying pipeline through the return air pipeline. The feed port of the third pneumatic conveying pipeline is connected to the outlet of the slice batching valve. The inlet of the slice batching valve is connected to the outlet of the slice batching hopper. The outlet of the third pneumatic conveying pipeline is connected to the auxiliary feed port of the mixed bin. This system can enable the slices to be in full contact with the hot air flow, thoroughly remove moisture and tetrahydrofuran, and improve the product grade.

Description

Technical Field

[0001] The present invention relates to a production system for polyester chips, and in particular to a chip drying system, belonging to the technical field of polyester chip production equipment. Background Art

[0002] In the existing production line, PBS-based chips (polybutylene succinate) are usually dehydrated by a centrifuge or a vacuum rotary drum machine, which can only remove the moisture on the surface of the PBS-based chips, so that the water content of the PBS-based chips entering the intermediate silo is still relatively high. If directly packaged, it is easy to cause degradation. At the same time, a certain amount of tetrahydrofuran (THF) in the chips is gradually released after a period of time. There are batch differences between the produced materials, and uniformity cannot be achieved, affecting the use grade of the product. Summary of the Invention

[0003] The purpose of the present invention is to overcome the problems existing in the prior art and provide a chip drying system that can make the chips fully contact with the hot air flow, thoroughly remove the moisture and tetrahydrofuran in the chips, and improve the use quality of the product.

[0004] To solve the above technical problems, a chip drying system of the present invention includes a chip intermediate silo. A middle silo discharge valve is provided at the bottom of the chip intermediate silo. The outlet of the middle silo discharge valve is connected to the chip inlet at the top of the first chip drying tower through a first pneumatic conveying pipeline. The chip outlet at the bottom of the first chip drying tower is connected to the inlet of the drying tower discharge valve. The outlet of the drying tower discharge valve is connected to the chip inlet at the top of the second chip drying tower through a second pneumatic conveying pipeline. The chip outlet at the bottom of the second chip drying tower is connected to the main inlet of the mixing silo. The outlet of the mixing silo is connected to a vacuum packaging machine.

[0005] Compared with the prior art, the present invention has achieved the following beneficial effects: The PBS-based chips in the chip intermediate silo are discharged through the middle silo discharge valve, enter the first chip drying tower under the transportation of the first pneumatic conveying pipeline, and in the first chip drying tower, the chips perform heat and moisture exchange with the hot air, and the moisture and tetrahydrofuran are evaporated. The preliminarily dried chips are discharged from the drying tower discharge valve, enter the second chip drying tower under the transportation of the second pneumatic conveying pipeline, and in the second chip drying tower, the chips continue to perform heat and moisture exchange with the hot air. After the remaining moisture and tetrahydrofuran are evaporated, they enter the mixing silo for temporary storage through the main inlet, and then enter the vacuum packaging machine for packaging. Due to two-stage series evaporation, the moisture and tetrahydrofuran in the PBS-based chips are removed, and vacuum packaging is adopted, so that degradation will not occur after being placed for a period of time, and the quality of the product is improved by one grade, meeting the use requirements of food grade.

[0006] As an improvement of the present invention, the tower hot air outlets at the tops of the first slice drying tower and the second slice drying tower are both connected to the air inlet of the dust collector through dust removal suction pipes. The top air outlet of the dust collector is connected to the air supply make-up port of the third air conveying pipe through a return air pipe. The feed inlet of the third air conveying pipe is connected to the outlet of the slice batching valve. The inlet of the slice batching valve is connected to the outlet of the slice batching hopper. The outlet of the third air conveying pipe is connected to the auxiliary feed inlet of the mixed material bin. The moisture-absorbed hot air is discharged from the tower hot air outlets at the tops of the first slice drying tower and the second slice drying tower respectively, enters the dust collector through the dust removal suction pipes. The dust in the slices is intercepted by the dust collector, and the clean tail gas enters the air supply make-up port of the third air conveying pipe through the return air pipe for recycling. Slices with different molecular weights have different viscosities. The auxiliary materials are temporarily stored in the slice batching hopper, discharged from the slice batching valve, and enter the mixed material bin from the auxiliary feed inlet under the conveying of the third air conveying pipe, and are evenly mixed with the just-dried slices entering from the main feed inlet in proportion. By changing the mixing ratio, melts with different viscosities can be obtained when the mixed slices are extruded, and the application range of the product is wider. At the same time, the waste heat and nitrogen in the clean tail gas are recovered, greatly reducing the consumption of heat energy and materials.

[0007] As a further improvement of the present invention, a drying tower Y-shaped tee is installed at the slice discharge outlet at the bottom of the second slice drying tower. The two outlets of the drying tower Y-shaped tee are respectively connected to the main feed inlets of the two mixed material bins. The outlets of the third air conveying pipe are respectively connected to the auxiliary feed inlets of the two mixed material bins. At the bottom outlets of the two mixed material bins, mixed material bin Y-shaped tees are respectively installed. The outlets of the mixed material bin Y-shaped tees are respectively connected to the feed inlets of the first vacuum packaging machine and the second vacuum packaging machine. The second slice drying tower can arbitrarily select a mixed material bin through the drying tower Y-shaped tee. Different mixing ratios can be adopted for the two mixed material bins. The bottoms of the two mixed material bins can respectively select to be docked with the first vacuum packaging machine or the second vacuum packaging machine through the mixed material bin Y-shaped tees. The first vacuum packaging machine can be a ton packaging machine, and the second vacuum packaging machine can be a 25 kg packaging machine to meet the viscosity requirements and large and small packaging requirements of different customers.

[0008] As a further improvement of the present invention, the main feed inlet is located at the top center of the mixing bin, the auxiliary feed inlets are symmetrically located on both sides of the main feed inlet, and at least three mixing chutes are provided in the inner cavity of the mixing bin. Each mixing chute extends vertically and is symmetrically distributed around the axis of the mixing bin. The lower ends of the mixing chutes bend towards the conical hopper at the bottom of the mixing bin. A plurality of material discharging sections are evenly provided along the height direction of each mixing chute, and each material discharging section is provided with a material discharging port. Each material discharging port is spirally distributed along the circumference of the mixing chute. The main feed inlet and the auxiliary feed inlets feed materials simultaneously and both fall above the material layer, realizing static mixing of each section in the mixing bin. The slices in the central area of the mixing bin flow out from the bottom outlet of the mixing bin in sequence and achieve first-in, first-out; some slices in the peripheral area of the mixing bin enter the inner cavity of the mixing chute from each material discharging port, quickly descend along the mixing chute and fall into the conical hopper of the mixing bin, realizing last-in, first-out of some slices, and realizing dynamic mixing in the height direction of the mixing bin. The combined action of the first-in, first-out static mixing and the last-in, first-out dynamic mixing enables the slices discharged from the slice drying tower and the slice batching hopper to be evenly mixed in the mixing bin, greatly improving the uniformity and quality of the mixed slices. The mixing chutes are symmetrically distributed around the center, and the material discharging ports on the mixing chutes are evenly distributed in both the height direction and the circumferential direction, which can further improve the uniformity of slice mixing.

[0009] As a further improvement of the present invention, the first slice drying tower and the second slice drying tower respectively include a vertical cylindrical tower body. The slice feed inlet is provided at the top center of the tower body, and the hot air outlet of the tower body is located on one side of the slice feed inlet; the hot air inlet of the tower body is provided at the lower part of the tower body, and the bottom of the tower body is connected with a drying tower conical hopper. The slice discharging port is located at the lower end of the drying tower conical hopper. A plurality of conical baffle caps are provided along the axis of the tower body. Except for the top-layer baffle cap, baffles coaxial with it are respectively provided above each baffle cap and below the bottom-layer baffle cap. Each baffle is in the shape of a flared mouth with a larger upper part and a smaller lower part. PBS-type slices enter the inner cavity of the tower body from the slice feed inlet at the top, first fall on the outer conical surface of the top-layer baffle cap, splash and evenly scatter around, then fall downward on the inner conical surface of the baffle, splash towards the center again and fall through the central hole of the baffle and fall on the outer conical surface of the next-layer baffle cap; hot nitrogen or hot air enters from the lower part of the tower body and heats the PBS-type slices during the reverse flow upward with them. In this way, during the multiple back-and-forth downward flights of the PBS-type slices, moisture or THF is gradually removed. Finally, the slices fall into the drying tower conical hopper and are discharged from the slice discharging port at its bottom, and the hot air is discharged from the hot air outlet of the tower body at the top of the tower.

[0010] As a further improvement of the present invention, the upper ends of the baffle plates are respectively connected to the inner wall of the tower body. Each baffle plate is a thin-walled cavity structure. The lower walls of the baffle plates are respectively connected to the corresponding baffle plate air supply ring pipes through a plurality of uniformly distributed radial connecting pipes. Each baffle plate air supply ring pipe surrounds the outer periphery of the tower body and is respectively provided with a baffle plate hot air interface. A plurality of baffle plate hot air holes are uniformly distributed on the upper walls of the baffle plates. Hot nitrogen or hot air enters the inner cavities of the baffle plates along the respective radial connecting pipes from the baffle plate air supply ring pipes and sprays upward from the baffle plate hot air holes on the upper walls of the baffle plates. When the slices fall on the baffle plates, they are dried and agitated by the hot air sprayed from the baffle plate hot air holes, further improving the drying effect and uniformity.

[0011] As a further improvement of the present invention, a nitrogen or compressed air pipe is connected to the air inlet of the gas heater. The air outlet of the gas heater is connected to the hot air main pipe. The hot air main pipe is respectively connected to the hot air branch pipes of each layer. The hot air branch pipes of each layer and the cold air branch pipes of the same layer are jointly connected to the baffle plate air supply pipe of this layer. The outlets of the baffle plate air supply pipes of each layer are respectively connected to the baffle plate hot air interfaces of this layer; a hot air temperature sensor is installed on the hot air main pipe. The hot side inlet of the gas heater is connected to the steam pipe through a heat supply regulating valve, and the hot side outlet of the gas heater is connected to the condensate pipe. The opening degree of the heat supply regulating valve is controlled by the temperature measured by the hot air temperature sensor; baffle plate air supply temperature sensors are respectively installed on the baffle plate air supply pipes of each layer, and cold air regulating valves are respectively installed on the cold air branch pipes of each layer. The opening degrees of the cold air regulating valves are respectively controlled by the temperatures measured by the baffle plate air supply temperature sensors of the same layer. After nitrogen or compressed air is heated by the gas heater, it enters the hot air main pipe, and the temperature is measured by the hot air temperature sensor. If the temperature of the hot air is too low, the opening degree of the heat supply regulating valve is increased; if the temperature of the hot air is too high, the opening degree of the heat supply regulating valve is decreased. Then the hot air enters the hot air branch pipes of each layer, mixes with the cold air from the cold air branch pipes of the same layer, enters the baffle plate air supply pipe of this layer, and then enters the baffle plate of this layer through the baffle plate air supply ring pipe. When the temperature detected by the baffle plate air supply temperature sensor of a certain layer is too low, the cold air regulating valve of this layer is closed; otherwise, the cold air regulating valve of this layer is opened. In this way, through a multi-layer and independent temperature control system, different temperatures are controlled in stages according to the control process requirements of the drying tower to achieve efficient removal of moisture and tetrahydrofuran.

[0012] As a further improvement of the present invention, the upper end diameter of the drying tower conical hopper is larger than the diameter of the tower body, and the lower end of the tower body is inserted into the upper port of the drying tower conical hopper. An annular cover is provided at the upper port of the drying tower conical hopper, and the inner edge of the annular cover is welded to the outer wall of the tower body; the annular cavity below the annular cover is connected to the tower body air supply ring pipe through a plurality of evenly distributed radial connecting pipes. The tower body hot air inlet is provided on the circumference of the tower body air supply ring pipe. An annular hot air channel with a downward opening is provided between the lower port of the tower body and the inner wall of the drying tower conical hopper. Hot air enters the annular cavity at the upper end of the drying tower conical hopper from the tower body air supply ring pipe along each radial connecting pipe, and blows downward from the annular hot air channel between the tower body and the drying tower conical hopper, flowing first downward along the circumferential wall and then upward along the central area in the drying tower conical hopper, heating the slices falling into the drying tower conical hopper and making them loose, preventing sticking to the wall and mutual adhesion resulting in blockage, etc.

[0013] As a further improvement of the present invention, a stirring rotor is provided at the lower part of the drying tower conical hopper. The stirring rotor includes a stirring shaft and a plurality of stirring disk blades fixed on the stirring shaft. Both ends of the stirring shaft are supported on the drying tower conical hopper through bearing seats and are sealed with the drying tower conical hopper wall. The diameter of the stirring disk blades gradually decreases from the middle section of the stirring shaft to both ends. The stirring shaft drives each stirring disk blade to rotate, stirring the slices falling into the drying tower conical hopper to keep them in a loose state and prevent adhesion and blockage. The diameters of the stirring disk blades are distributed in a stepped manner, which can better fit the shape of the drying tower conical hopper and stir the slices more thoroughly.

[0014] As a further improvement of the present invention, a discharge cone is nested at the lower end of the drying tower conical hopper. The upper port of the discharge cone is closed and nested on the outer periphery of the lower end of the drying tower conical hopper. The annular cavity on the outer periphery of the lower end of the drying tower conical hopper is connected to the discharge cone air supply ring pipe through a plurality of evenly distributed radial connecting pipes. The discharge cone hot air interface is provided on the circumference of the discharge cone air supply ring pipe. An annular hot air channel with a downward opening is provided between the lower port of the drying tower conical hopper and the inner wall of the discharge cone. The slice discharge port is located at the lower end of the discharge cone. Hot air enters the annular cavity at the connection part between the drying tower conical hopper and the discharge cone from the discharge cone air supply ring pipe along each radial connecting pipe, and blows downward from the annular hot air channel between the drying tower conical hopper and the discharge cone, flowing first downward along the circumferential wall and then upward along the central area and blowing towards the stirring rotor in the discharge cone. On the one hand, it further heats the slices falling into the discharge cone, and on the other hand, it makes the slices tumble and loose, preventing sticking to the wall and mutual adhesion resulting in blockage, etc.

[0015] As a further improvement of the present invention, a manhole communicating with the inner cavity is provided on the circumferential wall of the discharge cone, and manholes are respectively provided on the circumferences of the upper and middle parts of the tower body. If blockage still occurs at the slice discharge port, the manhole can be opened, and the material can be conveniently removed from the manhole to make the equipment unblocked, avoiding pipeline disassembly, or entering from the manhole above for sectional cleaning or maintenance, reducing the parking treatment time.

[0016] As a further improvement of the present invention, a plurality of tower body temperature measurement interfaces are provided on the tower body along the height direction, and drying tower temperature transmitters are respectively installed in each tower body temperature measurement interface; a plurality of level gauge interfaces are provided on the tower body along the height direction, and level alarms are respectively installed in each level gauge interface. The drying tower temperature transmitter can measure the temperature of different cylinder sections in the tower body in real time, so as to control the air supply temperature entering different baffle plates. The level alarms are set in stages, and when an abnormality occurs, different treatment plans can be adopted according to the level condition.

[0017] As a further improvement of the present invention, each baffle plate is respectively spliced by a plurality of fan-shaped plates distributed in an annular array, the splicing seams of adjacent two layers of baffle plates are staggered from each other, and the angle between the baffle plate and the axis of the tower body is smaller the closer to the bottom of the tower body. The angle between each layer of baffle plate and the vertical wall of the tower body can be adjusted to control the descending speed of the slices. By adjusting the angle of the baffle plate, the residence time of the slices in each section of the tower body can be controlled to adapt to slices of different properties and particle sizes, ensuring more efficient removal of moisture and tetrahydrofuran in the slices. When the slices just enter the drying tower, the water content is relatively high, and the baffle plates are set relatively flat to extend the contact time with the hot air and increase the evaporation amount; the slices reaching the lower part of the tower body are basically dry, and the evaporation amount is small, and the baffle plates are set relatively steep to increase the descending speed of the slices. In the tower body, the phenomenon that the descending speed of the slices in the upper part is slow and the descending speed of the slices in the lower part is fast appears, greatly reducing the possibility of blockage in the tower. The splicing seams of adjacent two layers of baffle plates are staggered from each other, and a small amount of slices falling from the splicing seams will all fall on the next layer of baffle plates, avoiding the long-height falling short circuit of the slices. Description of the Drawings

[0018] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments. The drawings are only for reference and illustration, and are not intended to limit the present invention.

[0019] Figure 1 It is a flow chart of the slice drying system of the present invention.

[0020] Figure 2 It is a front view of the slice drying tower one or slice drying tower two of the present invention.

[0021] Figure 3 is Figure 2 top view.

[0022] Figure 4 For Figure 2 The top view of the first embodiment of the middle baffle plate.

[0023] Figure 5 For Figure 2 The top view of the second embodiment of the middle baffle plate.

[0024] Figure 6 The cross-sectional view of the mixture bin in the present invention.

[0025] In the figure: 1. Intermediate bin for slices; 1a. Discharge valve of the intermediate bin; 2-1. First slice drying tower; 2-2. Second slice drying tower; 2a. Slice inlet; 2b. Hot air outlet of the tower body; 2c. Pressure measuring port; 2d. Temperature measuring interface of the tower body; 2e. Sight glass; 2f. Spare port; 2g. Reserved valve port; 2h. Manhole; 2j. Interface for level gauge; 2k. Distributing umbrella cap; 2m. Baffle plate; 2m1. Hot air holes on the baffle plate; 2n. Conical hopper of the drying tower; 2n1. Stirring shaft; 2n2. Stirring disk; 2p. Discharge cone; 2p1. Slice discharge port; 2p2. Handhole; 2q. Air supply ring pipe for the baffle plate; 2r. Air supply ring pipe for the tower body; 2r1. Hot air interface for the baffle plate; 2s. Air supply ring pipe for the discharge cone; 3. Discharge valve of the drying tower; 4. Y-shaped tee of the drying tower; 5. Slice batching hopper; 5a. Slice batching valve; 6. Mixture bin; 6a. Main inlet; 6b. Auxiliary inlet; 6c. Mixing chute; 6c1. Chute outlet; 6d. Y-shaped tee of the mixture bin; 7-1. First vacuum packaging machine; 7-2. Second vacuum packaging machine; 8. Dust collector; 9. Gas heater; G1. First pneumatic conveying pipeline; G2. Second pneumatic conveying pipeline; G3. Third pneumatic conveying pipeline; G4. Dust suction pipe for dust collection; G5. Return air pipeline; G6. Nitrogen or compressed air pipe; G7. Main hot air pipeline; G8. Cold air branch pipe; G9. Steam pipe; G10. Condensate pipe; V1. Heating regulating valve; V2. Cold air regulating valve; T1. Hot air temperature sensor; T2. Air supply temperature sensor for the baffle plate. Detailed implementation manners

[0026] As Figure 1 shown, the slice drying system of the present invention includes an intermediate bin for slices 1, a first slice drying tower 2-1, a second slice drying tower 2-2 and a mixture bin 6. A discharge valve 1a of the intermediate bin is provided at the bottom of the intermediate bin for slices 1. The outlet of the discharge valve 1a of the intermediate bin is connected to the slice inlet 2a at the top of the first slice drying tower 2-1 through the first pneumatic conveying pipeline G1. The slice discharge port 2p1 at the bottom of the first slice drying tower 2-1 is connected to the inlet of the discharge valve 3 of the drying tower. The outlet of the discharge valve 3 of the drying tower is connected to the slice inlet 2a at the top of the second slice drying tower 2-2 through the second pneumatic conveying pipeline G2. The slice discharge port 2p1 at the bottom of the second slice drying tower 2-2 is connected to the main inlet 6a of the mixture bin 6. The outlet of the mixture bin 6 is connected to a vacuum packaging machine.

[0027] Combined Figure 1 、 Figure 2 As shown, the PBS-type slices in the intermediate bin 1 of the slices are discharged through the discharge valve 1a of the intermediate bin, and enter the first slice drying tower 2-1 under the transportation of the first pneumatic conveying pipeline G1. In the first slice drying tower 2-1, the slices conduct heat and moisture exchange with the hot air, and the moisture and tetrahydrofuran are evaporated. The preliminarily dried slices are discharged from the drying tower discharge valve 3, and enter the second slice drying tower 2-2 under the transportation of the second pneumatic conveying pipeline G2. In the second slice drying tower 2-2, the slices continue to conduct heat and moisture exchange with the hot air. After the remaining moisture and tetrahydrofuran are evaporated, they enter the mixing bin 6 for temporary storage through the main feed port 6a, and then enter the vacuum packaging machine for packaging. Due to two-stage series evaporation, the moisture and tetrahydrofuran in the PBS-type slices are removed, and vacuum packaging is adopted, so that degradation will not occur after being placed for a period of time, and the quality of the product is improved by one grade, and it can meet the food-grade use requirements.

[0028] The tower body hot air outlets 2b at the tops of the first slice drying tower 2-1 and the second slice drying tower 2-2 are both connected to the air inlet of the dust collector 8 through the dust removal suction air pipe G4. The top air outlet of the dust collector 8 is connected to the air supply supplement port of the third pneumatic conveying pipeline G3 through the return air pipeline G5. The feed port of the third pneumatic conveying pipeline G3 is connected to the outlet of the slice batching valve 5a, the inlet of the slice batching valve 5a is connected to the outlet of the slice batching hopper 5, and the outlet of the third pneumatic conveying pipeline G3 is connected to the auxiliary feed port 6b of the mixing bin 6. The moisture-absorbed hot air is discharged from the tower body hot air outlets 2b at the tops of the first slice drying tower 2-1 and the second slice drying tower 2-2 respectively, enters the dust collector 8 through the dust removal suction air pipe G4, the dust in the slices is intercepted by the dust collector 8, and the clean tail gas enters the air supply supplement port of the third pneumatic conveying pipeline G3 through the return air pipeline G5 for recycling. Slices with different molecular weights have different viscosities. They are proportioned and temporarily stored in the slice batching hopper 5, discharged from the slice batching valve 5a, and enter the mixing bin 6 from the auxiliary feed port 6b under the transportation of the third pneumatic conveying pipeline G3, and are uniformly mixed with the just-dried slices entering from the main feed port 6a in proportion. By changing the mixing ratio, melts with different viscosities can be obtained when the mixed slices are extruded, the application range of the product is wider, and at the same time, the waste heat and nitrogen in the clean tail gas are recovered, greatly reducing the consumption of heat energy and substances.

[0029] Such as Figure 6 As shown, the main feed port 6a is located at the top center of the mixing bin 6, the auxiliary feed ports 6b are symmetrically located on both sides of the main feed port 6a, at least three mixing chutes 6c are provided in the inner cavity of the mixing bin 6, each mixing chute 6c extends vertically and is symmetrically distributed with the axis of the mixing bin as the center, the lower ends of each mixing chute 6c bend towards the conical hopper at the bottom of the mixing bin 6, a plurality of feeding cross-sections are uniformly provided along the height direction of each mixing chute 6c, each feeding cross-section is provided with a feeding port 6c1, and each feeding port 6c1 is spirally distributed along the circumference of the mixing chute 6c.

[0030] The main feed inlet 6a and the auxiliary feed inlet 6b feed materials simultaneously and both fall above the material layer, realizing static mixing of materials at each cross-section of the mixing bin 6. The slices in the central area of the mixing bin 6 flow out from the bottom outlet of the mixing bin 6 in sequence and achieve first-in-first-out; some slices in the peripheral area of the mixing bin 6 enter the inner cavity of the mixing chute 6c from each material chute 6c1, quickly descend along the mixing chute 6c and fall into the conical hopper of the mixing bin 6, realizing last-in-first-out of some slices, and realizing dynamic mixing in the height direction of the mixing bin 6. The combined action of the first-in-first-out static mixing and the last-in-first-out dynamic mixing enables the slices discharged from the slice drying tower and the slice batching hopper 5 to be evenly mixed in the mixing bin 6, greatly improving the uniformity and quality of the mixed slices. Each mixing chute 6c is symmetrically distributed around the center, and the material chutes 6c1 on the mixing chute 6c are evenly distributed in both the height direction and the circumferential direction, which can further improve the uniformity of slice mixing.

[0031] As Figure 1 , Figure 2 shown, a drying tower Y-shaped tee 4 is installed at the slice discharge port 2p1 at the bottom of the second slice drying tower 2-2. The two outlets of the drying tower Y-shaped tee 4 are respectively connected to the main feed inlets 6a of the two mixing bins 6, and the outlets of the third pneumatic conveying pipeline G3 are respectively connected to the auxiliary feed inlets 6b of the two mixing bins 6; the bottom outlets of the two mixing bins 6 are respectively installed with mixing bin Y-shaped tees 6d, and the outlets of the mixing bin Y-shaped tees 6d are respectively connected to the feed inlets of the first vacuum packaging machine 7-1 and the second vacuum packaging machine 7-2. The second slice drying tower 2-2 can arbitrarily select the mixing bin 6 through the drying tower Y-shaped tee 4. The two mixing bins 6 can adopt different mixing ratios. The bottoms of the two mixing bins 6 can respectively select to be docked with the first vacuum packaging machine 7-1 or the second vacuum packaging machine 7-2 through the mixing bin Y-shaped tees 6d. The first vacuum packaging machine 7-1 can be a ton packaging machine, and the second vacuum packaging machine 7-2 can be a 25 kg packaging machine to meet the viscosity requirements and large and small packaging requirements of different customers.

[0032] As Figures 2 to 4 shown, the first slice drying tower 2-1 and the second slice drying tower 2-2 respectively include a vertical cylindrical tower body. A slice feed inlet 2a is provided at the center of the top of the tower body, and a tower body hot air outlet 2b is located on one side of the slice feed inlet 2a; a tower body hot air inlet is provided at the lower part of the tower body, and a drying tower conical hopper 2n is connected to the bottom of the tower body. The slice discharge port 2p1 is located at the lower end of the drying tower conical hopper 2n. A plurality of positive conical distribution umbrellas 2k are arranged along the axis of the tower body. Except for the top layer distribution umbrella 2k, baffle plates 2m coaxial with them are respectively provided above each distribution umbrella 2k and below the bottom layer distribution umbrella 2k. Each baffle plate 2m is in the shape of a flared mouth with a larger upper part and a smaller lower part.

[0033] PBS - type slices enter the inner cavity of the tower from the slice feeding port 2a at the top. First, they fall on the outer conical surface of the top - layer distribution umbrella cap 2k, splash and then scatter evenly in all directions. Then they fall downward on the inner conical surface of the baffle 2m, splash towards the center again and fall through the central hole of the baffle 2m and land on the outer conical surface of the lower - layer distribution umbrella cap 2k. Hot nitrogen or hot air enters from the lower part of the tower and heats the PBS - type slices during the upward counter - flow process with them. In this way, during the multiple back - and - forth downward flight processes of the PBS - type slices, moisture or THF is gradually removed. Finally, the slices fall into the drying tower hopper 2n and are discharged from the slice discharge port 2p1 at its bottom, and the hot air is discharged from the hot air outlet 2b at the top of the tower.

[0034] The upper ends of each baffle 2m are respectively connected to the inner wall of the tower. Each baffle 2m is a thin - wall cavity structure. The lower walls of each baffle 2m are respectively connected to the corresponding baffle air - supply ring pipe 2q through multiple evenly - distributed radial connecting pipes. Each baffle air - supply ring pipe 2q surrounds the outer periphery of the tower and is respectively provided with a baffle hot - air interface 2r1. Multiple baffle hot - air holes 2m1 are evenly distributed on the upper wall of each baffle 2m. Hot nitrogen or hot air enters the inner cavity of each baffle 2m from the baffle air - supply ring pipe 2q along each radial connecting pipe and sprays upward from each baffle hot - air hole 2m1 on the upper wall of the baffle 2m. When the slices fall on the baffle 2m, they are dried and agitated by the hot air sprayed from the baffle hot - air holes 2m1, further improving the drying effect and uniformity.

[0035] Furthermore, as Figure 1 shown, the nitrogen or compressed - air pipe G6 is connected to the air inlet of the gas heater 9. The air outlet of the gas heater 9 is connected to the hot - air main pipe G7. The hot - air main pipe G7 is respectively connected to the hot - air branch pipes of each layer. The hot - air branch pipes of each layer and the cold - air branch pipe G8 of the same layer are jointly connected to the baffle air - supply pipe of this layer. The outlets of the baffle air - supply pipes of each layer are respectively connected to the baffle hot - air interfaces 2r1 of this layer; a hot - air temperature sensor T1 is installed on the hot - air main pipe G7. The hot - side inlet of the gas heater 9 is connected to the steam pipe G9 through the heat - supply regulating valve V1. The hot - side outlet of the gas heater 9 is connected to the condensate pipe G10. The opening of the heat - supply regulating valve V1 is controlled by the temperature measured by the hot - air temperature sensor T1; baffle air - supply temperature sensors T2 are respectively installed on the baffle air - supply pipes of each layer, and cold - air regulating valves V2 are respectively installed on the cold - air branch pipes G8 of each layer. The opening of each cold - air regulating valve V2 is respectively controlled by the temperature measured by the baffle air - supply temperature sensor T2 of the same layer.

[0036] After nitrogen or compressed air is heated by the gas heater 9, it enters the hot air main pipe G7, and the temperature is measured by the hot air temperature sensor T1. If the temperature of the hot air is too low, the opening of the heat supply regulating valve V1 is increased; if the temperature of the hot air is too high, the opening of the heat supply regulating valve V1 is decreased. Then the hot air enters the hot air branch pipes of each layer, mixes with the cold air from the cold air branch pipe G8 of the same layer, enters the baffle air supply pipe of this layer, and then enters the baffle 2m of this layer through the baffle air supply annular pipe 2q. When the temperature detected by the baffle air supply temperature sensor T2 of a certain layer is too low, the cold air regulating valve V2 of this layer is closed; otherwise, the cold air regulating valve V2 of this layer is opened. In this way, through multiple layers of independent temperature control systems, different temperatures are controlled in stages according to the control process requirements of the drying tower to achieve efficient removal of moisture and tetrahydrofuran.

[0037] As Figure 2 shown, the upper end diameter of the drying tower conical hopper 2n is larger than the diameter of the tower body, and the lower end of the tower body is inserted into the upper port of the drying tower conical hopper 2n. The upper port of the drying tower conical hopper 2n is provided with an annular cover, and the inner edge of the annular cover is welded to the outer wall of the tower body; the annular cavity below the annular cover is connected to the tower body air supply annular pipe 2r through multiple evenly distributed radial connecting pipes. The circumference of the tower body air supply annular pipe 2r is provided with a tower body hot air inlet, and an annular hot air channel with a downward opening is provided between the lower port of the tower body and the inner wall of the drying tower conical hopper 2n. Four or six radial connecting pipes are evenly distributed on the same circumference to ensure uniform air distribution of the hot air on the circumference of the tower body and ensure uniform heating of the slices on the same cross-section. The hot air enters the annular cavity at the upper end of the drying tower conical hopper 2n along each radial connecting pipe from the tower body air supply annular pipe 2r, and blows downward from the annular hot air channel between the tower body and the drying tower conical hopper 2n, flowing downward along the circumferential wall first and then upward along the central area in the drying tower conical hopper 2n, heating the slices falling into the drying tower conical hopper 2n and making them loose to prevent sticking to the wall and mutual adhesion resulting in blockage, etc.

[0038] A stirring rotor is provided at the lower part of the drying tower conical hopper 2n. The stirring rotor includes a stirring shaft 2n1 and a plurality of stirring disk plates 2n2 fixed on the stirring shaft 2n1. Both ends of the stirring shaft 2n1 are supported on the drying tower conical hopper 2n through bearing seats and are sealed with the drying tower conical hopper wall. The diameter of the stirring disk plates 2n2 gradually decreases from the middle section of the stirring shaft 2n1 to both ends. The stirring shaft drives each stirring disk plate 2n2 to rotate, stirring the slices falling into the drying tower conical hopper 2n to keep them in a loose state and prevent adhesion and blockage. The diameters of the stirring disk plates 2n2 are distributed in a stepped shape, which can better fit the shape of the drying tower conical hopper 2n and stir the slices more thoroughly.

[0039] The lower end of the drying tower conical hopper 2n is nested with a discharge cone 2p. The upper port of the discharge cone 2p is closed and nested on the outer periphery of the lower end of the drying tower conical hopper 2n. The annular cavity on the outer periphery of the lower end of the drying tower conical hopper 2n is connected to the discharge cone air supply ring pipe 2s through multiple uniformly distributed radial connecting pipes. The circumference of the discharge cone air supply ring pipe 2s is provided with a hot air interface for the discharge cone. An annular hot air channel with a downward opening is provided between the lower port of the drying tower conical hopper 2n and the inner wall of the discharge cone 2p. The slice discharge port 2p1 is located at the lower end of the discharge cone 2p. Hot air enters the annular cavity at the connection part between the drying tower conical hopper 2n and the discharge cone 2p along each radial connecting pipe from the discharge cone air supply ring pipe 2s, and blows downward from the annular hot air channel between the drying tower conical hopper 2n and the discharge cone 2p, and blows out in the discharge cone 2p first downward along the circumferential wall and then upward to the stirring rotor in the central area. On the one hand, it further heats the slices falling into the discharge cone 2p, and on the other hand, it makes the slices tumble and loosen, preventing sticking to the wall and mutual adhesion from causing blockage, etc.

[0040] A manhole 2p2 communicating with the inner cavity is provided on the circumferential wall of the discharge cone 2p, and manholes are respectively provided on the circumferences of the upper and middle parts of the tower body. If blockage still occurs at the slice discharge port 2p1, the manhole 2p2 can be opened, and the material can be conveniently removed from the manhole 2p2 to make the equipment unblocked, avoiding pipeline disassembly, or entering from the manhole above for sectional cleaning or maintenance, reducing the shutdown handling time.

[0041] As Figure 2 、 Figure 3 As shown, a pressure measuring port 2c, a tower body temperature measuring interface 2d, a sight glass 2e, a spare port 2f, and a reserved valve port 2g are further provided on the top head of the tower body, and manholes 2h are respectively provided on the circumferences of the upper and middle parts of the tower body. The inner cavity of the tower body can be pressure measured through the pressure measuring port 2c, the flow state of the slices in the tower body can be observed through the sight glass 2e, and the inner cavity of the tower body can be entered from the manhole 2h for sectional cleaning or maintenance.

[0042] The tower body is provided with multiple tower body temperature measuring interfaces along the height direction, and drying tower temperature transmitters are respectively installed in each tower body temperature measuring interface; the tower body is provided with multiple level gauge interfaces 2j along the height direction, and level alarms are respectively installed in each level gauge interface 2j. The drying tower temperature transmitter can measure the temperature of different cylinder sections in the tower body in real time, so as to control the air supply temperature entering different baffle plates 2m. The level alarms are set in stages, and when abnormalities occur, different treatment plans can be adopted according to the level conditions.

[0043] Furthermore, as Figure 5As shown, each baffle plate 2m is respectively formed by splicing a plurality of sector plates distributed in an annular array. The splicing seams of adjacent two layers of baffle plates 2m are staggered from each other, and the angle between the baffle plate 2m and the tower axis is smaller closer to the bottom of the tower body. The angle between each layer of baffle plate 2m and the vertical wall of the tower body can be adjusted to control the descending speed of the slices. By adjusting the angle of the baffle plate 2m, the residence time of the slices in each section of the tower body can be controlled to adapt to slices of different properties and particle sizes, ensuring more efficient removal of water and tetrahydrofuran in the slices. The slices just entering the drying tower have a relatively high water content, and the baffle plate 2m is set relatively flat to extend the contact time with the hot air and increase the evaporation amount; the slices reaching the lower part of the tower body are basically dry and the evaporation amount is small, and the baffle plate 2m is set relatively steep to increase the descending speed of the slices. In the tower body, the phenomenon that the descending speed of the slices in the upper part is slow and the descending speed of the slices in the lower part is fast appears, greatly reducing the possibility of blockage in the tower. The splicing seams of adjacent two layers of baffle plates 2m are staggered from each other, and a small amount of slices falling from the splicing seams will all fall on the baffle plate 2m of the next layer, avoiding the long-height blanking short circuit of the slices.

[0044] The above is only the preferred and feasible embodiment of the present invention, and does not limit the patent protection scope of the present invention. In addition to the above embodiments, the present invention can also have other implementation manners. For example, the gas heater can adopt heat medium heating. All technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope required by the present invention. The technical features not described in the present invention can be realized by or adopted the existing technologies, and will not be elaborated here.

Claims

1. A slicing drying and tetrahydrofuran removal system, including an intermediate bin for slices, wherein a discharge valve for the intermediate bin is provided at the bottom of the intermediate bin for slices, and is characterized in that: The outlet of the intermediate silo discharge valve is connected to the slice inlet at the top of the first slice drying tower through the first pneumatic conveying pipeline. The slice outlet at the bottom of the first slice drying tower is connected to the inlet of the drying tower discharge valve. The outlet of the drying tower discharge valve is connected to the slice inlet at the top of the second slice drying tower through the second pneumatic conveying pipeline. The slice outlet at the bottom of the second slice drying tower is connected to the main inlet of the mixing silo. The outlet of the mixing silo is connected to the vacuum packaging machine; The first slice drying tower and the second slice drying tower respectively include a vertical cylindrical tower body. The slice inlet is provided at the center of the top of the tower body. The hot air outlet of the tower body is located on one side of the slice inlet. The hot air inlet of the tower body is provided at the lower part of the tower body. The bottom of the tower body is connected with a drying tower hopper. The slice outlet is located at the lower end of the drying tower hopper. A plurality of conical baffle caps are arranged along the axis of the tower body. Except for the top baffle cap, baffles coaxial with them are respectively provided above each baffle cap and below the bottom baffle cap. Each baffle is in the shape of a flared mouth with a larger upper part and a smaller lower part; The upper ends of the baffles are respectively connected to the inner wall of the tower body. Each baffle is a thin-walled cavity structure. The lower walls of the baffles are respectively connected to the corresponding baffle air supply ring pipes through a plurality of uniformly distributed radial connecting pipes. Each baffle air supply ring pipe surrounds the outer periphery of the tower body and is respectively provided with a baffle hot air interface. A plurality of baffle hot air holes are uniformly distributed on the upper walls of the baffles; Each baffle is formed by splicing a plurality of fan-shaped plates arranged in an annular array. The splicing seams of adjacent two layers of baffles are staggered from each other, and the angle between the baffle and the axis of the tower body is smaller closer to the bottom of the tower body; PBS type slices enter the inner cavity of the tower body from the slice inlet at the top, first fall on the outer conical surface of the top baffle cap, splash and then evenly scatter around, then fall downward on the inner conical surface of the baffle, splash towards the center again and fall through the central hole of the baffle and fall on the outer conical surface of the lower baffle cap; Hot nitrogen or hot air enters the inner cavities of the baffles from the baffle air supply ring pipes along the radial connecting pipes, and sprays upward from the baffle hot air holes on the upper walls of the baffles. When the slices fall on the baffles, they are heated by the baffles and dried and agitated by the hot air sprayed from the baffle hot air holes, further improving the drying effect and uniformity; After the above evaporation, the water and tetrahydrofuran in the PBS type slices are removed and then vacuum packaged to avoid degradation.

2. The slicing drying and tetrahydrofuran removing system according to claim 1, wherein: The hot air outlets at the tops of the first slice drying tower and the second slice drying tower are both connected to the inlet of the dust collector through the dust removal suction pipes. The top air outlet of the dust collector is connected to the air supply make-up port of the third pneumatic conveying pipeline through the return air pipeline. The inlet of the third pneumatic conveying pipeline is connected to the outlet of the slice batching valve. The inlet of the slice batching valve is connected to the outlet of the slice batching hopper. The outlet of the third pneumatic conveying pipeline is connected to the auxiliary inlet of the mixing silo.

3. The slicing drying and tetrahydrofuran removing system according to claim 2, wherein: A slicing outlet at the bottom of the second slicing drying tower is equipped with a drying tower Y-shaped three-way pipe. Two outlets of the drying tower Y-shaped three-way pipe are respectively connected to the main feeding ports of the two mixing bins, and the outlets of the third pneumatic conveying pipeline are respectively connected to the auxiliary feeding ports of the two mixing bins. Bottom outlets of the two mixing bins are respectively equipped with mixing bin Y-shaped three-way pipes. The outlets of the mixing bin Y-shaped three-way pipes are respectively connected to the feeding ports of a first vacuum packaging machine and a second vacuum packaging machine.

4. The slicing drying and tetrahydrofuran removing system according to claim 2, wherein: The main feeding port is located at the top center of the mixing bin. The auxiliary feeding ports are symmetrically located on both sides of the main feeding port. The inner cavity of the mixing bin is provided with at least three mixing chutes. Each mixing chute extends vertically and is symmetrically distributed around the axis of the mixing bin. The lower ends of the mixing chutes bend towards the conical hopper at the bottom of the mixing bin. A plurality of material discharging cross-sections are evenly arranged along the height direction of each mixing chute. Each material discharging cross-section is provided with a material discharging port. Each material discharging port is spirally distributed along the circumference of the mixing chute.

5. The slicing drying and tetrahydrofuran removal system according to claim 1, wherein: A nitrogen or compressed air pipe is connected to the air inlet of the gas heater. The air outlet of the gas heater is connected to the hot air main pipe. The hot air main pipe is respectively connected to the hot air branch pipes of each layer. The hot air branch pipes of each layer and the cold air branch pipes of the same layer are jointly connected to the baffle air supply pipe of this layer. The outlets of the baffle air supply pipes of each layer are respectively connected to the baffle hot air interfaces of this layer. A hot air temperature sensor is installed on the hot air main pipe. The hot side inlet of the gas heater is connected to the steam pipe through a heat supply regulating valve. The hot side outlet of the gas heater is connected to the condensate pipe. The opening degree of the heat supply regulating valve is controlled by the temperature measured by the hot air temperature sensor. Baffle air supply temperature sensors are respectively installed on the baffle air supply pipes of each layer. Cold air regulating valves are respectively installed on the cold air branch pipes of each layer. The opening degrees of the cold air regulating valves are respectively controlled by the temperatures measured by the baffle air supply temperature sensors of the same layer.

6. The slicing drying and tetrahydrofuran removal system according to claim 1, characterized in that: The upper end diameter of the drying tower conical hopper is larger than the diameter of the tower body. The lower end of the tower body is inserted into the upper port of the drying tower conical hopper. An annular seal cover is provided at the upper port of the drying tower conical hopper. The inner edge of the annular seal cover is welded to the outer wall of the tower body. The annular cavity below the annular seal cover is connected to the tower body air supply ring pipe through a plurality of evenly distributed radial connecting pipes. A tower body hot air inlet is provided on the circumference of the tower body air supply ring pipe. An annular hot air channel with a downward opening is provided between the lower port of the tower body and the inner wall of the drying tower conical hopper.

7. The slicing drying and tetrahydrofuran removing system according to claim 1, wherein: A stirring rotor is provided in the lower part of the drying tower conical hopper. The stirring rotor includes a stirring shaft and a plurality of stirring disk plates fixed on the stirring shaft. Both ends of the stirring shaft are respectively supported on the drying tower conical hopper through bearing seats and are sealed with the drying tower conical hopper wall. The diameter of the stirring disk plates gradually decreases from the middle section of the stirring shaft to both ends.

8. The slicing drying and tetrahydrofuran removing system according to claim 7, characterized in that: The lower end of the drying tower conical hopper is nested with a discharge cone. The upper port of the discharge cone is closed and nested on the outer periphery of the lower end of the drying tower conical hopper. The annular cavity on the outer periphery of the lower end of the drying tower conical hopper is connected to the discharge cone air supply ring pipe through multiple evenly distributed radial connecting pipes. The discharge cone hot air interface is provided on the circumference of the discharge cone air supply ring pipe. An annular hot air channel with a downward opening is provided between the lower port of the drying tower conical hopper and the inner wall of the discharge cone. The slice discharge port is located at the lower end of the discharge cone.

9. The slicing drying and tetrahydrofuran removal system according to claim 8, characterized in that: A manhole communicating with the inner cavity is provided on the circumferential wall of the discharge cone. Manholes are respectively provided on the circumferences of the upper and middle parts of the tower body.

10. The slicing drying and THF removing system according to any one of claims 1 to 9, characterized in that: A plurality of tower body temperature measurement interfaces are provided on the tower body along the height direction, and drying tower temperature transmitters are respectively installed in each tower body temperature measurement interface; a plurality of level gauge interfaces are provided on the tower body along the height direction, and level alarms are respectively installed in each level gauge interface.

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