A method and device for preparing polyester fiber

Abstract

This invention discloses a method and equipment for preparing polyester fibers, including the steps of chip drying, melt spinning, and post-treatment. The chip drying step is performed by a drying tower, a drying hot gas source, a rectifier plate, and a traction device. Specifically, the traction device applies a horizontal pulling force to the rectifier plate, causing the outer wall of the rectifier plate to adhere to the inner wall of the drying tower. Drying hot gas is then introduced into the bottom of the drying tower, correcting fluid distortion through several pores. After the drying hot gas forms a stable flow field inside the drying tower, polyester chips are fed into the drying tower through the feed port. The gas flows uniformly within the drying tower, and the falling action of the polyester chips exhibits plunger flow characteristics, thereby increasing the drying speed of the polyester chips and improving the preparation efficiency of polyester fibers. Simultaneously, it avoids material collapse, and the rectifier plate contracts automatically due to its own elasticity without external force, not hindering the discharge of polyester chips.

Description

Technical Field

[0001] This invention relates to the field of polyester fiber preparation, and more specifically to a method for preparing polyester fibers.

[0002] The present invention also relates to an apparatus for preparing polyester fibers. Background Technology

[0003] The related technologies concerning the preparation method and equipment for polyester chips disclosed in this invention are disclosed in:

[0004] The drying tower disclosed in Chinese Patent Publication No. CN2192858Y;

[0005] Chinese Patent Publication No. CN111219950A discloses a drying tower for polyester chips;

[0006] A drying system for nylon 6 chips is disclosed in Chinese Patent Publication No. CN213090289U;

[0007] During the drying process of polyester chips in the drying tower, attention should be paid to the distribution of airflow inside the drying tower. The airflow distribution inside the drying tower should be as uniform as possible to ensure that the polyester chips dry at a uniform speed and to prevent material collapse inside the drying tower.

[0008] To achieve this goal, related technologies employ the use of annular nozzles to inject nitrogen gas inside the drying tower, or the installation of a cone above the nozzles, to ensure that the gas flows as uniformly as possible within the drying tower. The uniformity of the gas flow inside the drying tower determines the drying speed of the polyester chips. Therefore, people have been trying to improve the drying tower to enhance the uniformity of the drying airflow distribution inside it. Summary of the Invention

[0009] The purpose of this invention is to provide a method and apparatus for preparing polyester fibers, in order to solve the technical problem that uneven distribution of the rising hot airflow inside the drying tower reduces the drying speed of polyester chips, thereby affecting the preparation efficiency of polyester fibers.

[0010] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0011] This application provides a method for preparing polyester fibers, comprising the following steps: chip drying, melt spinning, and post-treatment; the chip drying step is performed by a drying device, which includes: a drying tower, a drying heat source, a rectifier plate, and a traction device; the rectifier plate is horizontally placed inside the drying tower, and a plurality of pores are formed on the rectifier plate, the length direction of the pores being parallel to the axis of the drying tower, and the pore diameter being smaller than the particle size of the polyester chips; the rectifier plate is elastic, and when not being tractioned, the rectifier plate contracts horizontally inward; the traction device is used to apply a horizontal outward traction force to the rectifier plate, so that the outer wall of the rectifier plate fits against the inner wall of the drying tower, and the cross-sectional shape of the rectifier plate is... The shape presents a honeycomb pattern; the drying steps of the slices include: the traction device applies a horizontal pulling force to the rectifier plate, so that the outer wall of the rectifier plate is in contact with the inner wall of the drying tower, and then hot drying gas is introduced into the bottom of the drying tower, and the distorted fluid is corrected through a number of pores; after the hot drying gas forms a stable flow field inside the drying tower, polyester slices are fed into the drying tower through the feed port, and the polyester slices fall in a plunger shape above the rectifier plate; when the drying is finished, the pulling force applied to the rectifier plate by the traction device is released, and the rectifier plate contracts so that a gap appears between the outer wall of the rectifier plate and the inner wall of the drying tower, and the polyester slices move through the gap to the discharge port of the drying tower.

[0012] This application provides a polyester fiber preparation apparatus, comprising: a drying tower, a drying heat source, and a rectifier; the drying tower has a feed port and a discharge port at its top and bottom, respectively; polyester chips enter the interior of the drying tower through the feed port and exit through the discharge port; the rectifier is disposed inside the drying tower and near the discharge port; the output end of the drying heat source is located inside the drying tower and between the rectifier and the discharge port; the rectifier includes: a rectifier plate and a traction device; the rectifier plate is horizontally placed inside the drying tower, and a plurality of pores are formed on the rectifier plate, the length direction of which is parallel to the axis of the drying tower. The pore size is smaller than the particle size of the polyester chips; the rectifier plate is elastic, and when the rectifier plate is pulled outward by a horizontal force, the outer wall of the rectifier plate fits against the inner wall of the drying tower, and the cross-sectional shape of the rectifier plate presents a honeycomb pattern; when the rectifier plate is not pulled, it contracts horizontally inward, and a gap appears between the outer wall of the rectifier plate and the inner wall of the drying tower, through which the polyester chips can move to the discharge port; the traction device is located on the outside of the drying tower, and the actuator of the traction device horizontally penetrates the drying tower and connects to the side wall of the rectifier plate, and the traction device is used to apply a horizontal outward traction force to the rectifier plate.

[0013] Furthermore, the rectifier also includes: a cover plate; the cover plate covers the top of the rectifier plate, the cover plate is rigid, and when the rectifier plate is pulled outward by a horizontal force, the cross-sectional shape of the cover plate is the same as the cross-sectional shape of the rectifier plate; the cover plate includes: a first perforated plate and a second perforated plate; both the first perforated plate and the second perforated plate are semi-circular and rigid, the chords of the first perforated plate and the second perforated plate are parallel to each other and hinged, the first perforated plate is hinged to one side of the top of the rectifier plate, and the second perforated plate is hinged to the other side of the top of the rectifier plate, the first perforated plate and the second perforated plate are covered with a plurality of vent holes, the diameter of the vent holes being smaller than the particle size of the polyester chips; when the rectifier plate contracts, the hinged portion of the first perforated plate and the second perforated plate arches upward to form a slope where the polyester chips are difficult to stay.

[0014] Furthermore, the rectifier plate includes a cylindrical body and a plurality of hollow units, the plurality of hollow units being adjacent to each other and densely distributed inside the cylindrical body, the cross-section of the hollow units following a two-dimensional expansion pattern.

[0015] Furthermore, both the cylindrical body and the hollow unit are made of sheet material; wherein, the cylindrical body is elastic and stretchable, and its circumference extends as it is pulled; the hollow unit is elastic but not stretchable, and the area of ​​its internal cavity expands as it is pulled.

[0016] Furthermore, without external force, the cylindrical body is elliptical in shape, and the two-dimensional expansion pattern is a concave hexagon; when the cylindrical body is pulled into a perfect circle by the traction device, the two-dimensional expansion pattern is pulled into a convex hexagon, and several hollow units are adjacent to each other to form a honeycomb pattern.

[0017] Furthermore, the first perforated plate and the second perforated plate are hinged together by a mandrel, and a hollow rotating shaft is provided on the side of the first perforated plate and the second perforated plate that is far away from each other. The hollow rotating shaft is hinged to the lugs on both sides of the top of the rectifier plate.

[0018] Further, the traction device includes: a connector, an elastic element, a transmission element, and a linear actuator; two transmission elements are symmetrically arranged on both sides of the exterior of the drying tower, and the actuators of the two linear actuators are respectively connected to the two transmission elements, with the driving directions of the two linear actuators being opposite to each other; each transmission element is connected to the rectifier plate through the connector and the elastic element, the connector passes through the drying tower and is slidably connected to the drying tower, the connection between the connector and the drying tower is sealed, the elastic element is located between the transmission element and the connector, and when the transmission element moves in a direction away from the drying tower, the elastic element generates internal force.

[0019] Furthermore, the connecting member is a plurality of parallel steel cables, the elastic element is a tension spring, each of the steel cables is connected to the transmission member through a tension spring, the transmission member is a rectangular hollow frame, and the linear actuator is a cylinder.

[0020] Compared with the prior art, this application has the following advantages:

[0021] A method and apparatus for preparing polyester fibers are provided. The chip drying process is performed by a drying device. The drying device uses a rectifier plate that presents a honeycomb pattern when horizontally stretched to regulate the airflow inside the drying tower, so that the gas inside the drying tower flows evenly. The falling action of the polyester chips in the drying tower exhibits the characteristics of plunger flow, thereby improving the drying speed of the polyester chips and thus improving the preparation efficiency of polyester fibers. At the same time, it avoids material collapse. Furthermore, the rectifier plate shrinks on its own due to its elasticity without external force, which does not hinder the discharge of polyester chips. Attached Figure Description

[0022] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0023] Figure 1 This is a front view of Embodiment 1 of the present invention;

[0024] Figure 2 for Figure 1 A cross-sectional view along the AA direction, showing the rectifier in its retracted state;

[0025] Figure 3 for Figure 2 A schematic diagram of another state, showing the expanded state of the rectifier plate;

[0026] Figure 4 for Figure 1 A cross-sectional view along the BB direction;

[0027] Figure 5 This is a schematic diagram of Embodiment 2 of the present invention. Figure 5 and Figure 4 They are the same cutting plane;

[0028] Figure 6 This is a perspective view of the rectifier plate and cover plate of Embodiment 2 of the present invention. The figure shows the working state of the cover plate arching upward in the middle when the rectifier plate retracts.

[0029] Figure 7This is an assembly diagram of the rectifier plate and cover plate according to Embodiment 2 of the present invention;

[0030] The labels in the diagram represent the following:

[0031] 1-Drying tower; 11-Feed inlet; 12-Discharge inlet; 13-Void;

[0032] 2-Dry heat source;

[0033] 3-Rectifier plate; 31-Aperture; 32-Cylinder body; 33-Hollow unit; 34-Hanging lug;

[0034] 4-Traction device; 41-Connecting component; 42-Elastic component; 43-Transmission component;

[0035] 5-Cover plate; 51-First perforated plate; 52-Second perforated plate; 53-Ventilation hole; 54-Mandrel; 55-Hollow rotating shaft. Detailed Implementation

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] The preparation method of polyester fiber includes the steps of chip drying, melt spinning and post-treatment. Among them, there is a technical problem of uneven distribution of drying airflow in the chip drying step, which directly affects the drying speed of the chips and thus affects the preparation efficiency of polyester fiber.

[0038] To make the distribution of the drying airflow more uniform, a rectification structure needs to be arranged inside the drying tower. Among the many rectification structures, the honeycomb panel has the best rectification effect. However, if the honeycomb panel is placed horizontally inside the drying tower 1, the drying tower 1 will not be able to discharge material. If the size of the pores of the honeycomb panel is designed to be larger than the particle size of the polyester chips, the polyester chips will block the air vents 53 of the honeycomb panel, resulting in a decrease in its rectification effect.

[0039] To address this problem, a polyester fiber preparation apparatus is provided; please refer to [reference needed]. Figure 1 , 2 Example 1 is shown in 3 and 4.

[0040] The drying device includes: a drying tower 1, a drying heat source 2, and a rectifier;

[0041] The top and bottom of the drying tower 1 are respectively provided with a feed port 11 and a discharge port 12. Polyester chips enter the interior of the drying tower 1 through the feed port 11 and exit through the discharge port 12. The rectifier is located inside the drying tower 1 and close to the discharge port 12. The output end of the drying hot air source 2 is located inside the drying tower 1 and between the rectifier and the discharge port 12.

[0042] The rectifier includes: a rectifier plate 3 and a traction device 4;

[0043] The rectifier plate 3 is horizontally placed inside the drying tower 1. Several pores 31 are formed on the rectifier plate 3. The length direction of the pores 31 is parallel to the axis of the drying tower 1. The pore diameter of the pores 31 is smaller than the particle size of the polyester chips.

[0044] The rectifier plate 3 is elastic. When the rectifier plate 3 is pulled outward by a horizontal force, the outer wall of the rectifier plate 3 fits against the inner wall of the drying tower 1, and the cross-sectional shape of the rectifier plate 3 presents a honeycomb pattern.

[0045] When the rectifier plate 3 is not pulled, it retracts horizontally inward, and a gap 13 appears between the outer wall of the rectifier plate 3 and the inner wall of the drying tower 1.

[0046] The traction device 4 is located on the outside of the drying tower 1. The actuator of the traction device 4 passes horizontally through the drying tower 1 and is connected to the side wall of the rectifier plate 3. The traction device 4 is used to apply a horizontal outward traction force to the rectifier plate 3.

[0047] Dry hot gas refers to gas with a dew point below -30°C. It is usually made of nitrogen supplied by a gas supply station, which is heated to 150°C~185°C and introduced into the bottom of drying tower 1. Alternatively, clean indoor air can be used, which is dehumidified, heated and then introduced into the bottom of drying tower 1.

[0048] After absorbing moisture, the hot air exchanges heat with the dry gas introduced into drying tower 1 and is then discharged into the atmosphere.

[0049] The traction device 4 uses a pneumatic cylinder, hydraulic cylinder, or servo electric push rod. The traction device 4 is connected to the rectifier plate 3 via a steel wire or connecting rod. The steel wire or connecting rod is slidably connected to the drying tower 1, and the connection part is sealed.

[0050] The drying process in Example 1 includes the following steps:

[0051] like Figure 3 As shown, before the drying hot gas is introduced into the drying tower 1, the traction device 4 pulls the rectifier plate 3 to both sides. The rectifier plate 3 is stretched until it fits against the inner wall of the drying tower 1. The drying hot nitrogen gas passes through the honeycomb-shaped pores 31, which corrects the distorted fluid, stabilizes the flow field distribution, and eliminates vortices, crossflows, etc.

[0052] After the drying gas forms a stable flow field inside the drying tower 1, pre-crystallized polyester chips are introduced from the top of the drying tower 1. The polyester chips settle naturally by their own weight and continuously exchange heat with the rising hot drying gas. After the interior of the drying tower 1 is filled with polyester chips, drying continues for 3 to 5 hours.

[0053] like Figure 2 As shown, after the drying operation is completed, the traction device 4 releases the traction on the rectifier plate 3. The rectifier plate 3 contracts under its own elastic force, so that a gap 13 appears between the outer wall of the rectifier plate 3 and the inner wall of the drying tower 1. The polyester chips fall from the gap 13 and then leave the drying tower 1 from the discharge port 12.

[0054] Under the action of the rectifier plate 3, the polyester chips flow in the drying tower 1 via a plunger.

[0055] Plunger flow refers to the phenomenon where polyester chips are pushed upwards by gas like a piston, then the particles fall downwards from the top of the plunger, and finally the plunger dissipates. This stable, pulsating, and repetitive flow phenomenon is called plunger flow, and it is sometimes also referred to as "thrusting".

[0056] Optional:

[0057] The rectifier plate 3 includes a cylindrical body 32 and a plurality of hollow units 33. The hollow units 33 are adjacent to each other and densely distributed inside the cylindrical body 32. The cross-section of the hollow units 33 follows a two-dimensional expansion pattern.

[0058] Specifically:

[0059] Both the cylindrical body 32 and the hollow unit 33 are made of sheet material, wherein:

[0060] The cylinder 32 is elastic and stretchable, and its circumference stretches as it is pulled.

[0061] The hollow unit 33 is elastic but not stretchable, and the area of ​​its internal cavity expands as it is pulled.

[0062] Optional:

[0063] Without external force, the shape of the cylinder 32 is elliptical, and the two-dimensional expansion pattern is a concave hexagon.

[0064] When the cylinder body 32 is pulled into a perfect circle by the traction device 4, the hollow unit 33 is pulled into a convex hexagon, and several hollow units 33 are adjacent to each other to form a honeycomb pattern.

[0065] Furthermore, since the top surface of the rectifier plate 3 is flat, a portion of the polyester chips located directly above the rectifier plate 3 are difficult to fall off after the rectifier plate 3 retracts. To solve this problem, please refer to... Figure 5 , 6 Example 2 shown in Figure 7:

[0066] Based on Embodiment 1, a cover plate 5 is added to the rectifier. The cover plate 5 covers the top of the rectifier plate 3. The cover plate 5 is rigid. When the rectifier plate 3 is pulled outward by a horizontal force, the cross-sectional shape of the cover plate 5 is the same as the cross-sectional shape of the rectifier plate 3.

[0067] The cover plate 5 includes a first perforated plate 51 and a second perforated plate 52. Both the first perforated plate 51 and the second perforated plate 52 are semi-circular and rigid. The chords of the first perforated plate 51 and the second perforated plate 52 are parallel to each other and hinged. The first perforated plate 51 is hinged to one side of the top of the rectifier plate 3, and the second perforated plate 52 is hinged to the other side of the top of the rectifier plate 3. The first perforated plate 51 and the second perforated plate 52 are covered with a number of ventilation holes 53. The pore size of the ventilation holes 53 is smaller than the particle size of the polyester chips.

[0068] When the rectifier plate 3 contracts, the hinge joint of the first perforated plate 51 and the second perforated plate 52 arches upward to form a slope where the polyester chips are difficult to stay.

[0069] The drying process in Example 2 further includes the following steps:

[0070] like Figure 4 As shown, after the rectifier plate 3 contracts, the polyester chips on both sides of the rectifier plate 3 fall from the gap 13, and the polyester chips above the rectifier plate 3 flow along the inclined first perforated plate 51 and second perforated plate 52 to both sides of the rectifier plate 3, and then leave the drying tower 1 from the discharge port 12.

[0071] Optional:

[0072] The first perforated plate 51 and the second perforated plate 52 are hinged together by a spindle 54. Hollow rotating shafts 55 are provided on the sides of the first perforated plate 51 and the second perforated plate 52 that are far apart from each other. The hollow rotating shafts 55 are hinged to the lugs 34 on both sides of the top of the rectifier plate 3.

[0073] On the other hand, in Embodiments 1 and 2, the rectifier plate 3 is pulled from an ellipse into a perfect circle, and the pulling distance of each part is different. Therefore, the rectifier plate 3 cannot be simply pulled by a linear actuator such as a cylinder or a servo electric push rod.

[0074] The traction device 4 includes: a connector 41, an elastic element 42, a transmission element 43, and a linear drive;

[0075] Two transmission components 43 are symmetrically arranged on both sides of the outside of the drying tower 1. The actuators of the two linear drives are respectively connected to the two transmission components 43, and the driving directions of the two linear drives are opposite to each other.

[0076] Each transmission component 43 is connected to the rectifier plate 3 via a connector 41 and an elastic component 42. The connector 41 passes through the drying tower 1 and is slidably connected to the drying tower 1. The connection between the connector 41 and the drying tower 1 is sealed. The elastic component 42 is located between the transmission component 43 and the connector 41. When the transmission component 43 moves away from the drying tower 1, the elastic component 42 generates internal force.

[0077] The elastic element 42 adapts to the different traction distances of various parts of the rectifier plate 3 by extending and retracting on its own, without affecting the transmission of the pulling force from the transmission element 43 to the connecting element 41.

[0078] Optional:

[0079] The connector 41 uses several parallel steel cables, the elastic element 42 uses a tension spring, and each steel cable is connected to the transmission element 43 through a tension spring. The transmission element 43 uses a rectangular hollow frame, and the linear actuator uses a cylinder, which is not shown in the figure.

[0080] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered as falling within the scope of protection of the embodiments of the present invention.

Claims

1. A device for preparing polyester fibers, Its features are, include: Drying tower, drying heat source and rectifier; The top and bottom of the drying tower are respectively provided with a feed port and a discharge port. Polyester chips enter the interior of the drying tower from the feed port and exit through the discharge port. The rectifier is located inside the drying tower and close to the discharge port. The output end of the drying hot gas source is located inside the drying tower and between the rectifier and the discharge port. The rectifier includes: a rectifier plate and a traction device; The rectifier plate is horizontally placed inside the drying tower. The rectifier plate has a number of pores. The length direction of the pores is parallel to the axis of the drying tower. The pore diameter is smaller than the particle size of the polyester chips. The rectifier plate is elastic. When the rectifier plate is pulled outward by a horizontal force, the outer wall of the rectifier plate fits against the inner wall of the drying tower, and the cross-sectional shape of the rectifier plate presents a honeycomb pattern. When the rectifier plate is not pulled, it retracts horizontally inward, and a gap appears between the outer wall of the rectifier plate and the inner wall of the drying tower, through which the polyester chips can move to the discharge port; The traction device is located on the outside of the drying tower. The actuator of the traction device extends horizontally through the drying tower and is connected to the side wall of the rectifier plate. The traction device is used to apply a horizontal outward traction force to the rectifier plate. The rectifier also includes: a cover plate; The cover plate covers the top of the rectifier plate. The cover plate is rigid. When the rectifier plate is pulled outward by a horizontal force, the cross-sectional shape of the cover plate is the same as the cross-sectional shape of the rectifier plate. The cover plate includes: a first perforated plate and a second perforated plate; Both the first porous plate and the second porous plate are semi-circular and rigid. The chords of the first porous plate and the second porous plate are parallel to each other and hinged. The first porous plate is hinged to one side of the top of the rectifier plate, and the second porous plate is hinged to the other side of the top of the rectifier plate. The first porous plate and the second porous plate are covered with a plurality of ventilation holes, and the pore size of the ventilation holes is smaller than the particle size of the polyester chips. When the rectifier plate contracts, the hinge joint of the first perforated plate and the second perforated plate arches upward to form a slope that makes it difficult for polyester chips to stay.

2. The polyester fiber preparation equipment according to claim 1, characterized in that, The rectifier plate includes a cylindrical body and a plurality of hollow units, which are adjacent to each other and densely distributed inside the cylindrical body. The cross-section of the hollow units follows a two-dimensional expansion pattern.

3. The polyester fiber preparation equipment according to claim 2, characterized in that, Both the cylindrical body and the hollow unit are made of sheet material; in, The cylinder is elastic and stretchable, and its circumference stretches as it is pulled. The hollow unit is elastic but not stretchable, and the area of ​​its internal cavity expands as it is pulled.

4. The polyester fiber preparation equipment according to claim 3, characterized in that, Without external force, the shape of the cylinder is elliptical, and the two-dimensional expansion pattern is a concave hexagon. When the cylinder body is stretched into a perfect circle by the traction device, the two-dimensional expansion pattern is stretched into a convex hexagon, and several hollow units are adjacent to each other to form a honeycomb pattern.

5. The polyester fiber preparation equipment according to claim 1, characterized in that, The first perforated plate and the second perforated plate are hinged together by a mandrel. A hollow rotating shaft is provided on the side of the first perforated plate and the second perforated plate that is far away from each other. The hollow rotating shaft is hinged to the lugs on both sides of the top of the rectifier plate.

6. The polyester fiber preparation equipment according to claim 1, characterized in that, The traction device includes: a connector, an elastic element, a transmission element, and a linear driver; The two transmission components are symmetrically arranged on both sides of the outside of the drying tower. The actuators of the two linear actuators are respectively connected to the two transmission components, and the driving directions of the two linear actuators are opposite to each other. Each of the transmission components is connected to the rectifier plate via the connector and the elastic element. The connector passes through the drying tower and is slidably connected to the drying tower. The connection between the connector and the drying tower is sealed. The elastic element is located between the transmission component and the connector. When the transmission component moves in a direction away from the drying tower, the elastic element generates internal force.

7. The polyester fiber preparation equipment according to claim 6, characterized in that, The connecting element is a plurality of parallel steel cables, the elastic element is a tension spring, each steel cable is connected to the transmission element through a tension spring, the transmission element is a rectangular hollow frame, and the linear actuator is a cylinder.

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