Dryer

Abstract

To provide a dryer capable of downsizing a facility.SOLUTION: A dryer includes a casing, a rotation shaft disposed in the casing and extending from one end side in the longer direction of the casing toward the other end side, a screw blade spirally wound around an outer peripheral surface at the one end side of the rotation shaft for transportation of an object to be dried input in the casing from one end side toward the other end side along rotation of the rotation shaft, and a lifter attached to an outer peripheral surface of the other end side in the rotation axis for agitation of the object to be dried transported from the one end side toward the other end side by the screw blade.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a dryer. [Background technology]

[0002] For example, various dryers have been proposed for drying materials (hereinafter simply referred to as materials to be dried), such as sewage sludge (hereinafter simply referred to as sludge) before incineration (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 041594 Summary of the Invention [Problem to be solved by the invention]

[0004] In the dryer as described above, it is desired to reduce the size of the equipment while maintaining the capacity to sufficiently perform necessary processes such as drying the material to be dried. [Means for solving the problem]

[0005] In order to achieve the above-mentioned miniaturization of equipment, the dryer of the present invention comprises a casing, a rotating shaft provided within the casing and extending from one end side to the other end side in the longitudinal direction of the casing, a screw blade attached in a spiral shape to the outer circumferential surface of the one end side of the rotating shaft and transporting the material to be dried placed into the casing from the one end side to the other end side as the rotating shaft rotates, and a lifter attached to the outer circumferential surface of the other end side of the rotating shaft and agitating the material to be dried transported from the one end side to the other end side by the screw blade. Effect of the Invention

[0006] According to the dryer of the present invention, the equipment can be made compact. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an overall cross-sectional view of a dryer 10 according to the first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of the dryer 10 taken along line AA in the first embodiment. [Diagram 3] FIG. 3 is an overall cross-sectional view of the dryer 10 according to the first modified example. [Figure 4] FIG. 4 is a diagram for explaining the filling rate of the sludge 1 inside the casing 11. As shown in FIG. [Diagram 5] FIG. 5 is an overall cross-sectional view of the dryer 10 according to the second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. However, such descriptions should not be interpreted in a limiting sense and do not limit the subject matter described in the claims. In addition, various changes, substitutions, and modifications can be made without departing from the spirit and scope of the present disclosure. In addition, different embodiments can be appropriately combined.

[0009] [Dryer 10 in the first embodiment] First, the dryer 10 in the first embodiment will be described. Fig. 1 and Fig. 2 are configuration diagrams of the dryer 10 in the first embodiment. Specifically, Fig. 1 is an overall cross-sectional view of the dryer 10 in the first embodiment. Also, Fig. 2 is an AA cross-sectional view of the dryer 10 in the first embodiment. Note that the shape, size, etc. of the dryer 10 shown in Fig. 1 etc. are merely examples and are not limited thereto.

[0010] The dryer 10 is a device that is installed, for example, before an incinerator (not shown) that incinerates sludge 1 (hereinafter also referred to as material to be dried 1), and dries the sludge 1 before it is supplied to the incinerator to reduce the moisture content. That is, the dryer 10 is a device that reduces the moisture content of the sludge 1 to a level that allows spontaneous combustion in the incinerator.

[0011] Specifically, as shown in FIG. 1, the dryer 10 has, for example, a drying chamber 10a for drying sludge 1, and a mixing chamber 10b for mixing the sludge 1 with sand 2 (hereinafter also referred to as granular material 2).

[0012] As shown in FIG. 1, the dryer 10 includes, for example, a casing 11, a screw shaft 12 (hereinafter also referred to as a rotating shaft 12), a screw blade 13, and a lifter 14.

[0013] The casing 11 is, for example, a hollow cylindrical casing extending in the X-axis direction. Specifically, the casing 11 is configured, for example, with a cylindrical side wall 11a extending along the X-axis, a fixed plate 11b forming an end portion on the X1 direction side (hereinafter also referred to as one end side), and a fixed plate 11c forming an end portion on the X2 direction side (hereinafter also referred to as the other end side). That is, the fixed plate 11b is attached, for example, so as to close the end portion on the X1 direction side of the side wall 11a. Also, the fixed plate 11c is attached, for example, so as to close the end portion on the X2 direction side of the side wall 11a.

[0014] The casing 11 is also provided with an inlet 11d for introducing sludge 1 into the casing 11, for example, near the fixed plate 11b on the side wall 11a. The casing 11 is also provided with an inlet 11e for introducing sand 2 into the casing 11, for example, near the middle position in the X-axis direction on the side wall 11a (for example, near the boundary between the drying chamber 10a and the mixing chamber 10b).

[0015] The casing 11 is also provided with an outlet 11f, for example at the fixed plate 11c, for discharging the mixture 3 from inside the casing 11. The mixture 3 is, for example, a mixture of sludge 1 (sludge 1 after being dried in the drying chamber 10a) and sand 2. The casing 11 is also provided with an outlet 11g, for example at the fixed plate 11c, for discharging the drying exhaust gas 4 (hereinafter also simply referred to as exhaust gas 4) from inside the casing 11. The exhaust gas 4 is, for example, a gas such as water vapor discharged as the sludge 1 is dried.

[0016] In the following, as shown in FIG. 1, a case where the input port 11d and the input port 11e are provided on the Z1 direction side (upper side) of the side wall 11a will be described, but the present invention is not limited thereto. Specifically, the input port 11d and the input port 11e may be provided, for example, at a position other than the Z1 direction side of the side wall 11a (for example, at the fixed plate 11b). In the following, as shown in FIG. 1, a case where the discharge port 11f and the discharge port 11g are provided on the fixed plate 11c will be described, but the present invention is not limited thereto. Specifically, the discharge port 11f and the discharge port 11g may be provided, for example, at a position other than the fixed plate 11c (for example, at the Z1 direction side of the side wall 11a).

[0017] The screw shaft 12 is, for example, a shaft extending along the X-axis direction, and at least one end side is led out of the casing 11 and rotatably supported by a support member (not shown). The screw shaft 12 rotates around the X-axis, for example, by driving a motor (not shown) connected to at least one end side. Specifically, the screw shaft 12 is disposed, for example, at a position where the rotation axis of the screw shaft 12 coincides with the axis of the casing 11 (side wall 11a).

[0018] The screw blade 13 is attached in a spiral shape, for example, on the outer circumferential surface of the screw shaft 12 on the X1 direction side (the outer circumferential surface of the portion located inside the drying chamber 10a). The screw blade 13 rotates, for example, in conjunction with the rotation of the screw shaft 12, and transports the sludge 1 introduced into the casing 11 from the introduction port 11d, in the X2 direction.

[0019] Here, the side wall 11a of the casing 11, the screw shaft 12, and the screw blades 13 (hereinafter collectively referred to as the screw blades 13, etc.) are each provided with, for example, a flow path (not shown) through which a heat medium (not shown) circulates inside. That is, the surfaces of the screw blades 13, etc. function as heat transfer surfaces that supply heat to the sludge 1, for example.

[0020] The sludge 1 introduced into the casing 11 is dried, for example, by contacting with the surfaces (heat transfer surfaces) of the screw blades 13, etc., during the process of being transported from the X1 direction side to the X2 direction side. That is, the sludge 1 introduced into the casing 11 is dried, for example, by indirect heating by a heat medium flowing through a flow path provided in the screw blades 13, etc.

[0021] The heat medium circulating through the flow path in the screw blade 13 and the like may be, for example, heat oil heated by waste heat from exhaust gas (not shown) generated in an incinerator. That is, the heat medium may be, for example, one heated by waste heat generated with the incineration of sludge 1 in an incinerator. The heat medium may also be, for example, heat oil heated by equipment such as a heater (not shown).

[0022] The lifter 14 is attached, for example, to the outer circumferential surface of the screw shaft 12 on the X2 direction side (the outer circumferential surface of the portion located inside the mixing chamber 10b). The lifter 14 rotates, for example, together with the screw blade 13 in conjunction with the rotation of the screw shaft 12, and agitates the sludge 1 transported by the screw blade 13 from the X1 direction side.

[0023] Specifically, the lifter 14 has, for example, an agitating member 14a that agitates the sludge 1 by contacting the sludge 1, and a connecting member 14b that connects the agitating member 14a to the screw shaft 12. As shown in Figures 1 and 2, the agitating member 14a may be, for example, a member that extends in the X-axis direction and has a rectangular cross section in the X-axis direction (i.e., a rectangular parallelepiped member). Also, the agitating member 14a may be, for example, a member that extends in the X-axis direction and has a cross section in the X-axis direction that is a shape other than a rectangle, such as an L-shape.

[0024] The lifter 14 mixes the sludge 1 and the sand 2 uniformly, for example, by stirring the sludge 1 transported by the screw blade 13 and the sand 2 charged from the charging port 11e.

[0025] That is, in the dryer 10 of the present embodiment, for example, the screw blade 13 and the lifter 14 are attached to the same screw shaft 12. In the dryer 10 of the present embodiment, for example, the rotation of the screw shaft 12 causes both the screw blade 13 and the lifter 14 to rotate.

[0026] As a result, in the dryer 10 of this embodiment, for example, by rotating the screw shaft 12, it is possible to not only dry the sludge 1 but also agitate the sludge 1 (mix the sludge 1 with the sand 2). Therefore, in the dryer 10 of this embodiment, for example, it is not necessary to provide a separate device (device other than the dryer 10) for agitating the sludge 1, and it is possible to reduce the size of the necessary equipment.

[0027] Furthermore, in dryer 10 of the present embodiment, for example, by rotating both screw blade 13 and lifter 14 by the rotation of screw shaft 12, it becomes unnecessary to have separate power for rotating screw blade 13 and power for rotating lifter 14. Therefore, in dryer 10 of the present embodiment, for example, it becomes possible to reduce the power required for drying and agitating sludge 1, and to further reduce the size of the necessary equipment.

[0028] Furthermore, in the dryer 10 of this embodiment, for example, the screw blade 13 is not attached to the outer circumferential surface of the screw shaft 12 located in the mixing chamber 10b. Therefore, the sludge 1 transported into the mixing chamber 10b by the screw blade 13 is not transported toward the X2 direction side (toward the fixed plate 11c) even if the screw blade 13 further rotates. On the other hand, the sludge 1 transported into the mixing chamber 10b gradually moves toward the X2 direction side, for example, by being pushed out by new sludge 1 transported into the mixing chamber 10b. Therefore, the speed at which the sludge 1 transported to the mixing chamber 10b moves through the mixing chamber 10b is slower than, for example, the speed at which the sludge 1 introduced into the drying chamber 10a moves through the drying chamber 10a (the speed at which the sludge 1 is transported through the drying chamber 10a by the screw blade 13).

[0029] As a result, the dryer 10 in this embodiment can ensure that the sludge 1 transported into the mixing chamber 10b by the screw blade 13 remains in the mixing chamber 10b for a sufficient period of time. Therefore, the dryer 10 in this embodiment can sufficiently mix the sludge 1 and the sand 2, for example.

[0030] Thus, the dryer 10 in this embodiment includes, for example, a casing 11 and a screw shaft 12 that is provided inside the casing 11 and extends from the X1 direction side (one end side) to the X2 direction side (other end side) in the X-axis direction (longitudinal direction) of the casing 11. The dryer 10 in this embodiment also includes, for example, a screw blade 13 that is attached in a spiral shape to the outer circumferential surface of the screw shaft 12 on the X1 direction side and transports the sludge 1 introduced into the casing 11 from the X1 direction side to the X2 direction as the screw shaft 12 rotates.

[0031] Furthermore, the dryer 10 in this embodiment includes a lifter 14 that is attached to, for example, the outer circumferential surface of the screw shaft 12 on the X2 direction side and stirs the sludge 1 transported from the X1 direction side to the X2 direction side by the screw blades 13. Specifically, the lifter 14 mixes the sludge 1 and the sand 2 by, for example, stirring the sludge 1 transported from the X1 direction side to the X2 direction side together with the sand 2 charged into the casing 11.

[0032] As a result, in the dryer 10 of this embodiment, it is possible to reduce the size of the equipment while maintaining the ability to sufficiently dry the sludge 1 and stir the sludge 1 (mix the sludge 1 with sand 2), for example.

[0033] [Dryer 10 in the first modified example] Next, the dryer 10 in the first modified example will be described. Fig. 3 is a configuration diagram of the dryer 10 in the first modified example. Specifically, Fig. 3 is an overall cross-sectional view of the dryer 10 in the first modified example.

[0034] 3, in the dryer 10 of the first modification, for example, the diameter of the screw blade 13 attached to the outer circumferential surface of a predetermined portion (hereinafter also simply referred to as the predetermined portion) of the screw shaft 12 is smaller than the diameter of the screw blade 13 attached to the outer circumferential surface of the screw shaft 12 other than the predetermined portion. The predetermined portion is, for example, a portion near the center of the screw shaft 12 in the X-axis direction.

[0035] Specifically, the screw blade 13 in the first modified example has, for example, a screw blade 13a attached to a portion of the screw shaft 12 on the X1 direction side (fixed plate 11b side) and a screw blade 13b attached to a portion of the screw shaft 12 on the X2 direction side (mixing chamber 10b side). Also, the screw blade 13 in the first modified example has, for example, a screw blade 13c provided in a portion (predetermined portion) between the screw blade 13a and the screw blade 13b on the screw shaft 12 and having a smaller diameter than the screw blade 13a and the screw blade 13b.

[0036] That is, the sludge 1 introduced into the casing 11 from the introduction port 11d is heated by the heat medium circulating inside the screw blades 13 and the like and gradually dried in the process of being transported, for example, from the X1 direction side to the X2 direction side by the screw blades 13. Therefore, the moisture in the sludge 1 introduced into the casing 11 gradually evaporates and the volume is reduced in the process of being transported, for example, from the X1 direction side to the X2 direction side.

[0037] Therefore, in the drying chamber 10a, for example, the filling rate of the sludge 1 decreases as one moves toward the X2 direction (the mixing chamber 10b side). Therefore, in the drying chamber 10a, for example, the contact area (i.e., the heat transfer area) between the surfaces of the screw blades 13 and the sludge 1 decreases as one moves toward the X2 direction, and the drying efficiency of the sludge 1 may decrease.

[0038] Therefore, in the dryer 10 of this modified example, for example, the diameter of the screw blade 13c is made smaller than the diameters of other parts (screw blade 13a and screw blade 13b), thereby reducing the amount of sludge 1 transported in the part (specified part) where the screw blade 13c is attached.

[0039] This allows the dryer 10 in this modification to make the amount of sludge transported from the portion where the screw blade 13c is attached to the portion where the screw blade 13b is attached smaller than the amount of sludge transported from the portion where the screw blade 13a is attached to the portion where the screw blade 13c is attached. Therefore, the dryer 10 in this modification can increase the filling rate of the sludge 1 in the vicinity of the position where the screw blade 13c is attached, for example.

[0040] [Sludge 1 filling rate inside the casing 11] Next, a description will be given of the filling rate of the sludge 1 inside the casing 11. FIG.

[0041] 3, the filling rate of the sludge 1 in the drying chamber 10a decreases, for example, as it moves toward the X2 direction (toward the mixing chamber 10b) due to the progress of drying of the sludge 1. Specifically, the filling rate of the sludge 1 at the position where it is transported by the screw blade 13a (hereinafter also referred to as sludge 1b) is lower than the filling rate of the sludge 1 at the position before it is transported by the screw blade 13a (hereinafter also referred to as sludge 1a), as shown in FIG.

[0042] On the other hand, as described in Fig. 3, the amount of sludge 1 transported at the portion (predetermined portion) where screw blade 13c is attached is smaller than the amount of sludge 1 transported at the portion where screw blade 13a is attached, for example. Therefore, the filling rate of the sludge 1 (hereinafter also referred to as sludge 1c) at the position where it is transported by screw blade 13c is higher than the filling rate of the sludge 1b, for example, as shown in Fig. 4. Furthermore, in this case, within the drying chamber 10a, for example, as the filling rate of the sludge 1c increases, the filling rate of the sludge 1 (hereinafter also referred to as sludge 1d) at the position where it is transported by screw blade 13b also increases.

[0043] In this manner, in this modified example, the diameter of a portion of the screw blade 13 attached to the outer peripheral surface of a specified portion of the screw shaft 12 is smaller than the diameter of another portion attached to the outer peripheral surface of the screw shaft 12 other than the specified portion.

[0044] This makes it possible to increase the filling rate of the sludge 1 (sludge 1c and sludge 1d) in the drying chamber 10a of this modified example, for example, on the X2 side (mixing chamber 10b side) of the portion (predetermined portion) where the screw blade 13c is attached. Therefore, in the drying chamber 10a of this modified example, it is possible to suppress a decrease in the contact area (heat transfer area) between the surface of the screw blade 13 and the sludge 1 in the X2 direction side of the portion where the screw blade 13c is attached, and it is possible to suppress a decrease in the drying efficiency of the sludge 1.

[0045] Therefore, in the dryer 10 of this modified example, for example, it is not necessary to increase the size of the drying chamber 10a in the X-axis direction in order to increase the contact area between the surfaces of the screw blades 13, etc. and the sludge 1. Therefore, in the dryer 10 of this modified example, it is possible to further reduce the size of necessary equipment, for example.

[0046] 3 and 4, the screw shaft 12 has one predetermined portion, but the present invention is not limited to this. Specifically, the screw shaft 12 may have a plurality of predetermined portions, for example.

[0047] [Dryer 10 in the second modified example] Next, the dryer 10 in the second modified example will be described. Fig. 5 is a configuration diagram of the dryer 10 in the second modified example. Specifically, Fig. 5 is an overall cross-sectional view of the dryer 10 in the second modified example.

[0048] As shown in FIG. 5, the screw shaft 12 in the second modified example has a rod-shaped body 15 attached, for example, to the outer peripheral surface of a portion of the screw shaft 12 to which the screw blades 13 are not attached, and extending radially of the screw shaft 12.

[0049] Specifically, the rod-shaped body 15 is attached, for example, to the outer circumferential surface of the portion (predetermined portion) of the screw shaft 12 where the screw blades 13c are attached.

[0050] That is, the sludge 1 introduced into the casing 11 from the introduction port 11d is dried by contacting, for example, with the surface (heat transfer surface) of the screw blade 13 or the like. Therefore, if there is a bias in the sludge 1 that comes into contact with the surface of the screw blade 13 or the like, for example, the sludge 1 may not be dried sufficiently (uniformly) in the drying chamber 10a. Specifically, for example, if only a portion of the sludge 1 introduced into the casing 11 continues to contact the surface of the screw blade 13 or the like, resulting in sludge 1 that barely comes into contact with the surface of the screw blade 13 or the like, the sludge 1 may not be dried sufficiently (uniformly) in the drying chamber 10a.

[0051] Therefore, in the dryer 10 of this modified example, for example, a rod-shaped body 15 is attached to the screw shaft 12, so that the rod-shaped body 15 is rotated together with the screw blades 13 and the lifter 14.

[0052] As a result, in the dryer 10 of this modified example, it is possible, for example, to bring the sludge 1 transported by the screw blade 13 into contact with the rod-shaped body 15. Therefore, in the dryer 10 of this modified example, it is possible, for example, to impede the flow of the sludge 1 transported by the screw blade 13, to shear and disperse the sludge, and to promote replacement of the sludge 1 in contact with the surfaces of the screw blade 13, etc. Therefore, in the dryer 10 of this modified example, it is possible, for example, to bring the sludge 1 introduced into the casing 11 into uniform contact with the surfaces of the screw blade 13, etc., and it is possible to sufficiently (uniformly) dry the sludge 1.

[0053] In the example shown in FIG. 5, two rod-shaped bodies 15 are attached to the screw shaft 12, but the present invention is not limited thereto. Specifically, the screw shaft 12 may have a number of rod-shaped bodies 15 other than two. In the example shown in FIG. 5, the rod-shaped bodies 15 are attached to a predetermined portion of the screw shaft 12 (a portion where the screw blade 13c is attached), but the present invention is not limited thereto. Specifically, the rod-shaped bodies 15 may be attached to a position other than the predetermined portion of the screw shaft 12 (for example, a position on the X2 direction side of the predetermined portion). In the example shown in FIG. 5, the rod-shaped bodies 15 are attached so as to extend in the radial direction of the screw shaft 12, but the present invention is not limited thereto. Specifically, the rod-shaped bodies 15 may be attached so as to extend in a direction other than the radial direction of the screw shaft 12 (for example, a direction inclined at a predetermined angle from the radial direction of the screw shaft 12 toward the X-axis direction). In the example shown in FIG. 5, the rod-shaped bodies 15 extending in one direction are attached to the screw shaft 12, but the present invention is not limited thereto. Specifically, the rod-shaped body 15 may be, for example, at least a portion of which is bent or curved. [Explanation of symbols]

[0054] 1: Sludge 1a: Sludge 1b: Sludge 1c: Sludge 1d: Sludge 2: Sand 3: Mixture 3: Exhaust gas 10: Dryer 10a: Drying room 10b: mixing chamber 11: casing 11a: Side wall 11b: Fixed plate 11c: Fixed plate 11d: Inlet 11e: Inlet 11f: Outlet 11g: Outlet 12: Screw shaft 13: Screw blade 13a: Screw blade 13b: Screw blade 13c: Screw blade 14: Lifter 14a: Stirring member 14b: connecting member 15: rod-shaped body

Claims

1. A casing; a rotating shaft provided in the casing and extending from one end side to the other end side in a longitudinal direction of the casing; a screw blade attached in a spiral shape to an outer circumferential surface of the one end side of the rotating shaft, and conveying the material to be dried input into the casing from the one end side to the other end side as the rotating shaft rotates; a lifter attached to the outer peripheral surface of the other end of the rotating shaft and configured to agitate the material to be dried which is transported from the one end to the other end by the screw blade.

2. The dryer according to claim 1 , wherein the lifter mixes the material to be dried and the granular material fed into the casing by stirring the material to be dried transported from the one end side to the other end side and the granular material fed into the casing.

3. The dryer according to claim 1 , wherein a diameter of the screw blade attached to the outer circumferential surface of the predetermined portion of the rotating shaft is smaller than a diameter of the screw blade attached to the outer circumferential surface of the rotating shaft other than the predetermined portion.

4. The dryer according to claim 3 , wherein the rotating shaft has a rod-shaped body attached to an outer circumferential surface of a portion of the rotating shaft where the screw blades are not attached, and extending in a radial direction of the rotating shaft.

5. The dryer according to claim 4 , wherein the rod-shaped body is provided on an outer circumferential surface of the predetermined portion of the rotating shaft.

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