Waste treatment device

Abstract

To provide a waste treatment device capable of excellently discharging crushed pieces from a discharge port.SOLUTION: A waste treatment device 10 includes a treatment tank 39 in which crushed pieces F of a treatment object containing a polymer P in a water-absorbed state are stored, a discharge port 47 through which the crushed pieces F in the treatment tank 39 are discharged to the outside of the treatment tank 39, and a second nozzle 55B having a plurality of discharge ports 55C through which water is discharged toward the discharge port 47 so as to push the crushed pieces F in the treatment tank 39 into the discharge port 47.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to waste disposal devices. [Background technology]

[0002] Patent Document 1 discloses a technology for performing a water-releasing treatment in which crushed used disposable diapers (hereinafter also referred to as crushed pieces) are agitated with a water-releasing agent in a treatment tank to remove moisture from the polymer contained in the crushed pieces. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-146224 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, when the fragments that have undergone the water-repelling process are discharged from the outlet of the treatment tank, a water flow discharged from the second nozzle in a straight line toward the outlet pushes the fragments into the outlet and discharges them. This water flow has the effect of entraining and carrying away objects that come into contact with the outer surface of the water flow. For example, if the diameter of the water discharged from the second nozzle is very small compared to the diameter of the outlet, the effect of entraining and carrying away objects does not work in positions close to the inner surface of the outlet, away from the outer surface of the water, and the effect of the second nozzle pushing the fragments into the outlet is limited to the area near the center of the outlet. For this reason, a technology that can efficiently discharge fragments from the treatment tank is desired.

[0005] The present disclosure has been made in consideration of the above-described conventional situation, and has as its object to provide a waste disposal device that can satisfactorily discharge crushed pieces from the discharge port. [Means for solving the problem]

[0006] The waste treatment device of the present disclosure comprises a treatment tank in which crushed fragments of the treated material containing a water-absorbing polymer are stored, an outlet for discharging the crushed fragments in the treatment tank to the outside of the treatment tank, and a nozzle having a plurality of outlets for discharging water toward the outlet so as to push the crushed fragments in the treatment tank into the outlet. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a front view showing the configuration of a waste disposal device according to a first embodiment. [Figure 2] FIG. [Figure 3] FIG. 2 is a cross-sectional view taken along line XX in FIG. [Figure 4] FIG. 2 is a cross-sectional plan view of the water-release treatment device. [Figure 5] 5 is a cross-sectional view taken along line YY in FIG. 4. [Figure 6] FIG. 2 is an enlarged cross-sectional side view of the water-release treatment device. [Figure 7] FIG. 4 is an enlarged perspective view showing a second nozzle. [Figure 8] FIG. 10 is a partial enlarged view of the discharge port as seen from the right. [Figure 9] FIG. [Figure 10] 10 is a flowchart showing the control of the water-repelling process and the dewatering process. [Figure 11] FIG. 10 is a perspective view showing the configuration of a nozzle in another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] <Embodiment 1> A first embodiment of a waste disposal device 10 according to the present disclosure will be described below with reference to Figures 1 to 10. In the following description, the up-down direction is defined as the direction shown in Figure 1, as upward and downward. The left-right direction is defined as the direction shown in Figure 1, as left and right. The front-rear direction is defined as the direction shown in Figures 2, 3, and 4, as downward and upward, as backward.

[0009] The waste disposal device 10 is a device that performs processing to dispose of used disposable diapers D, which are objects to be disposed of. The waste disposal device 10 is installed in a care facility or the like where multiple used disposable diapers D are generated irregularly at different times.

[0010] The disposable diaper D to be treated is a sheet material S such as nonwoven fabric that contains a super absorbent polymer P (SAP, hereinafter simply referred to as polymer P) and pulp. The sheet material S has a surface layer made of polypropylene nonwoven fabric or the like and a waterproof material made of a resin material such as polyethylene. The pulp and polymer P are sandwiched between the surface layer and the waterproof material. The pulp and polymer P have water absorption properties to absorb water from waste such as human waste and water retention properties to maintain the water in an absorbed state. The sheet material S contains a resin material such as polypropylene or polyethylene whose density is lower than that of water. The particle size of the polymer P before absorbing water is 150 to 600 μm, which is denser than water. The polymer P swells and becomes gel-like after absorbing water, and the particle size of the polymer P in the water-absorbed state is 600 μm to 4 mm. The objects to be treated in the waste treatment device 10 are sanitary products. Sanitary products include disposable diapers, napkins, pet wipes, etc.

[0011] The disposal of used disposable diapers D is carried out through a crushing process in which the disposable diapers D are crushed, a water-releasing process in which water is separated from the water-absorbing polymer P, and a dehydration process. In the dehydration process, waste liquid such as the treatment liquid T used in the water-releasing process and water separated from the polymer P is separated from solid matter such as the sheet material S and the polymer P.

[0012] The water-repelling treatment step is carried out using a water-releasing agent R that reduces the water retention capacity of the polymer P that has absorbed water. Specifically, crushed pieces F of disposable diapers D are immersed in a treatment solution T in which the water-releasing agent R is dissolved in water. The crushed pieces F contain polymer P in a water-absorbed state. In this embodiment, calcium chloride containing divalent metal ions is used as an example of the water-releasing agent R. By reacting the water-releasing agent R with the polymer P, water is separated from the polymer P that has absorbed water. The polymer P from which water has been separated loses its water absorption capacity and enters an irreversible state in which it cannot absorb water again. Even if a used disposable diaper D contains polymer P that has not absorbed water, the polymer P will lose its water absorption capacity.

[0013] [Configuration of waste treatment device] As shown in Figure 1, the waste treatment device 10 is configured to include an input section 12, a control section 58, a deodorizing device 21, a crushing device 25, a water-releasing treatment device 38, and a dehydration device 60. The waste treatment device 10 has a vertically long box-shaped housing 13 that is shared by the input section 12, the crushing device 25, and the water-releasing treatment device 38. The crushing device 25 is disposed below the input section 12, the water-releasing treatment device 38 is disposed below the crushing device 25, and the dehydration device 60 is disposed below the water-releasing treatment device 38.

[0014] [Input section configuration] The insertion section 12 is box-shaped with an open bottom. The interior of the insertion section 12 is an insertion space 14 into which used disposable diapers D are inserted. In the first embodiment, the insertion section 12 is provided with a first insertion opening 15. The first insertion opening 15 is formed in the right wall portion constituting the housing 13. The first insertion opening 15 is provided with a first lid 16 that can be opened and closed from the outside of the insertion section 12. The first lid 16 has a central axis 16A that extends horizontally (i.e., in the front-to-rear direction) along its lower edge. The central axis 16A is supported by the housing 13. The first lid 16 can rotate outward around the central axis 16A to change its posture between an upright position V and a laid-down position L.

[0015] A closure portion 22 is provided within the insertion portion 12 so as to cover the first insertion opening 15 from the inside. The closure portion 22 is formed, for example, in the shape of a flat plate, from flexible rubber or synthetic resin. A plurality of slits are formed in the closure portion 22, extending from slightly below the upper end of the closure portion 22 to the lower end. A plurality of rectangular portions 22A, the upper ends of which are connected to each other by the slits, are formed in the closure portion 22. The closure portion 22 is attached to the insertion portion 12 so that its upper end is aligned with the upper edge of the first insertion opening 15. For example, when disposable diapers D are inserted into the insertion portion 12 from the first insertion opening 15, the rectangular portions 22A of the closure portion 22 are pushed outward into the insertion portion 12. After the disposable diapers D have been inserted into the insertion portion 12, the rectangular portions 22A return to their original positions so as to close the first insertion opening 15.

[0016] The disposable diapers D can be inserted into the insertion space 14 through the first insertion opening 15. At this time, the first lid 16 is manually changed from the upright position V to the laid-down position L, opening the first insertion opening 15. The user inserts the disposable diapers D into the insertion section 12 through the first insertion opening 15 and the closing section 22. At this time, the first lid 16 maintains its own position in the laid-down position L. This prevents moisture and other contaminants adhering to the inner surface of the first lid 16 (i.e., the surface located within the insertion section 12 in the upright position V) from flowing to the floor. The disposable diapers D are inserted into the insertion section 12 along the inner surface of the first lid 16. Therefore, when inserting the disposable diapers D through the first insertion opening 15, the position of the disposable diapers D relative to the shredding device 25 is likely to be stable. After inserting the disposable diapers D, the user manually changes the first lid 16 from the laid-down state L to the standing state V, thereby closing the first insertion opening 15.

[0017] The input section 12 is provided with an input sensor 20 that detects when a disposable diaper D is input into the input space 14 through the first input port 15. The input sensor 20 transmits a detection signal to the control unit 58 each time a disposable diaper D is input. The control unit 58 is electrically connected to an operation unit, which is not shown. The user of the waste disposal device 10 can start or stop the operation of the waste disposal device 10 by operating this operation unit.

[0018] 2, a first opening 12A, a second opening 12B, and a third opening 12C are formed on the upper surface of the insertion unit 12. The third opening 12C is arranged along the right side edge of the upper surface of the insertion unit 12, which is close to the first insertion opening 15 in the left-right direction. The first opening 12A and the second opening 12B are arranged along the left side edge of the upper surface of the insertion unit 12, which is away from the first insertion opening 15 in the left-right direction, with the third opening 12C sandwiched between them.

[0019] [Controller configuration] The control unit 58 is configured as, for example, a microcomputer. A detection signal is input to the control unit 58 from the input sensor 20. Based on the detection signal from the input sensor 20, an operation on an operation unit (not shown), etc., the control unit 58 can control various operations such as the operation of the air intake units 21D and 21G, the driving of the crushing motor 29, the water supply operation of the first water supply unit 34 and the second water supply unit 54, the operation of the agitation motor 50, the supply operation of the water-repellent agent R by the water-repellent agent supply unit 56, the opening and closing operation of the on-off valve 65, and the operation of the dewatering motor 68, which is a drive unit.

[0020] [Configuration of deodorizing equipment] The deodorizing device 21 is provided on the upper surface of the input section 12. The deodorizing device 21 includes a first deodorizing device 21A and a second deodorizing device 21B. The first deodorizing device 21A and the second deodorizing device 21B are arranged side by side in the left-right direction on the upper surface of the input section 12. Specifically, the second deodorizing device 21B is arranged along the right side edge of the upper surface of the input section 12, which is close to the first input opening 15 in the left-right direction. The first deodorizing device 21A is arranged along the left side edge of the upper surface of the input section 12, which is far from the first input opening 15, with the second deodorizing device 21B sandwiched between them in the left-right direction. The first deodorizing device 21A includes a case 21C, an intake section 21D, and a deodorizing section main body 21E. The case 21C is box-shaped with a closed top and an open bottom. The case 21C is attached so that its bottom abuts against the upper surface of the input section 12. The case 21C allows the first opening 12A and the second opening 12B of the insertion portion 12 to communicate with each other.

[0021] For example, a known axial fan or the like is used for intake section 21D. Air intake section 21D takes in air from the bottom surface and blows out air from the top surface. Air intake section 21D is electrically connected to control section 58. Air intake section 21D is attached to the top surface of input section 12 so as to cover first opening 12A with its bottom surface. Air intake section 21D is located inside case 21C. Air intake section 21D takes in air from input section 12 through first opening 12A.

[0022] The deodorizing unit main body 21E uses a so-called deodorizing filter made of, for example, nonwoven fabric with activated carbon attached thereto. The deodorizing unit main body 21E is arranged so that air blown from the upper surface (i.e., the surface that blows air) of the intake unit 21D is blown onto the front side of the deodorizing unit main body 21E. Specifically, the deodorizing unit main body 21E is arranged in the case 21C so as to separate the side communicating with the first opening 12A from the side communicating with the second opening 12B. The intake unit 21D sucks air from inside the input unit 12 from the lower surface and blows it toward the deodorizing unit main body 21E from the upper surface. The deodorizing unit main body 21E deodorizes the air blown from the upper surface of the intake unit 21D. The deodorized air is returned to the input unit 12 via the second opening 12B. The second opening 12B is a circulation port that returns the air deodorized by the first deodorizing device 21A into the input section 12. The first deodorizing device 21A mainly deodorizes the air in the left area of ​​the input section 12 by circulating the air in the front-to-rear direction.

[0023] The second deodorizing device 21B has a case 21F, an intake section 21G, and a deodorizing section main body 21H. The case 21F is box-shaped with a closed top and a partially open bottom and rear. The case 21F is attached so that its bottom abuts against the top surface of the input section 12. The rear surface of the case 21F is open. The case 21F is placed on the top surface of the input section 12 so that the bottom surface of the case 21F overlaps above the third opening 12C of the input section 12.

[0024] Similar to intake section 21D, intake section 21G uses a known axial fan or the like. Intake section 21G takes in air from the bottom surface and blows out air from the top surface. Intake section 21G is electrically connected to control section 58. Intake section 21G is attached to the top surface of input section 12 so that the bottom surface of intake section 21G covers third opening 12C. Intake section 21G is located inside case 21F. Intake section 21G takes in air from input section 12 through third opening 12C.

[0025] Like the deodorizing unit main body 21E, the deodorizing unit main body 21H uses a so-called deodorizing filter made of, for example, nonwoven fabric with activated carbon attached. The deodorizing unit main body 21H is disposed to close the open rear surface of the case 21F. Air blown from the upper surface (i.e., the blowing surface) of the air intake unit 21G is blown onto the front surface of the deodorizing unit main body 21H. The deodorizing unit main body 21H discharges deodorized air to the outside from the rear surface. At this time, the air Ex discharged to the outside is discharged in a rearward direction different from the right side where the first input port 15 is formed. This prevents the deodorized air from being discharged toward a user positioned opposite the first input port 15, thereby making the waste disposal device 10 less likely to cause the user to perceive odors. The air intake unit 21G draws air from the input port 12 from the bottom surface and blows it toward the deodorizing unit main body 21H from the top surface. That is, the second deodorizing device 21B sucks in the odor generated from the disposable diapers D put into the putting-in section 12 from the right side of the putting-in section 12, deodorizes it, and discharges the deodorized air to the outside.

[0026] [Crushing equipment configuration] The crushing device 25 is a device for crushing disposable diapers D, which are objects to be crushed, that have been inserted into the insertion section 12. As shown in FIGS. 1 and 3, the crushing device 25 has a peripheral wall 26, a pair of left and right crushing members 28, and a first water supply section 34. The peripheral wall 26 constitutes the housing 13 and is connected to the lower end of the wall of the insertion section 12. A crushing space 27 surrounded by the peripheral wall 26 is formed inside the crushing device 25. The crushing space 27 is in communication with the insertion space 14. A pair of crushing members 28 are housed within the crushing space 27.

[0027] The pair of crushing members 28 are cylindrical in shape with their axes facing forward and backward. Each crushing member 28 has a rotating shaft 30 that is driven to rotate by a crushing motor 29. The driving of the crushing motor 29 is controlled by a control unit 58. The pair of crushing members 28 are arranged side by side with the axes of the rotating shafts 30 at the same height. Multiple shearing blades 31 are formed on the outer periphery of each crushing member 28. Each shearing blade 31 is disc-shaped and concentric with the rotating shaft 30. The maximum outer diameter of the shearing blade 31 is larger than the outer diameter of the rotating shaft 30. The multiple shearing blades 31 are arranged at regular intervals in the axial direction of the rotating shaft 30 (see Figure 3). The width dimension of each shearing blade 31 in the axial direction is the same as or slightly smaller than the distance between adjacent shearing blades 31.

[0028] The outer peripheral surface of each shear blade 31 is saw-toothed with multiple protrusions 32 arranged at a constant pitch in the circumferential direction. The protrusions 32 protrude obliquely relative to the radial direction of the shear blade 31. The protrusions 32 protrude forward in the rotation direction of the protrusions 32. Recesses 33 are formed between adjacent protrusions 32 in the circumferential direction on the outer periphery of the shear blade 31. The multiple recesses 33 are arranged at intervals in the circumferential direction on the outer periphery of the shear blade 31. The shapes of the protrusions 32 and recesses 33 of one shear blade 31 are bilaterally symmetrical to the shapes of the protrusions 32 and recesses 33 of the other shear blade 31.

[0029] As shown in Fig. 3, the multiple shear blades 31 formed on one crushing member 28 and the multiple shear blades 31 formed on the other crushing member 28 are arranged alternately in the axial direction of the rotation shaft 30. In the front view of the waste disposal device 10 shown in Fig. 1, the rotation direction of one crushing member 28 and the rotation direction of the other crushing member 28 are opposite to each other. In the region where one shear blade 31 and the other shear blade 31 overlap in the axial direction, both the one shear blade 31 and the other shear blade 31 are displaced downward as the crushing member 28 rotates.

[0030] Between adjacent shear blades 31 in the axial direction, there is a minimum necessary clearance that allows the crushing members 28 to rotate smoothly without interfering with each other and prevents crushed pieces F of the disposable diaper D from getting caught between the shear blades 31. The clearance between the shear blades 31 is, for example, 40 μm or more. Between the outer periphery of the shear blade 31 of one crushing member 28 and the outer circumferential surface of the rotating shaft 30 of the other crushing member 28, there is a minimum necessary clearance that does not interfere with the rotation of both crushing members 28. The clearance between the shear blade 31 and the rotating shaft 30 is, for example, 100 μm or more.

[0031] The portions of the shearing blades 31 opposite to the portions alternately arranged in the axial direction are displaced upward as the crushing member 28 rotates. The portions of the shearing blades 31 that move upward are arranged along the inner surface of the peripheral wall 26. A minimum necessary clearance is provided between the shearing blades 31 and the peripheral wall 26 so that the shearing blades 31 can rotate smoothly without interfering with the peripheral wall 26 and so that crushed pieces F of the disposable diaper D do not get in between the shearing blades 31 and the peripheral wall 26. The clearance between the shearing blades 31 and the peripheral wall 26 is, for example, 100 μm or more.

[0032] The maximum outer diameter of one crushing member 28 and the maximum outer diameter of the other crushing member 28 are the same. The maximum outer diameter of the crushing member 28 is 120 mm, and the rotation speed of the crushing member 28 is 9 rpm. Therefore, the peripheral speed of the outer periphery of the crushing member 28, i.e., the shear blade 31, is 0.057 m / s. The peripheral speed of the outer periphery of the crushing member 28, i.e., the shear blade 31, is preferably 0.1 m / s or less. The width of one shear blade 31, i.e., the dimension in the axial direction of the rotation shaft 30, is preferably 6 mm or more and 30 mm or less, and more preferably 10 mm or more and 12 mm or less. The width of the shear blade 31 is preferably larger than 4 mm, which is the particle size of the polymer P in a water-absorbed state. When the disposable diaper D is crushed in the crushing device 25, it becomes crushed pieces F. The crushed pieces F include the polymer P in a water-absorbed state, and strip-shaped crushed pieces B having the same width as the width of the shearing blade 31 (that is, a predetermined width).

[0033] As shown in FIG. 1, the first water supply unit 34 is disposed at a position on the peripheral wall 26 above the crushing members 28. Water is discharged from the crushing space nozzle 35 of the first water supply unit 34 into the crushing space 27. The water discharged from the crushing space nozzle 35 rains down on the crushing members 28 from above. The water rained down on the crushing members 28 passes through the gaps between the shearing blades 31, the gaps between the shearing blades 31 and the rotating shaft 30, and the gaps between the shearing blades 31 and the peripheral wall 26, and flows down below the crushing members 28. The water supply operation of the first water supply unit 34 is controlled by the control unit 58.

[0034] [Configuration of water release treatment device] As shown in Figure 1, the water-repelling treatment device 38 includes a treatment tank 39, an agitator 48, a second water supply section 54, and a water-repelling agent supply section 56. The treatment tank 39 is box-shaped, and the right-hand region of the top of the treatment tank 39 is open. The interior of the treatment tank 39 is a treatment space for performing water-repelling treatment. The open right-hand region of the top of the treatment tank 39 is connected to the lower end of the peripheral wall section 26 of the crushing device 25. The crushing space 27 and the space inside the treatment tank 39 are vertically connected.

[0035] As shown in Figures 4 and 5, the bottom surface 41 of the treatment tank 39 is composed of a first inclined surface 42 which is a flat surface and a second inclined surface 43 which is also a flat surface. The bottom surface 41 of the treatment tank 39 is bent in a valley shape at a boundary line 44 between the first inclined surface 42 and the second inclined surface 43. The first inclined surface 42 constitutes the front region of the bottom surface 41. The first inclined surface 42 is located below the opening region of the upper surface of the treatment tank 39, i.e., below the pair of crushing members 28. The second inclined surface 43 constitutes the rear region of the bottom surface 41. The second inclined surface 43 is located in a region offset rearward from the pair of crushing members 28.

[0036] As shown in FIG. 5 , the left-right lower edge of the first inclined surface 42 and the left-right lower edge of the second inclined surface 43 are joined at an obtuse angle. The first inclined surface 42 slopes downward toward the rear and toward the left. The second inclined surface 43 slopes downward toward the front and toward the left. A boundary 44 between the first inclined surface 42 and the second inclined surface 43 slopes downward toward an outlet 47 (described later). The front-to-rear dimension of the first inclined surface 42 is greater than the front-to-rear dimension of the second inclined surface 43. In a side view, the inclination angle β of the second inclined surface 43 with respect to the horizontal direction H is greater than the inclination angle α of the first inclined surface 42 with respect to the horizontal direction H. The inclination angle α of the first inclined surface 42 is 15°. The inclination angle β of the second inclined surface 43 is 45° or less.

[0037] A circular discharge port 47 is provided on the left side wall 46, which is a side wall constituting the treatment tank 39. As shown in FIG. 1, the upstream end of a discharge channel 47A is connected to the discharge port 47. The downstream end of the discharge channel 47A is connected to the upper end of an inlet 62 of a dehydration device 60 (described later). The discharge channel 47A has a downward slope throughout its entire length. The discharge channel 47A extends at an angle γ obliquely downward as it extends away from the discharge port 47. As shown in FIG. 6, the inclination angle γ of a first central axis L1 at the upper side of the discharge channel 47A relative to the horizontal direction H is approximately 15 degrees. Specifically, the first central axis L1 is defined as a straight line connecting the center Ce1 of the discharge port 47 and the center Ce2 at the downstream end of the discharge channel 47A, which extends obliquely downward from the discharge port 47. An on-off valve 65 for opening and closing the discharge channel 47A is provided along the discharge channel 47A. As the on-off valve 65, for example, an electric ball valve is used.

[0038] The on-off valve 65 opens after the water-repelling process is completed in the treatment tank 39. Then, the crushed fragments F, polymer P, and treatment liquid T in the treatment tank 39 are discharged from the treatment tank 39 through the discharge port 47 due to their own weight and the water pressure of the treatment liquid T in the treatment tank 39, and flow downstream through the discharge path 47A to the inlet section 62 of the dehydration device 60, which will be described later. When the on-off valve 65 closes, the crushed fragments F and treatment liquid T in the treatment tank 39 do not flow downstream to the dehydration device 60, but remain in the treatment tank 39. The opening and closing operation of the on-off valve 65 is controlled by the control unit 58.

[0039] The crushed pieces F and the strip-shaped crushed pieces B include lightweight fragments of the sheet material S, such as resin material, which has a density lower than that of water. The height dimension of the opening area of ​​the discharge outlet 47, i.e., the diameter dimension of the discharge outlet 47, is 50 mm or more. This dimension setting is based on the assumption that the maximum width dimension of the crushed pieces F sheared by the shearing blades 31 is approximately 30 mm.

[0040] The discharge outlet 47 opens to the right into the treatment tank 39, and is located at the lowest position on the bottom surface 41. Specifically, the discharge outlet 47 is located at the lower end of the left edge of the first inclined surface 42 and the second inclined surface 43, and is located at a position corresponding to the boundary line 44 in the front-to-rear direction (see FIG. 4). Therefore, the bottom surface 41 of the treatment tank 39 is inclined downward toward the discharge outlet 47.

[0041] The lowest end of the discharge port 47 is located at a height close to the lowest end of the bottom surface 41 of the treatment tank 39. The maximum depth of the treatment tank 39 is the height dimension from the lowest end (i.e., the left end) of the boundary line 44 on the bottom surface 41 of the treatment tank 39 to the top end of the treatment tank 39 (i.e., the bottom end of the crushing device 25) (see FIG. 5). The maximum depth of the treatment tank 39 is a dimension within three times the height from the bottom surface 41 of the treatment tank 39 to the top end of the discharge port 47. This dimension setting makes it possible to keep the water level of the treatment liquid T stored in the treatment tank 39 relatively low, thereby ensuring a wide area for the liquid surface Ls of the treatment liquid T. In the first embodiment, the left-right dimension and the front-to-back dimension of the treatment tank 39 are greater than the maximum depth dimension of the treatment tank 39.

[0042] An agitator 48 is provided on the bottom surface 41. As shown in FIG. 4, in a plan view of the water-repellent treatment device 38 seen from above, the agitator 48 is arranged only in an area of ​​the bottom surface 41 that corresponds to the first inclined surface 42. In the front-to-rear direction, the agitator 48 is arranged rearward of the center of the first inclined surface 42, i.e., in a position biased toward the side closer to the discharge outlet 47 and the boundary line 44. In the left-to-right direction, the agitator 48 is arranged leftward of the center of the first inclined surface 42, i.e., in a position biased toward the side closer to the discharge outlet 47. The agitator 48 is driven to rotate by an agitator motor 50 having a drive shaft 49 extending in the vertical direction (see FIG. 1).

[0043] The agitating member 48 has a disk-shaped main body 51 concentric with the drive shaft 49 and a plurality of ribs 52 that rotate integrally with the main body 51. As shown in FIG. 6, the main body 51 is parallel to the first inclined surface 42. A clearance is provided between the underside of the main body 51 and the first inclined surface 42, which allows the agitating member 48 to rotate smoothly and prevents crushed pieces F of disposable diapers D from getting caught. The clearance between the agitating member 48 and the first inclined surface 42 is approximately 10 mm. The plurality of ribs 52 protrude from the surface of the main body 51 and extend radially from the center of rotation of the main body 51. The plurality of ribs 52 are arranged radially on the upper surface of the main body 51 (see FIG. 4). The agitating member 48 is rotatably provided within the treatment tank 39.

[0044] The drive of the agitation motor 50 is controlled by the control unit 58. During the water-repelling process, the agitation member 48 is driven to rotate alternately in a forward direction (one direction) and a reverse direction (the other direction) by the control unit 58. The forward direction is the counterclockwise direction in FIG. 4, and the reverse direction is the clockwise direction in FIG. 4. After the water-repelling process, the polymer P and crushed fragments F including the band-shaped crushed fragments B in the treatment tank 39, and the treatment liquid T are discharged from the discharge port 47. As shown in FIG. 4, in a plan view, the streamline 47L of the discharge flow at the discharge port 47 is perpendicular to the left side wall 46 on which the discharge port 47 is formed and is parallel to the boundary line 44. Of the tangents to the outer periphery of the agitation member 48, the tangent perpendicular to the left side wall 46 is parallel and close to the streamline 47L of the discharge flow. In other words, the discharge port 47 exists on the extension line of the tangent line that is parallel to the boundary line 44 among the tangent lines that contact the outer periphery of the agitator 48. Therefore, of the flows generated by the rotation of the agitator 48 during discharge, the streamline 48L of the flow heading toward the discharge port 47 is parallel to and close to the streamline 47L of the discharge flow at the discharge port 47.

[0045] During the water-repelling process, the agitating member 48 rotates through a single forward rotation of 60°. During the water-repelling process, the agitating member 48 rotates through a single reverse rotation of 45°, which is smaller than the angle of rotation in the forward direction. In both the forward and reverse directions, the rotation angle is preferably 10° or more and 120° or less. The outer diameter of the agitating member 48 is 120 mm. The time required for one forward rotation is 0.3 seconds, and the time required for one reverse rotation is 0.2 seconds. The peripheral speed of the agitating member 48 is 200 mm / s. The peripheral speed of the agitating member 48 during the water-repelling process can be adjusted within a range of 100 to 500 mm / s. After the water-repelling process is completed, the peripheral speed of the outer periphery of the stirring member 48 is adjusted to 600 mm / s or more from the time when water supply into the treatment tank 39 begins until the crushed fragments F and treatment liquid T in the treatment tank 39 are discharged and the solid crushed fragments F are recovered from the dewatering device 60.

[0046] The second water supply section 54 has a first nozzle 55A attached to the treatment tank 39 and a second nozzle 55B. The first nozzle 55A and the second nozzle 55B face the inside of the treatment tank 39. The first nozzle 55A and the second nozzle 55B are provided on the right side wall section 53 that rises from the bottom surface 41 and faces the left side wall section 46. The first nozzle 55A is positioned so as to spray water toward the agitator 48. The first nozzle 55A sprays water in a fan shape that spreads horizontally (i.e., in the front-to-rear direction).

[0047] The second nozzle 55B is disposed so as to discharge water toward the outlet 47. Specifically, the second nozzle 55B is attached to the right side wall 53 directly opposite the left side wall 46 in which the outlet 47 is formed. As shown in FIGS. 5 and 6, the second nozzle 55B is disposed above the outlet 47. As shown in FIG. 7, the second nozzle 55B has a plurality of outlets 55C. Each outlet 55C is circular. In the first embodiment, the diameter of each outlet 55C is, for example, 1 mm. The plurality of outlets 55C are disposed at equal intervals on an imaginary circumference C. The central axes of the outlets 55C are parallel to one another. In the first embodiment, eight outlets 55C are formed in the second nozzle 55B. The outlets 55C are parallel to one another and discharge water in a straight line. In other words, the second nozzle 55B is a so-called direct injection nozzle. A cross section of water discharged from each outlet 55C in the discharge direction Vo, which is perpendicular to the discharge direction Vo at a position any distance away from each outlet 55C, is the water discharge area Sa1. The water discharge area Sa1 can be defined as a plurality of water discharge areas Sa1 lined up at any distance from each outlet 55C in the discharge direction Vo. Here, a straight line passing through the center Ce3 of each of the plurality of water discharge areas Sa1 lined up in the discharge direction Vo from each outlet 55C is defined as a second central axis L2.

[0048] As shown in FIG. 6, the second nozzle 55B discharges water from each outlet 55C at an obliquely downward angle toward the discharge port 47. The discharge direction Vo of each outlet 55C is toward the lower inner edge of the discharge port 47. For example, the inclination angle δ of the second central axis L2 of the outlet 55C with respect to the horizontal direction H is approximately 30 degrees. The inclination angle δ (30 degrees) of the discharge direction Vo (second central axis L2) of the outlet 55C with respect to the horizontal direction H is greater than the inclination angle γ (15 degrees) of the first central axis L1 of the discharge channel 47A with respect to the horizontal direction H. The second central axis L2 intersects with the first central axis L1 at an imaginary point Pf, which is a predetermined point on the discharge channel 47A within the treatment tank 39, and passes below the first central axis L1 between the imaginary point Pf and the discharge port 47. The discharge direction Vo of each discharge outlet 55C is set to be parallel to each other and point downward from the center Ce1 of the discharge outlet 47 (in embodiment 1, the lower end of the discharge outlet 47) (see the arrow parallel to the second central axis L2 in Figure 6).

[0049] When the crushed fragments F, polymer P, and treatment liquid T are contained in the treatment tank 39, the second nozzle 55B is positioned above the liquid level Ls. The water discharged from the discharge port 55C flows parallel to the second central axis L2 above the liquid level Ls of the treatment liquid T. Then, below the liquid level Ls of the treatment liquid T (i.e., within the treatment liquid T), the water discharged from each discharge port 55C deviates upward from the second central axis L2 and flows through the treatment liquid T while entraining the crushed fragments F, gradually thickening its flow, passing around the center Ce1 of the discharge port 47 and flowing into the discharge path 47A (see the gradually thickening arrows in FIG. 6). When the discharge outlet 47 is viewed from the front (right), the water W discharged from each discharge outlet 55C flows into the discharge outlet 47 along the inner edge of the discharge outlet 47 and at equal intervals concentrically about the center Ce1 of the discharge outlet 47 (see FIG. 8). In this way, each discharge outlet 55C discharges water toward the discharge outlet 47 so as to push the crushed fragments F in the treatment tank 39 into the discharge outlet 47.

[0050] The first water discharge area A1 (see FIG. 4) from which the first nozzle 55A discharges water is wider than the second water discharge area A2 (see FIG. 5) from which the second nozzle 55B discharges water when the treatment liquid T and the crushed fragments F are not contained in the treatment tank 39. The discharge and stopping of water from the first nozzle 55A and the second nozzle 55B is controlled by the control unit 58.

[0051] As shown in Fig. 1, a water-repellent agent supply unit 56 is attached to the treatment tank 39. The water-repellent agent supply unit 56 supplies a predetermined amount of the above-mentioned water-repellent agent R into the treatment tank 39. The supply operation and amount of the water-repellent agent R are controlled by a control unit 58.

[0052] [Configuration of dehydration device] The dehydrator 60 is a so-called screw press dehydrator used in the waste treatment device 10. The dehydrator 60 has an inlet section 62, a dehydrator 61, an outlet section 63, and a water collection section 69. The inlet section 62 is cylindrical, and the downstream end of the discharge channel 47A is connected to the upper end thereof. The crushed pieces F and treated liquid T in the treatment tank 39 are transferred into the dehydrator 61 by passing through the discharge port 47, the discharge channel 47A, the on-off valve 65, and the inlet section 62. The inlet section 62 is connected to the discharge port 47 of the treatment tank 39 via the discharge channel 47A. The crushed pieces F flow into the inlet section 62.

[0053] The dehydrator 61 is connected to the lower end of the inlet section 62. As shown in FIG. 9, a screen section 66 and a screw 67 are housed within the dehydrator 61. The screen section 66 is cylindrical with its axis oriented in the left-right direction. The screen section 66 is formed with, for example, a plurality of water-passing holes extending elongatedly in the axial direction (not shown). The width of the water-passing holes (width in a direction perpendicular to the axial direction) is, for example, 300 μm. It is desirable that the width of these water-passing holes be smaller than the particle size of the polymer P in a water-released state after separation from the water-absorbed state. The internal space of the screen section 66 is a transfer space 66S for transferring the crushed fragments F. The upstream end F1 of the transfer space 66S is connected to the lower end of the inlet section 62, and the downstream end F2 of the transfer space 66S is connected to the upper end of the outlet section 63.

[0054] The screw 67 has a shaft portion 67A and screw blades 67B spirally protruding from the outer periphery of the shaft portion 67A. For example, the distance between the blades of the screw blades 67B in the axial direction narrows toward the downstream end F2 (see FIG. 9). The shaft diameter of the shaft portion 67A increases toward the downstream end F2 (see FIG. 9). The cross-sectional area of ​​the transfer space 66S perpendicular to the axis decreases toward the downstream end F2 (not shown). The shaft portion 67A and the screw blades 67B are disposed within the inlet portion 62 and the screen portion 66 and are driven to rotate by a dehydration motor 68, which serves as a drive unit. The screw blades 67B extend in the direction of the central axis of the screen portion 66. A gap is provided around the entire circumference between the outer periphery of the screw blades 67B located within the screen portion 66 and the inner circumferential surface 66A of the screen portion 66.

[0055] As shown in Fig. 9, outflow section 63 is disposed at the right end of dehydrator 61 and has a cylindrical shape that protrudes downward from dehydrator 61. A collection port 71 that opens downward is formed at the lower end of outflow section 63.

[0056] The water collection section 69 is formed in an area of ​​the underside of the dehydrator 61 corresponding to the screen section 66. The water collection section 69 opens upward toward the transfer space 66S over the entire range from the upstream end F1 to the downstream end F2 of the transfer space 66S. A drain outlet 70 is formed at the lowest position of the water collection section 69. While the screw 67 transfers the crushed fragments F and the treatment liquid T in the transfer space 66S, the waste liquid containing the treatment liquid T flows down through the water passage holes in the screen section 66 to the outside of the transfer space 66S. The waste liquid that flows down to the outside of the transfer space 66S is collected in the water collection section 69 and discharged from the drain outlet 70 to the sewer or the like via a drain pipe (not shown).

[0057] The axis of the screw 67 is the same as the axis of the screen section 66 and is parallel to the transport direction of the screw 67. As shown in Figure 1, in a side view, the axis of the screw 67 is inclined so that, of the two transport direction end portions of the screw 67, the downstream end is higher than the upstream end. The direction in which the screw 67 transports the crushed fragments F within the transport space 66S is the direction in which the crushed fragments F are lifted up against gravity.

[0058] The control unit 58 controls the timing of the start of the water-releasing process depending on the amount of disposable diapers D put into the putting-in section 12 and the time elapsed since the disposable diapers D were put in. The control unit 58 executes transport control to control the water-releasing process time in the water-releasing treatment device 38, the timing of transferring the crushed pieces F and treatment liquid T after the water-releasing process to the dewatering device 60, and the rotation direction of the screw 67 of the dewatering device 60.

[0059] [Control of crushing process by the control unit] A used disposable diaper D is placed into the input space 14. When the control unit 58 detects that a used disposable diaper D has been placed into the input space 14, it starts the operation of the deodorizing device 21. Then, the control unit 58 starts the shredding motor 29. After being placed, the inserted disposable diaper D is immediately shredded by a pair of shearing blades 31, and falls into the treatment tank 39 as shredded pieces F including strip-shaped shredded pieces B having a predetermined width. The shredded pieces F contain polymer P in a water-absorbed state. In this way, the treatment tank 39 contains shredded pieces F of the disposable diaper D including polymer P in a water-absorbed state.

[0060] The crushing member 28 may rotate continuously or only while crushing the disposable diaper D. The amount of water supplied from the first water supply unit 34 is only the amount necessary to crush and release water from one disposable diaper D. The maximum particle size of the water-absorbed polymer P is approximately 4 mm, while the width of the shearing blades 31 of the crushing member 28 is 6 mm or more, so there is no risk of the water-absorbed polymer P being sheared by the shearing blades 31. The peripheral speed of the shearing blades 31 is low, at 0.1 m / s or less, so this speed setting can also prevent the water-absorbed polymer P from being crushed. The width of the shearing blades 31 is 30 mm or less, so the sheet material S of the disposable diaper D can be sheared into small strips. The crushed fragments F are hooked by the protrusions 32 on the periphery of the shearing blades 31 and fitted into the recesses 33, allowing them to reliably fall into the treatment tank 39 below the crushing member 28.

[0061] [Control of water release and dehydration processes by the control unit] The control of the water-repelling process and the dewatering process by the control unit 58 will be described with reference to the flowchart of Figure 10. After performing the crushing process, the control unit 58 starts the rotation of the agitator 48 (step S20). Next, a water-repelling agent R made of calcium chloride is introduced into the treatment tank 39, and water supply from the first water supply unit 34 is started (step S21). The introduction of the water-repelling agent R and the water supply from the first water supply unit 34 are preferably started simultaneously. The introduction of the water-repelling agent R and the water supply from the first water supply unit 34 may also be performed with a time lag. The water supplied from the first water supply unit 34 washes the crushing members 28 and flows down into the treatment tank 39. After a predetermined amount of water has been supplied, the water supply from the first water supply unit 34 is stopped (step S22).

[0062] The amount of water-repelling agent R added is controlled by the control unit 58 so that it is an appropriate amount based on the number of disposable diapers D to be subjected to water-repelling treatment, i.e., based on the mass. When the water-repelling agent R dissolves in the water supplied to the treatment tank 39, it becomes a treatment liquid T for water-repelling treatment. In the first embodiment, the water-repelling agent R and water are supplied separately to the treatment tank 39. Alternatively, the treatment liquid T, in which the water-repelling agent R has been dissolved in water in advance, may be supplied to the treatment tank 39. The water-repelling treatment is a treatment in which the water-retaining ability of the polymer P of the crushed pieces F immersed in the treatment liquid T is reduced by the water-repelling agent R in the water-repelling liquid, thereby separating water from the polymer P. The reaction rate of the water-repelling treatment increases with the amount of water-repelling agent R, i.e., the concentration of the treatment liquid T.

[0063] The agitating member 48 alternately rotates in a forward direction, which is the counterclockwise direction in Figure 4, and in a reverse direction, which is the clockwise direction. Therefore, even if there is a pile of crushed fragments F on the agitating member 48 when the agitating member 48 starts to rotate, the pile of crushed fragments F will be broken down by the agitating member 48 rotating in both forward and reverse directions, and the crushed fragments F will be dispersed into the processing liquid T. Because the peripheral speed of the outer periphery of the agitating member 48 is slower than 500 mm / s, the crushed fragments F and processing liquid T will not be scattered radially.

[0064] The rotation angle of the agitator 48 in the forward direction is 60°, while the rotation angle in the reverse direction is 45°. Due to this difference in the forward and reverse rotation angles, the agitator 48 rotates intermittently in the forward direction. Due to the intermittent rotation of the agitator 48 in the forward direction, the treatment liquid T and the crushed fragments F flow as a spiral in the region of the treatment tank 39 far from the agitator 48. Turbulence occurs near the agitator 48, causing the treatment liquid T and the crushed fragments F to move slightly. These movements cause the water-repelling agent R to come into contact with the polymer P, and the water-repelling process progresses.

[0065] The control unit 58 determines whether a predetermined water-repelling treatment time has elapsed since the start of the water-repelling treatment (step S23). When the predetermined water-repelling treatment time has elapsed, the water-repelling treatment is terminated. The predetermined water-repelling treatment time is shorter than the time required for water to be completely separated from the polymer P. The particle size and mass of the polymer P at the time when the water-repelling treatment time has elapsed are larger than the particle size and mass of the polymer P when water-repelling is completely completed.

[0066] When the water-repelling process is completed, the control unit 58 starts supplying water from the first water supply unit 34 and the second water supply unit 54 to the treatment tank 39 (step S24). This water supply reduces the concentration of the treatment solution T in the treatment tank 39, and the progress of the water-repelling process by the water-repelling agent R stops. During this time, the polymer P is in an irreversible state.

[0067] When the water supply to treatment tank 39 has progressed to a certain extent, the water supply to treatment tank 39 is stopped (step S25). At this time, the water level in treatment tank 39 is above outlet 47 and below first nozzle 55A and second nozzle 55B. Thereafter, control unit 58 rotates agitator 48 in the forward direction to start rotation of screw 67 (step S26), and then opens on-off valve 65 (step S27). At this time, control unit 58 starts executing transport control to rotate screw 67 in the forward direction.

[0068] When the on-off valve 65 is opened, the treatment liquid T and the fragments F in the treatment tank 39 are discharged from the discharge port 47. At the beginning of the process of discharging the treatment liquid T and the fragments F from the discharge port 47, the agitator 48 continues to rotate in the forward direction. Because the viscosity of the treatment liquid T is reduced by the water supply from the first water supply section 34 and the second water supply section 54, flow resistance is low and the treatment liquid T is discharged smoothly from the discharge port 47. The direction of the discharge flow at the discharge port 47 is parallel to the boundary line 44 between the first inclined surface 42 and the second inclined surface 43. Of the vortex flow generated by the agitator 48, a portion of the flow in the region adjacent to the boundary line 44 flows parallel to the boundary line 44 toward the discharge port 47. Therefore, the flow velocity of the discharge flow at the discharge port 47 is increased.

[0069] As the on-off valve 65 opens, water is temporarily discharged from the first nozzle 55A and the second nozzle 55B of the second water supply unit 54 (step S28). This discharge of water increases the flow rate of the discharge flow from the discharge port 47. At this time, the water discharged from the second nozzle 55B hits the liquid surface Ls and travels through the treatment liquid T toward the discharge port 47, as shown in FIG. 6. When the water discharged from the second nozzle 55B hits the liquid surface Ls, its direction of travel changes upward relative to the second central axis L2 and travels through the treatment liquid T, gradually increasing the outer diameter of the flow while entraining the fragments F (see the gradually increasing arrows in FIG. 6). In this way, the water discharged from each discharge port 55C of the second nozzle 55B and reaching the discharge port 47 flows into the discharge port 47 along the inner edge of the discharge port 47. Specifically, the water W discharged from each outlet 55C flows into the outlet 47 so as to be equally spaced concentrically about the center Ce1 of the outlet 47 (see FIGS. 7 and 8). In this way, the treatment liquid T and the crushed fragments F are pushed into the outlet 47 by the water W discharged from the second nozzle 55B and are efficiently discharged from the treatment tank 39.

[0070] The first nozzle 55A begins to eject water as the fragments F begin to be discharged from the outlet 47. The first nozzle 55A ejects water in a fan shape. This agitates the treatment liquid T and fragments F in the treatment tank 39 by rotating vertically, mixing them evenly, and facilitating their discharge from the outlet 47. Specifically, this vertical rotation of the treatment liquid T and fragments F occurs when the water is ejected from the first nozzle 55A, causing the upper sides of the treatment liquid T and fragments F stored in the treatment tank 39 to flow leftward and sink downward, and then to flow rightward along the bottom surface 41 of the treatment tank 39 and rise upward. In other words, the first nozzle 55A ejects water in a manner that pushes the fragments F floating on the water surface into the water and disperses the fragments F in the treatment tank 39.

[0071] After the discharge of the processing liquid T and the fragments F from the discharge port 47 has started, step S28 is executed and, after a predetermined time, the discharge of water from the first nozzle 55A and the second nozzle 55B is temporarily stopped for a predetermined time (step S29). This makes it possible to reduce the water supply from the second water supply unit 54, thereby saving water.

[0072] Step S29 is executed, and the on-off valve 65 is closed after a predetermined time (step S30). Step S30 is executed, and the on-off valve 65 is opened after a predetermined time (step S31). Furthermore, as the discharge of the processing liquid T and the fragments F from the discharge port 47 progresses, the operation of the agitator 48 changes from rotating in the forward direction to rotating in short increments alternately in the forward and reverse directions (step S32). This shakes off the fragments F accumulated on the upper surface of the agitator 48. In other words, the agitator 48 starts rotating in the forward direction and then rotates alternately in both the forward and reverse directions. At this time, the agitator 48 rotates at a larger angle in the reverse direction than in the forward direction. As a result, the agitator 48 rotates intermittently in the reverse direction. Furthermore, at this time, the discharge of water from the first nozzle 55A and the second nozzle 55B is resumed (step S33). Because the agitator 48 rotates intermittently in the opposite direction, the water ejected from the first nozzle 55A is sprayed evenly over the entire upper surface of the agitator 48. At this time, the fragments F accumulated on the upper surface of the agitator 48 are peeled off from the upper surface of the agitator 48 and drawn toward the outlet 47. In other words, the first nozzle 55A ejects water to draw the fragments F toward the outlet 47. Furthermore, as the discharge of the fragments F and the treatment liquid T from the treatment tank 39 progresses and the liquid level Ls in the treatment tank 39 decreases, when the liquid level Ls reaches the lower end of the outlet 47, the water ejected from the second nozzle 55B is ejected toward the lower end of the outlet 47 without moving upward relative to the second central axis L2 (see the arrow parallel to the second central axis L2 in FIG. 6). In this way, when the liquid level Ls in the treatment tank 39 becomes lower, the water ejected from the second nozzle 55B is ejected toward the lower end of the discharge outlet 47, so that the crushed fragments F that have accumulated at the bottom of the treatment tank 39, particularly those containing polymer P which has a higher density than water, can be pushed toward the discharge outlet 47.

[0073] After step S33 is performed and a predetermined time has elapsed, the discharge of the processing solution T and the fragments F from the outlet 47 progresses, and when there are no more fragments F above the agitator 48, the discharge of water from the first nozzle 55A and the second nozzle 55B is stopped, and the operation of the agitator 48 is changed from alternating small rotations in the forward and reverse directions to a rotation in the forward direction (step S34). In other words, the first nozzle 55A continues to discharge water until there are no more fragments F above the agitator 48. The halt in the discharge of water from the first nozzle 55A for the predetermined time (before steps S29 to S33 are performed) occurs between the start of the discharge of the fragments F from the outlet 47 and the end of the fragments F above the agitator 48. The timing at which the discharge of water from the second nozzle 55B ends may be later than the timing at which the discharge of water from the first nozzle 55A ends. This ensures that the processing solution T and the fragments F are discharged from the outlet 47. When the dewatering devices 60 are configured to be spaced apart and not adjacent to each other, delaying the timing at which the discharge of water from the second nozzle 55B ends relative to the timing at which the discharge of water from the first nozzle 55A ends can be expected to have the effect of flushing the inside of the discharge path 47A so that the crushed fragments F discharged from the discharge port 47 do not clog the discharge path 47A. Step S34 is executed, and after a predetermined time, the on-off valve 65 is closed (step S35).

[0074] The treatment liquid T and crushed pieces F discharged from the discharge outlet 47 are transported into the dehydrator 61 through the discharge path 47A. The control unit 58 starts executing transport control in step S26, and continues rotating the screw 67 in the forward direction. Within the dehydrator 61, the band-shaped crushed pieces B and crushed pieces F containing the treatment liquid T are pushed by the screw blades 67B of the screw 67 and compressed in the axial direction, causing the moisture within the band-shaped crushed pieces B and crushed pieces F to seep out. The seeped moisture passes through the water passage holes in the screen section 66 and is discharged from the drain outlet 70. The crushed pieces F containing the polymer P pushed by the screw 67 are recovered from the recovery port 71.

[0075] Within the screen section 66, some of the polymer P comes into contact with the inner peripheral surface 66A of the screen section 66, raising concerns that it may pass through the water-passing holes in the screen section 66. However, in the crushing device 25, the peripheral speed of the shear blades 31 is set to a low speed of 0.1 m / s, and the width of the shear blades 31 is set to 6 mm or more, which is larger than the particle size of the polymer P in the water-absorbing state. Therefore, the polymer P in the water-absorbing state is not sheared, and falls into the treatment tank 39 of the water-repelling treatment device 38 as large particles. Furthermore, in the water-repelling treatment device 38, the water-repelling treatment is completed before the water is completely separated from the polymer P, so the particle size of the polymer P is maintained at a certain size. Therefore, there is no risk of the polymer P passing through the water-passing holes in the screen section 66.

[0076] When all of the processing liquid T and fragments F have been processed (Yes in step S36), the control unit 58 stops the rotation of the agitator 48 (step S37), stops the execution of transport control, and stops the rotation of the screw 67 (step S38). The deodorizing device 21 also stops operating. This completes the water-repelling process and the dehydration process. If, in step S36, all of the processing liquid T and fragments F have not been processed (No in step S36), the process proceeds to step S31.

[0077] In the waste disposal device 10, the total amount of water discharged from the first water supply section 34 and the second water supply section 54 when treating one disposable diaper D can be set to a predetermined amount. For example, in the case of a disposable diaper D containing relatively small amounts of sheet material S, pulp, and polymer P, the total amount of water discharged from the first water supply section 34 and the second water supply section 54 can be set to approximately 10 liters. In contrast, in the case of a disposable diaper D containing relatively large amounts of sheet material S, pulp, and polymer P, the total amount of water discharged from the first water supply section 34 and the second water supply section 54 can be set to approximately 20 liters.

[0078] According to the embodiment configured as above, the following effects are achieved.

[0079] The waste treatment device 10 of the present disclosure includes a treatment tank 39 that contains crushed fragments F of the material to be treated, including the polymer P in a water-absorbed state; an outlet 47 that discharges the crushed fragments F from the treatment tank 39 to the outside of the treatment tank 39; and a second nozzle 55B having multiple outlets 55C that discharge water toward the outlet 47 so as to push the crushed fragments F from the treatment tank 39 into the outlet 47. With this configuration, the water is discharged from the multiple outlets 55C, which makes it easier for the water to spread as it moves away from the second nozzle 55B, and the area that has the effect of entraining the crushed fragments F in contact with the outer periphery of the discharged water tends to expand in a direction perpendicular to the water discharge direction Vo. This makes it possible to entrain the crushed fragments F even near the inner edge of the outlet 47, allowing the crushed fragments F from the treatment tank 39 to be efficiently entrained and pushed into the outlet 47.

[0080] Each outlet 55C of the waste disposal device 10 of the present disclosure discharges water in a straight line. With this configuration, since water is discharged in a straight line, the discharged water can be easily delivered to a targeted position.

[0081] The water discharged from each outlet 55C of the waste treatment device 10 of the present disclosure flows along the inner edge of the discharge outlet 47. With this configuration, the action of entraining the broken fragments F in the water discharged from each outlet 55C can be generated evenly throughout the discharge outlet 47.

[0082] The discharge direction Vo of each discharge port 55C of the waste disposal device 10 of the present disclosure is directed toward the lower inner edge of the discharge port 47. With this configuration, the action of entraining the broken fragments F in the water discharged from each discharge port 55C can be generated evenly throughout the discharge port 47.

[0083] The water discharged from each outlet 55C of the wastewater treatment device 10 of the present disclosure flows into the outlet 47 so as to be equally spaced concentrically about the center Ce1 of the outlet 47. With this configuration, the water discharged from each outlet 55C does not interfere with the action of engulfing the fragments F, and this action can occur evenly throughout the outlet 47.

[0084] The discharge outlet 47 of the wastewater treatment device 10 of the present disclosure is provided in the left side wall 46 of the treatment tank 39, and the multiple discharge outlets 55C discharge water at an angle downward toward the discharge outlet 47, and the discharge direction Vo of all of the multiple discharge outlets 55C faces downward from the center Ce1 of the discharge outlet 47. When the treatment tank 39 is filled with the treatment liquid T and the liquid level Ls of the treatment liquid T is located above the upper end of the discharge outlet 47, the water discharged from each discharge outlet 55C changes its flow direction upward within the treatment liquid T. Therefore, with this configuration, even if the flow direction of the water within the treatment liquid T changes upward, the water can be discharged without departing from the discharge outlet 47.

[0085] In the wastewater treatment device 10 of the present disclosure, a line connecting the center Ce1 of the discharge outlet 47 and the center Ce2 at the downstream end of the discharge channel 47A extending linearly from the discharge outlet 47 is a first central axis L1 of the discharge channel 47A, the discharge directions Vo of the discharge outlets 55C are parallel to each other, and the inclination angle δ of the discharge directions Vo with respect to the horizontal direction H is greater than the inclination angle γ of the first central axis L1 with respect to the horizontal direction H. This configuration enables the discharge outlet 55C to discharge water from above the liquid level Ls of the treatment liquid T even when the treatment tank 39 is filled with the treatment liquid T and the discharge outlet 47 is blocked by the treatment liquid T.

[0086] In the wastewater treatment device 10 of the present disclosure, a cross section of water discharged from each outlet 55C in the discharge direction Vo that is perpendicular to the discharge direction Vo is a water discharge area Sa1, and a second central axis L2 passing through the center Ce3 of each of the multiple water discharge areas Sa1 aligned in the discharge direction Vo from each outlet 55C intersects with the first central axis L1 at an imaginary point Pf in the treatment tank 39 and passes below the first central axis L1 of the discharge path 47A between the imaginary point Pf and the discharge outlet 47. When the treatment tank 39 is filled with the treatment liquid T and the liquid level Ls of the treatment liquid T is located above the discharge outlet 47, the discharged water changes its flow direction upward within the treatment liquid T. Therefore, with this configuration, even if the flow direction of the water changes upward within the treatment liquid T, the water can be discharged without departing from the discharge outlet 47.

[0087] The present disclosure is not limited to the first embodiment described above with reference to the drawings, and the following embodiments are also included within the technical scope of the crushing device of the present disclosure.

[0088] (1) In the first embodiment, the stirring member is provided on the bottom surface of the treatment tank, but this is not limiting and the stirring member may be provided on another surface of the treatment tank. (2) In the first embodiment, the first nozzle and the second nozzle eject water at the same timing. However, the present invention is not limited to this, and the first nozzle and the second nozzle may eject water at different timings. (3) In the first embodiment, the water is ejected from the first nozzle in a fan-like shape. However, this is not limiting, and the water may be ejected in a cone-like shape. Furthermore, a plurality of second nozzles that eject water in a straight line may be arranged side by side. (4) In the first embodiment, calcium chloride is used as the synergist. However, other agents containing Ca or Mg may be used, such as calcium acetate, magnesium chloride, water-soluble alkaline earth metal salts of magnesium nitrate, citric acid, etc. (5) The synergist may be either solid or liquid. When the synergist is liquid, a synergist supply unit is used, which has a storage tank for storing the synergist and a pump for extracting the synergist from the storage tank and sending it to the housing. (6) The number of outlets in the nozzle is not limited to that in the first embodiment. (7) The arrangement of the outlets in the nozzle may be changed depending on the outer shape of the outlet. For example, if the outer shape of the outlet is rectangular, the nozzle 155 may be formed with outlets 155C that discharge water at equal intervals in a straight line relative to the outlet, as shown in Fig. 11. In this case, each of the water discharge areas Sa2, which are lined up at any distance from each outlet 155C in the discharge direction Vo, has a strip-like shape, and the second central axis L2 passes through the center of the linearly lined-up outlets 155C and passes through the center Ce4 of each of the strip-shaped water discharge areas Sa2 lined up in the discharge direction Vo from each outlet 155C. (8) Unlike the first embodiment, the discharge direction of more than half of the plurality of discharge ports may be configured to face downward from the center of the discharge ports. (9) The inclination angle of the discharge direction of the discharge outlet relative to the horizontal direction and the inclination angle of the first central axis of the discharge passage relative to the horizontal direction are not limited to those in embodiment 1, as long as the inclination angle of the discharge direction relative to the horizontal direction is greater than the inclination angle of the first central axis of the discharge passage relative to the horizontal direction. (10) Unlike the first embodiment, the outlets may be arranged so that they are spaced equally apart from one another in a concentric pattern around the center of the outlet. This configuration also allows the water discharged from each outlet to entrain the debris evenly throughout the outlet.

[0089] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and the scope of the present disclosure is not limited to the embodiments disclosed herein. [Explanation of symbols]

[0090] 10... Wastewater treatment device, 39... Treatment tank, 46... Left side wall (side wall), 47... Discharge outlet, 47A... Discharge channel, 55B, 155... Second nozzle (nozzle), 55C, 155C... Discharge outlet, Ce1... Center of discharge outlet, D... Used disposable diaper (material to be treated), F... Crushed pieces, H... Horizontal direction, L1... First central axis of discharge channel, L2... Second central axis of discharge outlet, Pf... Imaginary point (predetermined point), Sa1, Sa2... Water discharge area, Vo... Discharge direction

Claims

1. a treatment tank for accommodating crushed pieces of the object to be treated, the crushed pieces including the polymer in a water-absorbed state; a discharge port for discharging the crushed pieces in the treatment tank to the outside of the treatment tank; a nozzle having a plurality of outlets that ejects water toward the outlet so as to push the crushed pieces in the treatment tank into the outlet; A waste disposal device comprising:

2. The waste disposal device according to claim 1 , wherein each of the outlets discharges water in a straight line.

3. The waste disposal device according to claim 2 , wherein the water discharged from each of the outlets flows along an inner edge of the outlet.

4. The waste disposal device according to claim 2 , wherein the discharge direction of each of the discharge ports is toward an inner edge of the discharge port.

5. The waste disposal device according to claim 3 , wherein the water discharged from each of the outlets flows into the outlets so as to be equally spaced concentrically about the center of the outlet.

6. The waste disposal device according to claim 3 , wherein the discharge ports are arranged concentrically about the center of the discharge port at equal intervals and discharge in the direction of the discharge port.

7. The discharge port is provided in a side wall of the treatment tank, The plurality of outlets are inclined obliquely downward toward the discharge outlet to discharge water, The waste disposal device according to claim 1 , wherein the discharge directions of at least half of the plurality of discharge ports are directed downward relative to the centers of the discharge ports.

8. a line connecting a center of the discharge port and a center at a downstream end of the discharge passage extending linearly from the discharge port is a first central axis of the discharge passage; 8. The waste disposal device according to claim 7, wherein the discharge directions of the discharge ports are parallel to each other, and the angle of inclination of the discharge directions with respect to the horizontal direction is greater than the angle of inclination of the first central axis with respect to the horizontal direction.

9. a cross section of the water discharged from each of the discharge ports in the discharge direction that is perpendicular to the discharge direction is a water discharge area; A waste treatment device as described in claim 8, wherein a second central axis passing through the center of each of the plurality of water discharge areas arranged in the discharge direction from each of the discharge outlets intersects with the first central axis at a predetermined point within the treatment tank and passes below the first central axis between the predetermined point and the discharge outlet.

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