Flocculator rotary shaft liquid storage case, flocculator, and manufacturing method of flocculator rotary shaft

Abstract

To provide a flocculator rotary shaft liquid storage case which adjusts a buoyant force of a flocculator rotary shaft to enable easy fine adjustment of a load acting on a bearing and thereby enables adjustment of a balance between the weight of the entire flocculator and the buoyant force even after a length of the flocculator rotary shaft, a size and arrangement of an arm, and a shape and a number of a wing plate etc. are determined.SOLUTION: A flocculator rotary shaft liquid storage case includes: a hollow body part which may be inserted into a flocculator rotary shaft; a bottom part of a plate-like member which covers an opening of one end of the body part; and a lid part which is a plate-like member which covers an opening of the other end of the body part and has a hole capable of introducing water. An outer periphery of the lid part is attached to an inner peripheral surface of the flocculator rotary shaft with water-tightness achieved therebetween.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a flocculator rotating shaft liquid container, a flocculator, and a method for manufacturing a flocculator rotating shaft.

Background Art

[0002] In water purification equipment and the like, a flocculant is added to raw water such as river water, and a flocculation treatment is performed to make turbidity into minute flocs by rapid stirring. The minute flocs that have undergone the flocculation treatment grow into large flocs by repeatedly colliding with each other by applying slow stirring. This process is called floc formation. The raw water containing these minute flocs is slowly stirred by a slow stirrer called a flocculator to grow the flocs into coarse flocs, and the raw water is purified by separating the coarse flocs from the raw water by, for example, sedimentation separation.

[0003] As a flocculator, a configuration is widely used in which a plurality of rotating shafts provided with a large number of paddles are arranged side by side on the same axis in a horizontal direction in a floc formation tank for growing flocs, and these rotating shafts are connected and rotated by a connecting mechanism to slowly stir the raw water with the paddles.

[0004] As such a flocculator, for example, there is one disclosed in Utility Model Document 1. A flocculator is described in which a rotating impeller shaft is configured to be hollow, the hollow portion is sealed, and hollow upper impeller arms are radially provided on the hollow shaft in a sealed state, and the hollow arms are provided with wing plates made of hollow sealing members.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the above-described flocculator, the rotating impeller shaft operated by the driving device, the impeller arm attached thereto, and the impeller plate are each constituted by a hollow sealing member. In this flocculator, in addition to the rotating shaft, the arm and the impeller plate are also hollow sealing members, making each member constituting the flocculator as lightweight as possible. In water, due to the action of buoyancy, the load on the bearing is minimized. To minimize the load on the bearing and minimize the operating load and bending moment, it is necessary to appropriately adjust the balance between the total weight including the constituent members of the flocculator and the buoyancy of each member having a hollow sealed structure. On the other hand, in the flocculator, the length of the rotating shaft, the arrangement and size of the arms, and the shape and number of impeller plates are matters that are appropriately designed according to the required stirring ability and the size of the stirring tank. Therefore, simply constituting the rotating impeller shaft, the impeller arm attached thereto, and the impeller plate with hollow sealing members respectively makes it difficult to adjust the balance between the total weight and the buoyancy of the entire flocculator, which is determined at the final stage of the flocculator design. This is because it is impossible to adjust the buoyancy of the rotating impeller shaft, the impeller arm attached thereto, and the impeller plate after the dimensions of each constituent member of the flocculator are determined.

[0007] Therefore, the present invention has been made in view of the above circumstances, and an object thereof is to provide a liquid container for a flocculator rotating shaft that can easily finely adjust the load acting on the bearing by adjusting the buoyancy of the flocculator rotating shaft and can adjust the balance between the total weight and the buoyancy of the entire flocculator.

Means for Solving the Problems

[0008] As a result of intensive studies on the above problems, the present inventor has found that even after the diameter and length of the hollow flocculator rotating shaft are determined, the present problem can be solved by providing a liquid container capable of adjusting the buoyancy in consideration of the balance with the total weight of the flocculator. That is, the present invention is the following liquid container for a flocculator rotating shaft.

[0009] In order to solve the above problems, the liquid container for the flocculator rotating shaft according to an embodiment of the present invention includes a hollow columnar body portion that can be inserted into the flocculator rotating shaft, a bottom portion of a plate-like member that covers an opening at one end of the body portion, and a plate-like member that covers an opening at the other end of the body portion, and a lid portion having a water-permeable hole, and the outer periphery of the lid portion is attached to the inner peripheral surface of the flocculator rotating shaft with watertightness.

[0010] According to this liquid container for the flocculator rotating shaft, even after the diameter and length of the flocculator rotating shaft are determined, by freely adjusting the volume of the liquid container inserted and fixed inside the flocculator rotating shaft, the buoyancy can be adjusted in consideration of the balance with the total weight of the flocculator. In addition, a lid portion, which is a member that continuously joins the liquid container to the inner peripheral surface of the flocculator rotating shaft with watertightness, can be provided at a position easily reachable from the opening at the end of the flocculator rotating shaft. Thereby, even when the outer periphery of the lid portion is fixed to the inner peripheral surface of the flocculator rotating shaft by welding with watertightness, the welding work can be facilitated.

[0011] Further, as an embodiment of the liquid container for the flocculator rotating shaft of the present invention, it is characterized by including a support portion that supports the body portion. According to this feature, even when the length of the body portion of the liquid container becomes large, the liquid container can be stably temporarily installed on the inner peripheral surface of the flocculator rotating shaft, so that the welding work can also be facilitated.

[0012] As an embodiment of the flocculator of the present invention, it is characterized by including a rotating shaft having a liquid container for the flocculator rotating shaft and a stirring blade fixedly attached to the rotating shaft. According to this feature, even after the diameter and length of the flocculator rotating shaft are determined, by freely adjusting the volume of the liquid container inserted and fixed inside the flocculator rotating shaft, the buoyancy can be adjusted in consideration of the balance with the total weight of the flocculator.

[0013] As an embodiment of the method for manufacturing a flocculator rotating shaft of the present invention, it includes a hollow columnar body portion that can be inserted into the flocculator rotating shaft, a bottom portion of a plate-like member that covers the opening at one end of the body portion, and a lid portion that is a plate-like member covering the opening at the other end of the body portion and has a water-permeable hole, and is characterized in that the outer periphery of the lid portion is attached to the inner peripheral surface of the flocculator rotating shaft with watertightness. According to this method for manufacturing a flocculator rotating shaft, even after the diameter and length of the flocculator rotating shaft are determined, the buoyancy can be adjusted in consideration of the balance with the weight of the entire flocculator. In addition, a lid portion, which is a member for continuously joining a liquid container to the inner peripheral surface of the flocculator rotating shaft with watertightness, can be provided at a position easily reachable from the opening at the end of the flocculator rotating shaft. Thereby, even when the outer periphery of the lid portion is fixed to the inner peripheral surface of the flocculator rotating shaft by welding with watertightness, the welding work can be facilitated.

Effect of the Invention

[0014] According to the present invention, even after the length of the flocculator rotating shaft, the arrangement and size of the arms, the shape and number of the wing plates, etc. are determined, by adjusting the buoyancy of the flocculator rotating shaft, the load acting on the bearing can be easily finely adjusted, and a flocculator rotating shaft liquid container capable of adjusting the balance between the weight and buoyancy of the entire flocculator can be provided.

Brief Explanation of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0016] Hereinafter, the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted. Also, for the sake of illustration, the dimensional ratios in the drawings do not necessarily match those in the description.

[0017] FIG. 1 is a plan view showing the overall outline of a flocculator according to an embodiment of the present invention. As shown in FIG. 1, the flocculator 10 is disposed in a floc formation tank 41 and rotatably supports a rotary shaft 20 having an agitation blade 11 by underwater bearings 43 respectively installed on spaced-apart support bases 42.

[0018] In water purification treatment facilities and the like, a flocculation treatment is performed in which a flocculant is added to raw water such as river water to form flocs from turbidity. In a water purification treatment facility, for example, an inflow channel (not shown) for supplying water to be treated is provided upstream of the floc formation tank 41, and a sedimentation tank (not shown) for sedimentation separation of the formed flocs is provided downstream of the floc formation tank 41. In the flocculation treatment, after adding a flocculant to the raw water and rapidly stirring it, slow stirring is performed to gradually form larger flocs from the turbidity in the raw water, making it easier to remove the flocs in the subsequent treatment. The flocculator is a device for gently stirring the raw water to be treated in order to grow flocs in the floc formation tank. During the operation of slow stirring, the flocculator rotary shaft and the attached arms and paddle plates are in a state of being submerged in the floc formation tank.

[0019] As shown in FIG. 1, the flocculator 10 includes a rotary shaft 20 and an agitation blade 11. The agitation blade 11 includes an arm 13 and a paddle 12. The rotary shaft 20 is capable of rotational drive and rotates around the axis X. The agitation blade 11 is fixed and attached to the outer peripheral surface of the rotary shaft 20 by the arm 13 and rotates in the same direction as the rotation of the rotary shaft 20. When the agitation blade 11 rotates, the surface orthogonal to the rotation direction of the paddle 12 pushes the water to be treated in the floc formation tank 41, thereby performing slow stirring of the water to be treated in the floc formation tank 41.

[0020] 〔First Embodiment〕 FIG. 2 is a cross-sectional view of the liquid container of the first embodiment of the present invention. The rotating shaft 20 of the flocculator 10 is a hollow cylindrical body made of stainless steel or the like extending along the direction of the axis X. The peripheral wall of the cylindrical portion of the rotating shaft 20 is formed as thin as possible within the range where the necessary strength can be maintained. The liquid container 31 of the flocculator rotating shaft according to the first embodiment is provided inside the rotating shaft 20 of the flocculator 10. Therefore, the outer dimensions of the liquid container 31 have dimensions that can be accommodated inside the hollow cylindrical rotating shaft 20.

[0021] The liquid container 31 is a container that stores the water to be treated that has submerged the rotating shaft 20 in the floc formation tank 41 and has been immersed in the rotating shaft 20 when the flocculator 10 is in an operating state. FIG. 2 shows the configuration of the rotating shaft 20 and the liquid container 31 near one end of the rotating shaft 20. A similar configuration is also provided near the other end of the rotating shaft 20 (not shown). The configuration of the liquid container 31 near one end of the rotating shaft 20 shown in FIG. 2 is preferably provided such that its volume is substantially uniform and is substantially symmetric about the central portion in the axial direction X of the rotating shaft 20.

[0022] The configuration of the liquid container 31 of the flocculator rotating shaft will be described. The liquid container 31 includes a cylindrical body portion 33, a bottom portion 34 of a plate-like member that closes the opening at one end of the body portion 33, and a lid portion 32 that is a plate-like member that closes the opening at the other end of the body portion 33. The body portion 33, the bottom portion 34, and the lid portion 32 that constitute the liquid container 31 are desirably made of, for example, the same stainless steel as the rotating shaft 20 in consideration of the weldability between members and the weldability with the rotating shaft 20.

[0023] The bottom portion 34 is fixedly attached so as to close the opening at one end of the cylindrical body portion 33. The bottom portion 34 is fixed by butting against the cross-section of the opening at one end of the cylindrical body portion 33 so as to face it. The fixing method is, for example, butt welding, fillet welding, etc. The lid portion 32 is fixedly attached so as to close the opening at the other end of the cylindrical body portion 33. The lid portion 32 of the plate-like member is butt-joined and fixed so that the cross-section of the opening at the other end of the cylindrical body portion 33 faces it. The fixing method is, for example, butt welding, fillet welding, etc. The lid portion 32 is provided with a water-permeable hole at a position facing the space formed by the inner peripheral surface of the body portion 33, the bottom portion 34, and the lid portion 32.

[0024] The liquid container 31 is provided inside the rotating shaft 20 of the hollow cylindrical body with the bottom portion 34 facing the back side of the rotating shaft 20 and the lid portion 32 facing the opening side. The outer periphery of the lid portion 32 is continuously joined to the inner peripheral surface of the rotating shaft 20 with watertightness by, for example, butt welding, fillet welding, etc. With this structure, the space formed by the inner peripheral surface of the body portion 33, the bottom portion 34, and the lid portion 32 has a structure in which the water to be treated from the outside of the lid portion 32 is conducted through the water-conducting hole 35 of the lid portion 32. As shown in FIG. 2, the water-conducting hole 35 may have a plurality of holes in the lid portion 32, or as shown in the modification of FIG. 4, there may be one hole in the lid portion 32.

[0025] Openings 21 penetrating the peripheral wall are provided on both axial ends of the peripheral wall forming the rotating shaft 20. These openings 21 are arranged so as to be shifted from each other by approximately 180 degrees in the circumferential direction. Then, as the rotating shaft 20 rotates, the water to be treated in the flocculation tank 41 flows from the open opening 21 into the space formed by the inner peripheral surface of the rotating shaft 20, the surface of the lid portion 32 facing one end side of the rotating shaft 20, and the rotating shaft connecting portion 22. Then, the inflowing water to be treated flows into and is stored in the space formed by the inner peripheral surface of the body portion 33, the bottom portion 34, and the lid portion 32 through the water-conducting hole 35 formed in the lid portion 32. When the flocculator 10 is in a stopped state, the water to be treated in the floc formation tank 41 disappears, and the rotating shaft 20 is exposed to the air. In this case, the water to be treated accommodated in the space formed by the inner peripheral surface of the rotating shaft 20, the surface of the lid portion 32 facing one end side of the rotating shaft 20, and the rotating shaft connecting portion 22 flows out from the opening portion 21. Along with this, the water to be treated accommodated in the space formed by the inner peripheral surface of the body portion 33, the bottom portion 34, and the lid portion 32 also flows out through the water guiding hole 35 formed in the lid portion 32.

[0026] The space formed by the inner peripheral surface of the body portion 33, the bottom portion 34, and the lid portion 32, the outer peripheral surface of the body portion 33, the outer surface of the bottom portion 34, the surface of the lid portion 32 extending outside the outer peripheral surface of the body portion 33, and the inner peripheral surface of the rotating shaft 20 is hermetically blocked. The space formed by the outer peripheral surface of the body portion 33, the outer surface of the bottom portion 34, the surface of the lid portion 32 extending outside the outer peripheral surface of the body portion 33, and the inner peripheral surface of the rotating shaft 20 is maintained as a space without the intrusion of the water to be treated from the outside, and this generates buoyancy. The liquid container 31 accommodates the water to be treated inside thereof, thereby balancing the self-weight of the rotating shaft 20 and the stirring blade 11 and the buoyancy acting on the rotating shaft 20, and thus it is possible to adjust the direction of the load acting on the underwater bearing 43.

[0027] The operation and effect of the liquid container 31 of the flocculator rotating shaft according to the first embodiment will be described. By accommodating the treated water inside, the liquid container 31 can adjust the balance between the total self-weight of the flocculator 10 and the buoyancy generated by the space without the intrusion of the water to be treated from the outside formed by the outer peripheral surface of the body portion 33, the outer surface of the bottom portion 34, the surface of the lid portion 32 extending outside the outer peripheral surface of the body portion 33, and the inner peripheral surface of the rotating shaft 20. By adjusting this balance, when the flocculator 10 is in operation and submerged in the floc formation tank 41, the downward load acting on the underwater bearing 43 from the flocculator 10 can be reduced. As a result, the wear caused by the rotation of the rotating shaft 20 occurring in the underwater bearing 43 can be reduced, and thus the replacement frequency of the underwater bearing 43 can be reduced.

[0028] The dimensions of the liquid container 31 can be set independently of the determination of the dimensions of the rotation axis 20 according to the overall design of the flocculator 10. For example, when the overall design of the flocculator 10 is completed and it is necessary to reduce the buoyancy by comparing the self-weight and the possible buoyancy, the dimensions of the liquid container 31 can be set according to the volume corresponding to the buoyancy to be reduced. According to the volume corresponding to the buoyancy to be reduced, by freely changing the dimension along the axis X of the body portion 33, the amount of the water to be treated that can be accommodated in the liquid container 31 can be adjusted. When the amount of the water to be treated to be adjusted is large, the dimension along the axis X of the body portion 33 also becomes large. That is, the position of the bottom portion 34 becomes a place that is considerably deep when viewed from one end of the rotation axis 20. Even in this case, when the liquid container 31 is inserted and installed on the inner peripheral surface of the rotation axis 20, the operation of continuously joining the outer periphery of the lid portion 32 to the inner peripheral surface of the rotation axis 20 can be performed within the reachable range near the opening at one end of the rotation axis 20, so that the workability of the joining operation is improved. For example, when continuously joined with watertightness by butt welding, fillet welding, etc., this welding operation can be easily performed from near the opening at one end of the rotation axis 20.

[0029] 〔Second Embodiment〕 The configuration of the flocculator rotation axis liquid container according to the second embodiment will be described. In the description of the embodiments other than the first embodiment described below, the same or corresponding members as those described in the first embodiment are denoted by the same reference numerals, the description thereof is omitted, and only the different parts will be described.

[0030] FIG. 3 is a cross-sectional view of the liquid container according to the second embodiment of the present invention. The liquid container 31 according to the second embodiment includes a cylindrical body portion 33, a bottom portion 34 which is a plate-like member closing the opening at one end of the body portion 33, and a lid portion 32 which is a plate-like member closing the opening at the other end of the body portion 33, and further includes a spacer 36. The material of each member constituting the liquid container 31 is preferably the same stainless steel or the like as in the first embodiment.

[0031] In the second embodiment, a spacer 36 is provided on the outer periphery of the bottom 34 of the liquid container 31. The spacer 36 functions as a support portion that supports the liquid container 31 so as to keep the distance between the inner peripheral surface of the rotating shaft 20 and the outer peripheral surface of the liquid container 31 constant. FIG. 3 shows an example in which the spacer 36 is provided on the outer periphery of the bottom 34. However, as long as the distance between the inner peripheral surface of the rotating shaft 20 and the outer peripheral surface of the liquid container 31 can be kept constant, it may be provided at a location other than the outer periphery of the bottom 34. When the amount of the water to be treated to be adjusted is large, the dimension along the axis X of the body portion 33 also becomes large. In this case, since the position of the bottom 34 is located quite deep when viewed from one end of the rotating shaft 20, it becomes difficult to install the liquid container 31 in a state where the bottom 34 is properly separated from the inner peripheral surface of the rotating shaft 20 because the bottom 34 may land on the inner peripheral surface of the rotating shaft 20. By providing the spacer 36, the distance between the inner peripheral surface of the rotating shaft 20 and the outer peripheral surface of the liquid container 31 can be kept constant in a separated state. In addition, there is also an effect of making the center of gravity of the rotation around the axis X coincide with the axis X without eccentrically displacing the entire component of the rotating shaft 20.

[0032] As shown in FIG. 3, the spacer 36 may be provided on the outer periphery of the bottom 34, or may be provided at an arbitrary position on the outer peripheral surface of the body portion 33. Further, the spacer 36 may be continuously extended over the entire outer periphery of the bottom 34 or the outer peripheral surface of the body portion 33, or may be provided partially intermittently or discontinuously. Due to the spacer 36, even when the liquid container 31 becomes longer in the direction of the axis X, it can be temporarily installed stably inside the rotating shaft 20, which facilitates the operation of continuously joining the outer periphery of the lid portion 32 to the inner peripheral surface of the rotating shaft 20.

[0033] 〔Other Embodiments〕 As described above, the embodiments of the present invention have been described. However, the present invention is not limited thereto, and can be modified without departing from the technical idea of the invention.

[0034] When the diameter of the rotating shaft 20 is, for example, 250 mm to 600 mm, it is within a range suitable for operation as a flocculator and sufficient buoyancy can be obtained. As another material for the rotating shaft 20, it may be formed by extruding a resin material such as FRP (Fiber Reinforced Plastics). As long as the required strength for the design can be obtained, it has an advantage in terms of weight reduction of the flocculator. Also, it is superior to metal materials in terms of durability in an environment where water splashes. In this case, it is desirable that the material of the liquid container 31 is also a resin material such as the same FRP. For example, a bottom portion 34 processed into a plate shape and a lid portion 32 processed into a plate shape and having water guide holes 35 drilled are mutually joined by adhesive bonding to a barrel portion 33 formed by extruding a resin material such as FRP for manufacturing. The outer periphery of the lid portion 32 is continuously joined in a watertight manner to the inner peripheral surface of the rotating shaft 20 by adhesive bonding.

Explanation of Signs

[0035] 10... Flocculator, 11... Stirring blade, 12... Paddle, 13... Arm, 20... Rotating shaft, 21... Opening, 22... Rotating shaft joint part, 31... Liquid container, 32... Lid part, 33... Barrel part, 34... Bottom part, 35... Water guide hole, 36... Spacer, 41... Flock formation tank, 42... Support base, 43... Submerged bearing

Claims

1. A hollow columnar body that can be inserted inside the flocculator rotating shaft, The bottom of a plate-like member that covers the opening at one end of the body, A lid portion that is a plate-like member covering the opening at the other end of the body and has water-permeable holes, and is provided with: A flocculator rotating shaft liquid container, characterized in that the outer periphery of the lid portion is attached to the inner peripheral surface of the flocculator rotating shaft with watertightness.

2. The flocculator rotating shaft liquid container according to claim 1, further comprising a support portion for supporting the body.

3. A rotating shaft comprising the flocculator rotating shaft liquid container according to claim 1, A flocculator, characterized by comprising a stirring blade fixedly attached to the rotating shaft.

4. A hollow columnar body that can be inserted inside the flocculator rotating shaft, The bottom of a plate-like member that covers the opening at one end of the body, A lid portion that is a plate-like member covering the opening at the other end of the body and has water-permeable holes, and is provided with: A method for manufacturing a flocculator rotating shaft, characterized in that the outer periphery of the lid portion is attached to the inner peripheral surface of the flocculator rotating shaft with watertightness.

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