Slurry processing apparatus

Abstract

The present invention provides a slurry processing device that uses a rubber, plate-shaped rake for long-term use. [Solution] A slurry processing apparatus comprising a processing tank for settling solid matter contained in a slurry, and a rake unit 25 that moves along the bottom surface of the processing tank and scrapes the settled solid matter with a rubber, plate-shaped rake 25a to discharge it to the outside, wherein the rake unit 25 has a pair of clamp plates 25f, 25r that sandwich the rake 25a from the front and back, and bolts 25b and nuts 25c that tighten the clamp plates 25f, 25r together in a direction that sandwiches the rake 25a, and at least one of the clamp plates 25f is provided with a convex grip portion 25i that presses the rake 25a on the surface that contacts the rake 25a.

Description

Technical Field

[0003] , , ,

[0001] The present invention relates to a slurry treatment device for treating slurry such as concrete slurry generated when washing raw concrete (hereinafter referred to as "remaining concrete") obtained by kneading at least cement, water, gravel, and sand remaining in the mixing drum of a mixer truck.

Background Art

[0002] The remaining concrete remaining in the mixing drum of the mixer truck is taken back to the raw concrete factory and processed by a remaining concrete processing device. As described in, for example, Patent Document 1 (see FIG. 12), a conventional remaining concrete processing device includes a cleaning device 100 for cleaning the remaining concrete, an aggregate classifier 101 + cyclone 102 for separating gravel G and sand S from the concrete slurry sent out as cleaning drainage from the cleaning device 100, and a processing water tank 102 for settling solids containing cement from the slurry after separating gravel G and sand S by the aggregate classifier 101 or the like to separate solid and liquid, a slurry processing device 103 such as a filter press for dehydrating the solids settled in the processing water tank 102, and a supernatant water tank 104 for storing the supernatant water of the processing water tank 102. The gravel G, sand S, and the supernatant water of the supernatant water tank 104 are reused, and the solids (so-called cake) dehydrated by the dehydrator 103 are treated as industrial waste.

[0003] Instead of the above filter press, a slurry treatment device is provided in a processing water tank for settling solids contained in the slurry, with a rake unit that can endlessly circulate around the bottom surface of the processing water tank by chain drive, and the solids settled by rubber plate-shaped rakes constituting the rake unit are scraped and discharged to the outside (see Patent Document 2). The rake unit of this slurry treatment device has a pair of clamp plates that sandwich the plate-shaped rake from the front and back, and bolts and nuts for tightening the clamp plates in the direction of sandwiching the rake. A plurality of through holes for passing the bolts are provided in a horizontal row in the rubber rake. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2001-327805 [Patent Document 2] Japanese Patent Publication No. 2019-18455 [Overview of the project] [Problems that the invention aims to solve]

[0005] The rake unit endlessly circulates along a raking path that moves along the bottom of the treated water tank and scrapes up solid matter with the rake, and a return path that moves away from the bottom of the treated water tank and in the opposite direction. During its rotation, the rake, as it moves along the raking path, is subjected to a force that pulls it out of the clamp plate due to frictional resistance between its lower edge and the solid material accumulated on its bottom surface, as well as resistance to pushing the solid material. It is then released from this force as it moves along the return path. Therefore, the rake, while clamped between the plates, is subjected to repeated stress over long periods of time, being strongly pulled along the raking path and released along the return path. However, although the rake is a flat plate of uniform thickness, multiple through holes for bolts are provided in a horizontal line, so the cross-sectional area of ​​the part that crosses these through holes is smaller than the cross-sectional area of ​​other parts. Consequently, it is more strongly affected by the stress caused by the repeated tension and release described above compared to other parts, which led to problems such as cracks forming in that area and eventually fracture.

[0006] The present invention has been made in view of the above, and its object is to provide a slurry processing device that allows a rubber, plate-shaped rake to be used for a long period of time. [Means for solving the problem]

[0007] [Claim 1] To achieve the above objectives, the present invention A treatment tank for settling solid matter contained in the slurry, A slurry processing apparatus having a rake unit that moves along the bottom surface of the processing tank and scrapes the settled solid material with a rubber, plate-shaped rake to discharge it to the outside, The aforementioned rake unit is, A pair of clamping plates that sandwich the rake from the front and back, The clamp plates are fastened together with bolts and nuts in a direction that sandwiches the rake, The present invention provides a slurry processing device comprising a convex grip portion that compresses the rake on the surface of at least one of the clamp plates that is in contact with the rake. In this slurry processing device, the rake is locked by the pressure of the grip portion provided on the clamp plate, so stress from repeated tension and release is less likely to be transmitted to the area with the through hole. As a result, the risk of breakage of the rubber plate-shaped rake is reduced, allowing the slurry processing device to be used stably over a long period of time.

[0008] [Claim 2] The present invention provides a slurry processing apparatus according to claim 1, wherein the grip portion is provided with a number of elongated ribs of a predetermined length that are inclined at an angle of θ° with respect to the lower edge of the clamp plate, and elongated ribs of a predetermined length that are also inclined at an angle of -θ°. In this slurry processing device, the inclination of the ribs in the grip section distributes the tensile force acting on the rake in the raking path both along the ribs and perpendicular to them. Furthermore, by setting the inclination of the ribs to θ° and -θ°, that is, mirror-image inclination in the left-right direction, the distributed forces act in directions that cancel each other out, thereby reducing the risk of breakage of the rubber rake.

[0009] [Claim 3] The slurry processing apparatus according to claim 2 is provided, wherein the ribs of the grip portion are provided protruding from the intersection of a diagonal grid formed by a virtual parallel diagonal line inclined at θ° with respect to the lower edge of the clamp plate and a virtual parallel diagonal line inclined at -θ°. In such a slurry processing apparatus, the ribs of the grip portion are regularly arranged on the intersections of the virtual diagonal grids, so that the tensile force acting on the rake in the lifting path is more evenly distributed. As a result, the breakage risk of the rubber rake can be further reduced.

[0010] [Claim 4] Provide the slurry processing apparatus according to claim 2 or 3, wherein the θ° is about 45°. In such a slurry processing apparatus, since the downward tensile force acting on the rake in the lifting path is evenly distributed in the direction along the rib of the grip portion and the direction orthogonal thereto, the breakage risk of the rubber rake can be reduced.

[0011] Note that the virtual parallel diagonal lines and diagonal grids described above are convenient concepts for specifying the inclination and arrangement of the ribs, and of course, they are not embodied in the actual clamp plate, nor do they need to appear at any stage of the manufacturing process.

Advantages of the Invention

[0012] As described above, according to the present invention, it is possible to provide a slurry processing apparatus that can use a rubber plate-shaped rake over a long period of time.

Brief Description of the Drawings

[0013] [Figure 1] It is a plan view of the residue processing apparatus showing the flow path with imaginary lines. [Figure 2] It is a plan view of the residue processing apparatus showing the parts other than the flow path with imaginary lines [Figure 3] It is a partially enlarged plan view of FIG. 1 showing the charging section (constant supply device) and the aggregate separation section (gravel separation section and sand separation section). [Figure 4] It is a sectional view taken along line A-A of FIG. 3. [Figure 5] It is a plan view of the solid-liquid separation section. [Figure 6] It is a longitudinal front view of the solid-liquid separation section. [Figure 7] It is an enlarged view of the main part of FIG. 6 showing the rake unit. [Figure 8] It is a sectional view taken along line B-B of FIG. 6. [Figure 9] It is a perspective view of a main part of a conveyor chain. [Figure 10-1] It is an exploded perspective view of a rake unit. [[ID=,9]] [Figure 10-2] (a) is a front view with the middle part of a clamp plate omitted, and (b) is a front view with the middle part of a clamp plate showing another form omitted. [Figure 11] It is a flowchart showing an overview of a residual concrete processing device. [Figure 12] It is a flowchart showing an overview of a conventional residual concrete processing device.

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [1. Residual Concrete Processing Device] The residual concrete processing device processes raw concrete (hereinafter referred to as "residual concrete") obtained by kneading at least cement, water, gravel, and sand remaining in the mixing drum D of the mixer truck M. As shown in the plan view of FIG. 1 and the flowchart of FIG. 11, an input unit 1 that inputs the residual concrete in the mixing drum D and further adds water to the residual concrete to form concrete slurry, an aggregate separation unit 2 that separates gravel and sand from the concrete slurry of the input unit 1, and a solid-liquid separation unit 4 that puts the concrete slurry after separating gravel and sand in the aggregate separation unit 2 into a treatment water tank 3 to precipitate solids containing cement. The solid-liquid separation unit 4 corresponds to the slurry processing device of the present invention.

[0015] [2. Input Unit] As shown in the plan view of FIG. 1, the input unit 1 includes a residual concrete storage tank 1a that discharges the residual concrete in the mixing drum D from the chute C of the mixer truck M and temporarily stores it, and a quantitative supply device 1b that receives the residual concrete accumulated in the residual concrete storage tank 1a and transfers it to the next aggregate separation unit 2. The quantitative supply device 1b is a so-called hopper-screw conveyor consisting of a hopper 5 with an open top and a bottom that slopes toward the center, and a screw 6 provided at the lower end of the hopper 5. Water is added to the remaining concrete in the hopper 5 that is fed in from the remaining concrete storage tank 1a, and the mixture is kneaded by the screw 6, thereby adjusting it into a highly fluid concrete slurry before transferring it to the next aggregate separation section 2. Furthermore, the process of adding water to the remaining concrete to create a highly fluid concrete slurry does not necessarily have to be performed in the hopper 5 of the quantitative supply device 1b; it may also be performed in the mixing drum D of the mixer truck M. In that case, the concrete slurry can be directly fed from the mixing drum D into the hopper 5 of the quantitative supply device 1b. Therefore, the input unit 1 of the present invention may be configured as a combination of a residual concrete storage tank 1a and a quantitative supply device 1b, as in the embodiment, or it may be configured as a quantitative supply device 1b alone.

[0016] [3. Aggregate Separation Section] As shown in the flow diagram of Figure 11, the aggregate separation unit 2 is generally composed of a gravel separation unit 2a that separates gravel from the concrete slurry supplied from the input unit 1, a recovery tank 2b that receives the concrete slurry after the gravel has been separated in the gravel separation unit 2a, a sand separation unit 2c that separates sand from the concrete slurry in the recovery tank 2b, a recovery / sand separation channel 2d connecting the recovery tank 2b and the sand separation unit 2c, a pump 2e connected to the end of the recovery / sand separation channel 2d that sends the concrete slurry from the recovery tank 2b to the gravel separation unit 2a, a return channel 2f connecting the sand separation unit 2c and the recovery tank 2b, and a sand separation / input channel 2g connecting the sand separation unit 2c and the input unit 1.

[0017] [3-1. Gravel Separation Section] The gravel separation unit 2a uses a vibrating screen system in which a screen 8 is vibrated by a vibrator 7. Concrete slurry supplied onto the screen 8 from the quantitative supply device 1b of the input unit 1 passes through to the recovery tank 2b below, while gravel G of a predetermined particle size or larger contained in the concrete slurry is moved laterally by the vibration of the screen 8 and transported to a conveying belt conveyor 9 (see Figures 1, 3, and 4). The gravel G on the belt conveyor 9 is then transported to a recovered gravel storage area 10, where it is recovered by a power shovel or the like and reused as a resource.

[0018] [3-2. Recovery Tank] The recovery tank 2b is roughly bowl-shaped with an open top, and the pump 2e is located in the square-shaped, tapered bottom 2h. This recovery tank 2b is located below the sieve 8 of the gravel separation section 2a and stores the concrete slurry that has passed through the sieve 8. The sand contained in the concrete slurry is collected around the pump 2e at the bottom 2h of the recovery tank 2b. The pump 2e is suspended from above the recovery tank 2b by a suspension means such as a crane (not shown), and its vertical position, i.e., the suction position, can be adjusted as needed by driving the crane or the like.

[0019] [3-3. Sand separation department] The sand separation unit 2c is, for example, a screw classifier that separates sand from the concrete slurry after gravel separation, and is generally composed of a hopper-shaped classification tank 13 equipped with a distribution header 12 for flow rate adjustment at the top, as shown in Figures 3 and 4, and a screw conveyor 14 provided at the bottom of the classification tank 13 with a conveying direction diagonally upward.

[0020] The end of the recovery / sand separation channel 2d is connected to the distribution header 12 of the sand separation section 2c. Therefore, when the pump 2e is operated, the concrete slurry accumulated in the recovery tank 2b is sent to the distribution header 12 through the recovery / sand separation channel 2d, and flows down from the distribution header 12 to the classification tank 13. Overflow troughs 15 are provided on both sides of the upper outer surface of the classification tank 13. The concrete slurry near the liquid surface that flows into the classification tank 13 flows into the overflow troughs 15 and is then sent to the solid-liquid separation section 4 through the classification / solid-liquid separation channel 16. Meanwhile, the sand S contained in the concrete slurry settles in the classification tank 13 and is transported diagonally upward by the screw conveyor 14, rising above the liquid level and finally falling into the recovered sand storage area 17. The sand S that falls into the recovered sand storage area 17 is then collected by a power shovel or the like and reused as a resource.

[0021] [3-4. Return channel] The return channel 2f connects the sand separation section 2c and the recovery tank 2b. Its starting end is connected to the lowest point of the bottom 11 of the classification tank 13, and its terminal end is open to the inside of the recovery tank 2b. Therefore, a portion of the concrete slurry that enters the classification tank 13 returns to the recovery tank 2b through the return channel 2f. Of course, the concrete slurry that returns to the recovery tank 2b is then sent again to the distribution header 12 of the sand separation section 2c through the recovery / sand separation channel 2d by the operation of the pump 2e, as described above. By adopting a configuration in which a portion of the concrete slurry is circulated between the recovery tank 2b and the sand separation section 2c, the flow in the recovery / sand separation channel 2d can be stabilized sufficiently from the start to the end of the residual concrete processing, thereby preventing clogging of the recovery / sand separation channel 2d. Furthermore, the return channel 2f is provided with an electrically controlled on / off valve 18, and by appropriately opening and closing the on / off valve 18, the amount of concrete slurry returned to the recovery tank 2b can be arbitrarily adjusted.

[0022] [3-5. Sand Separation and Input Channels] The aforementioned sand separation and input channel 2g connects the sand separation section 2c and the input section 1. As shown in Figure 3, one end is connected to the distribution header 12 and the other end is connected to the hopper 5 of the input section 1. As shown in the enlarged view of Figure 3, a rectangular overflow chamber 19 is formed inside the distribution header 12, and the sand separation and input channel 2g is connected to this overflow chamber 19. Therefore, when the concrete slurry is sent from the recovery tank 2b to the distribution header 12, the liquid surface of the concrete slurry flows into the overflow chamber 19, and it is supplied to the hopper 5 of the input section 1 through the sand separation and input channel 2g.

[0023] [4.Solid-liquid separation section] The solid-liquid separation unit 4, which is a slurry processing device, separates the solid material from the treated water by allowing the cement-containing solid material to settle from the concrete slurry after the aggregate separation unit 2 has separated the gravel G and sand S.

[0024] The solid-liquid separation unit 4 of this embodiment is generally composed of a treatment tank 3 in which concrete slurry is slowly flowed to allow solid matter to settle, and a removal device 20 for removing the solid matter that has settled in the treatment tank 3 to the outside, as shown in Figures 5 to 10-2.

[0025] [4-1. Treatment Tank] The treatment tank 3 is made almost entirely of metal (steel) and consists of a long, narrow rectangular bottom section 3a, side plates 3b, 3b erected perpendicularly to both long sides of the bottom section 3a, a rear side plate 3c erected perpendicularly to one short side of the bottom section 3a, an inclined surface plate 3e that extends from the other short side of the bottom section 3a at an upward slope of approximately 30 degrees and has a discharge port 3d at approximately its upper end, and side wall plates 3f, 3f that surround both sides of the inclined surface plate 3e. Furthermore, above the treatment tank 3, a top plate 3h is provided, supported by multiple support columns 3g at the same height as the upper edge level of the inclined surface plate 3e.

[0026] A partition plate 3i is provided upright on the bottom surface 3a of the treatment tank 3, running parallel to the side plates 3b, 3b from approximately the center of the rear plate 3c, and this partition plate 3i divides the inside of the treatment tank 3 into a first area 3j and a second area 3k. At the end of the partition plate 3i opposite the rear plate 3c, a gap is provided between it and the inclined surface plate 3e, as shown in Figure 5, and this gap serves as a water passage 3m, connecting the first area 3j and the second area 3k.

[0027] At the rear plate 3c side (opposite the water passage 3m; hereinafter referred to as the "starting end side") of the first area 3j of the treatment tank 3, the end of the classification / solid-liquid separation channel 16, which is connected to the overflow trough 15 of the sand separation section 2c, is open. As a result, the concrete slurry, after the gravel G and sand S have been separated in the aggregate separation section 2, flows through the classification / solid-liquid separation channel 16 to the starting end side of the first area 3j.

[0028] Furthermore, as shown in the plan view of Figure 1, a car wash 21 is installed alongside the first area 3j of the treatment tank 3, and the height of the side plates 3b, 3b of the treatment tank 3 is set lower than the discharge level of the mixer truck M's chute C, so that the residual water used to clean the inside of the mixing drum D in the car wash 21 can be discharged into the first area 3j. Note that the partition plate 3i of the treatment tank 3 is formed to be sufficiently higher than the side plates 3b, 3b, so even if the residual water from the mixing drum D is forcefully discharged into the first area 3j, there is no risk of it splashing into the second area 3k.

[0029] On the other hand, at the rear side plate 3c side of the side plate 3b of the second area 3k (opposite the water passage section 3m; hereinafter referred to as the "terminal side"), a drainage gate 3n is provided, for example, by stacking multiple horizontal pipes vertically to allow treated water to be slowly discharged through the small gaps between each pipe. Therefore, the concrete slurry that flows into the starting end of the first area 3j flows along the partition plate 3i towards the water passage section 3m, as indicated by the arrow in the plan view of Figure 5, enters the second area 3k from the water passage section 3m, changes direction of flow, and is discharged to the outside through the drainage gate 3n provided at the end of the second area 3k. By making the concrete slurry make a U-turn from the first area 3j at the water passage section 3m and flow towards the end of the second area 3k in this way, the time that the concrete slurry remains in the treatment tank 3 can be extended, allowing more solid matter in the concrete slurry to settle during that time.

[0030] As shown in the plan view of Figure 1, a sedimentation tank 23 is provided next to the treated water tank 3, and the sedimentation tank 23 and the drain gate 3n of the treated water tank 3 are connected by a trough-shaped treatment / sedimentation channel 24. Therefore, the treated water discharged from the drain gate 3n flows into the sedimentation tank 23 through the treatment / sedimentation channel 24, where further fine solid matter settles, separating the sediment from the treated water.

[0031] The sedimentation tank 23 is provided with a concave sump 23b at the corner of the bottom 23a, and a sedimentation tank pump 23c is installed in the sump 23b. As shown in the flow diagram in Figure 11, the sedimentation tank pump 23c is connected to the input unit 1 and the car wash area 21 by a treated water distribution channel 23d. The treated water, drawn up from the bottom 23a side of the sedimentation tank 23 by the sedimentation tank pump 23c, is used for adjusting the moisture content of the concrete slurry at the input unit 1 and for cleaning the mixing drum D at the car wash area 21. Furthermore, by intentionally drawing up treated water from the sump 23b at the bottom 23a of the sedimentation tank 23 using the sedimentation tank pump 23c, the sediment is also drawn up. However, by reintroducing this sediment into the treated water tank 3 via the input unit 1 or the mixing drum D of the mixer truck M, as in the embodiment, the sediment is ultimately mixed with other solids in the treated water tank 3 and treated. This reduces the cost of separately treating the sediment that accumulates in the sedimentation tank 23.

[0032] [4-2. Extraction device] The removal device 20 of this embodiment is used to scoop up solid matter that has settled and accumulated on the bottom surface 3a of the treatment tank 3 and discharge it to the outside. It is generally composed of a rake unit 25 for scooping up solid matter and a drive unit 26 for driving the rake unit 25.

[0033] [4-2-1. Drive Unit] As shown in Figures 5 to 10-2, the drive unit 26 consists of an endless conveyor chain 26a and a drive mechanism 26b that drives the conveyor chain 26a.

[0034] [4-2-1a. Conveyor chain] The conveyor chains 26a are of the same standard and come in sets of two, with one set each installed in the first area 3j and the second area 3k of the treated water tank 3, for a total of four chains. The conveyor chain 26a is a so-called roller chain, consisting of a large number of links 26c linked together in an endless manner with rollers 26d in between, and specific links 26c having airfoil-shaped attachments 26e are incorporated at regular intervals.

[0035] As shown in Figures 5 and 6, each conveyor chain 26a is wrapped around a sprocket 26f rotatably supported near the upper end of the side wall plate 3f of the inclined panel 3e, a guide rail 26g provided on the upper surface of the top plate 3h above the treatment tank 3, a guide wheel 26h rotatably supported at the rear side plate 3c end of the side plates 3b, 3b of the treatment tank 3, and an arc-shaped tension rail 26i provided at the boundary between the bottom surface 3a of the treatment tank 3 and the inclined panel 3e. This allows for endless circulation of a scraping path along the bottom surface 3a of the treatment tank 3 and the inclined panel 3e, and a return path from approximately the upper end of the inclined panel 3e, passing over the top plate 3h above the treatment tank 3 and returning to the bottom surface 3a.

[0036] [4-2-1b. Drive Mechanism] The drive mechanism 26b consists of a rotating shaft 26j integrated with the sprocket 26f, a motor 26k for rotating the rotating shaft 26j, and a chain 26m for transmitting the rotation of the motor 26k to the rotating shaft 26j. The motor 26k is mounted on a mounting base 26n provided on the upper part of the side wall plate 3f of the inclined face plate 3e. As described above, two conveyor chains 26a of the same specifications are provided in both the first area 3j and the second area 3k of the treated water tank 3. By driving the motor 26k of the drive mechanism 26b, all conveyor chains 26a slowly circulate at the same speed along the respective scooping and return paths of the first area 3j and the second area 3k.

[0037] [4-2-2. Rake Unit] As shown in the perspective view of Figure 9 and the exploded perspective view of Figure 10-1, the rake unit 25 consists of a plate-shaped rake 25a that rubs against the bottom surface 3a and the inclined surface plate 3e of the treatment water tank 3 to scrape up solid matter, a pair of clamp plates 25f and 25r that sandwich and fix the rake 25a from the front and back, and bolts 25b and nuts 25c that tighten the clamp plates 25f and 25r together in a direction that crushes the rake 25a.

[0038] [4-2-2a. Rake] The rake 25a is made of wear-resistant rubber and is a horizontally oriented rectangular flat plate with its longer side having a length approximately equal to the width of the first area 3j and the second area 3k of the treatment water tank 3. The rake 25a has multiple vertically elongated through holes 25d arranged in a horizontal row (for example, three), through which the bolts 25b pass, and the vertical position relative to the clamp plates 25f and 25r can be adjusted within the range of the vertical length of the through holes 25d. Note that the rake 25a can also be made of metal.

[0039] [4-2-2b. Clamp Plate] The clamp plates 25f and 25r are horizontally oriented rectangular metal plates that have approximately the same width as the rake 25a and are slightly shorter in height than the rake 25a. A clamp plate 25r that supports the rear side of the rake 25a in the direction of travel has a mounting plate 25e that extends almost horizontally from its upper edge, and the attachments 26e of the conveyor chain 26a are screwed to both ends of the mounting plate 25e, and in this way the rake unit 25 is attached to the two conveyor chains 26a, 26a at a predetermined interval.

[0040] On the other hand, the clamp plate 25f that supports the front side of the rake 25a is provided with a convex grip portion 25i that compresses the rake 25a on the surface that contacts the rake 25a, as shown in Figures 10-1 and 10-2. The grip portion 25i is provided with numerous elongated ribs 25j having a predetermined length (for example, 0.2 to 0.3 times the length of the shorter side of the rake 25a) and a predetermined projection height (for example, 0.1 to 0.2 times the thickness of the rake 25a). Specifically, as shown in Figures 10-2(a) and (b), the ribs 25j are provided projecting at inclinations of θ° and -θ° on the intersection of a diagonal grid 25z, which is composed of a virtual parallel diagonal line 25x inclined at θ° (approximately 45° in the embodiment) with respect to the horizontal lower edge of the clamp plate 25f, and a virtual parallel diagonal line 25y inclined at -θ° (approximately -45° in the embodiment). The arrangement pattern of the ribs 25j is arbitrary, but for example, as shown in Figures 10-1 and 10-2(a), the inclination of the vertical columns can be unified in one direction, and the inclination of the adjacent vertical columns can be unified in the opposite direction, or as shown in Figure 10-2(b), the ribs 25j can be placed at the four corners of the cells of the diagonal grid 25z so as to be rotationally symmetrical four times with respect to the center of the cell.

[0041] [4-2-2c. Bolts and Nuts] The bolt 25b and nut 25c used to fasten the clamp plates 25f and 25r are configured such that, in the tightened state shown in Figure 7, the tip of the bolt 25b is submerged in the female screw hole 25g of the nut 25c and does not protrude to the outside. As a result, solid matter (mainly cement) in the concrete slurry does not adhere to or solidify around the male thread 25h of the bolt 25b, making it easy to tighten and loosen the bolt 25b when replacing or adjusting the rake 25a. Furthermore, the nut 25c is welded to the clamp plate 25r, preventing concrete slurry from entering the female screw hole 25g from the joint.

[0042] [4-3. Solid-Liquid Separation Treatment] Next, we will explain the solid-liquid separation process performed by the solid-liquid separation unit 4 (slurry processing device). As described above, the end of the classification / solid-liquid separation channel 16, which is connected to the overflow trough 15 of the sand separation section 2c, is open at the starting end of the first area 3j of the treatment tank 3. Therefore, the concrete slurry, after the gravel G and sand S have been separated in the aggregate separation section 2, flows into the starting end of this channel. Then, the concrete slurry that enters the first zone 3j flows along the partition plate 3i towards the water passage section 3m, as shown by the arrow in Figure 5, enters the second zone 3k from the water passage section 3m, flows through the second zone 3k in the opposite direction to the first zone 3j, reaches the drain gate 3n at the end, and is discharged from the drain gate 3n into the treatment / sedimentation channel 24. By causing the concrete slurry to make a U-turn at the 3m water passage and flow through the first zone 3j and the second zone 3k, the residence time of the concrete slurry in the treatment tank 3 is increased. Consequently, more solid matter in the concrete slurry settles.

[0043] Then, by causing the conveyor chain 26a to rotate at a low speed using the drive mechanism 26b, the rake 25a slowly moves along the raking path, collecting the solid material X accumulated on the bottom surface 3a as shown in Figure 7, and further raking the solid material X up above the liquid surface along the inclined surface plate 3e. By moving the rake 25a slowly in this manner, it is possible to suppress the solid matter X that has settled once from rising again. At the same time, much of the water that is scooped up above the liquid surface along with the solid matter X flows down the inclined face plate 3e and returns to the treatment water tank 3, resulting in better drainage. As a result, the solid matter X with a low water content is discharged from the outlet 3d to the recovered solid matter solidification plant 27.

[0044] Furthermore, the solid material X discharged to the solidification plant 27 hardens into a solid mass due to the hydration reaction of the cement it contains, and can therefore be disposed of as stable waste. In addition, this resulting solid mass of stable waste can be effectively utilized as roadbed material by crushing it to a certain size using a crusher (not shown).

[0045] Incidentally, when the rake 25a of the solid-liquid separation section 4 moves along the scraping path, it receives a tensile force in the direction of being pulled out from the clamp plates 25f and 25r due to the frictional resistance between its lower edge and the accumulated solid material and the resistance that pushes the solid material, and is released from this tensile force when moving along the return path. Therefore, the rake 25a, while sandwiched between the clamp plates 25f and 25r, is subjected to repeated stress over a long period of time, being strongly pulled in the raking path and released in the return path. However, although the rake 25a is a flat plate of uniform thickness, multiple through holes 25d for passing bolts 25b are provided in a horizontal row, so the cross-sectional area of ​​the part that crosses these through holes 25d is smaller than the cross-sectional area of ​​other parts. Therefore, it is more strongly affected by the stress caused by the repeated tension and release described above compared to other parts, making it more likely that cracks will form in that part or that it will eventually break.

[0046] In contrast, the rake 25a of the embodiment is securely locked by the compression of the rib 25j of the grip portion 25i provided on the clamp plate 25f, so that the stress caused by the repeated tensioning and releasing described above is less likely to be transmitted to the area where the through hole 25d is provided. Therefore, the risk of the rake 25a breaking is reduced. The rib 25j of the grip portion 25i may be parallel to the lower edge of the clamp plate 25f, but as in this embodiment, by inclining it in a predetermined pattern with inclinations of θ°=45° and -θ°=-45° relative to the horizontal lower edge of the clamp plate 25f, the tensile force acting on the rake 25a is distributed in the direction along the rib 25j and in the direction perpendicular thereto, thereby further reducing the risk of breakage of the rubber rake 25a.

[0047] In this embodiment, the rake 25a of the solid-liquid separation unit 4 is mounted in a prone position, as shown in Figure 7, with its front surface having an inclination angle α of approximately 3° to 10° relative to the direction of travel, with respect to a perpendicular line that intersects the bottom surface 3a of the treatment tank 3. This suppresses the noise emitted from the rake 25a due to friction with the bottom surface 3a of the treatment tank 3. However, by tilting the rake 25a in a prone position, solid matter X can easily get trapped under the rake 25a as it moves along the bottom surface 3a of the treatment tank 3, potentially increasing frictional resistance. Therefore, there is a concern that the stress acting on the rake 25a may increase. However, this concern can be eliminated by providing a grip portion 25i on the clamp plate 25f, as in this embodiment. Therefore, the present invention maximizes the benefits obtained by providing the inclination angle α by applying the rake 25a to the solid-liquid separation unit 4, which is mounted in a prone position with respect to the direction of travel, having an inclination angle α of approximately 3° to 10° with respect to a perpendicular line that intersects perpendicularly with the bottom surface 3a of the treatment water tank 3.

[0048] [5. Disposal of leftover concrete] The residual concrete processing device of this embodiment has the above configuration, and the residual concrete processing using this residual concrete processing device will be described below. First, the mixer truck M loaded with leftover concrete is parked in the parking space in front of the leftover concrete storage tank 1a of the input section 1. After all the leftover concrete in the mixing drum D is discharged into the leftover concrete storage tank 1a, the mixer truck M is moved to the car wash area 21 next to the treated water tank 3. Meanwhile, the remaining concrete discharged into the remaining concrete storage tank 1a is immediately scooped up with a power shovel or the like and transferred to the hopper 5 side of the quantitative supply device 1b.

[0049] Next, water is added to the remaining concrete in the hopper 5, and it is mixed with the screw 6 to adjust it into a highly fluid concrete slurry, which is then transferred towards the gravel separation section 2a of the aggregate separation section 2. The water added to the remaining concrete in the hopper 5 is selected from the treated water accumulated in the sedimentation tank 23, the concrete slurry distributed from the distribution header 12, and an external water source (not shown), either individually or in appropriate combinations depending on the situation. For example, at the start of processing, if there is treated water accumulated in the sedimentation tank 23, it is used preferentially. As the processing progresses and the concrete slurry enters the distribution header 12, the concrete slurry from the distribution header 12 is used preferentially. By doing so, water can be saved by reducing the supply from an external water source, and the increase in concrete slurry and thus the processing volume caused by adding external water can also be suppressed.

[0050] Next, the concrete slurry, transported to the end of the quantitative supply device 1b by the drive of the screw 6, falls onto the sieve 8 of the gravel separation section 2a, where it is sieved into gravel G of a predetermined particle size or larger and concrete slurry mixed with sand. The gravel remaining on the sieve 8 is sent laterally by vibration and transported via the belt conveyor 9 to the recovered gravel storage area 10. The gravel G accumulated in the recovered gravel storage area 10 is then recovered by a power shovel or the like and reused as a resource.

[0051] Meanwhile, the sand-mixed concrete slurry that passes through the sieve 8 in the gravel separation section 2a temporarily accumulates in the recovery tank 2b below, from where it is sucked up by the pump 2e at the bottom 2h and sent through the recovery / sand separation channel 2d to the distribution header 12 of the sand separation section 2c. Then, most of the concrete slurry that enters the distribution header 12 flows down into the classification tank 13 below, but a portion near the liquid surface (for example, about 30% of the concrete slurry that enters the distribution header 12) flows into the overflow chamber 19 within the distribution header 12, and is supplied to the input section 1, specifically the hopper 5 of the input section 1, through the sand separation and input channel 2g, to be used to prepare the remaining concrete into a highly fluid concrete slurry.

[0052] Furthermore, a portion of the concrete slurry that flows from the distribution header 12 to the classification tank 13 (for example, about 60% of the concrete slurry entering the distribution header 12) returns to the recovery tank 2b through the return channel 2f from the lowest point of the bottom 11. The concrete slurry that returns to the recovery tank 2b mixes with the concrete slurry that has fallen from the sieve 8 of the gravel separation section 2a and is sent back to the sand separation section 2c. By forcibly circulating a portion of the concrete slurry between the recovery tank 2b, the recovery / sand separation channel 2d, the sand separation section 2c, and the return channel 2f in this way, the amount of concrete slurry flowing through the recovery / sand separation channel 2d can be stabilized to a sufficient degree, thereby preventing clogging of the recovery / sand separation channel 2d by the concrete slurry. The amount of concrete slurry to be forcibly circulated can be arbitrarily adjusted by appropriately controlling the opening and closing time of the on-off valve 18 provided in the return channel 2f.

[0053] Meanwhile, the sand contained in the concrete slurry that enters the classification tank 13 settles at the bottom 11 and is transported diagonally upward by the screw conveyor 14. As it passes through the liquid surface and rises further, it is dewatered and finally falls into the recovered sand storage area 17 where it accumulates. The sand S accumulated in the recovered sand storage area 17 is then recovered by a power shovel or the like and reused as a resource.

[0054] Furthermore, any concrete slurry other than those mentioned above that enters the classification tank 13 flows out into the overflow gutters 15 provided on both sides of the upper outer surface of the classification tank 13, and is sent through the classification / solid-liquid separation channel 16 to the starting end of the first area 3j of the solid-liquid separation section 4, specifically the treated water tank 3.

[0055] Next, the solid-liquid separation unit 4, which receives the concrete slurry from the sand separation unit 2c, separates the concrete slurry into solid matter and treated water by the settling of solid matter and the scraping up of solid matter X by the removal device 20, as detailed in section [4-3. Solid-liquid separation treatment]. In other words, the solid-liquid separation unit 4 slowly flows the concrete slurry that has entered the starting end of the first zone 3j of the treatment tank 3 through the water passage section 3m toward the terminal end of the second zone 3k, allowing solid materials such as cement to settle on the bottom surface 3a of the treatment tank 3. The solid materials accumulated in the first zone 3j and the second zone 3k are then collected by a rake 25a and discharged to the solid material solidification area 27 from the discharge port 3d at the top of the inclined face plate 3e, while the treated water is discharged from the drainage gate 3n of the second zone 3k and stored in the sedimentation tank 23.

[0056] The solid material obtained from the concrete slurry hardens into a hard mass due to the hydration reaction of cement, and can be effectively used as roadbed material by crushing it into a certain size, for example, with a crusher (not shown). Meanwhile, the treated water obtained from the concrete slurry is stored in the sedimentation tank 23 and sent from there to the input unit 1 and / or car wash 21 via the treated water distribution channel 23d, where it is used to add water to the remaining concrete in the input unit 1 and to clean the mixing drum D in the car wash 21. Furthermore, the treated water accumulated in the sedimentation tank 23 still contains fine solid matter, which settles and accumulates at the bottom 23a of the sedimentation tank 23. This sediment is then sucked up together with the treated water by the sedimentation tank pump 23c and introduced into one of the locations between the input section 1 and the treated water tank 3, such as via the input section 1 or the mixing drum D, and is finally mixed with the solid matter in the solid-liquid separation section 4 for treatment. Therefore, the effort required to separately treat the sediment in the sedimentation tank 23 is significantly reduced.

[0057] Meanwhile, after the mixer truck M discharges the remaining concrete into the input section 1 and moves to the car wash area 21, it immediately cleans the inside of the mixing drum D using the treated water from the sedimentation tank 23 at the car wash area 21. Then, the residual water generated by the washing process is directly discharged into the first area 3j of the treatment tank 3 of the solid-liquid separation unit 4, and the solid-liquid separation process by the solid-liquid separation unit 4 is immediately started. therefore, (i) A series of residual concrete processing steps performed by feeding the residual concrete into the input section 1, (ii) A solid-liquid separation treatment is performed by introducing the residual water generated from cleaning the mixing drum D into the treatment tank 3 of the solid-liquid separation unit 4, in a manner that skips the aggregate separation unit 2 process, Because these processes are carried out simultaneously, the burden on the aggregate separation unit 2 is reduced, and the overall processing time can be shortened. The solid-liquid separation unit 4 of this embodiment is designed to solidify the solid material X into a hard mass through the hydration reaction of cement, and therefore, the series of residual concrete treatments must be completed within approximately 13 hours, which is the time it takes for the cement to mix with water and begin to harden through the hydration reaction. Thus, the effect obtained by shortening the processing time is significant.

[0058] Although embodiments of the present invention have been described above, the present invention is of course not limited to the above embodiments. For example, in the embodiments, the grip portion 25i was formed with a rib 25j of a predetermined length, but it may also be a continuous rib extending from left to right across the clamp plate 25f. Furthermore, in this embodiment, the grip portion 25i is provided on the clamp plate 25f, but it may also be provided on the clamp plate 25r on the opposite side. However, since the clamp plate 25f can be easily replaced by attaching and detaching the bolt 25b, providing the grip portion 25i on the clamp plate 25f is advantageous in that it makes it easier to modify the existing rake unit 25 to include the grip portion 25i. Furthermore, in this embodiment, θ° was set to approximately 45°, but it may also be set to, for example, approximately 30°. In this embodiment, the ribs 25j of the grip portion 25i are provided protruding from the intersections of the oblique grid 25z formed by virtual parallel diagonal lines 25x and 25y, but they may be distributed randomly. [Explanation of Symbols]

[0059] 3. Treatment tank 3a...Bottom part 4. Solid-liquid separation unit (slurry processing device) 25 ... Rake Unit 25a ... Rake 25b ... Bolt 25c ... nut 25f, 25r ... Clamp plate 25i ... Grip section 25j... Rib 25x, 25y ... virtual parallel diagonal lines 25z ... diagonal grid X…Solid matter

Claims

1. A treatment tank for settling solid matter contained in the slurry, A slurry processing apparatus having a rake unit that moves along the bottom surface of the processing tank, scrapes the settled solid material with a plate-shaped rubber rake, and discharges it to the outside, The aforementioned rake unit is, A pair of clamping plates that sandwich the rake from the front and back, The clamp plates are fastened together with bolts and nuts in a direction that sandwiches the rake, A slurry processing apparatus characterized in that at least one of the clamp plates has a convex grip portion on the surface in contact with the rake that compresses the rake.

2. The slurry processing apparatus according to claim 1, characterized in that the grip portion is provided with a number of elongated ribs of a predetermined length that are inclined at an angle of θ° with respect to the lower edge of the clamp plate, and elongated ribs of a predetermined length that are also inclined at an angle of -θ°.

3. The slurry processing apparatus according to claim 2, characterized in that the ribs of the grip portion are provided protruding from the intersection of a diagonal grid formed by a virtual parallel diagonal line inclined at θ° with respect to the lower edge of the clamp plate and a virtual parallel diagonal line inclined at -θ°.

4. The slurry processing apparatus according to claim 2 or 3, characterized in that the θ° is approximately 45°.

Images