JP5416557B2 - Scum collection device - Google Patents

Description

The present invention comprises a scum discharge rod for discharging scum floating near the surface of a sedimentation tank (sedimentation basin) used in a sludge treatment facility, a sewage treatment facility, and the like, a scum scraping plate for scraping the scum, etc. The present invention relates to a scum recovery device.

  In the settling tank, sludge and scum are removed from the contaminated water as follows. When polluted water flows into the settling tank, the sludge sinks to the bottom and the scum rises. Sludge is scraped and collected by a sludge scraping plate that rotates at the bottom of the sedimentation tank body, and scum is scraped by a scum scraping board that rotates on the water surface of the sedimentation tank body and guided onto the guide plate. After that, it falls to the scum discharge rod adjacent to the back side and is collected. On the other hand, the sewage (supernatant water) from which sludge and scum have been removed passes over the overflow weir and is discharged to another tank.

  The following is known as a scum recovery device that recovers scum in the manner described above (Patent Document 1). This is because a rotating shaft is installed at the center of the sedimentation tank body, a scum scraping plate for scraping the scum is installed near the water surface of the sedimentation tank body, and the scum scraping plate is rotated by the rotating shaft. Further, a scum discharge rod having a U-shaped cross section is installed in the vicinity of the water surface of the settling tank body, and a guide plate is provided on the discharge rod near the scum scraping plate. The guide plate is inclined so as to become lower in the direction in which the scum approaches. When the rotating shaft is rotated, the scum is scraped by the scum scraping plate, moves along the guide plate from the water surface, is guided slightly above the water surface, and then falls to the scum discharge rod, and the precipitation tank body Is collected outside.

JP 2001-269663 A

  However, the present inventor has noticed that the scum adheres to the scum scraping plate that has passed through the scum discharge rod even though the scum is dropped by the scum discharge rod. Then, the cause of scum adhesion was considered.

  When the scum scraping plate scrapes the scum and pushes it along the guide plate, the scum is pushed up above the top of the guide plate (the top of the scum discharge rod) and then falls to the scum discharge rod. However, not all of the scum pushed up above the top of the guide plate falls, but some of it adheres to the scum scraping plate and passes through the scum discharge rod as it is.

  Therefore, the present inventor thought that this problem could be solved by devising the scum discharge rod. As shown in FIG. 7 (a), the scum discharge rod 91 has a U-shaped cross section. More specifically, the front piece 91a toward which the scum scratching plate 92 approaches (the one where the guide plate 93 continues), the back piece 91b from which the scum scratching plate 92 moves away, and these pieces It is a shape comprised from the bottom piece 91c which connects. The point to be noted is that the front piece 91a and the back piece 91b have the same height.

  In such a shape, the scum S at a position above the top of the scum discharge rod 91 until the scum scraping plate 92 rotates and passes over the scum discharge rod 91 is Since the front piece 91a and the back piece 91b are not rubbed, they remain attached to the scum scraping plate 92 as they are. That is, until the scum scratching plate 92 rotates and passes over the scum discharge rod 91, the scum scratching plate 92 rubs on the guide plate 93 as shown in FIG. It moves into the scum discharge rod 91 as shown in FIG. 7 (b), is rubbed against the back piece 91b as shown in FIG. 7 (c), and the top of the scum discharge rod 91 as shown in FIG. 7 (d). Until it passes.

  The present invention was created in view of the above circumstances, and the problem to be solved is to collect as much scum as possible when passing through the scum discharge rod, and to prevent scum from adhering to the scum scraping plate as much as possible. It is to be.

In the present invention , after the scum scraping plate rotates around the rotation shaft provided at the center of the precipitation tank body, and passes through the guide plate with a gradient disposed near the water surface while rubbing. A scum recovery device that recovers falling scum to a scum discharge rod located on the back side of the guide plate is assumed.

In the invention of claim 1, the scum discharge rod connects the front piece toward which the scum scraping plate approaches, the back piece from which the scum scratching plate separates, and the front piece and the back piece. by a bottom piece is formed to have a U-shaped cross section, e Bei member and scum scraping position higher than the front piece even far side from the front piece, on each upper part of the front piece and Okuhen position higher than the water surface It is arranged .

  It does not matter whether the scum scraping member is a part of the back piece. For example, a roller-like or strip-like scum scraping member is supported at a position intermediate between the rear piece and the front piece and higher than the front piece, and the scum scraping member is placed on the scum scraping member. It may be one that passes while rubbing the rubbing member. However, considering the simplicity of the structure, it is desirable to do the following. That is, as in the invention of claim 2, the scum scraping member is the upper end portion of the back piece.

According to the first aspect of the present invention, since the scum scraping member is provided at a position deeper than the front piece and higher than the front piece, the rotating scum scraping plate moves while rubbing on the scum scraping member. By doing so, the scum adhering to the scum scraping plate that is above the front piece can be scraped off. Moreover, since each upper part of a back piece and a front piece is arrange | positioned in the position higher than a water surface, the quantity of the sewage collect | recovered with a scum is small.

  In the invention of claim 2, since the upper part of the back piece is used as a scum scraping member, the structure has a simple and excellent effect of scraping off the scum.

(A)-(E) are sectional views showing the relationship between the scum discharge rod and the scum scraping plate. It is a perspective view which shows the shape of a guide plate in relation to a rotating shaft etc. (A) and (B) are sectional views showing the relationship between the scum discharge rod and the scum scraping plate on the outer peripheral side and the inner peripheral side. It is sectional drawing which shows the outline | summary of a sedimentation tank. It is the sectional view on the AA line of FIG. It is an expanded sectional view which shows the relationship between the overflow basin, the surrounding wall of a sedimentation tank main body, and a scum discharge basin. It is sectional drawing which shows the relationship between the conventional scum discharge gutter and a scum scraping board.

  As shown in FIG. 4 or FIG. 5, the sedimentation tank is a sedimentation tank main body 1, a polluted water inflow device 2 that allows the polluted water to flow into the sedimentation tank main body 1, and sludge that collects sludge collected at the bottom of the sedimentation tank main body 1. A recovery device 3, a scum recovery device 4 that recovers the scum S that floats on the water surface of the settling tank body 1, and a sewage discharge device 5 that discharges sewage (supernatant water) from which scum S and sludge have been removed from the contaminated water It is to be prepared. Hereinafter, these configurations will be described in detail.

  The sedimentation tank main body 1 is made of concrete, for example, and when viewed in plan, the inner peripheral surface of the peripheral wall 11 is circular. And the lower end part of the surrounding wall 11 which made the internal peripheral surface cylindrical is obstruct | occluded with the floor wall 12. FIG. The upper surface of the floor wall 12 is formed into a tapered surface whose center is deeper than the surroundings. A ceiling 13 is provided at the upper end of the peripheral wall 11, and a motor 14 (deceleration motor) and a bearing 15 are placed on the ceiling 13. A rotating shaft 16 that is rotated by the motor 14 is suspended by a bearing 15 at the center position of the settling tank body 1.

  The polluted water inflow device 2 guides the inflow pipe 21 from the outer side to the inner side of the peripheral wall 11. The inflow pipe 21 extends sideways up to the vicinity of the center portion of the settling tank main body 1, and its tip portion is directed upward. A cylindrical baffle plate 22 is provided concentrically around the rotating shaft 16. The baffle plate 22 is disposed below the surface of the water and is fixed by support arms 23 that extend radially with respect to the rotating shaft 16. The tip of the inflow pipe 21 is inserted into the inside of the baffle plate 22 from the lower side near the center.

  The polluted water discharged into the baffle plate 22 from the inflow pipe 21 loses momentum in the baffle plate 22, and the scum S contained in the polluted water rises, and the sludge contained in the polluted water sinks. Further, since the tip portion of the inflow pipe 21 faces upward, the scum S easily floats, and the scum S tends to concentrate on the upper side of the baffle plate 22, that is, on the center side of the sedimentation tank body 1.

  As shown in FIGS. 4 to 6, the sewage discharge device 5 is provided with an overflow basin 51 on the inner peripheral side at the upper part of the peripheral wall 11 of the sedimentation tank body 1, 52 is connected to guide the sewage discharge pipe 52 to the outside of the settling tank body 1. The overflow basin 51 is made of metal, for example, and is provided in a donut shape over the entire inner circumference side of the peripheral wall 11. In addition, the overflow basin 51 is attached to the peripheral wall 11 at a plurality of locations on the entire periphery thereof via the bracket 53 so as to be separated from the inside. Therefore, the area where the peripheral wall 11 of the settling tank main body 1 and the overflow basin 51 are separated has a donut shape in plan view, and becomes a supernatant water recovery area (sewage recovery area). Moreover, the area | region enclosed inside the overflow basin 51 becomes circular shape in planar view, and becomes a scum collection | recovery area | region.

  As shown in FIG. 6, the cross-sectional shape of the overflow basin 51 is a groove shape that opens upward, and an outer peripheral piece 54 and an inner peripheral piece 55 that are arranged inside and outside concentrically with respect to the center of the settling tank body 1. In addition, the bottom 56 of the outer peripheral piece 54 and the inner peripheral piece 55 is connected to the bottom piece 56 to connect and close.

  The outer peripheral piece 54 is an overflow weir, and this determines the height of the water surface. The outer peripheral piece 54 is formed lower than the inner peripheral piece 55. The sewage in the supernatant collection area located outside the outer peripheral piece 54 passes over the outer peripheral piece 54 and flows into the overflow basin 51.

  Further, a sewage discharge pipe 52 is connected to the outer peripheral piece 54, and the sewage discharge pipe 52 is led to another tank installed outside the precipitation tank body 1.

  The inner peripheral piece 55 acts like a levee so that the scum S accumulated in the scum collection area does not get over.

  The bottom of the heel bottom 56 has a triangular shape. Further, the bottom surface of the bottom 56 is formed in a tapered surface whose outer peripheral portion is lower than the inner peripheral portion. Therefore, the scum S that has floated directly below the bottom surface of the bottom 56 is guided to the scum recovery area located inside the inner peripheral piece 55 along the tapered surface.

  As shown in FIG. 4 or 5, the scum recovery device 4 includes the motor 14, the bearing 15, the rotating shaft 16, the scum scraping plate 41 that rotates near the water surface around the rotating shaft 16, and the water surface. A guide plate 42 with a gradient disposed near the scum scraping plate 41 while being rubbed (rubbed); a scum discharge rod 43 disposed on the back side in the circumferential direction of the guide plate 42; A scum discharge pipe 44 connected to the scum discharge rod 43 is provided.

  As shown in FIG. 1 or FIG. 2, the scum scraping plate 41 is a scum arm 41a fixed in a state of extending radially with respect to the rotary shaft 16, and a flexible rubber fixed along the scum arm 41a. It is comprised from the scraping board main body 41b for a scum. The scum scraping plate main body 41b is in a state of hanging down from above the water surface until reaching the water. When the scum scraping plate 41 is rotated by the rotation of the rotating shaft 16, the scum S floating on the water surface is scraped by the deforming scum scraping plate main body 41b and moved onto the guide plate 42, and the scum It falls into the discharge tank 43, passes through the scum discharge pipe 44, and is collected in another tank installed outside the precipitation tank body 1.

  As shown in FIGS. 1 and 3 to 5, the scum discharge rod 43 has a front piece 43 a disposed on the front side in the rotational direction of the scum scraping plate 41 and a rear side in the rotational direction of the scum scraping plate 41. It is formed by opening upward in a U-shaped cross section from the rear piece 43b to be arranged and the bottom piece 43c connecting the lower end portions of the front piece 43a and the rear piece 43b, and the inner peripheral side and the outer peripheral side of the U-shaped cross section are closed. Has been. The lower portion of the scum discharge rod 43 is submerged and the upper portion thereof is formed higher than the water surface so that the scum S does not naturally enter. The back piece 43b is formed higher than the front piece 43a. The height difference d between the back piece 43b and the front piece 43a is specifically 10 cm or more. This high portion, that is, the upper end portion of the back piece 43b becomes the scum scraping member 43d.

  Further, when viewed in plan, the front piece 43 a and the back piece 43 b extend radially from the vicinity of the outer periphery to the overflow basin 51 around the rotation shaft 16. In addition, the distance between the front piece 43a and the back piece 43b becomes narrower as the rotary shaft 16 is approached.

  Furthermore, the outer periphery of the scum discharge rod 43 is fixed to the inner peripheral piece 55 of the overflow rod 51 by welding or the like. That is, the scum discharge rod 43 is cantilevered stably by the overflow rod 51. Further, the bottom of the scum discharge rod 43 is inclined so as to gradually become lower toward the outer peripheral portion, and the scum discharge pipe 44 is connected to the bottom of the outer peripheral portion. The scum discharge pipe 44 is guided to the outside of the settling tank body 1 in a state where it hangs obliquely.

  As shown in FIGS. 2 to 5, the guide plate 42 has a fan shape (fan shape) in plan view extending radially from the vicinity of the outer periphery around the rotation shaft 16, and includes a spiral guide plate main body 42a. The guide plate main body 42a is provided with a horizontal belt-like hem plate 42b that is continuous with one of the two sides along the radial direction of the guide plate main body 42a that the scum scraping plate 41 approaches (front side).

  The guide plate main body 42a holds one side (the back side) fixed to the scum discharge rod 43 among two sides along the radial direction of the fan shape in plan view high and horizontally, and the scum scraping plate 41 approaches (front side) One side) is held low and level.

  The height will be described in detail. In FIG. 2, the inner peripheral end point of the back side of the guide plate main body 42a is p1, the outer peripheral point is P1, and the inner peripheral end point of the front side of the guide plate main body 42a is q1. Let the point on the outer peripheral side be Q1. Further, two reference circles C and D having the rotation shaft 16 as the center are arranged below the guide plate 42 so as to overlap the arcs on the inner peripheral side and the outer peripheral side of the guide plate 42. A perpendicular line is drawn immediately below P1 and p1, and a point where the outer reference circle C intersects is defined as P0, and a point where the inner reference circle D intersects is defined as p0. Further, a perpendicular line is drawn directly below Q1 and q1, and a point where the outer reference circle C intersects is Q0, and a point where the inner reference circle D intersects is q0. On the back side, the length of the perpendicular P1-P0 on the outer peripheral side is equal to the length of the perpendicular p1-p0 on the inner peripheral side. Further, on the near side, the length of the outer peripheral vertical line Q1-Q0 is equal to the length of the inner peripheral vertical line q1-q0. In addition, the length of the vertical line Q1-Q0 on the near side is shorter than the length of the vertical line P1-P0 on the back side.

  Moreover, the code | symbol 42c in FIG.2 and FIG.5 has shown the valley fold line. When the guide plate 42 is formed, a center point is set on the inner side of the arc on the inner peripheral side with respect to the fan-like metal plate in plan view, and radial valley fold lines 42c are drawn at equal angles from the center point. Then, the plate is valley-folded by pressing along the valley fold line 42c, and the shape viewed from the side with the upper surface side recessed is formed into an R shape. By adjusting the angle of this valley fold, as shown in FIG. 2 or FIG. 3, by making the gradient on the inner circumference side steep and making the gradient on the outer circumference side gentle, finally the one side on the back side is raised, While keeping one side on the near side low, each side becomes horizontal from the inner periphery to the outer periphery, and the guide plate body 42a is formed in a spiral shape. As the number of valley fold lines 42c increases, a spiral plate with a smoother R is formed. The bottom plate 42b is bent so as to be horizontal.

  When the scum scraping plate 41 is rotated by the rotating shaft 16, the scum scraping plate 41 approaches the guide plate 42 as shown in FIG. At this time, the lower end of the scum scraping plate main body 41b is lower than the lower end of the guide plate 42 (height of the bottom plate 42b). Moreover, the lower part of the guide plate main body 42a is submerged to the same depth on both the inner peripheral side and the outer peripheral side. Then, as shown in FIG. 1 (b), the slowly rotating scum scraping plate 41 rubs and moves on the guide plate main body 42a from above the hem plate 42b, thereby causing the scum S floating on the water surface to move. Push it above the surface of the water. Then, the scum S that has passed through the top of the guide plate main body 42a (on the front piece 43a) falls to the scum discharge rod 43 together with a small amount of water.

  Further, as shown in FIG. 1 (c), the scum scraping plate 41 rotates and the lower part thereof falls into the scum discharge rod 43. At this time, the scum S adheres to the scum scraping plate 41 at a position above the front piece 43a. However, the scum S attached on the upper side of the front piece 43a is positioned below the upper part of the back piece 43b. Accordingly, when the scum scratching plate 41 further rotates, as shown in FIG. 1 (d), when the scum scratching plate 41 passes while rubbing the top of the back piece 43b, it adheres to the upper side of the front piece 43a. The scum S that has been scraped is scraped off by the back piece 43 b and is collected in the scum discharge rod 43. When the scum scraping plate 41 further rotates and passes through the scum discharge rod 43 as shown in FIG. 1 (e), the scum scraping plate 41 is in a clean state with no scum S attached.

  As shown in FIG. 4 or 5, the sludge collecting device 3 is a sludge scraping plate that rotates at the bottom of the sedimentation tank body 1 around the motor 14, the bearing 15, the rotating shaft 16, and the rotating shaft 16. 31 and a sludge discharge pipe 32 installed on the floor wall 12 of the settling tank body 1.

  The sludge scraping plate 31 includes a sludge arm 31a that is fixed in a state of extending radially with respect to the rotary shaft 16, and a sludge scraping plate that is fixed to the lower side of the sludge arm 31a at an interval along the sludge arm 31a. It consists of a plate body 31b. The sludge scraping plate body 31b is fixed obliquely with respect to the sludge arm 31a in a plan view so that the sludge at the bottom of the settling tank body 1 is directed to the center.

  When the sludge scraping plate 31 rotates together with the rotation of the rotary shaft 16, the sludge at the bottom is scraped together and collected in the center, and is separated from the sludge discharge pipe 32 by another unit installed outside the sedimentation tank body 1. It is collected in the tank.

  The present invention is not limited to the above embodiment. For example, the upper part of the baffle plate 22 may protrude above the water surface. In this case, the scum scraping plate 41, the guide plate 42, the scum discharge rod 43, and the like are located closer to the outside than the baffle plate 22. The rotary shaft 16 is provided in a radial shape or a fan shape when viewed from the center. In this case, the scum S floating in the baffle plate 22 is collected by a collecting device other than the scum scraping plate 41.

  Further, the overflow basin 51 is not limited to the one in which the outer peripheral piece 54 is separated inward from the peripheral wall 11 of the settling tank body 1, and the outer peripheral piece 54 may be a part of the peripheral wall 11. In this case, the inner peripheral piece 55 serves as an overflow weir.

  In the drawing, the motor 14 is described directly above the rotating shaft 16, and the driving shaft of the motor 14 and the rotating shaft 16 are coaxial. However, the motor 14 is disposed beside the rotating shaft 16, and the driving shaft of the motor 14 is The rotation shaft 16 may be orthogonal to the rotation shaft 16 and the rotation of the driving shaft may be transmitted to the rotation shaft 16 by a transmission mechanism such as a bevel gear.

  The height difference d between the front piece 43a and the back piece 43b of the scum discharge rod 43 may be about 1 to 10 cm, 15 cm or more, and the type of scum S and the settling tank body. It is set according to the capacity of 1.

  In addition, the sedimentation tank body 1 is not limited to a concrete material as long as it functions as a tank, and may be made of stainless steel or the like. Similarly, the overflow basin 51 is not limited to a metal and may be a synthetic resin such as vinyl chloride or FRP as long as it functions as a basin.

DESCRIPTION OF SYMBOLS 1 Precipitation tank body 2 Polluted water inflow device 3 Sludge collection device 4 Scum collection device 5 Sewage discharge device 11 Circumference wall 12 Floor wall 13 Ceiling 14 Motor 15 Bearing 16 Rotating shaft 21 Inflow pipe 22 Baffle plate 23 Support arm 31 Sludge scraping plate 31a Sludge arm 31b Sludge scraper plate body 32 Sludge discharge pipe 41 Scum scraper plate 41a Scum arm 41b Scum scraper plate body 42 Guide plate 42a Guide plate body 42b Bottom plate 42c Valley folding line 43 Scum discharge rod 43a front Piece 43b back piece 43c bottom piece 43d scum scraping member 44 scum discharge pipe 51 overflow overflow 52 sewage discharge pipe 53 bracket 54 outer peripheral piece 55 inner peripheral piece 56 bottom

S scum C reference circle D reference circle d height difference

91 scum discharge rod 91a front piece 91b back piece 91c bottom piece 92 scum scraping plate 93 guide plate

Claims (2)

The scum scraping plate (41) rotates around a rotating shaft (16) provided at the center of the settling tank main body (1), and a guide plate (42) with a gradient disposed near the water surface is scum scraped. after passing under Yadorikiban (41) is rubbed, the scum collecting device for collecting the position to Luz cam discharge gutter (43) on the back side of the scum fall (S) a guide plate (42) (4),
The scum discharge rod (43) includes a front piece (43a) toward which the scum scratching plate (41) approaches, a back piece (43b) from which the scum scratching plate (41) moves away, and the front side. Formed in a U-shaped cross section by a piece (43a) and a bottom piece (43c) connecting the back piece (43b) ,
Bei give a member and scum scraping (43d) at a position higher than than the front piece (43a) a rear side front piece (43a),
A scum recovery device, wherein each upper part of the front piece (43a) and the back piece (43d) is disposed at a position higher than the water surface. The scum recovery device according to claim 1, wherein the scum scraping member (43d) is an upper end portion of the back piece (43b).

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