JP2006247536A - Sedimentation basin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sedimentation basin in which sludge at a basin bottom can surely be scraped while promoting sedimentation of suspension components and thereby which can attain increase of treatment capability and improvement of treated water quality. <P>SOLUTION: A large number of planar bodies 22 are hooked at definite intervals to a chain 19 which is arranged so as to circulate between a bottom part and an upper part of the sedimentation basin 11 while being guided by a plurality of sprockets 16, 17, 18. When passing the bottom part of the sedimentation basin, the planar bodies 22 are in a state where the sludge precipitated at the basin bottom is scraped toward a sludge discharging pit 14 and when passing the upper part of the sedimentation basin, the planar bodies 22 are in an inclined state toward a horizontal surface and function as a sedimentation promoting plate for promoting sedimentation of the suspension components. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sedimentation basin, and more specifically, has a function of scraping sludge settled on the bottom of the pond to a sludge pit and a function of promoting sedimentation of suspended components, and is particularly applicable to sewage sedimentation treatment. Regarding possible sedimentation ponds.

Conventionally, the sedimentation accelerating plate composed of an inclined plate or an inclined tube is provided at the upper part of the sedimentation basin to promote the sedimentation of the suspended components. In the past, the sludge that has settled on the sewage has been raked into the sludge pit (see, for example, Patent Document 1).
JP 2001-239107 A

  However, in the conventional sedimentation basin, when both the sedimentation promotion plate and the scraping machine are installed, the sedimentation promotion plate occupies the space above the sedimentation tank. However, there is a problem that the maintenance of the scraper can be performed only with the water drained from the settling tank. For this reason, in the field of sewage treatment that contains a large amount of suspended components to be settled and separated, both the sedimentation promotion plate and the scraper have not been installed in the sedimentation basin.

  Accordingly, the present invention provides a sedimentation basin that can surely carry out sludge scraping of the pond bottom while promoting sedimentation of suspended components, and can increase the treatment capacity and improve the quality of treated water. It is an object.

  In order to achieve the above object, the sedimentation basin of the present invention is guided by a plurality of rotating guide members, and is arranged to circulate between a position along the bottom of the sedimentation basin and a position passing through the top of the sedimentation basin. A traction member, a plurality of plate-like bodies spanned across the plurality of traction members at regular intervals, and drive means for moving the traction member in a constant direction. When passing through the bottom of the pond, the sludge settled on the bottom of the pond is scraped toward the sewage pit, and when passing through the upper part of the settling basin, it becomes a state of a sedimentation promoting plate that promotes sedimentation of suspended components.

  Further, in the sedimentation basin of the present invention, the plate-like body is provided such that a tip portion thereof is inclined rearward with respect to a traveling direction of the traction member with respect to a base portion attached to the traction member, and is adjacent to the plate. It is characterized in that the base portion and the distal end portion of the cylindrical body are provided so as to overlap in a plan view.

  Further, the plate-like body is characterized in that the plate-like body on the sedimentation basin inflow side is exposed on the water surface when passing through the upper part of the sedimentation basin, and further, the sedimentation is performed above the water surface of the sedimentation basin. It has a plate-like body cleaning means for injecting cleaning water toward the plate-like body exposed on the water surface of the pond.

  According to the sedimentation basin of the present invention, it is possible to promote the sedimentation of suspended components with a large number of plates passing through the upper part of the sedimentation basin, and the sludge is scraped into the waste mud pit with the plate passing through the bottom of the sedimentation basin. Can be sent. Furthermore, the precipitation promoting effect can be increased by setting the base and tip of adjacent plate-like bodies to overlap each other in plan view.

  In addition, by exposing a part of the plate-like body from the surface of the water, the maintenance of the plate-like body can be easily performed, and the plate-like body is automatically provided by providing a plate-like body cleaning means for injecting cleaning water. Can be cleaned.

  Therefore, one device has the functions of both a conventional sedimentation promoting plate and a scraping machine, so that the sedimentation efficiency can be improved and the sedimentation promoting plate and the scraping machine can be installed separately. Compared to, equipment costs can be reduced.

  FIG. 1 is a cross-sectional view showing an embodiment of a sedimentation basin according to the present invention, FIG. 2 is a front view of the main part showing the state of attachment of the plate-like body to the chain, FIG. It is sectional drawing of the principal part which shows an example of a plate-shaped body washing | cleaning means. The sedimentation basin 11 is provided with a raw water inflow portion 12 at one end in the longitudinal direction and a treated water outflow portion (trough) 13 at the upper end of the other end, and a drainage pit (a waste mud hopper) at the bottom of the inflow portion. 14 is provided. Further, a beam 15 for installing a device (not shown) for collecting the scum floating on the water surface and preventing the scum from flowing to the treated water outflow portion 13 side is provided in the middle upper part of the sedimentation basin 11. It has been.

  In the settling basin 11, a plurality of, usually a pair of endless, sprockets 16, 17, 18, which are one of three sets of rotation guide members provided on both sides of the settling basin 11 in the width direction, are provided. A chain 19 as a pulling member is attached. Of the three sets of sprockets, two sets of sprockets 16 and 17 are respectively arranged on the inflow side pond bottom and the outflow side pond bottom, and one set of sprockets 18 is arranged on the water surface portion on the inflow side upper part. . A sprocket 18 disposed at the upper part of the inflow side is connected to a motor 20 as a driving means by a driving chain 21. Accordingly, the chain 19 is guided by the sprockets 16, 17 and 18 and driven by the motor 20 so that the position along the bottom of the settling basin 11 and the position passing through the top of the settling basin 11 are in the direction of the arrow in FIG. It will be in a circulating state.

  A large number of plate-like bodies 22 are wound around the outer periphery of the chain 19 at regular intervals. The plate-like body 22 has a length corresponding to the width dimension of the settling basin 11 and is formed in a plate-like shape on the attachment portion 19b provided on the link plate 19a in the chain 19, as shown in FIGS. The base portion 22a of the body 22 is fixed, and the tip portion 22b side is provided so as to incline backward with respect to the traveling direction of the chain 19 with respect to the base portion 22a. Moreover, the front-end | tip part 22b is bent so that it may become perpendicular | vertical to a pond bottom face, when passing the bottom part of the sedimentation basin 11, and it is formed so that sludge can be scraped up reliably.

  When each plate-like body 22 is pulled by the chain 19 and passes through the bottom of the settling basin 11, the sludge settled on the bottom of the pond is scraped toward the waste mud pit 14, and when passing through the top of the settling basin 11, Similarly to the conventional inclined plate and inclined tube, the base 22a and the tip 22b of the adjacent plate-like body 22 are formed so as to overlap each other in plan view while being inclined with respect to the horizontal plane. That is, as the chain 19 guided by the sprockets 16, 17, and 18 gradually moves, the bottom of the sedimentation basin 11 exhibits a sludge scraping function equivalent to that of a conventional chain flight sludge scraper. In the upper part of 11, a sedimentation promoting function equivalent to or higher than that of a conventional sedimentation promoting plate such as a tilted plate or a tilted tube is exhibited.

  Further, at a portion passing through the sprocket 18 provided at the upper inflow side of the settling basin 11, at least one plate-like body 22 is formed so as to be exposed on the water surface, and the raw water inflow portion 12 is formed. The raw water that has flowed into the sedimentation basin 11 from above does not pass directly above the plate 22 toward the treated water outflow portion 13.

  The installation angle of the plate-like body 22 is set to 60 degrees or more with respect to the horizontal plane in order to prevent the suspended component (sludge) from accumulating on the upper surface in the conventional inclined plate or inclined tube. In the present invention, since the plate-like body 22 is inverted as the chain 19 advances, the accumulation of suspended components on the upper surface of the plate-like body is hardly a problem, so the installation angle of the plate-like body 22 with respect to the horizontal plane is 60 degrees. The following can be set.

  Here, it is said that the separation efficiency in the settling basin 11 is governed by the water area load Q / A, which is the ratio of the settling basin area (separation area) A to the treated water amount Q, but the installation effect of the settling promotion plate is Theoretically, the separation area is increased by the projected area. If the width of one sedimentation promotion plate is W, the height is H, the installation angle with respect to the horizontal plane is θ, and the effective number is N, the increase S0 of the separation area by the sedimentation promotion plate is S0 = W × H ÷ cos θ × N It becomes. Therefore, the separation area can be increased by reducing the installation angle θ of the settling promotion plate, and the settling efficiency can be improved with the same number (area) of settling promotion plates, thereby reducing the equipment cost. However, since the installation angle of the plate-like body 22 may be inconvenient such as the flow area between the plate-like bodies becomes narrow if it is too small, it is usually set to 10 degrees or more with respect to the horizontal plane. Is preferred.

  Further, as a plate-like body cleaning means for injecting cleaning water toward the plate-like body 22 exposed on the water surface in the vicinity of the position where the plate-like body 22 is exposed on the water surface above the water surface of the sedimentation basin 11. A spray nozzle 23 is provided. The plate-like body 22 can be easily cleaned by spraying cleaning water continuously or at an appropriate interval from the spray nozzle 23. This is particularly effective in the case of sewage treatment where biological slime and algae are a concern.

  In this embodiment, the chain is guided in a triangular shape using three sets of sprockets, but the chain can also be guided in a quadrangular (trapezoidal) shape using four or more sets of sprockets. Further, the entire plate-like body may be disposed in water, or the interval between the plate-like bodies may be widened so that the base portion and the tip portion of the adjacent plate-like bodies do not overlap in plan view.

  In addition, sprockets and chains are used as a combination of a rotating guide member and an endless pulling member, but any member can be used as long as it can pull a plate-like body such as a combination of a pulley and a wire, or a drum and a belt. it can.

  Further, the above plate-like body cleaning means can be used as long as it can wash the plate-like body by jetting cleaning water, and a part of the treated water can be used as the washing water. In addition, since the existing sedimentation basin can be easily modified, the treatment capacity (treatment water amount) can be increased, and the treatment water quality can be improved when the treatment water amount is not changed.

It is sectional drawing which shows one example of a sedimentation basin of this invention. It is a front view of the principal part which shows the attachment state of the plate-shaped object to a chain. It is a top view of the principal part similarly. It is sectional drawing of the principal part which shows an example of a plate-shaped body washing | cleaning means.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Sedimentation basin, 12 ... Raw water inflow part, 13 ... Treated water outflow part, 14 ... Waste mud pit, 15 ... Beam, 16, 17, 18 ... Sprocket, 19 ... Chain, 19a ... Link plate, 19b ... Attachment part, DESCRIPTION OF SYMBOLS 20 ... Motor, 21 ... Drive chain, 22 ... Plate-shaped body, 22a ... Base part, 22b ... Tip part, 23 ... Spray nozzle

Claims (4)

  A plurality of endless traction members, which are guided by a plurality of rotating guide members and arranged to circulate between a position along the bottom of the settling basin and a position passing through the top of the settling basin; A plurality of plate-like bodies that are stretched over and a driving means that moves the pulling member in a certain direction, the plate-like body drains sludge that has settled on the bottom of the pond when passing through the bottom of the pond. A sedimentation basin characterized in that it becomes a state of a sedimentation accelerating plate that promotes the sedimentation of suspended components when it passes through the upper part of the sedimentation basin.   The plate-like body is provided such that a tip portion thereof is inclined rearward with respect to a traveling direction of the traction member with respect to a base portion attached to the traction member, and a base portion and a tip portion of adjacent plate-like bodies are provided. The sedimentation basin according to claim 1, wherein the sedimentation basin is provided so as to overlap in a plan view.   The sedimentation basin according to claim 1 or 2, wherein when the plate-like body passes through the upper part of the sedimentation basin, the plate-like body on the sedimentation basin inflow side is exposed on the water surface.   The sedimentation basin according to claim 3, further comprising plate-like body cleaning means for injecting washing water toward the plate-like body exposed on the water surface of the sedimentation basin above the water surface of the sedimentation basin. .

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