JP5905335B2 - Sludge scraping machine - Google Patents

Description

  The present invention relates to a sludge scraper that is installed in a sedimentation basin and scrapes sludge accumulated on the bottom of the sedimentation basin and scrapes scum floating on the water surface of the sedimentation basin.

  Conventionally, a long flight board circulates inside the sedimentation basin as the chain travels, and when the flight board travels along the bottom of the sedimentation basin, the sludge accumulated on the bottom of the pond is scraped and the flight board settles. A sludge scraping machine that scrapes scum floating on the water surface when traveling on the water surface of a pond is known (see, for example, Patent Document 1). In these sludge scrapers, as described above, the sludge and scum are scraped while the flight plate travels along the guide rail in the settling basin along with the travel of the chain spanned over the sprocket wheel. It is carried out.

  However, when the water surface of the sedimentation basin is greatly shaken up and down due to long-period vibrations of earthquakes, etc., there are cases where the flight board running on the water surface falls off the guide rails due to severe water level fluctuations.

  In order to prevent the flight board from falling off due to such an earthquake, as shown in Patent Document 1, a countermeasure is provided in which a guard board is provided adjacent to the flight board. This guard plate regulates the upward and lateral movement of the flight plate. This prevents the flight plate from falling even if an earthquake occurs while the flight plate is running, and the chain falls off the sprocket wheel. Is prevented.

  However, on the other hand, the scum floating on the water surface of the settling basin may be captured by the guard plate, and the scum may not be removed by the flight plate and may remain in the settling basin.

JP 2006-326383 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a sludge scraper that can prevent the scum remaining on the water surface of a settling basin from remaining.

  In order to achieve the above-described object, one embodiment of the present invention includes a chain disposed in a settling basin, a flight movable body driven by the chain to scrape sludge in the settling basin, and attached to the flight movable body. The stopper, a pond bottom guide rail that guides the travel of the flight movable body when the flight movable body travels on the bottom of the sedimentation basin, and the flight movable body travels on the water surface of the sedimentation basin. A water surface guide rail that guides the travel of the flight movable body, and a guard rail that regulates the upward and lateral movement of the flight movable body that travels on the water surface guide rail, and the guard rail includes the stopper. The upper and lateral movements of the flight movable body are regulated by hitting the guard rail, and the stopper and the guard rail are controlled. Is a sludge scraper device, characterized in that located below the water surface of the sedimentation basin.

In a preferred aspect of the present invention, there is no structure that crosses the water surface of the settling basin between a side surface of the flight movable body and a side wall of the settling basin.
In a preferred aspect of the present invention, the stopper is detachably attached to the flight movable body.
In a preferred aspect of the present invention, the guard rail is supported by a water surface guide rail support member fixed to a side wall of the settling basin.
In a preferred aspect of the present invention, the stopper and / or the guard rail is made of resin.
In a preferred aspect of the present invention, the guard rail and the water surface guide rail are integrally formed.
In a preferred aspect of the present invention, the guard rail is detachably attached to the water surface guide rail.

  According to the present invention, since the guard rail is disposed below the water surface, there is no member other than the flight movable body that captures the scum floating on the water surface. Therefore, the scum does not remain in the sedimentation basin, and the scum floating on the water surface can be removed by the flight movable body.

It is a figure which shows the outline | summary of the sludge scraping machine which concerns on one Embodiment of this invention. It is a figure which shows a flight movable body. It is a figure which shows a flight movable body and a water surface guide rail. It is the figure which looked at the flight movable body and water surface guide rail which were shown in FIG. 3 from the top. It is sectional drawing which shows the water surface guide rail and guardrail shown in FIG. It is a figure which shows typically the cross section of the flight board shown in FIG. It is a figure which shows the modification of a water surface guide rail and a guardrail. It is the figure which looked at the flight movable body shown in FIG. 7, the water surface guide rail, and the guard rail from the top. It is a figure which shows the other modification of a water surface guide rail and a guard rail. It is a figure which shows the further another modification of a water surface guide rail and a guard rail. It is the figure which looked at the flight movable body shown in FIG. 10, the water surface guide rail, and the guard rail from the top. It is an enlarged view of the water surface guide rail and guardrail shown in FIG. It is a figure which shows the other structural example of a flight movable body, a water surface guide rail, and a guard rail. It is the figure which looked at the flight movable body shown in FIG. 13, the water surface guide rail, and the guard rail from the top. It is a figure which shows typically the cross section of the flight board shown in FIG. It is a figure which shows the modification of a stopper. It is the figure which looked at the flight movable body shown in FIG. 16, the water surface guide rail, and the guard rail from the top. It is a figure which shows the further another structural example of a flight movable body, a water surface guide rail, and a guard rail. It is the figure which looked at the flight movable body shown in FIG. 18, the water surface guide rail, and the guard rail from the top. It is a figure which shows typically the cross section of the flight board shown in FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In addition, in each figure, the same code | symbol is attached | subjected to the member or element which has the same effect | action or function, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a diagram showing an outline of a sludge scraping machine. The sludge scraper is disposed in a settling basin of a sewage treatment plant, for example. This sludge scraper includes a drive device 2, a drive wheel 3, a water surface wheel 4, submersible wheels 5, 6 disposed inside the settling basin 1, and a pair of endless shapes spanned between these wheels. A chain 7 and a flight movable body 8 fixed to the chain 7 at a predetermined interval are provided.

  The pair of chains 7 are arranged in parallel in the sedimentation basin 1, and these chains 7 are circulated by the drive wheel 3 connected to the drive device 2. Along with the circulation of the chain 7, the flight movable body 8 travels inside the sedimentation basin 1.

  When the flight movable body 8 travels on the pond bottom side of the sedimentation basin 1, as shown in FIG. 1, the flight movable body 8 scrapes the sludge accumulated on the pond bottom to the sludge reservoir 1a and travels on the water surface side. Sometimes scum floating on the surface of the water is squeezed to the scum skimmer 9. In order to guide the travel of the flight movable body 8, for example, a resin water surface guide rail 27 and an underwater guide rail 11 that are light and have excellent corrosion resistance are disposed along the side wall of the sedimentation basin 1. Further, a pond bottom guide rail 12 for guiding the travel of the flight movable body 8 is laid on the pond bottom.

  The drive wheel 3 is a sprocket wheel that transmits the rotation to the chain 7. The drive wheel 3 is connected to a sprocket wheel (not shown) that receives power from the drive device 2 via a drive chain 2a. The water surface wheel 4, the underwater wheel 5, and the underwater wheel 6 are all driven wheels. The underwater wheel 5 is configured to be able to adjust the tension of the chain 7 by moving back and forth in the horizontal direction.

  An overflow dam is attached to the scum skimmer 9 so as to be freely opened and closed, and the scum floating on the liquid surface of the sedimentation basin 1 is configured to flow into the trough 9a together with water by the flight movable body 8. . The scum clearance 9 may be a pipe clearance that rotates a pipe having a notch. The sedimentation basin 1 is provided with an overflow weir 14, and the water in the sedimentation basin 1 is discharged beyond the overflow dam 14, so that the water level of the sedimentation basin 1 is kept constant.

  FIG. 2 is a diagram showing the flight movable body 8. As shown in FIG. 2, the flight movable body 8 includes a flight plate (scraping plate) 20 that scrapes sludge and scum, attachment pieces 21 attached to both ends of the flight plate 20, and each attachment piece 21. The first guide shoe 23 is fixed to the upper part, the base 10 is fixed to the lower part of each attachment piece 21, and the second guide shoe 24 is fixed to the lower part of the base 10. The attachment piece 21 and the base 10 may be integrally formed. A chain 7 is fixed to the lower part of the attachment piece 21, and the flight movable body 8 is pulled by the chain 7 and travels.

  A recess 25 is formed on the opposite side of the portion of the attachment piece 21 to which the chain 7 is fixed. The chain guard 16 shown in FIG. 1 is inserted into the recess 25 through a minute gap. The chain guard 16 is disposed so as to surround a part of the drive wheel 3, and the chain guard 16 enters the recess 25 when the flight movable body 8 travels around the drive wheel 3. Yes.

  As a result, even if the chain 7 is about to leave the drive wheel 3 due to an earthquake, the chain guard 16 restricts the movement of the chain 7 and prevents the chain 7 from falling off the drive wheel 3. Here, the chain guard 16 may be disposed on the drive wheel 3 and all the driven wheels 4, 5, 6. By adopting such an arrangement, it is possible to prevent the chain 7 from dropping off at all wheels.

  FIG. 3 is a view showing the flight movable body 8 and the water surface guide rail 27. As shown in FIG. 3, the water surface guide rail 27 is supported by a water surface guide rail support member 30 fixed to the side wall 1 b of the sedimentation basin 1. The water surface guide rail support members 30 are arranged at equal intervals along the water surface guide rail 27. The second guide shoe 24 is fixed to the lower part of the base 10 and is located on the water surface guide rail 27.

  FIG. 4 is a diagram (plan view) of the flight movable body 8 and the water surface guide rail 27 as seen from above. Stoppers 28 are provided at both ends of the flight movable body 8. The stopper 28 has a protrusion 28a that slightly protrudes in the horizontal direction from the side surface 8a of the flight movable body 8 (that is, the side surface 10a of the base 10). The stopper 28 has a U-shape when viewed from above, and is detachably mounted on the base 10 with a screw 35 as a fastener so as to sandwich the attachment piece 21. Since the stopper 28 is detachable, it can be attached to an existing sludge scraper.

  A guard rail 36 that restricts the upward and lateral movement of the flight movable body 8 traveling on the water surface guide rail 27 is provided on the water surface guide rail 27. The water surface guide rail 27 and the guard rail 36 are integrally formed. FIG. 5 is a cross-sectional view showing the water surface guide rail 27 and the guard rail 36. The guard rail 36 is provided adjacent to the stoppers 28 provided at both ends of the flight movable body 8 traveling on the water surface. The water surface guide rail 27 extends horizontally from the first vertical portion 27 a extending downward along the side surface 30 a of the water surface guide rail support member 30 and the upper end of the first vertical portion 27 a, and the lower surface of the second guide shoe 24. And a second vertical portion 27c extending upward from the support portion 27b along the side surface 8a of the flight movable body 8 (that is, the side surface of the attachment piece 21).

  The guard rail 36 is disposed in the vicinity of the stopper 28 when the flight movable body 8 travels on the water surface guide rail 27. The guard rail 36 has a first guard surface 36a located above the protrusion 28a of the stopper 28 and a second guard surface 36b located on the side of the protrusion 28a of the stopper 28. As shown in FIG. 5, the first guard surface 36a is a horizontal surface facing the upper surface of the projection 28a, and the second guard surface 36b is a vertical surface facing the side end of the projection 28a. The lower end of the guard rail 36 is integrally connected to the upper end of the water surface guide rail 27 (that is, the upper end of the second vertical portion 27c). As the material for the water surface guide rail 27, the stopper 28, and the guard rail 36, a resin having high slidability is preferable. Thereby, weight reduction and slidability of the water surface guide rail 27, the stopper 28, and the guard rail 36 are improved.

  By providing the guard rail 36, even if a force is applied in the lateral direction with respect to the flight movable body 8, the stopper 28 hits the second guard surface 36 b of the guard rail 36, and the flight movable body 8 moves further laterally. Cannot be done. Further, when the flight movable body 8 is pushed up by a water flow accompanying an earthquake, the stopper 28 hits the first guard surface 36a of the guard rail 36, and the flight movable body 8 cannot move further upward. Therefore, the flight movable body 8 can continue traveling without falling from the water surface guide rail 27.

  When the chain 7 is driven by the drive wheel 3 and the flight movable body 8 travels on the water surface, the guide shoe 24 slides on the support portion 27b of the water surface guide rail 27, and the guide shoe 24 travels while being guided by the water surface guide rail 27. . When the flight movable body 8 travels on the underwater guide rail 11, the guide shoe 24 slides on the underwater guide rail 11, and the guide shoe 24 travels while being guided by the underwater guide rail 11. The first guide shoe 23 is for traveling by being guided by the pond bottom guide rail 12 when the flight movable body 8 travels on the pond bottom.

  As described above, the flight movable body 8 has two types of guide shoes 23 and 24 for the pond bottom, the water surface, and the underwater, and the flight movable body 8 includes the pond bottom guide rail 12, the underwater guide rail 11, The vehicle travels while sliding on the water surface guide rail 27. The reason why the water surface guide rail 27 and the guide shoe 24 for the underwater guide rail 11 are attached to the end of the flight movable body 8 is to make the water surface guide rail support member 30 extending from the side wall 1b of the settling basin 1 as small as possible. Because.

  Since the guide shoe 23 for the pond bottom guide rail 12 is installed inward from the end of the flight movable body 8, the flight movable body 8 remains on the pond bottom guide rail 12 even once derailed. . Therefore, as long as the chain 7 does not come off the wheel, the flight movable body 8 travels while being pulled by the chain 7. Therefore, if the guide shoe 23 of the derailed flight movable body 8 travels close to the wheel, the guide shoe 23 Automatically returns to the top of the pond bottom guide rail 12, so that no special treatment such as a guard member is required.

  As described above, the water level of the settling basin 1 is kept constant by the overflow weir 14, and the water level is slightly below the upper end of the flight movable body 8 as shown in FIG. The water surface guide rail 27, the guard rail 36, and the stopper 28 are located below the water surface. Furthermore, the water surface guide rail support member 30 is also located below the water surface. As shown in FIG. 3, there is no structure crossing the water surface in the region between the side surface 8 a of the flight movable body 8 and the side wall 1 b of the sedimentation basin 1.

  FIG. 6 is a view schematically showing a cross section of the flight plate 20. As shown in FIG. 6, the cross section of the flight board 20 has a triangular shape, and the inside thereof is formed in a hollow shape. When the flight movable body 8 travels on the water surface, the scum floating on the water surface is captured by the vertical surface 20a of the flight plate 20 and removed.

  In the conventional apparatus, as shown in Patent Document 1 (Japanese Patent Laid-Open No. 2006-326383), a bracket that supports the guard rail is disposed across the water surface, or the guard rail itself is disposed across the water surface. However, with such a configuration, the scum floating on the water surface is caught by the bracket or the guard rail. Further, in the configuration in which the guard rail itself is disposed across the water surface, water may stagnate between the guard rail and the side wall of the settling basin, and scum generated in this region may stay there.

  According to the present invention, since the guard rail 36 is disposed below the surface of the water, it is possible to eliminate the structure between the flight movable body 8 and the side wall 1b of the settling basin. Therefore, the scum floating on the water surface is not captured by the structure, and the scum is removed by the flight movable body 8. When the flight movable body 8 travels on the support portion 27b of the water surface guide rail 27, a water flow is formed between the flight movable body 8 and the side wall 1b, and the scum flows inward. Then, the scum is captured and removed by the subsequent flight movable body. Therefore, scum does not remain in the sedimentation basin 1 and can be removed by the traveling flight body 8 that travels. Furthermore, since the guard rail 36 is configured to be positioned below the water surface, the guard rail 36 can be made smaller than that in Patent Document 1. Therefore, the installation space for the guard rail 36 can be reduced, and the guard rail 36 can be easily installed in a limited installation space. For example, even if there is an obstacle such as a protruding portion (for example, a beam) on the side wall 1b of the settling basin 1, the guard rail 36 can be easily installed.

  FIG. 7 is a view showing a modification of the water surface guide rail 27 and the guard rail 36. In addition, the structure which is not demonstrated in particular is the same as the structure shown in FIG. 3, The duplicate description is abbreviate | omitted. In this example, the stopper 28 is located between the lower surface of the base 10 and the upper surface of the second guide shoe 24. As shown in FIG. 8, the stopper 28 has a plate shape and is sandwiched between the second guide shoe 24 and the base 10 by a screw 35 as a fastener. With such an arrangement, the stopper 28 shown in FIG. 7 is at a lower position than the stopper 28 shown in FIG. Therefore, the position of the guard rail 36 can be further lowered. Also in this example, there is no structure crossing the water surface in the region between the side surface 8a of the flight movable body 8 and the side wall 1b of the settling basin 1.

  FIG. 9 is a view showing another modification of the water surface guide rail 27 and the guard rail 36. As shown in FIG. 9, the first vertical portion 27 a of the water surface guide rail 27 may extend upward along the inner side surface of the second guide shoe 24.

  FIG. 10 is a view showing still another modification of the water surface guide rail 27 and the guard rail 36, and FIG. 11 is a plan view of FIG. FIG. 12 is an enlarged view of the water surface guide rail 27 and the guard rail 36. In addition, the structure which is not demonstrated in particular is the same as the structure shown in FIG. 3, The duplicate description is abbreviate | omitted. In this example, the guard rail 36 is detachably attached to the water surface guide rail 27.

  As shown in FIG. 12, the guard rail 36 further includes an inner wall 36 c and an outer wall 36 d disposed on both sides of the second vertical portion 27 c of the water surface guide rail 27. The outer wall 36d is provided with a screw hole (not shown), and a screw 38 as a fastener is inserted into the screw hole. The second vertical portion 27c of the water surface guide rail 27 is sandwiched between the tip of the screw 38 and the inner wall 36c. By tightening the screw 38, the tip of the screw 38 presses the second vertical portion 27c against the inner wall 36c. As a result, the guard rail 36 is fixed to the water surface guide rail 27. Further, the guard rail 36 can be removed from the water surface guide rail 27 by loosening the screw 38.

  When the flight movable body 8 moves in the lateral direction due to the earthquake, the stopper 28 hits the second guard surface 36b of the guard rail 36, and the flight movable body 8 cannot move further laterally. When the flight movable body 8 is pushed up by the water flow accompanying the earthquake, the stopper 28 hits the first guard surface 36a of the guard rail 36, and the flight movable body 8 cannot move upward any more. Therefore, the flight movable body 8 can continue traveling without falling from the water surface guide rail 27. Also in this example, there is no structure crossing the water surface in the region between the side surface 8a of the flight movable body 8 and the side wall 1b of the settling basin 1.

  13 is a view showing another configuration example of the flight movable body 8, the water surface guide rail 27, and the guard rail 36, and FIG. 14 is a plan view of FIG. In addition, the structure which is not demonstrated in particular is the same as the structure shown in FIG. 3, The duplicate description is abbreviate | omitted. In this example, the flight movable body 8 includes a flight plate 20, a first guide shoe 23 attached to the upper portion of the flight plate 20, and a second guide shoe 24 attached to the lower portion of the flight plate 20. ing. In this example, the attachment piece 21 is not provided, and the chain 7 is fixed to the lower part of the flight plate 20. A recess is formed on the lower surface of the second guide shoe 24, and the upper end of the water surface guide rail 27 is engaged with the recess. In this example, the chain guard 16 shown in FIG. 1 is not provided.

  The guard rail 36 and the water surface guide rail 27 are provided as separate members. The guard rail 36 is fixed on the horizontal surface of the water surface guide rail support member 30 by bolts 51 as fasteners. The stopper 28 is fixed to the side surface 20b of the flight plate 20 with a screw 52 as a fastener so that the protrusion 28a is positioned below the first guard surface 36a of the guard rail 36. The guard rail 36 has a first guard surface 36 a located above the protrusion 28 a of the stopper 28 and a second guard surface 36 b located on the side of the protrusion 28 a of the stopper 28. Also in this example, there is no structure crossing the water surface between the side surface 20b of the flight board 20 and the side wall 1b of the settling basin 1.

  FIG. 15 is a diagram schematically showing a cross section of the flight board 20 shown in FIG. The flight board 20 is made of synthetic wood and has a rectangular cross section. When the flight movable body 8 travels on the water surface, the scum floating on the water surface is captured by the vertical surface 20a of the flight plate 20 and removed.

  16 is a view showing a modification of the stopper 28, and FIG. 17 is a plan view of FIG. As shown in FIG. 17, the stopper 28 has a fitting portion 28b having a U-shape when viewed from above. The fitting portion 28b is provided with a screw hole (not shown), and a screw 55 as a fastener is inserted into the screw hole. The protrusion 28 a of the stopper 28 is fitted into the side end of the flight plate 20 so that the protrusion 28 a of the stopper 28 is positioned below the first guard surface 36 a of the guard rail 36, and the screw 55 is tightened. Thereby, the screw 55 presses the flight plate 20 against the fitting portion 28b of the stopper 28, and the position of the stopper 28 is fixed. The stopper 28 is detachably attached to the flight board 20. Therefore, the stopper 28 can be easily attached to the existing flight board. Also in this example, there is no structure that crosses the water surface in the region between the side surface 20b of the flight board 20 and the side wall 1b of the settling basin 1.

  18 is a view showing another configuration example of the flight movable body 8, the water surface guide rail 27, and the guard rail 36, and FIG. 19 is a plan view of FIG. FIG. 20 is a view schematically showing a cross section of the flight board 20 shown in FIG. For the sake of explanation, a part of the flight board 20 shown in FIG. 19 is shown in section. In addition, the structure which is not demonstrated in particular is the same as the structure shown in FIG. 3, The duplicate description is abbreviate | omitted. The stopper 28 in this example has a plate shape. As shown in FIG. 20, the flight plate 20 has a U-shaped cross-sectional shape, and the stopper 28 is fixed to the inner side surface 20 c of the flight plate 20. Specifically, as shown in FIG. 19, the stopper 28 is fixed to the inner side surface 20 c of the flight plate 20 by a bolt 60 and a nut 61 as fasteners. Also in this example, there is no structure that crosses the water surface in the region between the side surface 20b of the flight board 20 and the side wall 1b of the settling basin 1. When the flight movable body 8 travels on the water surface, the scum floating on the water surface is captured by the vertical surface 20a of the flight plate 20 and removed.

  In any of the examples shown in FIGS. 3 to 19, since the guard rail 36 and the stopper 28 are located below the water surface, there is no member other than the flight movable body 8 that catches the scum floating on the water surface. Therefore, the scum does not remain in the sedimentation basin 1 and the scum floating on the water surface can be removed by the flight movable body 8. Furthermore, since the guard rail 36 is located below the water surface, the guard rail 36 can be made small. Thereby, the installation space of the guardrail 36 can be made small. Therefore, the guardrail 36 can be easily installed in a limited installation space. For example, even if there is an obstacle such as a protruding portion (for example, a beam) on the side wall 1b of the settling basin 1, the guard rail 36 can be easily installed.

  Although the embodiments of the present invention have been described so far, the present invention is not limited to the above-described embodiments, and may of course be implemented in various forms within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 1 Sedimentation basin 1a Sludge storage part 1b Side wall 2 Drive apparatus 3 Drive wheel 4 Water surface wheel (driven wheel)
5,6 Underwater wheel (driven wheel)
7 Chain 8 Flight movable body 9 Scum skimmer 10 Base 11 Underwater guide rail 12 Ikeboshi guide rail 14 Overflow weir 16 Chain guard 20 Flight plate 21 Attachment piece 23 Guide shoe for pond bottom guide rail 24 Guard shoe and guide shoe for underwater guide rail 25 concave portion 27 water surface guide rail 27a first vertical portion 27b support portion 27c second vertical portion 28 stopper 28a projection portion 28b fitting portion 30 water surface guide rail support members 35, 38, 52, 55 screw 36 guard rail 36a first Guard surface 36b Second guard surface 36c Inner side wall 36d Outer side wall 51, 60 Bolt 61 Nut

Claims (7)

A chain placed in the settling pond;
A flight movable body driven by the chain and scraping sludge in the sedimentation basin,
A stopper attached to the flight movable body;
A pond bottom guide rail that guides the travel of the flight movable body when the flight movable body travels along the bottom of the sedimentation basin;
A water surface guide rail that guides the travel of the flight movable body when the flight movable body travels on the water surface of the settling basin;
A guard rail that regulates the upward and lateral movements of the flight movable body traveling on the water surface guide rail,
The guard rail regulates the upward and lateral movement of the flight movable body by the stopper hitting the guard rail,
The stopper and the guard rail are located below the water surface of the settling basin.   The sludge scraper according to claim 1, wherein there is no structure crossing the water surface of the settling basin between a side surface of the flight movable body and a side wall of the settling basin.   The sludge scraper according to claim 1 or 2, wherein the stopper is detachably attached to the flight movable body.   The sludge scraper according to any one of claims 1 to 3, wherein the guard rail is supported by a water surface guide rail support member fixed to a side wall of the settling basin.   The sludge scraper according to any one of claims 1 to 4, wherein the stopper and / or the guard rail is made of resin.   The sludge scraper according to any one of claims 1 to 5, wherein the guard rail and the water surface guide rail are integrally formed.   The sludge scraper according to any one of claims 1 to 5, wherein the guard rail is detachably attached to the water surface guide rail.

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