JP4379086B2 - Anti-clogging device - Google Patents

Description

The present invention relates to a clogging prevention device used for a pumping system or the like used for mountain excavation work .

  In the mountain retaining method, in which a retaining wall is constructed in the ground and the interior is excavated, a pumping well (deep well) is provided in order to prevent boiling and padding on the root surface due to the influence of groundwater during excavation. The groundwater level is lowered by pumping up the groundwater.

  In this case, the pumped-up groundwater is recondensed by a condensate well (recharge well) in order to prevent ground subsidence and reduce discharge into the sewer. In such excavation method, the excavated earth and sand at the time of construction may flow into the pumping well, so that the pumping or condensing well is clogged, and the function of pumping or condensing is reduced or stopped. was there.

  Thus, for example, Patent Document 1 discloses a means for inserting a washing machine having a submersible pump into the well and sucking and removing clogged substances adhering to the casing of the well with a submersible pump.

  Further, in Patent Document 2, dry ice is introduced into a well casing and gas is generated by sublimating the dry ice, and the slits of the casing are washed with a group of gas bubbles to prevent clogging substances. A removal means is disclosed.

However, such conventional means for removing clogging substances have the following technical problems.
JP 7-216942 A JP-A-1-214626

  In other words, the clogging substance removing means disclosed in Patent Documents 1 and 2 requires that the washing machine be inserted and dry ice inserted every time clogging occurs, which is cumbersome. In addition, even if the clogging substances are removed, it is difficult to completely restore the original discharge capacity, and the capacity of the pumping and condensate wells is often short-lived.

The present invention has been made in view of such conventional problems, and the object of the present invention is to provide a clogging capable of maintaining the function of the filter unit for a long period of time without performing troublesome work. It is to provide a prevention device.

In order to achieve the above object, the present invention comprises a cylindrical hollow tube and a cylindrical filter provided at the center of the hollow tube, and the inner periphery of the hollow tube An annular space is formed between the outer periphery of the filter portion and the outer periphery of the filter portion, and drainage water containing construction-generated water, rainwater, groundwater, etc. in the annular space is discharged from the tangential direction to the horizontal line. Introducing so that a swirling flow that faces downward occurs, the foreign matter having a large weight in the discharged water is dropped downward by the centrifugal force and the gravity difference, and the foreign matter having a small weight is levitated upward, and By passing through the filter part, the solid content in the discharged water was filtered, and the treated water after filtration was taken out from the inner peripheral side of the filter part.
According to the clogging prevention device configured in this way, before the drained water permeates the filter part, it is introduced into the annular space so that a swirling flow that faces downward from the tangential direction to the horizontal line occurs, The foreign substance having a large weight in the discharged water is dropped downward by the centrifugal force and the gravity difference, and the foreign substance having a small weight is levitated upward and separated, so that the function of the filter unit can be maintained for a long time.

The hollow tube body is provided on the upper end side, and is a reservoir for the small foreign matter that is lighter than water such as air or oil, and the reservoir for the large foreign matter that is provided on the lower end side and is heavier than water such as earth and sand. An electromagnetic valve that opens at each set time .

  The filter portion may be configured by cylindrical inner and outer screens arranged concentrically at a predetermined interval, and a granular filter material filled between the inner and outer screens.

The clogging prevention device according to the present invention can maintain the function of the filter portion for a long period of time.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

FIGS. 2 to 8 show an embodiment of the clogging prevention device according to the present invention. In this embodiment, the clogging prevention device according to the present invention is applied to a pumping system used for mountain excavation work. . FIG. 1 is an overall configuration diagram of a pumping system.

  The pumping system of the present embodiment is used for a mountain retaining excavation work for excavating the interior of the retaining wall 10 to a predetermined depth after the retaining wall 10 is constructed to a predetermined depth in the ground E. The mountain retaining wall 10 is formed of, for example, a steel sheet pile or an underground continuous wall.

  In such excavation work, the pumping well (deep well) 12 is provided and the groundwater is pumped up in order to prevent boiling and board blistering on the root surface due to the influence of groundwater when excavating the ground E. The groundwater level is decreasing. In this case, the groundwater that has been pumped is subjected to condensate by a condensate well (recharge well) 14 in order to prevent ground subsidence and reduce discharge into the sewer.

  The pumping well 12 includes a casing pipe 12a, a filter layer 12b, and a pumping pump 12c. On the lower end side of the casing pipe 12a, a strainer portion 12d capable of passing the collected discharged water W1 to the inner side is provided. The strainer unit 12 may employ a wound type strainer having a structure similar to that of the filter unit 24 of the clogging prevention device 20 to be described later and wound with a metal wire.

  The pumping well 12 having such a component is a casing provided with a strainer portion 12d, for example, by using a percussion excavator to form a hole to a predetermined depth in the ground E, performing slime treatment. Insert the pipe 12a into the drilling hole, fill the filter material such as dredged sand between the drilling hole and the casing pipe 12a to form the filter layer 12b, and install the pumping pump 12c in the casing pipe 12a Built in.

  On the other hand, the condensate well 14 includes a casing pipe 14a, a filter layer 14b, and a cleaning submersible pump 14c. A strainer portion 14 d through which water passes to the outside is provided at the lower end of the casing pipe 14 a, and the strainer portion 14 d has the same structure as the strainer portion 12 d of the pumping well 12.

  The condensate well 14 having such components is constructed by a method substantially similar to the pumping well 12 described above. In this case, in the condensate well 14, the filter layer 14b is formed only at a portion where the groundwater flow W2 flows, that is, at the outer periphery of the lower end of the casing pipe 14a, and an annular seal portion 14e is provided on the upper portion. And the sealing material 14f which blocks | prevents inflow of groundwater is filled into the upper part side of the seal part 14e between the drilling hole and the casing pipe 14a.

  The structures of the pumping well 12 and the condensate well 14 as described above are not exceptional as a pumping system in ground excavation work, but the system of the present embodiment has the following remarkable features.

  That is, on the above-described pumping well 12 side, along with excavation of the ground E, drainage water W1 containing construction water, rainwater, groundwater and the like mixed with excavated earth and sand is collected, and this is pumped by the pumping pump 12c. Then, it is thrown into the condensate well 14 and returned from the strainer portion 14d of the condensate well 14 to the groundwater flow W2.

  However, when such discharged water W1 is directly introduced into the condensate well 14, the strainer portion 14d is clogged. Therefore, in this embodiment, the clogging prevention device 20 for separating and removing foreign matters such as earth and sand in the discharged water W1 is installed on the ground portion in the path through which the discharged water W1 is introduced into the condensate well 14.

  Details of the clogging prevention device 20 are shown in FIGS. As shown in FIGS. 2 and 3, the clogging prevention device 20 shown in these drawings includes a hollow tube body 22 and a cylindrical filter portion 24 provided in the tube body 22. In addition, the clogging prevention apparatus 20 of a present Example is drive | operated in the form with which water was filled inside.

  The hollow tube body 22 includes a tube body 22a having both ends opened, a lower lid portion 22b flanged to the lower end of the tube body 22a, and an upper lid portion 22c flanged to the upper end of the tube body 22a. The stay 23 is supported in an upright state.

  As shown in FIG. 3, a disc-shaped lower end plate 22d is sandwiched between the flange joint portion between the tube body 22a and the lower lid portion 22b, and the flange joint portion between the tube body 22a and the upper lid portion 22c is A disc-shaped upper end plate 22e is sandwiched. Each end plate 22d, 22e is interposed so as to partition the inside up and down.

  In the lower end plate 22d, as shown in FIG. 6, a plurality of elongated holes 22f having a divided structure are formed through the same circle. As shown in FIG. 4, a plurality of circular holes 22g are formed through the upper end plate 22e at predetermined intervals along the circumferential direction on the same circle.

An inlet 22h for introducing the discharged water W1 is fixed on the side surface of the pipe body 22a. Further, the upper lid portion 22c is provided with a lead-out port 22i that leads out treated water W3 described later, and an open / close valve 22n is attached to the lead-out port 22i.

  The cylindrical filter portion 24 includes cylindrical inner and outer screens 24a and 24b arranged concentrically at a predetermined interval, and a granular filter material 24c filled between the inner and outer screens. Have.

  Details of the inner and outer screens 24a and 24b are shown in FIGS. The inner screen 24a shown in FIG. 7 includes a pair of cylindrical bodies 240a, a plurality of rods 241a, and wires 242a.

  The pair of cylindrical bodies 240a are disposed at the upper and lower ends, and both ends of the plurality of rods 241a are welded between the cylindrical bodies 240a. The rods 241a are arranged at predetermined intervals along the outer periphery of the cylindrical body 240a. The wire 242a is wound along the outer periphery of the rod 241a, and a predetermined gap (slit) is provided between the surfaces of adjacent portions in the vertical direction, and the opening of the screen 24a is the size of this gap. The rate is determined.

  The outer screen 24b shown in FIG. 8 is composed of a pair of cylindrical bodies 240b, a plurality of rods 241b, and wires 242b having a diameter larger than that of the inner screen 24a, and is substantially the same as the inner screen 24a. It has. The granular filter material 24c is selected from, for example, No. 1 cinnabar, No. 2 cinnabar, No. 3 cinnabar, etc., having a predetermined particle size and particle size distribution.

  Here, the slit interval of the inner and outer screens 24a and 24b is 0.5 mm smaller than the interval of the strainer portion 14d of the condensate well 14 if the interval is 1.0 to 1.5 mm, for example. The particle size of the granular filter material 24c may be 2 mm, for example, to prevent the outflow.

  As shown in FIG. 2, the filter unit 24 having such a configuration is such that the inner and outer screens 24a and 24b are concentrically arranged and the granular filter material 24c is filled between the inner and outer screens 24a and 24b. Therefore, it is installed in the hollow tube body 22.

  In this case, the inner and outer screens 24a and 24b of the filter portion 24 are placed on the lower end plate 22d, and the upper end of the outer screen 24b is positioned and sandwiched so as to contact the lower surface of the upper end plate 22e. ing. The upper end side of the inner screen 24a extends through the upper end plate 22d and communicates with the outlet 22i.

  In the above configuration, the clogging prevention device 20 has an annular space 26 formed between the inner periphery of the hollow tube 22 and the outer periphery of the filter portion 24. Further, the upper end side of the hollow tube body 22 is defined by the upper end plate 22 and the upper lid portion 22b, and communicates with the annular space 26 through the circular hole 22g, and water such as air, oil, and suspended matter. A first reservoir 28 of lighter lightweight material is formed. In this case, the circular hole 22g has a swirling flow having a predetermined flow velocity in the annular space 26 below the circular hole 22g, and thus the reverse flow of the lightweight substance accommodated in the first reservoir 28 is prevented.

  Furthermore, the lower end side of the hollow tube 22 is defined by a lower end plate 22d and a lower lid portion 22b, communicates with the annular space 26 through a long hole 22f, and is made of metal powder such as earth and sand or iron. A second reservoir 30 of a heavy substance heavier than the water is formed. The long hole 22f has a large opening in order to increase the collection efficiency as much as possible because there is little possibility of heavy substances flowing back.

  Each reservoir 28, 30 is provided with an electromagnetic valve 32 communicating with the inside at the lower or upper lid portions 22b, 22c. The electromagnetic valve 32 opens each reservoir 28, 30 every set time. The inner sand is discharged to the outside.

  In addition, the part shown with the code | symbol 33 in FIG. 1 is the earth and sand reservoir which accommodates the earth and sand etc. which are discharge | released by opening of the solenoid valve 32. By providing such an electromagnetic valve 32, maintenance of the clogging prevention device 20 can be automatically performed.

  As shown in FIG. 1, the clogging prevention device 20 has one end of the hose 12e connected to the pumping pump 12c connected to the inlet 22h, and one end of the discharge hose 34 connected to the outlet 22i. The other end of the discharge hose 34 is inserted into the condensate well 14.

  1 is a sensor for driving and stopping the cleaning submersible pump 14c, and the water level W in the condensate well 14 is installed, for example, about 2 m below the ground line. When it is raised to the position of the upper sensor 36, the pump 14c is driven to discharge the water in the condensate well 14 into the sewage, and the water level W is lowered to be set at about 1 to 2 m above the discharge hose 34. If the position of the sensor 36 is still lowered, the driving of the pump 14c is stopped.

  In the pumping system configured as described above, when the discharged water W1 is collected in the pumping well 12, it is pumped and introduced into the clogging prevention device 20 via the pumping pump 12c.

In this case, the discharged water W1 flows into the annular space 26 in the hollow tube body 22 through the introduction port 22h . At this time, the introduction port 22h is provided on the outer periphery of the hollow tube body 22. Therefore, as shown in FIG. 5, the discharged water W1 flows in a layered manner in the annular space 26 so as to rotate many times.

  In order to effectively cause a swirl flow in the annular space 26, the introduction port 22h introduces the discharged water W1 into the annular space 26 from a tangential direction in contact with the outer peripheral edge, and FIG. It is desirable to attach so that the central axis may be directed downward by a predetermined angle with respect to the horizontal line.

  Due to such turning, foreign matter such as heavy earth and sand is separated from the water and falls downward due to the difference in centrifugal force, and foreign matter such as light air and the like is separated from the water and To surface. In the course of such a swirling flow, a part of the discharged water W1 passes through the filter part 24 and reaches the inner screen part 24a. At this time, it is filtered by the filter material 24c, And so on.

  A heavy substance heavier than water such as earth and sand separated from the discharged water W1 falls downward and is stored in the first reservoir 28. Further, a lighter material that is lighter than water, such as air or oil, separated from the discharged water W <b> 1 moves upward and is accommodated in the second reservoir 30. The foreign substances accommodated in the pool portions 28 and 30 are discharged to the outside by driving the solenoid valve 32 when a predetermined time has elapsed.

  On the other hand, the filtered treated water W3 that has passed through the filter portion 24 and reached the inner screen portion 24a is introduced into the condensate well 14 through the outlet 22i and the discharge hose 34, and is applied to the strainer portion 14d. Is returned to the groundwater flow W2.

  Now, according to the pumping system used for the mountain excavation work constructed as described above, clogging that separates and removes foreign matters such as earth and sand in the drainage water W1 in the path for feeding the drainage water W1 into the condensate well 14 is performed. Since the prevention device 20 is installed on the ground, the condensate well 14 is not clogged.

  If the condensate well 14 is not clogged, it is not necessary to perform a troublesome cleaning operation, and the capacity of the condensate well 14 can be maintained for a long period of time. Since foreign matter such as earth and sand separated and removed by the clogging prevention device 20 is installed on the ground, it can be operated without affecting the ground excavation work and can be easily maintained.

  Furthermore, in the case of the present embodiment, the following effects can be expected. That is, in general, groundwater has a small amount of dissolved oxygen, a steel pipe casing pipe 14a is used for the condensate well 14, and the strainer portion 14d is formed of a metal winding. When the amount of dissolved oxygen increases, even if foreign matters such as earth and sand are removed, there is a concern that the function may be shortened due to oxidation of the strainer portion 14d.

However, as in the present embodiment, the clogging prevention device 20 is connected to the hose 12e of the pumping pump 12c, one end of the discharge hose 34 is connected to the discharge port 22i, and the other end of the discharge hose 34 is connected to the condensate well. 14 is opened to a portion deeper than the water level W, so that the portion that is open to the outside air is greatly reduced until the discharged water W1 is pumped up and condensed, so an increase in dissolved oxygen is avoided. Is done.

  When dissolved oxygen increases, the activity of bacteria and microorganisms changes, and if this is reconstituted into groundwater, it may lead to contamination of groundwater, but as in this example, if the increase in dissolved oxygen is prevented, It is also preferable for environmental measures.

  In order to effectively exhibit such an effect, when the submersible pump 14c for cleaning is used, the sensor 36 shown in FIG. 1 is installed, and the water level W drops below the discharge hose 34. Need to be prevented.

The clogging prevention device according to the present invention can prevent clogging of the filter part and maintain its function for a long period of time.

It is a whole block diagram of the pumping system used for the mountain excavation construction to which the clogging prevention device concerning the present invention is applied. It is an external view of the clogging prevention apparatus shown in FIG. It is sectional drawing of the clogging prevention apparatus shown in FIG. It is an AA arrow directional view of FIG. It is a BB line arrow directional view of FIG. FIG. 4 is a view taken along the line CC in FIG. 3. FIG. 4 is a detailed view of the inner screen shown in FIG. 3. FIG. 4 is a detailed view of the outer screen shown in FIG. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Mountain retaining wall 12 Pumping well 14 Condensate well 20 Clogging prevention device 22 Hollow tube body 24 Filter part 26 Annular space 28 First reservoir part 30 Second reservoir part 32 Solenoid valve

Claims (3)

A cylindrical hollow tube, and a cylindrical filter provided at the center of the hollow tube,
An annular space is formed between the inner periphery of the hollow tube and the outer periphery of the filter part,
In the annular space, drainage water containing construction generated water, rainwater, groundwater, etc. is introduced into the annular space so that a swirling flow that faces downward from the tangential direction to the horizontal line occurs,
The foreign matter having a large weight in the discharged water is dropped downward by centrifugal force and the difference in gravity, the foreign matter having a small weight is lifted upward, and the solid matter in the discharged water is allowed to pass through the filter unit. Filtered,
A clogging prevention device, wherein treated water after filtration is taken out from an inner peripheral side of the filter unit. The hollow tubular body is provided on the upper end side, and is a reservoir of a small foreign substance that is lighter than water such as air or oil,
Provided at the lower end side, and having a large foreign substance reservoir heavier than water such as earth and sand,
The clogging prevention device according to claim 1, wherein an electromagnetic valve that opens at each set time is provided in each reservoir. The filter unit includes cylindrical inner and outer screens arranged concentrically at a predetermined interval, and a granular filter material filled between the inner and outer screens. The clogging prevention device according to claim 1 or 2.

Images