JP6715407B2 - Sand collector in a sand basin - Google Patents

Description

The present invention relates to a sand collecting device in a sand basin.

In the sewage treatment facility, sewage such as rainwater and sewage collected in an inflow conduit by a sewer pipe is made to flow into a sand basin by opening a dam device. At the uppermost stream side of the sand basin, first, the screen is used to remove impurities, and the sand is allowed to settle in the sand basin during the slow flow, and then the dam device is closed to stop the inflow of sewage into the sand basin. Then, the sewage from which the sand has been separated is discharged by a drainage pump installed in a pump well located downstream of the sand basin and transferred to a terminal treatment plant or the like to make the sand basin drained. On the other hand, low-pressure sand collection is performed by injecting low-pressure water from the nozzle group toward the sloping bottom surface of the sand basin, causing the sand accumulated on the bottom of the sand basin to flow, and collecting the drifted sand in the sand collecting pit of the sand basin. A method sand collector is used.

After closing the dam device, the sand collecting device draws out the water in the sand basin with a drainage pump and drains it.When the water level in the sand basin drops to a specified height, the drainage pump is stopped and the bottom of the sand basin Low pressure water is discharged from a nozzle provided at the upper end of the main trough, which is formed so that the sand collecting pit side is deepest parallel to the water flow direction. Subsequently, water is jetted toward the inclined bottom surface of the sand basin from a group of nozzles provided along both side walls of the sand basin. As a result, the sand accumulated on the bottom surface of the sand basin is poured into the main trough, and further poured from the main trough into the sand collecting pit to be collected. The sand collected in the sand collecting pit is pumped out together with water by a sand pump installed in the sand collecting pit and removed.

The sand pump automatically starts operation when the water surface at the sand collecting pit installation position reaches a predetermined high water level, and when the water surface reaches a predetermined low water level in the sand collecting pit, it automatically operates. It also has the function of stopping the sand basin and keeping it in a drainage state.

Patent Document 1 discloses a low-pressure sand collecting method and device for collecting sand by injecting low-pressure water from a nozzle onto the bottom of a sand basin in a drained state. This low-pressure sand collecting method has an advantage that a remarkably lower pressure of about 1/200 is sufficient than the discharge pressure of the high-pressure sand collecting method in which high pressure water is jetted into water from a nozzle in a non-drained state.

In the above sand collecting device, in order to be able to use a small water supply pump for supplying water to the nozzle, and to reduce the load on the sand pump, at the bottom of the sand basin at least on one side of the main trough. It is divided into a plurality of regions, and the fuel is sprayed in order from the region near the sand collecting pit to the region farther from the sand collecting pit for a fixed time.

In order to efficiently collect sand in each area, a nozzle header in which a plurality of nozzles are attached with a predetermined interval is used. This is preferable because it enables reduction of member cost and installation cost. On the other hand, a sand collecting valve for starting/stopping water supply from one water supply pump and adjusting the water supply amount is provided according to the nozzle headers being installed one by one in each area. The sand collecting valve is directly connected to a flow rate adjusting valve for equalizing the injection amount from the nozzle of each nozzle header and a switching valve including an automatic valve for passing water to the nozzle header and stopping water. Further, a similar sand collecting valve is provided for a nozzle provided at the upper end of the main trough for flowing the sand collected in the main trough into the sand collecting pit.

Since the flow rate control valve controls the amount of water required for one area or the water required for the main trough (as an example, 2.0 m ³ /min), it becomes considerably large, so it is not a manual valve but a manual valve. It is necessary to manually adjust the flow rate using a predetermined tool. Therefore, the sand collecting valve is installed above the ceiling wall that covers the upper surface of the sand basin.Because reinforcing materials such as beams are arranged at regular intervals on the ceiling wall, it has traditionally been difficult to operate as a water pump. The pipes connecting the nozzles of the main troughs of the two sand basins and the nozzle headers of the entire area are pierced through the holes formed between the reinforcements in the ceiling wall, and the pipes are located above the ceiling wall. The number of sand collecting valves corresponding to the number of nozzles and each nozzle header was attached.

Japanese Patent No. 3315489

Therefore, conventionally, since holes corresponding to the respective pipelines are provided in the ceiling wall, much work and cost are required for the drilling work and the piping work. Further, since the sand collecting valves attached to the respective pipes are separated, there is a problem that it takes a lot of time for the water passing/stopping work and the flow rate adjusting work of all the sand collecting valves.

An object of the present invention is to provide a sand collecting device that does not require much labor and cost for drilling a ceiling wall and plumbing, and facilitates water passage/stopping work of a sand collecting valve and flow rate adjusting work. And

The present invention, in order to achieve the above object, in a sand collector of a low-pressure sand collecting system in which low pressure water is sprayed from the nozzles of a plurality of nozzle headers on the bottom surface of a sand basin in a drained state to collect sand, the nozzle header Is installed in the area where the bottom of the sand basin is divided into multiple parts at right angles to the water flow direction in the sand basin, near the lower part of the side wall of the sand basin and parallel to the water flow direction in the sand basin. One end of the pipeline for supplying low pressure water is connected, and each pipeline penetrates through the hole formed on the side wall on one side of the sand basin in the ceiling wall that covers the upper surface of the sand basin and above the ceiling wall. is extended to its current sand valve mounting et al are each conduit is extended, the ceiling walls of the holes are a plurality formed at the grit pond water flow direction, the conduit has an upstream side and a downstream side of the grit chamber It is characterized by being divided into and penetrating each hole .

In another embodiment, the low pressure sand collecting apparatus according to the present invention is such that the hole in the ceiling wall is an elongated hole, and a plurality of the conduits are converged and penetrated through the hole. It is a feature.

According to the present invention, it is possible to provide a sand collecting apparatus that does not require much labor and cost for a ceiling wall drilling work and a piping work, and can easily perform a water passage/water stop work of a sand collection valve and a flow rate adjustment work. You can

It is an outline longitudinal section of rainwater treatment equipment concerning an embodiment of the invention. It is a top view which removes the ceiling wall and shows the sand basin of FIG. It is the X1-X1 sectional view taken on the line of FIG. It is the X2-X2 sectional view taken on the line of FIG. It is the X3-X3 sectional view taken on the line of FIG. It is a conceptual diagram which shows the example which divided the bottom face of the sand basin into several areas. It is a development view of a nozzle. It is a figure which shows the water supply system of the sand basin of FIG. FIG. 6 is an enlarged front view of a part of the sand collecting valve group of FIG. 5. It is the X4-X4 sectional view taken on the line of FIG.

Next, an embodiment in which the present invention is applied to a rainwater treatment facility at a pumping station of a terminal treatment plant will be described with reference to the drawings.

As shown in FIG. 1, the rainwater treatment facility 100 has a sand basin 101 and a pump well 102. A sand basin 101 is connected to a downstream side of an inflow conduit (not shown) on the left side of FIG. 1 via a gate (dam device) 104, and a pump well 102 is connected to a downstream side of the sand basin. The gate 104 is installed on the upstream side of the sand basin 101 and allows or blocks the inflow of rainwater into the sand basin. The pump well 102 is equipped with a drainage pump 103A.

A sand collecting pit 105 is formed at the deepest position in the center of the bottom 101a of the sand basin 101, and the bottom of the sand basin 101 is inclined so that the sand collecting pit 105 side becomes deeper from the lower end of the side wall W1 defining the sand basin 101. Is formed in the center of the bottom of the sand basin 101 in the width direction (direction perpendicular to the water flow direction) from the upstream end of the sand basin 101 to the sand collecting pit 105 and the downstream end of the sand basin 101. A main trough 106 is formed so that the sand collecting pit 105 side is inclined deeper from each part to the sand collecting pit 105. In addition, slopes (hereinafter referred to as lateral troughs) 107 are formed so as to descend from the side walls W1 on both sides to the sand collecting pit 105.

The bottom surface 101b of the sand basin 101 is divided into four regions by the main trough 106 and the horizontal trough 107. On the surface of the bottom of each region, a large number of small troughs 108 extending in parallel from the side wall W1 side toward the main trough 106 at equal intervals are formed.

In the illustrated embodiment, each region of the bottom surface 101b is further divided into two regions each, and as shown in FIGS. 6 and 8, has a total of eight regions B1 to B8. .. The number of regions can be arbitrarily set according to the capacities of the water supply pump 103B and the sand pump 103C described later.

As shown in FIGS. 2 and 5, nozzle headers H1 to H8 are installed in the vicinity of the side wall W1 above the areas B1 to B8 of the bottom surface 101b of the sand basin 101. Each of the nozzle headers H1 to H8 has the same structure, and a plurality of nozzles 110 are attached to a mother pipe 109b having a branch pipe 109a at equal intervals.
Each of the nozzle headers H1 to H8 has a plurality of small troughs formed on the bottom of the sand basin from the lower end of the side wall of the sand basin to the main trough 108 in a direction perpendicular to the water flow direction in the sand basin and separated from each other in the water flow direction. One having a length longer than the distance between 108 is used. Further, the nozzle header is formed by connecting both ends of a branch pipe 109a supplied with pressurized water from a water supply pump to a mother pipe 109b in which a plurality of nozzles 110 are provided at equal intervals. Both ends of the branch pipe 109a are connected to the mother pipe 109b at two positions equidistantly spaced from the both ends of the mother pipe 109b to the center side thereof, and each end of the mother pipe 109b is connected to each of the connecting positions of the mother pipe 109b. The number of nozzles 110 provided in the above parts is the same. The number of nozzles 110 provided in the portion of the mother tube 109b between the two connecting positions is 3 times the number of nozzles 110 provided in the portion from each connecting position of the mother tube to each end of the mother tube. Double. (See Figure 5)

The nozzles 110 are of the same type and shape, and as shown in FIG. 7, their injection ports 110a are elliptical with a predetermined size so that water is evenly sprayed on the bottom surface between the small troughs 108. Has been formed. In addition, each of the nozzles 110 has a bottom surface between the small troughs 108 so that the water sprayed from each nozzle 110 collides with the water from the adjacent nozzles and interferes with each other, so that the cleaning function of the bottom is not impaired. Are arranged at a predetermined interval immediately above. Therefore, the sediment on the bottom surface of the sand basin smoothly flows into the small trough 108, and the sand collecting efficiency is improved.

To each nozzle header H1 to H8, one end of a pipe P1 to P8 for connecting the nozzle header H1 to H8 to a water supply pump 103B installed in the pump well 102 is connected, and the pipes P1 to P8 pass through the vicinity of the side wall W1. Between the adjacent reinforcing members 111 of the ceiling wall W2 covering the upper surface of the sand basin 101, the pipes P1 to P8 gathered immediately before the elongated holes 112 formed in the ceiling wall W2 are aligned in the state described above. The pipe P1 extends through the hole 112 to a position above the ceiling wall W2, and the other ends of the pipes P1 to P8 are connected to a water supply pipe P13 connected to the water supply pump 103B. Then, the sand collecting valves V1 to V8 are attached at the same height to the pipes P1 to P8 which are extended and aligned above the ceiling wall W2. The water supply pump 103B corresponds to a fluid supply source, and the pipes P1 to P8 correspond to pipe lines. The nozzle headers H1 to H8 correspond to a plurality of fluid supply destinations. The sand collecting valves V1 to V8 are attached to the aligned portions of the pipelines.

As shown in FIG. 5, the nozzle headers H2 and H4 of the areas B2 and B4 and the sand collecting valves V1, V2, V3 and V4 corresponding to the nozzle headers H1 and H3 of the areas B1 and B3 of FIG. The sand collecting valve group VG1 of No. 1 is composed of the sand collecting valves V5, V6, V7 and V8 corresponding to the nozzle headers H6 and H8 of the areas B6 and B8 and the nozzle headers H5 and H7 of the areas B5 and B7 of FIG. The formed second sand collection valve group VG2 is divided into an inflow side and an outflow side of the sand basin 101, and is provided above the ceiling wall W2 of the sand basin 101. Further, as shown in FIG. 8, since the first and second sand collecting valve groups VG1 and VG2 are gathered on the left side from the inflow side to the outflow side of the sand basin 101, particularly the flow rate adjusting valve It is possible to improve workability when manually performing the above.

All sand collecting valves V1 to V8 have the same configuration. That is, a flow rate adjusting valve Va for adjusting the flow rate of the pressure water from the water supply pump 103B to each of the nozzle headers H1 to H8, and a switching valve Vb for passing water to/stopping each of the nozzle headers H1 to H8. It is configured by directly connecting. Since the flow rate adjusting valve Va has a large flow rate, a manual valve for manually adjusting the flow rate, for example, a ball valve is used. Each of the flow rate adjusting valves Va and the switching valves Vb has a rotation axis of a rotated member (for example, stems S1 and S2 in the case of a ball valve) for applying a rotational force to the valve body by a flow rate adjusting tool such as a wrench. As shown in FIGS. 9 and 10, the pipes P1 to P8 are attached at a predetermined angle (θ2) with respect to the alignment direction L.

The angle θ2 to be inclined with respect to the alignment direction L of the pipes is set to an angle at which the flow rate adjusting work of one flow rate adjusting valve Va and the repair work of the switching valve Vb are not obstructed by the adjacent flow rate adjusting valve Va or the switching valve Vb. It Although there is some variation depending on the type of the flow rate adjusting valve Va, in the case of a general-purpose manual valve, the number of bolt through holes provided in the fixing flange is 8, so the inclination angle is 45 degrees.

In this way, when each flow rate adjusting valve Va is attached at a predetermined angle with respect to the alignment direction L of the conduits P1 to P8, the flow rate adjusting tool T, for example, a wrench or the like, is attached as shown by the alternate long and short dash line in FIG. When performing the flow rate adjusting work by fitting or engaging with the rotated member (S1) and rotating the member, the adjacent flow rate adjusting valve Va or the switching valve Vb does not interfere with the flow rate adjusting work. The effect is obtained. Also when the repair work of the switching valve Vb is performed, the repair work is not disturbed by the adjacent flow rate adjusting valve Va or the switching valve Vb.

Therefore, the installation intervals of the pipes P1 to P8 can be made narrower than in the past, and the length of the long holes provided in the ceiling wall W2 can be shortened accordingly, so that the distance between the reinforcing members 111 should be taken into consideration. Instead, the pipes P1 to P8 can be installed. In addition, the number of processed ceiling walls can be reduced.

Nozzles 110a and 110b are provided also at the highest position of the main trough 106, that is, at the upstream end and the downstream end of the main trough, and the pipes P9 and P10 having one end connected to each nozzle are Below the hole 112 in the ceiling wall W2, the nozzle headers H1 to H4 and H5 to H8 are assembled with the pipes P1 to P4 and P5 to P8, respectively, and are similarly penetrated above the hole 112 and collected in the pipes P9 and P10. The sand valves V9 and V10 are attached in the same manner as the other sand collecting valves V1 to V4 and V5 to V8, and are arranged in parallel in the first and second sand collecting valve groups VG1 and VG2, respectively.

Nozzles 110c are also provided at both ends of the horizontal trough 107, and a pipe P11 having one end connected to the nozzle is assembled with the pipes P5 to P8, P10 below the hole 112 of the ceiling wall W2, and similarly the holes are formed. The sand collecting valve V11 is penetrated above 112, and is attached to the pipe P11 at a predetermined angle (θ2) with respect to the alignment direction of the pipes like the other sand collecting valves V5 to V8 and V10. It is installed in parallel with the sand collection valve group VG2.

Reference numeral 110d in FIGS. 5 and 8 denotes a nozzle for agitating and fluidizing the sand in the sand collecting pit 105. As in the case of other nozzles, the pipe P12 having one end connected to it has a hole in the ceiling wall W2. A sand collecting valve V12 is attached to the pipe P12 at an angle of a predetermined angle (θ2) with respect to the pipe aligning direction L and is arranged in parallel with the second sand collecting valve group VG2. There is.

The pipe P11 of the nozzle 110c of the horizontal trough 107 and the pipe P12 of the sand collecting pit stirring nozzle 110d may be arranged in parallel in either the first group VG1 or the second group VG2.

Regarding the sand collecting valve of each nozzle header, during the test operation, the switching valve Vb is sequentially driven to the water passage side, and the member to be rotated of the flow rate adjusting valve Va is rotated by the flow rate adjusting tool so that The flow rate is adjusted so that the amount of water sprayed in each region is even. Such flow rate adjustment can be performed even after operation by monitoring the injection state of the nozzles of each nozzle header and when necessary.

An automatic screen 113 for removing impurities is provided immediately upstream of the sand basin 101, and the automatic screen 113 captures, for example, levitated matter, underwater suspended matter, and debris such as pebbles and gravel. And is automatically removed by a conveyor or the like. A filter 114 is provided at the downstream end of the sand basin 101 as shown in FIG.

Reference numeral 103B in FIGS. 1 and 8 denotes a water supply pump provided in the pump well 102. In this embodiment, by operating the water supply pump 103B, the water in the pump well 102 is stored in the sand collecting device. Supply to the nozzle headers H1 to H8.

As shown in FIG. 8, the water supply pump 103B is provided with a relief circuit P14, and the switching valve 116 attached to the relief circuit P14 is opened to transfer the water from the water supply pump 103B to the sand basin 101. You can

Water from the water supply pump 103B is supplied to the sand collecting valve groups VG1 and VG2 through the water supply pipe P13, and the sand collecting valves V1 to V12 are driven in a predetermined order by the control of a microcomputer (not shown). Water is sequentially supplied to the predetermined nozzle headers H1 to H8, and is also supplied to the nozzles 110a, 110b and 110c and the stirring nozzle 110d of each trough, and the sand collecting operation in the sand basin 101 is performed.

The sand pump 103C is operated so that the water level of the water accumulated in the sand basin is maintained in the sand collecting pit 105, and the water level in the sand collecting pit is higher than a predetermined high water level. At that time, the operation is automatically started, and when the water level in the sand collecting pit becomes lower than a predetermined low water level, the operation is automatically stopped.

The sand collecting operation by the above configuration is the same as that described in the above-mentioned Patent Document 1, and since it is not directly related to the main part of the present invention, it will not be described in detail here.

As described above, the pipes P1 to P12 are gathered under the holes 112 formed in the ceiling wall W2 that covers the upper surface of the sand basin, and are penetrated through the holes 112 in an aligned state from the gathered position. .. extending to above the ceiling wall W2, and sand collecting valves V1 to V12 are attached to the upper ends of the straight pipe portions SP,. The straight pipe portions SP,... Have connecting pipes CP,.., which are separable by well-known coupling means such as a flange and bolts and nuts on the lower side and the upper side of the hole 112, respectively. All of these connecting pipes CP,... Have the same length and thickness. Therefore, the labor and cost of piping work can be reduced, and the connecting pipe CP can be easily attached/replaced, so that the straight pipe portion SP can be easily increased/decreased or exchanged.

100 Rainwater treatment facility 101 Sand set 102 Pump well 103B Water supply pump P1 to P8 Pipeline H1 to H8 Nozzle header 110, 110a to 110d Nozzle VG1, VG2 Sand collecting valve group V1 to V8 Sand collecting valve Va Flow control valve Vb Switching valve W1 Side wall of sand basin W2 Ceiling wall of sand basin 112 Long hole in ceiling wall SP Straight pipe part CP Connecting pipe

Claims (2)

In a low pressure sand collecting type sand collecting device that collects sand by injecting low pressure water from the nozzles of a plurality of nozzle headers on the bottom of a sand basin in a drainage state,
The nozzle header is provided in a region in which the bottom surface of the sand basin is divided into a plurality of directions at right angles to the water flow direction in the sand basin, is provided in the vicinity of the lower portion of the side wall of the sand basin parallel to the water flow direction in the sand basin,
One end of a pipeline for supplying low pressure water from a water supply pump is connected to each nozzle header,
Each of the pipelines extends through the hole formed in the side wall side of the sand basin on the ceiling wall that covers the upper surface of the sand basin to the upper side of the ceiling wall,
Collecting sand valve mounting et al is in each conduit being its extension,
A plurality of holes in the ceiling wall are formed in the sand basin in the direction of water flow,
The pipeline is divided into an upstream side and a downstream side of the sand basin and is penetrated into each of the holes,
A low-pressure sand-collecting method sand collecting device. The low-pressure sand collecting apparatus according to claim 1,
The hole in the ceiling wall is an elongated hole,
A plurality of the conduits are converged and penetrated into the hole,
A low-pressure sand-collecting method sand collecting device.

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