JP2000212940A - Intake device of river - Google Patents

Abstract

PROBLEM TO BE SOLVED: To basically improve the structure of an intake device so that a maintenance cost of the intake device taking water for drinking, industry, raising or the like from a river can be reduced and, at the same time, that the inflow of foreign matters such as gravel, sand, fallen leaves, wooden pieces, etc., from an intake can be surely prevented. SOLUTION: A water holding channel 11 parallel with a sheathing levee 10 is provided to a wall side on the downstream side of the sheathing levee 10. Then, the upper part of the water holding channel 11 is covered with a filter 12 inclined to the downstream side at a gradient of 5-45 deg. from the upper end of the sheathing levee, a porous air pipe 15 is provided to the inside of the water holding channel 11 along the longitudinal direction of the water holding channel 11, it is connected to a pressure air source through a valve, and an intake pipe 18 is provided to the water holding levee 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water intake device for taking water from a river for drinking, industrial use, aquaculture, and the like, and is capable of preventing foreign matter such as gravel from being mixed into the taken water. It is also possible to reduce the cost of water intake by eliminating the need for maintenance of the water intake.

[0002]

2. Description of the Related Art A conventional water intake device for taking water from a river for drinking water or aquaculture ponds has a structure schematically shown in FIG. 8, and includes a water intake weir 1 having a height of 1 to 1.5 m. A gate valve 3 is provided at an intake port on the upstream side of the intake weir 1, and water taken in from the intake port is guided to a sedimentation basin 2, where the mud, gravel, fallen leaves, wood chips, sand, etc. are collected. It has been removed. However, a large amount of leaf litter is mixed in river water and snowmelt water in the season with lots of leaf litter, and especially in snowmelt water, a large amount of leaf litter that tends to sink is mixed.
These flow in from the intake and flow into the sand basin, where they settle and deposit. In the rainy season and typhoon season, the flow of the river flows violently while involving gravel, sand, and wood chips, so the tendency is even stronger. For this reason, in the conventional water intake device, it is necessary to periodically clean the sand basin, and it is said that the construction cost of the taken-in water treatment device, the treatment cost of the taken-in water, and the maintenance cost of the water intake device increase. There's a problem.

[0003]

SUMMARY OF THE INVENTION The present invention is to reduce the maintenance cost of a water intake device and to prevent foreign substances such as gravel, sand, leaves, and wood chips from flowing from the water intake port without fail. It is an object of the present invention to improve fundamentally.

[0004]

The means taken to solve the above problems are constituted by the following elements (a) to (d). (A) A water receiving groove parallel to the dam is provided on the downstream side wall of the dam, and (b) a filter inclined above the water receiving groove at an inclination of 5 to 45 degrees from the upper end of the dam to the downstream side. (C) disposing a perforated air pipe in the water receiving groove along the longitudinal direction of the water receiving groove, and connecting this to a pressure air source via a valve; Provision of an intake pipe in the groove.

[0005]

[Function] The flow of the river passes over the upper end of the dam, draws a parabola, and flows downstream. However, since the filter is arranged at an inclination of 5 to 45 degrees downstream from the upper end of the dam, This parabolic water flow is caught by this filter and slides over it and flows over the filter. Therefore, a part of the water flow caught by the filter passes over the upper end of the dam and falls into the water receiving groove through the filter. Gravel, litter, sand, etc., which has passed over the dam together with the water flow pass through the filter, so that they do not enter the water receiving groove, and therefore,
It does not settle or accumulate in the water receiving groove. If the slope of the filter is too small, the percentage of water passing through the filter will increase, so the water intake efficiency will be high, but the momentum of the water flowing down the filter will be weak, so gravel, fallen leaves, sand, etc. will stop on the filter and clog. It is easy to cause, and conversely, if the gradient is too large, the flow of water flowing down on the filter is strong,
Although clogging of the filter due to gravel, leaf fall, sand, etc. is reduced, the water intake efficiency is reduced because the proportion of water passing through the filter is small. The width of the water intake device depends on the amount of water in the river, the required amount of water intake, etc.If the amount of water intake per unit area of the filter can be small, increase the slope and increase the filter per unit area. If it is necessary to increase the water intake, the slope should be reduced. However, in view of the problem of filter clogging and the efficiency of water intake per unit area of the filter, a range smaller than 5 degrees and larger than 45 degrees is not practical. The water filtered by the filter and dropped into the water receiving groove is taken into the water intake from the water receiving groove. When the clogging of the filter becomes remarkable and the water intake efficiency decreases, the water level in the water receiving groove decreases, the flow velocity in the water intake pipe decreases, and the water intake flow rate decreases. At this time, after the electric valve closes and the flow of water stops, the electromagnetic valve connected to the perforated air pipe is opened to send pressure air to the perforated air pipe and blow out from the air hole of the perforated air pipe toward the filter. Let it. Since this air blows upward from the lower surface of the filter, the gravel, leaves, sand, and the like that have clogged the filter are blown off and are flushed with the water to clean the filter.
Thereafter, the electromagnetic valve is closed to stop the supply of air, and then the electric valve is opened to start water intake. Therefore, the water intake efficiency is restored. By performing this cleaning at predetermined intervals, a constant water intake efficiency is maintained. If it is inevitable that minute sand or the like will accumulate on the bottom of the water receiving groove for a long time, and if it is necessary to clean the filter, open the drain hole at the bottom of the water receiving groove to open the filter. It is naturally washed away by the water that has fallen off the mesh. Therefore, the cost for cleaning the water receiving groove is almost zero.

[0006]

[Embodiment 1] The high-pressure air source in the solution is constituted by a compressor and an accumulator.

[0007]

[Function] Since the compressed air can be stored in the accumulator, the required high-pressure air amount can be supplied to the air pipe, and the capacity of the compressor can be small, so that the equipment cost can be reduced. .

[0008]

[Embodiment 2] A flow meter and a turbidity meter are provided in an intake pipe in the solution means, and a valve control device responsive to a flow signal from the flow meter and a turbidity signal from the turbidity meter is provided.

[0009]

When the filter is clogged, the flow taken in from the water intake pipe decreases. By detecting the decrease in the water quantity with a flow meter, the timing for cleaning the filter by blowing high-pressure air from the porous air pipe is determined. Can be detected. When the flow rate by the flow meter falls below the reference value, the valve control device is activated by the flow signal, the air valve is opened, high-pressure air is automatically supplied to the perforated air pipe, and the filter is automatically cleaned. Done in In addition, when the river becomes turbid due to rain or snow melting water, the turbidity of the water intake increases, and if the water is taken as it is, a burden is imposed on the water treatment, which is not preferable. Therefore, when the turbidity of the water intake is detected by a turbidity meter and exceeds the reference value, the valve control device is activated by the turbidity signal, the electric valve is closed and the water intake is automatically stopped. As described above, the operation of cleaning the filter is automatically performed when necessary, and the operation cost of the water intake device according to the present invention is low because unnecessarily turbid water does not enter.

[0010]

[Embodiment 3] An air guide for directing jet air toward a filter is provided in a perforated air tube in the solution means.

[0011]

The high-speed air flow blown out from the air hole of the multi-hole air pipe is guided toward the filter by the air guide, so that the efficiency of cleaning the filter by the high-speed air flow is improved.

[0012]

[Embodiment 4] The perforated air pipe in the solution means is arranged at the bottom of the water receiving groove.

[0013]

The perforated air pipe is disposed below the water surface of the water receiving groove by disposing the perforated air pipe at the bottom of the water receiving groove. Therefore, since the water in the water receiving groove is blown toward the filter together with the high-speed air flow by the high-speed air flow blown from the perforated air tube toward the filter,
The filters are cleaned very efficiently.

[0014]

Next, an embodiment will be described with reference to the drawings.
The embodiment shown in FIG. 1 is an example in which a water receiving groove 11 is provided at the upper end of a bank 10 having a river width of 3 m. A water receiving groove 11 is provided by attaching a concrete structure having an L-shaped cross section to a wall surface on the downstream side of a 1.5 m high bank. A small-meshed wire mesh filter 12 is passed between the upper end of the bank 10 and the upper end of the side wall 11a of the water receiving groove 11 to cover the water receiving groove 11.
The inclination of the filter 12 is 20 degrees. Water receiving groove 11
The width of the groove in the flow direction varies depending on the flow rate of water flowing through the upper end of the dam and the amount of water withdrawal.
0 cm is appropriate, and in this embodiment, the inner method is set to 50 cm. Further, the depth of the water receiving groove 11 depends on the connection position (height from the groove bottom) of the intake pipe 18 and the diameter of the pipe, but it is preferable that the intake pipe 18 be 10 to 15 cm below the water surface. . In this embodiment, since the diameter of the water intake pipe 18 is 15 cm, the depth of the groove is set to 25 cm. Filter 12
The supporting structure shown in FIG. 2 is as shown in FIG. 2, in which a grating 13 is passed over the water receiving groove 11, a perforated steel plate 14 is put on the grating 13, and a filter 12 is put on the perforated steel plate 14. The wire mesh forming the filter 12 has a wire diameter of 0.3 mm to 5.0 mm and a gap between the wire wires of 0.3 mm to 3.0 mm. At the bottom of the water receiving groove 11, a perforated air tube 15 having an outer diameter of 8 cm is arranged along the downstream side wall surface of the dam 10, and a number of small holes (air holes) 15a facing the filter 12 are provided in this. is there. Also,
The high-speed airflow blown out from the small hole 15a is
There is provided an air guide 16 for directing toward. This air guide 16 is used to filter a large number of flat
2, the interval and the height thereof depend on the depth of the water receiving groove 11, but the upper end of the flat plate may be located several cm or more below the water surface. .
The high-speed airflow blown out causes the water in the water receiving groove 11 to be caught and blown to the filter. The height of the river bottom upstream of the bank 10 is almost the same as the upper end of the bank 10, and the upper layer of the river bottom is a gravel layer 17. Thereby, the flow of water upstream of the bank 10 is adjusted, the flow at the upper end of the bank becomes laminar, and the turbulence of the water flowing on the filter can be reduced. The intake pipe 18 is provided with a flow meter 20, a solenoid valve or an electric valve 21, and a turbidity meter 19, and the perforated air pipe 15 is provided with a solenoid valve or an electric valve 2.
2, an accumulator (air tank) 23 is provided. This accumulator 23 has a pressure of 3 to 10K.
g / cm ^2, the capacity is ^{1 m} 3 through 10m ^3, connects the small compressor 24 thereto.

Since the flow rate signal from the flow meter 20 is transmitted, when the flow rate becomes lower than the reference value, the solenoid valve or the electric valve 21 of the water intake pipe 18 is closed by the valve controller 25 in response to the flow rate signal. After stopping the flow of water, the solenoid valve or the motor-operated valve 22 of the porous air pipe 15 is opened, and high-pressure air is supplied from the accumulator 23 to the porous air pipe 15. Thereby, many small holes (air holes) 15 are formed.
High-pressure air is blown out from a to the filter 12.
The blowing time of the high-pressure air may be 10 seconds to 45 seconds,
This time is controlled by a timer in the valve control device 25. When a predetermined time is reached, the solenoid valve or the electric valve 22 is automatically closed by the valve control device 25, the blowing of high-pressure air is stopped, and the electromagnetic valve or the electric valve is stopped. The valve 21 is opened to start water intake. Since the blowing time of the high-pressure air can be freely adjusted by adjusting the timer setting, it may be appropriately adjusted according to the actual cleaning condition of the filter 12.

The second embodiment shown in FIG. 6 is suitable for taking a large amount of water from a river having a relatively large amount of water, and a wall 3 is placed on a concrete floor 32 cast downstream of a dam 31.
3, and a wide water receiving groove 34 is constituted by the bank 31, the concrete floor 32, and the wall 33. In this embodiment, the width of the water receiving groove is 100 cm. For this reason, it is difficult to clean the entire surface of the filter with a high-speed airflow blown out from one porous air tube. Therefore, in this embodiment, two porous air tubes 35 are arranged. Two perforated air tubes 35, 35 are connected to one accumulator, and at the same time, two perforated air tubes 35, 35 are connected.
When high pressure air is blown out from the structure, the distribution of high pressure air to both porous air pipes 35 and 35 becomes a problem,
It is necessary to distribute high-pressure air to the two perforated air pipes 35 by a flow distribution valve. In this case, the dam 31
Since the distance of the high-speed airflow blown out from the porous air pipe 35 closer to the air tube reaches the filter 12, the distribution amount of the high-pressure air to the porous air pipe 35 is determined by the water receiving groove 3.
It is necessary to increase the number of perforated air tubes 35 closer to the wall 33 of the fourth. In this way, the two-hole air tubes 35, 35
The speed of the high-speed airflow blown from the filter 12 is made substantially the same on the lower surface of the filter 12. Example 2
Since the amount of high-pressure air used is large, it is necessary to make the capacity of the accumulator 23 suitable. However, when the structure is such that both porous air tubes are selectively connected to the accumulator by a valve, there is no problem of the distribution of high-pressure air as described above. Figure 6 for other points
This embodiment is not different from the embodiment of FIG. As the filter, a filter made of a stainless steel thin plate with many fine holes, a large number of fine slits extending in a direction perpendicular to the flow direction, or a thin wire rod with a fine gap (for example, 0.3 to 3) is used. .0 mm) and are densely arranged in the direction of flow in order to smooth the flow of water on the filter. In addition, dust and foreign matter are less likely to enter when arranged at right angles to the flow. However, from the viewpoint of reducing the construction cost, a commercially available wire mesh having a small mesh is desirable.

[0017]

As described above, the water intake device of the present invention has a lower construction cost than the water intake device of the conventional structure, and the riverbed on the upstream side of the dam rises due to the accumulation of sediment. Since it does not occur, it is possible to exhibit the specified intake capacity over many years, open the weir, lower the water level upstream of the weir, or close the intake valve and clean the sand basin. Therefore, it is not necessary to stop water intake for a long time. Filter clogging can be cleaned automatically using high-pressure air in a short time, and automatically.
The intake efficiency can be kept almost constant throughout the year,
Since the maintenance cost of the water intake device requires little manpower, the cost is remarkably low. In addition, since gravel, sand, and leaf fall hardly enter the taken-in water, a treatment device for the taken-in water can be simplified, and the cost of treating the taken-in water can be reduced. Furthermore, the water intake device is a water receiving groove and a filter attached to the downstream side of the dam, a porous air pipe, an accumulator, and a compressor. The filters, the porous air pipe, the accumulator, and the compressor are relatively inexpensive because they are industrial products. ,
Further, since a sand basin is not required unlike the conventional water intake device, the construction cost is not different from that of the conventional water intake device.

[Brief description of the drawings]

FIG. 1 is a side view of a first embodiment.

FIG. 2 is an enlarged sectional view of the filter of FIG.

FIG. 3 is a front view of the first embodiment.

FIG. 4 is a plan view of the first embodiment.

FIG. 5 is a conceptual diagram of a control system according to the first embodiment.

FIG. 6 is a side view of the second embodiment.

FIG. 7 is a plan view of a second embodiment.

FIG. 8 is a schematic view of a conventional water intake device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Intake weir 2 ... Sand basin 3 ... Gate valve 11, 34 ... Water receiving groove 11a ... Side wall 12 ... Filter 15, 35 ... Perforated air pipe 16 ... Air guide 17 ... Gravel layer 18 ... Intake pipe 19 ... Turbidity meter 20 ... Flow meter 21, 22 ... Solenoid valve or electric valve 23 ... Accumulator 24 ... Compressor 25 ..Valve control device 31 ... bank 32 ... concrete floor 33 ... wall

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[Procedure amendment]

[Submission date] January 22, 1999 (1999.1.2
2)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

[Fig. 1]

FIG. 2

[Fig. 3]

[Fig. 4]

[Fig. 5]

[Fig. 6]

[Fig. 7]

[Fig. 8]

Claims (5)

[Claims] A water receiving groove parallel to the dam is provided on the downstream side wall of the dam, and the upper part of the water receiving groove is inclined from 5 to 45 degrees from the upper end of the dam.
The water receiving groove is covered with a filter inclined to the downstream side, and a porous air pipe is disposed along the longitudinal direction of the water receiving groove in the water receiving groove, and this is connected to a pressure air source via a valve. A water intake device for rivers with an intake pipe in the ditch. 2. The river water intake device according to claim 1, wherein said high-pressure air source comprises a compressor and an accumulator. 3. The river intake according to claim 1, wherein a flow meter and a turbidity meter are provided in the intake pipe, and a valve control device is provided for responding to a flow signal from the flow meter and a turbidity signal from the turbidity meter. apparatus. 4. The river intake device according to claim 1, wherein an air guide for directing the jet air to the filter is provided in the perforated air pipe. 5. The river water intake device according to claim 1, wherein said perforated air pipe is disposed at a bottom of a water receiving groove.