JP3955403B2 - Shimizu reduction tower and discharge facility using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fresh water reducing tower that mixes fresh water with water taken from the surface of a water intake tower, and a discharge facility using the same.
[0002]
[Prior art]
Conventionally, in a dam selective intake facility, water at an arbitrary altitude can be discharged such that water on the surface of a dam lake is taken and discharged at all times, and muddy water is discharged in the event of a flood. However, if the discharge of muddy water continues for a long time even after the flood, the environment on the downstream side of the dam is contaminated.
[0003]
In order to solve this problem, build a secondary dam in the river upstream of the dam lake, guide the fresh water taken from the secondary dam to the intake tower with a water conduit, and mix it with muddy water to reduce the turbidity of the discharged water. Attempts have been made.
[0004]
[Problems to be solved by the invention]
However, in the method of connecting the sub dam and the intake tower with a water conduit and introducing fresh water directly from the top of the intake tower, when the water level in the intake tower drops, the fresh water falls from the top of the intake tower at high speed. This may damage the gate and the like provided in the intake tower.
[0005]
On the other hand, in a method in which fresh water is mixed with muddy water by, for example, passing a water pipe to the bottom of a dam lake and joining a discharge pipe provided at the lower part of the intake tower, a flow control valve for adjusting the supply amount of fresh water is provided. It must be placed at the bottom of the dam, and a space for installing the flow control valve in the dam must be secured. Moreover, even if it can be installed, there is a problem that its maintenance is difficult.
[0006]
The present invention has been made in consideration of the above problems in the conventional effluent water purification method, and clean water can be safely introduced into the intake tower and mixed with muddy water without being affected by the water level in the intake tower. It is intended to provide a fresh water reduction tower and a discharge facility using the same.
[0007]
[Means for Solving the Problems]
The fresh water reducing tower of the present invention is a fresh water reducing tower that mixes fresh water from the outside with water taken from the surface by the intake tower, and the fresh water reducing tower introduces fresh water from the outside to the upper part of the tower. It has a fresh water introduction path, and a fresh water lead-out path for sending the introduced fresh water to the lower part of the water tower at the bottom of the tower, and the fresh water introduced from the fresh water introduction path in the tower using the height difference The gist of the present invention is to form a depressurizing means for deenergizing while leading to the above.
[0008]
In the present invention in which the fresh water reducing tower is constituted by a cylindrical body, the reducing means can be constituted by a spiral staircase fixed in a spiral manner on the inner wall of the tower. Further, the deenergizing means can be constituted by a folded staircase fixed to the inner wall of the tower. Furthermore, the de-energizing means can be composed of plates protruding in a staggered arrangement on the opposing tower inner walls.
[0009]
The discharge facility of the present invention includes a fresh water reducing tower having any one of the above structures, a weir provided upstream of the river for taking fresh water, a communication passage communicating the fresh water reducing tower and the intake portion of the weir. And a fresh water supply amount adjusting means for adjusting the supply amount of fresh water introduced to the fresh water reduction tower, provided near the fresh water reduction tower in the communication passage.
[0010]
In the above-mentioned discharge facility, the fresh water supply amount adjusting means can be constituted by a water tank for storing fresh water taken from the intake portion of the weir and an adjustment gate for adjusting the discharge amount of the fresh water stored in the water tank. .
[0011]
According to the fresh water reducing tower of the present invention, when fresh water is introduced from the upper part of the fresh water reducing tower, the introduced fresh water flows through the tower toward the fresh water outlet using the height difference of the tower, After the momentum is attenuated by the de-energizing means, it is sent into the intake tower from the fresh water lead-out path. Thereby, clean water can be safely introduced into the water intake tower without being affected by the water level in the water intake tower, and can be mixed with muddy water stored therein.
[0012]
According to the discharge facility of the present invention, the fresh water sent through the long-distance communication passage from the weir provided upstream of the river is temporarily stored in the water tank of the fresh water supply amount adjustment means. There is no need to consider it, so the degree of freedom in designing the communication path can be increased.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.
[0014]
FIG. 1 shows the configuration of a discharge facility to which the fresh water decontamination tower according to the present invention is applied.
[0015]
In the figure, a dam body 2 of a dam lake 1 is provided with a water intake tower 3 for taking surface water from the lake water, and a cylindrical fresh water reducing tower 4 is erected in parallel with the water intake tower 3. Has been. The intake tower 3 always takes and discharges the surface water of the dam lake 1 and discharges muddy water at the time of flooding.
[0016]
An upstream intake weir 6 is provided upstream of the river 5 flowing into the dam lake 1, and fresh water taken from the upstream intake weir 6 is introduced into the fresh water reducing tower 4 through the communication path 7. It has become. In addition, a relay water tank 8 is provided in the communication path 7, and a water control valve 9 is provided in the communication path 7 a between the relay water tank 8 and the fresh water reducing tower 4.
[0017]
Next, the structure of the fresh water reducing tower 4 will be described in detail with reference to FIG. FIG. 2 (a) shows a front view of the fresh water reducing tower 4, and FIG. 2 (b) shows a side view thereof.
[0018]
In FIG. 2, the fresh water reducing tower 4 is configured to reduce the turbidity by mixing fresh water taken from the upstream intake weir 6 with the muddy water when, for example, water is taken from the dam lake 1 after the flood. Yes.
[0019]
The fresh water reducing tower 4 is composed of a steel cylinder tower installed in the vicinity of the intake tower 3, and an end of the communication passage 7 a is connected to the upper part of the tower to form a fresh water introduction path 10. . On the other hand, the lower part of the tower is provided with a fresh water lead-out path 11 for sending fresh water introduced into the fresh water reducing tower 4 to the water storage part 3a at the lower part of the water tower 3.
[0020]
In the fresh water reducing tower 4, a column 12 is provided in the column axis direction of the tower (in the present embodiment, in the vertical direction), and a spiral staircase 13 for reducing pressure is provided spirally with the column 12 as a central axis. It has been. The struts 12 and the spiraling spiral staircase 13 can be regarded as a biasing means. Further, the outer peripheral side of the decelerating spiral staircase 13 is fixed to the inner wall of the tower, and each step of the decelerating spiral staircase 13 is performed so that the fresh water surely flows on the decelerating spiral staircase 13 and descends spirally. Are connected by vertical plates.
[0021]
A manhole 4a is provided at the top of the fresh water reducing tower 4. When the fresh water reducing tower 4 is inspected, the operator can open the manhole 4a and get down onto the reducing spiral staircase 13. It is like that.
[0022]
In addition, an upper portion of the fresh water reducing tower 4 is provided with a supply / exhaust pipe 4b configured as a downward elbow. The air supply / exhaust pipe 4b is for communicating the inside of the fresh water reducing tower 4 with the atmosphere. In order to exhaust immediately after the water introduction, the air is taken along by the water flow and the inside of the fresh water reducing tower 4 is decompressed. In the case of an air supply, the air is supplied into the tower.
[0023]
In the intake tower 3, multistage movable gates 3a, 3b, 3c are arranged, and the screen 3e from the surface of the lake water according to the fluctuating water level of the dam lake 1, specifically, the highest water level WL1 to the lowest water level WL2. The water is taken in through. And the muddy water which overflowed the said gate and was taken in in the intake tower 3 is stored by the water storage part 3a.
[0024]
On the other hand, the fresh water introduced from the upper part of the fresh water reducing tower 4 has potential energy and tries to descend from the fresh water introduction path 10 toward the fresh water lead-out path 11. Since a number of staircase shapes act as resistance to the flow when flowing through the water, the momentum of the flow of fresh water is attenuated, and the reduced fresh water reaches the fresh water outlet pipe 11.
[0025]
The fresh water reduced in this way is supplied into the intake tower 3 via the fresh water outlet pipe 11 and mixed with the muddy water stored in the storage part 3a. The discharged water whose turbidity has been reduced by mixing fresh water is discharged from the discharge pipe 14. In the figure, reference numeral 15 denotes a dam housing, and 15a denotes a dam shaft.
[0026]
FIG. 3 is an AA arrow view of FIG. 1, and shows the arrangement of the fresh water reducing tower 4 and the intake tower 3.
[0027]
In the figure, the fresh water introduced from the fresh water introduction pipe 7 is introduced into the upper part of the fresh water reducing tower 4 which is separated from the dam shaft 15 a by a predetermined distance via the water control valve 9. The water control valve 9 is for closing the fresh water introduction pipe 7 when the maintenance inspection of the fresh water reducing tower 4 is performed.
[0028]
In the fresh water reducing tower 4, fresh water flows in a spiral shape and falls along the peripheral wall of the tower and the spiraling staircase 13 attached to the peripheral wall.
[0029]
FIG. 4 is a view taken along the line B-B in FIG. 1, and shows the arrangement of the fresh water outlet pipe 11 of the fresh water reducing tower 4 and the water storage section 3 a of the intake tower 3.
[0030]
In the figure, a fresh water outlet pipe 11 provided at the lower part of the fresh water reducing tower 4 constitutes an elbow and communicates with a water storage part 3 a formed at the lower part of the intake tower 3. Is supported by a support member 16 attached to the outer wall of the intake tower 3.
[0031]
FIG. 5 shows another embodiment of the fresh water reducing tower according to the present invention. A fresh water reducing tower 10 shown in the figure is made of a concrete cylinder, and a returning stairs 11 for reducing energy is formed therein. In this configuration, the fresh water introduced from the duct-shaped fresh water passage 12 serving as the fresh water introduction path descends into a zigzag while flowing along the de-energizing return stairs 11, and flows over the de-energizing return stairs 11. Since many staircase shapes act as resistance to flow, the momentum of fresh water is attenuated. The reduced fresh water reaches a fresh water outlet (not shown) provided at the lower part of the fresh water reducing tower 10 and is sent out to the intake tower 3.
[0032]
FIG. 6 shows still another embodiment of the fresh water reducing tower according to the present invention. The fresh water reducing tower 20 shown in the figure is made of a concrete cylinder, and a large number of reducing plates 21, 22, 23, 24. Weirs 21a, 22a, 23a, 24a,... Bent upwardly are formed at the tips of the respective force reducing plates.
[0033]
In this configuration, the fresh water introduced from the duct-shaped fresh water passage 30 serving as the fresh water introduction path overflows the weir 21a of the uppermost derating plate 21 and falls onto the next depressing plate 22, and the weir After overflowing 22a, it falls onto the next-stage depressing plate 23, and descends while repeating this operation. Since a large number of depressing plates act as resistance, the momentum of the descending fresh water is attenuated, and the depressurized fresh water reaches a fresh water lead-out path (not shown) provided at the lower portion of the fresh water reducing tower 20, It is sent to the intake tower 3.
[0034]
In the discharge facility of the present invention, it is preferable to provide the relay water tank 8 near the fresh water depressing tower 4 in the communication path 7. That is, the distance from the upstream intake weir 6 to the dam body 2 may reach several kilometers, and if the communication passage 7 is not provided with any flow rate adjusting means, the flow velocity in the pipe changes depending on the shape and gradient of the communication passage 7. As a result, there arises a problem that it becomes difficult to design the pipe line up to the Shimizu de-energization tower 4.
[0035]
Therefore, in this embodiment, the relay water tank 8 is provided in the middle of the communication path 7 so as to adjust the pressure of fresh water taken from the upstream intake weir 6.
[0036]
7A and 7B are a plan view and a front view showing the configuration of the relay water tank 8, respectively.
[0037]
The relay water tank 8 is made of a concrete box or the like, and a height difference is provided between the communication path 7 upstream from the relay water tank 8 and the communication path 7 a downstream from the relay water tank 8.
[0038]
The wall 8a to which the downstream communication path 7a is connected is provided with an adjustment gate 40 that moves up and down, so that the amount of fresh water stored in the relay water tank 8 can be adjusted. Further, a water intake pipe 41 is provided on the side wall 8b of the relay water tank 8 so that water can be taken in as necessary. In addition, 8c is an upper cover.
[0039]
If the relay water tank 8 having the above-described configuration is provided in the middle of the communication passage 7 and the fresh water whose flow rate is adjusted is introduced into the fresh water depressing tower 4, the long distance communication from the weir provided upstream of the river is possible. Since the fresh water sent through the passage 7 is once stored in the water tank, it is not necessary to consider the pressure fluctuation of the communication passage 7, and therefore the degree of freedom in designing the communication passage 7 can be increased.
[0040]
Further, since the upstream intake weir 6 is usually provided in a steep place considerably upstream of the river, even if the upstream intake weir 6 is provided with a flow rate adjusting means, daily management becomes extremely difficult. On the other hand, if the relay water tank 8 is provided in the communication path 7 near the fresh water reducing tower 4, daily management becomes extremely easy.
[0041]
In the above-described embodiment, the fresh water reduction tower is separately installed in parallel with the water tower so that it can be applied to an existing dam. It is also possible to incorporate a fresh water derating tower having a configuration in advance.
[0042]
Further, in the present invention, the deenergizing means is constituted by a spiral staircase, a turn-up staircase, etc. for convenience in maintenance in the above embodiment, but is not limited thereto, and fresh water is directly dropped from the upper part of the water tower. As long as it can be de-energized without any restriction, the de-energizing means having any shape can be used.
[0043]
【The invention's effect】
As is clear from the above description, according to the fresh water reducing tower of the present invention, the fresh water attenuated by the reducing means is introduced into the intake tower, so that it is not affected by the water level in the intake tower. Fresh water can be introduced into the intake tower in a safe state and mixed with, for example, muddy water stored therein.
[0044]
According to the discharge facility of the present invention, the fresh water sent through the long-distance communication passage from the weir provided upstream of the river is temporarily stored in the water tank of the fresh water supply amount adjusting means. Therefore, there is an advantage that the degree of freedom of design of the pipe is increased when the communication path is provided at a long distance from the upstream side of the river.
[Brief description of the drawings]
FIG. 1 is a plan view showing a discharge facility to which a fresh water reducing tower of the present invention is applied.
FIGS. 2A and 2B are explanatory views showing a configuration of a fresh water reducing tower according to the present invention, in which FIG. 2A is a front view and FIG. 2B is a side view;
FIG. 3 is a view taken along arrow AA in FIG. 2;
4 is a BB arrow view of FIG. 2;
FIG. 5 is a perspective view showing a main part of another embodiment of the fresh water reducing tower according to the present invention.
FIG. 6 is a perspective view showing a main part of still another embodiment of a fresh water reducing tower according to the present invention.
7A and 7B are explanatory views showing a configuration of a relay water tank in the discharge facility of the present invention, wherein FIG. 7A is a plan view and FIG. 7B is a front view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Dam lake 2 Dam main body 3 Intake tower 4 Fresh water reduction tower 5 River 6 Upstream intake weir 7 Communication path 8 Relay tank 9 Water control valve 10 Fresh water introduction path 11 Fresh water outlet path 13 Reduction spiral helix 14 Drain pipe

Claims (6)

A fresh water reduction tower that mixes fresh water from the outside with water taken from the surface by the intake tower,
The fresh water reducing tower has a fresh water introduction path for introducing fresh water from the outside to the upper part of the tower, and a fresh water outlet path for sending the introduced fresh water to the lower part of the intake tower at the lower part of the tower. A fresh water depressing tower, comprising: a depressurizing unit configured to depressurize the fresh water introduced from the fresh water introduction path while guiding the fresh water to the fresh water lead-out path using a height difference. The fresh water reducing tower according to claim 1, wherein the fresh water reducing tower comprises a cylindrical body, and the reducing means comprises a spiral staircase fixed to the inner wall of the tower in a spiral shape. 2. The fresh water reducing tower according to claim 1, wherein the fresh water reducing tower is formed of a cylindrical body, and the reducing means is constituted by a folded staircase fixed to the inner wall of the tower. 2. The fresh water reducing tower according to claim 1, wherein the fresh water reducing tower is formed of a cylindrical body, and the reducing means is constituted by a plate protruding in a staggered arrangement on the opposing inner wall of the tower. A fresh water reducing tower according to any one of claims 1 to 4, a weir provided upstream of a river for taking fresh water, a communication passage communicating the fresh water reducing tower and a water intake of the weir, Discharge equipment comprising: fresh water supply amount adjusting means for adjusting the supply amount of fresh water to be introduced into the fresh water reduction tower, provided near the fresh water reduction tower in the communication passage. The said fresh water supply amount adjustment means is comprised from the water tank which stores the fresh water taken from the water intake part of the said weir, and the adjustment gate which adjusts the discharge amount of the fresh water stored in the water tank. Discharge equipment.

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