JP2833322B2 - Underground drainage system and its operation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for collecting inflow water such as rainwater that flows into a waterway including a small river into an underground discharge channel provided underground, and guiding the collected inflow water to a drainage pumping station. The underground drainage system discharged to the sea and the like and its operation method are particularly suitable for application to a large-scale underground drainage system planned in urban areas.

[0002]

2. Description of the Related Art As such underground drainage systems, those described in Japanese Patent Application Nos. 3-148557, 3-139165, 3-260412 and 3-330301 have been considered.

[0003]

In the above-mentioned large-scale underground drainage system, inflow from a plurality of rivers or drainage channels to the underground drainage channel occurs at the same time. Japanese Patent Application No. 3-330
When a fixed overflow weir is installed in a headrace that conducts water from a river or drainage to a shaft as described in 301, the amount of water that exceeds the initially determined weir level of each river or drainage is set. It flows into the underground drainage at the same time, and it is impossible to finely control the total inflow and the inflow from each river and drainage channel.In some cases, the pumping capacity installed at the end of the underground drainage channel may be reduced. Excessive inflow may occur and there is a danger of flooding.

[0004] Further, in the above-mentioned system, it is difficult to predict when and how much the initial inflow will occur, it is very difficult to start the pump, and the start-up may cause flooding damage or start-up. If it is too early, the dry operation will be performed for a long time, and the pump may be damaged. That is, it is technically difficult in a large-scale underground drainage system to make the pump idle and run idle before the inflow occurs, and to immediately perform the drainage operation when the inflow occurs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a large-scale underground drainage system that can cause flooding and other flood damage even when a sudden large-scale inflow from each river or drainage to an underground drainage is expected. There is no underground drainage system and its operation method.

Another object of the present invention is to provide a highly reliable underground drainage system which can solve the difficulty of the timing of starting the pump in the initial stage of inflow and can avoid a severe dry operation as a standby operation of the pump, and its operation. Is to get the way.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a large underground spillway inclined at a deep depth underground, and the underground spillway includes various drainage channels near rivers and the ground surface. In the underground drainage system configured to drain the drainage from the vertical shaft, drainage collected in the underground discharge channel from the deep underground pumping station to the surface rivers and the sea, etc., from the river or drainage A movable inflow water amount adjusting device is provided in a headrace channel to a shaft. The movable inflow water amount adjusting device is, for example, a movable weir. When the headrace is a pipe, a valve can be used as a movable inflow water regulator.

[0008] Another feature of the present invention is that an underground spillway is provided under the ground, and drainage flows down the underground spillway from various drainage channels near rivers and the surface of the ground through a shaft. In an underground drainage system configured to drain drainage accumulated in a water channel from an underground pumping station to a river or sea on the surface of the ground, and provided with a movable inflow water amount control device in a headrace channel from the river or drainage channel to a shaft, The operating state of the pump, the water level of the underground discharge channel, the inflow into the underground discharge channel, or their predicted values are obtained, and the inflow water control device is controlled in accordance with this result to control the inflow water control device from the river or drainage to the underground discharge channel. Operating method of underground drainage system to control inflow of wastewater. In particular, for rivers and drains where rapid inflow is expected based on the inflow from the rivers and drains or the prediction results, water is preferentially guided to the underground drains in advance, and the water level of the underground drains is determined. After the water is raised to the lowest water level at which the pump can be operated, the pump is started up, drainage operation is performed before sudden drainage flows into the underground drainage channel, and the pump is put on standby in preparation for sudden inflow. It is valid.

[0009] Another feature of the present invention is that a large underground drainage channel is provided at a deep underground, and drainage from the various drainage channels near the surface of the river is drained down the underground drainage channel through a shaft. An underground drainage system configured to drain the drainage accumulated in the underground water discharge channel from the deep underground pumping station to a river or sea on the surface of the ground, wherein the underground water discharging channel upstream of the underground pumping station is movable. We have a weir.

[0010] Still another feature of the present invention is that an underground spillway is provided under the ground, and drainage flows from the various drains near rivers and the ground through a shaft to the underground spillway. The drainage collected in the spillway is configured to be drained from the deep underground pumping station to a river or sea on the surface of the ground, and a movable weir is provided in the underground spillway on the upstream side of the underground pumping station. It is an object of the present invention to adjust the height of the movable weir in accordance with the inflow from the road or the prediction result thereof, stabilize the water level of the pump well, and stably operate the pump.

[0011]

[Function] A large-capacity water discharge channel with a slope is installed underground. Drainage flows from various drainage channels near rivers and the ground through vertical shafts into this water discharge channel, and drainage collected in the underground water discharge channel In an underground drainage system configured to drain water from the underground pumping station provided in the underground discharge channel to rivers and the sea, the amount of inflow from each river and drainage channel to the underground drainage channel is appropriately distributed by movable weirs and the like. It is possible to prevent flood damage such as flooding, and to perform optimal drainage operation as the entire drainage system.

In the large-scale drainage system, the timing of starting the pump at the initial stage of inflow is determined by controlling the inflow amount from each river or drainage channel because the inflow water amount adjusting device is provided in the headrace channel from each drainage channel or drainage channel. Can be controlled and distributed appropriately.

Further, by using such an inflow water amount adjusting device, when a large amount of rapid inflow is expected from a river or a drainage channel, water is previously guided from the river or the drainage channel to the underground drainage channel, and drainage is performed. By raising the water level to a level at which the pump can be operated, the pump can be operated in a standby mode without dry operation, and the water level in rivers and drains can be lowered. It is possible to perform a drainage operation with a sufficient margin. The reliability of a large-scale underground drainage system can be improved.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the underground drainage system of the present invention, and FIG. 2 shows the configuration of a conventional underground drainage system.

In these figures, 1, 2 and 3 are inflow shafts, 4 is a large-capacity deep underground drainage channel connected to the inflow shaft, 5 is an air hole, 6 is a pump well (a deep underground pumping station), Reference numeral 7 denotes a pump. Drainage that has flowed into the inflow shafts 1, 2 and 3 from the rivers and drainage channels is led to the underground drainage channel 4, and is drained from the pump well 6 provided in a part of the underground drainage channel 4 to the surface rivers and the sea by the pump 7. The underground drainage system is configured as follows. In the present invention, as shown in FIG. 2, an overflow weir or the like is provided in a headrace that guides drainage from a river or a drainage channel to the inflow shafts 1, 2, and 3, and a water level higher than the safety water level of the river or the drainage channel is provided. When it rises, it is drained to the inflow shafts 1, 2, 3 and guided to the underground water discharge channel 4. In such a system, when the system becomes large-scale and controls a plurality of rivers and drainage channels, only the configuration shown in FIG.
The amount of wastewater flowing into 3 is determined by the weir height and water level of the overflow weir, and it is not possible to precisely control the amount of inflow from each river or drainage into the underground drain.

Therefore, in the present invention, as shown in FIG.
A movable inflow adjusting device 8 is provided in a headrace from a river or a drainage channel to the inflow shafts 1, 2, and 3. In this way, the inflow from each river or drain to the underground discharge channel 4 is adjusted, and the inflow from each river or drain to the inflow shafts 1, 2, 3 according to the water level or inflow of each river or drain. The amounts can be adjusted separately.

FIGS. 3 and 4 show the movable inflow amount adjusting device 8 shown in FIG. As the movable weir 9, one that can adjust the height of the weir up and down as shown in FIG. 3 and a swing type as shown in FIG. 4 can be considered, but in a large-scale system, the control power is reduced. FIG. 3 is better because it is possible and hardly catches foreign matter.

FIG. 5 shows an inflow shaft 1 from a river or a drainage channel.
The headraces 2 and 3 are conduits, and the flow control device 8 in FIG. 1 is a valve. In this case, as the valve, a butterfly valve which can adjust a flow rate and can produce a relatively large valve is suitable.

Next, a method of operating the underground drainage system configured as described above will be described. That is, based on the operation state of the pump 7, the water level of the underground water discharge channel 4, the total inflow amount, or the prediction result and the water level of each river or drainage channel, the optimum inflow amount from the river or drainage channel is determined. Adjustment is made to the optimum value by the adjusting device 8. For example, when the inflow into a specific river or drainage is large due to weather conditions and the risk of flooding occurs, as long as the operation state of the pump 7, the water level of the underground drainage channel 4, and the total inflow amount allow, By preferentially draining from the river or drainage channel, flood damage can be prevented, and the maximum capacity of the drainage system can be exhibited.

This will be described with reference to FIG. As shown in the figure, a plurality of rivers A and drains B
And a state in which the sewer C is controlled. Control device 1
2, the water level of the river A, the drainage channel B and the sewer C, the inflow amount Q into the inflow shafts 1, 2, and 3; the water level of the underground drainage channel 4;

If the rainfall in the basin of the river A is large and the water level is rising, the operation state of the pump is grasped from the water level of the underground water discharge channel 4, the drainage amount of the drainage pump 7, and the like.
If there is enough capacity of the pump, a control signal is sent to the flow control device 8 of the river A to increase the inflow Qa from the river A. At this time, even if the capacity of the drainage pump 7 is not enough, if the water level rising speed of the river A is high and there is a possibility of flooding, there is enough room for the water level of the other drainage channel B and the sewer C. In such a case, a control signal is sent to the flow control devices 8 to reduce the inflows Qb and Qc, and thereafter the control devices 1 are controlled to increase the inflows Qa from the river A.
By configuring 2, the function of the drainage system can be maximized and the reliability of the drainage system can be improved.

Also, based on the inflow of rainwater from rivers and drains or the prediction results thereof, rivers and drains that are expected to suddenly inflow are preliminarily preferentially guided to the underground drainage channel 4.
If the water level rises to the lowest operable water level of the pump, then the pump is started and drainage operation is performed, and if the water level of the river or drainage channel is lowered to near the minimum water level, the storage effect of the river or drainage channel itself , The standby operation of the pump can be performed in preparation for a sudden inflow.

At this time, if the pump 7 is constituted by a movable blade pump or a pump whose rotation speed can be controlled and the drainage operation is performed at a low flow rate, the drainage capacity by the natural flow of the river or drainage channel can be used to the maximum. Thus, efficient standby operation can be performed.

FIG. 7 shows another embodiment of the present invention, in which a movable weir 11 is provided in the underground water discharge channel 4 on the upstream side of the pumping station.
Is provided. With this configuration,
It is possible to prevent the initial sewage from flowing into the pump well 6 at the initial stage of the inflow, and the reliability of the pump 7 can be further improved.

When this drainage system is operated in an open channel state, it depends on the gradient θ of the underground drainage channel 4. For example, if the pump 7 is delayed due to a malfunction of the pump 7, etc. Can make full use of the storage effect of the underground water discharge channel 4 by closing the movable weir 11.

Further, with such a configuration, the water level of the pump well 6 can be stabilized by adjusting the height of the movable weir 11 in accordance with the inflow from the river or drainage or the predicted result. Therefore, the operation of the pump 7 can be stabilized, so that the reliability of the pump 7 can be enhanced particularly in the case of a large-scale pump system.

According to the above-described embodiment of the present invention, the amount of inflow from a river or a drainage channel to an underground drainage channel can be adjusted by a movable inflow water amount control device.

Further, the amount of inflow from a plurality of rivers and drainage channels into the inflow shaft can be adjusted, so that an optimal operation as a drainage system can be performed.

Further, the pump can be operated in standby mode by utilizing the storage effect of the river or drainage channel where rapid inflow is expected.

Further, since the water level of the pump well can be stabilized, and the operating state of the pump can be stabilized, the reliability of the system can be improved.

[0032]

According to the present invention, in a large-scale underground drainage system, even if a sudden large-scale inflow from each river or drainage into the underground drainage is expected, flooding and other flood damage will occur. And a method of operating the underground drainage system without any problems.

Further, according to the present invention, a highly reliable underground drainage system capable of solving the difficulty of starting the pump in the initial stage of inflow and avoiding a severe dry operation as a standby operation of the pump, and its operation. You can get the way.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an underground drainage system according to one embodiment of the present invention.

FIG. 2 is a sectional view illustrating a general underground drainage system.

FIG. 3 is a sectional view showing an example of an inflow amount adjusting device used in the present invention.

FIG. 4 is a sectional view showing another example of the inflow rate adjusting device used in the present invention.

FIG. 5 is a sectional view showing another example of the inflow rate adjusting device used in the present invention.

FIG. 6 is a block diagram illustrating an example of a control method when controlling a plurality of rivers in the present invention.

FIG. 7 is a sectional view of an underground drainage system showing another embodiment of the present invention.

[Explanation of symbols]

1,2,3 ... inflow shaft, 4 ... underground drainage channel, 5 ... air vent,
6 pump well, 7 drain pump, 8 inflow rate adjusting device,
9: movable weir, 10: valve, 11: movable weir, 12: controller.

Claims (7)

(57) [Claims] A large underground spillway is provided at a large depth underground. Drainage from various drainage channels near rivers and the ground surface is drained down the underground spillway through a vertical shaft. In an underground drainage system configured to drain the accumulated drainage from the deep underground pumping station to a river or sea on the surface, a movable inflow water regulator is provided in a headrace from the river or drainage channel to a shaft. Underground drainage system characterized by that. 2. The underground drainage system according to claim 1, wherein the movable inflow water amount adjusting device is a movable weir. 3. The method according to claim 1, wherein the headrace is a pipe.
An underground drainage system characterized in that a valve as a movable inflow water amount adjusting device is provided in a part of the pipe. 4. An underground water discharge channel which is inclined under the ground, drains water from various drains near rivers and the surface of the ground through a shaft, and drains water collected in the underground water discharge. In an underground drainage system configured to drain water from underground pumping stations to rivers and seas on the surface of the ground, and provided with a movable inflow water amount adjustment device in the headrace from the river or drainage channel, the operating state of the pump, The water level of the spillway, the amount of inflow to the underground spillway, or a prediction value thereof are obtained, and the inflow amount control device is controlled in accordance with the result to adjust the amount of inflow from the river or drainage to the underground spillway. An operation method of an underground drainage system, characterized in that: 5. The underground drainage channel according to claim 4, wherein, based on the inflow from the river or drainage or a result of the prediction, a river or drainage where rapid inflow is expected is preferentially given to the underground drainage channel in advance. Guide the water, raise the water level of the underground spillway to the lowest operable level of the pump, start the pump, and perform drainage operation before sudden drainage flows into the underground spillway,
A method of operating an underground drainage system, wherein a pump is operated in standby mode in preparation for a sudden inflow. 6. A large-capacity underground drainage channel inclined at a large depth underground is provided, and drainage from the various drainage channels near rivers and the surface is allowed to flow down the underground drainage channel through a shaft. In the underground drainage system configured to drain the accumulated water from the deep underground pumping station to a river or sea on the surface, a movable weir is provided in the underground drainage channel upstream of the underground pumping station. Underground drainage system characterized by the following. 7. An underground sewage channel inclined underground is provided. Drainage flows from various drainage channels near rivers and the surface of the ground through a shaft to drain the sewage collected in the underground waterway. It is configured to drain from the deep underground pumping station to rivers or the sea on the surface, etc., and a movable weir is provided in the underground drainage channel on the upstream side of the underground pumping station, and the amount of inflow from the river or drainage channel or A method of operating an underground drainage system, comprising: adjusting a height of the movable weir in accordance with a prediction result, stabilizing a water level of a pump well, and stably operating a pump.