JPH06262199A - Purifying method and purifying device for tidal canal - Google Patents

Abstract

(57) [Summary] [Purpose] Easily and easily discharge the organic suspension deposited in the tidal canal to the outside without resorting to dredging work. [Structure] The underwater ejector 5 is placed inside the tidal canal where seawater flows in and out as the tide ebbs. The controller 6 determines the ebb tide based on the signal from the tide meter 4.
To intermittently activate the underwater ejector 5 at low tide,
A water stream containing bubbles is jetted toward the bottom of the canal. In this case, the suspended matter that accumulates at the bottom of the canal is floated up and discharged by the tidal current to the outside of the canal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a purifying method and a purifying apparatus for a tidal canal in which seawater flows in and out when the tide is full.

[0002]

2. Description of the Related Art Generally, when an organic suspension in river water or sewage treatment water is deposited on a tidal canal in a city, it forms a sediment. Corrosion gas is generated from the bottom sediment of this tidal canal, and COD
Elution of the components occurs, resulting in a bad odor and a decrease in transparency. For this reason, conventionally, regular dredging has been carried out to remove sediment that has settled at the bottom of the tidal canal. However, when drought is performed, it is generally difficult to set the timing of implementation, and when the drought is performed, bad odor and COD elution increase. In addition, when carrying out dredging, there are problems such as hindrance to the operation of ships and the need to dispose of dredged sludge.

The present invention has been made in consideration of the above points, and provides a tidal canal purification method and a purification apparatus capable of easily discharging the bottom sediment of a canal without performing dredging work. The purpose is to do.

[0004]

The invention according to claim 1 is
The step of arranging an underwater ejector in a tidal canal that has a predetermined tidal velocity with seawater flowing in and out as the tide goes down, and at the time of low tide, the underwater ejector is intermittently activated to generate a water flow containing bubbles. The method for purifying a tidal canal is characterized by comprising the steps of:

According to a second aspect of the present invention, the step of disposing an underwater ejector in a tidal canal having a predetermined tidal velocity with seawater flowing in and out along with the ebb of the tide; From the step of intermittently starting while moving toward the downstream side, and injecting a water flow containing bubbles from the underwater ejector toward the bottom of the canal,
It is a purification method for tidal canals, characterized in that suspended solids that accumulate at the bottom of the canal are floated and discharged outside the canal.

According to the third aspect of the present invention, an underwater ejector is provided in a tidal canal having a predetermined tidal velocity as well as inflow and outflow of seawater as the tide ebbs and ejects a water flow containing bubbles toward the bottom of the canal. A tidal canal purification, characterized by comprising a controller for intermittently activating the underwater ejector when the tidal canal ebbs, and suspending suspended matter accumulated at the bottom of the canal and discharging it to the outside of the canal. It is a device.

According to the fourth aspect of the present invention, seawater flows in and out along with the ebb of the tide and is provided in the tidal canal having a predetermined tidal velocity in order from the upstream side to the downstream side.
A plurality of underwater ejectors that inject a water stream containing bubbles toward the bottom of the canal, and the plurality of underwater ejectors from the upstream side toward the downstream side during the ebb tide of the tidal canal, sequentially at predetermined time intervals. It is a tidal canal purification device characterized by comprising a controller for activating the ejector for a certain period of time, and levitating suspended matter accumulated at the bottom of the canal and discharging it to the outside of the canal.

According to a fifth aspect of the present invention, there is provided an underwater ejector which is provided in a tidal canal having seawater flowing in and out as the tide is completely exhausted and having a predetermined tidal velocity, and injecting a water flow containing bubbles toward the bottom of the canal. , A driving mechanism for moving the underwater ejector from the upstream side to the downstream side, and an intermittent operation of the underwater ejector while moving the underwater ejector from the upstream side to the downstream side by the driving mechanism at the ebb of a tidal canal. It is a tidal canal purification device that is equipped with a controller that is activated automatically, and that suspends suspended matter that accumulates at the bottom of the canal and discharges it outside the canal.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of a tidal canal purification method and purification apparatus according to the present invention. As shown in Fig. 1, a low tide water level 3 and a high tide water level 14 are set in the tidal canal 1 where seawater flows in and out as the tide goes down, respectively, and on the bay shore 2 of the canal 1 and below the low tide water level 3. The tidal current meter 4 is installed at. The tidal current meter 4 measures the velocity of the tidal current and detects the ebb tide based on the measurement result.

An underwater ejector 5 is arranged about 0.5 m below the low tide water level 3. This underwater ejector 5 has an inflow port 11 provided at an upper part and a nozzle 12 provided at a lower part, and the underwater ejector 5 is connected to the other end of an air intake pipe 10 having one end open to the atmosphere. There is.
Further, the inflow port 11 at the upper part of the underwater ejector 5 is open near the lower part of the low tide water level 3.

Further, a controller 6 is connected to the tide meter 4 and the underwater ejector 5, and when the tide meter 4 detects a low tide, the controller 6 intermittently activates the underwater ejector 5. .

Next, the operation of this embodiment having such a configuration will be described.

Under the condition that the tidal current meter 4 detects the ebb tide from the flow velocity of the tidal current 20 and the flow velocity exceeds a predetermined value, for example, 10% of the maximum flow velocity, the controller 6 causes the underwater ejector 5 to flow.
In response to this, a pulse signal for intermittent activation is output. When the underwater ejector 5 is activated, a water flow 21 containing fine bubbles is jetted from the nozzle 12 toward the bottom of the canal. Then, in a region (hereinafter, referred to as a flow region) 23 where the flow velocity at the bottom of the canal is a predetermined value or more, for example, 100 m / h or more, fine bubbles are formed in the organic suspension layer (sediment) 22 accumulated at the bottom of the canal. Attached,
As a result, the organic suspension layer 22 floats and floats near the water surface.

Generally, the flow velocity near the water surface is higher than that at the bottom. Therefore, the suspended organic suspension (hereinafter, referred to as “suspended suspension”) 24 is easily discharged to the outside of the canal 1 together with the tidal current 20. Underwater ejector 5
By intermittently starting and stopping, the organic suspension layer 22 on the upstream side naturally fills the flow region 23 where the organic suspension layer 22 has already risen so that the upstream organic suspension layer 22 fills the hole previously formed at the time of stop. Move to. Next, the moved organic suspension layer 22 is floated by restarting the underwater ejector 5. By intermittently activating the underwater ejector 5 in this way, the organic suspension layer 22 can be efficiently discharged to the outside of the canal 1.

Generally, the sedimentation rate of organic suspensions is approximately 1.
Since it is about 10 m / h and is extremely easy to float, bottom material does not occur at a place where there is a flow velocity, and it occurs at stagnant areas such as ship pools, river mouths, curved areas, and corner areas. In this example, the properties and flow rate of such an organic suspension are utilized. That is, the underwater ejector 5 is activated at the time of ebb tide, a water flow containing fine bubbles is generated, dissolved oxygen is supplied to the bottom of the canal, and the organic suspension precipitated in the stagnant portion is levitated. Can be carried on the tidal current and easily discharged outside the canal. The organic suspension discharged to the outside of the canal is slowly decomposed by the natural purification power of bacteria, plankton, seafood, etc. under sufficient oxygen dissolved by the waves.

Next, referring to FIGS. 2 and 3, the second aspect of the present invention will be described.
An example will be described. The same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 2, a plurality of underwater ejectors 5 are provided.
.. 5n are sequentially arranged from upstream to downstream. Further, each of the underwater ejectors 5a, 5b, ... 5n and the tidal current meter 4 are connected to the controller 27.

Under the condition that the tidal current meter 4 senses the ebb tide from the tidal current 20 and the velocity exceeds a predetermined value, for example, 10% of the maximum tidal current, the controller 27 activates the underwater ejector 5. The pulse signal of is output. Here, an example of the activation pulse signal output from the controller 27 is shown in FIG. As shown in FIG. 3, the underwater ejectors 5a, 5b, ...
5n is a predetermined time interval t1 (h) and a constant activation time t2 (h), and is activated in the order of the underwater ejectors 5a, 5b, ... 5n, and when the flow velocity of the tidal current 20 is reduced to 10% of the maximum tidal current. Stop and reset.

In this case, after the suspended suspension 24 by the (i-1) th stage underwater ejector 5i-1 flows away in the tidal current 20, the i-th stage underwater ejector 5i is activated, that is, the underwater ejector 5a. , 5b, ..., 5n is L (m), and the tidal current is vf (m / h), by setting the time interval t1-start time t2 ≧ L / vf or more, the suspended suspension 24 Since the backflow can be prevented, the organic suspension can be effectively discharged to the outside.

Next, a third embodiment of the present invention will be described with reference to FIG. The same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 4, a tide gauge 4 is provided on the revetment wall 2 of the canal 1 and below the low water level 3.
A track 30 extends horizontally from the upstream side to the downstream side about 0.5 m below the low water level 3. A waiting point 31 is provided at the upstream end of the track 30 and an end point 32 is provided at the downstream end of the track 30. An underwater ejector 34 having a traveling device 33 is mounted on the track 30, and the underwater ejector 34 travels along the track 30.

Under the condition that the tidal current meter 4 senses the time of ebb from the tidal current 20 and the tidal current exceeds a predetermined value, for example, 10% of the maximum tidal current, the controller 35 activates the underwater ejector 34. A signal is output, the underwater ejector 34 is activated, and the water flow 21 including bubbles is jetted toward the bottom of the canal. At the same time, the traveling device 33 causes the underwater ejector 34 to start moving toward the downstream side to float the organic suspension layer 22 deposited on the bottom. In this case, the moving speed vf (m / h) of the underwater ejector 34 is equal to the tidal current vf.
It is smaller than (m / h). Underwater ejector 3
When 4 reaches the end point 32, the activation of the underwater ejector 34 is stopped, and the underwater ejector 34 returns to the standby point 31. Then, the underwater ejector 34 is activated again to start moving. When the flow velocity decreases and reaches the value of 10% of the maximum power flow, the underwater ejector 34 stops its activation and the standby point 3
Return to 1 and wait.

In FIG. 4, the underwater ejector 34
An air intake pipe 36 is connected to the air intake pipe 36, and the air intake pipe 36 is fixed by a float 37.

Next, a fourth embodiment of the present invention will be described with reference to FIG. The same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 5, a plurality of underwater ejectors 34 are shown.
34n are mounted movably from the upstream side to the downstream side along the track 30, and each underwater ejector 34a, 34b, ... 34n has a traveling device 33.

When the tidal current meter 4 detects the ebb tide from the flow velocity of the tidal current 20 and the flow velocity exceeds a predetermined value, for example, 10% of the maximum tidal current, the controller 40 causes the underwater ejector 34a,
34b, ... 34n, a start signal is output, and at the same time, the traveling device 33 causes the underwater ejectors 34a, 34b ,.
34n is moved along the track 30 from the upstream side to the downstream side in order. All underwater ejectors 34a, 34
34n reach the end point 32, all ejectors 34a, 34b, ...
Return to 1. After that, the underwater ejectors 34a, 34b, ... 3
4n is activated again and starts moving.

When the flow velocity decreases and reaches the value of 10% of the maximum power flow, all the underwater ejectors 34a, 34b, ... 34
The start of n is stopped, and all the machines are returned to the standby point 31 to be on standby. The moving speed vr (m / h) of the underwater ejectors 34a, 34b, ... 34n is smaller than the tidal current vf (m / h). Further, the underwater ejectors 34a, 34b, ... 3
The flow region length of 4n is L2, and each underwater ejector 34a, 34
When the time interval of the start of b, ..., 34n is t3 (h), t3 is set larger than L2 / vf. In this case, after the suspended suspension 24 in the flow region 23 by the (i-1) th stage underwater ejector 34i-n flows away by tidal current,
Since the flow region 23 is formed by the submerged ejector 34i, the backflow of the suspended suspension 24 can be effectively prevented.

In each of the above-mentioned embodiments, an example in which the tidal current meter 4 is used to sense the flow velocity at the ebb tide and the underwater ejectors 5 and 34 are activated is shown, but the tidal current meter 4 is not necessarily required to be used. That is, the low tide time throughout the year is set in advance, a year-round timer is incorporated in the controllers 7, 27, 35, 40 without using the tidal current meter 4, and the underwater ejectors 5, 34 are activated at the predetermined time, and Traveling device 3
You may move 0. In this case, it is possible to avoid a malfunction due to damage of the tidal current meter 4 due to the adhesion of waves and shellfish.

[0029]

As described above, according to the present invention,
By ejecting a water flow containing bubbles to the bottom of the canal, the organic suspension that has settled and deposited on the tidal canal can be floated and discharged easily and easily by the tidal current inside the canal without resorting to dredging. it can. For this reason, the inside of the canal can be maintained in a clean state without producing a sediment composed of an organic suspension in the canal.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a first embodiment of a tidal canal purification method and a purification apparatus according to the present invention.

FIG. 2 is a schematic side view showing a second embodiment of the present invention.

FIG. 3 is a diagram showing a starting pulse signal according to a second embodiment of the present invention.

FIG. 4 is a schematic side view showing a third embodiment of the present invention.

FIG. 5 is a schematic side view showing a fourth embodiment of the present invention.

[Explanation of symbols]

 1 Tidal canal 4 Tidal current meter 5,34 Underwater ejector 6,27,35,40 Controller 22 Organic suspension layer 23 Flow zone 24 Suspended suspension 30 Orbit

Claims (5)

[Claims] 1. A step of arranging an underwater ejector in a tidal canal that has a predetermined tidal velocity as well as inflow and outflow of seawater as the tide ebbs and a step of intermittently activating the underwater ejector during ebb tide A method of purifying a tidal canal, which comprises the steps of injecting a water stream containing the water toward the bottom of the canal, and suspending the suspended sediment that accumulates at the bottom of the canal and discharging it to the outside of the canal. 2. A step of arranging an underwater ejector in a tidal canal having a predetermined tidal velocity, in which seawater flows in and out as the tide goes down, and at the time of ebb tide, the underwater ejector is moved from the upstream side to the downstream side. The method comprises intermittently starting while moving, and injecting a water stream containing bubbles from the underwater ejector toward the bottom of the canal, and floating the suspension accumulated at the bottom of the canal and discharging it to the outside of the canal. A method of purifying a tidal canal characterized by. 3. An underwater ejector, which is provided in a tidal canal having a predetermined tidal velocity and in which seawater flows in and out when the tide is low, and which ejects a water flow containing bubbles toward the bottom of the canal, and a low tide of the tidal canal. A tidal canal purification device, characterized by comprising a controller for intermittently activating the underwater ejector, and causing suspended solids accumulated at the bottom of the canal to float and be discharged to the outside of the canal. 4. The seawater flows in and out as the tide ebbs, and is provided sequentially from the upstream side to the downstream side in a tidal canal having a predetermined tidal velocity, and a water stream containing bubbles is jetted toward the bottom of the canal. A plurality of underwater ejectors, and a controller that sequentially activates each of the underwater ejectors for a certain period of time at a predetermined time interval from the upstream side to the downstream side when the tidal canal ebbs. A tidal canal purification device that is equipped with a suspension system that floats suspended matter that accumulates at the bottom of the canal and discharges it to the outside of the canal. 5. An underwater ejector, which is provided in a tidal canal having a predetermined tidal velocity, in which seawater flows in and out when the tide is completely exhausted, and which ejects a water flow containing bubbles toward the bottom of the canal, and the underwater ejector is located upstream. Drive mechanism for moving the underwater ejector from the upstream side to the downstream side, and a controller for intermittently activating the underwater ejector while moving the underwater ejector from the upstream side to the downstream side by the driving mechanism when the tidal canal ebbs The tidal canal purification device is characterized in that the suspended sediment deposited on the bottom of the canal is levitated and discharged to the outside of the canal.