JPH0747393A - Diffuser type water stream generating device provided in water - Google Patents

Abstract

PURPOSE:To provide the subject device capable of generating a circulating stream into stratification, coping with the dam lake large in water level variation and suppressing the proliferation activity of phytoplanktons. CONSTITUTION:This device has a floating body 1 supporting all of the device at a water surface, a bubble generating device 4 hunged from the floating body 1 by an adjustable wire 5 and a water temp. sensor 2 for controlling the generating state of bubbles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a diffused submerged water flow for suppressing abnormal growth of phytoplankton caused by eutrophication by artificially manipulating the temperature stratification condition in a water area such as a dam lake. Regarding the generator.

[0002]

[Prior art and its problems] Generally, in a water area such as a dam lake, the water temperature is relatively high in a relatively shallow portion due to the influence of the solar heat and the outside temperature, but a certain water depth (thermocline)
When the temperature becomes lower than the following, it is not affected by temperature change and can be divided into a part where the temperature remains relatively low and there is no seasonal change.

In many phytoplankton, photosynthetic activity is actively carried out in the high temperature part of the surface layer (temperature stratification) and in the so-called euphotic layer where sunlight reaches, and the nutrients in the water are taken in and proliferated. A technique for artificially manipulating the temperature stratification state to suppress abnormal growth of phytoplankton caused by eutrophication is known as a fountain device or intermittent air pumping.

The fountain device has a function as a stratification circulation device, and heat is exchanged by pumping low-temperature low-temperature water and sprinkling it in the air, thereby facilitating water temperature adjustment of the stratification and lowering of the thermocline. is there. Further, by making the water absorption point of the pump shallower, the plankton in the water is sucked, and the pressure is increased by the pump, which damages the plankton and suppresses the growth ability.

However, the fountain device requires a large amount of power for damage due to pressurization of plankton and water sprinkling into the air, so that the pump power is relatively large. Therefore, the energy used for circulation in the stratification is relatively large.

Since the intermittent pumping cylinder is connected to the anchor provided at the bottom of the water, it has poor vertical mobility with respect to changes in the water surface, and is not suitable for dam lakes and the like where large water level fluctuations occur. In addition, there is a possibility of destroying the thermocline due to the generation of large convection.

Further, since the convection due to the bubble bullet is generated intermittently, there is a problem that the interval for the bubble bullet to be extended becomes longer for a small amount of air supply, so that the time interval for generating the convection becomes longer.

The pump-type water flow generator has many advantages because it is easy to control the amount of water for convection and the supply of deep water to lower the stratocline, and has many advantages. However, entrainment is effectively used in water. Not not. The jet flow velocity injected from the pump nozzle becomes slower as it moves away from the nozzle, so the entrainment force becomes weaker.

On the other hand, since the water flow generated by the bubbles utilizes the force of the bubbles as they rise and the bubbles rise, the entrainment force increases.

[0010]

SUMMARY OF THE INVENTION Therefore, the present invention provides a diffuser type underwater flow generator capable of efficiently generating a circulating flow in a stratified layer and coping with a dam lake having a large fluctuation in water level and capable of suppressing the growth activity of phytoplankton. It is intended to be provided.

[0011]

According to the present invention, in a diffuser type underwater flow generator having a floating body for supporting the entire apparatus on the water surface, a bubble generating apparatus suspended from a floating body by an adjustable cord. , And a water temperature sensor for controlling the generation state of bubbles.

Further, according to the present invention, in the diffuser type underwater water flow generating device having the floating body for supporting the entire apparatus on the water surface, the second bubble generating the convection suspended by the adjustable rope from the floating body. From the generator and the first bubble generator that generates an upward flow due to the fall of the stratum corneum, and from the temperature sensor and the switching means that adjusts or switches the operating conditions of the first and second bubble generators according to the signal from the temperature sensor. It is configured.

[0013]

[Explanation of action and effect] In the diffuser type underwater flow generator configured as described above, initially, the diffuser pipe is installed at a deep position to efficiently generate a water flow with a strong entrainment force, and the temperature sensor causes a predetermined jump. When it is detected that the stratification has been achieved, the air diffuser is moved upward, and the convection in the surface layer is continuously generated by operating near the predetermined stratocline.

Further, a first air diffuser and a second air diffuser are provided, the second air diffuser is installed in the vicinity of a predetermined stratocline, and the first air diffuser is used for the period of lowering the stratocumulus and the water level of the dam lake. It will be installed at the water level decided from. Then, when the temperature sensor detects a predetermined fall of the stratum corneum, the first diffuser pipe may be switched to the second diffuser pipe to generate convection in the surface layer.

Due to such an action, it is possible to prevent an excessive decrease in the stratum corneum and to continuously and efficiently generate convection in the surface layer.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, an air diffuser 4 is suspended from one end of a suspending wire 5 from a floating body 1 having a plurality of supporting floats 1a, and the other end of the wire 5 is connected to a winch 7 on the floating body 1.

A plurality of (three in the illustrated example) temperature sensors 2 are provided between the air diffuser 4 and the floating body 1 at predetermined water depths.

From the air compressor 6 installed on land, the air pipe 3 is connected to the air diffuser pipe 4 via the water.

The operation will be described below.

Initially, the air diffuser 4 is hung by the winch 7 to a water depth C deeper than the layer-descending target water depth A. Therefore, the air compressor 6 is operated to supply air to the air diffuser 4. Since the water depth is sufficiently deep, the bubbles exert sufficient entrainment ability and generate a strong upward flow.

When the temperature sensor 2 at a predetermined water depth reaches a predetermined value,
Winches 7 when it is judged that the target water depth A for the decline
If the diffusing pipe 4 is raised by fixing it to the water depth A and switching to the operation for circulation in the surface layer, convection in the surface layer above the target stratocline is continued and phytoplankton growth is prevented. To be done.

FIG. 2 shows a second embodiment of the present invention, in which a floating body 11 supported by a plurality of support floats 11a is suspended by a winch 17 to a predetermined depth and is suspended by a wire 5 in a first air diffusing tube. 14 and the second air diffuser 1 suspended at the stratospheric target water depth
5 and are installed.

A plurality of (four in the illustrated example) temperature sensors 12 are provided between the air diffuser and the floating body 11. The air diffuser 14 is switched to the air tube 13a and the air diffuser 15 is switched to the air tube 13b. It is connected to the air compressor 6 via a valve 8.

The operation will be described below.

Initially, the first air diffuser 14 is supplied with air from the air compressor 6 through the switching valve 8 to generate bubbles from a deep water position as in the first embodiment. When the temperature sensor 12 detects that the stratum corneum has reached a predetermined depth, the second diffuser 15
The switching valve 8 is switched so as to supply air.

Since the second diffuser pipe 15 is installed at the target water layer for the stratum corneum, if the operation is continued as it is, convection occurs in the surface layer without deepening the stratum corneum.

[0028]

Since the present invention is configured as described above, in order to lower the stratum corneum to the target water depth, the bubble generating device is installed at a deep water depth to effectively utilize the entrainment action, When the stratum reaches the target water depth, the bubble generator can be operated at that depth to continuously generate stratified convection, so that the growth of phytoplankton can be prevented without destroying the stratum crescent.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an air diffusing bubble generator showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of a bubble generating device showing a second embodiment of the present invention.

[Explanation of symbols]

 1, 11 ... Floating body 2, 12 ... Temperature sensor 3, 13 ... Air pipe 4 ... Diffuser pipe 5 ... Suspension wire 6 ... Air compressor 7 ... Winch 8 ... Switching valve 14 ... First diffuser pipe 15 ... Second Air diffuser

Claims (2)

[Claims] 1. An air diffuser type underwater water flow generator having a floating body for supporting the entire apparatus on the water surface, and a bubble generator suspended by an adjustable rope from the floating body, and a state for generating bubbles. An air diffuser type underwater flow generator comprising a water temperature sensor. 2. A diffuser type underwater water flow generator having a floating body for supporting the entire apparatus on the water surface, and a second bubble generator for generating convection suspended by a rope adjustable from the floating body and a stratospheric fall. Therefore, it is configured by a first bubble generating device for generating an upward flow, a switching means for adjusting or switching the operating conditions of the first and second bubble generating devices in response to a signal from the temperature sensor, and a temperature sensor. A diffuser type underwater flow generator.