JPH08164188A - Laser irradiation device for method for preventing adhesion of living things in water pipe - Google Patents

Abstract

PURPOSE: To provide a laser irradiation device in a method for preventing the adhesion of living things in a water pipe capable of increasing a water pass rate without degrading the intensity of a laser beam. CONSTITUTION: This laser irradiation device consists of a water pipe 1 to be irradiated and a laser generator 2. The water pipe 1 to be irradiated is provided with spiral partitions 8 for forming spiral aquatic living things-contg. water passages between the outside cylinder 6 and inside cylinder 7 of double cylindrical pipes consisting of an outside cylinder 6, an inside cylinder 7 and right arid left end walls 9, 10. The laser generator 2 is arranged outerward at the left end of the water pipe 1 to be irradiated and casts the laser beam parallel with the axial line between the outside cylinder 6 and the inside cylinder 7. The left end wall 9 of the water pipe 1 to be irradiated is provided with a laser beam incident window 3 and the partitions 8 are provided with laser beam transmission windows 11 at the points corresponding to the laser beam passages of the partitions 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to equipment, pipes, and water pipes (collectively referred to as "water pipes") of nuclear power plants, thermal power plants, or various factories that use a large amount of fresh water or seawater. , Aquatic animals such as mussels and oysters and oysters and aquatic animals such as barnacles or their larvae, aquatic plants such as algae, and organisms with ecological adhesiveness such as aquatic microorganisms (collectively referred to as "aquatic organisms") The present invention relates to a laser irradiation device used in a method for preventing the attachment of aquatic organisms, which prevents the aquatic organisms from attaching to, growing and reproducing.

[0002]

2. Description of the Related Art Conventionally, as a laser irradiation device in a method for preventing attachment of living things in a water pipe, Japanese Patent Application Laid-Open No. 5-22845
Japanese Patent Publication No. 4 discloses a device as shown in FIG. This laser irradiation device is disposed on an irradiation water pipe (21) having an entrance window (23) at one end and an axial extension of the irradiation water pipe (21) toward one end, and the irradiation water pipe (21) passes through the entrance window (23). ) Is provided with a laser generator (22) for irradiating a laser beam, and an inlet (24) is provided at the lower end of one end of the irradiation water pipe (21).
An outlet (25) is provided on the upper end of the other end so that water containing aquatic organisms flows in the optical axis direction of the laser beam.

[0003]

By the way, in this type of laser irradiation apparatus, increasing the amount of water passing through the irradiation water pipe, that is, the amount of laser treatment, the time during which the water containing aquatic organisms stays in the irradiation water pipe, That is, it is very important to lengthen the irradiation time and thereby enhance the irradiation effect. In the above conventional laser irradiation device, in order to increase the amount of water passing through the irradiation water pipe, that is, the amount of laser treatment, it is necessary to increase the diameter of the irradiation water pipe, in which case the irradiation area of the laser will expand. There was a problem that the irradiation intensity of the laser must be increased to match it. Further, in the conventional laser irradiation device, in order to lengthen the irradiation time and enhance the irradiation effect, it is necessary to lengthen the irradiation water pipe, but there is a restriction that it can be kept within a practical length, and the irradiation effect is not sufficient. There was also the problem that things could not be made.

The object of the present invention is to increase the amount of water passing through the irradiation water pipe without increasing the irradiation area of the laser, and to keep the irradiation water pipe in a practical length and to extend the irradiation time. It is therefore to provide a laser irradiation device in a method for preventing adhesion of living things in a water pipe, which can enhance the irradiation effect.

[0005]

A laser irradiating device in a method for preventing adherence of organisms in a water pipe according to the present invention comprises a double cylindrical pipe consisting of an outer cylinder, an inner cylinder and an end wall between the outer cylinder and the inner cylinder. Irradiation water pipe provided with a partition forming a spiral water path containing aquatic organisms, and a laser beam parallel to the pipe axis is disposed between the outer cylinder and the inner cylinder, which is arranged outside one end of the irradiation water pipe. The irradiation water pipe is provided with a laser beam entrance window on one end wall and a laser beam transmission window on the partition.

The laser generator may include a plurality of laser oscillators.

[0007]

According to the laser irradiation apparatus in the method for preventing adhesion of living organisms in a water pipe of the present invention, while the water containing aquatic organisms flows through the spiral passage, the laser beam is irradiated and the aquatic organisms are killed and damaged. , The attachment of organisms in the water pipe is prevented. The amount of water passing through the irradiation water pipe can be adjusted by adjusting the width of the spiral passage, and since the passage is spiral, passage time (laser irradiation time) in the irradiation water pipe can be gained.

Further, the flow velocity in the irradiation water pipe can be reduced by widening the width of the passage. In particular, it is possible to reduce the flow velocity on the inlet side where the laser irradiation effect is high.

If the laser generator comprises a plurality of laser oscillators, the irradiation effect can be further enhanced.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In the following description, upper, lower, left, and right mean the upper, lower, left, and right in FIG.

FIG. 1 and FIG. 2 show an embodiment of a laser irradiation device in a method for preventing adhesion of organisms in a water pipe according to the present invention. An irradiation water pipe (1) extending left and right and an irradiation water pipe (1) are shown. And a laser generator (2) arranged outside the left end of the.

The irradiation water pipe (1) is composed of an outer cylinder (6), an inner cylinder (7) and left and right end walls (9) and (10), a double cylindrical tube, an outer cylinder (6) and an inner cylinder (7). And a spiral partition (8) disposed between and forming a spiral passage. An inlet (4) is provided at the lower left end of the outer cylinder (6), and an outlet (5) is provided at the upper right end of the outer cylinder (6) .The water containing aquatic organisms introduced from the inlet (4) is The partition (8) guides the space between the inner cylinder (7) and the inner cylinder (7) to flow spirally, and is discharged from the outlet (5).

The laser generator (5) irradiates a laser beam parallel to the tube axis direction between the outer cylinder (6) and the inner cylinder (7) of the irradiation water pipe (1). , Irradiation water pipe (1)
1 laser transmitter that irradiates a laser beam on the upper part of the
I have one.

On the upper part of the left end wall (9) of the irradiation water pipe (4), an entrance window (3) made of glass for entering a laser beam is provided.
A glass transmission window for laser beam transmission is provided at the laser beam passage of the partition (8) of the irradiation water pipe (4).
(11) is provided.

The laser beam emitted from the laser oscillator passes through the entrance window (3) between the outer tube (6) and the inner tube (7) of the irradiation water pipe (1) and passes through the window ( From 12),
During this time, the water containing aquatic organisms is irradiated from a direction substantially perpendicular to the water flow direction.

The pitch of the spiral passage can be appropriately changed according to the required performance. For example, in order to increase the water flow rate, the pitch is increased to widen the water flow path width of the spiral passage. By doing so, it is not necessary to increase the area to be irradiated with the laser, and it is possible to increase the water flow rate without lowering the intensity of the laser beam. In addition, to increase the water flow rate,
It is also possible to increase the inner diameter of (6), reduce the outer diameter of the inner cylinder (7), or increase both the outer cylinder (6) and the inner cylinder (7).

According to the above laser irradiation device, since the water containing aquatic organisms flows through the spiral passage, the time for which the water containing aquatic organisms stays in the irradiation water pipe (1) becomes long and the irradiation effect is enhanced. Also, in the conventional laser irradiation device, when trying to use a large diameter irradiation water pipe (21) in order to increase the water flow rate,
In response to this, the area to be irradiated with the laser is expanded, and it is necessary to expand the laser beam in a wider range. Therefore, there is a problem that the intensity of the laser beam is reduced by expanding the laser beam. In the irradiation device, it is not necessary to increase the area to be irradiated with the laser in order to increase the water flow rate, and the water flow rate can be increased without lowering the intensity of the laser beam.

In the laser irradiation device having the above-mentioned structure, natural seawater is passed through the irradiation water pipe (4) and irradiated with a laser beam to measure the amount of marine organisms attached in a monitor water tank provided downstream (wet The weight was measured, the unit was gram, and the effect of the laser beam on marine organisms was investigated. For comparison, FIG.
The conventional laser irradiation device shown in FIG. 3 and the case where no laser irradiation was performed were also observed, and the observation results are shown in FIG.

As shown in FIG. 3, in comparison with the case of no irradiation, in the device of the comparative example, 1/2 or more of the marine organisms survive, but in the device of the present invention, it is only 1/4 or less. It can be seen that the non-viable device of the present invention caused greater killing damage to marine organisms than conventional devices.

In the embodiment shown in FIG. 1, only one laser transmitter of the laser generator (5) is provided so as to irradiate the upper part of the irradiation water pipe. However, for example, the lower part of the irradiation water pipe is irradiated. One more may be added as described above, or more may be added. By providing a plurality of laser oscillators, the irradiation effect can be further enhanced.

FIG. 4 shows another embodiment of the laser irradiation apparatus of the present invention. This device is different from that shown in FIG. 1 in that the spiral partitions (8) (18) that are arranged between the outer cylinder (6) and the inner cylinder (7) of the irradiation water pipe form a spiral passage. ing. The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. The partition (18) of this embodiment is gradually reduced as the pitch of its spiral goes from left to right. Therefore, the width of the water passage is large near the entrance, and the residence time of the water containing aquatic organisms becomes long near the entrance where the laser irradiation effect is high. As a result, the laser irradiation time of the water containing aquatic organisms becomes longer, and the irradiation effect can be enhanced.

In the above embodiment, the type of laser that can be used includes an argon ion laser, a copper vapor laser, a YAG laser, a semiconductor laser and a nitrogen laser. These lasers are used alone or in combination. The main factors that cause the laser irradiation to cause a killing effect on aquatic organisms include a laser wavelength, light energy per unit area of irradiation, and the like. Argon ion lasers and copper vapor lasers are particularly suitable because they have a very low water absorption due to the characteristics of each wavelength and therefore have good water permeability and can directly kill and damage aquatic organisms. is there. The wavelength of the laser that can be used is in the range of 350 to 1000 nm, but in consideration of absorption into water, direct absorption into the living body, etc., 4
Lasers having a wavelength in the range of 00 to 700 nm are preferred.

[0023]

According to the laser irradiation apparatus in the method for preventing adhesion of organisms in the water pipe of the present invention, the amount of water passing through the irradiation water pipe can be adjusted by adjusting the width of the spiral passage.
The amount of water passing through the irradiation water pipe can be increased without increasing the irradiation area of the laser. Since the passage time (laser irradiation time) in the irradiation water pipe can be earned, the irradiation effect can be enhanced by keeping the irradiation water pipe within a practical length and increasing the irradiation time. Furthermore, by increasing the width of the passage, it is possible to reduce the flow velocity in the irradiation water pipe, and it is possible to reduce the flow velocity especially at the entrance side where the laser irradiation effect is high, so the passage time (laser irradiation time) in the irradiation water pipe can be reduced. It can be longer and the bactericidal effect of organisms in the water pipe is increased.

When the laser generator is equipped with a plurality of laser oscillators, the irradiation effect can be enhanced, and the sterilizing effect on the organisms in the water pipe is further enhanced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view schematically showing one embodiment of a laser irradiation apparatus in a method for preventing adhesion of living things in a water pipe according to the present invention.

FIG. 2 is a transverse sectional view of the same.

FIG. 3 is a graph showing the relationship between laser irradiation and the number of surviving aquatic organism-attached individuals.

FIG. 4 is a vertical sectional view schematically showing another embodiment of the laser irradiation apparatus according to the present invention.

FIG. 5 is a vertical sectional view schematically showing a conventional laser irradiation device.

[Explanation of symbols]

 (1) Irradiation water pipe (2) Laser generator (3) Laser beam entrance window (6) Outer cylinder (7) Inner cylinder (8) (18) Partition (9) (10) End wall (11) Laser beam transmission window

Claims (2)

[Claims] 1. An outer cylinder (6), an inner cylinder (7) and end walls (9) (10).
An irradiation water pipe (1) provided with partitions (8) (18) that form a spiral water passage containing aquatic organisms between the outer cylinder (6) and the inner cylinder (7) , A laser generator (2) that is arranged outside one end of the irradiation water pipe (1) and irradiates a laser beam parallel to the pipe axis between the outer cylinder (6) and the inner cylinder (7). Laser beam entrance window on one wall (9) of the water tube (1)
(3) A laser irradiation device in a method for preventing adherence of living organisms in a water pipe, wherein a laser beam transmission window (11) is provided on each of the partitions (8) and (18). 2. The laser irradiation device in the method for preventing adherence of organisms in a water pipe according to claim 1, wherein the laser generator (2) comprises a plurality of laser oscillators.