JPH01274395A - Preventing method for adhesion of sea-organism - Google Patents

Abstract

PURPOSE:To make it possible to prevent the adhesion of sea-organisms to the structure of a sea water channel by applying a very narrow high voltage pulse several times repeatedly to the sea water passing through the entrance portion or the inner portion of the structure of the sea water channel. CONSTITUTION:Larvae of adhesive sea-organisms in the sea water flowing in from the sea water intake 1 are applied with a very narrow high voltage pulse several times repeatedly when passing through a device 5 for applying a very narrow high voltage pulse, and they are kept in paralysis continually or killed and eliminated. Therefore the adhesion and the growth of the larvae to and on the wall of the water intake 2 or the intake side tube channel 4 can be prevented. Under the application of the very narrow high voltage pulse of only one time, the larvae are once paralyzed but recover the activity with time, but by applying the said pulse several times repeatedly the larvae are kept in paralysis continually or killed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for preventing the adhesion of marine organisms suitable for the maintenance and management of seawater channel structures such as seawater pipes and heat exchangers that use seawater that come into contact with seawater. .

[Conventional technology]

In seawater inlet pipes, heat exchangers and plants that use seawater as cooling water, phenomena such as marine organisms adhering to or growing in the seawater flow path increase flow path resistance and heat transfer resistance, causing severe damage. In some cases, the flow path itself may be blocked. For this reason, mercury has traditionally been used as a chemical antifouling method for structures in the seawater flow path.

Applying antifouling paint containing compounds such as arsenic, copper, and organic tin, injecting drugs such as sodium chlorine hypochlorite into seawater, or electrolyzing seawater itself as an electrolyte and using a cathode to Methods are being used to kill attached sea creature larvae, such as by utilizing the effects of generated chlorine and chlorate ions. Furthermore, physical antifouling methods include ultrasonic application and ultraviolet irradiation.

There is an increase in flow velocity, etc.

However, the conventional method has the following problems.

(1) Regarding chemical antifouling methods, chlorine,
Since substances such as tin and copper are mixed in, there is an environmental protection problem.

(2) Physical antifouling methods have problems such as high energy consumption and increased power costs.

[Problem to be solved by the invention]

The present invention was proposed in view of these circumstances, and
It is possible to accurately kill or paralyze sea creatures and prevent them from adhering to seawater channel structures, thereby reducing channel resistance in seawater channel structures.

To provide a method for preventing the adhesion of marine organisms from lying on the seabed, which can prevent an increase in heat transfer resistance and the occurrence of a clogging phenomenon, and which does not introduce harmful substances into seawater, eliminates environmental protection problems, and eliminates excessive energy consumption. The purpose is to

[Means to solve the problem]

To this end, the present invention is characterized in that extremely short high voltage pulses are repeatedly applied multiple times to the seawater passing through the seawater inlet portion or inside of the seawater channel structure.

[For production]

In the method of the present invention, high voltage and high current flow inside the body of the larva due to the high voltage applied when the larva of the attached sea creature passes through the electrode provided at the seawater inlet of the seawater channel structure or inside the seawater channel structure. As a result, the larvae become paralyzed or die. Therefore, it is possible to prevent the adhesion and growth of marine organisms to seawater channel structures, reduce channel resistance,
It is possible to eliminate various adverse effects such as forces that increase heat transfer resistance and blockage of the flow path itself.゛ [Example] An example in which the method for preventing the adhesion of marine organisms of the present invention is applied to a cooling seawater system of a power plant will be explained with reference to the drawings. Figure 1 is a schematic diagram of the cooling seawater system, and Figure 2 is a schematic diagram of the cooling seawater system, and Figure 2 is a schematic diagram of the cooling seawater system of a power plant. FIG. 3 is a schematic diagram of the experimental equipment for confirming the effect, and a diagram showing the results.

First, in Figure 1, 1 is the seawater intake, 2 is the intake channel, and 3
4 is a circulating water pump, 4 is a water intake side pipe, 5 is a plurality of ultra-short high voltage pulse application devices installed at appropriate intervals between the intake channel 2 and the water intake side pipe 4, 6 is an ultra-short high voltage pulse 7 is a condenser, 8 is a cooling water system cooler, 9 is a water discharge side pipe,
10 is a water discharge side waterway.

In such a device, when the larvae of sea creatures attached to the seawater flowing in from the seawater intake port 1 pass through the short high voltage pulse application device 5, extremely short high voltage pulses are repeatedly applied to them multiple times. As a result, the paralytic state may persist or the fish may die, thereby preventing the growth of adhesion to the walls of the intake channel 2 and intake pipe 4. Note that with one application of an extremely short high voltage pulse, even if the animal is paralyzed for a few moments, it regains its activity over time, but if it is applied multiple times, the paralyzed state continues or it dies. Furthermore, by adjusting the charging conditions, the degree of damage to marine larvae can be adjusted.

Next, an example of an experiment for confirming the paralytic state of marine larvae in the above embodiment will be described below.

Figure 2 shows an experimental setup in which extremely short high voltage pulses were applied using Fujibbo nauplius larvae as a representative of larvae of sessile sea creatures. Reference numeral 6 denotes an extremely short high voltage pulse generation power source, 5a a high voltage electrode, 5b a ground electrode, and 5C a container (length 1 oasts, width 2011 m, height 10 dragons) in which the test larvae are placed. Therefore, 20 to 30 Fujibbo nobrius larvae were placed in the sample solution 11 of the container 5C, and the electric field strength was 1.
, OKV/cR, and a pulse width of 750 ns, the paralysis rate is 90% immediately after application, as shown in Figure 3, a relationship between the paralysis rate of marine life larvae and the recovery time after pulse application. , it decreases to 60% after 5 minutes. However, as shown in FIG. 3, when a pulse is applied under the same conditions after 5 minutes, the paralysis rate becomes 90% again, and if this is repeated, a paralysis rate of 60 to 90% can always be obtained.

In this way, by repeatedly applying pulses multiple times, it is possible to maintain a high paralysis rate of marine life larvae, effectively preventing marine life from adhering, and enabling long-term continuous operation of the cooling seawater system. becomes.

〔Effect of the invention〕

In short, according to the present invention, at the seawater inlet of a seawater channel structure or inside the seawater channel structure, by repeatedly applying extremely short high voltage pulses to the seawater flowing through the same part, marine life can be accurately killed. It is possible to prevent adhesion to seawater channel structures by killing or paralyzing it, and it is possible to prevent increases in channel resistance and heat transfer resistance in seawater channel structures and the occurrence of blockage phenomena, and There is no mixing of harmful substances into the water, there are no environmental protection issues, and there is no excessive consumption of energy! (The present invention is industrially extremely useful because it provides a method for preventing the adhesion of marine organisms.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an implementation apparatus in an embodiment in which the method for preventing marine life adhesion of the present invention is applied to a cooling seawater system of a power plant, and Fig. 2 is a schematic diagram of an experimental apparatus for confirming the effect of the same. , FIG. 3 is a diagram showing the results. 1... Seawater intake, 2... Hydration channel, 3... Circulating water pump, 4... Water intake side pipe, 5... Very short high voltage pulse application device, 6... Very short High voltage pulse generation power supply, 7.
... Condensate channel, 8... Cooling water system cooler, 9... Water discharge side pipe, 10... Water discharge side channel, 5a... High voltage electrode,
5b... Earth electrode, 5C... Container for holding test larvae, 11... Sample solution. Agent Masa Tsukamoto, Patent Attorney Figure 2 Figure 3

Claims (1)

[Claims] A method for preventing the adhesion of marine life, characterized by repeatedly applying extremely short high voltage pulses to the seawater passing through the seawater inlet portion or inside of a seawater channel structure over a plurality of times.