JPH0194997A - Method for preventing fouling by marine organisms - Google Patents

Abstract

PURPOSE:To prevent the fouling of marine organisms, by using a specific amount of hydrogen peroxide and catalase in seawater. CONSTITUTION:0.05-3.5ppm of hydrogen peroxide and 0.01ppm or more (50000 unit of liquid catalase) of catalase are together added to seawater. By this method, the fouling by marine organisms can be effectively prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for preventing the adhesion of seawater organisms, and particularly to a method for effectively preventing the adhesion of seawater organisms such as mussels to plants that use seawater. Concerning how to suppress.

[Conventional technology] Thermal power plants that use large amounts of seawater as one-time cooling water;
In steel plants, petrochemical industries, etc., seawater organisms such as mussels, fujibos, and hydrozoans adhere to the channels and heat exchangers of these cooling water systems, resulting in clogging of pipes, reductions in the amount of seawater sampled, and reductions in cooling efficiency. This may lead to various problems such as functional deterioration such as deterioration or even damage to the device.

Conventionally, in order to prevent damage caused by these attached organisms,
Chlorine, formalin, organotin compounds, organic sulfur compounds, quaternary ammonium salts, and the like have been used, but there are concerns that these drugs have cumulative toxicity to fish and the like, and environmental destruction due to residual toxicity.

On the other hand, methods to improve such toxicity problems include the use of hydrogen peroxide (Japanese Patent Publication No. 61-2439) and the combination of hydrogen peroxide and iron ions (Japanese Patent Publication No. 6O-10).
6584) has been proposed.

[Problems to be Solved by the Invention] However, the method of adding hydrogen peroxide disclosed in Japanese Patent Publication No. 61-2439 does not provide a sufficiently satisfactory effect and requires the use of a large amount of hydrogen peroxide. Incidentally, in Japanese Patent Publication No. 61-2439, it is said that the effect will appear if the concentration of hydrogen peroxide in seawater is maintained at 0.01 to 500 ppm, but the practical concentration according to specific examples is that it is necessary to continuously inject 3.5 ppm or more. There is.

Furthermore, in the method disclosed in JP-A-60-106584 in which iron ions are used in combination, the practical concentration of hydrogen peroxide is reduced to some extent, but a sufficient effect has not yet been obtained.

[Means for Solving the Problems] The present invention solves the above-mentioned conventional problems and provides a method for effectively preventing the adhesion of seawater organisms using a small amount of chemicals.

The method for preventing adhesion of seawater organisms of the present invention is characterized by using hydrogen peroxide and catalase.

In other words, as a result of intensive studies aimed at significantly improving the conventional effective amount of hydrogen peroxide added, the inventors found that hydrogen peroxide can be reduced by combining catalase, which does not show the effect of preventing the adhesion of seawater organisms when used alone. The present invention has been completed based on the discovery that it is possible to significantly reduce the amount of use of and obtain significantly superior effects.

The present invention will be explained in detail below.

The method of the present invention uses catalase together with hydrogen peroxide.

In the present invention, the amount of hydrogen peroxide used is 0.05 ppm (0.15 ppm as 35% H2O2) relative to seawater.
)~3.5ppm (10ppm as 35% H2O2)
It is preferable that Hydrogen peroxide concentration is 0. O5ppm
If it is less than 3.5 ppm, a sufficient adhesion prevention effect may not be obtained, and if it exceeds 3.5 ppm, the amount of hydrogen peroxide will be large, making it uneconomical.

The amount of catalase used in combination with hydrogen peroxide varies depending on its activity; for example, if 50,000 units of liquid catalase is used, a sufficient effect can be obtained by using 0.01 ppm or more relative to seawater. That is, since catalase is indicated by activity and cannot be expressed simply by concentration, in the present invention, the preferred amount of catalase to be used is expressed as 01PPrn or more when converted to 5oooo units of catalase. Therefore, in the case of catalase with ioooo units, it is preferable to use 0.05 ppm or more. Catalase is preferably added in an amount of 0.01 to 0.5 ppm, particularly as 50,000 units of catalase.

In carrying out the present invention, it is effective to continuously inject hydrogen peroxide and catalase together, but if catalase and hydrogen peroxide come into contact before injection, catalase will absorb hydrogen peroxide. Because of their decomposition, it is important to add both drugs separately using a two-part injection.

[Effect] By using hydrogen peroxide and catalase together, the amount of hydrogen peroxide used can be significantly reduced, and an excellent effect of preventing the adhesion of seawater organisms can be achieved.

Catalase is a substance that exists in living organisms, and is even safer than iron ions, etc., and has no problems such as toxicity.

[Examples] The present invention will be described in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited to the following Examples unless it exceeds the gist thereof.

Example 1.2, Comparative Examples 1 to 7 Using the model waterway 1 shown in FIG. 1 during the mussel adhesion breeding season, the effects of the chemicals shown in Table 1 on preventing the adhesion of seawater organisms were investigated. In FIG. 1, 2 is a submersible pump that supplies seawater to the model waterway 1. 3 is a drug tank, and the stored drugs are supplied to the model waterway 1 by a chemical pump (not shown). Note that 4 is a branch header.

A 1010 x 10 PVC adhesion plate was immersed near the outlet side of this model waterway, and seawater was flowed at a flow rate of approximately 0.4 m/sec.
Water was passed through at step c, and the chemicals shown in Table 1 were injected from the chemical tank 3 at the rates shown in Table 1 using a chemical pump.However, in Comparative Example 1, no chemicals were used. ), 6
The number of mussels attached after 0 days was measured and converted to 1 mussel.

The results are shown in Table 1.

Note that 35% H202 was used as hydrogen peroxide, Fe50+.7H20 was used as ferrous sulfate, and 50,000 units of catalase was used as catalase.

Table 1 Examples 3 to 7, Comparative Examples 8 to 11 The chemicals shown in Table 2 were injected at the rates shown in Table 2 during the attaching breeding season of Fujibbo (however, Comparative Example 7 did not use any chemicals). In the same manner as in Example 1, the effect of preventing the adhesion of mussels and Fujitbo was investigated.

The flow rate was approximately 0.3 m/sea, and the test period was 80 m/sea.
It was a day.

The results are shown in Table 2.

Table 2 The following is clear from Tables 1 and 2.

That is, when hydrogen peroxide is used alone, practical effects cannot be obtained unless a high concentration of 5.0 ppm or more is used.

Although the amount of hydrogen peroxide used can be reduced by the combined use of ferrous sulfate, the combined use of catalase of the present invention can further reduce the amount of hydrogen peroxide used, resulting in significantly superior effects. Incidentally, catalase alone does not have the effect of preventing adhesion of seawater organisms (Comparative Example 7).

[Effects of the Invention] As detailed above, the method for preventing adhesion of seawater organisms of the present invention uses hydrogen peroxide and catalase, and has an extremely excellent adhesion prevention effect with an extremely small amount of hydrogen peroxide used. can be obtained.

Moreover, since the chemicals used in the method of the present invention have no toxicity problems, they can effectively prevent seawater biofouling problems in seawater plants, etc., without causing environmental pollution.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing a seawater-type model waterway used in Examples and Comparative Examples of the present invention. 1... Model waterway, 2... Submersible pump, 3...
・Medical tank. Agent Patent Attorney Tsuyoshi Shigeno Figure 1

Claims (1)

[Claims] (1) A method for preventing adhesion of seawater organisms, characterized by using hydrogen peroxide and catalase. (2) For seawater,
2. Process according to claim 1, characterized in that 0.05 to 3.5 ppm of hydrogen peroxide is added. (3) The method according to claim 2, characterized in that catalase is added to seawater in an amount of 0.01 ppm or more in terms of 50,000 units of catalase.