JP2014005430A - Disinfectant anticorrosive and deterioration prevention method for iron and concrete structure - Google Patents

Abstract

[Problem] When coated on iron and concrete structures, it has good adhesion over a long period of time, yet has a sufficient anti-degradation effect even in an oxidative and corrosive environment caused by microorganisms, and is not easily affected by adhesion of algae, crustaceans, etc. An anticorrosive and a method for preventing deterioration are provided.
Disclosed is a bactericidal and anticorrosive agent characterized in that at least a fluororesin and a copper complex, titanium, titanium oxide powder and an uncured acid-resistant cement or mortar are dispersed in water. This is a deterioration prevention method in which a bactericidal and anticorrosive agent obtained by adding and blending any one of water-soluble polymers is applied to the surfaces of iron and concrete structures and cured.
[Selection figure] None

Description

The present invention is used for water treatment facilities such as water and sewage systems, agricultural waterways, fish farm tanks, power plants and chemical factories, food factories and other water intakes, drainage channels and water tanks, etc. The present invention relates to a bactericidal and anticorrosive agent for preventing deterioration (neutralization) and a method for preventing deterioration.

In water treatment facilities such as water and sewage systems, agricultural waterways, fish farm water tanks, power plants and factories, and drainage channels, oxidative degradation (neutrality) of algae and crustaceans due to biofouling and microbial growth Is a problem.
In sewage treatment facilities, hydrogen sulfide generated by the metabolic action of a kind of microorganisms inhabiting sewage and sewage sludge, sulfate-reducing bacteria, which are anaerobic bacteria, is the main cause.
Furthermore, in the intake and drainage channels of fish tanks, power plants, factories, etc., the generation of algae and crustaceans is often caused by organic acids produced by their metabolites.
In response to this situation, the following has been proposed as a method for preventing oxidative deterioration of concrete structures.
1. A method of preventing the generation of hydrogen sulfide by preventing sewage rot.
2. A method to prevent the generated hydrogen sulfide from diffusing into the atmosphere.
3. A method for suppressing the generation of sulfur-oxidizing bacteria that produce sulfuric acid based on hydrogen sulfide.
4). A method to prevent adhesion of algae and crustaceans with paint containing poisonous substances.
5. A method of lining (coating) by applying sterilizing paint or anti-corrosion paint to the surface of iron or concrete or attaching a vinyl sheet or the like.

Japanese Patent No. 2880887 Japanese Patent No. 2543794

In the above method 1, since sewage and sludge are contained in the sewage, it is impossible to completely remove the sewage and sludge, and a satisfactory effect is not obtained.

The second method involves immobilizing hydrogen sulfide by adding a chemical agent such as an oxidizer (hydrogen peroxide, etc.). However, this method is expensive and requires special care for handling. There's a problem.

Method 3 is known to supply and exhaust air in the facility and dilute hydrogen sulfide. Hydrogen sulfide gas is one of the eight malodorous substances defined by the Malodor Control Law. Therefore, if it exhausts, a pollution environmental problem will arise, and if it is 10 ppm or more as a work environment, a health problem will arise, and if it becomes further high, it will die and there is a danger of an explosion, and implementation is difficult.

In method 4, as a means to prevent the attachment of algae and crustaceans, a toxic chemical such as cuprous oxide or organic tin is mixed into the paint, for example, it is applied to concrete or the bottom of the ship, and the poison is gradually eluted. In recent years, use has been regulated from the viewpoint of preventing marine pollution and river pollution.

As the method 5, epoxy resin or polyester resin is used as a paint, but it is difficult to combine acid resistance and alkali resistance, and when it is painted on iron or concrete, pinholes and cracks are generated. There was a defect that caused the coating to swell and peel off due to these causes.
Furthermore, when lining (coating) is used on the inner surface of the sedimentation tank, FRP (fiber reinforced plastic) and sheet lining are known, but workability and adhesive strength are high in high temperature and high humidity environments and concrete structures with high water content. However, the construction cost is expensive, so there is a problem in economic efficiency.

Recently, a method of coating a surface of a concrete structure with a disinfectant in which a fluororesin, copper, titanium, nickel powder and uncured cement or mortar are dispersed in water has appeared, as in Japanese Patent No. 280887. However, this method is suspected to be used as a carcinogenic metal and the use of this method is discouraged. In addition, copper is ionized too early in the compounded copper. There is a problem that the bactericidal effect is short.

The present invention solves the above-mentioned problems, and when applied to iron and concrete structures, it has good adhesion over a long period of time, and is sufficient for preventing deterioration even in an oxidizing environment due to metabolic action of microorganisms, algae, crustaceans, However, the present invention provides an environmentally safe and economical antibacterial and anticorrosive agent and method for preventing deterioration.

The present invention has been made from such a viewpoint, and the invention of claim 1 is that at least a fluororesin, a copper complex, titanium, titanium oxide powder and uncured acid-resistant cement or mortar are dispersed in water. It is a sterilizing and anticorrosive agent for iron and concrete structures, and the invention of claim 2 is characterized in that the blending ratio of the fluororesin and the copper complex, titanium, titanium oxide powder is 1: 3 to 3: 1 by weight. The antibacterial and anticorrosive agent for iron and concrete structures according to claim 1, and the invention according to claim 3 is the antibacterial and anticorrosive agent for iron and concrete structures according to claim 1, further comprising a water repellent and a water-soluble polymer. It is an antibacterial and anticorrosive agent for iron and concrete structures formed by adding any of the above.

Furthermore, the invention of claim 4 is a method of coating a surface of an iron and concrete structure with a sterilizing and anticorrosive agent in which at least a fluororesin and a copper complex, titanium, titanium oxide powder and uncured acid-resistant cement or mortar are dispersed in water. The invention according to claim 5 is characterized in that the blending ratio of the fluororesin and the copper complex, titanium, and titanium oxide powder is 1: 3 by weight. The method for preventing deterioration of iron and concrete structures according to claim 4, wherein the ratio is 3: 1.
The invention of claim 6 is a hardened by coating the surface of iron and concrete structures with a bactericidal and anticorrosive agent comprising the antibacterial and anticorrosive agent of claim 4 or 5 added with a water repellent and a water-soluble polymer. A method for preventing deterioration of iron and concrete structures.

In the practice of the present invention, there is no particular limitation on the fluororesin used, but usually an emulsion with water can be easily used, and there is no danger of ignition and explosion. Further, the copper complex, titanium, and titanium oxide powder may be added individually or simultaneously. These powders having a particle size of 0.1 to 0.01 mm can be applied.

When coated on concrete structures, fluororesin forms a network bond in the above composition, and is most excellent in acid resistance, alkali resistance and water resistance, and these three components coexist in copper complex, titanium and titanium oxide powder. As a result, it was confirmed that since a strong sterilized coating film was formed, propagation of microorganisms and the like was suppressed, and there was no change in the oxidation state.
In particular, it is desirable that the blending ratio of the fluororesin and the copper complex, titanium, and titanium oxide powder is 1: 3 to 3: 1 by weight from the viewpoint of the coating work and the bactericidal and anticorrosive effect after curing.
In addition, by adding and blending a water repellent and a water-soluble polymer, the water resistance after curing can be further enhanced with respect to concrete.

Sand having a particle size of about 0.2 to 1.0 mm, which is a component of acid-resistant cement or mortar, is used, but fine stones and siliceous materials can also be applied.
The blending amount of the acid-resistant cement or mortar and various compounding agents is preferably 60 to 70 parts by weight with respect to 10 to 30 parts by weight of the fluororesin from the viewpoints of workability and curability of the coating film.

The use of water-dispersed paint as the fluororesin helps the water in which the fluororesin is dispersed to accelerate the curing of acid-resistant cement and disperse various compounding agents, but it also adds appropriate water before painting This makes it easy to create a uniform coating, and there is no risk of explosion or ignition, and the workability of painting is good.

From the above description, the present invention has a favorable synergistic effect of fluororesin and copper complex, titanium, titanium oxide powder and acid-resistant cement, and adheres firmly to the surface of iron and concrete structures and is included in the coating film. Sterilization by copper complex, titanium metal ions, and photocatalysis of titanium oxide reduce the proliferation of microorganisms such as sulfate-reducing bacteria in contaminated water tanks and waterways, and the adhesion of algae and crustaceans This reduces the acid groups produced by the metabolic action of organisms, thus protecting iron and concrete from oxidative degradation (neutralization) due to oxides.

Since the present invention has a composition constituted by the above composition, the fluororesin is firmly bonded to the concrete structure by curing the fluororesin and the acid-resistant cement, and the fluororesin becomes a hardly soluble network-like water-resistant coating, and the acid-resistant cement Becomes an acid resistant film and forms a strong water and acid resistant film on the concrete surface.
In addition, the copper complex can stabilize the sterilization effect for a longer time by using a copper complex that is rapidly ionized and a copper complex that is slow in ionization, and the titanium powder gradually elutes from the coating film in water to produce metal ions, It reacts with sulfide ions generated in water to produce an insoluble metal oxide, so that it becomes a metal ion having a bactericidal action over a long period of time and sterilizes or inhibits living organisms.
Furthermore, the titanium oxide powder can sterilize microorganisms by photocatalysis and reduce the production of toxic sulfides.

In carrying out the present invention, 10 to 30 parts by weight of a fluororesin and 10 to 30 parts by weight of a copper complex, titanium, and titanium oxide powder are mixed and dispersed with water together with an acid-resistant cement or mortar material, and are coated and hardened on the concrete surface. . In this case, it is preferable that the fluororesin is dispersed in water as described above to form an emulsion.
The reason why the ratio of the fluororesin to the copper complex, titanium, and titanium oxide powder is 1: 3 to 3: 1 by weight as described above is that when the fluororesin is less than 1 part by weight, the copper complex, titanium, and titanium oxide powder are If the amount is more than 3 parts by weight, the metal powder in water will not be uniformly dispersed and the workability will be worse when coating on iron or concrete, and the coating will crack after the coating is cured and the adhesive performance will be impaired and will be practically used. The effect is small and the material cost is high, which is uneconomical.
Conversely, if the amount of fluororesin is more than 3 parts by weight and the amount of copper complex, titanium, or titanium oxide powder is less than 1 part by weight, the formation of metal-to-metal bonds is too small, and the amount of released metal ions is small, so the bactericidal effect Becomes insufficient, and the desired antibacterial and anticorrosive effect cannot be obtained.

The copper complex, titanium, and titanium oxide powders are not particularly limited in the proportion of each metal, but even if any of them is missing, the bactericidal and anticorrosive effects as intended in the present invention cannot be obtained.
If copper complex, titanium and titanium oxide powder are mixed in a predetermined blending amount, it is easy to obtain a coating film in which metal powder is uniformly dispersed, each metal is easily bonded at room temperature, and light and robust copper complex, A stable sterilizing and anticorrosive coating film can be obtained by constituting a titanium conjugate, further a copper complex and a titanium oxide conjugate.

The fluororesin is chemically stable, but after being cured and dried, voids of water that volatilized and escaped from the coating film are generated, and the water resistance is impaired. However, since the blended acid-resistant cement reacts with water and hardens, the voids can be filled, so that an acid-resistant water-resistant coating film in which the fluororesin and the acid-resistant cement are coordinated is obtained, and the anticorrosion function can be further enhanced. .

That is, in the composition according to the present invention, the use of copper complex, titanium, titanium oxide powder, these metals are easily ionized in water, so the ions of sulfide generated in water It becomes a metal oxide by reacting with, and it can prevent oxidative deterioration of concrete due to hydrogen sulfide generated by the metabolic action of anaerobic sulfate-reducing bacteria, and can also prevent adhesion of algae and crustaceans.

Furthermore, a sterilizing paint containing silver, copper, cuprous oxide, tin or the like used as a conventional sterilizing agent cannot provide a sufficient effect, and copper used as a sterilizing agent in Japanese Patent No. 280887. Since the ionization was fast and had a problem with sustainability, the effectiveness of the bactericidal effect was improved by using a copper complex with a fast ionization and a copper complex with a slow ionization instead of copper. In addition, it is significantly different from the fact that nickel, which is a suspected carcinogen, is replaced with the safe bactericidal effect of the photocatalytic action of titanium oxide, and the cement or mortar is replaced with acid-resistant cement.

Copper complex, titanium, titanium oxide powder (6: 1.5: 2.5) 20 parts Fluororesin 15 parts Add the appropriate amount of water to make an emulsion composition. A total of 65 parts by weight was added together with an appropriate amount of water to obtain the composition of the present invention, which was coated on the concrete surface.

Copper complex, Titanium, Titanium oxide powder (5: 1.5: 3.5) 15 parts Fluororesin 15 parts Add the appropriate amount of water to make an emulsion composition. A total of 70 parts by weight of a silane-based water repellent was added together with an appropriate amount of water to obtain a composition of the present invention, which was painted on the concrete surface.

Copper complex, Titanium, Titanium oxide powder (5: 1: 5) 10 parts Fluoro resin 15 parts Add appropriate amount of water to make emulsion composition, acid-resistant cement, cinnabar sand, styrene water-soluble A total of 75 parts by weight of the polymer was added together with an appropriate amount of water to obtain the composition of the present invention, which was coated on the concrete surface.
In order to compare with the sample of the present invention described above, a sample of a comparative example was made with the following formulation.

(Comparative Example 1)
Copper, titanium, nickel powder (5: 2.5: 2.5) 10 parts Fluororesin 15 parts Add the appropriate amount of water to make an emulsion composition, and add cement and cinnabar sand to it. 55 parts by weight were added together with an appropriate amount of water to obtain a composition of a comparative example (Japanese Patent No. 280887), which was coated on the concrete surface.

(Comparative Example 2)
Cuprous oxide 10 parts Green blue 5 parts Copper powder 10 parts Epoxy resin 25 parts Add appropriate amount of water to form an emulsion composition, and add cement and dredged sand to this to make 50 parts by weight of appropriate amount of water. And a composition of Comparative Example (Japanese Patent No. 2543794) was obtained, and this was coated on the concrete surface.

(Comparative Example 3)
Cuprous oxide 20 parts Polyester resin 15 parts The above materials were added to a suitable amount of solvent to form a comparative polyester paint, which was applied to the concrete surface.

(Comparative Example 4)
A concrete block on which nothing was painted was used as a sample for comparison.
Each composition shown in the above examples and comparative examples was coated on a concrete block to a thickness of 1 mm, and after curing, immersed in an aeration tank of a sewage treatment facility for 48 months and in a final sedimentation tank for 18 months. The adhesion of microorganisms and algae and the oxidation (neutralization state) of the concrete block were observed.
The results are as shown in the following Table 1 aeration tank and Table 2 final sedimentation tank.
The measurement was carried out by the following test method.
1. Evaluation of coating film appearance: It was performed with the naked eye and finger touch.
2. Microbe adhesion status: Observation by visual evaluation and observation by electron microscope.
3. Evaluation of adhesion and removal of algae: Evaluation of difficulty of removing algae by observation with the naked eye and washing with water.
4). Oxidation (neutralization) situation: Samples were rounded and measured by X-ray diffraction analysis and differential thermal analysis.

The present invention is used for water treatment facilities such as water and sewage systems, agricultural waterways, fish farm water tanks, power plant and factory water intakes, drainage channels and water tanks, food factories, etc., and by propagation of microorganisms such as iron and concrete structures. Used in industries that prevent oxidative deterioration (neutralization) and adhesion of algae and crustaceans.

Claims (6)

An antibacterial and anticorrosive agent for iron and concrete structures, wherein at least a fluororesin, a copper complex, titanium, titanium oxide powder and an uncured acid-resistant cement or mortar are dispersed in water. The antibacterial and anticorrosive agent for iron and concrete structures according to claim 1, wherein the blending ratio of the fluororesin and the copper complex, titanium, and titanium oxide powder is 1: 3 to 3: 1 by weight. The antibacterial and anticorrosive agent for iron and concrete structures according to claim 1 or 2, further comprising a water repellent or a water-soluble polymer as a sterilizing and anticorrosive agent. At least fluororesin and copper complex, titanium, titanium oxide powder and uncured acid-resistant cement or mortar dispersed in water is coated with a sterilizing and anticorrosive agent on the surface of iron and concrete structure and cured, Methods for preventing deterioration of iron and concrete structures. The antibacterial and anticorrosive agent for iron and concrete structures according to claim 4, wherein the blending ratio of the fluororesin and the copper complex, titanium and titanium oxide powder is 1: 3 to 3: 1 by weight. A method for preventing deterioration of iron and concrete structures, characterized in that the surface is painted and cured. As an antibacterial and anticorrosive agent, an antibacterial and anticorrosive agent for iron and concrete structures, which is a combination of a water repellent and a water-soluble polymer, is applied to the surface of the iron and concrete structures and cured. The method for preventing deterioration of iron and concrete structures according to claim 4 or 5, characterized by the above.