KR20080095526A - Water treating composition having function of microorganism sterilization and water treating method using the same - Google Patents

Abstract

A water treatment composite is provided to be conveniently used, have a bactericidal effect about all kinds of microorganism in the wide range water quality, to suppress etch reaction which is generated in a surface of metal and to effectively control the microorganism by suppressing scales of bivalence metal salt. A water treatment composite contains (a) 0.1 - 20 weight% of 1- sodium oxide -2- pyridinethiol (sodium 2-pyridinethiol-1-oxide), (b) 0.1 - 5 weight% of organic phosphate compound, (c) 0.1 - 5 weight% of azole compound , (d) 0.1 - 3 weight% of hydroxide and (e) water. The organic phosphate compound is selected from hydroxy ethylidine diphosphonic acid, tetra sodium hydroxy ethylidine bis phosphonic acid, hydroxy phosphono carboxylic acid, amino trimethylene phosphonic acid, phosphonobutane tricarboxylic acid and ethylenediamine tetramethylridine phosphonic acid.

Description

Water treating composition having function of microorganism sterilization and water treating method using the same}

The present invention relates to a water treatment composition having a microbial sterilization function, and more particularly, has a bactericidal effect on various microorganisms including algae (moss) that may occur in an open recirculating cooling system, and corrosion of metals. The present invention relates to a water treatment composition having an inhibitory effect and an inhibitory effect on the scaling of water ions and a water treatment method using the same.

The system using the cooling tower is called an open circulation cooling system because air continuously flows into the cooling tower. In the process of reusing water, the concentration of various ions and minerals contained in the water occurs due to the evaporation of water. Therefore, the water quality varies greatly depending on the method of treating the water used.

Major industrial facilities at the national base, such as petrochemicals, refineries, textiles, steel, electronics, and power plants, use open circulation cooling systems to cool the heat generated during the production process. However, because the open circulation cooling system is a very good environment for algae and other microorganisms to breed, you should always worry about contamination by microorganisms.

The material constituting the open circulation cooling system is mostly metal. In order to obtain a metallic material, energy is applied to the metal in an oxide state. The application of energy is an artificial force, but the emission of energy is a natural force. Corrosion is an extremely normal natural phenomena that attempts to dissipate energy and return metal to its natural state of oxide. Therefore, in the open circulation cooling system, corrosion of the metal material occurs.

In addition, scales are formed when deposits due to corrosion on metal surfaces or various metal cations present in the water are combined with anionic materials and the like. When the scale is attached, it forms a porous precipitate on the heat transfer surface of the heat exchanger, and thus prevents the smooth flow of water or, in severe cases, blocks the water pipe, and in some cases, due to the difference in the concentration of dissolved oxygen in the water It may also cause corrosion.

In various industrial installations that use water pipes, such as heat exchangers in open-circulation cooling systems installed at industrial sites, microbial contamination, corrosion and scale problems can be easily found. These problems not only impair the circulation cooling system. It causes serious economic loss due to shortening of lifespan, environmental pollution, human toxicity and thermal efficiency. In order to solve the above problems, the use of a coolant treatment agent is indispensable, and is currently widely used in the general industrial field.

In the case of using water treatment agents for treating the conventional cooling water, since the corrosion inhibitor, the scale inhibitor and the microorganism inhibitor are separately added and treated, one product input can solve all the problems of microbial contamination, corrosion and scale generation including algae (moss). There was no. Conventional water treatment compositions are known for their purpose in terms of corrosion and scale protection and microbial protection, respectively. For example, US Pat. No. 4,134,959 describes water treatment compositions using azole compounds and phosphates, while US Pat. No. 4,149,969 contains zinc salts, molybdates, manganese salts, nickel salts, azole compounds, and phosphonates. One composition, US Pat. No. 4,497,713, discloses a composition of zinc salts, cellulose gums, phosphonates, US Pat. No. 4,411,865 describes techniques using zinc salts, chromium salts, phosphates, acrylate copolymers, US Pat. No. 5,227,133 Cooling water treatment technology by the composition of zinc salts, molybdates, phosphates, US Patent No. 4,673,509 discloses a microbial treatment technology using tetrakis hydroxyl methyl phosphonium sulphate.

However, the conventional water treatment techniques have not been able to expect satisfactory performance with one composition in the ability to suppress microbial contamination, corrosion and scale, and corrosion and scale problems can be solved using chromium salts. Its use is regulated due to various problems such as human toxicity and stability.

Accordingly, an object of the present invention is to provide an easy-to-use water treatment composition in an open circulation cooling system while solving the existing problem of not treating microorganisms, corrosion and scale with one drug.

Still another object of the present invention is to provide a method of treating water using the water treatment composition.

In order to achieve the above object, the present invention is (a) 0.1 to 20% by weight of sodium 2-pyridinethiol-1-oxide, (b) phosphorus (P) content of the organic phosphate compound To 0.1 to 5% by weight, (c) 0.1 to 10% by weight of the azole compound, (d) 0.1 to 3% by weight of hydroxide, and (e) the remaining water.

The present invention also provides a water treatment method in which the water treatment composition is added to the water quality at a concentration of 0.1 to 500,000 ppm to sterilize microorganisms and suppress metal corrosion and scale formation.

Hereinafter, the present invention will be described in more detail.

In the water treatment composition according to the present invention, the content of (a) 1-sodium oxide-2-pyridinethiol is 0.1 to 20% by weight. If the content of 1-sodium oxide-2 pyridinethiol is less than 0.1% by weight, the bactericidal effect against microorganisms including algae (moss) is insufficient. If it contains more than 20% by weight, sediment may occur in the preparation of water treatment agent and it is not economical. .

In the present invention (b) as an organic phosphate compound used to maintain the concentration of phosphorus (P), hydroxyethylidene diphosphonic acid, tetrasodium hydroxyethylidine bisphosphonic acid, hydroxy Preference is given to using hydroxyl phosphono carboxylic acid, aminotrimethylene phosphonic acid, phosphonobutane tricarboxylic acid, ethylenediamine tetramethylidine phosphonic acid or mixtures thereof. The use amount of the organic phosphate compound is 0.1 to 5% by weight based on the phosphorus (P) content, where the phosphorus content is less than 0.1% by weight is insufficient for corrosion and scale prevention effect, when the phosphorus content exceeds 5% by weight of the water treatment agent Precipitation can occur in manufacturing and is not economical.

As the azole compound (c), it is preferable to use tolyltriazole, mercapto benzothiazole, benzotriazole, imidazole or a mixture thereof. The content of the azole compound is 0.1 to 10% by weight, the content of the azole compound is less than 0.1% by weight of the anticorrosive effect of the copper and copper compounds are insignificant, if it exceeds 10% by weight is not economical.

As the hydroxide (d), it is preferable to use sodium hydroxide, potassium hydroxide or a mixture thereof. The content of the hydroxide is 0.1 to 3% by weight, it is not preferable because the content may be out of the preferred pH range of 8 to 11 of the water treatment composition.

As described above, the water treatment composition of the present invention is preferably used after dilution and input to a water quality to be treated at a concentration of 0.1 to 500,000 ppm. The water treatment composition is effective in preventing various microbial contamination including algae (moss) that may occur in various industrial water pipes such as cooling towers, heat exchangers, and inhibiting corrosion and scale formation, and in particular, microorganisms including algae (moss) It is preferable to use it as a water treatment agent in an open circulation cooling system with serious problems.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The following examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by these examples. The characteristics of the test water quality used in Test Examples 1 and 2 are as shown in Table 1 below.

In Table 1, the pH was adjusted to 0.1N aqueous sodium hydroxide solution and 0.05N sulfuric acid aqueous solution, calcium hardness (Ca-H) was adjusted to calcium chloride, methyl orange-alkalinity (M-Alkalinity) was adjusted to sodium bicarbonate. In addition, magnesium hardness (Mg-H) was adjusted to magnesium sulfate, Chloride (Chloride) was used for the concentration of chlorine ions due to the calcium chloride used to control the calcium hardness, the deficiency was adjusted using sodium chloride.

Examples 1 to 5 Preparation of Water Treatment Composition

The water treatment compositions were each prepared in compositions as shown in Table 2 below.

In Table 2, tetrasodium hydroxyethylidine bisphosphonic acid is used as the organic phosphate compound, and is expressed based on phosphorus (P) content, and benzotriazole is used as the azole compound. In addition, each of the organic phosphate compound and the azole compound is added to the composition after preliminarily setting a stable pH range using caustic soda (hydroxide) in order to secure a stable pH range of 1-sodium oxide-2-pyritindiol. In order to improve the solubility, water was added first. The prepared composition was previously diluted to 10,000 ppm in order to apply at a concentration of 100 ppm in the following test example.

[Comparative Examples 1 to 4] Preparation of Water Treatment Composition

Each water treatment composition was prepared with a composition as shown in Table 3 below.

In Table 3, the same compounds as used in the examples were used as the components. The prepared composition was previously diluted to 10,000 ppm in order to apply at a concentration of 100 ppm in the following test example.

Test Example 1 Corrosion Prevention Performance Test

The water treatment composition (Examples 1 to 5, Comparative Examples 1 to 4) was maintained at 100 ppm in the test water quality (# 1 to # 4), respectively, and the carbon steel test piece (0.218dm ² ) at 30 ° C was rotated at 170 rpm. The corrosion rate [mdd: mg / (dm ² · day)] was measured by rotating for 5 days, and the results are shown in Table 4 below.

In Table 4, when the water treatment compositions of Examples 1 to 5 according to the present invention are used, the corrosion rate of the carbon steel is significantly lowered compared to the case of using the water treatment compositions of Comparative Examples 1 to 4, and the corrosion prevention effect is excellent. Can be.

Test Example 2 Scale Prevention Performance Test

The water treatment compositions (Examples 1 to 5 and Comparative Examples 1 to 4) were maintained in test water quality (# 1 to # 4) at a concentration of 100 ppm, respectively, and the test solution was sealed and held at 70 ° C. for 24 hours. After filtering the test solution with a 0.45 micro filter, the total hardness was measured, and the scale inhibition rate was measured using Equation 1 below, and the results are shown in Table 5 below.

[Equation 1]

% Inhibition = (Ce) / (Ct) 100

In Equation 1, Ce is the total hardness in the test solution before the test, Ct is the total hardness in the test solution after the test.

Looking at the Table 5, it can be seen that when using the water treatment compositions of Examples 1 to 5 according to the present invention, the scale inhibition rate is significantly improved compared to the case of using the water treatment compositions of Comparative Examples 1 to 4.

Test Example 3 MIC (Minimum Inhibitory Concentration) test for bacteria

The water treatment composition (Examples 1 to 5, Comparative Examples 1 to 4) was diluted according to the 2-fold serial dilution method using a 24 well plate, and then bacteria were inoculated at a concentration of 10 ⁴ CFU / ml. Then, incubated for 48 hours at 30 ℃, the MIC value was measured by visually determining the growth of bacteria based on turbidity, the results are shown in Table 6 below. At this time, the culture medium was observed turbidity using Dipco's Tryptic soy broth (DIFCO Co.), bacteria are Micrococcus leteus ATCC 9341, Staphylococcus aureus ( Staphylococcus aureus ATCC 6538) was used, and the basic diluent was distilled water.

Looking at Table 6, it can be seen that when the water treatment compositions of Examples 1 to 5 according to the present invention are used, the bactericidal efficacy against bacteria is significantly superior to that of the water treatment compositions of Comparative Examples 1 and 3 to 4.

Test Example 4 MIC Test for Algae

The water treatment composition (Examples 1 to 5, Comparative Examples 1 to 4) was diluted according to a 2-fold serial dilution method using a 24-well well plate, and then inoculated with algae at a concentration of 0.3 mg / liter of chlorophyll. After inoculation, the culture was incubated at a temperature of 30 ° C. for 10 days at 16 L: 8D, and then the MIC value was measured by visually determining the growth of algae based on color (green). Table 7 Shown in At this time, C-Medium was used as a medium, algae was used Chlorella vulgaris NIES-227, and distilled water was used as a basic diluent.

Looking at Table 7, it can be seen that when the water treatment compositions of Examples 1 to 5 according to the present invention are used, the sterilization effect against algae is remarkably excellent compared to the case of using the water treatment compositions of Comparative Examples 1 and 3 to 4.

As described above, the water treatment composition according to the present invention is easy to use, has a bactericidal effect against various microorganisms including algae in a wide range of water quality, can suppress corrosion reactions that may occur on metal surfaces, and divalent metal salts. Since the ability to suppress the scale of the excellent, there is an advantage that can effectively control the microorganism, corrosion and scale at the same time.

Claims (6)

(a) 0.1 to 20% by weight of 1-sodium 2-pyridinethiol-1-oxide, (b) organic phosphoric acid compound, 0.1 to 5% by weight based on phosphorus (P) content, (c) 0.1 to 10% by weight of an azole compound, (d) 0.1 to 3% by weight of hydroxide, and (e) A water treatment composition consisting of the remaining water. The method of claim 1, wherein the organic phosphate compound is hydroxyethylidine diphosphonic acid, tetrasodium hydroxyethylidine bisphosphonic acid, hydroxyphosphono carboxylic acid, aminotrimethylene phosphonic acid, phosphonobutane The water treatment composition which is at least one selected from the group consisting of tricarboxylic acid and ethylenediamine tetramethylidine phosphonic acid. The water treatment composition of claim 1, wherein the azole compound is at least one selected from the group consisting of tolyltriazole, mercapto benzothiazole, benzotriazole, and imidazole. The water treatment composition of claim 1, wherein the hydroxide is sodium hydroxide, potassium hydroxide or a mixture thereof. The water treatment method of claim 1, wherein the water treatment composition of claim 1 in a concentration of 0.1 to 500,000 ppm in water quality to sterilize microorganisms and inhibit metal corrosion and scale formation. The water treatment method according to claim 5, wherein the water treatment composition is introduced into a cooling tower and / or a heat exchanger.