KR20020011541A - Multifunctional Water-treating Composition and Method of water-treating using the same - Google Patents

Abstract

PURPOSE: Multifunctional water treating composition and method of water-treating using the same are provided to prevent corrosion, scale formation, and bacteria growth in a cooling system. CONSTITUTION: The composition is composed of bacteria restrainer of 0.05-15 wt.%, scale restrainer of 0.5-50 wt.%, organic phosphonate of 0.2-30 wt.% based on organic phosphonate ion, orthophosphate or zinc salt of 0.1-30 wt.% based on orthophosphate or zinc salt ion, nitrate of 0.02-20 wt.%.

Description

Multifunctional Water-treating Composition and Method of water-treating using the same

The present invention relates to a multifunctional water treatment agent composition and a water treatment method using the same, and more particularly, to inhibit corrosion, scale and microbial growth that may occur in an open circulation cooling system using water at the same time, as well as to store products or The present invention relates to a water treatment composition having excellent stability even in use.

In open circulation cooling systems, a cooling tower is used to control the temperature of the cooling water. The water temperature control system using the cooling tower is called an open circulation cooling system because air is always introduced.In the process of reusing the cooling water, various minerals contained in the water are concentrated due to evaporation of the water, and the cooling effect is affected by the treatment method of the water used. Various phenomena occur. These various phenomena can be classified into problems caused by corrosion, scale, and microorganisms.

Corrosion can be described simply as rust in metal materials. In general, metal is a material made by the process of refining what existed in the oxide state, and has a very strong property to return to the thermodynamically stable oxide state. Therefore, it is no wonder that corrosion occurs in open circulation cooling systems.

The scale is produced by combining various divalent metal ions present in the sediment due to corrosion on the surface of the metal or water with anionic chemicals.The solubility of metal salts decreases as the temperature of the cooling water rises. Scale loads easily occur at high temperatures due to heat loads such as refrigerators and heat exchangers. If the scale is too high, the pipe will be clogged and the heat transfer efficiency will be lowered to waste more energy than necessary.

Microorganisms such as bacteria, fungi and moss may or may not live well depending on the environment. Unfortunately, the temperature, pH, dissolved oxygen, minerals, sunlight, and other environmental conditions in the cooling tower are too good for microbes to live in. If microorganisms grow in such an environment and are entangled with each other and attached to the filling material of the cooling tower, the flow of water and air will be disturbed and cooling efficiency will be reduced. The lump of microorganisms attached to the cooling tower filling is called slime, and when the slime adheres to the surface of the metal pipe, local corrosion such as corrosion or lower corrosion by microorganisms may occur.

It can be found that corrosion, scale and slime occur very easily in various industrial facilities using water pipes, including heat exchangers of cooling air conditioning installed in actual industrial sites. In this case, the life cycle of cooling circulation system is reduced, heat transfer efficiency is reduced, It causes serious problems such as infection, environmental pollution and so on, resulting in huge economic loss.

In order to overcome this problem, various water treatment agents have been developed in the past, but conventional water treatment agent programs are used to separately treat corrosion inhibitors, scale inhibitors, and microbial inhibitors to perform water treatment. It is impossible to solve all the problems related to microbial growth. For example, a method has been generally used in which water treatment is performed by first introducing a scale inhibitor to inhibit scale formation in the cooling water and then adding a microbial inhibitor. As an example of a water treatment agent having such individual efficacy, US Pat. No. 4,134,959 describes a water treatment agent composition using an azole compound and phosphate. A technique is disclosed, and US Pat. No. 5,156,665 discloses an antimicrobial treatment technique.

However, the microbial protection function is weak in the water treatment agent composition with corrosion and scale prevention function, and the use of the water treatment agent is limited because the antimicrobial composition cannot be expected in the microbial protection composition. There was a management problem such as proper input. As such, corrosion inhibitors, scale inhibitors, and microbial inhibitors have been developed separately, and when they are mixed into one product, the stability of the product is lowered, such as lack of compatibility with each other, resulting in precipitation. It is because the effect which a compound has cannot be exhibited smoothly.

As a result of years of research to solve these problems, the inventors have developed a water treatment composition which is excellent in product stability in storage and use, and simultaneously solves problems related to corrosion, scale and microbial growth in an open circulation cooling system. Accordingly, it is an object of the present invention to provide a cooling tower water treatment composition and a water treatment method using the same, which are easier to use because they suppress corrosion, scale and microbial generation problems, unlike conventional water treatment agents. It is another object of the present invention to provide a water treatment composition and a water treatment method using the same having excellent compatibility between component compounds and excellent stability in storage and use of a product.

In order to achieve this object, the present invention provides a multifunctional water treatment composition comprising a microbial growth inhibitor, an anti-scale formation agent, an organic phosphonate, a nitrate, and a phosphate salt and / or zinc salt. Here, 3-isothiazolinone is used as the microbial growth inhibitor, and an acrylate polymer is preferably used as the scale formation inhibitor. In addition, the content of the microorganism growth inhibitor in the water treatment agent composition is 0.05 to 15% by weight, the content of the anti-scale agent is 0.5 to 50% by weight, the content of the organic phosphonate is 0.2 to 30% by weight based on the organic phosphonate ion %, The content of the phosphate and / or zinc salt is 0.1 to 30% by weight based on the total amount of phosphate and zinc ions, the content of the nitrate is preferably 0.02 to 20% by weight based on nitrate ions.

The invention also includes the process of administering a multifunctional water treatment composition comprising a microbial growth inhibitor, an anti-scale formation agent, an organic phosphonate, a nitrate, and a phosphate salt and / or a zinc salt to a cooling water system. It also provides a water treatment method such as suppression.

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

Microorganism growth inhibitors used in the water treatment agent composition of the present invention can be widely used microorganism growth inhibitors, but using the 3-isothiazolinone of the general formula (1), organic anti-scaling agent It is preferable because it has excellent compatibility with other components such as nate, phosphate or zinc salt, has an inhibitory effect on a wide range of microorganisms, and has excellent sustainability.

(In Formula 1, R is hydrogen or chlorine.)

Specifically, 2-methyl-4-isothiazolone-3-one in which R ₀ group is hydrogen in Formula 1 or 5-chloro-2-methyl-4-isothiazolone-3-one in which R ₀ group is chlorine is used. More preferably, 2-methyl-4-isothiazolone-3-one and 5-chloro-2-methyl-4-isothiazolone-3-one are mixed in a weight ratio of 1:20 to 20: 1 It is especially preferable to use what exists. The content of 3-isothiazolinone of Chemical Formula 1 in the water treatment agent composition of the present invention is preferably 0.05 to 15% by weight relative to the total composition, and when the content of 3-isothiazolinone is less than 0.05% by weight, the bactericidal effect is lowered. If it contains more than 15% by weight, the sterilization effect is good but economical.

As the scale formation inhibitor used in the water treatment agent composition of the present invention, a known scale formation inhibitor may be widely used. However, when the acrylate polymer of Formula 2 is used, microorganism growth inhibitor, organic phosphonate, orthophosphate or It is excellent in compatibility with zinc salts and the like, and is particularly excellent in scaling inhibitory effect of divalent metal salts.

In Formula 2, l, m, and n are the same as or different from each other, and each is an integer of 0 to 1000, R is hydrogen, methyl, or a carboxyl group, and when R is a carboxyl group, an anhydrous ring is bonded to an adjacent carboxyl group. R ₁ and R ₈ may be the same as or different from each other, and represent hydrogen, an alkyl group, a hydroxy group, or a phosphono group, and R ₂ and R ₃ may be the same as or different from each other, or a hydrogen or C ₁ -C ₂ alkyl group. R ₄ represents hydrogen or an alkyl group of C ₁ -C ₅ , R ₅ represents an alkyl group of C ₁ -C ₈ or an alalkyl group of C ₈ -C ₁₀ , and X and Y are the same as or different from each other. hydrogen, represents a hydroxyalkyl group of C ₁ -C ₅ alkyl or C ₁ -C ₅ a. In addition, R ₀ in the formula includes one or more units selected from the following formula (3), (4), and (5).

In the formula, R ₆ and R ₁₂ are the same as or different from each other, and represent hydrogen or an alkyl group of C ₁ -C ₂ , and R ₁₃ and R ₁₄ are the same or different from each other, hydrogen, an alkyl group of C ₁ -C ₈ , and C ₆ of -C ₈ cycloalkyl group, benzyl group, or to indicate the units of formula (6), R ₇ represents a unit of the alkyl group of _{C 1 -C 6, C 6 -C} 10 alkyl group or al of the formula (6).

In Formula 6, i is 1, 2 or 3, R ₉ is hydrogen or an alkyl group of C ₁ -C ₂ , R ₁₀ represents hydrogen or an alkyl group of C ₁ -C ₆ .

The content of the acrylate-based polymer in the water treatment composition of the present invention is preferably 0.5 to 50% by weight, and if the content of the acrylate-based polymer is less than 0.5% by weight, the scale inhibiting ability is lowered and exceeds 50% by weight. Scale suppression effect is good but not economical.

The water treatment agent composition of the present invention further comprises orthophosphate and / or zinc salt in order to increase the compatibility and corrosion protection performance of each component, wherein the orthophosphate used in this case is the first phosphate, agent Diphosphate, tertiary phosphate, or phosphoric acid may be used alone or in combination. Particularly, phosphoric acid may be used, and zinc chloride, zinc sulfate, zinc nitrate, or the like may be used alone or in combination. The content of the phosphate salt and / or zinc salt in the total water treatment composition is preferably 0.1 to 30% by weight based on the total content of each ion (ie, the total content of the phosphate ions and zinc ions), more preferably zinc. It is preferable that the content of ions is in the range of 0.1 to 20% by weight, and the content of the phosphate ions is in the range of 0.5 to 30% by weight. If the content of zinc ions is less than 0.1% by weight, the corrosion protection is inadequate. If the content of zinc ions exceeds 20% by weight, there is a risk of adversely affecting the wastewater when discharging wastewater. Corrosion prevention effect is insignificant, and if it exceeds 30% by weight, there is a fear of causing calcium phosphate scale.

Organic phosphonates used in the present invention include hydroxy ethylidine diphosphonic acid, hydroxyphosphono carboxylic acid, aminotrimethylene phosphonic acid, phosphonobutane tricarboxylic acid, ethylene diamine tetra methylidine phospho Nickel acid and the like can be used, and the content of the organic phosphonate in the total water treatment composition is preferably 0.2 to 30% by weight based on the organic phosphonate ions. If the content of the organic phosphonate ion is less than 0.2% by weight, the corrosion and scale preventing effect is insufficient, and if it exceeds 30% by weight, it is not economical.

The nitrate used in the present invention not only commercializes microbial growth inhibitors, scale formation inhibitors, organic phosphonates and phosphates, but also plays a role in improving storage stability. Magnesium nitrate, copper nitrate, and the like can be used. The content of nitrate in the water treatment agent composition of the present invention is preferably 0.02 to 20% by weight based on nitrate ions. If the content of nitrate is less than 0.02% by weight, the anticorrosive effect and product storage stability effect are lowered and 20% by weight. If it exceeds, it is not economical.

The water treatment composition of the present invention is preferably used by diluting and dissolving at a concentration of 1 ppm to 500,000 ppm in water such as cooling water to be treated. Since the water treatment agent composition of the present invention can be used more effectively to prevent scale and suppress corrosion that may occur in various industrial water pipes including cooling towers and heat exchangers, open circulation cooling systems and transient cooling systems may be used. Among them, it is more preferable to use it as a water treatment agent in an open circulation cooling system having a high corrosion tendency and serious microbial problems.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited by the following Examples.

Example 1-6 and Comparative Example 1-4

Dissolve the water treatment composition in which the phosphate, zinc salt, acrylate copolymer, organic phosphonate, isothiazolinone, and nitrate were mixed in various test waters (Tables 3, 5, and 7). After the content of the ingredients is as described in Table 1 (Examples 1 to 6) and Table 2 (Comparative Examples 1 to 4), a corrosion inhibition test, a scale formation inhibition test and a microbial growth inhibition test were performed. Tables 4, 6 and 8 are shown respectively.

Content of each component in the water treatment program in which the composition of the present invention was dissolved (Examples 1-6) ingredient Content (ppm) Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Phosphate ions 8 6 4 0 0 0 Zinc ions 0 0 0 2 2.5 3 Acrylate polymer 5 7.5 10 5 7.5 10 Organic phosphonates 4 6 8 4 6 8 Isothiazolinone 1.5 2.0 2.5 1.5 2.0 2.5 Nitrate ions 2.5 4 6.5 2.5 4 6.5

The content of each component in the water treatment program in which the conventional water treatment composition is dissolved (Comparative Example 1-4) ingredient Content (ppm) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Phosphate ions 0 8 0 0 Zinc ions 0 0 0 2 Acrylate polymer 0 0 0 0 Organic phosphonates 0 0 2 0 Isothiazolinone 0 0.8 0 0.8 Nitrate ions 0 6.5 6.5 6.5

In Tables 1 and 2, the organic phosphonate represents hydroxyethylidine diphosphonic acid [HEDP (LONZA)], and the acrylate copolymer was used Belclene 400, a product of FMC, and isothiazolinone was SK. SKYBIO WG, a chemical product, was used. Phosphoric acid, zinc chloride and magnesium nitrate were used as salts for forming phosphate, zinc and nitrate ions, respectively.

end. Corrosion test

The corrosion test was carried out using a rotating corrosion tester. The corrosion rate of the carbon steel was measured by rotating the carbon steel test piece at a rotational speed of 170 rpm in an air injection state at a temperature of 30 ° C. and 10 CC / min. At this time, the concentration of the water treatment agent component of the present invention shown in Table 1 and the water treatment agent component of the comparative example shown in Table 2 was immersed for 5 days, and the corrosion rate according to the weight loss of carbon steel [mdd, mg / (dm ² · day)] was measured and shown in Table 4.

Test water quality used for corrosion test Water quality #One #2 # 3 PH 7.5-8.0 Calcium hardness (ppm) 100 200 300 M-Alkalido (ppm) 80 100 120 Total hardness (ppm) 120 240 360 Chlorine Ion (ppm) 80 160 240

The pH of the test water was adjusted to 0.1N sodium hydroxide solution and 0.05N sulfuric acid solution, calcium hardness was adjusted to calcium chloride, M-alkaline to sodium bicarbonate, magnesium hardness to magnesium sulfate, and chlorine ion content to sodium chloride, respectively. , Total hardness is the sum of calcium and magnesium hardness.

Corrosion test results of Example 1-6 and Comparative Example 1-4 Corrosion Result (mdd) Water Quality # 1 Water Quality # 2 Water Quality # 3 Example 1 4.86 6.35 7.53 Example 2 4.98 6.21 6.08 Example 3 5.96 7.52 7.43 Example 4 4.56 4.72 4.64 Example 5 3.86 4.08 4.21 Example 6 3.08 2.86 3.27 Comparative Example 1 312.39 212.29 167.06 Comparative Example 2 20.08 27.48 18.86 Comparative Example 3 35.36 45.03 67.94 Comparative Example 4 20.08 27.48 18.86

^{* Mdd = mg / (dm 2} · day)

As can be seen from Table 4, compared to the comparative example in which the phosphate, zinc salt or organic phosphonate alone is added, since the anti-corrosion effect of the compositions of Examples 1 to 6 is significantly superior, the present invention It is found that the multifunctional water treatment agent composition is stable even in a mixed state, and also has an excellent corrosion protection effect.

I. Scale Formation Suppression Test

The test solution was sealed and allowed to stand at 75 ° C. for 24 hours, filtered through a 0.45 micrometer filter, and the total hardness at this time was measured to determine scale inhibition. The test water quality was as shown in Table 5 below, and the test water quality was maintained and tested for each concentration of the water treatment agent component of the present invention shown in Table 1 and the water treatment agent component of the comparative example shown in Table 2, scaled by the following equation (1) The inhibition rate was calculated and the results are shown in Table 6.

[Equation 1]

In the above formula, Ct represents the total hardness in the test solution before the test, and Ce represents the total hardness in the test solution after the test.

Test water quality used for scale suppression test Water quality # One # 2 # 3 Calcium Hardness (ppm) 100 200 300 M-Alkaline (ppm) 100 200 300 Chlorine Ion (ppm) 80 160 240

In the test water quality of Table 5, calcium hardness was adjusted to calcium chloride, M- alkalinity was adjusted to sodium bicarbonate, chlorine ions to sodium chloride, respectively.

Scale inhibition test result of Example 1-6 and Comparative Example 1-4 Scale Suppression Ratio (%) Water Quality # 1 Water Quality # 2 Water Quality # 3 Example 1 98 98 95 Example 2 100 100 98 Example 3 100 100 100 Example 4 100 100 98 Example 5 100 100 100 Example 6 100 100 100 Comparative Example 1 90 63 33 Comparative Example 2 86 58 29 Comparative Example 3 93 78 67 Comparative Example 4 86 58 29

As can be seen from Table 6, the scale inhibition rate of Examples 1 to 6 according to the present invention is superior to that of Comparative Examples 1 to 4.

All. Microbial inhibition test

Temperature 30 ℃, 170rpm, 8 jong microorganisms from the air injection conditions of 10ml / min (Enterobacter aerogens ATCC 13048 , Escherichia coli ATCC 11229, Micrococcus luteus ATCC 9341, Pseudomonas aeruginosa ATCC 15442, Klebsiella pneumoniae ATCC 1560, Staphylococcus edidermis ATCC 155, Staphylococcus aureus A mixture solution of ATCC 6538, 8 kinds of Bacillus subtilis ATCC 6984) was injected to measure the decrease in the concentration of microorganisms after 2 days. At this time, the microbial mixture was prepared in 10 ⁶ CFU / ml and then the concentration of microorganisms in the test water of the following Table 7 to 10 ⁵ CFU / ml, and then the composition of Examples 1 to 3 and Table 2 shown in Table 1 After maintaining the composition of Comparative Examples 1-3 indicated at each concentration, the amount of microbial inhibition was tested and the results are shown in Table 8.

Test water quality used for microbial growth inhibition test Water quality #One #2 # 3 pH 7.5-8.0 Calcium hardness (ppm) 100 200 300 M-Alkalido (ppm) 80 100 120 Total hardness (ppm) 120 240 360 Chlorine Ion (ppm) 80 160 240 Initial Microbial Count (CFU / ml) 10 ⁵ 10 ⁵ 10 ⁵

Microbial growth inhibition test results of Example 1-6 and Comparative Example 1-4 Microbial water (CFU / ml) Water Quality # 1 Water Quality # 2 Water Quality # 3 Example 1 10 ¹ 10 ² 10 ² Example 2 0 10 ¹ 10 ¹ Example 3 0 0 0 Example 4 10 ¹ 10 ² 10 ² Example 5 0 10 ¹ 10 ¹ Example 6 0 0 0 Comparative Example 1 10 ⁷ 10 ⁸ 10 ⁸ Comparative Example 2 10 ³ 10 ⁴ 10 ⁴ Comparative Example 3 10 ⁷ 10 ⁸ 10 ⁸ Comparative Example 4 10 ³ 10 ⁴ 10 ⁴

* CFU / ml = Colony Forming Unit / ml

As can be seen from Table 8, in the case of using the water treatment composition of Examples 1 to 6 according to the present invention, microbial growth inhibitors are used alone or in combination with other materials. Since the suppression rate is extremely high, it turns out that it is stable also in the state in which the multifunctional water treatment composition of this invention is mixed, and the microbial inhibitory effect also raises.

Taken together, these test results show that the water treatment agent composition for open circulation cooling system according to the present invention synergistically improves the corrosion prevention function, the scale generation prevention function and the microbial sterilization effect of the metal, and has excellent use and storage stability. there was.

The water treatment composition of the present invention has a sustained sterilizing power, has excellent sterilization effect against all microorganisms in an open circulation cooling system in which concentration occurs, and has a function of preventing both anodization and cathodic reactions during corrosion reactions. Excellent corrosion protection can be expected by minimizing possible corrosion conditions. In addition, since the acrylate copolymer and the organic phosphonate convert the crystal structure of the divalent metal salt scale to suppress scale formation, problems related to corrosion, scale, and microorganisms can be synergistically solved at the same time.

Claims (11)

A multifunctional water treatment composition comprising a microbial growth inhibitor, an anti-scale formation agent, an organic phosphonate, a nitrate, and a phosphate and / or zinc salt. The multifunctional water treatment composition according to claim 1, wherein the microbial growth inhibitor is 3-isothiazolinone and the scale forming agent is an acrylate polymer. The multifunctional water treatment composition according to claim 2, wherein the 3-isothiazolinone is a compound represented by the following Chemical Formula 1, and the acrylate polymer is a polymer represented by the following Chemical Formula 2. [Formula 1] [Formula 2] In Formula 2, l, m, and n are the same as or different from each other, and each is an integer of 0 to 1000, R is hydrogen, methyl, or a carboxyl group, and when R is a carboxyl group, an anhydrous ring is bonded to an adjacent carboxyl group. R ₁ and R ₈ may be the same as or different from each other, and represent hydrogen, an alkyl group, a hydroxy group, or a phosphono group, and R ₂ and R ₃ may be the same as or different from each other, or a hydrogen or C ₁ -C ₂ alkyl group. R ₄ represents hydrogen or an alkyl group of C ₁ -C ₅ , R ₅ represents an alkyl group of C ₁ -C ₈ or an alalkyl group of C ₈ -C ₁₀ , and X and Y are the same as or different from each other. hydrogen, represents a hydroxyalkyl group of C ₁ -C ₅ alkyl or C ₁ -C ₅ a. In addition, R ₀ in the formula includes one or more units selected from the following formula (3), (4), and (5). [Formula 3] [Formula 4] [Formula 5] In the formula, R ₆ and R ₁₂ are the same as or different from each other, and represent hydrogen or an alkyl group of C ₁ -C ₂ , and R ₁₃ and R ₁₄ are the same or different from each other, hydrogen, an alkyl group of C ₁ -C ₈ , and C ₆ of -C ₈ cycloalkyl group, benzyl group, or to indicate the units of formula (6), R ₇ represents a unit of the alkyl group of _{C 1 -C 6, C 6 -C} 10 alkyl group or al of the formula (6). [Formula 6] In Formula 6, i is 1, 2 or 3, R ₉ is hydrogen or an alkyl group of C ₁ -C ₂ , R ₁₀ represents hydrogen or an alkyl group of C ₁ -C ₆ . The method of claim 3, wherein the 3-isothiazolinone has 2-methyl-4-isothiazolone-3-one and 5-chloro-2methyl-4-isothiazolone-3-one in a range of 1:20 to 20. A multifunctional water treatment composition, which is mixed at a weight ratio of 1: 1. The multifunctional water treatment composition according to claim 1, wherein the phosphate is phosphoric acid. The multifunctional water treatment composition according to claim 1, wherein the zinc salt is at least one compound selected from the group consisting of zinc chloride, zinc sulfate and zinc nitrate. The method of claim 1, wherein the organic phosphonate is hydroxy ethylidine diphosphonic acid, hydroxyphosphono carboxylic acid, aminotrimethylene phosphonic acid, phosphonobutane tricarboxylic acid and ethylenediamine tetra methylidine phosphate. A multifunctional water treatment composition, characterized in that at least one compound selected from the group consisting of phonic acid. The multifunctional water treatment composition according to claim 1, wherein the nitrate is at least one compound selected from the group consisting of magnesium nitrate and copper nitrate. According to claim 1, wherein the content of the microorganism growth inhibitor is 0.05 to 15% by weight, the content of the anti-scale agent is 0.5 to 50% by weight, the content of the organic phosphonate is 0.2 based on the organic phosphonate ion To 30% by weight, the phosphate and / or zinc salt content is 0.1 to 30% by weight based on the total amount of phosphate and zinc ions, the content of the nitrate is 0.02 to 20% by weight based on nitrate ions Multifunctional water treatment composition. A water treatment method comprising the step of introducing a multifunctional water treatment composition comprising a microbial growth inhibitor, an anti-scale formation agent, an organic phosphonate, a nitrate, and a phosphate salt and / or a zinc salt into a cooling water system. The water treatment method according to claim 10, wherein the water treatment composition is added to a cooling water system so that the concentration of the water treatment composition is from 1 ppm to 500,000 ppm.