KR20040012135A - Water treatmrnt composition, preparation method of the same and water treatment method using the same - Google Patents

Abstract

PURPOSE: A water treating agent composition which obtains superior metal corrosion and scale suppressing effects in water quality, and easily controls pH and is simply used in an open circulation cooling system is provided, a method for preparing the same is provided, and a water treating method using the same is provided. CONSTITUTION: The water treating agent composition comprises (a) 0.5 to 40 wt.% of phosphonate selected from the group consisting of hydroxy ethylidene diphosphonic acid, hydroxy phosphono carboxylic acid, amino trimethylene phosphonic acid, phosphono butane tricarboxylic acid and ethylene diamine tetramethylidene phosphonic acid; (b) 0.1 to 30 wt.% of acrylate polymer represented by formula I; (c) 0.1 to 10 wt.% of azole class compound selected from the group consisting of tolyltriazole, mercapto benzothiazole, benzotriazole and imidazole; (d) 0.1 to 20 wt.% of alcohol selected from the group consisting of methyl alcohol, ethyl alcohol and isopropyl alcohol; and (e) a balance of water. The method for preparing the water treating agent composition comprises the step of mixing a mixture of phosphonate, acrylate polymer and water with a mixture of azole class compound, alcohol and water in a weight ratio of 99:1 to 70:30. The water treating method comprises the process of suppressing metal corrosion and scale formation in water by injecting the water treating agent composition into cooling tower, heat exchanger and/or various drain pipes.

Description

WATER TREATMRNT COMPOSITION, PREPARATION METHOD OF THE SAME AND WATER TREATMENT METHOD USING THE SAME

[Industrial use]

The present invention relates to a water treatment composition, a method for preparing the same, and a water treatment method using the same. More particularly, the water treatment composition has an excellent effect of inhibiting metal corrosion and scale in water quality, and is easy to use and easily adjusts pH in an open circulation cooling system. It relates to a manufacturing method and a water treatment method using the same.

[Prior art]

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 process.

The material constituting the open circulation cooling system is mostly metal. In general, metals are made of a material to be used by applying energy to 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 phenomenon that releases energy and attempts to return the metal to its natural oxide state. Therefore, when a metal, which is an electrical conductor, comes into contact with an electrolyte material that is an ion conductor, corrosion occurs, which is a natural phenomenon of forming a positive electrode and a negative electrode due to a potential difference on a metal surface and returning to an oxide state.

On the other hand, when various metal ions present in the sediment due to corrosion on the surface of the metal or water are combined with the air or anionic chemicals, the scale is formed as an inorganic substance, and slime occurs when the microorganism forms a large colony.

When scale and slime are attached, porous deposits are formed on the heat transfer surface of the heat exchanger, which prevents the smooth flow of water or blocks the water pipe in severe cases, and in some cases, depending on the difference in the concentration of dissolved oxygen in the water It may also cause corrosion.

It can be found that corrosion, scale and microbial slime easily occur in various industrial facilities using water pipes, including heat exchangers of cooling air conditioning installed in actual industrial sites. It causes serious problems, causing huge economic losses.

In order to solve the above problems, the coolant treatment agent is indispensably used, and is currently widely used in all industrial fields.

In the case of a water treatment agent containing an azole compound which is widely used as a conventional cooling water treatment agent, the water treatment agent was kept alkaline using sodium hydroxide or potassium hydroxide to dissolve the azole compound. However, when the pH of the product is prepared alkaline like the conventional water treatment agent, the pH of the cooling water is maintained at 8.6 or higher when applied to a high concentration process or an open circulation cooling system having a high pH of the cooling water.

If the pH of the cooling water is more than 8.6, it exceeds the legal environmental regulation of the wastewater discharge standard 8.6.Therefore, there is a restriction on the use of water treatment agent, and since the carbonate content is relatively increased, the possibility of formation of calcium carbonate scale becomes very high. Satisfying environmental standards made it very difficult to solve corrosion or scale problems.

As a conventional water treatment composition, the technique using chromium salts was widely used in the 1960s, but the use of chromium salts is regulated because it causes environmental pollution by heavy metals and is highly toxic to the human body.

Recently, examples using phosphates, azole compounds, acrylic polymers, maleic polymers, lignin, tannins, etc. have been published and are widely used in industrial fields. For example, U.S. Patent No. 4,134,959 describes a water treatment agent composition using an azole compound and phosphate, and U.S. Patent No. 4,149,969 discloses zinc salts, molybdates, manganese salts, nickel salts, azole compounds, and phosphonates. Compositions containing zinc salts, cellulose gums, and phosphonates are disclosed, and US Patent Nos. 4,411,865 using zinc salts, chromium salts, phosphates, and acrylate copolymers. A technique has been reported, and in US Pat. No. 5,227,133, a cooling water treatment technique with a composition of zinc salt, molybdate and phosphate is reported.

However, the conventional water treatment composition is slightly different in the effect of preventing the corrosion or the ability to suppress the scale, but can not expect satisfactory performance, it is possible to solve the problem of corrosion and scale when using chromium salt, pollution pollution, human body The use is regulated due to various problems such as toxicity, stability, etc.

The present inventors have discovered a technology for preparing a water treatment agent that inhibits corrosion and scale generation even in a wide range of water quality by inducing complementary actions of compounds that have been used as conventional cooling water treatment agents.

Therefore, the present invention solves the problems of the existing water treatment agent lacking the pH control function and corrosion and scale generation in the open circulation cooling system using high pH cooling water or having a relatively high concentration, and having difficulty in pH management. The aim is to provide a water treatment agent that is easier to use.

The present invention is to solve the above-mentioned problems, an object of the present invention is to provide a water treatment agent composition excellent in metal corrosion and scale suppression effect in a wide range of water quality, easy to adjust pH and easy to use in an open circulation cooling system.

It is also an object of the present invention to provide a method for preparing the water treatment composition.

It is also an object of the present invention to provide a water treatment method using the water treatment composition.

In order to achieve the above object, the present invention (a) 0.5 to 40% by weight of phosphonate; (b) 0.1 to 30% by weight of acrylate polymer; (c) 0.1 to 10% by weight of an azole compound; (d) 0.1 to 20% by weight of alcohol; And (e) water balance.

The present invention also provides a process for preparing a water treatment composition comprising mixing a mixture of phosphonate, acrylate polymer and water with a mixture of azole compound, alcohol and water in a weight ratio of 99: 1 to 70:30. to provide.

The present invention also provides a water treatment method in which the water treatment agent composition is added to a cooling tower, a heat exchanger, and / or various drain pipes to suppress corrosion of metal and formation of scale in water.

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

The water treatment composition of the present invention comprises (a) phosphonate; (b) acrylate polymers; (c) azole compounds; (d) alcohols; And (e) water.

The (a) phosphonate in the water treatment composition of the present invention simultaneously inhibits the positive and negative electrode reactions during the corrosion reaction, and functions to suppress the scale of the divalent metal salt.

The content of the phosphonate (a) is preferably 0.5 to 40% by weight, more preferably 1.0 to 35% by weight based on the water treatment agent composition. If the content of the phosphonate in the water treatment composition is less than 0.5% by weight, the anti-corrosion ability and the anti-scaling function is lowered. If the content of the phosphonate is more than 40% by weight, the corrosion and scale suppression effect is excellent, but the economical efficiency in the preparation of the water treatment agent is improved and the overall performance is improved. This may indicate a problem with the product configuration.

As the (a) phosphonate, hydroxy ethylidine diphosphonic acid, hydroxy phosphono carboxylic acid, amino trimethylene phosphonic acid, phosphono butane tri carboxylic acid, ethylene diamine tetra methylidine phosphonic acid or these A mixture of may be preferably used.

In addition, the (b) acrylate polymer in the water treatment composition of the present invention functions to suppress the scale of the divalent metal salt.

The (b) acrylate polymer is preferably 0.1 to 30% by weight based on the water treatment composition. If the content of the phosphonate in the water treatment composition is less than 0.1% by weight, the scale inhibiting function of the divalent metal salt is insignificant. It is difficult to transport because of high.

As the acrylate polymer (b), an acrylate polymer of the following Chemical Formula 1 may be preferably used.

In Formula 1, l, m and n may be the same or different from each other, each independently represent an integer of 0 to 1,000, R is hydrogen, methyl or carboxyl group, when R is a carboxyl group is bonded to an adjacent carboxyl group anhydrous ring anhydrous ring), R ₁ and R ₈ may be the same or different from each other, and each independently hydrogen, an alkyl group, a hydroxy group or a phosphono group, and R ₂ and R ₃ may be the same or different from each other, Independently hydrogen or a C ₁ -C ₂ alkyl group, R ₄ is hydrogen or a C ₁ -C ₅ alkyl group, R ₅ is a C ₁ -C ₈ alkyl group or a C ₈ -C ₁₀ aralkyl group, and X and Y are each other the same or be different, and each independently hydrogen, hydroxy alkyl of C ₁ -C ₅ alkyl group or a C ₁ -C _5, R ₀ is selected from the group consisting of a compound represented by the following formula 2, 3 and 4 will be.

In Formulas 2 to 4, R ₆ and R ₁₂ may be the same or different from each other, each independently hydrogen or an alkyl group of C ₁ -C ₂ , R ₁₃ and R ₁₄ may be the same or different from each other, each independently Hydrogen, an alkyl group of C ₁ -C ₈ , a cycloalkyl group of C ₆ -C ₈ , a benzyl group or a compound of formula 5, R ₇ is an alkyl group of C ₁ -C ₆ , an allyl group of C ₆ -C ₁₀ , C An aralkyl group of ₆ -C ₁₀ or a compound of formula (5).

In Formula 5, i is 1, 2 or 3, R ₉ is hydrogen or an alkyl group of C ₁ -C ₂ , R ₁₀ is hydrogen or an alkyl group of C ₁ -C ₆ .

In addition, the (c) azole compound in the water treatment composition of the present invention is excellent in the corrosion inhibitory function of copper and copper compounds.

The content of the azole compound (c) is preferably 0.1 to 10% by weight, more preferably 0.2 to 8% by weight based on the water treatment agent composition. If the content of the azole compound in the water treatment composition is less than 0.1% by weight, the corrosion inhibitory function of the copper or copper compound is insignificant, and if it exceeds 10% by weight, the azole compound itself may precipitate and precipitate during long term storage. There is a problem that is not desirable and economical.

As the azole compound (c), tolyltriazole, mercapto benzothiazole, benzotriazole, imidazole or a mixture thereof may be preferably used.

In addition, the (d) alcohol in the water treatment composition of the present invention functions to improve the dissolution and storage stability of the azole compound.

The content of the alcohol (d) is preferably 0.1 to 20% by weight, more preferably 0.2 to 15% by weight based on the water treatment composition. If the content of the alcohol in the water treatment composition is less than 0.1% by weight, the dissolving function of the azole compound is insignificant, and if it exceeds 20% by weight, there is a problem of further increasing the COD concentration of the effluent of the open circulation cooling system.

As the alcohol (d), methyl alcohol, ethyl alcohol, isopropyl alcohol or a mixture thereof may be preferably used.

In addition, the water treatment composition of the present invention further comprises (e) water.

It is more preferable to use pure water or distilled water without ion as said (e) water.

The present invention also provides a water treatment agent composition comprising preparing a water treatment agent composition by mixing a mixture of phosphonate, acrylate polymer and water with a mixture of an azole compound, alcohol and water in a weight ratio of 99: 1 to 70:30. Provide a method.

In the method for preparing the water treatment composition, when the weight of the mixture of the phosphonate, the acrylate polymer and the water exceeds 99g with respect to 1g of the mixture of the azole compound, the alcohol and the water, the corrosion preventing ability and the anti-scaling function are insignificant, and the divalent There is a problem that the scale inhibiting function of the metal is insignificant, and if the weight of the mixture of the phosphonate, the acrylate polymer and the water is less than 70 g with respect to 30 g of the mixture of the azole compound, the alcohol and the water, the corrosion inhibition ability of the copper and the copper compound is insignificant. There is a problem in that the dissolution and storage stability of the azole compound is insignificant.

The present invention also provides a water treatment method in which the water treatment agent composition of the present invention is introduced into a cooling tower, a heat exchanger, and / or various drain pipes to suppress corrosion of metal in water and scale formation.

In the water treatment method, the concentration of the water treatment agent composition is preferably 1 to 500,000 ppm with respect to the cooling water.

When the concentration of the water treatment agent composition is less than 1 ppm with respect to the cooling water, the metal and scale suppression functions are insignificant. When the concentration of the water treatment agent composition exceeds 500,000 ppm, the effect of the water treatment agent composition does not increase in proportion to the concentration of the added water treatment agent composition. There is a problem.

As described above, the water treatment agent composition of the present invention has excellent metal corrosion and scale suppression effect in a wide range of water quality, and is easy to use and easy to adjust pH in an open circulation cooling system.

Hereinafter, preferred examples and comparative examples of the present invention are described. The following examples and comparative examples are described for the purpose of more clearly expressing the present invention, but the contents of the present invention are not limited to the following examples and comparative examples.

(Examples 1 to 5 and Comparative Examples 1 to 5)

The corrosion rate of carbon steel was measured by using potentiostat, an electrochemical measurement method at 25 ° C. and 160 rpm. The corrosion rate of the carbon steel after maintaining the 100 ppm concentration of the water treatment composition of Examples 1 to 5 shown in Table 2 and the water treatment composition of Comparative Examples 1 to 5 shown in Table 3 in the test water quality of Table 1 below mils per year) is shown in Table 4 below. The corrosion rate was determined by measuring a tafel curve. mils is 1/1000 inch.

Water quality One 2 3 4 5 pH 8.5 8.4 8.3 8.2 8.1 Calcium Hardness (ppm) 100 200 300 400 500 Methyl Orange-Alkalido (ppm) 120 110 100 85 75 Magnesium hardness (ppm) 20 40 60 80 100 Chlorine Ion (ppm) 71 142 213 284 355

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

ingredient Content (% by weight) Example 1 Example 2 Example 3 Example 4 Example 5 Water (pure) 79 82.5 85.5 87.5 76 Organic Phosphate-1 2 4 5 6 4 Organic Phosphate-2 2 One One One 4 Azole compound 2 1.5 One 0.5 3 Acrylate polymer 10 7 5 4 3 Alcohol 5 4 2.5 One 10

In Table 2, organic phosphate-1 is hydroxyethylidene diphosphonic acid (HEDP, manufactured by LONZA), organic phosphate-2 is phosphono butanetri carboxylic acid (PBTC, manufactured by BAYER), and an azole type. The compound is tolyltriazole, the acrylate polymer is Belcrene 400 (manufactured by BIOLAB), and the alcohol is methyl alcohol.

ingredient Content (% by weight) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Water (pure) 100 95.5 93 96 96 Caustic Soda (NaOH) 0 2 2 0 6 Organic Phosphate-1 0 0 0 2 0 Organic Phosphate-2 0 0 0 2 0 Azole compound 0 0 0 0 2 Acrylate polymer 0 0 5 0 0 Alcohol 0 2.5 0 0 0

In Table 3, organic phosphate-1 is hydroxyethylidene diphosphonic acid (HEDP, manufactured by LONZA), organic phosphate-2 is phosphono butane tricarboxylic acid (PBTC, manufactured by BAYER), and an azole type. The compound is tolyltriazole, the acrylate polymer is Belcrene 400 (manufactured by BIOLAB), and the alcohol is methyl alcohol.

(Unit: mpy) Water quality One 2 3 4 5 Example 1 0.84 0.96 1.08 1.25 1.54 Example 2 0.48 0.66 0.79 0.87 0.97 Example 3 0.35 0.41 0.47 0.56 0.82 Example 4 0.28 0.38 0.42 0.46 0.52 Example 5 0.44 0.50 0.58 0.63 0.84 Comparative Example 1 8.08 8.25 9.12 9.67 10.05 Comparative Example 2 8.15 8.22 8.89 9.76 9.98 Comparative Example 3 7.69 7.98 8.02 8.39 8.49 Comparative Example 4 2.58 3.69 4.25 4.58 5.78 Comparative Example 5 7.45 7.66 7.89 7.96 8.01

As shown in Table 4, when the corrosion resistance of the carbon steel is tested using the water treatment agent compositions of Examples 1 to 5 of the present invention, it can be seen that the corrosion strength of the carbon steel is significantly lower than that of the water treatment agent compositions of Comparative Examples 1 to 5.

Scale performance test method

After the test solution was sealed and allowed to stand at 70 ° C. for 24 hours, the test solution was filtered through a 0.45 macro filter, and the total hardness at this time was measured to measure scale inhibition using Equation 1 below. At this time, the water treatment agent composition of Examples 1 to 5 shown in Table 2 and the water treatment agent composition of Comparative Examples 1 to 5 shown in Table 3 were maintained in a concentration of 100 ppm in the test water quality of Table 1, and then the scale inhibition rate was tested. The results are shown in Table 5 below.

[Equation 1]

In Formula 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.

(unit : %) Water quality One 2 3 4 5 Example 1 100 100 100 98 95 Example 2 100 100 100 98 95 Example 3 100 100 100 98 98 Example 4 100 98 97 96 95 Example 5 100 96 97 96 90 Comparative Example 1 80 68 48 48 35 Comparative Example 2 72 64 48 44 30 Comparative Example 3 90 80 77 76 65 Comparative Example 4 90 80 77 72 60 Comparative Example 5 72 60 48 40 30

As shown in Table 5, when the scale performance test using the water treatment composition of Examples 1 to 5 of the present invention it can be seen that the scale inhibition rate is significantly improved compared to the water treatment composition of Comparative Examples 1 to 5.

PH drop test method of test solution

In order to apply to cooling water with high concentration and pH, the pH rise of cooling water should be suppressed as much as possible. Therefore, the pH drop test of the test solution was performed to determine suitability. At this time, the pH of the water treatment agent compositions of Examples 1 to 5 shown in Table 2 and the water treatment agent compositions of Comparative Examples 1 to 5 shown in Table 3 were respectively maintained in the test water quality of Table 1 at a concentration of 100 ppm. The results are shown in Table 6 below.

(Unit: pH) Water quality One 2 3 4 5 Example 1 8.1 8.0 7.8 7.5 7.4 Example 2 8.2 8.1 7.7 7.5 7.4 Example 3 8.1 7.8 7.7 7.5 7.3 Example 4 8.0 7.8 7.6 7.4 7.3 Example 5 8.0 7.8 7.6 7.4 7.3 Comparative Example 1 8.5 8.4 8.3 8.2 8.1 Comparative Example 2 8.5 8.4 8.3 8.2 8.1 Comparative Example 3 8.8 8.7 8.6 8.5 8.5 Comparative Example 4 8.3 8.2 8.0 7.8 7.7 Comparative Example 5 8.8 8.7 8.6 8.5 8.5

As shown in Table 6, when the pH drop test using the water treatment composition of Examples 1 to 5 of the present invention it can be seen that the pH drop effect is significantly superior to the water treatment composition of Comparative Examples 1 to 5.

The water treatment composition of the present invention is excellent in metal corrosion and scale suppression effect in a wide range of water quality, easy to adjust pH and easy to use in open circulation cooling system.

Claims (8)

(a) 0.5 to 40 weight percent of phosphonate; (b) 0.1 to 30% by weight of acrylate polymer; (c) 0.1 to 10% by weight of an azole compound; (d) 0.1 to 20% by weight of alcohol; And (e) water balance Water treatment agent composition comprising a. The method of claim 1, wherein (a) the phosphonate is hydroxy ethylidine diphosphonic acid, hydroxy phosphono carboxylic acid, amino trimethylene phosphonic acid, phosphono butane tri carboxylic acid and ethylene diamine tetra methylidine A water treatment composition selected from the group consisting of phosphonic acids. The water treatment composition of claim 1, wherein the (b) acrylate polymer is of the following Chemical Formula 1: [Formula 1] In Formula 1, l, m and n may be the same or different from each other, each independently represent an integer of 0 to 1,000, R is hydrogen, methyl or carboxyl group, when R is a carboxyl group is bonded to an adjacent carboxyl group anhydrous ring anhydrous ring), R ₁ and R ₈ may be the same or different from each other, and each independently hydrogen, an alkyl group, a hydroxy group or a phosphono group, and R ₂ and R ₃ may be the same or different from each other, Independently hydrogen or a C ₁ -C ₂ alkyl group, R ₄ is hydrogen or a C ₁ -C ₅ alkyl group, R ₅ is a C ₁ -C ₈ alkyl group or a C ₈ -C ₁₀ aralkyl group, and X and Y are each other the same or be different, and each independently hydrogen, hydroxy alkyl of C ₁ -C ₅ alkyl group or a C ₁ -C _5, R ₀ is selected from the group consisting of a compound represented by the following formula 2, 3 and 4 will be. [Formula 2] [Formula 3] [Formula 4] In Formulas 2 to 4, R ₆ and R ₁₂ may be the same or different from each other, each independently hydrogen or an alkyl group of C ₁ -C ₂ , R ₁₃ and R ₁₄ may be the same or different from each other, each independently Hydrogen, an alkyl group of C ₁ -C ₈ , a cycloalkyl group of C ₆ -C ₈ , a benzyl group or a compound of formula 5, R ₇ is an alkyl group of C ₁ -C ₆ , an allyl group of C ₆ -C ₁₀ , C An aralkyl group of ₆ -C ₁₀ or a compound of formula (5). [Formula 5] In Formula 5, i is 1, 2 or 3, R ₉ is hydrogen or an alkyl group of C ₁ -C ₂ , R ₁₀ is hydrogen or an alkyl group of C ₁ -C ₆ . The water treatment composition of claim 1, wherein the (c) azole compound is selected from the group consisting of tolyltriazole, mercapto benzothiazol, benzotriazole and imidazole. The water treatment composition of claim 1, wherein the alcohol (d) is selected from the group consisting of methyl alcohol, ethyl alcohol and isopropyl alcohol. A mixture of phosphonate, acrylate polymer and water and a mixture of an azole compound, alcohol and water in a weight ratio of 99: 1 to 70:30. A water treatment method, wherein the water treatment agent composition according to any one of claims 1 to 5 is introduced into a cooling tower, a heat exchanger, and / or various waste pipes to suppress corrosion of metals in water and formation of scale. The method of claim 7, wherein the concentration of the water treatment agent composition is 1 to 500,000 ppm with respect to the cooling water.