JP2708082B2 - One-part type water treatment agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel one-part water treatment agent,
More specifically, in addition to being able to simultaneously prevent metal corrosion, scale and generation of slime and algae, it is low toxic, has improved stability over time and solubility of each component, and is foamless and easy to handle. The present invention relates to a one-part water treatment agent having characteristics and preferably used for a circulating cooling water system, a cooling / heating water system, and related devices thereof.

[0002]

2. Description of the Related Art In recent years, a large amount of cooling water is used in various industrial fields, for example, in the chemical industry and the steel industry, for the purpose of indirectly or directly cooling an object to be treated, or for cooling and heating or air conditioning of a building. Have been. In order to reduce the use of cooling water from the viewpoint of water resources shortage and effective use, an advanced cooling water utilization method is used, for example, a reduction in the amount of forced blow water under a high concentration operation of an open circulation type cooling water system. Have been. If such a cooling water advanced utilization method is implemented, the quality of the circulating cooling water will deteriorate due to the concentration of dissolved salts, etc., and failures caused by water, such as metal corrosion and scale formation occurring in the cooling water system, will occur. It is accompanied by the disadvantage that the generation is significant.

[0003] On the other hand, in such a circulating cooling water system, a normal cooling water system, or a cooling and heating water system, microorganisms such as bacteria, mold, and algae that have propagated by utilizing nutrients dissolved in water are affected by sediment and dust. Oozy contaminants, which are formed by mixing such as, so-called slime and algae,
It causes various obstacles, such as a decrease in heat efficiency in the heat exchanger, deterioration of water flow, or local corrosion of equipment and piping.

[0004] Therefore, in order to prevent such metal corrosion, scale, and generation of slime and algae, an additive agent is used correspondingly. For example, in order to prevent metal corrosion, conventionally, phosphonic acid and salts thereof, benzotriazole and tolyltriazole, zinc salts and the like are used as anticorrosives, depending on the material of the metal, as appropriate.
In recent years, molybdate has attracted attention as an excellent anticorrosive and has begun to be used.

Further, in order to prevent deposition on the heat transfer surface of a heat exchanger such as calcium salts such as calcium carbonate and calcium phosphate, magnesium silicate and iron hydroxide, the above-mentioned phosphonic acid and phosphonic acid have been used as scale inhibitors. Salts thereof, relatively low molecular weight polyacrylic acid, polymaleic acid, other various copolymers and terpolymers, and salts thereof are used.

On the other hand, in order to prevent the generation of slime and algae, various fungicides and algicides such as inorganic chlorine compounds, hydrazine, and organic halogen compounds have been used. Attention has been directed to polymers and they are beginning to be used.

As for the use of these chemicals, a chemical for preventing metal corrosion and the generation of scale and a chemical for preventing the generation of slime and algae are separately added. From the viewpoint of efficiency of addition work and simplification of addition equipment, the above three kinds of drugs are mixed,
It is desirable to add as a multi-type one-part water treatment agent, but a one-part water treatment agent that is sufficiently satisfactory in terms of solubility of each component and stability over time has been found. There is no actual situation.

[0008] Some multi-type water treatment agents in which the powder component is solidified for small cooling towers are commercially available, but they are soluble in water (sustained release that always maintains a constant effective concentration). )
However, it is not always practical.

[0009]

SUMMARY OF THE INVENTION Under the above circumstances, the present invention can simultaneously prevent metal corrosion, scale, slime and algae generation, and has low toxicity, stability over time, and the stability of each component. It is an object of the present invention to provide a practical multi-type one-pack water treatment agent having improved solubility.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to develop a multi-type practical one-part water treatment agent. It has been found that the object can be achieved by containing each of the specific components each having an algae development inhibiting action as an active ingredient, and the present invention has been completed based on this finding.

That is, the present invention relates to the following (A):

Embedded image (Wherein n is an integer of 4 to 40), a combination of a water-soluble cationic polymer represented by the formula (B): phosphonic acids, (C) molybdate, (D) benzotriazoles, and (E) a zinc-containing compound. Is provided as an active ingredient.

In the water treatment agent of the present invention, the water-soluble cationic polymer used as the component (A) is represented by a general formula:

Embedded image (Wherein n is an integer of 4 to 40), poly [oxyethylene (dimethylimino) ethylene (dimethylimino) ethylene dichloride] is used.

This is a slime inhibitor which is completely dissolved in water and exhibits slight acidity and has an excellent anti-algal and anti-bacterial effect. It is a conventional bactericide such as a cationic polymer or a quaternary ammonium salt. Has the disadvantage of being extremely foamable, but has the characteristics of being substantially non-foamable and non-irritating, and is characterized by N, N, N ', N'-tetramethylethylenediamine and dichloromethane. It can be easily produced by reaction with ethyl ether. This cationic polymer effectively exerts the effect of preventing the generation of slime and algae when the concentration in water is usually in the range of 0.1 to 100 ppm. The preferred concentration is selected in the range of 0.2 to 30 ppm.

The phosphonic acids used as component (B) include, for example, 1-hydroxyethylidene-1,1-
Preferable examples include diphosphonic acid, aminotrimethylenephosphonic acid, and alkali salts such as sodium salt, potassium salt, and ammonium salt thereof. These may be used alone or in combination of two or more.

These phosphonic acids are scale inhibitors having the functions of industrial water treatment agents such as polyphosphates, phosphates, polymers, chelating agents and the like. It has an effect of effectively preventing deposition and adhesion of calcium sulfate, barium sulfate, ferric hydroxide and the like. In addition, it has been recognized that, when used in combination with an anticorrosive such as a benzotriazole as the component (D) or a zinc-containing compound as the component (E), the anticorrosive effect is exhibited by a synergistic effect as well as a scale preventive effect. The concentration in water is desirably in the range of 1 to 20 ppm in order to effectively exhibit the scale prevention effect, and 1 to 10 ppm in order to effectively exhibit the anticorrosion effect by the synergistic effect.
A degree is enough.

The molybdate used as the component (C) includes, for example, alkali molybdate such as sodium molybdate and potassium molybdate. The molybdate acts as an oxide film type anticorrosive, and particularly exhibits an excellent corrosion inhibitory effect on iron as an anode type inhibitor. However, the effect is low unless used alone at a high concentration, but a synergistic effect is exhibited when used in combination with other anticorrosives. Its concentration in water is usually 1
Although it is selected in the range of about 50 ppm, a synergistic effect is exhibited even in the range of about 1 to 5 ppm.

The benzotriazoles used as component (D) include, for example, 1,2,3-benzotriazole and tolyltriazole, among which 1,2,3-benzotriazole is preferred. .
These benzotriazoles combine with a metal, particularly a copper plate, to form a protective film, and exhibit an excellent inhibitory effect on copper corrosion.

Examples of the zinc-containing compound used as the component (E) include zinc sulfate and zinc nitrate. Of these, zinc nitrate is preferred from the viewpoint of solubility and the like. This zinc-containing compound acts as a cathode-type inhibitor, and exhibits a synergistic effect when used in combination with another anticorrosive.

The one-part water treating agent of the present invention comprises (A) 1 to 30% by weight of a water-soluble cationic polymer and (B) 1 to 30% by weight of phosphonic acids in an aqueous medium based on the total weight of the water treating agent. , (C) 1 to 10% by weight of molybdate, (D) 0.5 to 5% by weight of benzotriazoles and (E) 0.5 to 5% by weight of a zinc-containing compound, and homogeneously dissolve them. Can be prepared.

The pH of the water treatment agent thus obtained is desirably in the range of 5 to 7. When the pH is less than 5, the type and amount of each component, particularly the type and amount of phosphonic acid, are used. Depending on the case, cloudiness may occur or storage stability may be deteriorated, and the anticorrosion effect may not be sufficiently exhibited. When the value exceeds 7, especially when it is 9 or more, storage stability tends to be deteriorated.

The pH may be adjusted by using a free phosphonic acid and an alkali salt of a phosphonic acid in an appropriate ratio in combination, using an alkali such as sodium hydroxide or potassium hydroxide, or adding hydrochloric acid or sulfuric acid. And the like.

Next, an example of a preferred method for preparing the one-part water treatment agent of the present invention will be described. First, a relatively sparingly soluble benzotriazole is mixed with a solubilizing agent such as diethylene glycol 3 to 8 times by weight. After adding and moistening to the extent,
An aqueous medium such as water is added thereto, and the mixture is thoroughly stirred to dissolve the benzotriazoles, and then phosphonic acids are added and dissolved. At this time, when two or more phosphonic acids are dissolved, it is preferable to add an alkaline one first, and then add an acidic one.

Next, a zinc-containing compound is added and dissolved, and then molybdate is added and dissolved. Then, if necessary, an alkali such as sodium hydroxide or potassium hydroxide,
Alternatively, the pH is preferably adjusted to 5 to 7 using an acid such as hydrochloric acid or sulfuric acid, and then the water-soluble cationic polymer is added and dissolved to obtain the one-part water treatment agent of the present invention.

[0024]

The water treatment agent of the present invention is a multi-part, one-pack type, which can simultaneously prevent metal corrosion, scale and slime and algae generation, and has low toxicity, stability over time, and It has characteristics such as good solubility, non-foaming and easy handling, and is suitably used for, for example, a circulating cooling water system, a cooling / heating water system, and related devices.

[0025]

Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

Example 1 0.8 parts by weight of benzotriazole was wetted by adding 3 parts by weight of diethylene glycol, and then a predetermined amount of water was added. The mixture was stirred thoroughly to dissolve the benzotriazole, and then 1-hydroxyethylidene- The drug [phosphonic acid (I)] containing 60% by weight of 1,1-diphosphonic acid was added and dissolved in the amount shown in Table 1, and then 1.0 part by weight of zinc nitrate was added and dissolved, and then sodium molybdate was further added. 4.0 parts by weight were added and dissolved. Next, without adding sodium hydroxide or after adding the amount shown in Table 1, a drug (WSCP) 8.0 containing 60% by weight of poly [oxyethylene (dimethylimino) ethylene (dimethylimino) ethylene dichloride] was added. A one-part water treatment agent having the composition shown in Table 1 was prepared by adding and dissolving parts by weight.

The pH, appearance and storage stability of this one-part water treatment agent were determined, and the results are shown in Table 1.

The storage stability was 4 weeks at -5.degree.
The appearance after each standing at 0 ° C. for 4 weeks was observed and determined according to the following criteria. ：: no change, △: colored brown, ×: turbid and aggregated

[Table 1]

As can be seen from Table 1, the phosphonic acid (I)
Water treatment agent A containing 10% by weight is cloudy at pH 2 and has poor storage stability. In contrast, phosphonic acid (I)
Water treatment agents BF containing 15.0% by weight or more are acidic, but are transparent and have good storage stability.

Example 2 In the same manner as in Example 1, a one-pack type water treatment agent having the composition shown in Table 2 was prepared. However, phosphonic acids (I) and (II)
In the case of using (a drug containing 60% by weight of sodium salt of 1-hydroxyethylidene-1,1-diphosphonic acid), (I) was added after (II) was added.

The pH, appearance and storage stability of this one-pack type water treatment agent were determined in the same manner as in Example 1, and the results are shown in Table 2.

[Table 2]

From Table 2, it can be seen that cloudiness and storage stability are affected by differences in composition and pH.

Example 3 In the same manner as in Example 1, one-part water treatment agents shown in Table 3 were prepared, and the pH, appearance and storage stability were determined. Table 3 shows the results. However, the pH was not adjusted with a pH adjuster.

[Table 3]

Test Example 1 Using the one-part water treatment agent shown in Table 4, the bacteria shown in Table 4
The antibacterial and antialgal effects against filamentous fungi and algae were evaluated by determining the minimum inhibitory concentration that suppresses the growth of various microorganisms. Table 4 shows the results.

[Table 4]

Test Example 2 2 l of corrosive water (0.165 g of NaCl, NaHCO
₃ 0.138 g, Na ₂ SO ₄ 0.148 g / l)
One-part water treatment agents of the type shown in Table 5 were used at concentrations of 0,50,
A test piece (100 × 50 × 2 mm) of a steel plate (SPCC), a copper plate, an aluminum plate, and a galvanized plate is suspended in the solution, and circulated through a pump for 9 days. Corrosion rate (mg /
dh / day, mdd), and the results are shown in Table 5.

[Table 5]

Test Example 3 A cooling tower having a cooling tower capacity of 250 RT and a retained water of 1.5 tons was used, and the amount of makeup water: 23.4 tons of industrial water /
On the day, the concentration ratio was 10 times, and the one-part water treatment agent N was added to the make-up water so that the active ingredient concentration became 100 ppm, and the continuous operation was performed for 6 months.

As a result, no scale formation was found to be an obstacle in the heat exchange tube and the machine, and the test pieces (100 × 50 × 2 mm) of the steel plate (SPCC), copper plate and aluminum plate suspended in the machine were not observed. The corrosion rates were 0.7, 0.02 and 0.01 mdd, respectively.

Further, no generation of slime or algae was observed, and no high-pressure cut occurred during the period.

As can be seen from the above results, when the phosphonic acid (I) is used alone, the treatment agent becomes transparent if it is used in an amount of 15% by weight or more, but it becomes strongly acidic. A large amount of alkali must be added to
Affects other components, especially WSCP, and has an effect on bactericidal and anti-algal effects (water treatment agent D). Further, those prepared by combining the acidic phosphonic acid (I) and the alkaline phosphonic acid (II) to adjust the pH to 5 to 7 maintain the storage stability and the respective effects, and have good solubility of each component. , Becomes transparent. When the pH of the water treatment agent is 9 or more, the storage stability tends to deteriorate.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication location C23F 11/18 C23F 11/18 (72) Inventor Masaaki Kojima 4-1-2, Ginza, Chuo-ku, Tokyo No. Somar Co., Ltd. (56) References JP-A-58-199878 (JP, A)

Claims (7)

(57) [Claims] (A) General formula (1) (Wherein n is an integer of 4 to 40), a combination of a water-soluble cationic polymer represented by the formula (B): phosphonic acids, (C) molybdate, (D) benzotriazoles, and (E) a zinc-containing compound. One-part water treatment agent comprising as an active ingredient. 2. Component (A) 1 to 30% by weight, component (B) 1 to 30% by weight, component (C) 1 to 10% by weight, component (D) 0.5 to 5% by weight, component (E) The one-part type water treatment agent according to claim 1, comprising 0.5 to 5% by weight of a component. 3. The one-part water treatment agent according to claim 1, wherein the pH is in the range of 5 to 7. 4. The method according to claim 1, wherein the phosphonic acids are at least one selected from 1-hydroxyethylidene-1,1-diphosphonic acid, aminotrimethylenephosphonic acid and alkali salts thereof. The one-part water treatment agent according to the above. 5. The one-part water treatment agent according to claim 1, wherein the molybdate is an alkali salt of molybdate. 6. The one-part water treatment agent according to claim 1, wherein the benzotriazole is 1,2,3-benzotriazole. 7. The one-part water treatment agent according to claim 1, wherein the zinc-containing compound is at least one selected from zinc sulfate and zinc nitrate.