KR100484288B1 - One component type composition for sterilizing of microorganism and inhibiting of scale in cooling water - Google Patents

Abstract

To provide an one component type sterilizing and scale preventing composition in which 3-methyl-isothiazolone mixture is mixed with sodium polyacrylate, the composition capable of maintaining consistent sterilization effect and preventing scale at the same time. An one component type sterilizing and scale preventing composition comprises 80 to 90 wt.% of 3-methyl-isothiazolone and 10 to 20 wt.% of sodium polyacrylate, wherein the 3-methyl-isothiazolone is a mixture in which 2-methyl-4-isothiazolin-3-one is mixed with 5-chloro-2-methyl-4-isothiazolin-3-one in a weight ratio of 1:1 to 1:5, and 0.1 to 1 wt.% of water or an organic solvent is diluted in the composition, the organic solvent selected from the group consisting of ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, 1,5-pentanediol and benzyl alcohol.

Description

One component type composition for sterilizing of microorganism and inhibiting of scale in cooling water}

 The present invention relates to a one-component sterilization and anti-scaling composition used inside the pipe, and more particularly 3-methyl-iso to enable sterilization effect and scale prevention of bacteria including Legioella bacteria which are the most problematic in the cooling water system. A one-part bactericidal and anti-scaling composition consisting of thiazolone and sodium polyacrylate.

Typically, Legioella bacteria are negative bacteria, aerobic pathogens (length: 0.3 ~ 0.9㎛), resistant to chlorine compared to gut bacteria, and iron contained in cooling water promotes their growth and is present in almost all natural water. It is known.

In addition, Legionella bacteria can be transported through water pipes and are not completely sterilized by safe treatment methods for drinking water, and most of them are killed at temperatures above 65 ° C, but the fertility is very high near 37 ° C (double growth in 8 hours). There is a lurking characteristic at very low temperatures, especially because the growth of the cooling water at a normal temperature rapidly, threatening the health of people in buildings and houses that heat and cool.

Thus, conventionally, in order to sterilize the Legionella, the sterilization method using hypochlorite, silicate, phosphate was performed.

However, the above sterilization method may corrode metals used in facilities such as pipes, and since the effect on the sterilizing power is not complete with a single product, a need for a non-oxidizing fungicide to replace it has emerged.

Therefore, recently, many isothiazolone compounds having a wide range of bactericidal activity against microorganisms harmful to the human body such as bacteria, fungi, and premature ejaculation have been used.

However, the isothiazolone compound has a problem in that the sterilizing effect decreases with time in a solution using water or an organic solvent.

To solve the above problems, Korean Patent Laid-Open Publication No. 2003-0093097 discloses a composition comprising a compound such as an alkali metal nitrate, an alkali metal chloride salt, an iodic acid, a chloride salt, and water and an organic solvent in a 3-isothiazolone compound. In order to improve the stability of the 3-isothiazolone compound to water or an organic solvent, the nitrate or chloride salts in the composition are combined with the metals in the cooling water, are easily precipitated, and are used in equipment such as piping. Still has the disadvantage of corroding.

In addition, in the cooling water system, not only the sterilization but also the efficiency reduction of the equipment by the scale (Scale) is a problem, and the common causes of the generation of the complex is the combined action of pH, calcium hardness, alkalinity, total solids and temperature of the cooling water. The scale types produced were calcium carbonate (CaCO ₃ ), calcium sulfate (CaSO ₄ ), zinc phosphate [Zn ₃ (PO ₄ )] and calcium phosphate [Ca ₃ (PO ₄ ) ₂ ] Etc. can be mentioned.

In addition, the typical calcium salt reacts with the ionic components dissolved in water, and most of them are precipitated when they reach the saturation state, and are attached to the crystal surface on the heat transfer surface, causing energy waste and shortening the lifespan of the equipment.

Therefore, in recent years, the development of a single product that can simultaneously solve the scale as well as sterilization of harmful strains in the cooling water system.

 Accordingly, the present inventors have attempted to develop a one-component sterilization and anti-scaling agent composition which has isothiazolone as a main component and can be conveniently used for cooling water of a cooling tower. Sodium polyacrylate, which serves as isothiazolone and a dispersant in water or an organic solvent, (Sodium Polyacrylate) is proved that the stability of the isothiazolone is improved by dissolving in a predetermined compounding ratio to have a continuous sterilizing effect in the one-component composition while at the same time to prevent the scale of the cooling water sterilization and cooling of the present invention The prevention composition was completed.

Accordingly, it is an object of the present invention to provide a one-part bactericidal and anti-scale composition comprising a mixture of 3-methyl-isothiazolone mixture and sodium polyacrylate.

 In order to achieve the above object, the present invention provides a one-component sterilization and anti-scaling composition comprising 80 to 90% by weight of 3-methyl-isothiazolone and 10 to 20% by weight of sodium polyacrylate.

Hereinafter, the present invention will be described in detail.

At this time, if there is no other definition in the technical terms and scientific terms used, it has a meaning commonly understood by those of ordinary skill in the art.

 In addition, repeated description of the same technical configuration and operation as in the prior art will be omitted.

The present invention is the sterilization of Legioella by 3-methyl-isothiazolone, which is an organic nitrogen sulfur halogen-based complex, and sodium polyacrylate [Sodium Polyacrylate; (C ₃ H ₄ O ₂ ) _X • XNa, X is a one-part bactericidal and anti-scaling agent composition including a scale prevention action by X.

The 3-methyl-isothiazolone mixture used in the present invention is a compound having a wide range of bactericidal activity against harmful strains such as bacteria and fungi, and is widely used as a substance which is added to cosmetics and paints to inhibit the growth of harmful microorganisms. This is because the strain is inhibited due to the reaction between the NS bond (active ingredient) of the 3-methyl-isothiazolone mixture and the electrophilic cell constituent of the strain.

At this time, in the present invention, the 3-methyl-isothiazolone mixture is 2-methyl-4-isothiazolin-3-one (MIT) of Formula 1 having no halogen element and 5- of Formula 2 having halogen element. It is preferable to use chloro-2-methyl-4-isothiazolin-3-one (CMIT) in a weight ratio of 1: 1 to 1: 5. This is because the mixture generally has a wide range of effects on gram positive and negative bacteria, has excellent compatibility with nonionic, anionic and cationic surfactants, and has a lower minimum concentration of CMIT than MIT without halogen, This is because the bactericidal effect is better. However, when the CMIT is 5 or more based on MIT 1, the solubility decreases, so that the sterilization effect may be lowered due to the precipitation reaction caused by the cooling water and its own reaction in the composition.

[Formula 1]

[Formula 2]

In addition, in the present invention, it is preferable to use a solution diluted with the mixture and the diluting solvent. When the composition of the present invention is used as a powder, it is difficult to uniformly mix in the cooling water and it is difficult to handle because the amount is small. This is because, in the case of a solution, it is easy to inject it into cooling water uniformly, and since it is diluted, it is convenient to handle.

And, sodium polyacrylate used in the present invention [Sodium Polyacrylate; (C ₃ H ₄ O ₂ ) _X ㆍ XNa, X is a positive integer] is a water-soluble, low molecular weight acrylic copolymer that is harmless to the human body and possesses the characteristics of a gelling agent with strong adsorptive power. While suppressing, it exhibits an excellent effect in dispersing insoluble sludge and mineral slurry and the like, and is a compound having excellent stability to heat and water resistance, thereby allowing stable mixing even when mixed with 3-methyl isothiazolone.

In addition, the product formed by gelling due to the sodium polyacrylate is also rapidly decomposed by an aqueous electrolyte solution such as sodium chloride (NaCl), potassium chloride (KCl) or calcium chloride (CaCl ₂ ) has a characteristic that does not cause problems when draining.

At this time, in the present invention, 10 to 20% by weight of sodium polyacrylate is used, which decreases the gelling ability when using less than 10% by weight, the dispersant effect is insignificant, when using more than 20% by weight due to excessive gelation phenomenon This can cause problems with drainage.

On the other hand, in addition to the properties of the above-described individual components, the mixing of the components in the present invention generally exhibits an excellent effect than the sterilization by chlorine acid, phosphate, silicate, inorganic, such as carbonate scale, calcium phosphate salt scale and zinc Maximize the efficiency of cooling water management by preventing or dispersing deposits.

In addition, since the composition of the present invention should be dosed at a dose of 0.1 to 1 mg per liter of cooling water, it is preferable to use a solution of 0.1 to 1% by weight of 3-methyl-isothiazolone. This is because when administered to the cooling water is less than 0.1% by weight, when selling, there is a disadvantage in that the container capacity of the finished product increases in size, and when it is more than 1% by weight is too small.

At this time, the diluent solvent in the solution of the composition is water or organic selected from the group consisting of ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, 1,5-pentanediol and benzyl alcohol Preference is given to using a solvent.

In addition, the mixture composition of the present invention is a known additive, that is, a surfactant, an antioxidant for synergistic effects in addition to the components described above. Adjuvants such as dispersants, thickeners and stabilizers may be used in a predetermined amount, depending on the relationship of the material reactions, which can be used by any person skilled in the art by mixing effective ratios of the adjuvant. It is.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to Examples, but the scope of the present invention is not limited to these Examples.

Example 1 Preparation of one-component composition of the present invention

2-methyl-4-isothiazolin-3-one (CAS No 2682-20-4) and 5-chloro-2-methyl-4-isothiazolin-3-one (CAS No 26172-55-4) 9 g of 3-methyl-isothiazolone mixed at a weight ratio of 1: 3 and 1 g of sodium polyacrylate (CAS No 9003-04-7) are uniformly mixed with a small amount of water to dissolve, and the total weight is 1,000 g. Was further added to complete the one-component composition of the present invention.

Example 2 Test of Sterilization Effect on Cooling Water

 This embodiment is to treat the composition of the present invention in the cooling water to confirm the sterilization and anti-scaling effect of Legionella bacteria on the cooling water of the composition of Example 1 according to the present invention, and then the bacterial (colony) water and cooling water of Salmonella The total hardness of the calcium carbonate was measured.

At this time, prior to the experiment, the one-component composition of Example 1 was used by diluting 100 times with 99 g of water in 1 g for ease of use.

2-1. Legionella bactericidal effect

Then, the diluted composition was adjusted to 1 g (minimum concentration: 0.1 mg / L) per 10 L of cooling water in the selected 10 cooling towers, and administered twice a week. Then, two weeks after the treatment, 500 ml of each of the cooling water was collected with a sterile water bottle, and the collected cooling water was filtered with cellulose nitrate filtration membrane, and then cultured in each medium at 35 ± 1 ° C. for 5 days. Survival was observed.

At this time, the control was measured for survival of Legionella bacteria in the cooling water not treated with the disinfectant.

As a result, as shown in Table 1, in the composition according to the present invention it was found that no two strains of Legorel bacteria after two weeks of treatment.

division Legionella bacteria count before treatment After 2 weeks Legionella bacteria One 2.10 × 10 ⁵ 0 2 1.90 × 10 ⁵ 0 3 2.10 × 10 ⁶ 0 4 2.00 × 10 ⁶ 0 5 1.20 × 10 ⁵ 0 6 2.30 × 10 ⁶ 0 7 2.10 × 10 ⁵ 0 8 2.20 × 10 ⁶ 0 9 1.90 × 10 ⁵ 0 10 2.80 × 10 ⁵ 0 Control 2.10 × 10 ⁵ 7.00 × 10 ²

2-2. Scale prevention effect

In order to measure the anti-scaling effect, the composition of the present invention was treated in the same manner as in the method of 2-1, and after 2 weeks, 500 ml of each of the sterile bottles was collected, and the total hardness was measured by EDTA titration. The total hardness is expressed in mg number of 1 L of the sample in terms of the amount of calcium ions and magnesium ions in water, and the corresponding calcium carbonate. The test method was KS M 0100: 1988 (I.C.P).

As a result, as shown in Table 2 below, the calcium hardness of the cooling water by treatment of the composition of the present invention is 150mg CaCO3 / meets the following criteria: The average calcium carbonate hardness of 69% (up to 85% and at least 52%) was found to be removed.

division Total hardness before feeding (mg CaCO ₃ / ℓ) Total hardness after 2 weeks of treatment (mg CaCO ₃ / ℓ) One 382 85 2 217 32 3 187 77 4 254 120 5 450 90 6 276 132 7 326 125 8 473 98 9 337 130 10 320 53

In addition, in order to compare the anti-scaling effect between the composition of the present invention and a conventionally marketed product, three cooling towers 200R / T of the same capacity are first selected, and the composition of Example 1 and the Cooling water treatment agent (Product S) and company B's cooling water treatment agent (Product D) were charged according to the amount specified for each product.

Then, 500 ml of cooling water was taken from each cooling tower every week for four weeks after the treatment, and the total hardness was measured to compare the scale prevention ability of the product according to the treatment time.

As a result, as shown in Table 3 and Figure 1, the calcium hardness of the cooling water by the treatment of the composition of the present invention is 150mg of the refrigeration, air conditioning cold water quality standard (draft) M 0077-1988 standards It shows the effect that meets the criteria of CaCO ₃ / ℓ or less, and after 2 weeks faster than other products, it shows the effect that meets the management standard.After 4 weeks, S decreases 71% and B decreases 66%. On the other hand, the composition of the present invention was found to be very excellent effect such as reducing to 85%.

From this, the composition of the present invention can be managed at a lower level than the quality standard of the cooling water, and the hardness of the calcium carbonate is removed or prevented the effect is more than 15 to 20% better after 4 weeks than similar products. Proved.

product Before input (mgCaCO ₃ / ℓ) After 1 week (mgCaCO ₃ / ℓ) After 2 weeks (mgCaCO ₃ / ℓ) After 3 weeks (mgCaCO ₃ / ℓ) After 4 weeks (mgCaCO ₃ / ℓ) S company product 530 482 382 253 152 Company B 642 554 477 330 214 Example 1 (Invention) 552 220 148 112 78

 As such, the composition of the present invention can improve the stability of 3-methyl-isothiazolone in water or an organic solvent to prepare a one-component composition, and simultaneously perform complete sterilization and excellent scale prevention or inhibition against Legioella. It can work.

 Therefore, the composition of the present invention provides the anti-scaling effect of the most commonly occurring harmful bacteria in the cooling water system and the energy efficiency of the facility, thereby maximizing the efficiency of cooling water management.

1 is a graph showing the effect of reducing the scale according to the treatment time after the treatment of the composition of the present invention and other products in the cooling water.

Claims (3)

A composition consisting of 80-90% by weight of 3-methyl-isothiazolone and 10-20% by weight of sodium polyacrylate The 3-methyl-isothiazolone has a weight ratio of 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one in a ratio of 1: 1 to 1: 5. Mixed with The composition is diluted 0.1 to 1% by weight with water or an organic solvent selected from the group consisting of ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, 1,5-pentanediol and benzyl alcohol. One-component sterilization and anti-scaling agent composition, characterized in that. delete The method of claim 1, A one-part type disinfectant and anti-scaling agent composition, wherein the composition is administered once a week at a dose of 0.1 to 1 mg per liter of cooling water.