JP6156445B2 - Water-based microorganism control method - Google Patents

Description

  The present invention relates to a water-based microorganism control method.

  In plant cooling water systems, paper pulp water systems, wastewater treatment water systems, steel water systems, cutting oil water systems, etc. in various factories, slime composed of bacteria, filamentous fungi, algae, etc. is generated in the system, resulting in reduced thermal efficiency, water piping Cause slime troubles such as blockage of pipes and corrosion of pipe metal materials.

  Therefore, drugs for avoiding such slime disorders have been developed. Patent Document 1 discloses a slime release agent composed of a combination of a chlorine-based oxidizing agent and sulfamic acid or a salt thereof, and Patent Document 2 discloses an agent composed of a reaction product of ammonium bromide and sodium hypochlorite. It is disclosed.

JP 2003-267811 A Japanese Patent No. 3497171

  However, there is a need for a microbial control technique that is superior to conventional drugs. For example, the slime remover disclosed in Patent Document 1 has an excellent function of peeling the slime and cleaning the equipment surface, but has an insufficient bactericidal effect. Moreover, with the chemical | medical agent shown by patent document 2, once slime is formed, sufficient sterilization may be unable to be performed.

  The present invention has been made in view of the above circumstances, and is to provide a method capable of efficiently suppressing aqueous microorganisms.

  (1) In the water system of the papermaking facility, the present invention comprises adding one or more kinds of agents selected from a chlorine-based oxidizing agent and a combination of sulfamic acid or a salt thereof, or chlorosulfamic acid or a salt thereof, After adding the agent, 2,2-dibromo-2-nitroethanol, 4,5-dichloro-1,2-dithiolane-3-one, 2-bromo-2-nitro-1,3-propanediol, ortho Adding one or more slime control agents selected from phthalaldehyde, 2,2-dibromo-3-nitrilopropionamide, dichloroglyoxime, or a reaction product of ammonium salt and hypochlorite; This is an aqueous microorganism control method.

  (2) The present invention also relates to a chlorinated oxidant and a combination of sulfamic acid or a salt thereof, or one or more drugs selected from chlorosulfamic acid or a salt thereof, and 2,2-dibromo- 2-nitroethanol, 4,5-dichloro-1,2-dithiolane-3-one, 2-bromo-2-nitro-1,3-propanediol, orthophthalaldehyde, 2,2-dibromo-3-nitrilopropion In combination with one or more slime control agents selected from amide, dichloroglyoxime, or a reaction product of ammonium salt and hypochlorite, the above-mentioned agent is stored in a pulp system in the water system of a papermaking facility. It is a water-based microorganism control method comprising a step of adding the slime control agent to a papermaking system.

  (3) Moreover, this invention is a method as described in (1) or (2) in which the said slime control agent contains the reaction material of ammonium salt and hypochlorite.

  According to the present invention, a combination of a chlorine-based oxidizing agent and a sulfamic acid or a salt thereof, or an agent composed of chlorosulfamic acid or a salt thereof, and an inorganic or organic slime control agent, The microorganisms can be efficiently suppressed.

  Hereinafter, although embodiment of this invention is described, this invention is not limited to these.

  The water-based microorganism suppression method according to the present invention efficiently suppresses water-based microorganisms by using a predetermined drug and a slime control agent in combination.

  The slime control agent may be either inorganic or organic, and suppresses microorganisms in the aqueous system by exhibiting a bactericidal action. The slime control agent itself having such a function is conventionally known and can be widely used. Only one or both of the inorganic or organic slime control agents may be used.

  The inorganic slime control agent is not particularly limited, but 1 such as chloramine, bromamine, a reaction product of ammonium bromide and sodium hypochlorite, a reaction product of ammonium sulfate and hypochlorite, bromosulfamic acid, etc. It may be a seed or two or more. A reaction product of ammonium bromide and sodium hypochlorite is disclosed in Patent Document 2.

  The organic slime control agent is not particularly limited, but 2,2-dibromo-3-nitrilopropionamide (DBNPA), 2,2-dibromo-2-nitroethanol (DBNE), 2-bromo-2-nitro -1,3-propanediol (BNP), orthophthalaldehyde (OPA), glutaraldehyde, 4,5-dichloro-1,2-dithiolane-3-one (dithiol), 1,4-bis (bromoacetoxy)- 2-butene, 1,2-bis (bromoacetoxy) ethane, 2-methyl-4-isothiazolin-3-one or a metal salt thereof, 5-chloro-2-methyl-4-isothiazolin-3-one or a metal salt thereof 4,5-dichloro-2-octyl-4-isothiazolin-3-one, 1,2-benzisothiazolin-3-one, methyl Bisthiocyanate, hexabromodimethylsulfone, 3,3,4,4-tetrachlorotetrahydrothiophene-1,1-dioxide, dichloroglyoxime, 1-bromo-3-chloro-5,5-dimethylhydantoin, tetrakis-hydroxy 1 type, or 2 or more types, such as methyl- phosphonium sulfate, are mentioned.

  The inventors of the present invention are that the inorganic or organic slime control agent is excellent in bactericidal action, but once the slime (microbe floc) is formed, the microorganisms inside the slime cannot be sufficiently sterilized. Focused on. Therefore, in the present invention, a predetermined drug is used together with the slime control agent.

  The chemical | medical agent used by this invention consists of a chlorine-type oxidizing agent and the combination of sulfamic acid or its salt, or chlorosulfamic acid or its salt. These suppress the formation of slime and are excellent in the function of decomposing the adhesive component surrounding the microorganism in the slime even if the slime is formed. Thereby, since the combined slime control agent becomes easy to sterilize microorganisms, without being inhibited by the adhesion component, it is estimated that the efficiency of microorganism suppression improves. In addition, either the said combination and chlorosulfamic acid may be used, and both may be used.

  The combination of a chlorine-based oxidizing agent and sulfamic acid or a salt thereof may be disclosed in Patent Document 1. Specifically, the chlorine-based oxidant is not particularly limited as long as it is a chlorine-based oxidant. From the viewpoint of cost, handleability, safety, solubility in water, and the like, hypochlorous acid or a salt thereof is preferable. Sodium hypochlorite is preferable. As sodium hypochlorite, 12% sodium hypochlorite which is generally available can be used.

  The sulfamic acid or a salt thereof is not particularly limited, and may be, for example, sulfamic acid, ammonium sulfamate, or the like. Sulfamic acid is not toxic like hydrazine and is highly safe.

  The effective chlorine content of the chlorinated oxidant and the content ratio of the sulfamic acid and its salt are in the molar ratio (effective chlorinated oxidant) :( sulfamic acid and its salt) from 2: 1 to 1: 5, preferably It is desirable that the ratio is 2: 1 to 1: 2. The effective chlorine of the chlorinated oxidant is chlorine measured by a residual chlorine measuring method based on JIS K0101.

  It is preferable that alkalis, such as sodium hydroxide and potassium hydroxide, are also contained in the said combination from a viewpoint of improving storage stability more.

  Chlorosulfamic acid or a salt thereof is not particularly limited, and may be one or more of N-chlorosulfamic acid, N, N-dichlorosulfamic acid, or one or more salts thereof.

  From the above functions of the drug and the slime control agent, the drug is preferably added simultaneously with or before the addition of the slime control agent. Thereby, since suppression of slime formation or decomposition | disassembly of an adhesive substance is made | formed previously, the bactericidal action of a slime control agent is easy to be show | played quickly. However, the addition of the drug may be after the addition of the slime control agent.

  Before, simultaneously with, and after addition is not limited to time, but also includes place. For example, if the addition of the drug is performed before the addition of the slime control, the addition of the slime control is not limited to the (time) mode in which the addition of the slime control is started after the start of the addition of the drug. In addition, a (spatial) embodiment that is upstream of the water system is also included.

  The addition part of a chemical | medical agent and a slime control agent is not specifically limited. But it is preferable that the method of this invention has the process of adding a chemical | medical agent and a slime control agent in the location where the slime disorder | damage | failure was detected. Thereby, a slime failure can be eliminated directly and efficiently. In the conventional method, even if a formulation is added to a place where slime damage has occurred, it is difficult to remove the damage efficiently due to inhibition by the slime. is there. In addition, what is necessary is just to perform the detection of a slime failure along a conventional method.

  When a place where a slime disorder is likely to occur can be identified, it is preferable to add a drug to a place where the slime disorder is likely to occur or upstream thereof, and to add a slime control agent to a place where the slime disorder is likely to occur. Thereby, slime failure can be prevented efficiently.

  The method of the present invention preferably includes a step of adding a chemical to the pulp storage unit and adding a slime control agent to the papermaking system in the water system of the papermaking facility. The pulp reservoir is in a eutrophic state, and slime is likely to be formed. However, the addition of a chemical to the pulp storage part suppresses slime formation and reduces the inflow of slime downstream (including the papermaking system). As a result, the papermaking slime control agent acts effectively and can suppress microorganisms. In addition, the addition part of the chemical | medical agent and slime control agent in the water system of papermaking facilities is not restricted to this.

  The addition amount of a chemical | medical agent and a slime control agent is not specifically limited, Each may be 0.2-500 mg / L. The addition ratio of the drug to the slime control agent is not particularly limited, and may be 99/1 to 5/95 (mass ratio). Moreover, you may change the addition amount suitably according to conditions, such as a grade of a slime disorder | damage | failure. For example, when the degree of slime injury is increased, even if the addition amount or ratio of the slime control agent is increased, the bactericidal action is not efficiently achieved, so control for increasing the addition amount or ratio of the drug may be performed. The addition amount ratio refers to the ratio of the addition amount within a certain time.

  The method of adding the drug and the slime control agent is not particularly limited, and may be added separately or after mixing. The addition of at least one of the drug and the slime control agent may be performed continuously or intermittently. In addition, it is preferable that a chemical | medical agent and a slime control agent are the form of the solution (for example, aqueous solution) by which the density | concentration preparation was carried out from a quantitative viewpoint.

  The water system to which the method of the present invention is applied is not particularly limited as long as it can cause damage by microorganisms, such as plant cooling water system of various factories, paper pulp water system, waste water treatment water system, steel water system, cutting oil water system, etc. It may be.

  In the method of the present invention, if necessary, a biocide, a growth inhibitor, a corrosion inhibitor, a copper anticorrosive, a scale inhibitor, an antifoaming agent, a surfactant and the like may be further used.

<Example 1>
A polyvinyl chloride tube having an inner diameter of 3 mm was passed through a constant temperature water bath at 35 ° C., and the medium was passed through the tube at an amount of 8 mL / min. 2 g of glucose, 0.35 g of ammonium sulfate, 0.7 g of dipotassium hydrogen phosphate, 0.3 g of potassium dihydrogen phosphate and 0.05 g of magnesium sulfate heptahydrate were dissolved in 10 L of dechlorinated tap water. To this solution, 100 mL of a 0.5 M phosphate buffer solution having a pH of 7 and cultured as a fungus was coated white paper water in a standard medium and inoculated so that the number of bacteria was 10 ⁶ / mL or more. . A Y-tube was provided in the middle of the tube so that the preparation shown in Table 1 could be added, and the preparation was added in a cycle of addition for 4 hours and rest for 4 hours.

  Seven days later, the tube was taken out and split, and the slime adhering to the 10 cm length of the tube was wiped off with a cotton swab and dispersed in 1 mL of sterilized water, and the amount of ATP in the dispersion was measured. The results are shown in Table 1. It is known that the amount of ATP is proportional to the number of bacteria.

ＣＳＡ：クロロスルファミン酸
ＤＢＮＥ：２,２−ジブロモ−２−ニトロエタノール
ジチオール:４,５−ジクロロ−１,２−ジチオラン−３−オン
ＯＰＡ:オルトフタルアルデヒド

CSA: chlorosulfamic acid DBNE: 2,2-dibromo-2-nitroethanol dithiol: 4,5-dichloro-1,2-dithiolan-3-one OPA: orthophthalaldehyde

  As shown in Table 1, in Examples 1 to 3 in which chlorosulfamic acid and a slime control agent were used in combination, the amount of ATP, that is, the fungus, was lower compared to the comparative example using only one of them, although the total amount added was low. It was found that the number could be remarkably reduced and slime adhesion was effectively suppressed.

<Example 2>
A pink slime-causing bacterium, Methylobacterium sp., Isolated from a pink slime generated in a machine for making a coated base paper (a pink-colored slime that produces pink spots when transferred to paper). (Methylobacterium species) was cultured in a standard liquid medium at 30 ° C. for 2 days to obtain a pink microbial floc. The floc was washed with sterilized water and crushed with a stirrer to obtain a fine floc. This fine floc was dispersed in a 1 / 150M phosphate buffer having a pH of 7 to obtain a test solution. The formulations shown in Table 2 were added to this test solution, and after shaking at 30 ° C. for 2 hours, 200 mg / L of sulfurous acid was immediately added to decompose the formulation. Thereafter, the test solution was placed in a sterilized homogenizer and treated at 10,000 rpm for 3 minutes to disperse the cells. Table 2 shows the results of measuring the number of dispersed cells by the agar plate dilution method.

ＤＢＮＰＡ:２,２−ジブロモ−３−ニトリロプロピオンアミド
反応物Ａ:臭化アンモニウム水溶液と次亜塩素酸ナトリウム水溶液とを混合したもの
ＤＣＧ:ジクロログリオキシム

DBNPA: 2,2-dibromo-3-nitrilopropionamide Reaction product A: A mixture of aqueous ammonium bromide solution and aqueous sodium hypochlorite solution DCG: dichloroglyoxime

  As shown in Table 2, in the examples in which chlorosulfamic acid was used in combination with the slime control agent, the number of bacteria could be remarkably reduced and sterilization could be efficiently performed compared to the comparative example using only one of them. I understood.

<Example 3>
In a machine that forms a coated base paper by blending virgin pulp (LBKP) and deinked pulp (DIP), slime damage due to decay of the deinked pulp was significant. Therefore, a reaction product of an aqueous solution of ammonium bromide and an aqueous solution of sodium hypochlorite was added to the deinked pulp chest at 2 mg / L (as Cl2 vs. retained water) 8 times / day, and 2 mg / L (as Cl2) in the papermaking system. ) And added 3 times / day to hold for 10 minutes. Then, although improvement was seen after the start of addition, slime began to adhere to the white water silo after 2 weeks, and after 3 weeks, spots that seemed to be caused by slime began to appear on the paper.

  Next, in the deinked pulp chest, the reaction product of sodium sulfamate and sodium hypochlorite is 2 mg / L (as Cl2 vs. retained water) 4 times / day, and ammonium bromide and hypochlorous acid are used in the papermaking system. The reaction with aqueous sodium was added 3 times / day, respectively, to hold at 2 mg / L (as Cl2) for 10 minutes. Then, slime generation in the white water silo was suppressed for over 3 weeks, and the occurrence of speckles on the paper was greatly reduced.

  It should be noted that the reaction product of sodium sulfamate and sodium hypochlorite was held 3 times so that the deinked pulp was maintained at 2 mg / L (as Cl2 vs. retained water) and at 5 mg / L (as Cl2) for 30 minutes in the papermaking system. Even after each addition, slime began to adhere after 2 weeks.

  As a result, in the water system of papermaking equipment, a combination of sodium sulfamate and sodium hypochlorite is added to the pulp reservoir, and the slime control agent is added to the papermaking system, so that even if the total amount added is small, it can be efficiently It turns out that slime can be controlled.

<Example 4>
In a system in which oxidized starch is gelatinized and applied as a surface sizing agent, BNP is continuously added to the paste liquid after gelatinization in an amount of 20 mg / L, and BNP is added to the circulating system to be applied at 50 mg / L (vs. Inflow paste amount) was added for 2 hours and 3 times. However, after 5 days, rot progressed, the pH dropped from 6.5 to 5.5, and foaming by the rot product began. Therefore, instead of BNP added to the circulatory system, chlorosulfamic acid was added 3 times for 4 hours at 5 mg / L (the amount of inflow paste), and the pH gradually increased until 6.5 days later. It recovered and the foam was settled.

  Thus, it was found that by using chlorosulfamic acid in combination with a slime control agent, an antiseptic effect can be obtained efficiently even though the total amount added is low. This is because chlorosulfamic acid acts on slime adhering to the system and decomposes the extracellular polymer (adhesive component). As a result, the added slime control agent acts directly on the fungus and exerts an antiseptic effect. This is probably due to the fact that

Claims (2)

In the water system of papermaking equipment,
Adding one or more agents selected from a chlorine-based oxidizing agent and a combination of sulfamic acid or a salt thereof, or chlorosulfamic acid or a salt thereof;
After adding the agent, 2,2-dibromo-2-nitroethanol, 4,5-dichloro-1,2-dithiolane-3-one, 2-bromo-2-nitro-1,3-propanediol, ortho 1 selected from phthalaldehyde, 2,2-dibromo-3-nitrilopropionamide, dichloroglyoxime, a reaction product of ammonium bromide and hypochlorite, or a reaction product of ammonium sulfate and hypochlorite added species or two or more of slime control agent,
An aqueous microorganism control method , wherein the slime control agent contains a reaction product of ammonium bromide and hypochlorite, or a reaction product of ammonium sulfate and hypochlorite . One or more drugs selected from a combination of a chlorine-based oxidizing agent and sulfamic acid or a salt thereof, or chlorosulfamic acid or a salt thereof;
2,2-dibromo-2-nitroethanol, 4,5-dichloro-1,2-dithiolane-3-one, 2-bromo-2-nitro-1,3-propanediol, orthophthalaldehyde, 2,2- One or more slimes selected from dibromo-3-nitrilopropionamide, dichloroglyoxime, a reaction product of ammonium bromide and hypochlorite, or a reaction product of ammonium sulfate and hypochlorite In combination with a control agent,
In aqueous paper making plant, said agent is added to the pulp storage section, have a step of adding the slime control agent in paper making system,
An aqueous microorganism control method , wherein the slime control agent contains a reaction product of ammonium bromide and hypochlorite, or a reaction product of ammonium sulfate and hypochlorite .