Classifications

• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
  • C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
  • C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
  • C02F5/14—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing phosphorus
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N43/00—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds
  • A01N43/72—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with nitrogen atoms and oxygen or sulfur atoms as ring hetero atoms
  • A01N43/80—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with nitrogen atoms and oxygen or sulfur atoms as ring hetero atoms five-membered rings with one nitrogen atom and either one oxygen atom or one sulfur atom in positions 1,2
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N57/00—Biocides, pest repellants or attractants, or plant growth regulators containing organic phosphorus compounds
  • A01N57/18—Biocides, pest repellants or attractants, or plant growth regulators containing organic phosphorus compounds having phosphorus-to-carbon bonds
  • A01N57/20—Biocides, pest repellants or attractants, or plant growth regulators containing organic phosphorus compounds having phosphorus-to-carbon bonds containing acyclic or cycloaliphatic radicals
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
  • A01N59/16—Heavy metals; Compounds thereof
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
  • A01N59/26—Phosphorus; Compounds thereof
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/50—Treatment of water, waste water, or sewage by addition or application of a germicide or by oligodynamic treatment
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2303/00—Specific treatment goals
  • C02F2303/04—Disinfection
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W10/00—Technologies for wastewater treatment
  • Y02W10/30—Wastewater or sewage treatment systems using renewable energies
  • Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy

Definitions

• the present invention relates to a multifunctional water-treating composition and method of water treating using the same. More particularly, the present invention relates to a water-treating composition which has superior stability during storage or use thereof, as well as is capable of suppressing a corrosion, a scale formation and a growth of microorganisms simultaneously, which take place in an open-circulation cooling water system.
• the temperature of cooling water is controlled with equipment that is called a cooling tower. Since air always flows into the water-temperature controlling system having the cooling tower, the system is called as the open-circulation cooling water system.
• various minerals contained in water are concentrated due to the water-evaporation.
• various phenomena that influence the cooling operation take place. These phenomena are largely classified into problems of corrosion, a scale formation and microorganisms.
• the corrosion means a rust formation on a metal material.
• metal is made by refining an oxidized substance, so it has a strong property to return to the oxidized state that is a thermodynamically stable state. Therefore, it is natural that the corrosion may occur in the open-circulation cooling water system.
• the scale is formed by sediments resulted from the metal corrosion, or by combination of various divalent metal ions in the water with negative ion compounds. As the temperature of the cooling water increases, solubility of metal salt decreases. Thus, the scale is easily formed on a place in the state of a comparatively high temperature due to heat, for example, a freezer or a heat exchanger of the open-circulation cooling water system. If the scale is excessively formed, a pipe may get clogged up and heat transfer efficiency becomes low, which result in the undue energy loss.
• Microorganisms such as bacteria, fungi, moss etc can grow well or not according to environmental conditions.
• the environments of the cooling tower including a water temperature, pH, dissolved oxygen content, mineral contents, and sunlight provide very suitable conditions for the growth of microorganisms. If microorganisms, which grow in such a suitable environment, were coagulated each other and were stuck to fillers in the cooling tower, they interfere the flow of water and air, which results in the decrease of the cooling efficiency.
• Microorganism sludge adhered to the filler in the cooling tower is called a slime. If such slime was adhered to a surface of metal pipe, the partial corrosion due to the microorganism may occur.
• the conventional water- treating method uses a corrosion inhibitor, a scale inhibitor, and a microorganism inhibitor separately for the water-treatment.
• a conventional water-treating method suppressed the scale formation by introducing a scale inhibitor, and then suppressed the growth of microorganisms by introducing a microorganism inhibitor.
• a water-treating composition including azole compound and phosphate salt was disclosed in U.S. Pat. No. 4,134,959. Also, U.S.
• Pat. No. 5,227,133 disclosed a cooling water-treatment method using a composition containing zinc salt, molybdenum salt and phosphate salt
• U.S. Pat. No. 5,156,665 disclosed a method for preventing a growth of the microorganism.
• the water-treating composition for preventing corrosion and scale formation is less effective in preventing the growth of microorganisms, and the water-treating composition for preventing the growth of microorganisms is less effective in preventing the corrosion and scale formation. Therefore, the use of the conventional water-treating composition is restrictive, and a user must inject suitable water-treating compositions according to a water condition.
• the reason that the corrosion inhibitor, the scale inhibitor and the microorganism inhibitor each is developed respectively is because, if they all are mixed to form a composition, the stability of the product is deteriorated, and precipitates are formed due to a lack of compatibility between the respective components. In addition, the possible effects derived from the respective components cannot be performed sufficiently.
• the present inventors have developed a water-treating composition, which has a superior, stability during storage or use thereof, and is capable of solving the problems related to corrosion, a scale formation, and a growth of microorganisms simultaneously in an open-circulation cooling water
• an object of the present invention is to provide a water- treating composition for a cooling tower which is capable of simultaneously suppressing a corrosion, a scale formation and microorganism growth, and is easy to use, and a method of water-treating using the same, with compared to the conventional a water-treating composition.
• Another object of the present invention is to provide a water-treating composition which has superior compatibility between the respective components of the composition, and has superior stability during storage or use of the composition product, and a method of water-treating using the same.
• a uniform multifunctional water-treating composition comprising at least one component selected from a group consisting of a mixture including azole compound and carboxylate, orthophosphate salt and zinc salt, a microorganism growth inhibitor, a scale formation inhibitor, an organic phosphonate and nitrate.
• a mixture including azole compound and carboxylate, orthophosphate salt and zinc salt a microorganism growth inhibitor, a scale formation inhibitor, an organic phosphonate and nitrate.
• 3- isothiazolinone can be used as the microorganism growth inhibitor
• acrylate polymer can be used as the scale formation inhibitor.
• the amount of the microorganism growth inhibitor is from 0.05 to 15% by weight
• the amount of the scale formation inhibitor is from 0.5 to 50% by weight
• the amount of the above organic phosphonate is from 0.2 to 30% by weight, wherein the amount is the amount of organic phosphonate ion
• amount of the nitrate is from 0.02 to 20% by weight, wherein the amount is the amount of nitrate ion.
• the preferred amount of orthophosphate and/or zinc salt is from 0.1 to 30% by weight, wherein the amount is the total amount of orthophosphate ion and zinc ion. If the mixture including azole compound and carboxylate is used, the preferred amount of azole compound is from 0.01 to 10% by weight, and amount of carboxylate is from 0.2 to
• the present invention also provides a water-treating method for preventing a corrosion, a scale formation and a growth of microorganisms, the method including a step of introducing a multifunctional water-treating composition comprising at least one component selected from a group consisting of mixture including azole compound and carboxylate, orthophosphate salt and zinc salt, a microorganism growth inhibitor, a scale formation inhibitor, an organic phosphonate and nitrate into a cooling water system.
• a multifunctional water-treating composition comprising at least one component selected from a group consisting of mixture including azole compound and carboxylate, orthophosphate salt and zinc salt, a microorganism growth inhibitor, a scale formation inhibitor, an organic phosphonate and nitrate into a cooling water system.
• the conventional inhibitors of the microorganism growth may be used.
• 3-isothiazolinone of the following Chemical Formula 1 is preferable as the inhibitor of the microorganism growth due to the superior compatibility of 3-isothiazolinone with another compounds such as the inhibitor of scale formation, organic phosphonate, azole compound, carboxylate, orthophosphate salt and zinc salt, superior growth suppressing effect on various microorganisms, and longtime-continuing inhibiting property.
• R 0 represents hydrogen or chloride. Specifically, it is more preferred that 2-methyl-4-isothiazolone-3-one in which Ro is a hydrogen in the chemical formula 1 , or 5-chIoro-2-methyl-4- isothiazolone-3-one in which R 0 is a chloride in the chemical formula 1 is used. It is most preferred that mixture of 2-methyl-4-isothiazolone-3-one and 5-chloro-2- methyl-4-isothiazolone-3-one with the mix ratio of 1 :20 to 20:1 by weight is used.
• the amount of 3- isothiazolinone of chemical formula 1 is preferably 0.05 to 15% by weight in the total amount of the water-treating composition. If the amount of 3-isothiazolinone is less than 0.05% by weight, the sterilization effect is lowered, and if the amount of 3-isothiazolinone is more than 15% by weight, the sterilization effect improves, but the composition is not economical.
• the conventional inhibitor of the scale formation may be used.
• acrylate polymer of the following Chemical Formula 2 is preferable as the inhibitor of the scale formation due to the superior compatibility of acrylate polymer with another compounds such as the inhibitor of microorganism growth, organic phosphonate, azole compound, carboxylate, orthophosphate salt and zinc salt, and superior preventing effect of scale formation due to divalent metal salts.
• R represents a hydrogen, a methyl or a carboxyl group, and when R is a carboxyl group, it can be combined with neighboring carbonyl groups to form an anhydrous ring.
• Ri and Re which can be same or different, each represents a hydrogen, an alkyl group, a hydroxyl group or a phosphono group.
• R 2 and R 3 which can be same or different, each represents a hydrogen or an alkyl group of C1-C2.
• R 4 represents a hydrogen, an alkyl group of C1-C5, and
• R 5 represents an alkyl group of C1-C8 or an aralkyl group of C8-C10.
• X and Y which can be same or different, each represents a hydrogen, an alkyl group of C1- C5 or a hydroxyalkyl group of C1-C5.
• R 0 includes one or more group selected from the following chemical formulas 3, 4 and 5. [Chemical formula 3]
• R 6 and R ⁇ 2 which can be same or different, each represents a hydrogen or an alkyl group of C1-C2, and R 13 and R-
• R 7 represents an alkyl group of C1-C6, an aralkyl group of C6-C10 or a group of the following chemical formula 6.
• i is 1 ,2 or 3
• R g represents a hydrogen or an alkyl group of C1-C2
• R-io represents a hydrogen or an alkyl group of C1-C6.
• the amount of acrylate polymer in the water-treating composition of the present invention is 0.5 to 50% by weight. If the amount of acrylate polymer is less than 0.5% by weight, inhibition ability of the scale formation is lowered, and if the amount of acrylate polymer is more than 50% by weight, the inhibition ability of the scale improves, but the composition is not economical.
• the water-treating composition of the present invention further includes at least one component selected from a group consisting of mixture including azole compound and carboxylate, orthophosphate salt and zinc salt.
• the azole compound benzotriazole, tolyltriazole, mercaptobenzothiazole or mixtures thereof is preferably used, and benzotriazole is more preferably used.
• carboxylate carboxylate compounds having carbon numbers of 3 to 12 or mixtures thereof is preferably used, and citrate is more preferably used.
• the amount of azole compound in the water- treating composition is 0.01 to 10% by weight, and more preferably 0.05 to 8% by weight. If amount of azole compound is less than 0.01 % by weight, a prevention of the corrosion could not be performed efficiently, and if amount of azole compound is more than 10% by weight, it is economically inefficient.
• the amount of carboxylate is 0.2 to 40% by weight, wherein the amount is the amount of the carboxylate compound, and more preferably 0.5 to 30% by weight. If amount of the carboxylate compound is less than 0.2% by weight, a prevention of the corrosion could not be performed efficiently, and if amount of carboxylate compound is more than 40% by weight, it is economically inefficient.
• orthophosphate As orthophosphate, orthophosphate mono basic, orthophosphate di basic, orthophosphate tri basic, phosphoric acid, or mixtures thereof is preferably used, and phosphoric acid is more preferably used.
• zinc salt zinc chloride, zinc sulfate, zinc nitrate, or mixtures thereof is preferably used.
• the amount of orthophosphate salt and/or zinc salt in the water-treating composition is
• the amount is the total amount of the respective ion, namely, the total amount of orthophosphate ion and zinc ion. More preferably, the amount of the zinc ion is 0.1 to 20% by weight, and the amount of the orthophosphate ion is 0.5 to 30% by weight. If amount of zinc ion is less than 0.1 % by weight, a prevention of the corrosion could not be performed efficiently, and if amount of zinc ion is more than 20% by weight, it will cause bad influence to fish and shellfishes when discarded as sewage. If amount of the orthophosphate ion is less than 0.5% by weight, a prevention of the corrosion could not be performed efficiently, and if amount of orthophosphate ion is more than 30% by weight, it will cause the scale of calcium phosphate.
• organic phosphonate of the present invention hydroxyethylidene diphosphonic acid, hydroxyphosphono carboxylic acid, aminotrimethylene phosphonic acid, phosphonobuthane tricarboxylic acid, ethylenediamine tetramethylidene phosphonic acid or mixtures thereof is preferably used.
• the amount of organic phosphonate in the water-treating composition is 0.2 to 30%) by weight, wherein the amount is the amount of the organic phosphonate ion.
• amount of the organic phosphonate ion is less than 0.2 wt%, prevention of the corrosion and scale formation could not be performed efficiently, and if amount of the organic phosphonate ion is more than 30 wt%, it is economically inefficient.
• Nitrate used in the present invention improves the compatibilities between the inhibitor of microorganism growth, the inhibitor of scale formation, organic phosphonate, azole compound, and carboxylate, and also improves the storage stability.
• the nitrate magnesium nitrate, copper nitrate, etc can be used.
• the amount of the nitrate in the water-treating composition of the present invention is 0.02 to 20% by weight, wherein the amount is the amount of the nitrate ion. If amount of the nitrate ion is less than 0.02% by weight, the anticorrosive ability and storage stability of product is deteriorated, and if amount of the nitrate ion is more than 20% by weight, it is economically inefficient.
• the water-treating composition of the present invention is preferably introduced into the cooling water so that the concentration of the composition is from 1 ppm to 500 . 000ppm.
• the water-treating composition of the present invention is effectively used to inhibit the scale formation and the corrosion, which can be occurred in various industrial water flowing pipes such as cooling tower and heat exchanger. Therefore, the water-treating composition of the present invention is preferably used for the open-circulation cooling water system or the various water flowing cooling system.
• the water-treating composition of the present invention is more preferably used for the open- circulation cooling water system in which the corrosion and the growth of the microorganism induce more serious problems.
• Example 1-3 and Comparative example 1-3 The water treating compositions including azole compound, carboxylate, orthophosphate salt, zinc salt, acrylate copolymer, organic phosphonate, isothiazolinone, or nitrate were dissolved into water so that the amounts of the effective ingredients in the test water-samples are as shown in Tables 1 and 2 (Examples 1-9) and Tables 3 and 4 (Comparative examples 1-6). The tests for inhibiting the corrosion, the scale formation, the microorganism growth were conducted.
• the organic phosphonate represents hydroxyethylidene diphosphonic acid [HEDP of LONZA Co., Ltd.], and the acrylate polymer is Belclenece 400 (product of FMC Co., Ltd), and the isothiazolinone is SKYBIO WG(product of SK chemical Co., Ltd).
• the used azole compounds is benzotriazole, and the used carboxylate is citric acid.
• the salts to produce orthophosphate, zinc, and nitrate ion phosphoric acid, zinc chloride, and magnesium nitrate are used respectively.
• Carbon steel test specimen was rotated at a rotation speed of 170 rpm, air- injection condition of 10CC/min, and temperature of 30 ° C, in order to determine the corrosion rate of the carbon steel.
• concentrations of the components of water-treating compositions of the present invention shown in Tables 1 and 2, and the concentrations of the components of conventional water-treating compositions shown in Table 3 and 4 are maintained in water samples having the properties shown in the following Table 5.
• the carbon steel was digested for five days. The corrosion rate [mdd, mg/(dm 2 • day)] based upon weight loss of the carbon steel was determined and the results were shown in Table 6.
• the pH of the water sample was adjusted with 0.1 N sodium hydroxide aqueous solution and 0.05N sulfuric acid aqueous solution.
• the calcium hardness, the M-alkalinity, the magnesium hardness and amount of the chlorine ion were adjusted with calcium chloride, sodium bicarbonate, magnesium sulfate and sodium chloride, respectively.
• the total hardness represents the sum of the calcium hardness and the magnesium hardness.
• the corrosion preventing abilities of compositions of Examples 1 to 3 are much superior to them of Comparative examples 1-3.
• the corrosion preventing abilities of compositions of Examples 4 to 9 are much superior to them of Comparative examples 4-6 which are including orthophosphate, zinc salt or organic phosphonate, separately.
• the uniform multifunctional water-treating composition of the present invention is stable in the mixed state and has superior corrosion preventing property.
• Test solution was tightly sealed up, and was reserved for 24 hours at 75 ° C .
• the test solution was filtered with 0,45 ⁇ s_ ⁇ filter, then scale inhibitor efficiency was determined by measuring the total hardness.
• concentrations of the components of water-treating compositions of the present invention shown in Tables 1 and 2, and the concentrations of the components of conventional water- treating compositions shown in Table 3 and 4 are maintained in water samples having the properties shown in the following Table 7.
• the Ct represents total hardness of water sample before the test
• the Ce represents total hardness of water sample after the test.
• the solutions including 8 species microorganisms (8 species of Enterobacter aerogens ATCC 13048, Escherichia coli ATCC 11229, Micrococcus luteus ATCC 9341 , Pseudomonas aeruginosa ATCC 15442, Klebsiella pneumoniae ATCC 1560, Staphylococcus edidermis ATCC, Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6984) were introduced into samples under the conditions of 30 ° C , 170rpm, and air-injection condition of 10ml/min. After two days, concentration reductions of microorganisms were measured. At this time, the microorganism solutions were produced to the concentration of 10 6 CFU/ml, and introduced into the water sample having the properties shown in
• the water-treating composition for the open-circulation cooling water system simultaneously improves the functions of preventing metal corrosion, scale formation and microorganism growth, and has the superior stability during storage or use thereof.
• the water-treating composition of present invention has longtime- continuing sterilizing power, and its sterilization effect for all microorganisms is very effective in the open-circulation cooling water system.
• the composition can prevent both of the anode reaction and the cathode reaction of the corrosion reactions. Therefore, the composition effectively reduces the corrosion, which can occur on metal surface.
• the acrylate copolymer and organic phosphonate modify the crystalline structure of the scale of the divalent metal salt, and thus effectively prevent the scale formation.
• the water-treating composition according to the present invention simultaneously improves the functions of preventing metal corrosion, scale formation and microorganism growth.

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