Circulating water corrosion and scale inhibitor as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of corrosion and scale inhibitors, and particularly relates to a circulating water corrosion and scale inhibitor and a preparation method and application thereof. The invention provides a circulating water corrosion and scale inhibitor, which is prepared from the following components in percentage by mass: 16 to 20 percent of 1, 2, 4-tricarboxylic acid-2-phosphonobutane, 16 to 20 percent of AA-AMPS-HPA terpolymer, 5 to 10 percent of zinc chloride, 0.6 to 1.0 percent of benzotriazole and the balance of water. Under the combined action of all the components in percentage by mass and under the conditions of high chloride ion content, high hardness and high alkali content, the scale and corrosion inhibitor has good effects of scale inhibition, corrosion inhibition and complexing in an open type circulating cooling water treatment system. The circulating water corrosion and scale inhibitor provided by the invention has relatively high corrosion and scale inhibition efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of scale inhibitors, and particularly relates to a circulating water corrosion and scale inhibitor, a preparation method thereof, and an application thereof. Background Art

[0002] Circulating water plays a crucial role in industrial production. However, the circulating water used has high strength and alkalinity and has serious scaling characteristics. In various situations where the water temperature is higher than the ambient temperature, the scaling of inorganic salts such as calcium carbonate will bring serious consequences. When used as a circulating medium in an industrial circulating water system, it will cause water quality deterioration and problems such as corrosion and scaling, resulting in blockage or leakage of heat exchanger equipment and its pipelines, seriously affecting the normal operation of production devices. At present, the phenomenon of scaling is mainly alleviated by adding scale inhibitors to the circulating water.

[0003] Existing circulating water corrosion and scale inhibitors are mainly used in open circulating cooling water treatment systems and are suitable for systems with a concentration ratio below 3 times. When the existing circulating water corrosion and scale inhibitors are used in systems with a concentration ratio above 4 times, the existing circulating water corrosion and scale inhibitors are prone to cause corrosion and scaling. Summary of the Invention

[0004] In view of this, the present invention provides a circulating water corrosion and scale inhibitor, a preparation method thereof, and an application thereof. The circulating water corrosion and scale inhibitor provided by the present invention has a high corrosion and scale inhibition efficiency under high-concentration multiple water quality.

[0005] To solve the above technical problems, the present invention provides a circulating water corrosion and scale inhibitor, comprising components in the following mass percentage contents:

[0006]

[0007] Preferably, it comprises components in the following mass percentage contents:

[0008]

[0009]

[0010] The present invention also provides a preparation method of the circulating water corrosion and scale inhibitor according to the above technical solution, comprising the following steps:

[0011] Mix 2-phosphonobutane-1,2,4-tricarboxylic acid, AA-AMPS-HPA terpolymer, zinc chloride, benzotriazole and water to obtain the circulating water corrosion and scale inhibitor.

[0012] Preferably, the mixing comprises the following steps:

[0013] First mix benzotriazole and 2-phosphonobutane-1,2,4-tricarboxylic acid to obtain a first solution;

[0014] Mix the first solution, AA-AMPS-HPA terpolymer, zinc chloride and water in sequence for the second time to obtain the circulating water corrosion and scale inhibitor.

[0015] The present invention also provides an application of the circulating water corrosion and scale inhibitor described in the above technical solution or the circulating water corrosion and scale inhibitor prepared by the preparation method described in the above technical solution in an open circulating cooling water treatment system.

[0016] The present invention provides a circulating water corrosion and scale inhibitor, which comprises the following components in mass percentage: 16-20% of 1,2,4-tricarboxylic acid-2-phosphonobutane, 16-20% of AA-AMPS-HPA terpolymer, 5-10% of zinc chloride, 0.6-1.0% of benzotriazole and the balance of water. The pH value of the operating environment of the corrosion and scale inhibitor of the present invention in circulating cooling water is between 8.0 and 9, and the calcium hardness (calculated as calcium carbonate) in the circulating cooling water can reach 900-1000 mg / L (the total alkalinity is 200-300 mg / L, and the content of chloride ions < 1000 mg / L). The scale inhibition rate of calcium carbonate of the corrosion and scale inhibitor provided by the present invention is greater than 97%, and the scale inhibition rate of calcium phosphate is greater than 97%; the corrosion rate of the corrosion and scale inhibitor provided by the present invention is carbon steel < 0.06 mm / a, naval brass < 0.004 mm / a, and stainless steel < 0.003 mm / a. The corrosion and scale inhibitor provided by the present invention has good scale inhibition effect, high corrosion inhibition rate and good use effect. Description of the Drawings

[0017] Figure 1 Schematic flow diagram for preparing the circulating water corrosion and scale inhibitor in the examples. Detailed Description of the Invention

[0018] The present invention provides a circulating water corrosion and scale inhibitor, which comprises the following components in mass percentage:

[0019]

[0020]

[0021] In the present invention, all raw materials are conventional commercially available products if not otherwise specified.

[0022] In the present invention, in terms of mass percentage, the circulating water corrosion and scale inhibitor comprises 16-20% of 1,2,4-tricarboxylic acid-2-phosphonobutane, preferably 17-19%, more preferably 18%. In the present invention, the 1,2,4-tricarboxylic acid-2-phosphonobutane (PBTCA) reacts with Ca 2+ , Zn 2+ , Cu 2+ , Mg 2+The plasma has excellent complexing ability, enabling the circulating water to operate under conditions of high temperature, high hardness, and high alkalinity, thereby avoiding the formation of water scale.

[0023] In the present invention, based on mass percentage, the circulating water corrosion and scale inhibitor comprises 16 - 20% of AA - AMPS - HPA terpolymer, preferably 17 - 19%, and more preferably 18%. In the present invention, the molecular chain of the AA - AMPS - HPA terpolymer contains strong acid, weak acid, and non - ionic groups simultaneously, and has a high calcium tolerance under conditions of high temperature, high pH value, high hardness, and high alkalinity. It has excellent inhibitory and dispersing properties against the deposition of dirt such as calcium carbonate, calcium phosphate, zinc scale, iron oxide, and sediment in water.

[0024] In the present invention, based on mass percentage, the circulating water corrosion and scale inhibitor comprises 5 - 10% of zinc chloride, preferably 6 - 8%. In the present invention, zinc chloride has the characteristics of dissolving metal oxides and cellulose.

[0025] In the present invention, based on mass percentage, the circulating water corrosion and scale inhibitor comprises 0.6 - 1.0% of benzotriazole, preferably 0.7 - 0.9%, and more preferably 0.8%. In the present invention, benzotriazole (BTA) can form covalent bonds and coordination bonds with metal atoms (copper, aluminum, cast iron, nickel, zinc) in the application equipment, forming multiple protective films on the surface of the metal, preventing the metal surface from undergoing oxidation - reduction reactions, and playing an anti - corrosion role.

[0026] In the present invention, based on mass percentage, the circulating water corrosion and scale inhibitor comprises the balance of water. In the present invention, the water is preferably distilled water.

[0027] Under the combined action of the components in the above - mentioned mass percentages in the present invention, under conditions of high chloride ion, high hardness, and high alkalinity, it plays a good role in scale inhibition, corrosion inhibition, and complexing in an open - type circulating cooling water treatment system. The circulating water corrosion and scale inhibitor provided by the present invention has a high corrosion and scale inhibition efficiency.

[0028] The present invention also provides a preparation method of the circulating water corrosion and scale inhibitor according to the above - mentioned technical solution, comprising the following steps:

[0029] Mix 2 - phosphonobutane - 1,2,4 - tricarboxylic acid, AA - AMPS - HPA terpolymer, zinc chloride, benzotriazole, and water to obtain the circulating water corrosion and scale inhibitor.

[0030] In the present invention, the mixing preferably comprises the following steps:

[0031] First, mix benzotriazole and 2 - phosphonobutane - 1,2,4 - tricarboxylic acid to obtain a first solution;

[0032] Mix the first solution, AA-AMPS-HPA terpolymer, zinc chloride and water in sequence for the second time to obtain the circulating water corrosion and scale inhibitor.

[0033] In the present invention, benzotriazole and 2-phosphonobutane-1,2,4-tricarboxylic acid are used to obtain the first solution. In the present invention, the first mixing is preferably carried out under stirring, the rotation speed of the stirring is preferably 50-150 r / min, more preferably 100-120 r / min; the stirring time is preferably 2-5 h, more preferably 3-4 h.

[0034] Mix the first solution, AA-AMPS-HPA terpolymer, zinc chloride and water in sequence for the second time to obtain the circulating water corrosion and scale inhibitor. In the present invention, the second mixing is preferably carried out under stirring, the rotation speed of the stirring is preferably 50-120 r / min, more preferably 80-100 r / min; the stirring time is preferably 2-4 h, more preferably 2.5-3.5 h.

[0035] Since benzotriazole is insoluble in water and soluble in organic components, in the present invention, benzotriazole is first dissolved in 2-phosphonobutane-1,2,4-tricarboxylic acid and then mixed with water, which can save the preparation time.

[0036] Figure 1 FIG. is a schematic process diagram for preparing the circulating water corrosion and scale inhibitor in the embodiment. Specifically, benzotriazole is added to the first mixer, and then 2-phosphonobutane-1,2,4-tricarboxylic acid is transported to the first mixer by a feed pump for stirring to obtain the first solution; the first solution is transported to the second mixer by a transfer pump, and at the same time, AA-AMPS-HPA terpolymer and water are transported to the second mixer by a feed pump, and zinc chloride is added to the second mixer for stirring to obtain the circulating water corrosion and scale inhibitor; the prepared circulating water corrosion and scale inhibitor is transported to a storage container by a discharge pump.

[0037] The present invention also provides the application of the circulating water corrosion and scale inhibitor described in the above technical solution or the circulating water corrosion and scale inhibitor prepared by the preparation method described in the above technical solution in an open recirculating cooling water system.

[0038] In order to further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0039] The present invention does not limit the weight of the raw material dosage in the embodiment, as long as the required mass percentage content can be achieved.

[0040] Example 1

[0041] Benzotriazole and 2-phosphonobutane-1,2,4-tricarboxylic acid were stirred at a rotation speed of 120 r / min for 3 h to obtain a first solution;

[0042] The first solution, AA-AMPS-HPA terpolymer, zinc chloride and distilled water were stirred in sequence at a rotation speed of 100 r / min for 4 h to obtain a circulating water corrosion and scale inhibitor; in the circulating water corrosion and scale inhibitor, the mass percentage content of 2-phosphonobutane-1,2,4-tricarboxylic acid is 20%, the mass percentage content of AA-AMPS-HPA terpolymer is 20%, the mass percentage content of zinc chloride is 5%, and the mass percentage content of benzotriazole is 0.6%.

[0043] Example 2

[0044] Benzotriazole and 2-phosphonobutane-1,2,4-tricarboxylic acid were stirred at a rotation speed of 120 r / min for 3 h to obtain a first solution;

[0045] The first solution, AA-AMPS-HPA terpolymer, zinc chloride and distilled water were stirred in sequence at a rotation speed of 100 r / min for 4 h to obtain a circulating water corrosion and scale inhibitor; in the circulating water corrosion and scale inhibitor, the mass percentage content of 2-phosphonobutane-1,2,4-tricarboxylic acid is 18%, the mass percentage content of AA-AMPS-HPA terpolymer is 18%, the mass percentage content of zinc chloride is 10%, and the mass percentage content of benzotriazole is 0.8%.

[0046] Comparative Example 1

[0047] A circulating water corrosion and scale inhibitor was prepared according to the method of Example 1, except that the mass percentage content of 2-phosphonobutane-1,2,4-tricarboxylic acid was 15%, the mass percentage content of AA-AMPS-HPA terpolymer was 22%, the mass percentage content of zinc chloride was 3%, and the mass percentage content of benzotriazole was 0.8%.

[0048] Comparative Example 2

[0049] A circulating water corrosion and scale inhibitor was prepared according to the method of Example 1, except that the mass percentage content of 2-phosphonobutane-1,2,4-tricarboxylic acid was 5%, the mass percentage content of AA-AMPS-HPA terpolymer was 30%, the mass percentage content of zinc chloride was 3%, and the mass percentage content of benzotriazole was 0.8%.

[0050] The scale and corrosion inhibitor prepared in Example 1 was used in the circulating water system of Inner Mongolia Yidong Group Jiuding Chemical Co., Ltd. The dosage was 40 ppm of the makeup water volume. The concentration multiple was 6.5 times, the pH value was 9.2, the calcium hardness (calculated as calcium carbonate) was 1000 mg / L, the total alkalinity was 300 mg / L, and the chloride ion content was 1100 mg / L. During the use process, the corrosion rates were as follows: for carbon steel: 0.05 mm / a; for naval brass: 0.003 mm / a; for stainless steel: less than 0.002 mm / a; and the scale inhibition rate was 97.2%.

[0051] The scale and corrosion inhibitor prepared in Example 2 was used in the laboratory in an environment with a pH value of 9.2, a calcium hardness (calculated as calcium carbonate) of 1200 mg / L, a total alkalinity of 300 mg / L, and a chloride ion content of 1200 mg / L. Through experiments (using the corrosion and scale inhibitor prepared in Example 2 of the present invention), static calcium carbonate scale inhibition, static calcium phosphate scale inhibition, and rotating coupon experiments were respectively carried out. The results were as follows: the calcium carbonate scale inhibition rate was 97%, the calcium phosphate scale inhibition rate was 97%; the corrosion rates were: for carbon steel: 0.03 mm / a, for naval brass: 0.0028 mm / a, for stainless steel: 0.0019 mm / a; and the scale inhibition rate was 96.5%.

[0052] The scale and corrosion inhibitor prepared in Comparative Example 1 was tested under the conditions of a pH value of 9.2, a calcium hardness (calculated as calcium carbonate) of 1000 mg / L, a total alkalinity of 300 mg / L, and a chloride ion content of 1100 mg / L. The measured corrosion rates were: for carbon steel: 0.053 mm / a; for naval brass: 0.0035 mm / a; for stainless steel: less than 0.003 mm / a; and the scale inhibition rate was 93.1%.

[0053] The scale and corrosion inhibitor prepared in Comparative Example 2 was tested under the conditions of a pH value of 9.2, a calcium hardness (calculated as calcium carbonate) of 1000 mg / L, a total alkalinity of 300 mg / L, and a chloride ion content of 1100 mg / L. The measured corrosion rates were: for carbon steel: 0.051 mm / a; for naval brass: 0.0026 mm / a; for stainless steel: 0.003 mm / a; and the scale inhibition rate was 86.5%.

[0054] It can be seen from the above test results that the scale and corrosion inhibitor provided by the present invention has good scale and corrosion inhibition performance.

[0055] Although the above embodiments have described the present invention in detail, they are only a part of the embodiments of the present invention, rather than all embodiments. People can also obtain other embodiments based on these embodiments without creative efforts, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A circulating water corrosion and scale inhibitor, characterized in that, Comprising components with the following mass percentages:

2. The circulating water corrosion and scale inhibitor according to claim 1, wherein Comprising components with the following mass percentages:

3. The preparation method of the circulating water corrosion and scale inhibitor according to claim 1 or 2, comprising the following steps: Mix 2-phosphonobutane-1,2,4-tricarboxylic acid, AA-AMPS-HPA terpolymer, zinc chloride, benzotriazole and water to obtain the circulating water corrosion and scale inhibitor.

4. The preparation method according to claim 3, characterized in that, The mixing comprises the following steps: First mix benzotriazole and 2-phosphonobutane-1,2,4-tricarboxylic acid to obtain a first solution; Second mix the first solution, AA-AMPS-HPA terpolymer, zinc chloride and water in sequence to obtain the circulating water corrosion and scale inhibitor.

5. The application of the circulating water corrosion and scale inhibitor according to claim 1 or 2 or the circulating water corrosion and scale inhibitor prepared by the preparation method according to any one of claims 3 to 4 in an open recirculating cooling water treatment system.

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