Novel corrosion and scale inhibitor for closed circulating water

Abstract

The invention discloses a novel corrosion and scale inhibitor for closed circulating water, and belongs to the field of cooling water treatment. The specific synthesis method comprises the following steps: adding a terpolymer, tungstate and azoles into pure water, and mixing to obtain the novel corrosion and scale inhibitor for closed circulating water. The terpolymer is an acrylic acid-2-acrylamide-2-methyl propane sulfonic acid copolymer; tungstate is at least one of sodium tungstate and potassium tungstate; the azole is at least one of benzotriazole, mercaptobenzothiazole and methyl benzotriazole; the novel corrosion and scale inhibitor for the closed circulating water does not contain toxic heavy metals and phosphorus components, so that the ecological environment is protected, and the environmental protection requirement is met; the corrosion inhibitor has good corrosion inhibition performance, can effectively control water quality and prevent equipment such as carbon steel in a closed circulating water system from being corroded and deposited with scales, and the corrosion rate of the carbon steel can be lower than 0.005 (mm / a).

Description

Technical Field

[0001] The invention belongs to the field of cooling water treatment, and in particular relates to a novel corrosion and scale inhibitor for closed circulating water. Background Art

[0002] Closed circulating water systems require the addition of corrosion and scale inhibitors to prevent corrosion and scaling, thereby improving system efficiency and extending equipment life. At present, some corrosion and scale inhibitors have poor treatment effects in closed circulating water systems; some commonly used corrosion and scale inhibitors for closed circulating water include chromates, phosphates, and organic phosphoric acids. Phosphorus-containing corrosion inhibitors such as phosphates, polyphosphates, and organic phosphoric acids have certain limitations. Phosphorus compounds will increase the phosphorus content in water, which is subject to national restrictions on the allowable phosphorus emission concentration, and are prone to algae growth. Chromates are mainly used in closed circulating cooling water systems. They can form a continuous and dense passivation film on the surface of steel, which can provide good protection not only for steel, but also for copper, zinc, aluminum and their alloys. However, their use is highly toxic, accumulates in the environment or in animals and plants, and has long-term adverse effects on human health. Moreover, their use is difficult to meet the requirements of modern industry for environmental protection and health. Therefore, the prior art urgently needs a corrosion and scale inhibitor that can effectively prevent corrosion and scaling, is widely used, and meets modern environmental protection requirements. Summary of the invention

[0003] The purpose of the present invention is to provide a novel corrosion and scale inhibitor for closed circulating water to solve the problems of poor corrosion and scale inhibition effect and unsafe and environmentally unfriendly corrosion and scale inhibition of the corrosion and scale inhibitor.

[0004] In order to solve the above technical problems, the present invention specifically provides the following technical solutions: The invention discloses a method for preparing a novel corrosion and scale inhibitor for closed circulating water, comprising: adding a terpolymer, tungstate and azoles to a solvent and mixing to obtain the novel corrosion and scale inhibitor for closed circulating water; the mass fraction of the tungstate in the novel corrosion and scale inhibitor for closed circulating water is 10-25%. The combined use of tungstate, terpolymer and azoles can produce a good anti-corrosion film on the metal surface in the closed circulating water system, hinder the hydration reaction of metal ions and the reduction reaction of dissolved oxygen, provide good protection for metals, inhibit corrosion reactions, thereby reducing the corrosion rate of metals, and have good performance and effects.

[0005] Preferably, the terpolymer is acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer.

[0006] Preferably, the mass fraction of the terpolymer in the novel corrosion and scale inhibitor for closed circulating water is 10-25%.

[0007] Preferably, the tungstate is at least one of sodium tungstate and potassium tungstate.

[0008] Preferably, the azole is at least one of benzotriazole, mercaptobenzothiazole and tolutriazole.

[0009] Preferably, the mass fraction of azoles in the new corrosion and scale inhibitor for closed circulating water is 1-3%.

[0010] Preferably, the solvent is water.

[0011] Preferably, the mass fraction of the solvent in the novel corrosion and scale inhibitor for closed circulating water is 47-79%.

[0012] The invention discloses a novel corrosion and scale inhibitor for closed circulating water, comprising the novel corrosion and scale inhibitor for closed circulating water prepared by the method.

[0013] The invention also discloses the use of a novel corrosion and scale inhibitor for closed circulating water to alleviate corrosion and scaling of metal equipment in a closed circulating water system; the usage ratio of the novel corrosion and scale inhibitor for closed circulating water to water in the closed circulating water system is 25-600 mg:1L.

[0014] The invention discloses a method for preparing a novel corrosion and scale inhibitor for closed circulating water, comprising: adding a terpolymer, tungstate and azoles into a solvent and mixing them to obtain the novel corrosion and scale inhibitor for closed circulating water.

[0015] Preferably, the terpolymer is acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer.

[0016] Preferably, the mass fraction of the terpolymer in the novel corrosion and scale inhibitor for closed circulating water is 15-22%.

[0017] Preferably, the tungstate is at least one of sodium tungstate and potassium tungstate.

[0018] Preferably, the mass fraction of tungstate in the novel corrosion and scale inhibitor for closed circulating water is 15-22%.

[0019] Preferably, the azole is at least one of benzotriazole, mercaptobenzothiazole and tolutriazole.

[0020] Preferably, the mass fraction of azoles in the new corrosion and scale inhibitor for closed circulating water is 1.5-2.8%.

[0021] Preferably, the solvent is water.

[0022] Preferably, the mass fraction of the solvent in the novel corrosion and scale inhibitor for closed circulating water is 53.2-68.5%.

[0023] The invention discloses a novel corrosion and scale inhibitor for closed circulating water, comprising a terpolymer, tungstate, azoles and a solvent.

[0024] Preferably, the terpolymer is acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer.

[0025] Preferably, the mass fraction of the terpolymer in the novel corrosion and scale inhibitor for closed circulating water is 10-25%.

[0026] Preferably, the tungstate is at least one of sodium tungstate and potassium tungstate.

[0027] Preferably, the mass fraction of tungstate in the novel corrosion and scale inhibitor for closed circulating water is 10-25%.

[0028] Preferably, the azole is at least one of benzotriazole, mercaptobenzothiazole and tolutriazole.

[0029] Preferably, the mass fraction of azoles in the new corrosion and scale inhibitor for closed circulating water is 1-3%.

[0030] Preferably, the solvent is water.

[0031] Preferably, the mass fraction of the solvent in the novel corrosion and scale inhibitor for closed circulating water is 47-79%.

[0032] The invention discloses a novel corrosion and scale inhibitor for closed circulating water, comprising a terpolymer, tungstate, azoles and a solvent.

[0033] Preferably, the terpolymer is acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer.

[0034] Preferably, the mass fraction of the terpolymer in the novel corrosion and scale inhibitor for closed circulating water is 18-22%.

[0035] Preferably, the tungstate is at least one of sodium tungstate and potassium tungstate.

[0036] Preferably, the mass fraction of tungstate in the novel corrosion and scale inhibitor for closed circulating water is 18-22%.

[0037] Preferably, the azole is at least one of benzotriazole, mercaptobenzothiazole and tolutriazole.

[0038] Preferably, the mass fraction of azoles in the new corrosion and scale inhibitor for closed circulating water is 1.8-2.8%.

[0039] Preferably, the solvent is water.

[0040] Preferably, the mass fraction of the solvent in the novel corrosion and scale inhibitor for closed circulating water is 53.2-62.2%.

[0041] Compared with the prior art, the present invention has the following beneficial effects: The invention provides a novel corrosion and scale inhibitor for closed circulating water. The novel corrosion and scale inhibitor for closed circulating water is obtained by adding a terpolymer, a tungstate and an azole into pure water and mixing them. The terpolymer is an acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer; the tungstate is at least one of sodium tungstate and potassium tungstate; and the azole is at least one of benzotriazole, mercaptobenzothiazole and methylbenzotriazole.

[0042] The new corrosion and scale inhibitor for closed circulating water of the present invention meets environmental protection requirements, does not contain toxic heavy metal components, will not cause heavy metal pollution to the environment during use, meets the requirements of environmental protection laws and regulations, and is beneficial to protecting the ecological environment; the new corrosion and scale inhibitor for closed circulating water of the present invention does not contain phosphorus components, and there is no need to consider the limitation of phosphorus emission indicators during the discharge process, which reduces the monitoring and treatment costs of the discharged water quality and reduces the difficulty of environmental protection compliance; the new corrosion and scale inhibitor for closed circulating water of the present invention is suitable for closed circulating water, can effectively control water quality, prevent corrosion and scale accumulation, protect the stable operation of equipment, extend the life of equipment, improve system efficiency, and can make the corrosion rate of metals, such as carbon steel, lower than 0.005 (mm / a); it is suitable for system maintenance and new system addition, does not require special additional equipment when used, does not need to change the material of buildings or components, does not need special surface treatment of metals, has high economic benefits and strong adaptability.

[0043] The social effect of the present invention: The present invention can be widely used in industrial production. By selecting a suitable water quality ratio and adding an appropriate amount of tungsten, the corrosion rate of the water system can be effectively reduced, the equipment can be protected, the equipment life can be extended, and the equipment maintenance and replacement costs can be reduced. This will help improve the stability and reliability of industrial production, reduce production shutdowns caused by equipment damage, and have a positive social effect on promoting the development of industrial production.

[0044] The economic effect of the present invention is that the present invention can reduce the metal corrosion rate in the circulating water system, thereby reducing the loss and maintenance cost of the equipment. According to statistics, the global loss caused by equipment corrosion is as high as billions of dollars each year. Therefore, the use of the technology of the present invention can save a lot of maintenance and replacement costs for enterprises, improve equipment utilization, reduce production costs, and have significant economic benefits.

[0045] The technical effect of the present invention is as follows: the present invention provides a solution to the corrosion problem under different water quality conditions, and through the support of experimental data, clarifies the influence of adding tungsten elements on the corrosion rate under different conditions. This provides a useful reference and guidance for the field of engineering technology, and provides a new idea and method for solving the water quality corrosion problem in industrial production.

[0046] In summary, the application of the present invention will help reduce the corrosion rate of equipment in industrial production, improve production stability, reduce maintenance costs, save a lot of money for enterprises, and have significant social, economic and technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0048] Figure 1 This is the result of the corrosion rate measurement. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The following first describes the concepts involved in the present application in conjunction with the accompanying drawings. It should be noted that the following description of each concept is only to make the content of the present application easier to understand, and does not limit the scope of protection of the present application; at the same time, the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail with reference to the accompanying drawings and in conjunction with the embodiments.

[0051] Embodiment 1: Preparation of corrosion and scale inhibitor: acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, sodium tungstate and methyl benzotriazole are added into pure water and mixed to obtain corrosion and scale inhibitor. The mass fraction of acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer in the corrosion and scale inhibitor is 20%, the mass fraction of sodium tungstate in the corrosion and scale inhibitor is 20%, the mass fraction of methyl benzotriazole in the corrosion and scale inhibitor is 2.5%, and the mass fraction of pure water in the corrosion and scale inhibitor is 57.5%.

[0052] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test is carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is pure water, the dosage ratio of corrosion and scale inhibitor to experimental water is 50mg:1L, and the dosage ratio of sodium tungstate to experimental water is 10mg:1L.

[0053] Embodiment 2: The preparation of corrosion and scale inhibitor is the same as that in Example 1.

[0054] Determination of corrosion inhibition performance: The corrosion inhibition performance test was carried out by the rotating coupon method, according to GB50050-2007 "Industrial Circulating Cooling Water Treatment Design Specifications". The experimental device is the RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is pure water, the dosage ratio of corrosion and scale inhibitor to experimental water is 100mg:1L, and the dosage ratio of sodium tungstate to experimental water is 20mg:1L.

[0055] Embodiment 3: The preparation of the corrosion and scale inhibitor is the same as in Example 1.

[0056] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test is carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is pure water, the dosage ratio of corrosion and scale inhibitor to experimental water is 150mg:1L, and the dosage of sodium tungstate to experimental water is 30mg:1L.

[0057] Embodiment 4: The preparation of the corrosion and scale inhibitor is the same as in Example 1.

[0058] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test is carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is pure water, the dosage ratio of corrosion and scale inhibitor to experimental water is 200mg:1L, and the dosage ratio of sodium tungstate to experimental water is 40mg:1L.

[0059] Embodiment 5: The preparation of the corrosion and scale inhibitor is the same as in Example 1.

[0060] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test is carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is tap water, the dosage ratio of corrosion and scale inhibitor to experimental water is 200mg:1L, and the dosage ratio of sodium tungstate to experimental water is 40mg:1L.

[0061] Embodiment 6: The preparation of the corrosion and scale inhibitor is the same as in Example 1.

[0062] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test is carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is tap water, the dosage ratio of corrosion and scale inhibitor to experimental water is 250mg:1L, and the dosage ratio of sodium tungstate to experimental water is 50mg:1L.

[0063] Embodiment 7: The preparation of the corrosion and scale inhibitor is the same as in Example 1.

[0064] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test was carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece is made of carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is tap water, the amount of corrosion and scale inhibitor added to the experimental water is 300mg:1L, and the dosage ratio of sodium tungstate to experimental water is 60mg:1L.

[0065] Embodiment 8: The preparation of the corrosion and scale inhibitor is the same as in Example 1.

[0066] Determination of corrosion inhibition performance of corrosion and scale inhibitor: The corrosion inhibition performance test is carried out by rotating coupon method, according to GB50050-2007 "Design Specification for Industrial Circulating Cooling Water Treatment". The experimental device is RCC-II rotating coupon corrosion tester, the test piece material is carbon steel, the test piece speed is 75r / min, the experimental temperature is 45℃, the experimental cycle is 72h, the experimental water is tap water, the dosage ratio of corrosion and scale inhibitor to experimental water is 350mg:1L, and the dosage ratio of sodium tungstate to experimental water is 70mg:1L.

[0067] Experimental Example 1: The corrosion rate was determined by statistically calculating the corrosion rate of carbon steel in a closed circulating water system after the corrosion and scale inhibitor was used according to the method for determining the corrosion inhibition performance of the corrosion and scale inhibitor in Examples 1-8.

[0068] The results are as follows Figure 1 As shown, compared with Examples 2-4, Example 1 shows that under the condition of using pure water as the experimental water distribution, the continuous increase in the usage of the corrosion inhibitor and scale inhibitor within a certain range can continuously reduce the corrosion rate of carbon steel, that is, improve the corrosion inhibition effect; compared with Examples 6-8, Example 5 shows that under the condition of using tap water as the experimental water distribution, the increase in the usage of the corrosion inhibitor and scale inhibitor within a certain range can also reduce the corrosion rate of carbon steel; compared with Example 5, Example 4 shows that the demand for corrosion inhibitor and scale inhibitor using tap water as the experimental water distribution is greater than that using pure water as the experimental water distribution, so the appropriate usage of corrosion inhibitor and scale inhibitor can be selected according to the water quality of the circulating water; and Examples 1-8 show that under the conditions of the corrosion inhibition performance measurement of Examples 1-8, the corrosion rates all meet the corrosion rate requirements of the national standard GB50050-2007, that is, they are all lower than 0.075mm / a, and have excellent corrosion inhibition performance.

[0069] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any form. Any technical personnel in this field may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0070] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the invention to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A method for preparing a new type of corrosion and scale inhibitor for closed circulating water, comprising: The terpolymer, tungstate and azoles are added into a solvent and mixed to obtain a novel corrosion and scale inhibitor for closed-circulation water; The mass fraction of the tungstate in the novel corrosion and scale inhibitor for closed circulating water is 10-25%.

2. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The terpolymer is acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer.

3. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The mass fraction of the terpolymer in the novel corrosion and scale inhibitor for closed circulating water is 10-25%.

4. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The tungstate is at least one of sodium tungstate and potassium tungstate.

5. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The azole is at least one of benzotriazole, mercaptobenzothiazole and methylbenzotriazole.

6. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The mass fraction of the azoles in the novel corrosion and scale inhibitor for closed circulating water is 1-3%.

7. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The solvent is water.

8. The method for preparing a novel corrosion and scale inhibitor for closed circulating water according to claim 1, characterized in that: The mass fraction of the solvent in the new corrosion and scale inhibitor for closed circulating water is 47-79%.

9. A novel corrosion inhibitor and scale inhibitor for closed circulating water, comprising the novel corrosion inhibitor and scale inhibitor for closed circulating water prepared by the method according to any one of claims 1 to 8.

10. The purpose of the new corrosion and scale inhibitor for closed circulating water is to alleviate the corrosion and scaling of metal equipment in the closed circulating water system; the dosage ratio of the new corrosion and scale inhibitor for closed circulating water to water in the closed circulating water system is 25-600mg:1L.

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