Circulating cooling water corrosion and scale inhibitor as well as preparation method, automatic dosing system and application thereof

Abstract

The invention provides a circulating cooling water corrosion and scale inhibitor as well as a preparation method, an automatic dosing system and application thereof. The circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 15%-20% of sodium polyepoxysuccinate, 10%-20% of hydrolytic polymaleic anhydride, 10%-20% of an acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, 10%-15% of a hydroxyl modified polysaccharide derivative, 6%-10% of zinc chloride, 2%-5% of benzotriazole, 0.05%-0.1% of sodium 8-allyloxy-1, 3, 6-pyrene trisulfonate and the balance of water. And the balance of deionized water. The hydroxyl modified polysaccharide derivative is selected from one or two of sodium carboxymethyl cellulose and carboxymethyl chitosan. Based on the circulating cooling water corrosion and scale inhibitor provided by the invention, the problems that the corrosion and scale inhibitor in the prior art easily generates calcium phosphate scale and easily causes pollution are solved.

Description

Technical Field

[0001] The invention relates to the technical field of circulating cooling water treatment, and in particular to a circulating cooling water corrosion and scale inhibitor, a preparation method thereof, an automatic dosing system and application thereof. Background Art

[0002] In the coal chemical production process, the circulating cooling water system is an indispensable industrial auxiliary cooling system, which is responsible for removing the waste heat generated in the industrial production process, ensuring the normal operation of each unit device and reaction process, and plays an important role in ensuring product quality and maintaining production safety. During the operation of the circulating cooling water system, after the cooling water passes through the cooling equipment, cooling tower and pipelines of varying lengths, the water quality will undergo a series of changes such as temperature change, evaporation concentration, and enrichment oxidation, which can easily cause equipment corrosion and scaling, resulting in reduced heat transfer efficiency and serious equipment wear. At present, the most commonly used method to prevent corrosion and scaling is to add corrosion and scale inhibitors with excellent performance. Since conventional corrosion and scale inhibitors are mostly polyphosphates and organic phosphonates, they are prone to produce calcium phosphate scale. If they are directly discharged, they will also cause environmental pollution and high sewage treatment costs. Therefore, it is of great significance to develop a phosphorus-free corrosion and scale inhibitor that can effectively slow down the corrosion and scaling of the circulating cooling water system. Summary of the invention

[0003] The main purpose of the present invention is to provide a circulating cooling water corrosion and scale inhibitor and a preparation method thereof, an automatic dosing system and application thereof, so as to solve the problem that the corrosion and scale inhibitor in the prior art is easy to generate calcium phosphate scale and cause pollution.

[0004] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a circulating cooling water corrosion and scale inhibitor is provided, comprising the following components in weight percentage: 15% to 20% of sodium polyepoxysuccinate, 10% to 20% of hydrolyzed polymaleic anhydride, 10% to 20% of acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 10% to 15% of hydroxyl-modified polysaccharide derivative, 6% to 10% of zinc chloride, 2% to 5% of benzotriazole, 0.05% to 0.1% of sodium 8-allyloxy-1,3,6-pyrenetrisulfonate, and the balance is deionized water; the hydroxyl-modified polysaccharide derivative is selected from one or both of sodium carboxymethyl cellulose and carboxymethyl chitosan.

[0005] Furthermore, in the circulating cooling water corrosion and scale inhibitor, the weight percentages of hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer and zinc chloride are 14% to 18%, 14% to 15% and 8% to 10% respectively.

[0006] According to another aspect of the present invention, a method for preparing a corrosion and scale inhibitor for circulating cooling water is provided, comprising the following steps:

[0007] Step S1, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, and hydroxyl-modified polysaccharide derivative to obtain a first mixed material;

[0008] Step S2, dissolving benzotriazole in deionized water to obtain a second mixture;

[0009] Step S3, after mixing the first mixed material and the second mixed material, adding zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate to dissolve them to obtain a circulating cooling water corrosion and scale inhibitor.

[0010] According to yet another aspect of the present invention, there is provided an automatic dosing system for dosing the corrosion and scale inhibitor for circulating cooling water as described above, comprising:

[0011] A cooling tower for cooling circulating cooling water, the cooling tower being provided with a first water inlet and a first water outlet, the first water inlet being used to connect to a circulating cooling water outlet of a heat exchange device;

[0012] A water collecting tank, wherein the water collecting tank is provided with a second water inlet and a second water outlet, and the second water inlet is connected to the first water outlet;

[0013] A circulating water pump, wherein the circulating water pump is provided with a third water inlet and a third water outlet, and the third water inlet is connected to the second water outlet;

[0014] An automatic dosing device includes a drug storage tank for storing a circulating cooling water corrosion inhibitor and scale inhibitor, an online fluorescence detection device, a metering pump for conveying the circulating cooling water corrosion inhibitor and scale inhibitor to a sump, and a control device; the drug outlet of the drug storage tank is connected to the liquid inlet of the metering pump; the online fluorescence detection device is connected to the control device, and is used to monitor the concentration value of 8-allyloxy-1,3,6-pyrenetrisulfonate sodium in the circulating cooling water flowing out of the third water outlet and send it to the control device; the control devices are respectively connected to the metering pumps, and the control devices receive the concentration value and adjust the flow rate of the metering pump according to the received concentration value.

[0015] Furthermore, the cooling tower includes a tower body and a water tank located below the tower body and connected to the bottom of the tower body; the first water inlet is arranged on the tower body, and the first water outlet is arranged on the water tank; a grid is arranged in the water tank.

[0016] Furthermore, the grid is vertically arranged on the bottom wall of the water storage tank, and divides the water tank at the bottom of the tower into a first tank body and a second tank body in the horizontal direction; the first tank body is located directly below the tower body and is connected to the bottom of the tower body; the second tank body is arranged on the side of the grid away from the tower body (13), and the first water outlet is arranged on the second tank body.

[0017] Furthermore, the automatic dosing system also includes a bypass filter device and a backwash water collection tank. The circulating cooling water inlet is connected to the heat exchange device through a circulating water return main pipeline. The circulating water inlet of the bypass filter device is connected to the circulating water return main pipeline. The filtered water outlet of the bypass filter device is used to supply water to the water storage tank. The backwash wastewater outlet of the bypass filter device is connected to the backwash water collection tank.

[0018] Furthermore, the automatic dosing system also includes a production water replenishment pipeline and a recycled water supply pipeline, which are respectively used to replenish water to the water collection tank.

[0019] According to another aspect of the present invention, there is provided the use of the above circulating cooling water corrosion inhibitor and scale inhibitor in circulating cooling water.

[0020] Furthermore, the pH of the circulating cooling water is 7.0 to 9.5.

[0021] Preferably, 50 to 100 mg of circulating cooling water corrosion and scale inhibitor is added to the circulating cooling water per kilogram of circulating cooling water; the calcium ion concentration of the circulating cooling water is 200 to 1500 mg / L in terms of calcium carbonate, and the total alkalinity of the circulating cooling water is 50 to 350 mg / L.

[0022] By applying the technical scheme of the present invention, sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, and hydroxyl-modified polysaccharide derivatives are used as main components, and zinc chloride and benzotriazole are compounded to obtain a corrosion inhibitor with excellent corrosion inhibition effect and scale inhibition and dispersion performance. The zinc ion has high stability in the corrosion inhibitor and scale inhibitor, making it more suitable for cooling water systems under high alkali, high hardness and high pH conditions, achieving high concentration multiple operation, and reducing equipment corrosion and scaling in the circulating cooling water system. In addition, a certain concentration of fluorescent marker component 8-allyloxy-1,3,6-pyrenetrisulfonic acid sodium is added to the corrosion inhibitor and scale inhibitor. By detecting its concentration, the concentration of the corrosion inhibitor and scale inhibitor in the system can be inferred, which is convenient for online detection and automatic control of drug administration. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0024] Figure 1 A schematic structural diagram of an automatic drug delivery system according to an embodiment of the present invention is shown.

[0025] The above drawings include the following reference numerals:

[0026] 1. Cooling tower; 11. First water inlet; 12. First water outlet; 13. Tower body; 14. Water storage tank; 141. First tank body; 142. Second tank body; 15. Grid;

[0027] 2. water collection tank; 21. second water inlet; 22. second water outlet;

[0028] 3. Circulating water pump; 31. Third water inlet; 32. Third water outlet;

[0029] 4. Drug storage tank;

[0030] 5. Metering pump;

[0031] 6. Bypass filter device;

[0032] 7. Backwash water collection tank;

[0033] 8. Circulating water return main pipeline;

[0034] 91. Production water replenishment pipeline; 92. Recycled water supply pipeline. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0036] As described in the background technology, there is a problem in the prior art that corrosion inhibitors and scale inhibitors are prone to produce calcium phosphate scale and cause pollution. In order to achieve the above purpose, according to one aspect of the present invention, a circulating cooling water corrosion inhibitor and scale inhibitor is provided, comprising the following components in weight percentage: 15% to 20% sodium polyepoxysuccinate, 10% to 20% hydrolyzed polymaleic anhydride, 10% to 20% acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 10% to 15% hydroxyl-modified polysaccharide derivatives, 6% to 10% zinc chloride, 2% to 5% benzotriazole, 0.05% to 0.1% sodium 8-allyloxy-1,3,6-pyrene trisulfonate, and the balance is deionized water; the hydroxyl-modified polysaccharide derivative is selected from one or two of sodium carboxymethyl cellulose and carboxymethyl chitosan.

[0037] The circulating cooling water corrosion and scale inhibitor of the present invention uses sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, and hydroxyl-modified polysaccharide derivatives as main components, and is compounded with zinc chloride and benzotriazole to obtain a corrosion inhibitor with excellent corrosion inhibition effect and scale inhibition and dispersion performance. The zinc ion has high stability in the corrosion and scale inhibitor, making it more suitable for cooling water systems under high alkali, high hardness and high pH conditions, achieving high concentration multiple operation, and reducing equipment corrosion and scaling in the circulating cooling water system. In addition, a certain concentration of fluorescent marker component 8-allyloxy-1,3,6-pyrenetrisulfonic acid sodium is added to the corrosion and scale inhibitor. By detecting its concentration, the concentration of the corrosion and scale inhibitor in the system can be inferred, which is convenient for online detection and automatic control of drug administration.

[0038] The present invention studies the corrosion inhibition and calcium resistance of a single component in the corrosion and scale inhibitor, and compounding is performed according to the characteristics of each component, so that the performance of the agent can achieve better corrosion inhibition, scale inhibition and zinc stabilization effects with the minimum raw material ratio, and saves the agent cost. In addition, each component of the corrosion and scale inhibitor does not contain phosphorus, is easily biodegradable, and will not cause eutrophication of the water body after the circulating water is discharged.

[0039] Among them, sodium polyepoxysuccinate (PESA) has good scale inhibition and dispersion performance for calcium carbonate, calcium sulfate, barium sulfate, calcium fluoride and silicon scale in water, and the scale inhibition effect is better than that of commonly used organic phosphine scale inhibitors. At the same time, sodium polyepoxysuccinate has a certain corrosion inhibition effect. When sodium polyepoxysuccinate is used alone, a lower dosage has a certain corrosion inhibition effect on carbon steel. With the increase of the concentration of sodium polyepoxysuccinate, its corrosion inhibition effect is also enhanced, the corrosion rate of carbon steel gradually decreases, and the corrosion inhibition rate increases. If a better corrosion inhibition effect is to be achieved, the required mass concentration of sodium polyepoxysuccinate is relatively high. When sodium polyepoxysuccinate is used alone as a corrosion inhibitor, its performance is poor compared with other organic phosphoric acid corrosion inhibitors, but because it does not contain phosphorus, it is compounded with other agents to form a phosphorus-free organic corrosion inhibitor. The applicant found that sodium polyepoxysuccinate, benzotriazole, sodium carboxymethyl cellulose and carboxymethyl chitosan have a good synergistic effect, and the corrosion inhibition effect after compounding is significantly enhanced.

[0040] Hydrolyzed polymaleic anhydride (HPMA) has excellent scale inhibition and high temperature resistance, and has a good scale inhibition and dispersion effect on carbonates below 300°C. In addition, hydrolyzed polymaleic anhydride also has a certain corrosion inhibition effect, and the corrosion inhibition effect is better when compounded with zinc salt, which can effectively prevent the corrosion of carbon steel.

[0041] Acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer (AA / AMPS) is a copolymer of acrylic acid (AA) and 2-acrylamide-2-methylpropane sulfonic acid (AMPS). Since the molecular structure contains carboxylic acid groups with good scale inhibition and dispersion performance and sulfonic acid groups with strong polarity, it can improve calcium tolerance, has a significant scale inhibition effect on calcium phosphate, calcium carbonate, zinc scale, etc. in water, can also prevent the deposition of iron oxide, and has excellent dispersibility. It has a significant synergistic effect when compounded with organic phosphine and zinc salt, and is suitable for cooling water systems under high alkalinity, high hardness and high pH conditions. The applicant found that acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer has excellent scale inhibition performance when compounded with sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, sodium carboxymethyl cellulose and carboxymethyl chitosan.

[0042] Zinc salts are the most commonly used cathode corrosion inhibitors. Zinc ions can form a zinc hydroxide precipitation film on the metal surface in the high pH area of ​​the cathode to prevent the redox reaction of the cathode. Zinc salts form films very quickly, so they are often used as pre-filming agents when the system is started. However, the zinc film is soft and not durable. It can be used in combination with components such as sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, benzotriazole, sodium carboxymethyl cellulose and carboxymethyl chitosan to form a stable corrosion inhibition film. In addition, zinc ions tend to precipitate when pH>8.0, thereby losing or reducing the corrosion inhibition ability. By compounding zinc ions with acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer sodium polyepoxysuccinate, sodium carboxymethyl cellulose and carboxymethyl chitosan, zinc ions can have a high stability in corrosion and scale inhibitors without adding organic phosphonates, making them suitable for cooling water systems under high alkali, high hardness and high pH conditions, achieving high concentration multiples operation, and the applicable pH conditions can reach 9.5.

[0043] In order to obtain higher corrosion inhibition and scale inhibition effects, in some embodiments, the weight percentages of hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer and zinc chloride are 14% to 18%, 14% to 15% and 8% to 10%, respectively.

[0044] According to another aspect of the present invention, a method for preparing a corrosion and scale inhibitor for circulating cooling water is provided, comprising the following steps:

[0045] Step S1, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and hydroxyl-modified polysaccharide derivative to obtain a first mixed material;

[0046] Step S2, dissolving benzotriazole in deionized water to obtain a second mixture;

[0047] Step S3, after mixing the first mixed material and the second mixed material, adding zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate to dissolve them to obtain a circulating cooling water corrosion and scale inhibitor.

[0048] Sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, and hydroxyl-modified polysaccharide derivatives are mixed to form a uniform system, benzotriazole is dissolved in deionized water, and the two are mixed and then zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added, which is conducive to forming a uniform and stable circulating cooling water corrosion and scale inhibitor.

[0049] In one embodiment, step S1, step S2 and step S3 are performed at a temperature of 15° C.-35° C., which is simple to operate and low in cost.

[0050] According to another aspect of the present invention, there is provided an automatic dosing system for dosing the corrosion and scale inhibitor in the circulating cooling water as above, Figure 1 As shown, including:

[0051] A cooling tower 1 for cooling circulating cooling water, the cooling tower 1 being provided with a first water inlet 11 and a first water outlet 12, the first water inlet 11 being used to connect to a circulating cooling water outlet of a heat exchange device;

[0052] The water collecting pool 2 is provided with a second water inlet 21 and a second water outlet 22, and the second water inlet 21 is connected to the first water outlet 12;

[0053] A circulating water pump 3, wherein the circulating water pump 3 is provided with a third water inlet 31 and a third water outlet 32, and the third water inlet 31 is connected to the second water outlet 22;

[0054] An automatic dosing device, the automatic dosing device includes a drug storage tank 4 for storing a circulating cooling water corrosion inhibitor and scale inhibitor, an online fluorescence detection device, a metering pump 5 for conveying the circulating cooling water corrosion inhibitor and scale inhibitor to the water collection tank 2, and a control device; the drug outlet of the drug storage tank 4 is connected to the liquid inlet of the metering pump 5; the online fluorescence detection device is connected to the control device, and is used to monitor the concentration value of 8-allyloxy-1,3,6-pyrenetrisulfonate sodium in the circulating cooling water flowing out of the third water outlet 32 ​​and send it to the control device; the control device is respectively connected to the metering pump 5, and the control device receives the concentration value and adjusts the flow rate of the metering pump 5 according to the received concentration value.

[0055] The current daily management of circulating cooling water systems mainly relies on water quality analysis results to adjust the dosage. The adjustment lag exacerbates corrosion and scaling, and easily causes waste of medicines. Based on the automatic drug delivery system of the present invention, the concentration of the fluorescent substance 8-allyloxy-1,3,6-pyrene trisulfonate sodium in the circulating cooling water is detected by an online fluorescence detection device. When the content of the fluorescent substance in the water quality is lower than the set value (it is inferred that the content of the corrosion and scale inhibitor in the water is lower than the set value), the control device controls the flow of the metering pump 5 to increase accordingly; when the content of the medicine in the water quality is higher than the set value, the control device controls the flow of the metering pump 5 to decrease accordingly, thereby realizing online detection and precise automatic drug delivery of the corrosion and scale inhibitor in the circulating cooling water.

[0056] The cooling tower 1 may adopt natural ventilation or mechanical ventilation. In some embodiments, the cooling tower 1 adopts a counter-flow mechanical ventilation cooling tower.

[0057] In some embodiments, the cooling tower 1 includes a tower body 13 and a water tank 14 located below the tower body 13 and connected to the bottom of the tower body 13; the first water inlet 11 is arranged on the tower body, and the first water outlet 12 is arranged on the water tank 14; a grid 15 is arranged in the water tank 14. The grid 15 can be used to intercept impurities in the water to prevent clogging of the heat exchange equipment.

[0058] Furthermore, the grid 15 is vertically arranged on the inner bottom wall of the water storage tank 14, and divides the water tank at the bottom of the tower into a first tank body 141 and a second tank body 142 in the horizontal direction; the first tank body 141 is located directly below the tower body 13 and is connected to the bottom of the tower body 13; the second tank body 142 is arranged on the side of the grid away from the tower body 13, and the first water outlet 12 is arranged on the second tank body 142. Thus, the cooled water first enters the first tank body 141, then passes through the grid 15 into the second water tank, and then flows out from the first water outlet 12 arranged on the second tank body 142 into the water collection tank 2, so as to better intercept impurities in the water.

[0059] In one embodiment, the water storage tank 14 and the water collection tank 2 are both semi-underground, which is beneficial for saving space and reducing water evaporation.

[0060] In some embodiments, the automatic drug delivery system further includes a bypass filter device 6 and a backwash water collection tank 7, the circulating cooling water inlet is connected to the heat exchange device through a circulating water return main pipeline 8, the circulating water inlet of the bypass filter device 6 is connected to the circulating water return main pipeline 8, the filtered water outlet of the bypass filter device 6 is used to supply water to the water storage tank 14, and the backwash wastewater outlet of the bypass filter device 6 is connected to the backwash water collection tank 7. The bypass filter system can periodically treat a portion of the water in the circulating cooling water system, remove suspended matter and microorganisms in the water, improve water quality, reduce corrosion and scaling of the heat exchange device and pipelines, and thus improve the operating efficiency of the entire system and the service life of the equipment. In the prior art, the bypass filter system generally includes a bypass filter, a bypass filter pump, a backwash device, and a control device. In one embodiment, the bypass filter is a gravity valveless filter, and the filtered water can be directly used to supply water to the water storage tank 14. The backwash water collection tank 7 collects the backwash wastewater of the bypass filter, which can be reused after being treated by a wastewater treatment process.

[0061] In one embodiment, the online fluorescence detection device is a fluorescence sensor, the third water outlet 32 ​​is connected to the heat exchange device through a delivery pipeline, and the fluorescence sensor is arranged on the delivery pipeline. The fluorescence sensor can monitor the concentration of the fluorescent substance in the water in real time, can be installed in a pipeline or a container, and is connected to the control device to realize automatic adjustment of the amount of corrosion and scale inhibitor added to the cooling water.

[0062] In some embodiments, the automatic dosing system further includes a production water replenishment pipeline 91 and a regenerated water supply pipeline 92, which are respectively used to replenish water to the water collection tank 2. The production water replenishment pipeline 91 and the regenerated water supply pipeline 92 can replenish fresh water to the water collection tank 2 to compensate for the water loss caused by evaporation, leakage and sewage discharge in the circulating cooling water system.

[0063] According to another aspect of the present invention, there is provided the use of the above circulating cooling water corrosion inhibitor and scale inhibitor in circulating cooling water.

[0064] The circulating cooling water corrosion and scale inhibitor of the present invention has excellent corrosion inhibition effect and scale inhibition and dispersion performance, and the zinc ion has high stability in the corrosion and scale inhibitor, making it more suitable for cooling water systems under high alkali, high hardness and high pH conditions. In some embodiments, the pH of the circulating cooling water is 7.0 to 9.5.

[0065] In one embodiment, 50-100 mg of circulating cooling water corrosion and scale inhibitor is added to the circulating cooling water per kilogram of circulating cooling water; the calcium ion concentration of the circulating cooling water is 200-1500 mg / L in terms of calcium carbonate, and the total alkalinity of the circulating cooling water is 50-350 mg / L. With the above-mentioned lower concentration of the agent, a better corrosion inhibition, scale inhibition and zinc stabilization effect can be achieved, saving the agent cost.

[0066] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0067] Example 1

[0068] A circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 18% sodium polyepoxysuccinate, 18% hydrolyzed polymaleic anhydride, 12% sodium carboxymethyl cellulose, 14% acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 9% zinc chloride, 3% benzotriazole, 0.05% sodium 8-allyloxy-1,3,6-pyrene trisulfonate, and the balance is deionized water.

[0069] The preparation method of the circulating cooling water corrosion and scale inhibitor comprises the following steps:

[0070] Step 1: at room temperature, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and sodium carboxymethyl cellulose to obtain a first mixture;

[0071] Step 2: dissolving benzotriazole in deionized water at room temperature to obtain a second mixture.

[0072] Step three, at room temperature, after mixing the first mixed material and the second mixed material, zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added and dissolved to obtain a circulating cooling water corrosion and scale inhibitor.

[0073] Example 2

[0074] A circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 20% sodium polyepoxysuccinate, 18% hydrolyzed polymaleic anhydride, 10% carboxymethyl chitosan, 15% acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 8% zinc chloride, 2% benzotriazole, 0.05% sodium 8-allyloxy-1,3,6-pyrene trisulfonate, and the balance is deionized water.

[0075] The preparation method of the circulating cooling water corrosion and scale inhibitor comprises the following steps:

[0076] Step 1: at room temperature, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and carboxymethyl chitosan to obtain a first mixture;

[0077] Step 2: dissolving benzotriazole in deionized water at room temperature to obtain a second mixture.

[0078] Step three, at room temperature, after mixing the first mixed material and the second mixed material, zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added and dissolved to obtain a circulating cooling water corrosion and scale inhibitor.

[0079] Example 3

[0080] A circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 15% sodium polyepoxysuccinate, 14% hydrolyzed polymaleic anhydride, 15% sodium carboxymethyl cellulose, 14% acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 10% zinc chloride, 5% benzotriazole, 0.1% sodium 8-allyloxy-1,3,6-pyrene trisulfonate, and the balance is deionized water.

[0081] The preparation method of the circulating cooling water corrosion and scale inhibitor comprises the following steps:

[0082] Step 1: at room temperature, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and sodium carboxymethyl cellulose to obtain a first mixture;

[0083] Step 2: dissolving benzotriazole in deionized water at room temperature to obtain a second mixture.

[0084] Step three, at room temperature, after mixing the first mixed material and the second mixed material, zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added and dissolved to obtain a circulating cooling water corrosion and scale inhibitor.

[0085] Example 4

[0086] A circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 15% sodium polyepoxysuccinate, 15% hydrolyzed polymaleic anhydride, 10% carboxymethyl chitosan, 15% acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 6% zinc chloride, 2% benzotriazole, 0.05% sodium 8-allyloxy-1,3,6-pyrene trisulfonate, and the balance is deionized water.

[0087] The preparation method of the circulating cooling water corrosion and scale inhibitor comprises the following steps:

[0088] Step 1: at room temperature, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and carboxymethyl chitosan to obtain a first mixture;

[0089] Step 2: dissolving benzotriazole in deionized water at room temperature to obtain a second mixture.

[0090] Step three, at room temperature, after mixing the first mixed material and the second mixed material, zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added and dissolved to obtain a circulating cooling water corrosion and scale inhibitor.

[0091] Example 5

[0092] A circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 20% sodium polyepoxysuccinate, 15% hydrolyzed polymaleic anhydride, 10% sodium carboxymethyl cellulose, 10% acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, 10% zinc chloride, 5% benzotriazole, 0.1% sodium 8-allyloxy-1,3,6-pyrene trisulfonate, and the balance is deionized water.

[0093] The preparation method of the circulating cooling water corrosion and scale inhibitor comprises the following steps:

[0094] Step 1: at room temperature, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and sodium carboxymethyl cellulose to obtain a first mixture;

[0095] Step 2: dissolving benzotriazole in deionized water at room temperature to obtain a second mixture.

[0096] Step three, at room temperature, after mixing the first mixed material and the second mixed material, zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added and dissolved to obtain a circulating cooling water corrosion and scale inhibitor.

[0097] Comparative Example 1

[0098] The only difference between it and Example 1 is that sodium carboxymethyl cellulose is not added.

[0099] Comparative Example 2

[0100] The only difference between it and Example 1 is that sodium carboxymethyl cellulose is not added, and the weight percentage of sodium polyepoxysuccinate in the circulating cooling water corrosion and scale inhibitor is 30%, as follows:

[0101] A circulating cooling water corrosion and scale inhibitor comprises the following components in percentage by weight: 30% sodium polyepoxysuccinate, 18% hydrolyzed polymaleic anhydride, 14% acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, 9% zinc chloride, 3% benzotriazole, 0.05% sodium 8-allyloxy-1,3,6-pyrenetrisulfonate, and the balance is deionized water.

[0102] The preparation method of the circulating cooling water corrosion and scale inhibitor comprises the following steps:

[0103] Step 1: at room temperature, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride and sodium acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer to obtain a first mixture;

[0104] Step 2: dissolving benzotriazole in deionized water at room temperature to obtain a second mixture.

[0105] Step three, at room temperature, after mixing the first mixed material and the second mixed material, zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate are added and dissolved to obtain a circulating cooling water corrosion and scale inhibitor.

[0106] The circulating cooling water corrosion and scale inhibitor prepared in this comparative example showed precipitation after being left for one week.

[0107] Comparative Example 3

[0108] The only difference between the embodiment 1 and the embodiment 1 is that the weight percentage of sodium carboxymethyl cellulose is 5%.

[0109] Comparative Example 4

[0110] The only difference between the embodiment 1 and the embodiment 1 is that the weight percentage of sodium polyepoxysuccinate is 30%.

[0111] The circulating cooling water corrosion and scale inhibitor prepared in this comparative example showed precipitation after being left for one week.

[0112] Performance Testing

[0113] The calcium carbonate inhibition performance, zinc stabilization performance, silicon scale inhibition performance, and corrosion inhibition performance of the circulating cooling water corrosion and scale inhibitor (hereinafter referred to as the agent) prepared in the examples and comparative examples were tested, and the test method is as follows:

[0114] (1) The test method for calcium carbonate inhibition performance is as follows:

[0115] Add analytically pure calcium chloride and sodium bicarbonate to distilled water to prepare a prepared water sample, in which the concentration of calcium ions and bicarbonate is 250 mg / L. Take 750 ml of the prepared water sample and place it in each 1000 ml beaker. One of the beakers does not contain water treatment agent, and the rest are added with a certain amount of agent. Place the beaker in a constant temperature water bath that has been heated to about 50°C, and then heat it to 80°C for evaporation and concentration. Start constant temperature and record the time. When the test evaporation concentration reaches the 500mL scale line, take out the beaker. Transfer the test solution to a 500mL volumetric flask, shake it well, cover it and continue to place it in a constant temperature water bath at 80°C. Keep the temperature constant for 10 hours from the start of the timing. Cool to room temperature, filter with medium-speed quantitative filter paper, and determine the calcium hardness, and calculate the scale inhibition rate of the agent according to the following formula:

[0116]

[0117] Where: Ca0 2+ Indicates the Ca measured before the test solution test 2+ The theoretical Ca is obtained by multiplying the concentration by the concentration factor. 2+ concentration;

[0118] Ca0 2+ Indicates the test solution with antiscalant added, Ca after the test 2+concentration;

[0119] Ca2 2+ It indicates the Ca content of the test solution without antiscalant (blank) under the same test conditions. 2+ concentration.

[0120] Note: Ca in this article 2+ and HCO3 - All are calculated as CaCO3.

[0121] The test results of the calcium carbonate resistance performance of the embodiments and comparative examples are shown in Table 1.

[0122] Table 1

[0123] Drug concentration (mg / L) Scale inhibition rate (%) Example 1 60 99.86 Example 2 60 97.93 Example 3 60 98.12 Example 4 60 94.25 Example 5 60 95.33 Comparative Example 1 60 79.12 Comparative Example 2 - - Comparative Example 3 60 85.14 Comparative Example 4 - -

[0124] Note: “-” indicates that the relevant test was not conducted.

[0125] (2) The test method for zinc stabilization performance is as follows:

[0126] Add reagent grade ZnCl2 to distilled water to prepare a mixture containing 50 mg / L ZnCl2 (Zn 2+ The solution was prepared with a pH of 1. The solution contained 278 mg / L Ca 2+ (calculated as CaCO3), 167mg / L Mg 2+ (calculated as CaCO3), 333mg / L total alkalinity (calculated as CaCO3) standard solution. Prepare 5g / L pharmaceutical stock solution. Add a certain volume of pharmaceutical stock solution to a 500mL volumetric flask as required, add 50mL ZnCl2 solution, and add standard solution to make up the volume. Use 0.5% NaOH solution (by weight percentage) to adjust the pH value to 8.0, place the volumetric flask in a 40℃ water bath, keep the temperature constant for 24 hours, take it out, cool it to room temperature, filter it with medium-speed quantitative filter paper, and determine Zn 2+ . And calculate the zinc stabilization rate R of the agent according to the following formula:

[0127]

[0128] Where: Zn0 2+ Indicates the Zn actually measured before the test solution test 2+ concentration;

[0129] Zn1 2+ Indicates the Zn after the test with the antiscalant solution 2+ concentration;

[0130] Zn2 2+ It indicates the Zn content of the test solution without antiscalant (blank) under the same test conditions. 2+ concentration.

[0131] The zinc stabilization performance test results of the embodiments and comparative examples are shown in Table 2.

[0132] Table 2

[0133] Drug concentration (mg / L) Zinc stabilization rate (%) Example 1 60 64.33 Example 2 60 62.80 Example 3 60 63.19 Example 4 60 50.24 Example 5 60 55.48 Comparative Example 1 60 23.46 Comparative Example 2 - - Comparative Example 3 60 41.53 Comparative Example 4 - -

[0134] Note: “-” indicates that the relevant test was not conducted.

[0135] (3) Corrosion inhibition performance The test was conducted for 168 hours according to GB / T 18175-2014 “Determination of corrosion inhibition performance of water treatment agents - Rotating plate method”, with a dosing concentration of 60 mg / L. The corrosion rates of the agents in the examples and comparative examples on carbon steel are shown in Table 3.

[0136] Table 3

[0137] Drug concentration (mg / L) Corrosion rate (mm / a) Example 1 60 0.014 Example 2 60 0.026 Example 3 60 0.021 Example 4 60 0.035 Example 5 60 0.031 Comparative Example 1 60 0.071 Comparative Example 2 - - Comparative Example 3 60 0.068 Comparative Example 4 - -

[0138] Note: “-” indicates that the relevant test was not conducted.

[0139] It can be seen from Table 1, Table 2 and Table 3 that the circulating cooling water corrosion inhibitor and scale inhibitor based on Examples 1-5 of the present invention has excellent corrosion inhibition effect and scale inhibition and dispersion performance, and zinc ions have high stability in the corrosion inhibitor and scale inhibitor, which can effectively slow down system corrosion and scaling, increase the operating concentration multiple, reduce system water consumption, and extend the life and production cycle of heat exchange equipment. It is suitable for circulating cooling water systems under high alkali, high hardness and high pH conditions.

[0140] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A circulating cooling water corrosion and scale inhibitor, characterized in that: The invention comprises the following components in weight percentage: 15% to 20% sodium polyepoxysuccinate, 10% to 20% hydrolyzed polymaleic anhydride, 10% to 20% acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer, 10% to 15% hydroxyl-modified polysaccharide derivative, 6% to 10% zinc chloride, 2% to 5% benzotriazole, 0.05% to 0.1% sodium 8-allyloxy-1,3,6-pyrenetrisulfonate, and the balance is deionized water; the hydroxyl-modified polysaccharide derivative is selected from one or both of sodium carboxymethyl cellulose and carboxymethyl chitosan.

2. The circulating cooling water corrosion and scale inhibitor according to claim 1, characterized in that: The weight percentages of the hydrolyzed polymaleic anhydride, the acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and the zinc chloride are 14% to 18%, 14% to 15% and 8% to 10% respectively.

3. The method for preparing a circulating cooling water corrosion and scale inhibitor according to claim 1 or 2, characterized in that: The steps include: Step S1, mixing sodium polyepoxysuccinate, hydrolyzed polymaleic anhydride, acrylic acid-2-acrylamide-2-methylpropanesulfonic acid copolymer and hydroxyl-modified polysaccharide derivative to obtain a first mixed material; Step S2, dissolving benzotriazole in deionized water to obtain a second mixture; Step S3, after mixing the first mixed material and the second mixed material, adding zinc chloride and sodium 8-allyloxy-1,3,6-pyrenetrisulfonate to dissolve them to obtain a circulating cooling water corrosion and scale inhibitor.

4. An automatic dosing system for dosing the corrosion and scale inhibitor for circulating cooling water according to claim 1 or 2, characterized in that: include: A cooling tower (1) for cooling circulating cooling water, the cooling tower (1) being provided with a first water inlet (11) and a first water outlet (12), the first water inlet (11) being used to connect to a circulating cooling water outlet of a heat exchange device; A water collecting pool (2), wherein the water collecting pool (2) is provided with a second water inlet (21) and a second water outlet (22), and the second water inlet (21) is connected to the first water outlet (12); A circulating water pump (3), wherein the circulating water pump (3) is provided with a third water inlet (31) and a third water outlet (32), and the third water inlet (31) is connected to the second water outlet (22); An automatic dosing device, the automatic dosing device comprising a drug storage tank (4) for storing a circulating cooling water corrosion inhibitor, an online fluorescence detection device, a metering pump (5) for conveying the circulating cooling water corrosion inhibitor to the water collection tank (2), and a control device; the drug outlet of the drug storage tank (4) is connected to the liquid inlet of the metering pump (5); the online fluorescence detection device is connected to the control device and is used to monitor the concentration value of 8-allyloxy-1,3,6-pyrenetrisulfonate sodium in the circulating cooling water flowing out of the third water outlet (32) and send it to the control device; the control device is respectively connected to the metering pump (5), and the control device receives the concentration value and adjusts the flow rate of the metering pump (5) according to the received concentration value.

5. The automatic drug delivery system according to claim 4, characterized in that: The cooling tower (1) comprises a tower body (13) and a water storage tank (14) located below the tower body (13) and connected to the bottom of the tower body (13); the first water inlet (11) is arranged on the tower body; the first water outlet (12) is arranged on the water storage tank (14); and a grid (15) is arranged in the water storage tank (14).

6. The automatic drug delivery system according to claim 5, characterized in that: The grid (15) is vertically arranged on the inner bottom wall of the water storage tank (14), and divides the water tank at the bottom of the tower into a first tank body (141) and a second tank body (142) in the horizontal direction; the first tank body (141) is located directly below the tower body (13) and is connected to the bottom of the tower body (13); the second tank body (142) is arranged on a side of the grid away from the tower body (13); and the first water outlet (12) is arranged on the second tank body (142).

7. The automatic drug delivery system according to claim 5, characterized in that: The automatic drug delivery system further comprises a bypass filter device (6) and a backwash water collection tank (7); the circulating cooling water inlet is connected to the heat exchange device via a circulating water return main pipeline (8); the circulating water inlet of the bypass filter device (6) is connected to the circulating water return main pipeline (8); the filtered water outlet of the bypass filter device (6) is used to supply water to the water storage tank (14); and the backwash wastewater outlet of the bypass filter device (6) is connected to the backwash water collection tank (7).

8. The automatic drug delivery system according to claim 5, characterized in that: The automatic drug delivery system further comprises a production water replenishment pipeline (91) and a regenerated water supply pipeline (92), which are respectively used to replenish water to the water collection tank (2).

9. Use of the circulating cooling water corrosion inhibitor and scale inhibitor according to claim 1 or 2 in circulating cooling water.

10. The use of the circulating cooling water corrosion and scale inhibitor according to claim 9 in circulating cooling water, characterized in that: The pH of circulating cooling water is 7.0-9.5; Preferably, the circulating cooling water corrosion and scale inhibitor is added to the circulating cooling water in an amount of 50 to 100 mg per kilogram of circulating cooling water; Calculated in terms of calcium carbonate, the calcium ion concentration of the circulating cooling water is 200 to 1500 mg / L, and the total alkalinity of the circulating cooling water is 50 to 350 mg / L.

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