A self-scaling and self-sterilizing circulating cooling water system and a method for self-scaling and self-sterilizing circulating cooling water system

Abstract

The present invention provides a self-scaling and self-sterilizing circulating cooling water system, comprising an electrochemical electrolysis device arranged on a pipeline of the circulating water system; the electrochemical electrolysis device is used to convert chloride ion-containing water into H + and oxidizing chlorine species, and then the H-rich + The system of the present invention directly connects the electrochemical electrolysis device to the original circulating cooling water system, and utilizes the action of the electrochemical electrolysis device to generate H-rich + and oxidizing chlorine species in water and input the water into the pipeline for scale inhibition and sterilization of the water, replacing the traditional technical means of adding sulfuric acid, scale inhibitors and bactericides into the circulating water system.

Description

Technical Field

[0001] The invention relates to the technical field of industrial circulating cooling water treatment, and in particular to a self-scaling and self-sterilizing circulating cooling water system and a self-scaling and self-sterilizing method for the circulating cooling water system. Background Art

[0002] The circulating cooling water system is a system with a large water consumption in the industrial system. Its stable operation is of great significance to the safe and stable production of the enterprise. At present, the circulating cooling water system is facing problems such as scaling and bacterial growth. The hardness ions in the circulating water, such as calcium ions and HCO3 - The scaling deposition and sludge formed by microorganisms and their secretions in the circulating water will clog the pipes and accelerate the corrosion of the pipes, seriously affecting the safe operation of the circulating water system.

[0003] Common anti-scaling methods in the circulating water treatment process include lime softening and sulfuric acid acidification, and common sterilization methods include adding liquid chlorine, sodium hypochlorite and other sterilants. However, due to the dangers of such drugs, their storage and transportation greatly increase the cost. In addition, the addition of these chemicals increases the salt content of the system, which is easy to cause system corrosion. Electrochemical oxidation technology has attracted widespread attention in the field of circulating water treatment due to its green and wide applicability. In the traditional single-chamber electrolysis system, the anode surface can produce H + and oxidizing chlorine species (HClO, Cl2, ClO - ). During the electrolysis reaction at the anode, OH is produced during the electrolysis of water at the cathode. - , which will neutralize the H produced by anodic oxidation + , resulting in the pH of the electrolyzed water being neutral, and the need to add acid to the circulating water cannot be met. In addition, due to the limitation of the anode oxidation area, the content of oxidizing chlorine species produced by anode electrolysis is not high, and these species will diffuse to the cathode surface and be reduced to chloride ions, resulting in a low content of oxidizing chlorine species in the final effluent, which cannot replace the traditional method of adding fungicides to the circulating water system.

[0004] Although the existing reaction system using ion exchange membrane to separate the cathode and anode can avoid acid-base separation and reduction of active chlorine species at the cathode, the ion exchange membrane reaction system is extremely demanding on the quality of the influent water. When used to treat circulating water, the ion exchange membrane will be quickly contaminated and lose ion permeability and conductivity due to the presence of metal ions, silicon, hardness, turbidity, etc. in the circulating water. Therefore, this reaction system cannot be used to add H2O2 to the circulating water system in situ. + and oxidizing chlorine species. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a self-scaling and self-sterilizing circulating cooling water system, comprising an electrochemical electrolysis device arranged on the pipeline of the circulating water system; the electrochemical electrolysis device is used to convert water containing chloride ions into H at the anode. + and oxidizing chlorine species, and then the H-rich + and oxidizing chlorine species are transported into the pipeline.

[0006] On the basis of the above scheme, the water used for electrolysis in the electrochemical electrolysis device comes from the circulating water in the pipeline.

[0007] On the basis of the above scheme, the electrochemical electrolysis device comprises an electrolysis unit and a power supply for powering the electrolysis unit; the electrolysis unit comprises an anode and a cathode; the anode is a filter element electrode, the interior of which is a cavity, and the wall is a porous structure, which is rich in H + The water body with oxidizing chlorine species is drawn from the internal cavity of the anode.

[0008] On the basis of the above solution, the cathode is a porous mesh tube electrode, and the anode is sleeved inside the cathode.

[0009] On the basis of the above scheme, the electrolysis unit further comprises an electrolytic cell, wherein the cathode is arranged in the electrolytic cell; a water inlet is arranged at the bottom of the electrolytic cell, an overflow port is arranged at the top, and a water inlet is arranged at the top of the anode for extracting H-rich water from the anode. + and oxidizing chlorine species in water bodies.

[0010] The present invention also provides a method for self-scaling and self-sterilization of a circulating cooling water system, in which an electrochemical electrolysis device is arranged on the pipeline of the circulating water system and the electrochemical electrolysis device is used to convert chloride ion-containing water into H at the anode. + and oxidizing chlorine species, and then the H-rich + The water containing oxidizing chlorine species is transported to the pipeline, and the electrochemical electrolysis device uses the electrochemical electrolysis device in the above-mentioned system.

[0011] The self-scaling and self-sterilizing circulating cooling water system of the present invention is directly connected to the electrochemical electrolysis device in the original circulating cooling water system, and the electrochemical electrolysis device is used to generate H-rich + The water body containing chlorine and oxidizing species is input into the pipeline for scale prevention and sterilization of the water body, replacing the traditional technical means of adding sulfuric acid, scale inhibitors and bactericides into the circulating water system. Since chloride ions are common and exist in large quantities in the circulating water, the present invention can generate HClO, Cl2, ClO at the anode without adding additional chloride ions. -It avoids secondary pollution to water bodies and the introduction of foreign ions, so it has broad market prospects and environmental significance. The electrochemical electrolysis device in the system of the present invention uses the filter element electrode as the anode. Due to the H generated by anode electrolysis, + The oxidizing chlorine species are concentrated in the liquid film on the anode surface, so the H-rich + The process of extracting oxidizing chlorine species from water is simple and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the circulating cooling water system of the present invention;

[0013] Figure 2 It is a schematic diagram of the structure of the electrolysis unit in the circulating cooling water system of the present invention;

[0014] Figure 3 is the pH value of the water outlet at different current densities in the use examples of the present invention;

[0015] Figure 4 It is the content of residual chlorine in the outlet water of the water pump at different current densities in the use examples of the present invention. DETAILED DESCRIPTION

[0016] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0017] Example 1

[0018] like Figure 1 As shown, the present invention provides a self-scaling and self-sterilizing circulating cooling water system, comprising an electrochemical electrolysis device 2 arranged on a pipeline 1 of the circulating water system; the electrochemical electrolysis device 2 is used to convert water containing chloride ions into H at the anode. + and oxidizing chlorine species, and then the H-rich + The water containing oxidizing chlorine species is transported to pipeline 1. Among them, the oxidizing chlorine species refers to HClO, Cl2, ClO converted into by chloride ions at the anode. - During the operation of the electrochemical electrolysis device 2, H + The oxidizing chlorine species will be enriched in the liquid film on the anode surface, + After the water containing oxidizing chlorine species is separated from the anode surface, the anode will continue to generate new H-rich water. + and oxidizing chlorine species in the water, so the process is continuous.

[0019] Rich in H +The water containing oxidizing chlorine species is input into the pipeline 1 of the circulating cooling water system, which plays the role of in-situ acidification and bactericide, and can effectively inhibit the scaling tendency of the circulating water system and the formation of microbial sludge.

[0020] Figure 1 In the electrochemical electrolysis device 2, the water used for electrolysis comes from the circulating water in the pipeline 1. Since chloride ions are common and exist in large quantities in the circulating water, the present invention can generate HClO, Cl2, ClO at the anode without adding additional chloride ions. - In addition to using circulating water, water with chloride ions added can also be used, which will not be described in detail here.

[0021] As a specific implementation scheme, Figure 1 and 2 As shown, the electrochemical electrolysis device 2 includes an electrolysis unit 2-1 and a power supply for supplying power to the electrolysis unit 2-1; the electrolysis unit 2-1 includes an anode 2-11 and a cathode 2-12; + The water body with oxidizing chlorine species comes from the vicinity of the anode 2-11.

[0022] As an implementable solution, the anode 2-11 is a filter element electrode, which has a cavity inside and a porous structure on the wall, a filtration accuracy of 0.45-50 μm, a porosity of 35-45%, and is rich in H + The water containing oxidizing chlorine species is extracted from the internal cavity of the anode 2-11. The cathode 2-12 is a porous mesh tube electrode, and the anode 2-11 is sleeved in the cathode 2-12. The distance between the anode 2-11 and the cathode 2-12 is 1-10 cm. The electrolysis unit 2-1 also includes an electrolytic cell 2-13, and the cathode 2-12 is arranged in the electrolytic cell 2-13; the bottom of the electrolytic cell 2-13 is provided with a water inlet 2-14, the upper part is provided with an overflow port 2-15, and the top of the anode 2-11 is provided with a water inlet 2-14 for extracting H-rich water in the anode 2-11. + The water inlet 2-14 is arranged between the anode 2-11 and the cathode 2-12. The water inlet 2-16 extracts the oxidizing chlorine-rich species and H generated by electrolysis on the surface of the anode 2-11. + of acidic liquid.

[0023] The material of the anode 2-11 is a titanium filter element, a titanium suboxide filter element or a carbon filter element. As a preferred solution, when the anode 2-11 is a titanium filter element, a metal oxide coating is sintered on the surface, and the metal oxide is SnO2, Sb2O5, RuO2, IrO2 or a multi-element doped metal oxide. Compared with the untreated titanium filter element electrode, the treated electrode has a low working voltage during use, low energy consumption, strong corrosion resistance and long service life.

[0024] The cathode 2 - 12 is made of stainless steel or titanium.

[0025] The working principle of the system in this embodiment is: the circulating water in the pipeline 1 of the circulating water system is pumped out by a pump and then input into the electrolytic cell 2-13 from the water inlet 2-14. During the electrolysis process, H is generated near the anode 2-11. + and oxidizing chlorine species (HClO, Cl2, ClO - etc.), and use a pump to continuously extract H-rich water from the pumping port 2-16. + and oxidizing chlorine species and return the water to pipeline 1, playing the role of in-situ acidification and bactericide, which can effectively inhibit the scaling tendency of the circulating water system and the formation of microbial sludge; + The water body of the oxidizing chlorine species is continuously extracted and generated. In addition to being extracted by the filling and pumping port 2-16, the excess water entering the electrolytic cell 2-13 will flow out from the overflow port 2-15 near the cathode 2-12 and be discharged.

[0026] Example 2

[0027] Based on the circulating cooling water system in Example 1, this embodiment provides a method for self-scaling and self-sterilization of a circulating cooling water system. Specifically, an electrochemical electrolysis device is arranged on the pipeline 1 of the circulating water system and the electrochemical electrolysis device is used to convert the chloride ion-containing water into H at the anode. + and oxidizing chlorine species, and then the H-rich + The water containing oxidizing chlorine species is transported to pipeline 1. The electrochemical electrolysis device uses the electrochemical electrolysis device 2 in the system of Example 1. The content of the electrochemical electrolysis device 2 is not repeated here.

[0028] Example 1

[0029] Prepare HCO3- concentration of 10mmol / L and Ca 2+ The concentration is 5mmol / L, Cl - Simulated circulating water with a concentration of 10mmol / L.

[0030] Electrolytic unit: The effective volume of the electrolytic cell 2-13 is 1L; the anode 2-11 uses a titanium filter element electrode with a porosity of 34-45% and a filtration accuracy of 1μm, a diameter of 20mm and a length of 100mm; the cathode 2-12 uses a stainless steel mesh tube electrode; the distance between the anode 2-11 and the cathode 2-12 is 2cm; the water inlet rate of the water inlet 2-14 is 400ml / min, and the extraction rate of the water extraction port 2-16 is 100mL / min.

[0031] At a current density of 5 mA / cm 2 , 10mA / cm 2 , 20mA / cm 2 、30mA / cm 2 The following test is conducted to test the treatment effect of the system of Example 1 on circulating water. The treatment time is 30 minutes, and the pH value and residual chlorine (referring to oxidizing chlorine species) of the water discharged from the water pumping ports 2-16 are tested. The test results are as follows: Figure 3 , Figure 4 shown.

[0032] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for self-scaling and self-sterilization of a circulating cooling water system, characterized in that: An electrochemical electrolysis device is installed on the pipeline (1) of the circulating water system and the water containing chloride ions is converted into H at the anode by using the electrochemical electrolysis device. + and oxidizing chlorine species, and then the water rich in H+ and oxidizing chlorine species is transported to the pipeline (1), The electrochemical electrolysis device (2) comprises an electrolysis unit (2-1) and a power supply for supplying power to the electrolysis unit (2-1); the electrolysis unit (2-1) comprises an anode (2-11) and a cathode (2-12); H-rich + and water with oxidizing chlorine species from near the anode (2-11); The anode (2-11) is a filter electrode, which has a cavity inside and a porous structure on the wall, rich in H + and water containing oxidizing chlorine species is drawn from the interior cavity of the anode (2-11); The cathode (2-12) is a porous mesh tube electrode, and the anode (2-11) is sleeved inside the cathode (2-12); The electrolysis unit (2-1) further comprises an electrolytic cell (2-13), wherein the cathode (2-12) is arranged in the electrolytic cell (2-13); a water inlet (2-14) is arranged at the bottom of the electrolytic cell (2-13), an overflow port (2-15) is arranged at the top, and a fluid for extracting H-rich water from the anode (2-11) is arranged at the top of the anode (2-11). + and oxidizing chlorine species in water bodies (2-16).

2. The method for self-scaling and self-sterilization of a circulating cooling water system according to claim 1, characterized in that: The water used for electrolysis in the electrochemical electrolysis device (2) comes from the circulating water in the pipeline (1).

3. The method for self-scaling and self-sterilization of a circulating cooling water system according to claim 1, characterized in that: The material of the anode (2-11) is a titanium filter element, a titanium oxide filter element or a carbon filter element.

4. The method for self-scaling and self-sterilization of a circulating cooling water system according to claim 1, characterized in that: The cathode (2-12) is made of stainless steel or titanium.

5. The method for self-scaling and self-sterilization of a circulating cooling water system according to claim 1, characterized in that: The distance between the anode (2-11) and the cathode (2-12) is 1-10 cm; the water inlet (2-14) is arranged between the anode (2-11) and the cathode (2-12).

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