Method for inhibiting adhesion of crystal substances on surface of zinc electrodeposition circulating tank

Abstract

The invention relates to a method for inhibiting adhesion of crystals on the surface of a zinc electrodeposition circulating tank, and relates to the technical field of zinc electrodeposition smelting. According to the method for inhibiting the adhesion of the crystals on the surface of the zinc electrodeposition circulating tank, the PP film is adopted as a circulating liquid contact surface, so that the surface energy of the whole chute can be reduced, the contact angle can be increased, the wetting probability and adhesion binding force of the circulating liquid are reduced, and the adhesion of the crystals on the surface of the chute is effectively inhibited; harmful impurities are prevented from entering an electrolytic bath after glass fiber reinforced plastic adherends fall off, and the zinc electrodeposition efficiency and the zinc sheet quality level of follow-up production are guaranteed.

Description

Technical Field

[0001] This application relates to the technical field of zinc electrowinning smelting, and particularly to a method for inhibiting the adhesion of crystalline substances on the surface of a zinc electrowinning circulation tank. Background Art

[0002] In the zinc electrowinning smelting process, the circulating liquid entering and flowing out of the electrolytic cell is often transported by a chute. Due to the strong corrosiveness of the circulating liquid, in order to ensure the mechanical capacity of the chute, fiberglass reinforced plastic is usually used as the material for making the chute.

[0003] However, during the production process, the chute wall will be wetted and adhered after being infiltrated by the circulating liquid, which will affect the flow of the electrolyte. At the same time, some of the shed adherents will be carried into the subsequent production system, affecting the production quality of the product. Among them, the surface adherents of the chute are mainly due to wetting and infiltration phenomena when the circulating liquid flushes the chute wall, resulting in surface adhesion. After adhesion, the circulating liquid crystallizes after cooling, resulting in an increase in the surface energy and contact angle of the glass, a decrease in the surface smoothness, accelerating the wetting phenomenon, and further accelerating the adhesion speed, ultimately forming adherents with a larger thickness.

[0004] To avoid the impact of chute adherents on zinc electrowinning production, it is necessary to regularly clean the chute, resulting in an increase in production costs and also affecting production efficiency. Summary of the Invention

[0005] To solve or partially solve the problems existing in the related technologies, this application provides a method for inhibiting the adhesion of crystalline substances on the surface of a zinc electrowinning circulation tank, which can effectively inhibit the adhesion of crystalline substances on the chute surface, avoid harmful impurities from entering the electrolytic cell after the fiberglass reinforced plastic adherents fall off, and ensure the zinc electrowinning efficiency and the quality level of zinc sheets in subsequent production.

[0006] This application provides a method for inhibiting the adhesion of crystalline substances on the surface of a zinc electrowinning circulation tank, and the method includes the following steps:

[0007] S1: Grinding the fiberglass reinforced plastic chute;

[0008] S2: Gluing the ground fiberglass reinforced plastic chute;

[0009] S3: Laminating the glued fiberglass reinforced plastic chute, wherein the lamination treatment uses a PP film;

[0010] S4: Repeating the gluing treatment and the lamination treatment, and pasting multiple layers of PP films on the chute surface of the overall fiberglass reinforced plastic chute in sequence, so as to reduce the surface energy of the chute surface, increase the contact angle, reduce the wetting probability and adhesion binding force of the circulating liquid, and reduce the adhesion probability of the circulating liquid on the chute surface.

[0011] Optionally, in some embodiments of the present application:

[0012] The fiberglass chute is polished, specifically including:

[0013] Use a angle grinder or other tools to polish the surface of the fiberglass chute so that the surface roughness Ra < 50um;

[0014] Use 240 - 320 mesh sandpaper to polish the surface of the fiberglass chute for a second time so that the surface roughness Ra < 25um.

[0015] Optionally, in some embodiments of the present application:

[0016] The polished fiberglass chute is coated with glue, specifically including:

[0017] Use an adhesive to evenly coat the surface of the polished fiberglass chute, where the coating thickness of the adhesive is 0.03 - 0.05mm.

[0018] Optionally, in some embodiments of the present application:

[0019] The adhesive is GWellmid3010 type adhesive, and the temperature is controlled at 20 - 25°C during application.

[0020] Optionally, in some embodiments of the present application:

[0021] The fiberglass chute after glue coating is laminated, specifically including:

[0022] Paste the prepared PP film on the fiberglass after glue coating and cure for at least 1 hour, where the PP film is made according to the size of the fiberglass chute.

[0023] Optionally, in some embodiments of the present application:

[0024] Repeat the glue coating process and the lamination process, and paste multiple layers of PP films on the fiberglass chute in sequence, specifically including:

[0025] Use an adhesive to evenly coat the surface of the first layer of PP film that has been pasted, and then paste the prepared second layer of PP film on the first layer of PP film;

[0026] After waiting for 1 hour after the second layer of PP film is pasted, paste the next layer of PP film;

[0027] Stop pasting after the total thickness of the sequentially pasted PP films reaches about 2mm, and cure.

[0028] Optionally, in some embodiments of the present application:

[0029] The thickness of the PP film is 0.5 mm, and 4 layers of PP film are pasted on the surface of the fiberglass chute.

[0030] Optionally, in some embodiments of the present application:

[0031] After all the PP films are pasted, the curing time for curing is at least 24 hours or more.

[0032] The technical solution provided by the present application may include the following beneficial effects:

[0033] By using the PP film as the contact surface of the circulating liquid in the present application, the surface energy of the overall chute can be reduced and the contact angle can be increased, thereby reducing the wetting probability and adhesion bonding force of the circulating liquid, effectively inhibiting the adhesion of crystalline substances on the chute surface, avoiding the entry of harmful impurities into the electrolytic cell after the adhesion of fiberglass adherents falls off, and ensuring the zinc electrowinning efficiency and the quality level of zinc sheets in subsequent production.

[0034] By sequentially pasting PP films on the surface of the fiberglass chute in the present application, after the total pasted thickness reaches 2 mm, the influence of the surface roughness of the fiberglass chute on the surface PP film is reduced, and the smoothness of the surface PP film after pasting can be ensured, so as to effectively reduce the adhesion probability of the circulating liquid on the tank wall surface. Moreover, the method of pasting each layer in sequence can ensure the pasting bonding strength of the PP film and avoid the situation of falling off.

[0035] By performing two grinding treatments in the present application, the surface roughness of the fiberglass chute can be effectively reduced, microscopic pits and protrusions can be reduced, the adhesive can be evenly spread, bubbles and voids can be reduced, and the subsequent bonding strength of the PP film can be ensured.

[0036] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] By describing the exemplary embodiments of the present application in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present application will become more obvious. Among them, in the exemplary embodiments of the present application, the same reference numerals generally represent the same components.

[0038] Figure 1 It is a schematic structural diagram of a method for inhibiting the adhesion of crystalline substances on the surface of a zinc electrowinning circulation tank in an embodiment of the present application;

[0039] Figure 2 It is a schematic diagram of the tension of the contact angle at each interface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present application will be more thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0041] It should be understood that although the terms "first", "second", "third", etc. may be used in the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0042] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0043] Unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0044] During the production process, the chute wall will be wetted and adhered after being infiltrated by the circulating liquid, which will affect the flow of the electrolyte, and at the same time, some of the detached adhesives will be brought into the subsequent production system, affecting the production quality of the product. Among them, the surface adhesives on the chute are mainly due to the wetting and infiltration phenomena that occur when the circulating liquid flushes the chute wall, resulting in surface adhesion. After the adhered circulating liquid cools, crystallization occurs, causing the glass surface energy and contact angle to increase, and the surface smoothness to decrease, resulting in an acceleration of the wetting phenomenon and an acceleration of the adhesion speed, and finally forming a relatively thick adhesive.

[0045] To avoid the impact of chute adhesives on zinc electrowinning production, it is necessary to regularly clean the chute, which increases production costs and also affects production efficiency.

[0046] In view of the above problems, the embodiment of the present application provides a method for suppressing the adhesion of crystallized substances on the surface of the zinc electrowinning circulation tank, which can effectively suppress the adhesion of crystallized substances on the chute surface, avoid harmful impurities from entering the electrolytic cell after the FRP adhesives fall off, and ensure the zinc electrowinning efficiency and zinc sheet quality level of subsequent production.

[0047] The technical solutions of the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0048] Figure 1 It is a schematic structural diagram of the method for suppressing the adhesion of crystallized substances on the surface of the zinc electrowinning circulation tank in the embodiment of the present application.

[0049] See Figure 1 , a method for suppressing the adhesion of crystallized substances on the surface of the zinc electrowinning circulation tank, the method comprising the following steps:

[0050] S1: Grind the FRP chute.

[0051] Specifically, use a angle grinder or other tools to grind the surface of the FRP chute so that the surface roughness Ra < 50um;

[0052] Use 240 - 320 mesh sandpaper to secondarily grind the surface of the FRP chute so that the surface roughness Ra < 25um.

[0053] In this embodiment, by performing two grinding treatments, the surface roughness of the FRP chute can be effectively reduced, micro pits and protrusions can be reduced, the adhesive can be evenly spread, bubbles and voids can be reduced, and the bonding strength of the subsequent PP film can be ensured.

[0054] S2: Apply glue to the ground FRP chute.

[0055] Specifically, use an adhesive to evenly coat the surface of the ground FRP chute, wherein the coating thickness of the adhesive is 0.03 - 0.05mm.

[0056] Specifically, the adhesive is a GWellmid3010 type adhesive, and the temperature is controlled at 20 - 25°C during application.

[0057] In this embodiment, the GWellmid3010 type adhesive has certain acid resistance and good bonding performance. By using the GWellmid3010 type adhesive, the PP film can be well bonded to the surface of the FRP chute and the bonding strength can be ensured.

[0058] S3: Perform film covering treatment on the FRP chute after glue coating treatment, where the film covering treatment uses a PP film.

[0059] Specifically, paste the fabricated PP film on the FRP after glue coating treatment and cure for at least 1 hour, where the PP film is fabricated according to the size of the FRP chute.

[0060] S4: Repeat the glue coating treatment and film covering treatment, and paste multiple layers of PP films on the upper part of the FRP chute in sequence, so that the surface energy of the overall FRP chute decreases, the contact angle increases, the wetting probability of the circulating liquid decreases, the adhesion binding force decreases, and the adhesion probability of the circulating liquid on the chute surface decreases.

[0061] In this embodiment, the surface adhesion of the FRP chute is mainly due to the wetting and immersion phenomena occurring when the circulating liquid scours the tower wall, resulting in surface adhesion. After the adhered circulating liquid cools, crystallization occurs, leading to an increase in the glass surface energy and contact angle, and a decrease in the surface smoothness, causing the wetting to accelerate further and the adhesion speed to accelerate further, ultimately forming a relatively thick adhesion layer. And wetting, immersion, and adhesion are related to the following factors:

[0062] 1. The wetting phenomenon is related to the contact angle

[0063] The occurrence of the wetting phenomenon is highly related to the contact angle between the liquid phase and the solid phase and the solid surface energy. Among them, the contact angle is determined by the Young's equilibrium formula (1) published in 1805 ( Figure 2 is a schematic diagram of the contact angle of each interface with the tension in this embodiment of the application, as Figure 2 shown), and this equilibrium formula is shown in Formula 1. When θ is larger, the wetting process is more likely to occur. When θ < 90°, it is wetting. When θ ≥ 90°, wetting does not occur;

[0064] γ sg =γ sl +γl 1g cosθ (1)

[0065] In the formula: γsg, γsl, and γlg respectively represent the tensions of the solid-liquid, liquid-solid, and liquid-gas interfaces.

[0066] 2. The degree of immersion is related to the smoothness of the chute surface in contact with the circulating liquid

[0067] According to the Wenzel formula (2), the smaller the surface roughness, the smoother the surface, and the less likely it is to adhere;

[0068] rcosθ = cosθ` (2)

[0069] In the formula: r is the surface roughness. The smoother the surface, the smaller r is, and θ` is the apparent contact angle.

[0070] 3. The adhesion of the chute surface by the circulating liquid is related to the surface energy of the material.

[0071] Similar to the liquid surface, the atoms or molecules on the solid surface are different from those in the bulk phase and will be subjected to an inward gravitational force, which is the root cause of the generation of the solid surface energy. The size of the contact angle is also closely related to the surface energy. The solid surface energy, especially the high-energy solid surface energy, spontaneously adsorbs certain components from the surrounding environment to reduce the surface energy, resulting in a decrease in the contact angle. Therefore, the larger the solid surface energy, the more conducive it is to the spreading of the liquid.

[0072] 4. The degree of adhesion of the chute is related to the work of adhesion.

[0073] Under isobaric and isothermal conditions, when the work of adhesion WA is larger, the liquid can better wet the solid, and the liquid-solid combination is stronger.

[0074] Since the θ of the PP material is large, it can be seen from formula (1) that the γsg tension is small, so WA is small. The circulating liquid is less likely to wet the PP. Even if the circulating liquid wets the PP material, due to the weak solid-liquid combination, when the crystal content reaches a certain level during use, it will fall off automatically under the action of gravity.

[0075] w A =γ sg +γ 1g -γ sl (3)

[0076] The surface energy of the PP material is 32.16 ± 0.83 (mJ·m-2). Compared with the glass fiber reinforced plastic, the surface energy is lower, belonging to low-energy substances; at the same time, the surface of the PP material film is smoother, the contact angle of the PP is θ = 95 - 100°, which is greater than 90°, and it is difficult for the circulating liquid to wet its surface; secondly, the bonding performance between the PP and the glass fiber reinforced plastic is good, with high wear resistance and high mechanical properties including tensile strength, compressive strength, and flexural fatigue performance, and good chemical stability. Except for being corroded by concentrated sulfuric acid and concentrated nitric acid, it is relatively stable to other various chemical reagents.

[0077] In summary, by using the PP film as the contact surface of the circulating liquid in this application, the surface energy of the overall chute can be reduced and the contact angle can be increased, thereby reducing the wetting probability and adhesion bonding force of the circulating liquid, effectively inhibiting the adhesion of crystalline substances on the chute surface, avoiding the entry of harmful impurities into the electrolytic cell after the adhesion of the glass fiber reinforced plastic falls off, and ensuring the zinc electrowinning efficiency and the quality level of zinc sheets in subsequent production.

[0078] Specifically, an adhesive is evenly applied to the surface of the first-layer PP film that has been pasted well, and then the made second-layer PP film is pasted on the first-layer PP film.

[0079] After 1 hour of pasting the second layer of PP film, paste the next layer of PP film;

[0080] After the total thickness of the sequentially pasted PP films reaches about 2 mm, stop pasting and perform curing.

[0081] Specifically, the thickness of the PP film is 0.5 mm, and 4 layers of PP films are pasted on the surface of the fiberglass chute.

[0082] Specifically, after all the PP films are pasted, the curing time for curing is at least 24 hours or more. By curing for 24 hours, the bonding strength after the PP film is pasted can be ensured.

[0083] In this embodiment, by sequentially pasting PP films on the surface of the fiberglass chute, after the total pasted thickness reaches 2 mm, the influence of the surface roughness of the fiberglass chute on the surface PP film is reduced, and the smoothness of the surface PP film after pasting can be ensured, so as to effectively reduce the adhesion probability of the circulating liquid on the tank wall surface. Moreover, the method of pasting each layer in sequence can ensure the pasting bonding strength of the PP film and avoid the situation of peeling off.

[0084] The technical solutions provided in the embodiments of the present application include the following beneficial effects:

[0085] By using the PP film as the contact surface of the circulating liquid in the present application, the surface energy of the overall chute can be decreased and the contact angle can be increased, thereby reducing the wetting probability and adhesion bonding force of the circulating liquid, effectively inhibiting the adhesion of crystalline substances on the chute surface, avoiding harmful impurities from entering the electrolytic cell after the adhesion of fiberglass adherents falls off, and ensuring the zinc electrowinning efficiency and zinc sheet quality level in subsequent production.

[0086] By sequentially pasting PP films on the surface of the fiberglass chute in the present application, after the total pasted thickness reaches 2 mm, the influence of the surface roughness of the fiberglass chute on the surface PP film is reduced, and the smoothness of the surface PP film after pasting can be ensured, so as to effectively reduce the adhesion probability of the circulating liquid on the tank wall surface. Moreover, the method of pasting each layer in sequence can ensure the pasting bonding strength of the PP film and avoid the situation of peeling off.

[0087] By performing two grinding treatments in the present application, the surface roughness of the fiberglass chute can be effectively reduced, microscopic pits and protrusions can be reduced, the adhesive can be evenly spread, bubbles and voids can be reduced, and the bonding strength of the subsequent PP film can be ensured.

[0088] Finally, it should also be noted that in this text, relationships such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "including", "comprising" or any other variant are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0089] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed over multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0090] In addition, each functional unit in the various embodiments of the present application may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit. The above integrated units may be implemented in the form of hardware or in the form of software functional units.

[0091] The various embodiments of the present application have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skilled persons in the technical field to understand the embodiments disclosed herein.

Claims

1. A method for inhibiting the adhesion of crystalline substances on the surface of a zinc electrowinning circulation tank, characterized in that, The method includes the following steps: S1: Grinding the fiberglass chute; S2: Gluing the ground fiberglass chute; S3: Laminating the glued fiberglass chute with a PP film, where the lamination is performed using a PP film; S4: Repeating the gluing and laminating processes to paste multiple layers of PP film on the chute surface of the overall fiberglass chute in sequence, so as to reduce the surface energy of the chute surface of the fiberglass chute, increase the contact angle, reduce the wetting probability, decrease and adhesion bonding force of the circulating liquid, and reduce the adhesion probability of the circulating liquid on the chute surface.

2. The method for inhibiting the adhesion of crystalline substances on the surface of the zinc electrowinning circulation tank according to claim 1, wherein: The grinding treatment of the fiberglass chute specifically includes: Using a angle grinder or other tools to grind the surface of the fiberglass chute to make its surface roughness Ra < 50um; using 240 - 320 mesh sandpaper to perform secondary grinding on the surface of the fiberglass chute to make its surface roughness Ra < 25um.

3. The method for suppressing the adhesion of crystallized substances on the surface of a zinc electrowinning circulation tank according to claim 2, wherein: The gluing treatment of the ground fiberglass chute specifically includes: Using an adhesive to evenly coat the surface of the ground fiberglass chute, where the coating thickness of the adhesive is 0.03 - 0.05mm.

4. The method for suppressing the adhesion of crystallized substances on the surface of a zinc electrowinning circulation tank according to claim 3, wherein: The adhesive is a GWellmid3010 type adhesive, and the temperature during coating is controlled at 20 - 25°C.

5. The method for suppressing the adhesion of crystallized substances on the surface of a zinc electrowinning circulation tank according to claim 4, wherein: The lamination treatment of the glued fiberglass chute specifically includes: Pasting the prepared PP film on the glued fiberglass and curing for at least 1 hour, where the PP film is made according to the size of the fiberglass chute.

6. The method for suppressing the adhesion of crystallized substances on the surface of a zinc electrowinning circulation tank according to any one of claims 1 or 5, wherein: The repeated gluing and lamination processes to paste multiple layers of PP film on the chute surface of the fiberglass chute in sequence specifically include: Using an adhesive to evenly coat the surface of the first layer of PP film that has been pasted, and then pasting the prepared second layer of PP film on the first layer of PP film; After waiting for 1 hour after the second layer of PP film is pasted, paste the next layer of PP film; Stop pasting after the total thickness of the sequentially pasted PP films reaches about 2mm, and perform curing.

7. The method for suppressing the adhesion of crystallized substances on the surface of a zinc electrowinning circulation tank according to claim 6, wherein: The thickness of the PP film is 0.5mm, and 4 layers of PP film are pasted on the surface of the fiberglass chute.

8. The method for suppressing the adhesion of crystallized substances on the surface of a zinc electrowinning circulation tank according to claim 7, wherein: After all the PP films are pasted, the curing time for curing is at least 24 hours or more.

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