Fluorine-containing waste acid treatment device
By adding lime emulsion, liquid alkali, lime powder and PAM in the neutralization reactor, combined with the filter press and evaporation mechanism, the flocculation and evaporation problems in fluorine-containing waste acid treatment are solved, and the efficient waste acid treatment effect is achieved.
Patent Information
- Application Number
- CN202422267937.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-09-14
AI Technical Summary
In the prior art, fluorine-containing waste acid treatment is difficult to flocculate. After filtration, the sludge has high moisture content, the fluorine content in the pressed filtrate, and the high salt content, which leads to difficulties in handling.
By adding lime emulsion, liquid alkali, lime powder and PAM to the neutralizing reaction kettle, flocculation precipitation is formed, and the filter press and evaporation mechanism is used for processing, including a combination of the neutralizing reaction kettle, a filter press and an evaporation mechanism.
Effective flocculation and evaporation treatment of fluorine-containing waste acid is achieved, the fluorine content and moisture in the pressed filtrate are reduced, the wastewater generation is reduced, and the treatment effect and the overall efficiency of the system are improved.
Smart Images
Figure CN223255066U_ABST
Abstract
Description
Technical Field
[0001] This specification relates to the technical field of waste acid treatment, and specifically to a fluorine-containing waste acid treatment device. Background Art
[0002] The integrated circuit production process generates a large amount of fluorinated waste acid. This fluorinated waste acid, containing significant amounts of nitric acid and other small amounts of organic matter, requires harmless treatment. Current treatment methods for fluorinated waste acid face challenges, including difficulty in flocculation, high moisture content in the sludge after filter pressing, and high fluoride and salinity levels in the filtrate. This makes the treatment of fluorinated waste acid complex. Summary of the Invention
[0003] In view of this, the embodiment of this specification provides a fluorine-containing waste acid treatment device. By adding lime milk, liquid alkali, slaked lime powder and PAM into the neutralization reactor in sequence, the fluorine-containing waste acid can form a flocculated precipitate, which is convenient for the subsequent filter press operation. The fluorine-containing waste acid after the neutralization reaction is filter-filtered by a first filter press, and the fluorine-containing waste liquid after the filter press is evaporated by an evaporation mechanism to ensure the treatment effect.
[0004] The embodiments of this specification provide the following technical solutions: a fluorine-containing waste acid treatment device, comprising a neutralization reactor, a filter press mechanism, and an evaporation mechanism connected in sequence through pipelines;
[0005] The neutralization reactor is connected to a fluorine-containing waste acid inlet pipeline, and is also connected to a lime milk pipeline, a liquid caustic soda pipeline and a PAM pipeline;
[0006] The filter press mechanism includes a first filter press, a filter cake collecting portion and a transfer tank, wherein the first filter press is connected to the neutralization reactor via a pipeline, and the first filter press is connected to the transfer tank via a pipeline;
[0007] The evaporation mechanism is connected to the first filter press through a pipeline, and the evaporation mechanism evaporates the fluorine-containing waste liquid filtered by the filter press mechanism.
[0008] Preferably, the evaporation mechanism includes a feed tank, a bag filter, a preheater, a heat exchanger, a separator, a thickener, a second filter press and a mother liquid tank, the feed tank is connected to the transfer tank through a pipeline, the feed tank, bag filter, preheater, separator, thickener, second filter press and mother liquid tank are connected in sequence through pipelines, the second filter press is connected to the transfer tank, and the heat exchanger and the separator are connected through a pipeline.
[0009] Preferably, the evaporation mechanism further includes a condenser and a distillate water tank, the condenser and the separator are connected via a pipeline, and the distillate water tank and the condenser are connected via a pipeline.
[0010] Preferably, the second filter press is a small plate and frame filter press.
[0011] Preferably, the evaporation mechanism is a titanium device.
[0012] Preferably, the neutralization reactor is further provided with a stirring motor, the output end of the stirring motor is connected to a stirring rod, and the stirring rod is arranged inside the neutralization reactor.
[0013] Preferably, the neutralization reactor is further provided with a feeding port, and the feeding port is used to add slaked lime powder into the neutralization reactor.
[0014] Preferably, the first filter press is a plate and frame filter press.
[0015] Preferably, the filter cake collecting part includes an open ton barrel, and the open ton barrel is located directly below the plate and frame filter press.
[0016] Preferably, the neutralization reactor is lined with polytetrafluoroethylene material.
[0017] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:
[0018] By sequentially adding lime milk and liquid alkali into the neutralization reactor, the solution will exhibit colloidal properties and will not be able to flocculate. Slaked lime powder is then added again to adsorb small particle precipitation in the solution, thereby achieving the effect of destroying the colloid. The subsequent addition of PAM can cause the fluorine-containing waste acid to form flocculated precipitation, facilitating subsequent filter pressing operations. The fluorine-containing waste acid after the neutralization reaction is filter-pressed by the first filter press, and the fluorine-containing waste liquid after the filter pressing is evaporated by the evaporation mechanism, thereby ensuring treatment effects, a high degree of integration, low emissions, and low wastewater generation. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0020] Figure 1 It is a structural schematic diagram of the neutralization reactor of the fluorine-containing waste acid treatment device provided in this application;
[0021] Figure 2 This is a structural schematic diagram of the filter press mechanism of the fluorine-containing waste acid treatment device provided in this application;
[0022] Figure 3 It is a structural schematic diagram of the evaporation mechanism of the fluorine-containing waste acid treatment device provided in this application.
[0023] In the figure, 1. Neutralization reactor; 101. Fluorine-containing waste acid inlet pipeline; 102. Liquid alkali pipeline; 103. PAM pipeline; 104. Stirring motor; 105. Stirring rod; 2. First filter press; 3. Filter cake collection part; 4. Transfer tank; 5. Feed tank; 6. Bag filter; 7. Preheater; 8. Heat exchanger; 9. Separator; 10. Condenser; 11. Distillate water tank; 12. Thickener; 13. Second filter press; 14. Mother liquor tank. DETAILED DESCRIPTION
[0024] The embodiments of the present application are described in detail below with reference to the accompanying drawings.
[0025] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.
[0026] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.
[0027] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.
[0028] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples. However, one skilled in the art will appreciate that the aspects described can be practiced without these specific details.
[0029] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.
[0030] like Figure 1-Figure 3 As shown, a fluorine-containing waste acid treatment device includes a neutralization reactor 1, a filter press mechanism and an evaporation mechanism connected in sequence through pipelines;
[0031] The neutralization reactor 1 is connected to a fluorine-containing waste acid inlet pipe 101, and is also connected to a lime milk pipe, a liquid caustic soda pipe 102, and a PAM (polyacrylamide) pipe 103. A circulating water pipe is also provided on the side of the neutralization reactor 1.
[0032] The filter press mechanism includes a first filter press 2, a filter cake collecting part 3 and a transfer tank 4, wherein the first filter press 2 is connected to the neutralization reactor 1 through a pipeline, and the first filter press 2 is connected to the transfer tank 4 through a pipeline;
[0033] The evaporation mechanism is connected to the first filter press 2 via a pipeline, and the evaporation mechanism evaporates the fluorine-containing waste liquid filtered by the filter press mechanism.
[0034] Fluorine-containing waste acid enters the neutralization reactor 1 through the fluorine-containing waste acid inlet pipe, and slaked lime and water are mixed into lime milk and then added to the neutralization reactor 1. After the reaction is completed, liquid alkali is added to adjust the pH to neutral. At this time, the solution will show colloidal properties and cannot flocculate. Slaked lime powder is added again to adsorb small particle precipitation in the solution to achieve the effect of destroying the colloid. PAM (polyacrylamide) is added for further flocculation and precipitation, which helps to reduce the moisture in the filter cake as much as possible in the subsequent filter press step, and can also further reduce the fluorine content of the filtrate. The fluorine-containing waste acid after the neutralization reaction is filtered by the first filter press 2, and the filter cake collection part 3 collects the filter cake formed by the filter press. The solution after the filter press enters the transfer tank 4 and flows to the evaporation mechanism through the transfer tank 4. The fluorine-containing waste liquid after the filter press is evaporated by the evaporation mechanism to ensure the treatment effect.
[0035] It should be noted that the filtrate contains a large amount of total nitrogen, which is difficult for the biochemical system to treat, resulting in substandard wastewater discharge. If incinerated, the excessive salt content will cause severe salt accumulation and blockage in the incineration system, necessitating evaporation. Compared to direct biochemical treatment, evaporation of the filtrate can reduce the pressure in the biochemical system and increase the overall system processing capacity. It is also less expensive than incineration and does not affect equipment.
[0036] like Figure 3 As shown, in some embodiments, the evaporation mechanism includes a feed tank 5, a bag filter 6, a preheater 7, a heat exchanger 8, a separator 9, a thickener 12, a second filter press 13 and a mother liquid tank 14, the feed tank 5 is connected to the transfer tank 4 through a pipeline, the feed tank 5, the bag filter 6, the preheater 7, the separator 9, the thickener 12, the second filter press 13 and the mother liquid tank 14 are connected in sequence through pipelines, the second filter press 13 is connected to the transfer tank 4, The heat exchanger 8 is connected to the separator 9 by a pipeline. After filtration by the first filter press 2, the filtrate enters the feed tank 5, passes through the bag filter 6, enters the preheater 7, and enters the separator 9 after preliminary heating in the preheater 7. It is heated in the circulation process of the separator 9 and the heat exchanger 8. After evaporation is completed, the slurry enters the thickener 12 to prepare for solid-liquid separation. After passing through the thickener 12, the slurry enters the second filter press 13, and the concentrated liquid re-enters the transfer tank 4, and the filter cake is landfilled.
[0037] like Figure 3 As shown, in some embodiments, the evaporation mechanism further includes a condenser 10 and a distillate water tank 11. The condenser 10 and the separator 9 are connected by a pipeline, and the distillate water tank 11 is connected to the condenser 10 by a pipeline. The distillate water generated during the evaporation process passes through the condenser 10 and enters the distillate water tank 11. At this time, the temperature of the distillate water is still relatively high. The distillate water enters the preheater 7 and is discharged into the wastewater station.
[0038] like Figure 3 As shown, in some embodiments, the second filter press 13 is a small plate and frame filter press. The small plate and frame filter press adopts a pressure filtration method, which can quickly and effectively remove impurities and particulate matter in the liquid, and has high filtration efficiency and precision. At the same time, the small plate and frame filter press can form a relatively dense filter cake layer, effectively blocking the passage of liquid, thereby obtaining a lower filter cake moisture content.
[0039] like Figure 3 As shown, in some embodiments, the evaporation mechanism is a titanium device. The use of titanium equipment for the evaporation mechanism can prevent the filter press from corroding the equipment.
[0040] like Figure 1 As shown, in some embodiments, the neutralization reactor 1 is further provided with a stirring motor 104, and the output end of the stirring motor 104 is connected to a stirring rod 105, and the stirring rod 105 is arranged inside the neutralization reactor 1. The stirring motor 104 is arranged on the top of the neutralization reactor 1, and the stirring motor 104 drives the stirring rod 105 to rotate, and the stirring rod 105 stirs the solution inside the neutralization reactor 1. The stirring motor 104 is in a normally open state, which can prevent the pipeline from being blocked and accelerate the reaction efficiency.
[0041] like Figure 1 As shown, in some embodiments, the neutralization reactor 1 is further provided with a feeding port, which is used to add slaked lime powder into the neutralization reactor 1. By providing a feeding port for adding slaked lime powder on the neutralization reactor 1, the slaked lime powder can absorb small particles in the solution and precipitate, thereby achieving the effect of destroying the colloid.
[0042] like Figure 2 As shown, in some embodiments, the first filter press 2 is a plate and frame filter press. The plate and frame filter press adopts a pressure filtration method, which can quickly and effectively remove impurities and particulate matter in the liquid, and has high filtration efficiency and precision. The filter plates and other components of the plate and frame filter press usually have good corrosion resistance and can adapt to the environment of various corrosive media to ensure the long-term stable operation of the equipment. The secondary extrusion filter cake technology adopted by the plate and frame filter press significantly reduces the moisture content of the filter cake after filtration.
[0043] like Figure 2 As shown, in some embodiments, the filter cake collecting part 3 includes an open ton barrel, which is located directly below the plate and frame filter press. By arranging the open ton barrel directly below the plate and frame filter press, the filter cake can be collected, which facilitates the subsequent burial of the filter cake.
[0044] like Figure 1 As shown, in some embodiments, the neutralization reactor 1 is lined with polytetrafluoroethylene material. The neutralization reactor 1 is lined with polytetrafluoroethylene material, which has extremely strong corrosion resistance and can resist the erosion of most chemical substances, including strong acids, strong alkalis, organic solvents, etc.
[0045] The following example illustrates the treatment process of fluorine-containing waste acid:
[0046] The feedstock contains fluorine content of 158,500 mg / l and acidity of 12.4 mmol / g. 3 tons of fluorine-containing waste acid are added to 1 t of dilution water. 0.9 tons of slaked lime are then added to the dilution water in the 3 t transfer tank to make lime milk. This is then added to the neutralization reaction tank, stirred and refluxed for 3 hours. 0.4 tons of liquid caustic soda are added to neutralize the pH. The reaction is continued for 1 hour. 0.3 tons of slaked lime are then added and stirred thoroughly. After flocculation, 0.8 tons of 2‰ PAM solution is added. After flocculation, the filtrate is filtered, evaporated, and the filter cake landfilled. After this process, the fluorine content in the filtrate is reduced to 12.5 mg / l, the moisture content in the filter cake is 34%, and the evaporated distillate contains 158 mg / l of COD, 21.45 mg / l of ammonia nitrogen, and 49.07 mg / l of total nitrogen, making it suitable for biochemical wastewater treatment. After the concentrated liquid passes through the small plate and frame filter press, the filtrate re-enters the transfer tank to be used for slaked lime to make lime milk or dilute the raw material liquid. The filter cake has a moisture content of 14% and is landfilled together with the previous filter cake.
[0047] The same or similar parts between the various embodiments in this specification can be referred to in conjunction with each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiments described later, since they correspond to the system, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.
[0048] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.
Claims
1. A fluorine-containing waste acid treatment device, characterized in that: It includes a neutralization reaction kettle, a filter press mechanism and an evaporation mechanism connected in sequence through pipelines; The neutralization reactor is connected to a fluorine-containing waste acid inlet pipeline, and is also connected to a lime milk pipeline, a liquid caustic soda pipeline and a PAM pipeline; The filter press mechanism includes a first filter press, a filter cake collecting portion and a transfer tank, wherein the first filter press is connected to the neutralization reactor via a pipeline, and the first filter press is connected to the transfer tank via a pipeline; The evaporation mechanism is connected to the first filter press through a pipeline, and the evaporation mechanism evaporates the fluorine-containing waste liquid filtered by the filter press mechanism.
2. The fluorine-containing waste acid treatment device according to claim 1, characterized in that: The evaporation mechanism includes a feed tank, a bag filter, a preheater, a heat exchanger, a separator, a thickener, a second filter press and a mother liquid tank. The feed tank is connected to the transfer tank through a pipeline. The feed tank, bag filter, preheater, separator, thickener, second filter press and mother liquid tank are connected in sequence through pipelines. The second filter press is connected to the transfer tank, and the heat exchanger and separator are connected through a pipeline.
3. The fluorine-containing waste acid treatment device according to claim 2, characterized in that: The evaporation mechanism further includes a condenser and a distillate water tank. The condenser and the separator are connected via a pipeline, and the distillate water tank is connected to the condenser via a pipeline.
4. The fluorine-containing waste acid treatment device according to claim 2, characterized in that: The second filter press is a small plate and frame filter press.
5. The fluorine-containing waste acid treatment device according to any one of claims 1 to 4, characterized in that: The evaporation mechanism is a titanium device.
6. The fluorine-containing waste acid treatment device according to claim 1, characterized in that: The neutralization reactor is further provided with a stirring motor, an output end of the stirring motor is connected to a stirring rod, and the stirring rod is arranged inside the neutralization reactor.
7. The fluorine-containing waste acid treatment device according to claim 1 or 6, characterized in that: The neutralization reactor is also provided with a feeding port, which is used to add slaked lime powder into the neutralization reactor.
8. The fluorine-containing waste acid treatment device according to claim 1, characterized in that: The first filter press is a plate and frame filter press.
9. The fluorine-containing waste acid treatment device according to claim 8, characterized in that: The filter cake collecting part includes an open ton barrel, and the open ton barrel is located directly below the plate and frame filter press.
10. The fluorine-containing waste acid treatment device according to claim 1, characterized in that: The neutralization reactor is lined with polytetrafluoroethylene material.