A continuous potassium fluoride crystallization device

Abstract

The utility model relates to a kind of potassium fluoride continuous crystallization device, belong to chemical crystallization device technical field.It includes primary evaporator and secondary evaporator;Primary evaporator includes primary heater and primary separator;The material import of primary separator is communicated with the material export of primary heater;The material export of primary separator is communicated with the material import of primary heater by primary circulating pump;Primary heater is provided with steam inlet and condensate outlet;Secondary evaporator includes secondary heater, secondary separator and crystallizer;The material import of secondary heater is also communicated with the material export of primary separator by material transfer pump;The steam export of primary separator is communicated with the steam import of secondary heater;The material export of secondary heater is communicated with the material import of secondary separator;The material export of secondary separator is communicated with crystallizer;The secondary steam export of secondary separator is communicated with condenser;Secondary separator is communicated with the material import of secondary heater by secondary circulating pump.

Description

Technical Field

[0001] This utility model relates to a continuous potassium fluoride crystallization device, belonging to the technical field of chemical crystallization devices. Background Technology

[0002] Potassium fluoride is a white crystalline powder, easily hygroscopic, and widely used in glass engraving, food preservation, and electroplating industries as a fluorinating agent for organic compounds, a welding flux, and a catalyst. Currently, the mainstream industrial production method involves evaporating a low-concentration potassium fluoride solution to obtain a high-concentration solution, which is then pumped into a spray drying tower for drying and crystallization to produce active potassium fluoride products with particle sizes ranging from tens to hundreds of micrometers. This product is suitable for industries such as the fluorination of organic compounds. The exhaust gas from the spray drying tower is subjected to multi-stage cyclone dust removal and water film dust removal before being discharged at high altitude.

[0003] shortcoming: Potassium fluoride produced by spray drying towers typically has extremely small particle sizes, making it suitable for industries such as fluorinating agents. However, for other industries with lower activity requirements, this product has disadvantages such as easy moisture absorption due to its small particle size, tendency to clump during long-distance transportation, low bulk density, and high transportation costs. Furthermore, the spray drying process has drawbacks such as high energy consumption, the need for multi-stage dust removal systems for drying tower exhaust gas, and significant environmental pollution. Utility Model Content

[0004] The purpose of this invention is to provide a potassium fluoride continuous crystallization apparatus to solve the above-mentioned technical problems.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A potassium fluoride continuous crystallization apparatus includes a primary evaporator and a secondary evaporator; the primary evaporator includes a primary heater and a primary separator; the material inlet of the primary separator is connected to the material outlet of the primary heater; the material outlet of the primary separator is connected to the material inlet of the primary heater via a primary circulating pump; the primary heater is provided with a steam inlet and a condensate outlet; The secondary evaporator includes a secondary heater and a secondary separator; the material outlet of the primary separator is also connected to the material inlet of the secondary heater via a transfer pump; the steam outlet of the primary separator is connected to the steam inlet of the secondary heater; and the material outlet of the secondary heater is connected to the material inlet of the secondary separator. The material outlet of the secondary separator is connected to the crystallizer; the secondary steam outlet of the secondary separator is connected to the condenser; and the secondary separator is connected to the material inlet of the secondary heater via a secondary circulation pump.

[0006] A further improvement to the technical solution of this utility model is as follows: the crystal slurry outlet of the crystallizer is connected to the crystal slurry inlet of the thickener via a discharge pump; the discharge port of the thickener is connected to a centrifuge; the clear liquid outlet of the thickener is connected to a mother liquor tank; and the clear liquid outlet of the centrifuge is connected to a mother liquor tank.

[0007] A further improvement to the technical solution of this utility model is that the outlet of the mother liquor tank is connected to the crystallizer through a mother liquor pump.

[0008] A further improvement to the technical solution of this utility model is as follows: the condensate outlet of the condensing equipment is connected to the condensate tank; the condensate outlet of the secondary heater is connected to the condensate tank; and a condensate pump is installed connected to the condensate outlet of the condensate tank.

[0009] A further improvement to the technical solution of this utility model is that the condensing equipment is an evaporative condenser, and the gas outlet of the evaporative condenser is connected to a vacuum pump; or the condensing equipment adopts the form of a condenser plus a cooling tower.

[0010] A further improvement to the technical solution of this utility model is that the crystallizer is an OSLO crystallizer.

[0011] A further improvement to this utility model is that it also includes a multi-stage evaporator configured according to the evaporation rate. Due to the adoption of the above technical solution, the technical effects achieved by this utility model are as follows: This invention relates to a continuous potassium fluoride crystallization device. The main equipment of this device adopts a multi-effect design, allowing for multiple uses of steam. Compared to spray drying towers, which only utilize the heat source once before discharging it from the system, this significantly reduces production energy consumption. The device uses an evaporative condenser, which further reduces system operating energy consumption compared to traditional condensers.

[0012] The potassium fluoride continuous crystallization device of this invention uses an OSLO crystallizer, which is conducive to crystal growth, can more easily cultivate larger crystals, significantly reduces the product's moisture absorption and agglomeration rate, and has a higher product bulk density, thus reducing transportation and usage costs.

[0013] The evaporation condensate of the discharge system of this invention can be returned to the front-end batching process for reuse, and only a small amount of non-condensable gas is discharged from the system, resulting in minimal environmental pollution. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; The components are as follows: 1. Primary heater; 2. Primary separator; 3. Primary circulation pump; 4. Transfer pump; 5. Secondary heater; 6. Secondary separator; 7. Crystallizer; 8. Secondary circulation pump; 9. Discharge pump; 10. Thickener; 11. Centrifuge; 12. Mother liquor tank; 13. Mother liquor pump; 14. Condensation equipment; 15. Vacuum pump; 16. Condensate tank; 17. Condensate pump. Detailed Implementation

[0015] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0016] In the description of this utility model, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0017] This invention relates to a continuous potassium fluoride crystallization apparatus, which is used to crystallize potassium fluoride solutions.

[0018] This device employs multi-effect evaporation, specifically double-effect evaporation. It mainly consists of a primary evaporator and a secondary evaporator. The material is sequentially concentrated through high-flow-rate circulation in both the primary and secondary evaporators.

[0019] like Figure 1 As shown, the primary evaporator includes a primary heater 1 and a primary separator 2. The primary heater 1 has a material inlet, a material outlet, a steam inlet, and a condensate outlet; the material enters the primary heater 1, and high-temperature steam also enters the primary heater 1 to heat the material.

[0020] The material outlet of the primary heater 1 is connected to the material inlet of the primary separator 2 via a pipeline. The heated material enters the primary separator 2. In the primary separator, the material boils and generates secondary steam, thus concentrating the material. The material outlet of the primary separator 2 is connected to the material inlet of the primary heater 1 via a primary circulation pump 3 and a pipeline, allowing the material to circulate and concentrate between the primary heater 1 and the primary separator 2. After concentration, the remaining material is sent to the secondary evaporator. The material concentrated in the primary evaporator then enters the secondary evaporator for secondary evaporation and concentration.

[0021] The secondary evaporator includes a secondary heater 5 and a secondary separator 6. The material outlet of the primary separator 2 is also connected to the material inlet of the secondary heater 5 via a transfer pump 4 and a pipeline. The steam outlet of the primary separator 2 is connected to the steam inlet of the secondary heater 5 via a pipeline, serving as hot steam for heating the material.

[0022] The secondary heater has a material inlet, a material outlet, a steam inlet, and a secondary steam outlet. The material outlet of the secondary heater 5 is connected to the material inlet of the secondary separator 6 via a pipeline. The device also includes a crystallizer 7. The material outlet of the secondary separator 6 is connected to the crystallizer 7 via a pipeline. The secondary separator 6 is connected to the material inlet of the secondary heater 5 via a secondary circulation pump 8 and a pipeline. The material in the secondary evaporator circulates at a high flow rate between the secondary heater 5, the secondary separator 6, and the crystallizer 7, driven by the secondary circulation pump 8. After being heated by the secondary heater, the material enters the secondary separator and boils, generating secondary steam. The material becomes a supersaturated solution and enters the bottom of the crystallizer. A large number of potassium fluoride crystals are suspended in the crystallization zone at the bottom of the crystallizer. As the supersaturated material passes through the crystallization zone from the bottom upwards, the supersaturation is gradually eliminated, promoting crystal growth. The clarified solution after the supersaturation is eliminated is re-entered into the heater by the secondary circulation pump for evaporation and concentration.

[0023] The secondary steam outlet of the secondary separator 6 is connected to the condenser 14 via a pipeline. The low-pressure secondary steam evaporated from the secondary separator 6 enters the condenser 14 for condensation. Furthermore, the gas outlet of the condenser 14 is typically connected to the vacuum pump 15 via a pipeline, and a small amount of non-condensable gas is drawn out of the system by the vacuum pump 15.

[0024] In the specific implementation, crystallizer 7 is an OSLO crystallizer. The material crystallizes within the crystallizer to form a crystal slurry. The crystal slurry outlet of crystallizer 7 is connected to the crystal slurry inlet of thickener 10 via discharge pump 9 and a pipeline. The discharge port of thickener 10 is connected to centrifuge 11 via a pipeline. The clear liquid outlet of thickener 10 is connected to mother liquor tank 12 via a pipeline; the clear liquid outlet of centrifuge 11 is also connected to mother liquor tank 12 via a pipeline. The crystal slurry from the crystallization zone in crystallizer 7 is pumped into thickener 10 via discharge pump 9. Within thickener 10, the supernatant of the crystal slurry overflows into mother liquor tank 12, and the thickened material at the bottom enters centrifuge 11 to separate potassium fluoride crystals and centrifugal mother liquor. The potassium fluoride crystals then enter the subsequent drying system.

[0025] The outlet of the mother liquor tank 12 is connected to the crystallizer 7 via the mother liquor pump 13 and a pipeline. The centrifuged mother liquor enters the mother liquor tank 12, and the mother liquor in the mother liquor tank 12 is pumped into the crystallizer 7 by the mother liquor pump 12 to continue to participate in evaporation and crystallization.

[0026] The device typically includes a condensate tank 16 for storing condensate. The condensate outlet of the condensing unit 14 is connected to the condensate tank 16 via a pipe; the condensate outlet of the secondary heater 5 is also connected to the condensate tank 16 via a pipe. A condensate pump 17 is connected to the condensate outlet of the condensate tank 16. The condensate from the secondary heater 5 and the condensing unit 14 enters the condensate tank 16 and is then discharged from the system by the condensate pump 17.

[0027] In practical implementation, the condensing device 14 is an evaporative condenser, and the gas outlet of the evaporative condenser is connected to the vacuum pump. Alternatively, a condenser plus a cooling tower can be used.

[0028] The pipes in this device, for materials, condensate, and steam, are all different pipes that meet the conveying requirements.

[0029] The following is the workflow: Following the material flow, low-concentration materials first enter the primary evaporator for evaporation and concentration. Within the primary evaporator, the material circulates at a high flow rate between the primary heater 1 and the primary separator 2, driven by the primary circulation pump 3. After being heated by the primary heater 1, the material enters the primary separator 2 and boils, generating secondary steam for further concentration. The concentrated material is then pumped by the transfer pump 4 into the secondary evaporator for continued evaporation and concentration.

[0030] The material in the secondary evaporator circulates at a high flow rate between the secondary heater 5, secondary separator 6, and crystallizer 7, driven by the secondary circulation pump 8. After being heated by the secondary heater 5, the material enters the secondary separator 6 and boils, generating secondary steam. The material becomes a supersaturated solution and enters the bottom of the crystallizer 7. A large number of potassium fluoride crystals are suspended in the crystallization zone at the bottom of the crystallizer 7. As the supersaturated material passes through the crystallization zone from the bottom upwards, the supersaturation is gradually eliminated, promoting crystal growth. The clarified solution after the supersaturation is eliminated re-enters the secondary heater 5 via the secondary circulation pump 8 for evaporation and concentration.

[0031] The crystal slurry in the crystallization zone of the crystallizer 7 is pumped into the thickener 10 by the discharge pump 9. The supernatant of the thickener 10 overflows into the mother liquor tank 12. The material after thickening at the bottom enters the centrifuge 11 to separate potassium fluoride crystals and centrifugal mother liquor. The potassium fluoride crystals enter the subsequent drying system, and the centrifugal mother liquor enters the mother liquor tank. The mother liquor in the mother liquor tank 12 is pumped into the crystallizer by the mother liquor pump 13 to continue to participate in evaporation and crystallization.

[0032] In this device, the number of evaporator stages in the main evaporation system is not limited and can be selected according to the evaporation capacity. Three-stage, four-stage, or even multiple evaporators can be set up to form a multi-stage evaporator, thus creating a multi-effect evaporation system. Each evaporator, as described above, mainly includes a heater and a separator; the multi-stage evaporator setup follows a two-stage evaporation configuration, with the multi-stage evaporator added later.

[0033] This utility model discloses a continuous potassium fluoride crystallization device. The main equipment adopts a multi-effect design, allowing for multiple uses of steam. Compared to spray drying towers where the heat source is used only once and then discharged from the system, this significantly reduces production energy consumption. The device uses an evaporative condenser, which further reduces system operating energy consumption compared to traditional condensers.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A continuous potassium fluoride crystallization apparatus, characterized in that: It includes a primary evaporator and a secondary evaporator; the primary evaporator includes a primary heater (1) and a primary separator (2); the material inlet of the primary separator (2) is connected to the material outlet of the primary heater (1); the material outlet of the primary separator (2) is connected to the material inlet of the primary heater (1) through a primary circulating pump (3); the primary heater (1) is provided with a steam inlet and a condensate outlet; The secondary evaporator includes a secondary heater (5) and a secondary separator (6); the material outlet of the primary separator (2) is also connected to the material inlet of the secondary heater (5) via a transfer pump (4); the steam outlet of the primary separator (2) is connected to the steam inlet of the secondary heater (5); the material outlet of the secondary heater (5) is connected to the material inlet of the secondary separator (6); The material outlet of the secondary separator (6) is connected to the crystallizer (7); the secondary steam outlet of the secondary separator (6) is connected to the condenser; the secondary separator (6) is connected to the material inlet of the secondary heater (5) through the secondary circulation pump (8).

2. The potassium fluoride continuous crystallization apparatus according to claim 1, characterized in that: The crystal slurry outlet of the crystallizer (7) is connected to the crystal slurry inlet of the thickener (10) via the discharge pump (9); the discharge port of the thickener (10) is connected to the centrifuge (11); the clear liquid outlet of the thickener (10) is connected to the mother liquor tank (12); and the clear liquid outlet of the centrifuge (11) is connected to the mother liquor tank (12).

3. The potassium fluoride continuous crystallization apparatus according to claim 2, characterized in that: The outlet of the mother liquor tank (12) is connected to the crystallizer (7) via the mother liquor pump (13).

4. The potassium fluoride continuous crystallization apparatus according to claim 1, characterized in that: The condensate outlet of the condensing device (14) is connected to the condensate tank (16); the condensate outlet of the secondary heater (5) is connected to the condensate tank (16); and the condensate outlet of the condensate tank (16) is connected to a condensate pump (17).

5. A potassium fluoride continuous crystallization apparatus according to any one of claims 1-4, characterized in that: The condensing equipment (14) is an evaporative condenser, and the gas outlet of the evaporative condenser is connected to the vacuum pump (15); or the condensing equipment (14) adopts the form of a condenser plus a cooling tower.

6. A potassium fluoride continuous crystallization apparatus according to any one of claims 1-4, characterized in that: The crystallizer (7) is an OSLO crystallizer.

7. A potassium fluoride continuous crystallization apparatus according to any one of claims 1-4, characterized in that: It also includes multi-stage evaporators designed according to the amount of evaporation.

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