An evaporation salt resource recovery device

Abstract

This utility model discloses an evaporative salt separation and resource recovery device, belonging to the field of industrial high-salt wastewater treatment technology. It includes a pretreatment unit, an MVR evaporation unit, an ultrasonic crystallization unit, and a centrifugal separation unit. The ultrasonic crystallization unit includes a cryogenic crystallizer and a three-stage countercurrent evaporator. The cryogenic crystallizer is connected to the evaporative crystallizer via a pipeline, and the three-stage countercurrent evaporator is connected to a flash cooling device via a pipeline. The ultrasonic generator is connected to the cryogenic crystallizer, the evaporative crystallizer, the three-stage countercurrent evaporator, and the flash cooling device via pipelines. This evaporative salt separation and resource recovery device, by connecting the ultrasonic generator to the cryogenic crystallizer, the evaporative crystallizer, the three-stage countercurrent evaporator, and the flash cooling device, allows the ultrasonic generator to effectively suppress scaling and intergranular inclusions on the crystallizer wall using the ultrasonic cavitation effect, improving heat exchange efficiency and product purity, thereby effectively preventing scaling on the vessel wall and improving crystal purity and particle size uniformity.

Description

Technical Field

[0001] This utility model belongs to the field of industrial high-salt wastewater treatment technology, specifically, it relates to an evaporation and salt separation resource recovery device. Background Technology

[0002] With rapid industrialization, the discharge of high-salinity wastewater is increasing, especially in fields such as waste incineration fly ash treatment, coal chemical industry, metallurgy, and pharmaceuticals, which generate large amounts of wastewater with complex composition and high salt concentration. Direct discharge of this type of wastewater would cause serious pollution to water bodies, soil, and the ecological environment, while also wasting the large amount of salt resources it contains. Existing technologies mostly employ thermal salt separation, membrane salt separation, MVR evaporation crystallization salt separation systems, and three-stage countercurrent evaporation salt separation systems. However, the quality of the crystallized salt is slightly lower, and the purity of the final product salt is significantly affected by fluctuations in the composition of the incoming material. In particular, when the wastewater contains multiple salts or organic matter, it is easy to cause eutectic phenomena, resulting in substandard product purity and difficulty in resource utilization. Furthermore, high-concentration and high-viscosity materials are prone to scaling and clogging, thereby reducing crystallization purity and particle size uniformity. To address the aforementioned problems, this application proposes an evaporation and salt separation resource recovery device. Utility Model Content

[0003] In view of the problems in the related technologies, this utility model proposes an evaporation and salt resource recovery device to overcome the above-mentioned technical problems existing in the existing related technologies.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: An evaporative salt resource recovery device includes a pretreatment unit, an MVR evaporation unit, an ultrasonic crystallization unit, and a centrifugal separation unit. The ultrasonic crystallization unit includes a cryogenic crystallizer and a three-stage countercurrent evaporator. The cryogenic crystallizer is connected to an evaporative crystallizer via a pipeline. The three-stage countercurrent evaporator is connected to a flash cooling device via a pipeline. The cryogenic crystallizer, evaporative crystallizer, three-stage countercurrent evaporator, and flash cooling device are all connected to an ultrasonic generator via pipelines.

[0005] Preferably, the ultrasonic crystallization unit is equipped with a water quality analyzer, a temperature sensor, and a pressure sensor.

[0006] Preferably, the pretreatment unit includes a regulating tank, a high-precision filter, and a softening reactor connected in sequence by pipelines, and the outer wall of the softening reactor is provided with a dosing assembly.

[0007] Preferably, the MVR evaporation unit includes a steam compressor, which is connected to the softening reactor via a pipeline. An MVR evaporator is located on the side of the steam compressor away from the softening reactor, and the steam compressor is connected to the MVR evaporator via a pipeline.

[0008] Preferably, the centrifugal separation unit includes a thickener, which is connected to a centrifuge via a pipe, and the side of the centrifuge away from the thickener is connected to a fluidized bed dryer via a pipe.

[0009] In summary, the technical effects and advantages of this utility model are as follows: This evaporative salt resource recovery device connects an ultrasonic generator to a freezing crystallizer, an evaporative crystallizer, a three-stage countercurrent evaporator, and a flash cooling device. The ultrasonic generator utilizes the ultrasonic cavitation effect to effectively suppress scaling on the crystallizer wall and intercrystalline inclusions, thereby improving heat exchange efficiency and product purity. This effectively prevents scaling on the vessel wall and further improves crystal purity and particle size uniformity. Attached Figure Description

[0010] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a flowchart of the present invention.

[0011] In the diagram: 1. Pretreatment unit; 101. Adjustment tank; 102. High-precision filter; 103. Softening reactor; 104. Dosing assembly; 2. MVR evaporation unit; 201. Steam compressor; 202. MVR evaporator; 3. Ultrasonic crystallization unit; 301. Freezing crystallizer; 302. Evaporation crystallizer; 303. Three-stage countercurrent evaporator; 304. Flash cooling device; 305. Ultrasonic generator; 4. Centrifugal separation unit; 401. Thickener; 402. Centrifuge; 403. Fluidized bed dryer. Detailed Implementation

[0012] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0013] Reference Figure 1-2An evaporative salt recovery device includes a pretreatment unit 1, an MVR evaporation unit 2, an ultrasonic crystallization unit 3, and a centrifugal separation unit 4. The ultrasonic crystallization unit 3 includes a cryogenic crystallizer 301 and a three-stage countercurrent evaporator 303. The cryogenic crystallizer 301 is connected to an evaporative crystallizer 302 via a pipe. The three-stage countercurrent evaporator 303 is connected to a flash cooling device 304 via a pipe. The cryogenic crystallizer 301, evaporative crystallizer 302, three-stage countercurrent evaporator 303, and flash cooling device 304 are all connected to an ultrasonic generator 305 via pipes. After treatment by the pretreatment unit 1 and the MVR evaporation unit 2, high-salt wastewater or fly ash leachate forms a saturated solution. The concentrated saturated solution... Depending on the salt composition, different crystallization paths are used. For the NaCl-Na2SO4 system, sodium sulfate decahydrate is precipitated first in the freeze crystallizer 301, and then sodium chloride is precipitated in the evaporator crystallizer 302. For the NaCl-KCl system, sodium chloride is precipitated in the three-stage countercurrent evaporator 303, and then potassium chloride is precipitated in the flash cooling device 304. When the freeze crystallizer 301, evaporator crystallizer 302, three-stage countercurrent evaporator 303 and flash cooling device 304 are in operation, the ultrasonic waves generated by the ultrasonic generator 305 are transmitted to the crystallization zone through the transducer and amplitude transformer. The ultrasonic cavitation effect effectively destroys the crystal nucleus aggregation, prevents scaling on the device wall, and improves the crystal purity and particle size uniformity.

[0014] Reference Figure 1-2 The ultrasonic crystallization unit 3 is equipped with a water quality analyzer, a temperature sensor, and a pressure sensor. These sensors monitor the concentrated saturated solution and can detect the Cl content in the solution. - SO4 2- K + Concentration, temperature, and pressure sensors adjust the evaporation temperature, compressor frequency, and ultrasonic parameters in real time to achieve optimal salt separation.

[0015] Reference Figure 1-2 The pretreatment unit 1 includes a regulating tank 101, a high-precision filter 102, and a softening reactor 103 connected in sequence by pipelines. A dosing assembly 104 is provided on the outer wall of the softening reactor 103. The high-salt wastewater or fly ash leachate is pretreated by the regulating tank 101, the high-precision filter 102, and the softening reactor 103. The water quality and quantity of the high-salt wastewater or fly ash leachate are balanced by the regulating tank 101. Then, suspended solids and colloidal substances are removed by the high-precision filter 102. Finally, calcium and magnesium ions and silicates in the solution are removed by the softening reactor 103 and the dosing assembly 104.

[0016] Reference Figure 1-2The MVR evaporation unit 2 includes a steam compressor 201, which is connected to the softening reactor 103 via a pipe. An MVR evaporator 202 is installed on the side of the steam compressor 201 away from the softening reactor 103. The steam compressor 201 and the MVR evaporator 202 are connected via a pipe. The pretreated wastewater enters the interior of the MVR evaporation unit 2. The secondary steam is compressed and heated by the steam compressor 201 and then recycled as a heat source. The wastewater is heated to boiling in the MVR evaporator 202 and gradually concentrated to near saturation.

[0017] Reference Figure 1-2 The centrifugal separation unit 4 includes a thickener 401, which is connected to a centrifuge 402 via a pipe. The side of the centrifuge 402 away from the thickener 401 is connected to a fluidized bed dryer 403 via a pipe. After the concentrated saturated solution is crystallized by the ultrasonic crystallization unit 3, the crystallized slurry enters the thickener 401 for preliminary concentration. After concentration, it enters the centrifuge 402 for solid-liquid separation. The separated wet crystals enter the fluidized bed dryer 403 for drying, thereby obtaining a high-purity crystalline salt product.

[0018] Working principle: High-salt wastewater or fly ash leachate is treated through pretreatment unit 1, MVR evaporation unit 2, ultrasonic crystallization unit 3, and centrifugal separation unit 4. The high-salt wastewater or fly ash leachate undergoes preliminary treatment through regulating tank 101, high-precision filter 102, and softening reactor 103 to remove suspended solids, colloidal substances, calcium and magnesium ions, and silicates. The pretreated wastewater is then heated and concentrated through steam compressor 201 and MVR evaporator 202 to form a concentrated saturated solution. The saturated solution is analyzed by a water quality analyzer, temperature sensor, and pressure sensor to distinguish the system composition. For the NaCl-Na2SO4 system, it first enters the freeze crystallizer. Sodium sulfate decahydrate precipitates in evaporator 301, and then sodium chloride precipitates in evaporator crystallizer 302. For the NaCl-KCl system, sodium chloride is precipitated by evaporation in three-stage countercurrent evaporator 303, and then potassium chloride precipitates by flash cooling device 304. During the crystallization process, ultrasonic waves generated by ultrasonic generator 305 are transmitted to the crystallization zone through transducer and amplitude transformer. The ultrasonic cavitation effect effectively destroys the crystal nucleus aggregation, prevents scaling on the vessel wall, and improves the crystal purity and particle size uniformity. The final crystallized slurry enters the thickener 401 for preliminary concentration, and then enters the centrifuge 402 for solid-liquid separation. The separated wet crystals enter the fluidized bed dryer 403 for drying, thereby obtaining a high-purity crystalline salt product.

[0019] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An evaporation and salt resource recovery device, comprising a pretreatment unit (1), an MVR evaporation unit (2), an ultrasonic crystallization unit (3), and a centrifugal separation unit (4), characterized in that, The ultrasonic crystallization unit (3) includes a cryogenic crystallizer (301) and a three-stage countercurrent evaporator (303). The cryogenic crystallizer (301) is connected to an evaporative crystallizer (302) via a pipe. The three-stage countercurrent evaporator (303) is connected to a flash cooling device (304) via a pipe. The cryogenic crystallizer (301), the evaporative crystallizer (302), the three-stage countercurrent evaporator (303), and the flash cooling device (304) are all connected to an ultrasonic generator (305) via pipes.

2. The evaporation and salt resource recovery device according to claim 1, characterized in that, The ultrasonic crystallization unit (3) is equipped with a water quality detector, a temperature sensor and a pressure sensor.

3. The evaporation and salt resource recovery device according to claim 1, characterized in that, The pretreatment unit (1) includes a regulating tank (101), a high-precision filter (102) and a softening reactor (103) connected in sequence by pipelines. The outer wall of the softening reactor (103) is provided with a dosing assembly (104).

4. The evaporation and salt resource recovery device according to claim 1, characterized in that, The MVR evaporation unit (2) includes a steam compressor (201), which is connected to the softening reactor (103) via a pipe. An MVR evaporator (202) is provided on the side of the steam compressor (201) away from the softening reactor (103), and the steam compressor (201) and the MVR evaporator (202) are connected via a pipe.

5. The evaporation and salt resource recovery device according to claim 1, characterized in that, The centrifugal separation unit (4) includes a thickener (401), which is connected to a centrifuge (402) via a pipe. The side of the centrifuge (402) away from the thickener (401) is connected to a fluidized bed dryer (403) via a pipe.

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