Salt-separating resourceful treatment system for high-salinity wastewater

Abstract

The utility model relates to a salt-separating resourceful treatment system for high-salt wastewater. The system comprises a nanofiltration (NF) device, an MVR sodium sulfate falling film concentration device, a freezing crystallization device, a mirabilite recrystallization device, a freezing mother liquor purification device, a freezing mother liquor NF device, an HPRO (High Pressure Reverse Osmosis) device, a nanofiltration (NF) produced water purification device, an MVR sodium chloride falling film concentration device, an MVR sodium chloride crystallization device, a potassium chloride cooling crystallization device and a mother liquor drying device. The method is suitable for a high-salinity wastewater salt separation recycling scene, can realize separation of sodium chloride, sodium sulfate and potassium chloride crystal salt in wastewater, and reduces the wastewater treatment cost.

Description

Technical Field

[0001] This utility model belongs to the field of high-salt wastewater salinization resource utilization, and particularly relates to a high-salt wastewater salinization resource utilization treatment system. Background Technology

[0002] Traditional evaporation crystallization processes for treating high-salinity wastewater from evaporation ponds generate large amounts of waste salt. Depending on the source of the wastewater, this waste salt may be classified as general solid waste or hazardous waste, making treatment both difficult and costly. Adopting a high-salinity wastewater desalination and resource recovery process can reduce waste salt generation and lower wastewater treatment costs. Summary of the Invention

[0003] The purpose of this invention is to provide a high-salt wastewater desalination resource utilization system, which can separate sodium chloride, potassium chloride and sodium sulfate crystals in high-salt wastewater and reduce the impurity salt rate in the wastewater treatment process.

[0004] To solve the above-mentioned technical problems, the specific technical solution of this utility model is as follows:

[0005] A high-salt wastewater desalination resource utilization system includes a nanofiltration (NF) unit, an MVR sodium sulfate falling film concentration unit, a freeze crystallization unit, a Glauber's salt recrystallization unit, a freeze mother liquor purification unit, a freeze mother liquor NF unit, an HPRO high-pressure reverse osmosis unit, a nanofiltration (NF) permeate purification unit, an MVR sodium chloride falling film concentration unit, an MVR sodium chloride crystallization unit, a potassium chloride cooling crystallization unit, and a mother liquor drying unit.

[0006] The nanofiltration (NF) device is used for the initial separation of monovalent and divalent salts. The product water outlet of the nanofiltration (NF) device is connected to the HPRO high-pressure reverse osmosis device, and the concentrate outlet of the nanofiltration (NF) device is connected to the MVR sodium sulfate falling membrane concentration device.

[0007] The MVR sodium sulfate falling film concentration unit is used for further concentration of the concentrate from the nanofiltration (NF) unit, and the concentrate outlet of the MVR sodium sulfate falling film concentration unit is connected to the freeze crystallization unit.

[0008] The freezing crystallization device is used for sodium sulfate separation. The salt outlet of the freezing crystallization device is connected to the sodium sulfate recrystallization device, and the water outlet of the freezing crystallization device is connected to the freezing mother liquor purification device.

[0009] The frozen mother liquor purification device is used for decolorizing and removing COD from the frozen mother liquor, and the outlet of the frozen mother liquor purification device is connected to the frozen mother liquor NF device.

[0010] The frozen mother liquor NF device is used for the recovery of monovalent salts from frozen mother liquor. The product water outlet of the frozen mother liquor NF device is connected to the RO concentrate tank, the RO concentrate tank is connected to the nanofiltration NF product water purification device, and the concentrate outlet of the frozen mother liquor NF device is connected to the mother liquor drying device.

[0011] The HPRO high-pressure reverse osmosis unit is used to further concentrate the permeate from the nanofiltration NF unit, and the concentrate outlet of the HPRO high-pressure reverse osmosis unit is connected to the nanofiltration NF permeate purification unit.

[0012] The nanofiltration NF permeate purification device is used to remove hardness, fluoride ions, and silica impurities from nanofiltration NF permeate and frozen mother liquor NF permeate. The outlet of the nanofiltration NF permeate purification device is connected to the MVR sodium chloride falling film concentration device.

[0013] The MVR sodium chloride falling film concentration unit is used for further concentration of the effluent from the nanofiltration NF permeate purification unit, and the concentrate outlet of the MVR sodium chloride falling film concentration unit is connected to the MVR sodium chloride evaporation and crystallization unit.

[0014] The MVR sodium chloride crystallization device is used for sodium chloride crystallization and separation, and the concentrate outlet of the MVR sodium chloride crystallization device is connected to the potassium chloride cooling crystallization device.

[0015] The potassium chloride cooling crystallization device is used for potassium chloride crystallization and separation, and the concentrated water outlet of the potassium chloride cooling crystallization device is also connected to the mother liquor drying device.

[0016] Furthermore, the frozen mother liquor purification device and the frozen mother liquor NF device decolorize the mother liquor and remove organic matter by adding a strong oxidant, and recover monovalent salts from the frozen mother liquor by the frozen mother liquor NF device, thereby reducing the scale of mother liquor drying treatment and the amount of impurities.

[0017] Furthermore, the MVR sodium chloride crystallization unit and potassium chloride cooling crystallization unit are equipped with an improved OSLO-type crystallizer. By increasing the size of the central circulation pipe in the OSLO crystallizer and adding salt legs, the grading, washing, and crystallization of sodium chloride crystallized salt are achieved, while reducing the residual impurities in the crystallized output. By using the improved OSLO-type crystallizer, the downward flow velocity in the central circulation pipe is reduced to below 0.5 m / s through increasing the size of the central circulation pipe, and the addition of salt legs further improves the quality of the crystallized salt.

[0018] Furthermore, the potassium chloride cooling crystallization device is equipped with a multi-stage continuous cooling crystallization unit to obtain potassium chloride crystals, achieving automated operation and simultaneously obtaining potassium chloride crystals with good particle size.

[0019] Furthermore, the potassium chloride cooling crystallization device includes a potassium chloride flash evaporator, a potassium chloride crystallizer, a potassium chloride slurry tank, a potassium chloride thickener, a potassium chloride centrifuge, and a potassium chloride mother liquor tank.

[0020] The potassium chloride flash chamber is used for primary cooling of potassium chloride, and its outlet is connected to the potassium chloride crystallizer.

[0021] The potassium chloride crystallizer is used for secondary cooling and primary crystallization of potassium chloride, and its outlet is connected to the potassium chloride crystal slurry tank.

[0022] The potassium chloride crystal slurry tank is used to eliminate the boiling point rise of potassium chloride, and its outlet is connected to the potassium chloride thickener.

[0023] The potassium chloride thickener is used to increase the solid-liquid ratio of the potassium chloride output. Its outlet is connected to the potassium chloride centrifuge, and the supernatant overflow is connected to the potassium chloride mother liquor tank.

[0024] The potassium chloride centrifuge is used for solid-liquid separation of potassium chloride crystallized salt. The crystallized salt enters the crystallized salt packaging machine, and the centrifugal mother liquor is connected to the potassium chloride mother liquor tank.

[0025] The potassium chloride mother liquor tank is used to collect potassium chloride thickener and centrifuged mother liquor, and its outlet is connected to the MVR sodium chloride evaporation and crystallization device and the mother liquor drying device.

[0026] This utility model provides a high-salt wastewater desalination resource utilization system, which has the following advantages:

[0027] 1. This utility model further reduces calcium and magnesium hardness, fluoride, COD and other impurities in the evaporation crystallization feed and operation process by setting up a nanofiltration (NF) permeate purification device and a freezing mother liquor purification device, thereby reducing the enrichment of impurities and color, avoiding frequent scaling during equipment operation, improving the quality of crystallized salts and reducing the impurity rate.

[0028] 2. The nanofiltration (NF) device of this utility model is equipped with two-stage salt separation, that is, the nanofiltration (NF) permeate enters the secondary nanofiltration (NF) device, the permeate of the secondary nanofiltration (NF) device is connected to the HPRO (high pressure reverse osmosis) device, and the concentration of the secondary nanofiltration (NF) device is connected to the inlet of the nanofiltration (NF) device.

[0029] 3. This utility model is equipped with a potassium chloride crystallization device, which adds the separation of potassium chloride on the basis of traditional salt-nitrate separation, realizes the resource utilization of potassium chloride crystallized salt, and improves the economic efficiency of operation.

[0030] 4. The potassium chloride cooling crystallization device is equipped with multi-stage continuous cooling crystallization of potassium chloride, which can realize automated operation and obtain potassium salt with good particle size. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a high-salt wastewater desalination resource utilization process proposed in the utility model.

[0032] Figure 2 This is a schematic diagram of the potassium chloride desalting and resource utilization process proposed in the utility model.

[0033] Figure 3 This is a schematic diagram of the OSLO-type improved crystallizer structure proposed in the utility model. Detailed Implementation

[0034] To better understand the purpose, structure, and function of this utility model, the following description, in conjunction with the accompanying drawings, provides a more detailed account of a high-salt wastewater salinization resource recovery system.

[0035] The technical solution for realizing the resource utilization of high-salt wastewater salinity in this utility model is as follows: A high-salt wastewater salinity resource utilization process system includes a nanofiltration (NF) device, an MVR sodium sulfate falling film concentration device, a freeze crystallization device, a Glauber's salt recrystallization device, a freeze mother liquor purification device, a freeze mother liquor NF device, an HPRO (high pressure reverse osmosis) device, a nanofiltration (NF) permeate purification device, an MVR sodium chloride falling film concentration device, an MVR sodium chloride crystallization device, a potassium chloride cooling crystallization device, and a mother liquor drying device;

[0036] The nanofiltration (NF) device utilizes the sieving effect of nanofiltration membrane pore size to separate monovalent and divalent salts in high-salt wastewater. The product outlet of the nanofiltration (NF) device is connected to the HPRO (high-pressure reverse osmosis) device, and the concentrate outlet of the nanofiltration (NF) device is connected to the MVR sodium sulfate falling membrane concentration device.

[0037] The MVR sodium sulfate falling film concentration unit is used for further evaporation, volume reduction, and concentration of the concentrate from the nanofiltration (NF) unit. The concentrate outlet of the MVR sodium sulfate falling film concentration unit is connected to the freeze crystallization unit.

[0038] The cryo-crystallization device achieves crystallization separation of the MVR sodium sulfate falling film concentrate mother liquor by cooling, and obtains sodium sulfate (sodium sulfate decahydrate) crystal salt. The salt outlet of the cryo-crystallization device is connected to the sodium sulfate recrystallization device, and the mother liquor outlet of the cryo-crystallization device is connected to the cryo-mother liquor purification device.

[0039] The Glauber's salt recrystallization unit is used to obtain industrial-grade anhydrous sodium sulfate from Glauber's salt (sodium sulfate decahydrate) crystallization salt through redissolution, evaporation and crystallization; its inlet is connected to the salt outlet of the freeze crystallization, and its outlet is connected to the drying and packaging of sodium sulfate crystallization salt.

[0040] The frozen mother liquor purification device is used to remove impurities from the frozen mother liquor. It removes color and organic matter from the wastewater by setting up a strong oxidant dosing device. The outlet of the frozen mother liquor purification device is connected to the frozen mother liquor NF device.

[0041] The frozen mother liquor NF is further recovered to recover monovalent salts from the mother liquor. The concentrated frozen mother liquor NF enters the RO concentration tank and is connected to the mother liquor drying device through a pipeline.

[0042] Nanofiltration (NF) permeate enters HPRO for concentration and volume reduction. The HPRO concentrate is mixed with the frozen mother liquor NF permeate and then enters the nanofiltration (NF) permeate purification unit.

[0043] The nanofiltration (NF) permeate purification device is used to remove impurities such as calcium, magnesium, fluoride ions, and silicon from the incoming water, and its effluent is connected to the MVR sodium chloride falling film concentration device.

[0044] The MVR sodium chloride falling film concentration evaporates and concentrates the incoming water, and is connected to the MVR sodium chloride crystallization device through a pipeline for primary salt separation of nanofiltration (NF) permeate to obtain industrial-grade sodium chloride crystals. The concentration outlet of the MVR sodium chloride crystallization device is connected to the potassium chloride cooling crystallization device.

[0045] The potassium chloride cooling crystallization process cools the mother liquor after primary salt separation, achieving secondary salt separation to obtain industrial-grade potassium chloride. The mother liquor outlet is connected to the MVR sodium chloride crystallization device and the mother liquor drying device.

[0046] Most of the mother liquor after salt separation is recycled to the MVR sodium chloride crystallization unit, and the rest is dried through pipeline connection to achieve zero water discharge in the system. The crystallized salt is disposed of as waste salt.

[0047] like Figure 1 As shown, the nanofiltration (NF) unit is mainly used for the separation of monovalent and divalent salts from high-salinity wastewater. After pretreatment, the high-salinity wastewater enters the salt separation system. The raw water first enters the nanofiltration (NF) system, where monovalent and divalent ions are separated by the nanofiltration membrane, resulting in increased concentration and a higher nitrate ratio on the NF concentrate side. The NF permeate side yields highly pure monovalent salts, which are further concentrated and reduced in volume using an HPRO (High-Performance Bioreactor) system. The concentrate then enters the RO (Reverse Oxidation) concentrate tank. The nanofiltration (NF) and HPRO systems are connected via a nanofiltration permeate tank and an HPRO inlet pump. The nanofiltration (NF) and MVR (Medium-Vacuum Ripple) sodium sulfate falling membrane concentrate are connected via the nanofiltration (NF) concentrate tank and an MVR sodium sulfate falling membrane concentrate inlet pump.

[0048] The MVR sodium sulfate falling film evaporator is mainly used for further concentration and volume reduction of materials from nanofiltration (NF) concentrate. The sodium sulfate output concentration can be controlled at 20-26%. The raw material is fed into the raw water preheater via the MVR sodium sulfate feed pump. After preheating, the material enters the MVR sodium sulfate falling film evaporator to participate in the material distribution and circulation. The concentrated material is then pumped back to the preheater for cooling before being sent to the freeze crystallization unit.

[0049] Freeze-crystallization apparatus: Primarily used for the crystallization and separation of sodium sulfate (decahydrate). Utilizing the temperature-dependent solubility characteristics of sodium sulfate and sodium chloride, the apparatus controls the operating temperature (-5~0℃) to achieve the crystallization of sodium sulfate decahydrate from the material. Because the crystallized salt obtained through freeze-crystallization has high purity, it effectively removes the influence of organic matter and impurities on the quality of the crystallized salt. This invention obtains high-quality sodium sulfate crystallized salt through a process of first freeze-crystallization followed by recrystallization of sodium sulfate. The sodium sulfate crystallized salt meets the Class II Grade 1 requirements of GB / T6009-2014.

[0050] Glauber's salt recrystallization device: mainly used to convert Glauber's salt into anhydrous sodium sulfate crystals. This invention adopts a Glauber's salt re-dissolution + MVR evaporation crystallization + drying process. The evaporation crystallizer adopts an FC + salt leg type, which can obtain sodium sulfate crystals with high particle size and purity. After solid-liquid separation, it enters the drying equipment to obtain industrial-grade sodium sulfate crystals.

[0051] Cryogenic Mother Liquor Purification Unit: Primarily used for removing organic matter from cryogenic mother liquor. Nanofiltration (NF) has a certain retention capacity for organic matter, and a certain amount of organic matter, especially chromogenic substances, will accumulate in the cryogenic mother liquor. By setting up a cryogenic mother liquor purification unit, strong oxidants are added to oxidize the chromogenic organic matter in the wastewater, reducing the amount of organic matter in the subsequent cryogenic mother liquor NF feed, reducing NF fouling, and simultaneously ensuring the color of the cryogenic mother liquor NF product.

[0052] The NF unit for cryogenic mother liquor is mainly used to recover monovalent salts from cryogenic mother liquor, reducing the salt content of discharged mother liquor. Cryogenic mother liquor is primarily composed of sodium chloride and potassium chloride; direct discharge would increase the processing capacity and cost of the mother liquor drying unit, while also generating a large amount of waste salt.

[0053] HPRO (High Pressure Reverse Osmosis) unit: mainly used for concentration and volume reduction of nanofiltration (NF) permeate.

[0054] Nanofiltration (NF) permeate purification unit: mainly used for further impurity removal from the feed water of MVR sodium chloride falling film concentration. By adding reagents, residual impurities such as hardness, silica, fluoride ions, and COD in the wastewater are removed, thereby increasing the subsequent evaporation, crystallization, and concentration ratio, improving the quality of the crystallized salt, and reducing the amount of mother liquor discharged.

[0055] The MVR sodium chloride falling film evaporator is mainly used for further concentration and volume reduction of HPRO concentrate. The raw material is fed into the raw water preheater via the MVR sodium chloride feed pump. After preheating, the material enters the MVR sodium chloride falling film evaporator to participate in the material distribution and circulation. The concentrated material is then pumped into the MVR evaporation and crystallization unit, where the sodium chloride concentrate concentration can reach 20-25%.

[0056] MVR sodium chloride crystallization unit: Primarily used for separating sodium chloride crystals. This invention targets wastewater with high potassium chloride content, where nanofiltration (NF) permeate is mainly sodium chloride with a certain amount of potassium chloride. To reduce the amount of impurities in the system, a sodium-potassium salt separation system is implemented. The MVR sodium chloride crystallization mother liquor enters the subsequent potassium chloride cooling crystallization system to produce potassium chloride. To ensure the purity of the potassium chloride crystals, the solid content of the sodium chloride output must be minimized. Therefore, an improved OSLO crystallizer is selected as the MVR sodium chloride crystallizer, which can effectively achieve solid-liquid separation of materials within the crystallizer. The endpoint for discharging the MVR sodium chloride evaporation crystallization mother liquor is to control the potassium chloride mass concentration at 18-21%.

[0057] Potassium chloride cooling crystallization device: mainly used for separating potassium chloride crystal salts.

[0058] Mother liquor drying device: mainly used to treat the mother liquor from evaporation and crystallization, achieve zero discharge of system water, and obtain a small amount of waste salt.

[0059] The specific components of the potassium chloride cooling crystallization device are as follows: Figure 2 As shown, it includes a potassium chloride flash evaporator, a potassium chloride crystallizer, a potassium chloride slurry tank, a potassium chloride thickener, a potassium chloride centrifuge, and a potassium chloride mother liquor tank.

[0060] Taking advantage of the characteristic that the solubility of potassium chloride decreases with decreasing temperature, a three-stage continuous cooling and crystallization unit consisting of a potassium chloride flash evaporator, a potassium chloride crystallizer, and a potassium chloride crystal slurry tank is set up to obtain potassium chloride crystalline salt. The cooling and crystallization temperature is controlled at 30~50℃ according to the cooling medium, which is more economical and reasonable.

[0061] The potassium chloride flash chamber is used for primary cooling of potassium chloride, and its outlet is connected to the potassium chloride crystallizer.

[0062] The potassium chloride crystallizer is used for secondary cooling and primary crystallization of potassium chloride, and its outlet is connected to the potassium chloride crystal slurry tank.

[0063] The potassium chloride crystal slurry tank is used to eliminate the boiling point rise of potassium chloride and cool the potassium chloride to the design level, while the potassium chloride crystal salt can grow more fully. Its outlet is connected to the potassium chloride thickener.

[0064] The potassium chloride thickener is used to increase the solid-liquid ratio of the potassium chloride output. Its outlet is connected to the potassium chloride centrifuge, and the supernatant overflow is connected to the potassium chloride mother liquor tank.

[0065] The potassium chloride centrifuge is used for solid-liquid separation of potassium chloride crystallized salt. The crystallized salt enters the crystallized salt packaging machine, and the centrifugal mother liquor is connected to the potassium chloride mother liquor tank.

[0066] The potassium chloride mother liquor tank is used to collect the thickener and centrifuged mother liquor, and its outlet is connected to the MVR sodium chloride evaporation and crystallization device and the mother liquor drying device.

[0067] This invention proposes a high-salinity wastewater desalination resource utilization system specifically for high-salinity wastewater, particularly high-potassium wastewater. The system incorporates a nanofiltration (NF) unit, which effectively adapts to the impact of influent water quality fluctuations on system operation and the quality of crystallized salts. Multiple purification units are used to remove impurities from the wastewater in stages, improving system reliability. Potassium salt separation employs a multi-stage continuous flash evaporation cooling crystallization + circulating water cooling method, enabling automatic and continuous potassium salt production. This is more convenient than traditional intermittent batch operation. The potassium salt crystallizer adopts an improved OSLO structure, which better facilitates potassium salt grading, washing, and crystallization while reducing crystal residue in the potassium salt mother liquor reflux.

[0068] Figure 3 This invention presents an improved OSLO crystallizer. The structure, from top to bottom, includes a secondary steam outlet, a vapor phase space, a clear liquid outlet, a central circulation pipe, circulating liquid inlet and outlet, salt legs, and a salt outlet. Based on the traditional OSLO crystallizer, the size of the central circulation pipe is increased, controlling the material flow velocity within the central circulation pipe to below 0.5 m / s. Furthermore, the bottom of the traditional OSLO crystallizer head is replaced with a salt leg structure. By incorporating the salt leg, the grading, washing, and crystallization of the crystallized salt are further optimized, while simultaneously reducing the residual impurities in the crystallized output.

[0069] It is understood that this utility model has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this utility model. Furthermore, under the teachings of this utility model, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this utility model.

Claims

1. A high-salinity wastewater desalination resource utilization system, characterized in that, Including nanofiltration (NF) units, MVR sodium sulfate falling membrane concentration units, freeze crystallization units, Glauber's salt recrystallization units, freeze mother liquor purification units, freeze mother liquor NF units, HPRO high-pressure reverse osmosis units, nanofiltration (NF) permeate purification units, MVR sodium chloride falling membrane concentration units, MVR sodium chloride crystallization units, potassium chloride cooling crystallization units, and mother liquor drying units; The nanofiltration (NF) device is used for the initial separation of monovalent and divalent salts. The product water outlet of the nanofiltration (NF) device is connected to the HPRO high-pressure reverse osmosis device, and the concentrate outlet of the nanofiltration (NF) device is connected to the MVR sodium sulfate falling membrane concentration device. The MVR sodium sulfate falling film concentration unit is used for further concentration of the concentrate from the nanofiltration (NF) unit, and the concentrate outlet of the MVR sodium sulfate falling film concentration unit is connected to the freeze crystallization unit. The freezing crystallization device is used for sodium sulfate separation. The salt outlet of the freezing crystallization device is connected to the sodium sulfate recrystallization device, and the water outlet of the freezing crystallization device is connected to the freezing mother liquor purification device. The frozen mother liquor purification device is used for decolorizing and removing COD from the frozen mother liquor, and the outlet of the frozen mother liquor purification device is connected to the frozen mother liquor NF device. The frozen mother liquor NF device is used for the recovery of monovalent salts from frozen mother liquor. The product water outlet of the frozen mother liquor NF device is connected to the RO concentrate tank, the RO concentrate tank is connected to the nanofiltration NF product water purification device, and the concentrate outlet of the frozen mother liquor NF device is connected to the mother liquor drying device. The HPRO high-pressure reverse osmosis unit is used to further concentrate the permeate from the nanofiltration NF unit, and the concentrate outlet of the HPRO high-pressure reverse osmosis unit is connected to the nanofiltration NF permeate purification unit. The nanofiltration NF permeate purification device is used to remove hardness, fluoride ions, and silica impurities from nanofiltration NF permeate and frozen mother liquor NF permeate. The outlet of the nanofiltration NF permeate purification device is connected to the MVR sodium chloride falling film concentration device. The MVR sodium chloride falling film concentration unit is used for further concentration of the effluent from the nanofiltration NF permeate purification unit, and the concentrate outlet of the MVR sodium chloride falling film concentration unit is connected to the MVR sodium chloride evaporation and crystallization unit. The MVR sodium chloride crystallization device is used for sodium chloride crystallization and separation, and the concentrate outlet of the MVR sodium chloride crystallization device is connected to the potassium chloride cooling crystallization device. The potassium chloride cooling crystallization device is used for potassium chloride crystallization and separation, and the concentrated water outlet of the potassium chloride cooling crystallization device is also connected to the mother liquor drying device.

2. The high-salinity wastewater desalination resource utilization treatment system according to claim 1, characterized in that, The frozen mother liquor purification device and the frozen mother liquor NF device decolorize the mother liquor and remove organic matter by adding a strong oxidant. The frozen mother liquor NF device recovers monovalent salts from the frozen mother liquor, thereby reducing the scale of mother liquor drying treatment and the amount of impurities.

3. The high-salinity wastewater desalination resource utilization treatment system according to claim 1, characterized in that, The MVR sodium chloride crystallization unit and potassium chloride cooling crystallization unit are equipped with an improved OSLO crystallizer. By increasing the size of the central circulation pipe of the OSLO crystallizer, the downward flow velocity of the central circulation pipe is reduced to below 0.5 m / s, and a salt leg is added to realize the grading, washing and crystallization of sodium chloride crystallized salt.

4. The high-salinity wastewater desalination resource utilization treatment system according to claim 1, characterized in that, The potassium chloride cooling crystallization device includes a multi-stage continuous cooling crystallization unit for potassium chloride, enabling automated continuous crystallization.

5. The high-salinity wastewater desalination resource recovery treatment system according to claim 4, characterized in that, The potassium chloride cooling crystallization device includes a potassium chloride flash evaporator, a potassium chloride crystallizer, a potassium chloride slurry tank, a potassium chloride thickener, a potassium chloride centrifuge, and a potassium chloride mother liquor tank; The potassium chloride flash chamber is used for primary cooling of potassium chloride, and its outlet is connected to the potassium chloride crystallizer. The potassium chloride crystallizer is used for secondary cooling and primary crystallization of potassium chloride, and its outlet is connected to the potassium chloride crystal slurry tank. The potassium chloride crystal slurry tank is used to eliminate the boiling point rise of potassium chloride, and its outlet is connected to the potassium chloride thickener. The potassium chloride thickener is used to increase the solid-liquid ratio of the potassium chloride output. Its outlet is connected to the potassium chloride centrifuge, and the supernatant overflow is connected to the potassium chloride mother liquor tank. The potassium chloride centrifuge is used for solid-liquid separation of potassium chloride crystallized salt. The crystallized salt enters the crystallized salt packaging machine, and the centrifugal mother liquor is connected to the potassium chloride mother liquor tank. The potassium chloride mother liquor tank is used to collect potassium chloride thickener and centrifuged mother liquor, and its outlet is connected to the MVR sodium chloride evaporation and crystallization device and the mother liquor drying device.

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