Vibration filter membrane system capable of reducing strontium scaling of evaporation crystallizer

Abstract

The invention discloses a vibration filter membrane system capable of reducing strontium scaling of an evaporation crystallizer, comprising: a reaction tank, which is used for adding sodium carbonate therein to treat mine water to generate strontium carbonate precipitate, and is internally provided with a stirring device; the filter unit is provided with a vibrator as well as a first flat sheet membrane and a second flat sheet membrane which are arranged at different heights, a region between the first flat sheet membrane and the second flat sheet membrane is filled with resin capable of adsorbing strontium ions, and the vibrator is mounted at the bottom of the first flat sheet membrane; the pressure pump is used for conveying effluent of the reaction tank to the filtering unit, and when the pressure difference between the first flat sheet membrane and the second flat sheet membrane exceeds a certain pressure difference, the vibrator is triggered to be started; and the resin replacement unit is used for filling a region between the first flat sheet membrane and the second flat sheet membrane with new resin or discharging saturated resin in the region. According to the method, the strontium ion content of 1-100 mg / L of inlet mine water is reduced to 0.01-1 mg / L after treatment, and generation of strontium sulfate scale in a tail end evaporation crystallizer is reduced from the source.

Description

Technical Field

[0001] This invention relates to the field of mine water treatment technology, and more specifically, to a vibrating filter membrane system that can reduce strontium scaling in evaporation crystallizers. Background Technology

[0002] In advanced mine water treatment and zero-discharge processes, nanofiltration brine, rich in strontium ions (often ranging from 1-100 mg / L), readily combines with sulfate ions to form strontium sulfate scale after entering the terminal evaporator crystallizer under high-temperature conditions. Strontium sulfate scale is hard and difficult to remove completely using conventional cleaning methods, increasing equipment maintenance costs and downtime. Furthermore, as the scale thickness increases, the crystallizer's heat exchange efficiency significantly decreases. Statistics show that when the scale thickness reaches 1 mm, heat exchange efficiency can decrease by 15%-25%, leading to a significant increase in system energy consumption and severely impacting the economic viability and stability of the zero-discharge mine water process.

[0003] In existing treatment technologies, chemical precipitation can remove some strontium ions, but it is difficult to reduce the concentration to below 1 mg / L. Traditional single-layer filter membrane adsorption technology has problems such as low resin utilization and rapid membrane fouling. Moreover, when strontium carbonate and other precipitates adhere to the membrane surface, causing the pressure difference to rise, frequent shutdowns for cleaning are required, which cannot meet the requirements for continuous operation. Summary of the Invention

[0004] Based on this, the main objective of this invention is to overcome the shortcomings of existing treatment methods and provide a vibrating filter membrane system that can reduce strontium scaling in evaporation crystallizers. For strontium ion concentrations of 1-100 mg / L inlet mine water, it can stably output 0.01-1 mg / L of treated water and effectively solve the problems of membrane fouling and resin replacement.

[0005] To achieve the above objectives, the present invention provides a vibrating filter membrane system that can reduce strontium fouling in evaporator crystallizers, comprising:

[0006] A reaction tank for adding sodium carbonate to treat mine water to produce strontium carbonate precipitate; the reaction tank is equipped with a stirring device.

[0007] A filtration unit is used to receive and filter the effluent from the reaction tank. The filtration unit has a first flat sheet membrane and a second flat sheet membrane set at different heights for water to pass through sequentially. The area between the first flat sheet membrane and the second flat sheet membrane is filled with resin that can adsorb strontium ions. A vibrator is installed at the bottom of the first flat sheet membrane to vibrate down the coagulants intercepted on the surface of the first flat sheet membrane so that they are removed from the first flat sheet membrane. When a certain pressure difference is exceeded between the first flat sheet membrane and the second flat sheet membrane of the filtration unit, the vibrator is activated.

[0008] A booster pump is used to transport the effluent from the reaction tank to the filtration unit;

[0009] The resin replacement unit is connected to the area between the first and second flat sheet membranes of the filtration unit, and is used to fill the area with new resin or to discharge saturated resin from the area.

[0010] Furthermore, it also includes a sewage pump, with a first sewage outlet at the bottom of the reaction tank and a second sewage outlet at the bottom of the filter unit, the first and second sewage outlets being connected to the sewage pump.

[0011] Furthermore, the resin replacement unit includes a resin storage tank, a transfer pump, and a resin discharge valve. During resin filling, the new resin is transported from the storage tank to the space between the first flat sheet membrane and the second flat sheet membrane via the transfer pump. The saturated resin is discharged from the space between the first flat sheet membrane and the second flat sheet membrane via the resin discharge valve using a drain pump.

[0012] Furthermore, the system also includes a control unit, which is electrically connected to the stirring device, the pressurizing pump, the vibrator, the resin replacement unit, and the sewage pump, respectively, and is used to control the operating parameters and operating status of each device.

[0013] Furthermore, the control unit includes a sensor module, a data processing module, and an execution module. The sensor module includes a strontium ion concentration sensor, a flow sensor, and a pressure sensor, respectively installed on the mine water inlet side and the mine water production side. The data processing module is used to receive data from the sensor module and calculate the sodium carbonate dosage, the vibrator start-up timing, and the resin replacement cycle. The execution module is used to control the operation of each device according to the instructions from the data processing module.

[0014] Furthermore, the stirring device in the reaction tank is a paddle stirrer, the stirring speed of which is adjustable in the range of 50-200 r / min, the diameter of the stirrer blade is 1 / 3-1 / 2 of the diameter of the reaction tank, and the stirring time is 15-60 min.

[0015] Furthermore, the vibrator is an electromagnetic vibrator, whose vibration frequency can be adjusted within the range of 15-60Hz, vibration amplitude can be adjusted within the range of 1-8mm, single vibration duration is 30s-5min, and after vibration, the pressure difference between the inlet and outlet of the filter membrane recovers to 0.02-0.08MPa.

[0016] Furthermore, the angle between the first flat sheet membrane and the bottom of the filter unit is between 30° and 70°, and the angle between the second flat sheet membrane and the bottom of the filter unit is between 30° and 70°.

[0017] Furthermore, the pore size of the first and second flat sheet membranes is 0.01-0.1 μm, and the effective filtration area of ​​a single membrane is 0.5-5 m². 2The distance between the first and second flat sheet membranes is 5-20mm. The membrane material is polyvinylidene fluoride, polypropylene, or polyethylene, and the membrane surface is hydrophilic modified, with a water contact angle ≤60°.

[0018] Furthermore, the resin capable of adsorbing strontium ions is an iminodiacetic acid type chelating resin or a phosphate ester type chelating resin, with a resin particle size of 0.3-1.2 mm and an exchange capacity of 1.0-2.0 mmol / g. The resin filling amount between the double-layer flat membrane is 0.5-3 kg per square meter of membrane area. When the resin adsorption capacity reaches 80%-90% of the saturation capacity, the resin is discharged and new resin is filled.

[0019] Furthermore, the sewage pump is a pneumatic diaphragm pump with a head of 5-20m and a flow rate of 1-20m³. 3 / h, and the start of the sewage pump is linked to the vibration cycle of the vibrator. The sewage pump is started within 10-30 minutes after the vibration ends to discharge the sediment.

[0020] The beneficial effects of this invention are as follows:

[0021] This invention provides a vibrating membrane filtration system that reduces strontium scaling in evaporator crystallizers. The system includes a reaction tank with a stirring device, a filtration unit with a vibrator and first and second flat plate membranes, a pressurizing pump, and a resin replacement unit. Specifically, sodium carbonate is added to the reaction tank at a 1:1 ratio based on the strontium ion content of 1-100 mg / L in the inlet mine water. Stirring allows the sodium carbonate to fully react with the strontium ions, generating strontium carbonate precipitate. The effluent from the reaction enters the filtration unit and passes through the first and second flat plate membranes, along with the strontium-adsorbing resin filling the space between them, to adsorb any remaining strontium ions. The vibrator is used to dislodge the precipitate adhering to the membrane surface when the pressure difference between the first and second flat plate membranes is too high. The resin replacement unit is used to discharge saturated resin and refill with new resin after the resin has reached saturation. Simultaneously, a wastewater pump can be used to discharge the saturated resin, the strontium carbonate precipitate at the bottom of the reaction tank, and the precipitate dislodged from the membrane surface.

[0022] Based on the above-described system and process of this invention, the present invention achieves the following technical effects:

[0023] 1. Precise control of strontium ion concentration: For mine water with an inlet strontium ion concentration of 1-100 mg / L, the outlet concentration can be stably controlled at 0.01-1 mg / L through a dual mechanism of "1:1 sodium carbonate precipitation + resin adsorption between double-layer membranes (first flat plate membrane and second flat plate membrane)", with a removal rate of up to 99%-99.99%, thus eliminating the formation of strontium sulfate scale in the evaporator crystallizer from the source.

[0024] 2. Online mitigation of membrane fouling: The vibrator at the bottom of the membrane automatically starts when the pressure difference is too high. The vibration with an amplitude of 1-8mm can quickly shake off the deposits on the membrane surface and restore the filter flux within 30s-5min. No need to stop the machine for cleaning, and the continuous operation rate of the system is increased to over 95%.

[0025] 3. High-efficiency automated resin replacement: The resin replacement unit enables rapid discharge of saturated resin and filling with new resin, with a total time of ≤30 minutes. It also supports switching to a backup unit to avoid processing interruptions.

[0026] 4. Low energy consumption and maintenance costs: After reducing strontium sulfate scale, the heat exchange efficiency of the evaporator crystallizer is maintained at more than 90% of the design value, and energy consumption is reduced by 15%-25%; vibration cleaning and automatic resin replacement reduce manual operation, and annual maintenance costs are reduced by 30%-40%.

[0027] 5. High adaptability: The stirring speed, vibration parameters, and resin filling amount can be flexibly adjusted according to the inlet strontium ion concentration (1-100mg / L), making it suitable for different mine water quality conditions and with a wide range of applications. It is especially suitable for the treatment of concentrated brine in the nanofiltration process of zero discharge of mine water membrane.

[0028] Other features and advantages of the present invention will be described in detail through the following specific embodiments. Attached Figure Description

[0029] Figure 1 This invention provides a vibrating filter membrane system that can reduce strontium scaling in evaporator crystallizers.

[0030] The diagram is labeled as follows: 1-Reaction tank, 1.1-Stirring device, 1.2-First drain outlet, 2-Pressure pump, 3-Filter unit, 3.1 Vibrator, 3.2-First flat sheet membrane, 3.3-Second flat sheet membrane, 3.4-Resin, 3.5-Resin replacement inlet, 3.6-Second drain outlet, 4-Resin replacement unit, 4.1-Resin storage tank, 4.2-Resin discharge valve, 4.3-Resin transfer pump, 5-Sewage pump. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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 the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0033] Unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components or interactions between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0034] This invention aims to overcome the problems in existing mine water treatment systems, such as the difficulty in reducing strontium ion concentrations from 1-100 mg / L at the inlet to 0.01-1 mg / L, the tendency of filter membranes to have excessively high pressure differentials due to sediment buildup, and the low efficiency of resin replacement. It provides a vibrating filter membrane system that can reduce strontium scaling in evaporators and crystallizers, achieving efficient removal of strontium ions, online mitigation of membrane fouling, and automated resin replacement, thus ensuring stable operation of the evaporator and crystallizer.

[0035] like Figure 1 As shown, a vibrating filter membrane system for reducing strontium fouling in an evaporator crystallizer includes:

[0036] A reaction tank for adding sodium carbonate to treat mine water to produce strontium carbonate precipitate; the reaction tank is equipped with a stirring device.

[0037] A filtration unit is used to receive and filter the effluent from the reaction tank. The filtration unit has a first flat sheet membrane and a second flat sheet membrane set at different heights for water to pass through sequentially. The area between the first flat sheet membrane and the second flat sheet membrane is filled with resin that can adsorb strontium ions. A vibrator is installed at the bottom of the first flat sheet membrane to vibrate down the coagulants intercepted on the surface of the first flat sheet membrane so that they are removed from the first flat sheet membrane. When a certain pressure difference is exceeded between the first flat sheet membrane and the second flat sheet membrane of the filtration unit, the vibrator is activated.

[0038] A booster pump is used to transport the effluent from the reaction tank to the filtration unit;

[0039] The resin replacement unit is connected to the area between the first and second flat sheet membranes of the filtration unit, and is used to fill the area with new resin or to discharge saturated resin from the area.

[0040] In this invention, mine water enters the reaction tank from the inlet side. Sodium carbonate is added to the reaction tank at a ratio of 1:1 (the molar ratio of sodium carbonate to strontium ions) according to the strontium ion content of 1-100 mg / L in the inlet mine water. After stirring and reaction, strontium carbonate precipitate is generated.

[0041] In some specific embodiments, the stirring device in the reaction tank is a paddle stirrer. The stirring speed of the paddle stirrer in the reaction tank is 50-200 r / min, and the diameter of the paddle is 1 / 3-1 / 2 of the diameter of the reaction tank. Stirring for 15-60 min can ensure that the conversion rate of sodium carbonate and strontium ions is ≥90%, and initially reduce the strontium ion concentration to 10-20 mg / L, laying the foundation for subsequent resin adsorption.

[0042] In some specific embodiments, the resin replacement unit includes a resin storage tank, a resin transfer pump (flow rate 0.5-15 L / h), and a resin discharge valve. During resin filling, new resin is transported from the storage tank to the space between the first and second flat sheet membranes through the resin renewal inlet. During resin discharge, the saturated resin is transported from the space between the first and second flat sheet membranes to the sludge system through the resin discharge valve and the sludge pump. This invention allows for resin replacement via pump and valve switching, completing the "saturated resin discharge - new resin filling" process within ≤30 minutes. Furthermore, the system can maintain continuous operation during replacement using a backup filtration unit, eliminating downtime losses.

[0043] In some specific embodiments, the pore size of the first and second flat sheet membranes is 0.01-0.1 μm, and the effective filtration area of ​​a single membrane is 0.5-5 m². 2 The distance between the first and second flat sheet membranes through which the mine water flows is 5-20mm. The membrane material is polyvinylidene fluoride, polypropylene, or polyethylene, and the membrane surface is treated with hydrophilicity modification, with a water contact angle ≤60° to reduce the tendency of sediment adhesion.

[0044] In some specific embodiments, the angle between the first flat sheet membrane and the bottom of the filtration unit (e.g., the filtration tank) is between 30° and 70°, and the angle between the second flat sheet membrane and the bottom of the filtration unit (e.g., the filtration tank) is also between 30° and 70°. This angle allows the upper part of the flat sheet membrane to intercept coagulants in the water and allow them to slide down to the bottom of the tank by gravity, while also preventing excessive pressure on the membrane surface and minimizing wear. Since the coagulants are mainly intercepted by the first flat sheet membrane, the vibrator is installed at the bottom of the first flat sheet membrane.

[0045] In some specific embodiments, the resin capable of adsorbing strontium ions is an iminodiacetic acid-type chelating resin or a phosphate ester-type chelating resin. The resin has a particle size of 0.3-1.2 mm and an exchange capacity of 1.0-2.0 mmol / g. The resin filling amount between the double-layer flat sheet membrane is 0.5-3 kg per square meter of membrane area, which can efficiently adsorb residual strontium ions and further reduce the concentration from 10-20 mg / L to 0.01-1 mg / L.

[0046] In some specific implementations, when the resin adsorption capacity reaches 80%-90% of the saturation capacity, the saturated resin is discharged and new resin is added.

[0047] In some specific embodiments, the vibrator is an electromagnetic vibrator, whose vibration frequency can be adjusted in the range of 15-60Hz, vibration amplitude can be adjusted in the range of 1-8mm, single vibration duration is 30s-5min, and after vibration, the pressure difference between the inlet and outlet of the filter membrane of the filter unit recovers to 0.02-0.08MPa.

[0048] In some specific embodiments, the bottom of the reaction tank and the filtration unit are respectively provided with sewage outlets, which are connected to sewage pumps.

[0049] In some specific implementations, the booster pump is used for liquid level control of the filter unit; when the liquid level is low, the booster pump is started to allow water to enter, and when the liquid level is high, the booster pump is stopped.

[0050] In some specific embodiments, the sewage pump is a pneumatic diaphragm pump with a head of 5-20m and a flow rate of 1-20m³. 3 / h, and the start of the sewage pump is linked to the vibration cycle of the vibrator. The sewage pump is started within 10-30 minutes after the vibration ends to discharge the sediment, ensuring that the sediment from the vibration is discharged in time and avoiding secondary adhesion.

[0051] In some specific embodiments, the system further includes a control unit, which is electrically connected to the stirring device, pressurizing pump, vibrator, resin replacement unit, and sewage pump, respectively, for controlling the operating parameters and operating status of each device. The control unit can automatically adjust the dosage of sodium carbonate according to the strontium ion concentration of the inlet mine water (1-100 mg / L), and adjust the resin filling frequency based on the strontium ion concentration of the outlet mine water (target 0.01-1 mg / L).

[0052] In some specific embodiments, the control unit includes a sensor module, a data processing module, and an execution module. The sensor module includes strontium ion concentration sensors (detection range 0.001-200 mg / L) installed on the mine water inlet and product water sides respectively, as well as flow sensors that can be installed on the inlet and outlet pipes of the filtration unit, and pressure sensors that can be installed on the first and second flat sheet membranes. The data processing module is used to receive data from the sensor module and calculate the sodium carbonate dosage, vibrator start-up timing, and resin replacement cycle. The execution module is used to control the operation of each device according to the instructions of the data processing module to ensure that the strontium ion content of the outlet mine water is stable at 0.01-1 mg / L.

[0053] In some specific implementations, the booster pump has a head of 10-30m and a flow rate of 5-50m³ / h. 3 / h, both the first and second flat sheet membranes are equipped with pressure monitoring points. When the pressure difference is >0.1-0.3MPa, the control unit automatically triggers the bottom electromagnetic vibrator (frequency 15-60Hz, amplitude 1-8mm) to start. After a single vibration of 30s-5min, the pressure difference can be restored to 0.02-0.08MPa, which can alleviate membrane fouling without stopping the machine.

[0054] In this invention, the control unit acquires data through the strontium ion concentration sensor on the inlet side, automatically calculates and adds sodium carbonate at a 1:1 ratio; the strontium ion concentration sensor on the product water side monitors the treatment effect in real time. If the concentration is >1mg / L, it indicates that the resin adsorption is saturated, and feedback is sent to the system to replace the resin to ensure stable treatment effect in all aspects.

[0055] The present invention will be further illustrated by the following examples, but the present invention is not limited thereto.

[0056] Example 1 (Low-concentration inlet mine water treatment)

[0057] Treatment target: Strontium ion concentration in inlet mine water 1-10 mg / L, target outlet concentration 0.01-0.5 mg / L.

[0058] System Configuration:

[0059] Reaction tank: Paddle agitator (paddle diameter is 1 / 3 of the reaction tank diameter, stirring speed is 50-80 r / min, stirring time is 15-30 min), sodium carbonate is added at a ratio of 1:1 according to the strontium ion content of the inlet mine water, and the strontium ion concentration drops to 1-2 mg / L after the reaction.

[0060] Booster pump: Head 10-15m, Flow rate 5-15m³ / h 3 / h, the pressure difference threshold between the inlet and outlet of the filter unit is set to 0.1MPa.

[0061] First and second sheet films: PVDF material, pore size 0.01μm, single sheet area 0.5-2m² 2 The two membrane layers are spaced 5-10 mm apart, with hydrophilic surface modification. The angle between the surfaces of the first and second flat sheet membranes and the bottom of the pool is 50°. The membrane space is filled with 0.3-0.6 mm of iminodiacetic acid-type chelating resin (exchange capacity 1.0 mmol / g), with a filling amount of 0.5-1 kg / m³. 2 Membrane area.

[0062] Vibrator: Electromagnetic type, frequency 15-30Hz, amplitude 1-3mm, single vibration 30s-1min, pressure difference recovers to 0.07-0.09MPa after vibration.

[0063] Resin replacement unit: transfer pump flow rate 0.5-3L / h, resin replacement cycle 7-10 days (when strontium ion concentration in product water > 1mg / L), replacement time 15-20min.

[0064] Bottom sewage pump: Head 5-10m, flow rate 1-5m³ / h 3 / h, start 10 minutes after vibration.

[0065] Operational results: After 30 days of continuous operation, the strontium ion concentration in the outlet mine water remained stable at 0.01-0.4 mg / L, with an average removal rate of 99.6%. When the filter membrane pressure difference exceeded 0.1 MPa, it returned to normal within 30 seconds to 1 minute after the vibrator was started, without any downtime for cleaning. There was no interruption in the resin replacement process, and the sludge discharge was reduced by 20% compared to the traditional process.

[0066] Example 2 (High-concentration inlet mine water treatment)

[0067] Treatment target: Strontium ion concentration in inlet mine water 50-100 mg / L, target outlet concentration 0.5-1 mg / L.

[0068] System Configuration:

[0069] Reaction tank: Paddle agitator (paddle diameter is 1 / 2 of the reaction tank diameter, stirring speed is 150-200 r / min, stirring time is 45-60 min), sodium carbonate is added at a ratio of 1:1 according to the strontium ion content of the inlet mine water, and the strontium ion concentration drops to 10-20 mg / L after the reaction.

[0070] Booster pump: Head 25-30m, flow rate 30-50m³ / h 3 / h, the pressure difference threshold between the inlet and outlet of the filter unit is set to 0.3MPa.

[0071] First and second sheet films: PE material, pore size 0.1μm, single sheet area 3-5m² 2The membrane spacing is 15-20 mm, the surface is hydrophilically modified, and the angle between the membrane surface and the bottom of the pool is 45°; the membrane space is filled with 0.8-1.2 mm of phosphate ester chelating resin (exchange capacity 2.0 mmol / g), with a packing amount of 2-3 kg / m³. 2 Membrane area.

[0072] Vibrator: Electromagnetic type, frequency 45-60Hz, amplitude 6-8mm, single vibration 3-5min, pressure difference recovers to 0.02-0.04MPa after vibration.

[0073] Resin replacement unit: The transfer pump flow rate is 10-15L / h, the resin replacement cycle is 3-5 days (when the strontium ion concentration in the product water is >1mg / L), the replacement time is 25-30min, and a backup filter unit is provided to achieve continuous operation.

[0074] Bottom sewage pump: Head 15-20m, Flow rate 15-20m³ / h 3 / h, start 25-30 minutes after vibration.

[0075] Operational results: After 30 days of continuous operation, the strontium ion concentration in the outlet mine water remained stable at 0.5-0.9 mg / L, with an average removal rate of 99.2%. When the filter membrane pressure difference exceeded 0.3 MPa, the vibrator returned to normal after 3-5 minutes of startup, and the membrane flux remained above 92% of the initial value. The standby unit switching was smooth, the resin replacement was uninterrupted, no strontium sulfate scale deposition occurred in the evaporator crystallizer, and the heat exchange efficiency was stable.

[0076] Example 3 (Medium-concentration inlet mine water treatment)

[0077] Treatment target: Strontium ion concentration in inlet mine water of 20-50 mg / L, target outlet concentration of 0.1-0.8 mg / L.

[0078] System Configuration:

[0079] Reaction tank: Paddle stirrer (paddle diameter is 1 / 2 of the reaction tank diameter, stirring speed is 100-150 r / min, stirring time is 30-45 min), after the reaction the strontium ion concentration drops to 5-10 mg / L.

[0080] Booster pump: Head 18-22m, Flow rate 20-30m³ / h 3 / h, the pressure difference threshold between the inlet and outlet of the filter unit is 0.2MPa.

[0081] First and second sheet films: PP material, pore size 0.05μm, single sheet area 2-4m² 2The membrane spacing is 10-15 mm, the surface is hydrophilically modified, and the angle between the membrane surface and the bottom of the pool is 55°; the membrane spacer is filled with 0.6-0.9 mm of iminodiacetic acid type chelating resin (exchange capacity 1.5 mmol / g), and the packing amount is 1.5-2 kg / m³. 2 Membrane area.

[0082] Vibrator: Electromagnetic type, frequency 30-45Hz, amplitude 4-6mm, single vibration 2-3min, pressure difference recovers to 0.04-0.07MPa after vibration.

[0083] Resin replacement unit: The transfer pump flow rate is 5-8L / h, and the resin replacement cycle is 5-7 days. When the strontium ion concentration in the product water is >1mg / L, the resin should be replaced, which takes 20-25 minutes.

[0084] Bottom sewage pump: Head 10-17m, Flow rate 10-15m³ / h 3 / h, start 10-13 minutes after vibration.

[0085] Operating results: Strontium ion concentration at the outlet is 0.1-0.7 mg / L, with a removal rate of 99.4%; the filter membrane pressure differential recovery efficiency is high, the resin replacement is convenient, and the overall energy consumption of the system is reduced by 22% compared with the traditional process.

[0086] Although the present invention has been described in detail through the preferred embodiments described above, it should be understood that the above description should not be considered as a limitation of the present invention. Those skilled in the art will understand that modifications or adjustments can be made to the present invention based on the teachings of this specification. These modifications or adjustments should also be within the scope defined by the claims of the present invention.

Claims

1. A vibrating filter membrane system for reducing strontium fouling in an evaporator crystallizer, characterized in that, include: A reaction tank for adding sodium carbonate to treat mine water to produce strontium carbonate precipitate; the reaction tank is equipped with a stirring device. A filtration unit is used to receive and filter the effluent from the reaction tank. The filtration unit has a first flat sheet membrane and a second flat sheet membrane set at different heights for water to pass through sequentially. The area between the first flat sheet membrane and the second flat sheet membrane is filled with resin that can adsorb strontium ions. A vibrator is installed at the bottom of the first flat sheet membrane to vibrate down the coagulants intercepted on the surface of the first flat sheet membrane so that they are removed from the first flat sheet membrane. When a certain pressure difference is exceeded between the first flat sheet membrane and the second flat sheet membrane of the filtration unit, the vibrator is activated. A booster pump is used to transport the effluent from the reaction tank to the filtration unit; The resin replacement unit is connected to the area between the first and second flat sheet membranes of the filtration unit, and is used to fill the area with new resin or to discharge saturated resin from the area.

2. The vibrating filter membrane system for reducing strontium scaling in evaporator crystallizers according to claim 1, characterized in that, The system also includes a sewage pump, a first sewage outlet is provided at the bottom of the reaction tank and a second sewage outlet is provided at the bottom of the filter unit, and the first sewage outlet and the second sewage outlet are connected to the sewage pump.

3. The vibrating filter membrane system for reducing strontium scaling in evaporator crystallizers according to claim 2, characterized in that, The resin replacement unit includes a resin storage tank, a transfer pump, and a resin discharge valve. When filling the resin, the new resin is transported from the storage tank to the space between the first flat sheet membrane and the second flat sheet membrane by the transfer pump. The saturated resin is discharged from the space between the first flat sheet membrane and the second flat sheet membrane by the sewage pump through the resin discharge valve.

4. The vibrating filter membrane system for reducing strontium scaling in evaporator crystallizers according to claim 2, characterized in that, The system also includes a control unit, which is electrically connected to the stirring device, the pressurizing pump, the vibrator, the resin replacement unit, and the sewage pump, respectively, and is used to control the operating parameters and operating status of each device.

5. The vibrating filter membrane system for reducing strontium fouling in evaporator crystallizers according to claim 1, characterized in that, The control unit includes a sensor module, a data processing module, and an execution module. The sensor module includes a strontium ion concentration sensor, a flow sensor, and a pressure sensor, respectively installed on the mine water inlet side and the mine water production side. The data processing module is used to receive data from the sensor module and calculate the sodium carbonate dosage, the vibrator start-up timing, and the resin replacement cycle. The execution module is used to control the operation of each device according to the instructions from the data processing module.

6. The vibrating filter membrane system for reducing strontium fouling in evaporator crystallizers according to claim 1, characterized in that, The stirring device in the reaction tank is a paddle stirrer. The stirring speed of the paddle stirrer is adjustable in the range of 50-200 r / min. The diameter of the stirrer blade is 1 / 3-1 / 2 of the diameter of the reaction tank. The stirring time is 15-60 min.

7. The vibrating filter membrane system for reducing strontium scaling in evaporator crystallizers according to claim 1, characterized in that, The vibrator is an electromagnetic vibrator, whose vibration frequency can be adjusted in the range of 15-60Hz, vibration amplitude can be adjusted in the range of 1-8mm, single vibration duration is 30s-5min, and after vibration the pressure difference between the inlet and outlet of the filter membrane recovers to 0.02-0.08MPa.

8. The vibrating filter membrane system for reducing strontium scaling in evaporator crystallizers according to claim 1, characterized in that, The angle between the first sheet membrane and the bottom of the filter unit is between 30° and 70°, and the angle between the second sheet membrane and the bottom of the filter unit is also between 30° and 70°. The pore size of the first and second sheet membranes is 0.01-0.1 μm, and the effective filtration area of ​​a single membrane is 0.5-5 m². 2 The distance between the first and second flat sheet membranes is 5-20mm. The membrane material is polyvinylidene fluoride, polypropylene, or polyethylene, and the membrane surface is hydrophilic modified, with a water contact angle ≤60°.

9. The vibrating filter membrane system for reducing strontium scaling in evaporator crystallizers according to claim 1, characterized in that, The resin that can adsorb strontium ions is an iminodiacetic acid type chelating resin or a phosphate ester type chelating resin. The resin has a particle size of 0.3-1.2 mm and an exchange capacity of 1.0-2.0 mmol / g. The amount of resin filling between the double-layer flat membrane is 0.5-3 kg per square meter of membrane area. When the resin adsorption capacity reaches 80%-90% of the saturation capacity, the resin is discharged and new resin is filled.

10. The vibrating filter membrane system for reducing strontium fouling in an evaporator crystallizer according to claim 1, characterized in that, The sewage pump is a pneumatic diaphragm pump with a head of 5-20m and a flow rate of 1-20m³ / h. 3 / h, and the start of the sewage pump is linked to the vibration cycle of the vibrator. The sewage pump is started within 10-30 minutes after the vibration ends to discharge the sediment.

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