Ceramic membrane equipment for purifying nano powder

Abstract

The utility model discloses ceramic membrane equipment for purifying nano powder. The ceramic membrane equipment comprises a cleaning tank, a dispersing tank and a ceramic membrane component, the output end of the cleaning tank is communicated with the input end of the ceramic membrane component through a material conveying pipeline; a material conveying pump is arranged on the material conveying pipeline; a concentrated solution pipeline is connected to one end, for outputting concentrated solution, of the ceramic membrane assembly, a dialysate pipeline is connected to one end, for outputting dialysate, of the ceramic membrane assembly, and a first control valve is arranged on the concentrated solution pipeline; the input end of the dispersing tank is communicated with the concentrated solution pipeline through a first backflow pipeline, the communicated position is located between the first control valve and the ceramic membrane assembly, and the output end of the dispersing tank is communicated with the cleaning tank through a second backflow pipeline; a second control valve is arranged on the first backflow pipeline, and an ultrasonic generating device is arranged in the dispersing tank. When the ultrasonic dispersion device is used, a concentrated solution can be guided to flow back into the dispersion tank, and the powder is quickly and uniformly mixed and dispersed by the ultrasonic generation device arranged in the dispersion tank, so that the agglomeration of the nano powder is reduced, and the granularity uniformity of the nano powder is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of membrane separation, in particular to a ceramic membrane device for purifying nano powders. Background Art

[0002] Nanopowders, also known as nanoparticles and ultrafine particles, refer to a type of metastable intermediate substance between solids and molecules with extremely small particle sizes (1-100nm). At present, nanopowders are mainly prepared by wet chemical methods in China. During the preparation process, different chemical reagents are added to react, and finally an ultrafine product slurry with a large amount of impurity ions is obtained.

[0003] The obtained ultrafine product slurry needs to be washed and purified later. Traditional nano powder washing methods include centrifugation, rinsing, membrane separation, chemical precipitation, etc., which can effectively remove impurity ions and improve product purity. However, in the process of separation and purification using traditional methods, there are problems such as nano powder agglomeration, large powder particle size, large washing water volume, fast membrane contamination and long cleaning cycle, low nano powder recovery rate, and difficult purification. Utility Model Content

[0004] The utility model aims to provide a ceramic membrane device for purifying nano powders, so as to wash and purify the nano powders and reduce the agglomeration of the nano powders.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0006] A ceramic membrane device for purifying nano powders comprises a cleaning tank, a dispersion tank and a ceramic membrane assembly; the output end of the cleaning tank is connected to the input end of the ceramic membrane assembly through a feed pipeline, and a feed pump is arranged on the feed pipeline; one end of the ceramic membrane assembly outputting concentrated liquid is connected to a concentrated liquid pipeline, and one end outputting dialysate is connected to a dialysate pipeline, and a first control valve is arranged on the concentrated liquid pipeline; the input end of the dispersion tank is connected to the concentrated liquid pipeline through a first reflux pipeline, and the mutually connected position is located between the first control valve and the ceramic membrane assembly, and the output end of the dispersion tank is connected to the cleaning tank through a second reflux pipeline; a second control valve is arranged on the first reflux pipeline, and an ultrasonic generating device is arranged in the dispersion tank.

[0007] Furthermore, it also includes a circulation pump and an internal circulation pipeline, the circulation pump is arranged on the feed pipeline and is located between the feed pump and the ceramic membrane assembly, one end of the internal circulation pipeline is connected to the concentrated liquid pipeline, and the other end is connected to the feed pipeline, and the mutually connected position is located between the feed pump and the circulation pump.

[0008] Furthermore, it also includes a Y-type filter, which is arranged on the material conveying pipeline.

[0009] Furthermore, a third control valve is provided on the dialysate pipeline, and is connected to the cleaning tank via a third return pipeline. The position where the third return pipeline and the dialysate pipeline are interconnected is located between the third control valve and the ceramic membrane assembly, and a fourth control valve is provided on the third return pipeline.

[0010] Furthermore, a fifth control valve and a backwash tank are provided on the dialysate pipeline, and the backwash tank is located between the fifth control valve and the ceramic membrane assembly. The backwash tank or the dialysate pipeline is externally connected to a compressed air pipeline at a portion between the backwash tank and the fifth control valve. A sixth control valve is provided on the compressed air pipeline and is connected to an air compressor.

[0011] Furthermore, an exhaust pipeline is connected between one end of the ceramic membrane assembly that outputs the concentrated liquid and the concentrated liquid pipeline, and an exhaust valve is provided on the exhaust pipeline.

[0012] Furthermore, a sewage discharge pipeline is connected to the bottom of the cleaning tank, and a sewage discharge valve is arranged on the sewage discharge pipeline.

[0013] Furthermore, the feed pipeline is provided with a temperature gauge and a first pressure gauge, the concentrate pipeline is provided with a second pressure gauge, a pressure regulating valve and a first flow meter, and the dialysate pipeline is provided with a second flow meter.

[0014] Furthermore, sampling valves are provided on the concentrated liquid pipeline and the dialysate pipeline.

[0015] Furthermore, two groups of the ceramic membrane components are arranged in series.

[0016] The utility model has the following beneficial effects:

[0017] 1. The utility model provides a ceramic membrane device for purifying nano powders. The device is provided with a dispersion tank and an ultrasonic generator. When in use, the concentrated liquid can be guided from the concentrated liquid pipeline into the dispersion tank through the first reflux pipeline, and the ultrasonic generator arranged in the dispersion tank can quickly mix and break up the powder to reduce the agglomeration of the nano powder. The nano powder after breaking up can be guided back to the cleaning tank through the second reflux pipeline for washing again. The particle size uniformity of the nano powder after washing and purification is better.

[0018] 2. The utility model provides a ceramic membrane device for purifying nano powders. A circulation pump and an internal circulation pipeline are arranged in the device. When in use, the ceramic membrane assembly can be used to circulate and purify nano powders, thereby improving the purification efficiency of nano powders.

[0019] 3. The utility model provides a ceramic membrane device for purifying nano powders. The device is provided with a backwash tank and a compressed air pipeline. The dialysate can be used to backwash the ceramic membrane assembly, thereby slowing down the pollution and clogging speed of the membrane core of the ceramic membrane assembly and improving the purification quality of the nano powders. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the utility model.

[0021] Main component symbol description: 1. Cleaning tank; 2. Heat exchange interlayer; 3. Cooling water inlet; 4. Cooling water outlet; 5. Ceramic membrane assembly; 6. Dispersion tank; 7. Ultrasonic generator; 8. Backwash tank; 9. Feed pipeline; 10. Drain pipeline; 11. Concentrate pipeline; 12. First return pipeline; 13. Second return pipeline; 14. Internal circulation pipeline; 15. Compressed air pipeline; 16. Exhaust pipeline; 17. Dialysate pipeline; 18. Third return pipeline; 19. , feed pump; 20, circulation pump; 21, first control valve; 22, second control valve; 23, third control valve; 24, fourth control valve; 25, fifth control valve; 26, sixth control valve; 27, feed valve; 28, drain valve; 29, exhaust valve; 30, pressure regulating valve; 31, sampling valve; 32, Y-type filter; 33, thermometer; 34, first pressure gauge; 35, second pressure gauge; 36, first flow meter; 37, second flow meter; 38, liquid level meter. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0023] like Figure 1 As shown, the utility model discloses a ceramic membrane device for nano powder purification, including a cleaning tank 1, a dispersion tank 6 and a ceramic membrane assembly 5. Among them, the cleaning tank 1 adopts a closed stainless steel jacket tank with a heat exchange interlayer 2, and a cooling water inlet 3 connected to the heat exchange interlayer 2 is opened at the bottom of the tank body, and a cooling water outlet 4 connected to the heat exchange interlayer 2 is opened at the top of the tank body. When in use, an external cold source can be connected for temperature control. The cleaning tank 1 is used to place the nano powder slurry to be cleaned, and also serves as a circulation tank. The output end at the bottom of the cleaning tank 1 is connected to a tee, and a sewage pipeline 10 for discharging cleaning wastewater and a feed pipeline 9 for conveying nano powder slurry are connected through the tee. The sewage pipeline 10 is installed with a sewage valve 28 for controlling switching, and the feed pipeline 9 is installed with a feed valve 27 and a feed pump 19 for providing feed power. The output end at the bottom of the cleaning tank 1 is connected to the input end of the ceramic membrane assembly 5 through the feed pipeline 9, and a liquid level meter 38 is arranged in the cleaning tank 1.

[0024] Two groups of ceramic membrane assemblies 5 are arranged in series, and the pore size is set between 10-100nm. One end of the ceramic membrane assembly 5 that outputs the concentrated liquid is connected to a concentrated liquid pipeline 11 that can discharge the concentrated liquid, and the concentrated liquid pipeline 11 is equipped with a first control valve 21 for controlling whether the concentrated liquid is discharged. One end of the ceramic membrane assembly 5 that outputs the dialysate is connected to a dialysate pipeline 17 that can discharge the dialysate, and the dialysate pipeline 17 is equipped with a third control valve 23 for controlling whether the dialysate is discharged; an exhaust pipeline 16 is connected between one end of the ceramic membrane assembly 5 that outputs the concentrated liquid and the concentrated liquid pipeline 11, and the exhaust pipeline 16 is equipped with an exhaust valve 29.

[0025] The dispersion tank 6 also adopts a stainless steel jacket tank with a heat exchange interlayer 2, a cooling water inlet 3, and a cooling water outlet 4. The input end at the top of the dispersion tank 6 is connected to the concentrated liquid pipeline 11 through the first reflux pipeline 12, and the mutually connected position is located between the first control valve and the ceramic membrane assembly 5. The output end at the bottom of the dispersion tank 6 is connected to the top of the cleaning tank 1 through the second reflux pipeline 13. An ultrasonic generator 7 is installed in the dispersion tank 6. When the first control valve 21 is closed, the concentrated liquid can be guided to the dispersion tank 6 through the first reflux pipeline 12 for dispersion treatment, and then the concentrated liquid can be guided to flow back to the cleaning tank 1 through the second reflux pipeline 13 to continue washing.

[0026] The first reflux pipeline 12 is provided with a second control valve 22 for controlling whether the concentrated liquid refluxes. The ultrasonic generator 7, i.e., the ultrasonic disperser, disposed in the dispersion tank 6 can generate ultrasonic waves, and generate mechanical shear force through ultrasonic vibration, so as to quickly mix the nano powder slurry concentrate, break up the nano powder, improve the nano powder regrowth and agglomeration caused by long-term standing and uneven stirring of the nano powder, and ensure the uniformity of the particle size of the nano powder.

[0027] Similar to the concentrate pipeline 11, the dialysate pipeline 17 is connected to a third return pipeline 18, and is connected to the top of the cleaning tank 1 through the third return pipeline 18. The position where the third return pipeline 18 and the dialysate pipeline 17 are connected to each other is located between the third control valve 23 and the ceramic membrane assembly 5. The third return pipeline 18 is provided with a fourth control valve 24 for controlling whether the permeate flows back. By switching the third control valve 23 and the fourth control valve 24, the permeate can be controlled to be discharged or to flow back to the cleaning tank 1 for circulation.

[0028] In addition to the circulation through the first to third reflux pipelines 18, the device is also provided with a circulation pump 20 and an internal circulation pipeline 14. The circulation pump 20 is arranged on the feed pipeline 9 and is located between the feed pump 19 and the ceramic membrane assembly 5. One end of the internal circulation pipeline 14 is connected to the position of the concentrated liquid pipeline 11 near the ceramic membrane assembly 5, and the other end is connected to the feed pipeline 9, and the mutually connected position is located between the feed pump 19 and the circulation pump 20. The circulation pump 20 and the internal circulation pipeline 14 can circulate and purify the nano powder, thereby improving the efficiency of the nano powder purification.

[0029] In addition, in order to slow down the pollution and clogging speed of the ceramic membrane assembly 5, a Y-type filter 32 is provided on the feed pipeline 9, and a fifth control valve 25 and a backwash tank 8 are provided on the dialysate pipeline 17. The Y-type filter 32 is located at the front end of the circulation pipeline and between the feed pump 19 and the circulation pump 20. The Y-type filter 32 can remove a small amount of solid particle impurities contained in the nano powder slurry before it is input into the ceramic membrane assembly 5, thereby protecting the normal operation of the equipment. When cleaning is required, the removed filter cartridge in the Y-type filter 32 can be taken out and reinstalled after treatment, which is convenient for maintenance.

[0030] The backwash tank 8 is located between the fifth control valve 25 and the ceramic membrane assembly 5, and the fifth control valve 25 is located at the front end of the third control valve 23; the backwash tank 8 or the dialysate pipeline 17 is connected to the compressed air pipeline 15 at the part between the backwash tank 8 and the fifth control valve 25, and the compressed air pipeline 15 is provided with a sixth control valve 26 and connected to an air compressor (not shown). In this embodiment, the backwash tank 8 is arranged in a bottom-in-top-out manner, the inlet at the bottom of the backwash tank 8 is connected to the ceramic membrane assembly 5, and the outlet at the top of the backwash tank 8 is provided with a tee and connects the corresponding section of the dialysate pipeline 17 and the compressed air pipeline 15. During the nano-powder purification process, the fifth control valve 25, the sixth control valve 26 and the air compressor can be opened and closed in time with a timer. Compressed air is generated by the air compressor and pumped into the backwash tank 8 through the compressed air pipeline 15. The dialysate stored in the backwash tank 8 is driven by the compressed air to backwash the ceramic membrane assembly 5, thereby slowing down the speed of contamination and clogging of the membrane core in the ceramic membrane assembly 5, ensuring the continuous progress of the nano-powder washing and purification process, and ensuring the efficiency of washing and purification.

[0031] In addition, the feed pipeline 9 is also provided with a temperature gauge 33 and a first pressure gauge 34 for temperature and pressure monitoring, the concentrate pipeline 11 is provided with a second pressure gauge 35, a pressure regulating valve 30 and a first flow meter 36 for pressure and flow monitoring and pressure regulation, and the dialysate pipeline 17 is provided with a second flow meter 37 for flow monitoring. Sampling valves 31 are provided on the concentrate pipeline 11 and the dialysate pipeline 17 for convenient monitoring and inspection.

[0032] The steps for washing and purifying nanopowders using this equipment are as follows:

[0033] S1, purification: after checking that all valves are opened and closed correctly, start the feed pump 19 and the circulation pump 20 in turn, and control the pressure of the purification process to 1 bar to filter 2 liters of nano powder at the ceramic membrane assembly 5. The permeate (membrane permeate waste liquid) produced by the filtration is discharged through the permeate pipeline, and the concentrated liquid (membrane retentate) produced is transported to the dispersion tank 6 through the concentrated liquid pipeline 11 and the first reflux pipeline 12, and is mixed and dispersed by the ultrasonic generator 7. During the treatment, the ultrasonic power is controlled between 10-30KHZ, and after the treatment, it flows back to the cleaning tank 1 through the second reflux pipeline 13.

[0034] S2, washing: when the volume proportion of the permeate is greater than 80%, ultrapure water is continuously added to the cleaning tank 1 for washing to remove as many impurities in the nanopowder as possible;

[0035] S3, backwashing: During the purification process, the fifth control valve 25 is closed periodically in conjunction with the timer, and the sixth control valve 26 and the air compressor are opened to introduce compressed air into the backwash tank 8 to backwash the permeate temporarily stored in the backwash tank back to the ceramic membrane assembly 5, thereby backwashing the ceramic membrane assembly 5. During the backwashing process, the feed pump 19 and the circulation pump 20 automatically stop running.

[0036] By adopting the method of ultrasonic dispersion and ultrapure water washing, after adding 15 times the volume of the raw material to purify and filter the raw material, the impurity content in the nano powder concentrate and the permeate is sampled and detected through the sampling valve 31. The impurity content in the concentrated liquid sample is reduced from 10.7% of the impurity content in the initial raw material to 0.021%. After the concentrated liquid is dried, the nano powder is obtained for thermogravimetric analysis. After testing, the content of organic matter in the obtained nano powder is reduced from the initial 24.6% to 0.08%, indicating that the nano powder is well purified, no agglomeration occurs during the purification process, and the amount of water used for washing is saved.

[0037] Although the present invention has been specifically demonstrated and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes in form and details of the present invention are within the scope of protection of the present invention without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A ceramic membrane device for purifying nanopowders, characterized in that: Including cleaning tank, dispersion tank and ceramic membrane assembly; The output end of the cleaning tank is connected to the input end of the ceramic membrane assembly through a feed pipeline, and a feed pump is provided on the feed pipeline; One end of the ceramic membrane assembly outputting concentrated liquid is connected to a concentrated liquid pipeline, and one end outputting dialysate is connected to a dialysate pipeline, and a first control valve is provided on the concentrated liquid pipeline; The input end of the dispersion tank is connected to the concentrated liquid pipeline through a first reflux pipeline, and the interconnected position is located between the first control valve and the ceramic membrane assembly. The output end of the dispersion tank is connected to the cleaning tank through a second reflux pipeline; a second control valve is provided on the first reflux pipeline, and an ultrasonic generating device is provided in the dispersion tank.

2. A ceramic membrane device for purifying nanopowders according to claim 1, characterized in that: It also includes a circulation pump and an internal circulation pipeline. The circulation pump is arranged on the feed pipeline and is located between the feed pump and the ceramic membrane assembly. One end of the internal circulation pipeline is connected to the concentrated liquid pipeline, and the other end is connected to the feed pipeline. The mutually connected position is located between the feed pump and the circulation pump.

3. A ceramic membrane device for purifying nanopowders as claimed in claim 1, characterized in that: It also includes a Y-type filter, which is arranged on the material delivery pipeline.

4. A ceramic membrane device for purifying nanopowders as claimed in claim 1, characterized in that: A third control valve is arranged on the dialysate pipeline, and is connected to the cleaning tank via a third return pipeline. The position where the third return pipeline and the dialysate pipeline are connected to each other is located between the third control valve and the ceramic membrane assembly. A fourth control valve is arranged on the third return pipeline.

5. The ceramic membrane device for purifying nanopowders according to claim 1, characterized in that: A fifth control valve and a backwash tank are provided on the dialysate pipeline, and the backwash tank is located between the fifth control valve and the ceramic membrane assembly. The backwash tank or the dialysate pipeline is connected to a compressed air pipeline at a portion between the backwash tank and the fifth control valve. A sixth control valve is provided on the compressed air pipeline and is connected to an air compressor.

6. A ceramic membrane device for purifying nanopowders as claimed in claim 1, characterized in that: An exhaust pipeline is connected between one end of the ceramic membrane assembly that outputs the concentrated liquid and the concentrated liquid pipeline, and an exhaust valve is arranged on the exhaust pipeline.

7. The ceramic membrane device for purifying nanopowders according to claim 1, characterized in that: A sewage discharge pipeline is connected to the bottom of the cleaning tank, and a sewage discharge valve is arranged on the sewage discharge pipeline.

8. The ceramic membrane device for purifying nanopowders according to claim 1, characterized in that: The material delivery pipeline is provided with a temperature gauge and a first pressure gauge, the concentrate pipeline is provided with a second pressure gauge, a pressure regulating valve and a first flow meter, and the dialysate pipeline is provided with a second flow meter.

9. The ceramic membrane device for purifying nanopowders according to claim 1, characterized in that: Sampling valves are provided on the concentrate pipeline and the dialysate pipeline.

10. The ceramic membrane device for purifying nanopowders according to claim 1, characterized in that: The ceramic membrane components are arranged in two groups in series.

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