CN112266243A - Method and device for washing superfine powder material for ceramic capacitor - Google Patents
Method and device for washing superfine powder material for ceramic capacitor Download PDFInfo
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- CN112266243A CN112266243A CN202011473588.4A CN202011473588A CN112266243A CN 112266243 A CN112266243 A CN 112266243A CN 202011473588 A CN202011473588 A CN 202011473588A CN 112266243 A CN112266243 A CN 112266243A
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- 238000005406 washing Methods 0.000 title claims abstract description 79
- 239000000463 material Substances 0.000 title claims abstract description 72
- 239000000843 powder Substances 0.000 title claims abstract description 67
- 239000003985 ceramic capacitor Substances 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000003860 storage Methods 0.000 claims abstract description 67
- 238000001914 filtration Methods 0.000 claims abstract description 54
- 239000002994 raw material Substances 0.000 claims abstract description 29
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 27
- 239000002002 slurry Substances 0.000 claims abstract description 24
- 239000012535 impurity Substances 0.000 claims abstract description 13
- 238000005086 pumping Methods 0.000 claims abstract description 9
- 239000000706 filtrate Substances 0.000 claims abstract description 7
- 239000013049 sediment Substances 0.000 claims abstract description 7
- 239000008394 flocculating agent Substances 0.000 claims abstract description 4
- 238000003825 pressing Methods 0.000 claims abstract description 4
- 239000007788 liquid Substances 0.000 claims description 22
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 claims description 14
- 229910002113 barium titanate Inorganic materials 0.000 claims description 14
- 239000006228 supernatant Substances 0.000 claims description 12
- 239000012498 ultrapure water Substances 0.000 claims description 12
- 238000004062 sedimentation Methods 0.000 claims description 11
- 239000011521 glass Substances 0.000 claims description 5
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 claims description 4
- 239000011858 nanopowder Substances 0.000 claims description 4
- 239000011449 brick Substances 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 3
- SPAGIJMPHSUYSE-UHFFFAOYSA-N Magnesium peroxide Chemical compound [Mg+2].[O-][O-] SPAGIJMPHSUYSE-UHFFFAOYSA-N 0.000 claims description 2
- AYJRCSIUFZENHW-DEQYMQKBSA-L barium(2+);oxomethanediolate Chemical compound [Ba+2].[O-][14C]([O-])=O AYJRCSIUFZENHW-DEQYMQKBSA-L 0.000 claims description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 2
- 238000005189 flocculation Methods 0.000 claims description 2
- 230000016615 flocculation Effects 0.000 claims description 2
- SOQBVABWOPYFQZ-UHFFFAOYSA-N oxygen(2-);titanium(4+) Chemical compound [O-2].[O-2].[Ti+4] SOQBVABWOPYFQZ-UHFFFAOYSA-N 0.000 claims description 2
- 235000012239 silicon dioxide Nutrition 0.000 claims description 2
- 239000000377 silicon dioxide Substances 0.000 claims description 2
- 238000011085 pressure filtration Methods 0.000 claims 1
- 230000008901 benefit Effects 0.000 abstract description 5
- 239000002270 dispersing agent Substances 0.000 abstract description 5
- 238000009776 industrial production Methods 0.000 abstract description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 18
- 239000000919 ceramic Substances 0.000 description 9
- 238000004519 manufacturing process Methods 0.000 description 9
- 239000004408 titanium dioxide Substances 0.000 description 9
- 239000004743 Polypropylene Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 239000002245 particle Substances 0.000 description 5
- 238000000926 separation method Methods 0.000 description 5
- 229910000975 Carbon steel Inorganic materials 0.000 description 4
- 239000010962 carbon steel Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000004698 Polyethylene Substances 0.000 description 3
- 229910010293 ceramic material Inorganic materials 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 239000002105 nanoparticle Substances 0.000 description 3
- -1 polypropylene Polymers 0.000 description 3
- 229920001155 polypropylene Polymers 0.000 description 3
- 239000004810 polytetrafluoroethylene Substances 0.000 description 3
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 2
- 239000004744 fabric Substances 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical class [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 229910001420 alkaline earth metal ion Inorganic materials 0.000 description 1
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000011267 electrode slurry Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 230000005476 size effect Effects 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/46—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates
- C04B35/462—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates
- C04B35/465—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates based on alkaline earth metal titanates
- C04B35/468—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates based on alkaline earth metal titanates based on barium titanates
- C04B35/4682—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates based on alkaline earth metal titanates based on barium titanates based on BaTiO3 perovskite phase
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D36/00—Filter circuits or combinations of filters with other separating devices
- B01D36/04—Combinations of filters with settling tanks
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
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Abstract
The invention relates to a device and a method for washing superfine powder materials for ceramic capacitors, which are characterized in that: (1) adding the superfine powder material into a pre-washing storage tank (1), adding high pure water, and circulating the material in the tank body to prepare 10-50% washing slurry; (2) pumping the slurry into a filtering device (4), controlling the pressure to be 0.1-2.0MPa, and enabling the filtrate to enter a collecting storage tank (3); (3) the collecting storage tank is kept stand for layering, and the lower-layer superfine sediment is pumped into the filtering device (4) again; (4) adding high pure water into the raw material storage tank (1), and pumping the raw material into a filtering device (4) for filter pressing and washing until the total impurity content in the filtrate at the outlet of the filtering device is less than 500 ppm; (5) and (3) carrying out pressure maintaining concentration on the superfine powder material in the filtering device (4), and controlling the water content to be 10-30%. The invention has the advantages that: the method has the advantages of low equipment investment cost, simple operation, no addition of dispersing agent and flocculating agent, high yield, good universality in the aspect of washing the superfine powder material for the ceramic capacitor and suitability for industrial production.
Description
Technical Field
The invention belongs to the field of preparation of dielectric nano ceramic materials, and relates to a method and a device for washing an ultrafine powder material for a ceramic capacitor.
Technical Field
The superfine powder material for the ceramic capacitor mainly comprises important parts such as superfine functional ceramic powder material, electrode slurry and the like; the superfine functional ceramic powder material occupies the main production and manufacturing cost and directly influences the manufacturing process and application effect of the ceramic capacitor.
With the development of ceramic capacitors, especially chip multilayer ceramic capacitors, toward miniaturization and high capacitance ratio. The requirements for developing dielectric ceramic superfine powder materials are becoming more and more demanding. The dielectric ceramic material for the ceramic capacitor is required to be characterized by easy production, low cost, good stability, easy industrialization and the like.
At present, ceramic electrodes are preparedThe dielectric ceramic superfine powder material for the container is AB3The structure of O perovskite titanate series is a main framework, and particularly barium titanate functional ceramic materials are used as the preferred main materials for the chip type multilayer ceramic capacitor. In the preparation process, barium titanate base (main ceramic powder material) as a main component and formula base (rare earth metal and alkaline earth metal oxide or carbonate) as an auxiliary component are subjected to solid-liquid mixing and separation to remove metal ions doped in the powder material, and after solid-liquid separation and impurity removal, the powder is stirred or ground to be uniformly dispersed, and then dried and formed to obtain the dielectric ceramic ultrafine powder for the ceramic capacitor.
If the barium titanate-based raw powder is not washed, unknown alkaline earth metal ions, such as sodium, potassium and other metal elements, are contained in the barium titanate base, accurate and effective formula calculation is difficult to perform in the formula due to the existence of the ions, and the dielectric property, loss and volume value change rate of the prepared perovskite salt are seriously influenced due to the introduction of impurities; therefore, it is necessary to remove a trace amount of metal ion elements by washing.
In the prior art, a technology and a management mode for improving the purity of raw materials and controlling metal equipment in a non-contact mode are mostly adopted, but the product cost is easily increased, and meanwhile, impurities are difficult to avoid being introduced or brought in the production and manufacturing process due to the fact that the control level is different. In addition, a mode of adding a flocculating agent or a dispersing agent is adopted to flocculate the nano-scale particles and then carry out solid-liquid separation, but in such a mode, impurity ions can be inevitably introduced, so that the problem of agglomeration of the flocculated powder slurry in the drying process is solved, the application performance of the functional ceramic powder is further influenced, and the functional ceramic powder has no excellent competitive advantage.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides a method and a device for washing an ultrafine powder material for a ceramic capacitor; the device and the method can effectively solve the problems of difficult solid-liquid separation, low separation efficiency and environmental pollution caused by a large amount of superfine powder contained in the separated water in the washing process.
In order to achieve the purpose, the invention adopts the following technical scheme:
a washing device of superfine powder materials for ceramic capacitors is characterized by comprising the following devices:
the bottom of the pre-washing raw material storage tank is connected with an inlet of a filtering device through a pipeline, an outlet of the filtering device is connected with a collecting storage tank through a pipeline, an outlet at the bottom of the collecting storage tank is connected with the bottom of the pre-washing raw material storage tank through a pipeline, and an outlet at the middle part of the collecting storage tank is connected with an inlet at the middle part of the pre-washing raw material storage tank through a pipeline; wherein the bottom of the pre-washing raw material storage tank is connected to the top inlet of the pre-washing raw material storage tank through a pipeline and a pump, and a pipeline arranged at the middle outlet of the collecting storage tank is connected to the sedimentation tank.
Further, a liquid level meter is arranged on the collecting storage tank.
Furthermore, the filtering device is a belt filter press or a cantilever beam filter press, and the diaphragm is used for draining water under water pressure or air pressure.
Further, the pressure of the filtering device is 0.1-2.0MPa, and the filtering area is 30-1000m2The filter cloth is made of monofilament polypropylene fiber and has air permeability of 20-100L/m2•s。
Furthermore, each pipeline is provided with a corresponding delivery pump and a corresponding control valve, wherein the delivery pump is a positive displacement pump, a jet pump or an impeller pump.
Further, the raw material storage tank and the collecting storage tank are made of stainless steel 316S or carbon steel, the linings are made of PTFE, PE, PP and PO, and the thickness of the lining material is 1-40 mm.
Furthermore, the liquid level meter is a side-mounted magnetic turning plate, a double-flange threaded glass tube or a double-flange glass tube structure.
Furthermore, the material of the liquid level meter pipeline is stainless steel 316L, PP, glass, PE or PTFE and the like, and the pipe diameter of the liquid level meter is 20-80 mm.
Furthermore, the pipeline is made of stainless steel 316S or carbon steel, the lining of the pipeline is made of PTFE, PE or PP and the like, and the thickness of the lining material is 1-20 mm.
A method for washing superfine powder material for ceramic capacitor is characterized by comprising the following steps:
(1) adding the superfine powder material for the ceramic capacitor into a pre-washing storage tank, adding high-purity water, circulating the material in the tank body through a pipeline and a delivery pump at the bottom of the pre-washing storage tank (20-60 min each time), and fully and uniformly mixing the superfine powder material and the pure water to prepare washing slurry with the concentration of 10-50%;
(2) pumping the washing slurry prepared in the step into a filtering device through a pipeline, controlling the internal pressure of the filtering device to be 0.1-2.0MPa, and enabling filtrate (water and a small amount of superfine slurry) discharged from the filtering device to enter a collecting storage tank through the pipeline;
(3) after the filtration is finished, the collection storage tank is kept stand (the liquid level height and the layering effect are displayed through a liquid level meter), supernatant and lower-layer superfine sediment are formed after layering, the supernatant is conveyed into a sedimentation tank, and the lower-layer superfine sediment is pumped into a filtering device again through a pipeline and a conveying pump for filtration;
(4) adding high-purity water into a raw material storage tank, pumping the raw material storage tank into a filtering device through a pipeline and a delivery pump, and performing filter pressing washing and filtering impurity removal (removing trace impurity elements dissolved in pure water in slurry of the raw material storage tank) until the total impurity content in filtrate at the outlet of the filtering device is less than 500 ppm;
(5) and (3) concentrating the superfine powder material in the filtering device under the pressure of 0.1-2.0MPa, and controlling the water content to be 10-30% to obtain the washed superfine nano powder material for the ceramic capacitor.
Further, the superfine powder materials for the ceramic capacitors are added into a pre-washing storage tank in 3-10 batches, and the concentration error range of the superfine powder material slurry for each batch of the ceramic capacitors is controlled within +/-5 percent.
And further, carrying out flocculation precipitation on the washing water in the sedimentation tank, and then carrying out filter pressing and concentration on the washing water to obtain a raw material of the baked brick, wherein the flocculating agent is PAC, PAM, SPFS or PAFC and the like.
Further, the ultrafine powder material for the ceramic capacitor in the step (1) is nano barium titanate, nano titanium dioxide, nano magnesium dioxide, manganese oxide, barium carbonate, calcium carbonate, silicon dioxide and other materials.
In the process of washing the nanometer-level superfine electronic functional powder material, because of the size effect of the nanometer particles, the solution of the nanometer particles is easy to overflow when being washed and is difficult to collect, or the loss of the tiny nanometer particles is caused, so that the product waste or the environment pollution is caused. The device and the method not only solve the problem of removing impurity ions to purify functional powder materials, but also solve the problem of no need of any substances such as an introduced dispersant and the like, can realize the effect of no pollution, can recover and wash the extremely small nano particles penetrating through the filtering device again to improve the yield, not only ensures the purity, but also realizes the industrialized large-scale function.
The invention has the advantages that:
1. the method has the advantages of low equipment investment cost, simple operation, no need of adding a dispersant and a flocculant, no damage to the structure of powder material particles, high washing and collecting efficiency, high yield of over 99.8 percent, and concrete embodiment in the following aspects:
(1) and (3) environmental protection: the invention uses high-purity water, does not add any macromolecular organic dispersant or other auxiliary agents, and the washing clean water is precipitated in a sedimentation tank to be processed into a raw material of the baked brick without discharging waste water and sewage;
(2) the cost is low: the device adopts the tank body, the valve, the pump and other equipment which are conventional production equipment convenient to obtain, has low manufacturing cost and is easy for industrial production;
(3) the yield is high: the ultrafine nanoparticles penetrating through the filtering device can be collected, and no product waste is caused;
(4) the purity is high: no damage to the particles (see fig. 2 and fig. 3), high product purity (see table 1);
2. the method of the invention has good universality in the aspect of washing the superfine powder material for the ceramic capacitor, and is particularly suitable for industrialized production.
Drawings
FIG. 1 is a schematic view of an apparatus for washing an ultrafine powder material for a ceramic capacitor;
FIG. 2 is an electron microscope image of the barium titanate ultrafine powder material after washing;
FIG. 3 is an electron microscope image of the titanium dioxide ultrafine powder material after washing.
Detailed Description
The invention is further illustrated with reference to fig. 1:
a washing device for washing superfine powder materials for ceramic capacitors comprises the following equipment:
the bottom of the pre-washing raw material storage tank 1 is connected with the inlet of the filtering device 4 through a pipeline 17 and a control valve 10, a delivery pump 8, a control valve 11 and a control valve 14 on the pipeline, the outlet of the filtering device 4 is connected with the collection storage tank 3 through a pipeline 18, and the outlet of the bottom of the collection storage tank 3 is connected with the pipeline between the delivery pump 8 and the control valve 11 through a pipeline 21 and a control valve 15 and a delivery pump 22 on the pipeline; the middle outlet of the collecting storage tank 3 is connected with the middle inlet of the pre-washing raw material storage tank 1 through a pipeline 19, a control valve 16 on the pipeline, a delivery pump 9 and a control valve 12;
wherein, a branch pipeline 20 is arranged on the pipeline between the control valve 11 and the control valve 14 and is connected to the top inlet of the pre-washing raw material storage tank 1, and the pipeline 20 is provided with a control valve 13; a branch pipeline is arranged on the pipeline between the delivery pump 9 and the control valve 12 and connected to the sedimentation tank 24, and a control valve 23 is arranged on the branch pipeline;
a liquid level meter 7 is arranged on the collecting storage tank 3, the liquid level meter 7 is of a side-mounted magnetic flip structure, a pipeline of the liquid level meter is made of stainless steel 316L, and the pipe diameter is 30 mm;
the filter device 4 is a belt filter press, the diaphragm is used for draining water under the air pressure of 0.1-2.0MPa, and the filtering area is 30-1000m2The filter cloth is made of monofilament polypropylene fiber and has air permeability of 20-100L/m2•s；
The pipeline is made of carbon steel, the lining of the pipeline is made of PP (polypropylene), the thickness of the lining material is 10mm, and the delivery pump is a positive displacement pump, a jet pump or an impeller pump;
the raw material storage tank 1 and the collection storage tank 3 are made of carbon steel, the lining of the raw material storage tank and the collection storage tank is made of PO, and the thickness of the lining is 20 mm.
A washing method for washing superfine powder materials for ceramic capacitors comprises the following specific implementation steps:
example 1
1. Adding a barium titanate ultrafine powder material for a ceramic capacitor into a pre-washing storage tank 1, adding high-purity water, opening valves 10, 11 and 13, closing all other valves, opening a circulating pump 8, circulating for 2 times, and circulating for 20 minutes each time to fully and uniformly mix the barium titanate ultrafine powder material with the high-purity water to prepare washing slurry with the concentration of 15%;
2. after the raw materials are circularly and uniformly dispersed in the pre-washing storage tank 1, opening a valve 14, sequentially closing valves 15 and 16 and a valve 13, pumping washing slurry into the filtering device 4 through a pipeline 17 by a pump 8, controlling the internal pressure of the filtering device to be 0.3MPa, and allowing filtered filtrate to enter the collecting storage tank 3 through a pipeline 18;
3. continuously feeding the washing slurry into the filtering device 4 until the washing slurry completely enters the filtering device 4, stopping feeding, and closing the conveying pump 8 and the valve 10;
4. collecting the superfine slurry leaked from the filtering device 4 in the storage tank 3, standing for 80min, and layering to form superfine precipitate 6 and supernatant 5 (the liquid level height and layering effect are displayed by a liquid level meter 7);
5. opening valves 16 and 23, closing valve 12, conveying the supernatant 5 to a sedimentation tank 24 through a conveying pump 9, opening valve 12 and closing valve 23 when the impurity content of the supernatant 5 is less than 500ppm through a washing test, and conveying the supernatant 5 to a washing storage tank 1 for recycling;
6. the valves 12 and 16 are closed, the valves 11, 14 and 15 are opened, the superfine sediment 6 is conveyed into the filtering device 4 again through the pump 22, and filtered water flows into the collecting storage tank 3 through the pipeline 18;
7. adding high-purity water into the raw material storage tank 1, closing the valves 12 and 13, opening the valves 10, 11 and 14, and pumping the high-purity water flow through the filtering device 4 by the pump 8 until the outlet water of the filtering device is clear;
8. and (3) performing pressure maintaining concentration (0.65 MPa for 20 min) on the barium titanate superfine powder material in the filtering device 4, and controlling the water content to be 20% to obtain the washed barium titanate superfine nano powder material (the content is 99.82%) for the ceramic capacitor.
Example 2
According to the steps 1-8 of the example 1, the barium titanate ultrafine powder material for the ceramic capacitor is dispersed in the prewashing storage tank 1 in 3 batches, the concentration error range of the barium titanate ultrafine powder slurry for each batch of the ceramic capacitor is controlled within +/-5%, and the content of the barium titanate ultrafine nano powder material for the ceramic capacitor after washing is 99.89%.
Example 3
1. Adding titanium dioxide superfine powder materials for ceramic capacitors into a pre-washing storage tank 1, adding high-purity water, opening valves 10, 11 and 13, closing all other valves, opening a circulating pump 8, circulating for 3 times, and circulating for 30 minutes each time to fully and uniformly mix the titanium dioxide superfine powder materials with the high-purity water to prepare washing slurry with the concentration of 25%;
2. after the slurry is circularly and uniformly dispersed in the storage tank 1, opening a valve 14, sequentially closing valves 15 and 16 and a valve 13, pumping the slurry 2 to be washed into the filtering device 4 through a pipeline 17 by a pump 8, controlling the internal pressure of the filtering device to be 0.3MPa, and feeding the filtered water into the collecting storage tank 3 through a pipeline 18;
3. continuously feeding the washing slurry into the filtering device 4 until the washing slurry completely enters the filtering device 4, stopping feeding, and closing the conveying pump 8 and the valve 10;
4. collecting the superfine slurry leaked from the filtering device 4 in the storage tank 3, standing for 60min, layering to form superfine precipitate 6 and supernatant 5, and displaying the liquid level height and layering effect by a liquid level meter 7;
5. opening valves 16 and 23, closing valve 12, conveying the supernatant 5 to a sedimentation tank 24 through a conveying pump 9, opening valve 12 and closing valve 23 when the impurity content of the supernatant 5 is less than 400ppm through a washing test, and conveying the supernatant 5 to a washing storage tank 1 for recycling;
6. the valves 12 and 16 are closed, the valves 11, 14 and 15 are opened, the superfine sediment 6 is conveyed into the filtering device 4 again through the pump 22, and filtered water flows into the collecting storage tank 3 through the pipeline 18;
7. adding high-purity water into the raw material storage tank 1, closing the valves 12 and 13, opening the valves 10, 8 and 14, and enabling the pure water to flow through the filtering device 4 through the pump 8 until washing outlet water is clear;
8. the titanium dioxide ultrafine powder material in the filter device 4 is concentrated under the pressure maintaining condition (0.5 Pa and 10 min), the water content is controlled to be 25%, and the washed titanium dioxide ultrafine powder material (the content is 99.93%) for the ceramic capacitor can be obtained.
Example 4
According to the steps 1-8 of the example 1, the titanium dioxide ultrafine powder material for the ceramic capacitor is dispersed in the prewashing storage tank 1 for 4 times in batches, the concentration error range of the titanium dioxide ultrafine powder slurry for each batch of the ceramic capacitor is controlled within +/-5%, and the content of the washed titanium dioxide ultrafine powder material for the ceramic capacitor is 99.90%.
The results of comparing the effects before and after washing with titanium dioxide are shown in Table 1 below:
TABLE 1
Unless otherwise indicated, when the present invention relates to percentages between liquids, said percentages are volume/volume percentages; the invention relates to the percentage between liquid and solid, said percentage being volume/weight percentage; the invention relates to the percentages between solid and liquid, said percentages being weight/volume percentages; the balance being weight/weight percent.
Although the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended to cover in the appended claims all such modifications, equivalents, and improvements that fall within the true spirit and scope of the invention.
Claims (10)
1. A washing device of superfine powder materials for ceramic capacitors is characterized by comprising the following devices:
the bottom of the pre-washing raw material storage tank (1) is connected with an inlet of a filtering device (4) through a pipeline, an outlet of the filtering device (4) is connected with a collecting storage tank (3) through a pipeline, an outlet at the bottom of the collecting storage tank (3) is connected with the bottom of the pre-washing raw material storage tank (1) through a pipeline, and an outlet at the middle part of the collecting storage tank (3) is connected with an inlet at the middle part of the pre-washing raw material storage tank (1) through a pipeline; wherein the bottom of the pre-washing raw material storage tank (1) is connected to the top inlet of the pre-washing raw material storage tank (1) through a pipeline and a pump, and a branch is arranged on the pipeline of the middle outlet of the collection storage tank (3) and is connected to the sedimentation tank (24).
2. The apparatus for washing ultrafine powder material for ceramic capacitor as set forth in claim 1, wherein: and a liquid level meter (7) is arranged on the collecting storage tank (3).
3. The apparatus for washing ultrafine powder material for ceramic capacitor as set forth in claim 1, wherein: the filtering device (4) is a belt filter press or a cantilever beam filter press, and the diaphragm is used for draining water under water pressure or air pressure.
4. The apparatus for washing ultrafine powder material for ceramic capacitors as defined in claim 2, wherein: the liquid level meter (7) is a side-mounted magnetic turning plate, a double-flange threaded glass pipe or a double-flange glass pipe structure.
5. A method for washing superfine powder material for ceramic capacitor is characterized by comprising the following steps:
(1) adding the superfine powder material for the ceramic capacitor into a pre-washing storage tank (1), adding high-purity water, circulating the material in a tank body through a pipeline and a delivery pump at the bottom of the pre-washing storage tank (1), and fully and uniformly mixing the superfine powder material and the pure water to prepare washing slurry with the concentration of 10-50%;
(2) pumping the washing slurry prepared in the step (1) into a filtering device (4) through a pipeline, controlling the internal pressure of the filtering device to be 0.1-2.0MPa, and enabling filtrate from the filtering device (4) to enter a collecting storage tank (3) through the pipeline;
(3) after the filtration is finished, the collection storage tank (3) is kept stand, the supernatant and the lower-layer superfine sediment are formed after layering, the supernatant is conveyed into a sedimentation tank (24), and the lower-layer superfine sediment is pumped into the filtration device (4) again through a pipeline and a conveying pump for filtration;
(4) adding high-purity water into a raw material storage tank (1), pumping into a filtering device (4) through a pipeline and a delivery pump, and performing filter pressing washing and filtering impurity removal until the total impurity content in the filtrate at the outlet of the filtering device is less than 500 ppm;
(5) and (3) carrying out pressure maintaining concentration on the superfine powder material in the filtering device (4), and controlling the water content to be 10-30% to obtain the washed superfine nano powder material for the ceramic capacitor.
6. The method for washing the ultrafine powder material for ceramic capacitors as claimed in claim 5, wherein: the ceramic capacitor ultrafine powder materials are added into a pre-washing storage tank (1) in 3-10 batches, and the concentration error range of each batch of ceramic capacitor ultrafine powder material slurry is controlled within +/-5%.
7. The method for washing the ultrafine powder material for ceramic capacitors as claimed in claim 5, wherein: and washing water in the sedimentation tank (24) is subjected to flocculation sedimentation and then is subjected to pressure filtration and concentration to obtain a raw material of the baked brick, wherein the flocculating agent is PAC, PAM, SPFS or PAFC.
8. The method for washing the ultrafine powder material for ceramic capacitors as claimed in claim 5, wherein: and (2) in the step (1), the circulation time of each time in the tank body is 20-60 min.
9. The method for washing the ultrafine powder material for ceramic capacitors as claimed in claim 5, wherein: the pressure of the pressure maintaining concentration operation in the step (5) is 0.1-2.0 MPa.
10. The method for washing the ultrafine powder material for ceramic capacitors as claimed in any one of claims 5 to 9, wherein: the superfine powder material for the ceramic capacitor in the step (1) is nano barium titanate, nano titanium dioxide, nano magnesium dioxide, manganese oxide, barium carbonate, calcium carbonate and silicon dioxide material.
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