阅读说明：本技术 一种超细粉体气相分级设备 (Superfine powder gas-phase classification equipment ) 是由 刘晓宁 蔡建亮 周庆祺 陈昊 王海峰 于 2020-12-03 设计创作，主要内容包括：本发明公开了一种超细粉体气相分级设备,涉及粉体分级技术领域,其技术方案要点包括设置有上端进口、侧面进风口以及下端出口的分散器,所述分散器的上端进口连接有进料机,所述分散器的侧面进风口连通有送风机,所述分散器的下端出口连接有分级机；所述分级机的下端出料口连接有收集罐；所述分级机内设置有细粉出粉管,所述细粉出粉管的下端从所述分级机的下端穿出,且穿出的一端连接有反吹罐；所述收集罐的顶端连接有第一引风机,所述反吹罐的顶端连接有第二引风机,所述第一引风机和所述第二引风机的出风口相互连通,并与所述送风机和所述分级机连通。本发明具有有效解决粉体颗粒粒径分布不均匀、分级精度和分级效率较低等问题的效果。(The invention discloses gas phase grading equipment for ultrafine powder, which relates to the technical field of powder grading, and adopts the technical scheme that the gas phase grading equipment comprises a disperser provided with an upper end inlet, a side surface air inlet and a lower end outlet, wherein the upper end inlet of the disperser is connected with a feeder, the side surface air inlet of the disperser is communicated with a blower, and the lower end outlet of the disperser is connected with a grader; a discharge port at the lower end of the classifier is connected with a collecting tank; a fine powder outlet pipe is arranged in the classifier, the lower end of the fine powder outlet pipe penetrates out of the lower end of the classifier, and the penetrating end of the fine powder outlet pipe is connected with a back flushing tank; the top of holding vessel is connected with first draught fan, the top of blowback jar is connected with the second draught fan, first draught fan with the air outlet of second draught fan communicates each other, and with the forced draught blower with the grader intercommunication. The invention has the effect of effectively solving the problems of uneven particle size distribution, low grading precision and grading efficiency and the like of powder particles.)

1. A superfine powder gas-phase classification equipment is characterized in that: the device comprises a disperser (2) provided with an upper end inlet, a side air inlet and a lower end outlet, wherein the upper end inlet of the disperser (2) is connected with a feeder (1), the side air inlet of the disperser (2) is communicated with a blower (3), and the lower end outlet of the disperser (2) is connected with a classifier (4); a discharge hole at the lower end of the classifier (4) is connected with a collecting tank (6); a fine powder outlet pipe (43) is arranged in the classifier (4), the lower end of the fine powder outlet pipe (43) penetrates out of the lower end of the classifier (4), and the penetrating end is connected with a back flushing tank (8); the top of holding vessel (6) is connected with first draught fan (101), the top of blowback jar (8) is connected with second draught fan (102), first draught fan (101) with the air outlet of second draught fan (102) communicates each other, and with forced draught blower (3) with grader (4) intercommunication.

2. The gas phase classification apparatus for ultrafine powder according to claim 1, wherein: grader (4) are including separating chamber (41), the conical coarse powder room (42) and the connection that are the back taper porous flange (5) of separating chamber (41) and coarse powder room (42), the top feed inlet of separating chamber (41) with disperser (2) are connected, the lower extreme discharge gate of coarse powder room (42) is connected with holding vessel (6), porous flange (5) with first draught fan (101) with the air outlet intercommunication of second draught fan (102).

3. The gas phase classification apparatus for ultrafine powder according to claim 2, wherein: the porous flange (5) is provided with a plurality of air inlets (51), and the air inlets (51) are arranged along the circumferential direction at equal radian.

4. The gas phase classification apparatus for ultrafine powder according to claim 3, wherein: the number of the air inlet holes (51) is 12, and the aperture is 10 mm.

5. The gas phase classification apparatus for ultrafine powder according to claim 2, wherein: the outside of porous flange (5) is provided with and is used for sealed induced air cover (44), first draught fan (101) with the air outlet of second draught fan (102) with the inboard intercommunication of induced air cover (44).

6. The gas phase classification apparatus for ultrafine powder according to claim 2, wherein: air outlets of the first induced draft fan (101) and the second induced draft fan (102) are provided with an emptying pipeline (103); and vacuum pressure gauges are arranged at the bottom discharge ports of the fine powder outlet pipe (43) and the coarse powder chamber (42).

7. The gas phase classification apparatus for ultrafine powder according to claim 2, wherein: disperser (2) include with feeder hopper (21) that feeder (1) is connected and set up dispersion awl (22) of the discharge end lower extreme of feeder hopper (21), the lower extreme of dispersion awl (22) is provided with deflector (23) that are the back taper, the upper end setting of fine powder play powder pipe (43) is in the lower extreme of deflector (23).

8. The gas phase classification apparatus for ultrafine powder according to claim 7, wherein: the discharge end of the feed hopper (21), the axis of the dispersion cone (22) and the guide disc (23) coincide with the axis of the separation chamber (41).

9. The gas phase classification apparatus for ultrafine powder according to claim 1, wherein: first draught fan (101) with the air outlet of second draught fan (102) has connected gradually heat exchanger (11) and dust remover (12), the air outlet of dust remover (12) with grader (4) with forced draught blower (3) communicate respectively, and the air outlet of dust remover (12) with be provided with nitrogen gas source (13) between forced draught blower (3).

10. The gas phase classification apparatus for ultrafine powder according to claim 1, wherein: the bottom of the collecting tank (6) is provided with a bottom flow tank (7); an overflow tank (9) is arranged at the bottom of the back flushing tank (8); the feeder (1) is a vibration blanking machine.

Technical Field

The invention relates to the technical field of powder classification, in particular to gas-phase classification equipment for ultrafine powder.

Background

The ultrafine powder generally refers to powder with a particle size of not more than 10 μm, wherein powder with a particle size of 0.1-1 μm is called submicron powder, and powder with a particle size of 1-100 nm is called nano powder. The ultrafine powder is classified according to the type of material, and includes various types such as metal, nonmetal, organic, inorganic, and biological. Classification is one of the conventional means for obtaining high-quality powder materials of different specifications in the field of material manufacturing, and since different types of ultrafine powders have different characteristics, technicians often use different classification force fields to effectively classify the ultrafine powders, such as gravity field classification, centrifugal force field classification, inertial force field classification, electric field force classification, magnetic field force classification, thermal gradient force field classification, and chromatography classification, so as to relatively efficiently obtain the ultrafine powder materials of different particle size distributions. The classification methods commonly used include liquid phase classification and gas phase classification, or wet classification and dry classification. The liquid phase classification has the advantages that a product with fine particle size can be obtained, the particle size distribution range of the powder can be controlled in a narrow range, the potential safety hazard of absolute ethyl alcohol in a common liquid phase classification medium is high, water is easy to corrode or oxidize powder materials, the general process of the liquid phase classification is relatively complex, and the production cost is high. Compared with liquid-phase classification, gas-phase classification has the advantages of saving post-treatment processes such as drying, redispersion and the like, along with relatively low production cost and simple process.

In the prior art, a cyclone classifier is generally adopted as a classifying device, and the cyclone classifier is simple in structure, high in operation elasticity, convenient to maintain, low in price and widely applied to industrial production. The cyclone classifier has the working principle that the airflow is used as a carrier to drive powder to enter a cyclone body tangentially and form vortex motion, powder particles are simultaneously acted by centrifugal force and gravity, coarse powder particles with larger mass move downwards along with outer ring flow after contacting the inner wall of the cyclone body and enter an underflow collecting barrel, fine powder particles with smaller mass move upwards along with the inner ring flow in the center of the cyclone body and enter an overflow collector, and the purpose of classification is achieved.

However, since the conventional cyclone classifier only has a tangential single air inlet, after powder enters the cyclone body under the drive of air flow, the rotational flow movement speed is inevitably reduced under the influence of resistance, the centrifugal force on the powder particles is reduced, the dispersibility of the powder is further influenced, and part of undispersed particles enter fine powder collecting equipment along with the inner ring flow, so that the classification efficiency is reduced and the classification precision is deteriorated; if the classified powder material has the characteristic of easy agglomeration, the reduction of the rotating speed of the classified powder material further causes the adhesion of the powder on the inner wall of the cyclone body, the reduction of the classification area in the cyclone body, and further causes serious problems of blockage and the like. In addition, the ascending inner circulation flow in the cyclone body and the downward outer circulation flow are in reverse directions, so that the powder particles at the top of the cyclone body are in a spiral phenomenon, when the particles are excessively gathered, the particles are discharged from the exhaust pipe, and a back-mixing short-circuit flow is formed, wherein the powder particles separated at the tail end of the exhaust pipe are entrained to return to the cyclone body, so that the classification efficiency of the classifier is influenced and needs to be improved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide superfine powder gas-phase grading equipment which solves the problems of uneven powder particle size distribution, low grading precision and low grading efficiency caused by the reduction of the rotational flow movement speed of superfine powder and back-mixing short-circuit flow in a cyclone.

In order to achieve the purpose, the invention provides the following technical scheme:

a gas phase grading device for superfine powder comprises a disperser provided with an upper end inlet, a side air inlet and a lower end outlet, wherein the upper end inlet of the disperser is connected with a feeder, the side air inlet of the disperser is communicated with a blower, and the lower end outlet of the disperser is connected with a grader; a discharge port at the lower end of the classifier is connected with a collecting tank; a fine powder outlet pipe is arranged in the classifier, the lower end of the fine powder outlet pipe penetrates out of the lower end of the classifier, and the penetrating end of the fine powder outlet pipe is connected with a back flushing tank; the top of holding vessel is connected with first draught fan, the top of blowback jar is connected with the second draught fan, first draught fan with the air outlet of second draught fan communicates each other, and with the forced draught blower with the grader intercommunication.

Through adopting above-mentioned technical scheme, the pay-off that forms after being connected through deconcentrator and forced draught blower is assisted the inlet air pipeline, the setting of the two ejection of compact induced air pipelines and the first draught fan that form after deconcentrator and holding tank and blowback pipe are connected respectively, the return air pipeline that forms after second draught fan and forced draught blower and grader intercommunication, can effectively solve the rotational flow velocity of movement reduction of superfine powder and the internal back mixing short circuit of whirlwind and cause powder particle size distribution inhomogeneous, classification accuracy and classification efficiency lower problem, and realize the cooperative classification of raw powder between different particle sizes after classification accuracy improves, and can be directly applicable to the grading process that the average particle size is submicron level to nanometer level superfine metal powder and non-metal powder.

The invention is further configured to: the grader is including the separating chamber, the conical coarse powder room and the connection that are the back taper the porous flange of separating chamber and coarse powder room, the top feed inlet of separating chamber with the deconcentrator is connected, the lower extreme discharge gate of coarse powder room is connected with the holding vessel, porous flange with first draught fan with the air outlet intercommunication of second draught fan.

By adopting the technical scheme, the problems of uneven particle size distribution of powder particles, and lower grading precision and grading efficiency caused by the reduction of the rotational flow movement speed of the superfine powder and the back-mixing short-circuit flow in the cyclone are effectively solved.

The invention is further configured to: the porous flange is provided with a plurality of air inlets, and the air inlets are arranged along the circumferential direction at equal radians.

Through adopting above-mentioned technical scheme, the inlet port that a plurality of radian distribute such as plays the effect of guaranteeing that the feeding distributes evenly and prevent that the short circuit phenomenon from appearing.

The invention is further configured to: the air inlet is provided with 12, and the aperture is 10 mm.

Through adopting above-mentioned technical scheme, 12 inlet ports that distribute with equal radian play and guarantee that the feeding distributes evenly and prevent the effect that short circuit phenomenon appears.

The invention is further configured to: the outside of porous flange is provided with and is used for sealed induced air housing, the air outlet of first draught fan with the second draught fan with the inboard intercommunication of induced air housing.

Through adopting above-mentioned technical scheme, the induced air cover plays the effect that prevents that the circulating air who gets into the grader from weing and impurity get into.

The invention is further configured to: air outlets of the first induced draft fan and the second induced draft fan are provided with emptying pipelines; and the fine powder outlet pipe and the discharge port at the bottom of the coarse powder chamber are both provided with a vacuum pressure gauge.

Through adopting above-mentioned technical scheme, the vacuum pressure gauge plays the effect of monitoring pipeline vacuum and control hierarchical process.

The invention is further configured to: the deconcentrator include with the feeder hopper that the feeder is connected and set up the dispersion awl of the discharge end lower extreme of feeder hopper, the lower extreme of dispersion awl is provided with the positioning disk that is the back taper, the upper end setting that the fine powder goes out the powder pipe is in the lower extreme of positioning disk.

By adopting the technical scheme, the dispersing cone and the guide disc play a role in preventing the feeding powder from generating passive agglomeration phenomenon when the pipe diameter of the feeding hole is reduced.

The invention is further configured to: the discharge end of the feed hopper, the axis of the dispersion cone and the axis of the guide disc are all coincided with the axis of the separation chamber.

By adopting the technical scheme, the feeding dispersity of the powder is further improved.

The invention is further configured to: first draught fan with the air outlet of second draught fan has connected gradually heat exchanger and dust remover, the air outlet of dust remover with the grader with the forced draught blower communicates respectively, and is in the air outlet of dust remover with be provided with the nitrogen gas source between the forced draught blower.

By adopting the technical scheme, the nitrogen source plays a role in preventing the moisture and oxygen in the used medium gas from causing adverse effects on the powder in the powder grading process.

The invention is further configured to: the bottom of the collecting tank is provided with an underflow tank; an overflow tank is arranged at the bottom of the back flushing tank; the feeder is a vibration blanking machine.

By adopting the technical scheme, the uniformity, the grading precision and the grading efficiency of the particle size distribution of the powder particles are obviously improved.

In conclusion, the invention has the following beneficial effects: the problems of uneven particle size distribution of powder particles and lower grading precision and grading efficiency caused by reduction of rotational flow movement speed of superfine powder and back-mixing short-circuit flow in a cyclone are effectively solved through the feeding auxiliary air inlet pipeline, the double-discharging air inducing pipeline and the air return pipeline, and after the grading precision is improved, the synergistic grading of the raw powder among different particle sizes is realized, and the method can be directly applied to the grading process of superfine metal powder and nonmetal powder with the average particle size of submicron to nanoscale.

Drawings

Fig. 1 is a schematic view of the flow structure of the present embodiment.

Description of reference numerals: 1. a feeder; 2. a disperser; 21. a feed hopper; 22. a dispersion cone; 23. a guide plate; 3. a blower; 4. a classifier; 41. a separation chamber; 42. a coarse powder chamber; 43. fine powder discharging pipe; 44. an induced draft cover; 5. a porous flange; 51. an air inlet; 6. a collection tank; 7. an underflow tank; 8. a blowback tank; 9. an overflow tank; 101. a first induced draft fan; 102. a second induced draft fan; 103. evacuating the line; 11. a heat exchanger; 12. a dust remover; 13. a nitrogen source.

Detailed Description

In order to make the technical solution and advantages of the present invention more clear, the present invention will be further described in detail with reference to the accompanying drawings.

As shown in FIG. 1, an apparatus for gas phase classification of ultrafine powders comprises a disperser 2 having an upper inlet, a side inlet and a lower outlet. An inlet at the upper end of the disperser 2 is connected with a feeder 1, and the feeder 1 is a vibration blanking machine so as to feed materials into the disperser 2 through the feeder 1; an air inlet on the side surface of the disperser 2 is communicated with an air feeder 3 to blow off powder entering the disperser 2 through the feeder 1; the lower outlet of the disperser 2 is connected with a classifier 4 to effectively classify the powder entering the disperser 2.

A collection tank 6 is connected to a discharge port at the lower end of the classifier 4. The bottom of the collection tank 6 is provided with an underflow tank 7. At the same time, a fine powder discharge pipe 43 is provided in the classifier 4. The lower end of the fine powder outlet pipe 43 penetrates out from the lower end of the classifier 4, and the penetrating end is connected with a back-blowing tank 8. The bottom of the blowback tank 8 is provided with an overflow tank 9. Correspondingly, the top end of the collecting tank 6 is connected with a first induced draft fan 101, the top end of the back blowing tank 8 is connected with a second induced draft fan 102, air outlets of the first induced draft fan 101 and the second induced draft fan 102 are communicated with each other, and after the heat exchanger 11 and the dust remover 12 are sequentially connected, the first induced draft fan 101 and the second induced draft fan 102 are respectively communicated with the air feeder 3 and the classifier 4. Therefore, when the combination of the collecting tank 6 and the underflow tank 7 and the combination of the blowback tank 8 and the overflow tank 9 are matched, the uniformity, the grading precision and the grading efficiency of the particle size distribution of the powder particles are obviously improved. And after the feeding auxiliary air inlet pipeline formed after the disperser 2 is connected with the air feeder 3, the double-discharging air induction pipeline formed after the disperser 2 is respectively connected with the collecting tank 6 and the blowback pipe, and the first draught fan 101, and the air return pipeline formed after the second draught fan 102 is communicated with the air feeder 3 and the grader 4, the problems of uneven powder particle size distribution and lower grading precision and grading efficiency caused by the reduction of the rotational flow movement speed of the superfine powder and the back-mixing short-circuit flow in the cyclone are effectively solved, the cooperative grading of the raw powder among different particle sizes is realized after the grading precision is improved, and the method can be directly suitable for the grading process of the superfine metal powder and the nonmetal powder with the average particle size of submicron to nanometer. It should be mentioned that a nitrogen source 13 is provided between the air outlet of the dust collector 12 and the blower 3, so that the nitrogen source 13 can prevent the moisture and oxygen in the used medium gas from adversely affecting the powder during the powder classification process.

As shown in fig. 1, the classifier 4 includes a separation chamber 41 having an inverted conical shape, a coarse powder chamber 42 having a conical shape, and a porous flange 5 connecting the separation chamber 41 and the coarse powder chamber 42. The top feed inlet of separating chamber 41 is connected with disperser 2, and the lower extreme discharge gate of coarse powder chamber 42 is connected with holding vessel 6, and porous flange 5 and the air outlet intercommunication of first draught fan 101 and second draught fan 102, and then reach the purpose that effectively solves the rotational flow velocity of superfine powder and the interior back mixing short-circuit flow of whirlwind and cause powder particle size distribution inhomogeneous, classification accuracy and the lower problem of classification efficiency. Meanwhile, 12 air inlets 51 are arranged on the porous flange 5, the aperture of each air inlet 51 is 10mm, the air inlets 51 are arranged along the circumferential direction at equal radians, and the 12 air inlets 51 distributed at equal radians play roles in ensuring even feeding distribution and preventing short circuit. In order to further improve the powder classification effect, an induced draft cover 44 for sealing is provided outside the porous flange 5. The air outlets of the first induced draft fan 101 and the second induced draft fan 102 are communicated with the inner side of the induced draft cover 44, so that the induced draft cover 44 plays a role in preventing the circulating air entering the classifier 4 from being affected with damp and impurities from entering.

As shown in fig. 1, the disperser 2 includes a feed hopper 21 connected to the feeder 1 and a dispersing cone 22 provided at the lower end of the discharge end of the feed hopper 21. The lower end of the dispersion cone 22 is provided with a guide plate 23 having an inverted conical shape, and the upper end of the fine powder outlet tube 43 is provided at the lower end of the guide plate 23. Therefore, the dispersion cone 22 and the guide disc 23 play a role in preventing the fed powder from generating passive agglomeration phenomenon when the pipe diameter of the feeding port is reduced. Furthermore, the axes of the discharge end of the feed hopper 21, the dispersion cone 22 and the guide disc 23 are all set to coincide with the axis of the separation chamber 41, so as to achieve the purpose of further improving the feeding dispersion degree of the powder.

It should be mentioned that the evacuation pipelines 103 are disposed at the air outlets of the first induced draft fan 101 and the second induced draft fan 102. And vacuum pressure gauges are arranged at the discharge ports at the bottoms of the fine powder outlet pipe 43 and the coarse powder chamber 42. The vacuum pressure gauge plays a role in monitoring the vacuum degree of the pipeline and controlling the grading process.

In conclusion, the problems of uneven particle size distribution of powder particles and lower grading precision and grading efficiency caused by reduction of rotational flow movement speed of ultrafine powder and back-mixing short-circuit flow in a cyclone are effectively solved through the feeding auxiliary air inlet pipeline, the double-discharging air inducing pipeline and the air return pipeline, the synergistic grading of raw powder among different particle sizes is realized after the grading precision is improved, and the method can be directly applied to the grading process of ultrafine metal powder and nonmetal powder with the average particle size of submicron to nanoscale.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment, but all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the present invention may occur to those skilled in the art without departing from the principle of the present invention, and such modifications and embellishments should also be considered as within the scope of the present invention.