Continuous powder material jet superfine grinding system

Abstract

The invention discloses a continuous powder material jet superfine grinding system, and belongs to the technical field of micro-nano powder material grinding preparation. The powder material storage bin is connected with an outlet of the vacuum feeding machine; an outlet of the powder material storage bin is sequentially and fixedly connected with a manual gate valve, a coulter stirring arch breaking machine and a double-helix feeding machine through flanges; the high-speed airflow jet crusher comprises an incidence pipe, a jet nozzle, a mixing pipe, a throat pipe and a diffusion pipe which are sequentially connected, a mixing cavity arranged in a contracted shape is formed in the mixing pipe, an injection pipe communicated with the mixing cavity is arranged on the mixing pipe, the diffusion pipe is provided with a diffusion cavity in a gradually-expanding shape, and a pressurization connector communicated with the diffusion cavity is arranged on the diffusion pipe. The diffusion pipe is a discharge port, and an injection port of the injection pipe is flexibly connected with an outlet of the double-helix feeding machine. Powder materials to be crushed can be continuously fed into the superfine crushing and conveying system for continuous crushing, and the crushing speed and efficiency are high.

Description

Technical Field

[0001] The present invention belongs to the technical field of pulverization preparation of micro-nano powder materials, and particularly relates to a continuous powder material jet ultrafine pulverization system. Background Art

[0002] The air jet pulverization technology is an important technical means for micro-nano powder processing, and there are various forms in the current industry. Due to the low energy utilization rate of these air jet pulverization methods and poor collision and shear fragmentation effects, even with the existence of classification and reflux, rapid pulverization cannot be achieved under the premise of achieving the same fragmentation effect. In actual production, only batch pulverization can be carried out, which has process hysteresis and cannot meet the continuous production requirements of enterprises, greatly reducing production efficiency.

[0003] In order to ensure continuous production, enterprises currently mostly use the method of using multiple air jet pulverization devices in parallel to meet the working conditions, which greatly increases the equipment cost of enterprises, and also increases the energy consumption and maintenance cost of enterprises. Moreover, the pulverized materials need separate conveying equipment to transport the crushed materials to the next production link, increasing the operating cost of enterprises and having low production efficiency. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A continuous powder material jet ultrafine pulverization system, comprising:

[0006] A vacuum feeder;

[0007] A powder material storage bin connected to the outlet of the vacuum feeder; the outlet of the powder material storage bin is fixedly connected to a manual gate valve, a plow blade stirring arch breaker, and a double-screw feeder in sequence by flanges;

[0008] A high-speed air jet pulverizer, the high-speed air jet pulverizer includes an incident tube, a nozzle, a mixing tube, a throat tube, and a diffuser tube connected in sequence. The mixing tube has a mixing chamber arranged in a contraction shape. The mixing tube is provided with an injection tube communicating with the mixing chamber. The diffuser tube has a diffuser chamber arranged in a gradually expanding shape. The diffuser tube is provided with a pressurizing interface communicating with the diffuser chamber. The diffuser tube is the discharge port. The injection port of the injection tube is flexibly connected to the outlet of the double-screw feeder;

[0009] Among them, a pressure gas source is used as the incident fluid gas source, which successively passes through the incident pipe and the nozzle, forms a negative pressure in the mixing chamber, sucks in particulate powder materials as the entrained fluid through the entrainment pipe, and enters the throat pipe at a high speed after uniform mixing, where collisions occur and primary crushing is carried out; then the mixed fluid enters the diffuser pipe, the pressure rises, and compressed air is injected through the pressurization interface on the diffuser pipe to locally pressurize it. After pressurization, a stable eddy current is formed and secondary crushing is carried out; after crushing, the mixed fluid is transported to the collection end, and after dust removal, it is collected separately.

[0010] Furthermore, the high-speed gas jet mill establishes a mixed fluid mechanics model, which is specifically as follows:

[0011]

[0012] Equation ① is the pressure energy analysis of any single-channel fluid. Among them, P1 is the pressure at the starting point (Pa), P2 is the pressure at the ending point (Pa); v1 is the fluid velocity at the starting point (m / s), v2 is the fluid velocity at the ending point (m / s); ρ1 is the density of the mixed fluid at the starting point (kg / m 3 ), ρ2 is the density of the mixed fluid at the ending point (kg / m 3 ); f 1-2 is the pressure loss (Pa);

[0013] Through the fluid mechanics model, multi-segment fluid pressure, velocity and flow rate analyses are respectively carried out for the nozzle section of the incident pipe, the mixing chamber section of the entrainment pipe and the throat diffuser pipe section, and the model fluid velocity calculated according to the solid-gas mixing ratio parameter is used to achieve the optimal crushing effect;

[0014]

[0015] Equation ② is the local pressurization analysis of the diffuser pipe to obtain the equivalent area at the outlet of the diffuser pipe; among them, S is the equivalent area at the outlet of the diffuser pipe (m 2 ); C0 is the entrainment ratio coefficient, and its usual value range is 1 - 15; A is the area of the conveying pipeline (m 2 );

[0016]

[0017] Equation ③ is the local pressurization velocity analysis of the diffuser pipe; among them, v is the fluid velocity at the outlet point of the air flow increaser (m / s), R e is the Reynolds number, μ is the dynamic viscosity of the air flow through the diffuser pipe orifice (Pa·s), ρ is the density of air (kg / m 3 ), L is the flow path length (m), all of which are determined according to the characteristics of the gas source.

[0018] Further, it also includes: a feeding fan and a material suction device. Among them, the feeding fan provides kinetic energy for the powder material to be pulverized, and the feeding fan sucks the powder material to be pulverized into the vacuum feeder through the material suction device and the material suction pipeline; the vacuum feeder sends the powder material into the powder material storage bin through the feeding pipeline;

[0019] A level gauge is provided on the powder material storage bin to detect the material in the bin.

[0020] Further, the double-screw feeder is located at the outlet of the powder material storage bin. The double-screw feeder adopts an inlaid double-screw structure, uses gears for transmission, and the control method is the loss-in-weight metering method. By collecting the weight loss per unit time, the feeding rate of the double-screw feeder is calculated, and the actual feeding rate is compared with the set target feeding rate, so as to feedback control and adjust the discharge amount of the double-screw feeder, providing the required material amount for the continuous conveying and continuous pulverization of the powder material;

[0021] A bin weighing system linked with the double-screw feeder for weight accuracy control is equipped on the bracket at the bottom of the powder material storage bin.

[0022] Further, the collection end includes:

[0023] A gas-solid separator and a centrifugal dust collector connected in sequence to the discharge port of the high-speed air jet pulverizer to separately collect the pulverized materials;

[0024] A collection rotary valve is provided at the solid outlet of the gas-solid separator, and a dust removal rotary valve is provided at the discharge port of the centrifugal dust collector;

[0025] A double-inlet conveying screw, and both the collection rotary valve and the dust removal rotary valve are connected to the inlet of the double-inlet conveying screw.

[0026] Further, the gas-solid separator is located at the collection point position at the end of the conveying pipeline. A powder flow inlet is provided at the tangential position of the upper cylinder of the gas-solid separator; a spiral guide groove is provided inside the gas-solid separator, an air outlet is provided at the center position of the top, and the collection rotary valve is installed at the lower part.

[0027] Further, the dust collector includes a dust collector cylinder body. An air inlet is provided in the upper middle part of the dust collector cylinder body, a centrifugal fan is provided at the top, and the exhaust port of the centrifugal fan is connected with an exhaust pipeline; a dust removal filter element is installed inside the dust collector cylinder body; a dust removal rotary valve is installed at the lower end of the dust collector.

[0028] Further, the two feeding ports of the double-inlet conveying screw are connected by flanges and are respectively connected to the outlets of the collecting rotary valve and the dust-removing rotary valve; the conveying screw of the double-inlet conveying screw is a single-screw type, and an air flow balancer is installed at the front end of the double-inlet conveying screw, and the outlet of the conveying screw is connected to a collecting bucket or a collecting bag.

[0029] Further, the pressure gas source is pressure gas or high-pressure compressed gas not less than 0.5 MPa.

[0030] Beneficial effects:

[0031] 1. A continuous powder material jet ultrafine pulverization system provided by the present invention is a continuous and non-intermittent pulverization system. The powder material to be pulverized can be continuously fed into the ultrafine pulverization conveying system for continuous crushing, with a fast crushing speed and high efficiency.

[0032] 2. A continuous powder material jet ultrafine pulverization system provided by the present invention integrates the pulverization and conveying of powder materials. Through the primary ejecting and mixing and secondary local pressurization crushing of the high-speed air jet pulverizer, efficient pulverization of the materials can be achieved, enabling the materials to be quickly pulverized during the conveying process. While improving the efficiency, the number of equipment and the operation and maintenance costs are reduced, and the energy consumption is also greatly reduced.

[0033] 3. A continuous powder material jet ultrafine pulverization system provided by the present invention has a remote conveying function. According to the actual working conditions, the pulverized finished materials can be directly conveyed to the terminal position, reducing the production links, reducing the number of equipment, and improving the work efficiency.

[0034] 4. A continuous powder material jet ultrafine pulverization system provided by the present invention omits the classification device, reduces the number of motors, reduces the energy consumption of the system equipment, and reduces the operation cost. Description of the drawings

[0035] Figure 1 is the overall structural schematic diagram of a continuous powder material jet ultrafine pulverization system provided by the present invention;

[0036] Figure 2 is the structural schematic diagram of the high-speed jet crusher;

[0037] Figure 3 is the particle size analysis report before pulverization of a continuous powder material jet ultrafine pulverization system provided by the present invention, with silicon powder as the sample material;

[0038] Figure 4 is the particle size analysis report after pulverization of a continuous powder material jet ultrafine pulverization system provided by the present invention, with silicon powder as the sample material;

[0039] Figure 5 It is a comparison table of the particle sizes of silicon lattice powder as the sample material before and after crushing;

[0040] In the figure: 1. Feeding fan; 2. Powder material storage bin; 3. Vacuum feeder; 4. Suction device; 5. Manual gate valve; 6. Plow blade stirring arch breaker; 7. Double screw feeder; 8. Roots blower; 9. Weighing sensor; 10. High-speed air jet mill; 10-1. Inlet pipe; 10-2. Nozzle; 10-3. Mixing pipe; 10-4. Throat pipe; 10-5. Diffuser pipe; 10-6. Front pressure transmitter interface; 10-7. Ejector pipe; 10-8. Vacuum pressure transmitter interface; 10-9. Boosting interface; 10-10. Rear pressure transmitter interface; 11. Quick pneumatic valve; 12. Gas-solid separator; 13. Collection rotary valve; 14. Dust collector; 15. Dust removal rotary valve; 16. Double-inlet conveying screw. Specific implementation mode

[0041] Example 1

[0042] Reference Figure 1 - Figure 2 , a continuous powder material jet ultrafine pulverization system, comprising:

[0043] Vacuum feeder 3;

[0044] A powder material storage bin 2 connected to the outlet of the vacuum feeder 3; the outlet of the powder material storage bin 2 is fixedly connected to the manual gate valve 5, the plow blade stirring arch breaker 6 and the double screw feeder 7 in sequence by flanges; the double screw feeder 7 is an embedded precision metering double screw feeder;

[0045] High-speed air jet mill 10, the high-speed air jet mill 10 includes an inlet pipe 10-1, a nozzle 10-2, a mixing pipe 10-3, a throat pipe 10-4 and a diffuser pipe 10-5 connected in sequence. The mixing pipe 10-3 has a mixing cavity arranged in a contracted shape. The mixing pipe 10-3 is provided with an ejector pipe 10-7 communicating with the mixing cavity. The diffuser pipe 10-5 has a straight cavity and a diffusing cavity in a gradually expanding shape. Among them, the straight cavity is located on one side of the throat pipe 10-4. The straight cavity section of the diffuser pipe 10-5 is provided with a boosting interface 10-9 communicating with the diffusing cavity. The diffuser pipe 10-5 is the discharge port. The ejector port of the ejector pipe 10-7 is flexibly connected to the outlet of the double screw feeder 7;

[0046] Among them, using a pressure gas source as the incident fluid gas source, it successively passes through the incident pipe 10-1 and the nozzle 10-2, forms a negative pressure in the mixing chamber, sucks in particulate powder materials as the entrained fluid through the entrainment pipe 10-7, and after uniform mixing, enters the throat pipe 10-4 at high speed, forms a collision and performs primary crushing; then the mixed fluid enters the diffuser pipe 10-5, the pressure rises, and compressed air is injected through the pressure boosting interface 10-9 on the diffuser pipe 10-5 to locally boost the pressure. After boosting, a stable eddy current is formed and secondary crushing is performed; after crushing, the mixed fluid is transported to the collection end, and after dust removal, it is collected separately.

[0047] In this embodiment, the high-speed gas jet mill 10 adopts the Venturi principle, uses a pressure gas source as the incident fluid gas source, and realizes two-stage crushing of primary crushing and secondary crushing; among them, a front pressure transmitter interface 10-6 is provided on the incident pipe 10-1, a vacuum pressure transmitter interface 10-8 is provided on the mixing pipe 10-3, and a rear pressure transmitter interface 10-10 is provided on the gradually expanding cavity section of the diffuser pipe 10-5.

[0048] In this embodiment, the high-speed gas jet mill establishes a mixed fluid mechanics model, which is specifically as follows:

[0049]

[0050] Equation ① is the pressure energy analysis of any single-channel fluid. Among them, P1 is the pressure (Pa) at the starting point, P2 is the pressure (Pa) at the ending point; v1 is the fluid velocity (m / s) at the starting point, v2 is the fluid velocity (m / s) at the ending point; ρ1 is the density of the mixed fluid (kg / m 3 ) at the starting point, ρ2 is the density of the mixed fluid (kg / m 3 ) at the ending point; f 1-2 is the pressure loss (Pa);

[0051] Through the fluid mechanics model, multi-section fluid pressure, velocity and flow analysis are respectively carried out on the nozzle section of the incident pipe, the mixing chamber section of the entrainment pipe and the throat diffuser pipe section, and the model fluid velocity calculated according to the solid-gas mixing ratio parameter is used to achieve the optimal crushing effect;

[0052]

[0053] Equation ② is the local pressure boosting analysis of the diffuser pipe to calculate the equivalent area at the outlet of the diffuser pipe; among them, S is the equivalent area (m 2 ) at the outlet of the diffuser pipe; C0 is the entrainment ratio coefficient, and its usual value range is 1-15; A is the area of the conveying pipeline (m 2 );

[0054]

[0055] Equation ③ is for the analysis of the local pressure increase rate of the diffusion tube. Among them, v is the fluid flow velocity at the outlet point of the air flow extender (m / s), R e is the Reynolds number, μ is the dynamic viscosity of the air flow through the 10-5 openings of the diffusion tube (Pa·s), ρ is the density of air (kg / m 3 ), L is the length of the flow channel (m), all determined according to the characteristics of the gas source.

[0056] The continuous powder material injection ultrafine pulverization system provided in this embodiment further includes: a feeding fan 1 and a material suction device 4. Among them, the feeding fan 1 provides kinetic energy for the powder material to be pulverized. The feeding fan 1 sucks the powder material to be pulverized into the vacuum feeder 3 through the material suction device 4 and the material suction pipeline; the vacuum feeder 3 sends the powder material into the powder material storage bin 2 through the feeding pipeline;

[0057] A level gauge is provided on the powder material storage bin 2 to detect the material in the bin; when a high level is detected, the feeding stops.

[0058] In this embodiment, the double-screw feeder 7 is located at the outlet of the powder material storage bin 2. The double-screw feeder 7 adopts an inlaid double-screw structure, uses gears for transmission, and the control method is the weight-loss metering method. By collecting the weight loss per unit time, the feeding rate of the double-screw feeder 7 is calculated, and the actual feeding rate is compared with the set target feeding rate, so as to feedback control and adjust the discharge amount of the double-screw feeder 7 to provide the required material amount for the continuous conveying and continuous pulverization of the powder material;

[0059] A bin weighing system that is linked with the double-screw feeder 7 for weight accuracy control is equipped on the bracket at the bottom of the powder material storage bin 2.

[0060] In this embodiment, the collection end includes:

[0061] A gas-solid separator 12 and a centrifugal dust collector 14 that are sequentially connected to the discharge port of the high-speed air flow jet pulverizer 10 to separately collect the pulverized material;

[0062] A collection rotary valve 13 is provided at the solid outlet of the gas-solid separator 12, and a dust removal rotary valve 15 is provided at the discharge port of the centrifugal dust collector 14;

[0063] A double-inlet conveying screw 16, and both the collection rotary valve 13 and the dust removal rotary valve 15 are connected to the inlets of the double-inlet conveying screw 16.

[0064] Among them, the gas-solid separator 12 is located at the collection point position at the end of the conveying pipeline. A powder material flow inlet is provided at the tangential position of the upper cylinder of the gas-solid separator 12; a spiral guide groove is provided inside the gas-solid separator 12, an air outlet is provided at the center position of the top, and a collection rotary valve 13 is installed at the lower part.

[0065] The dust collector 14 includes a dust collector cylinder body. An air inlet is provided in the upper middle part of the dust collector cylinder body, and a centrifugal fan is provided at the top. The air outlet of the centrifugal fan is connected to an exhaust air duct; a dust removal filter element is installed inside the dust collector cylinder body; a dust removal rotary valve 15 is installed at the lower end of the dust collector 14.

[0066] The two feeding ports of the double-inlet conveying screw 16 are connected by a flange connection method and are respectively connected to the outlets of the collecting rotary valve 13 and the dust removal rotary valve 15; the conveying screw of the double-inlet conveying screw 16 is a single-screw method. An air flow balancer is installed at the front end of the double-inlet conveying screw 16, and the outlet of the double-inlet conveying screw 16 is connected to a collecting bucket or a collecting bag.

[0067] In this embodiment, the pressure air source is the pressure gas provided by the Roots blower 8 or the high-pressure compressed gas not lower than 0.5 MPa.

[0068] Embodiment 2

[0069] This embodiment is further set on the basis of the continuous powder material jet ultrafine pulverization system provided in Embodiment 1.

[0070] A continuous powder material jet ultrafine pulverization system includes: a suction feeder 4 is connected to the inlet of a vacuum feeding machine 3 through a suction pipeline; the vacuum feeding machine 3 is connected to the feeding port of a powder material storage bin 2 through a feeding pipeline; the powder material storage bin 2 is conical, and a mechanical arch breaking device and multiple groups of pneumatic arch breaking devices are installed on the inner side wall of the conical cylinder; multiple groups of pneumatic arch breaking devices are connected to a high-pressure air source; between the outer wall of the powder material storage bin 2 and the bin support legs, a weighing sensor 9 is installed at the lower end of the bin support legs, and multiple groups of level gauges are equipped on the outer wall of the powder material storage bin 2.

[0071] The outlet of the powder material storage bin 2 is sequentially connected to a manual gate valve 5, a plowshare agitator arch breaker 6 and a double-screw feeder 7; the outlet of the double-screw feeder 7 is connected to the inlet of a quick pneumatic valve 11 through a flexible connection, and the outlet of the quick pneumatic valve 11 is connected to the feeding port of a high-speed air flow jet pulverizer 10.

[0072] The air outlet of the Roots blower 8 is connected to the working fluid inlet of the high-speed air flow jet pulverizer 10 through a pipeline. The outlet of the high-speed air flow jet pulverizer 10 is connected to the inlet of a gas-solid separator 12 through a conveying pipeline. The discharge outlet of the gas-solid separator 12 is connected to the inlet of a collecting rotary valve 13. The outlet of the collecting rotary valve 13 is flange-connected to the feeding port of the double-inlet conveying screw 16. The air outlet of the gas-solid separator 12 is connected to the air inlet of the dust collector 14; the outlet of the ash hopper at the lower part of the dust collector cylinder body is connected to the inlet of the dust removal rotary valve 15, and the outlet of the dust removal rotary valve 15 is connected to the feeding port of the double-inlet conveying screw 16.

[0073] The discharge port of the double-inlet conveying screw 16 is equipped with a quick-connect fitting, which can be directly collected into the storage bin of the next process, or can be connected to the material collection bag through this quick-connect fitting.

[0074] Specifically, the powder material to be pulverized utilizes the kinetic energy provided by the feeding blower 1 and is inhaled into the vacuum feeding machine 3 through the suction device 4 and the suction pipeline; the vacuum feeding machine 3 sends the powder material into the powder material storage bin 2 through the feeding pipeline; the level gauge installed on the powder material storage bin 2 detects the material in the bin, and stops feeding when the high level is detected.

[0075] In this embodiment, the Roots blower 8 serves as the power source of the conveying and pulverizing system, providing sufficient power for the continuous powder material jet ultrafine pulverizing system; when the Roots blower 8 starts, the system will automatically detect the state of the working flow field in the high-speed gas flow jet pulverizer 10, and open the quick pneumatic valve 11 when the requirements for system operation are met;

[0076] The double-screw feeder 7 sends the powder material in the powder material storage bin 2 into the mass transfer cavity of the high-speed gas flow jet pulverizer 10 through the feeding quick pneumatic valve 11 and the feed inlet of the high-speed gas flow jet pulverizer 10, and then through the outlet of the high-speed gas flow jet pulverizer 10, enters the conveying pipeline through jet breaking and pressure-increasing breaking;

[0077] The inner side wall of the conical cylinder of the powder material storage bin 2 is equipped with a mechanical arch-breaking device and multiple groups of pneumatic arch-breaking devices, which are used to assist the powder material in the bin to smoothly enter the feed inlet of the double-screw feeder 7.

[0078] In this embodiment, the control mode of the double-screw feeder 7 is a weight-loss control mode that adjusts the rotation speed of the double-screw feeder 7 by PID according to the change amount of the material reduction in the powder material storage bin 2 detected by the weighing sensor 9 in real time and the set conveying and pulverizing target amount by the user.

[0079] In this embodiment, the air inlet of the gas-solid separator 12 is connected to the outlet of the conveying pipeline. The lower part of the gas-solid separator 12 is conical for collecting the pulverized finished product materials, and the outlet of the gas-solid separator 12 is connected with a collecting rotary valve 13;

[0080] In this embodiment, the top exhaust port of the gas-solid separator 12 is connected to the air inlet of the dust collector 14 through a pipeline. The lower part of the dust collector 14 is used to collect the powder material filtered by the dust collector filter element, and its outlet is connected with a dust-removing rotary valve 15.

[0081] In this embodiment, the outlets of the collecting rotary valve 13 and the dust-removing rotary valve 15 are respectively connected to the two feed inlets of the double-inlet conveying screw 16, and the outlet of the double-inlet conveying screw 16 is connected to the material collection bucket or the material collection bag through a quick-connect fitting.

[0082] As Figure 3 、 Figure 4 shown, taking silicon grid powder with a dosing rate of 60 kg / hour as a sample, with an operation time of 30 minutes, using a BT-9300ST laser particle size analyzer, the original particle size and the particle size after pulverization of the silicon grid powder were respectively detected. According to Figure 3 、 Figure 4 the data in, it can be seen that after pulverization by a continuous powder material jet ultrafine pulverization system, the volume mean diameter of the silicon grid powder decreased by 33.3%, the surface area mean diameter decreased by 46.7%, the number mean diameter decreased by 52.4%, and the peak particle size decreased by 75.2%.

[0083] Specifically, Figure 5 taking the silicon grid powder as the sample material, through the comparative analysis of the particle size before and after pulverization, it can be clearly seen that after pulverization by a continuous powder material jet ultrafine pulverization system, the particle size of the material with a particle size of D03 decreased by 51.97%, the particle size of the material with a particle size of D06 decreased by 52.51%, the particle size of the material with a particle size of D10 decreased by 51.55%, the particle size of the material with a particle size of D16 decreased by 48.59%, the particle size of the material with a particle size of D25 decreased by 45.09%, the particle size of the material with a particle size of D50 decreased by 45.60%, the particle size of the material with a particle size of D75 decreased by 38.02%, the particle size of the material with a particle size of D84 decreased by 28.91%, the particle size of the material with a particle size of D90 decreased by 21.59%, and the particle size of the material with a particle size of D97 decreased by 12.27%, achieving the effect of ultrafine pulverization.

[0084] The above is only a preferred embodiment of the present invention, and does not impose any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A continuous powder material jet ultrafine grinding system, characterized in that Comprising: Vacuum feeder; Powder material storage bin connected to the outlet of the vacuum feeder; The outlet of the powder material storage bin is fixedly connected to a manual gate valve, a ploughshare agitator for breaking arch and a double-screw feeder in sequence by flanges; High-speed air jet pulverizer, the high-speed air jet pulverizer includes an incident pipe, a nozzle, a mixing pipe, a throat pipe and a diffuser pipe connected in sequence, a mixing cavity arranged in a contraction shape is provided in the mixing pipe, an ejector pipe communicated with the mixing cavity is arranged on the mixing pipe, the diffuser pipe has a diffuser cavity arranged in a gradually expanding shape, a pressurizing interface communicated with the diffuser cavity is arranged on the diffuser pipe, the diffuser pipe is the discharge port, and the ejector port of the ejector pipe is flexibly connected to the outlet of the double-screw feeder; Wherein, using a pressure air source as the incident fluid air source, passing through the incident pipe and the nozzle in sequence, a negative pressure is formed in the mixing cavity, sucking particulate powder material as the ejector fluid through the ejector pipe, uniformly mixing and then entering the throat pipe at high speed to form collisions and perform primary pulverization; then the mixed fluid enters the diffuser pipe, the pressure rises, and compressed air is injected through the pressurizing interface on the diffuser pipe to locally pressurize it, and a stable eddy current is formed after pressurization and secondary crushing is performed; after crushing, the mixed fluid is transported to the collection end, and after dust removal, it is collected separately.

2. The continuous powder material jet ultrafine grinding system according to claim 1, characterized in that The high-speed air jet pulverizer establishes a mixed fluid mechanics model, specifically as follows: Equation ① is for any single-channel fluid pressure energy analysis, where P1 is the pressure at the starting point (Pa), P2 is the pressure at the ending point (Pa); v1 is the fluid flow velocity at the starting point (m / s), v2 is the fluid flow velocity at the ending point (m / s); ρ1 is the density of the mixed fluid at the starting point (kg / m 3 ), ρ2 is the density of the mixed fluid at the ending point (kg / m 3 ); f 1-2 is the pressure loss (Pa); Through the fluid mechanics model, multi-section fluid pressure, velocity and flow rate analysis are respectively carried out on the incident pipe nozzle section, the ejector pipe mixing cavity section and the throat pipe diffuser pipe section, and the model fluid velocity calculated according to the solid-gas mixing ratio parameter is used to achieve the optimal crushing effect; Equation ② is for the local pressure increase analysis of the diffuser pipe to obtain the equivalent area at the diffuser pipe outlet; where S is the equivalent area at the diffuser pipe outlet (m 2 ); C0 is the entrainment ratio coefficient, and its general value range is 1 - 15; A is the area of the conveying pipeline (m 2 ); Equation ③ is the analysis of the local pressure increase rate of the diffusion tube; where, v is the fluid flow velocity at the outlet point of the air flow extender (m / s), R e is the Reynolds number, μ is the dynamic viscosity of the air flow through the openings of the diffusion tube (Pa·s), ρ is the density of air (kg / m 3 ), and L is the length of the flow channel (m), all determined according to the characteristics of the gas source.

3. The continuous powder material jet ultrafine grinding system according to claim 1, characterized in that, Also comprising: Feeding fan and suction device, wherein, the feeding fan provides kinetic energy for the powder material to be pulverized, and the feeding fan sucks the powder material to be pulverized into the vacuum feeder through the suction device and the suction pipeline; the vacuum feeder sends the powder material into the powder material storage bin through the feeding pipeline; A level gauge is arranged on the powder material storage bin to detect the material in the bin.

4. The continuous powder material injection ultrafine grinding system according to claim 1, wherein, The double-screw feeder is located at the outlet of the powder material storage bin, the double-screw feeder adopts an inlaid double-screw structure, uses a gear as the transmission, the control method is the weight loss metering method, by collecting the weight loss per unit time, calculating the feeding rate of the double-screw feeder, and comparing the actual feeding rate with the set target feeding rate, so as to feedback control and adjust the discharge amount of the double-screw feeder to provide the required material amount for the continuous conveying and continuous pulverization of the powder material; A bin weighing system linked with the double-screw feeder for weight accuracy control is equipped on the bracket at the bottom of the powder material storage bin.

5. The continuous powder material jet ultrafine grinding system according to claim 1, characterized in that, The collection end includes: An air-solid separator and a centrifugal dust collector connected in sequence to the discharge port of the high-speed air jet pulverizer to separately collect the pulverized materials; A collection rotary valve is arranged at the solid outlet of the air-solid separator, and a dust removal rotary valve is arranged at the discharge port of the centrifugal dust collector; Double-inlet conveying screw, both the collection rotary valve and the dust removal rotary valve are connected to the inlet of the double-inlet conveying screw.

6. The continuous powder material jet ultrafine pulverization system according to claim 5, wherein The gas-solid separator is located at the collection point at the end of the conveying pipeline. A powder flow inlet is provided at the tangential position of the upper cylinder of the gas-solid separator. A spiral guide groove is arranged inside the gas-solid separator, an air outlet is provided at the central position of the top, and the collection rotary valve is installed at the lower part.

7. The continuous powder material injection ultrafine grinding system according to claim 5, characterized in that, The dust collector includes a dust collector cylinder body. An air inlet is provided in the upper middle part of the dust collector cylinder body, a centrifugal fan is provided at the top, and an exhaust air duct is connected to the exhaust air outlet of the centrifugal fan. A dust removal filter element is installed inside the dust collector cylinder body. A dust removal rotary valve is installed at the lower end of the dust collector.

8. The continuous powder material jet ultrafine grinding system according to claim 5, characterized in that, The two feeding ports of the double-inlet conveying screw are connected by flanges and are respectively connected to the outlets of the collection rotary valve and the dust removal rotary valve. The conveying screw of the double-inlet conveying screw is in a single-screw mode. An air flow balancer is installed at the front end of the double-inlet conveying screw, and the outlet of the conveying screw is connected to a collection barrel or a collection bag.

9. The continuous powder material jet ultrafine grinding system according to claim 1, characterized in that, The pressure gas source is a pressure gas or a high-pressure compressed gas not less than 0.5 MPa.

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