CN108421646B

CN108421646B - Vertical wet-process particle classification centrifugal machine

Info

Publication number: CN108421646B
Application number: CN201710081390.3A
Authority: CN
Inventors: 谢小飞
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-02-15
Filing date: 2017-02-15
Publication date: 2020-07-28
Anticipated expiration: 2037-02-15
Also published as: CN108421646A

Abstract

The invention aims to provide a vertical wet particle grading centrifuge which comprises a discharging rotary joint, a hollow transmission shaft, a separation turbine, a rotor and a cavity. The discharging rotary joint is arranged at the top of the hollow transmission shaft; the hollow transmission shaft is arranged on the transmission seat; the cavity mainly provides a closed separation space and is divided into an upper cavity and a lower cavity; a rotor installed at a lower end of the separation turbine; the separation turbine is arranged at the lowest end of the hollow transmission shaft; the design mechanism, the rotating speed, the pressure and the valve flow control are realized, so that the particle wet-method particle classification centrifugation is realized.

Description

Vertical wet-process particle classification centrifugal machine

Technical Field

The invention belongs to the field of particle preparation, classification and separation equipment, and particularly relates to a vertical wet particle classification centrifugal machine.

Background

After the particles in the slurry are subjected to ultrafine grinding or dispersion by a medium stirring mill, the ground or dispersed fine particles with different particle sizes are in particle size distribution of different particles (i.e., large-particle size particles, medium-particle size particles and small-particle size particles). However, the produced product with wide particle size distribution is difficult to meet the requirements of modern science and technology and application. At present, according to the fine particle materials with different particle diameters in the slurry, the most common particle classification method adopts the methods of screening, gravity settling, centrifugal separation and the like, although a certain effect of particle classification can be achieved, the processes are various, the operation is complex, the classification efficiency is low, the mass production of particle classification is not facilitated, the particle classification effect is not ideal, and especially the effective submicron or nanoscale ultrafine particle classification is difficult to achieve by the process and the technology. Therefore, the vertical wet particle grading centrifuge has important practical significance and application value for grading micron-sized, submicron-sized and nanoscale particles in slurry.

Disclosure of Invention

The invention aims to provide a vertical wet particle grading centrifuge which comprises a discharging rotary joint, a hollow transmission shaft, a separation turbine, a rotor and a cavity.

The discharging rotary joint is arranged at the top of the hollow transmission shaft, the transmission shaft rotates, and the discharging rotary joint does not rotate to ensure directional discharging.

The hollow transmission shaft is arranged on the transmission seat, plays a role in transmission of the rotor, and the shaft hole of the hollow transmission shaft provides a discharge channel for small-particle-size particles.

The cavity is mainly provided with a closed separation space and is divided into an upper cavity and a lower cavity, the lower cavity is in a conical structure, the bottom of the lower cavity is provided with a feed inlet, the circumference of the maximum position of the inverted cone of the lower cavity is provided with one or more outlets for large-particle-size particles, and the highest side wall of the upper cavity is provided with one or more outlets for medium-particle-size particles.

The rotor is arranged at the lower end of the separation turbine and is in an olive shape, and when the rotor rotates at a high speed, the rotating flow field generates strong centrifugal force to enable particles in the slurry to be regularly distributed from small to large in the radial direction of the cavity.

The separation turbine is arranged at the lowest end of the hollow transmission shaft, and generates strong centrifugal force during rotation, so that large and medium-particle-size particles are thrown to a space far away from the turbine in the radial direction, small-particle-size particles are distributed around the separation turbine due to small inertia, and under the pressure of the feed pump, the small-particle-size particles can overcome the centrifugal force, enter the inner cavity of the turbine and the shaft hole and are discharged.

Compared with the prior art, the invention has the following advantages and effects:

1) because the rotor and the separation turbine both generate strong centrifugal force during rotation, particle groups in a rotating flow field are distributed according to the rule of figure 2, materials with larger particle size particles are thrown to the periphery far away from the axis and cannot enter a discharge channel of the hollow transmission shaft, small particle size particles are distributed in the space near the axis of the rotating flow field, and are pressed into an inner cavity and a shaft hole of the separation turbine under the pressure action of the feeding pump and the action of the centrifugal force, so that the small particle size particles are discharged from the hollow shaft; the large and medium particle diameter particles are discharged from the large and medium particle diameter particle discharge ports of the cavity respectively.

2) Because the influence of the size of the gap of the filter screen is avoided, the discharge flow is large, and the production efficiency is high.

3) Because the designed grading and separating structure is adopted, the particle grading efficiency is high.

Drawings

The invention will be further explained with reference to the drawings

FIG. 1 is a schematic diagram of the structure of a vertical wet particle classification centrifuge of the present invention, wherein: 1-rotor, 2-lower cavity, 3-upper cavity, 4-separation turbine, 5-mechanical seal, 6-transmission seat, 7-belt pulley, 8-hollow transmission shaft and 9-discharging rotary joint.

Figure 2 is a graph showing the distribution of particles within a high velocity rotating flow field in accordance with the present invention.

FIG. 3 is a schematic view of a split turbine configuration of the present invention.

Detailed Description

For a better understanding of the present invention, reference is made to the following further description taken in conjunction with the accompanying drawings. As shown in figure 1, the hollow transmission shaft of the vertical wet particle grading centrifuge is fixed on the transmission seat and plays the roles of transmitting power and providing a discharge channel. The upper end of the device is provided with a discharging rotary joint, and the lower end is provided with a separation turbine.

The cavity is divided into an upper cavity and a lower cavity, the upper cavity is a conical hollow structure, and one or more medium-particle-size particle outlets are formed in the upper circumference; the lower cavity is in an inverted cone structure, a feed inlet is formed in the center of the bottom of the lower cavity, and one or more outlets for particles with large particle size are formed in the position with the largest diameter of the lower cavity. The slurry enters the cavity from the feed inlet at the bottom of the cavity, is stirred by the rotor to move circularly, and is lifted upwards in a spiral motion under the pressure action of the feed pump. The population of particles in the slurry formed a distribution as shown in figure 2. The large-particle-size particles are lifted along the space of the lower cavity close to the inner wall, and when reaching the maximum diameter position of the inner wall of the cavity, the large-particle-size particles are discharged from the large-particle-size particle outlet. The medium-size particles and the small-size particles continuously rise, individual large-size particles and large-size particles mixed in the medium-size particles and the small-size particles can continuously move upwards for a certain distance under the action of the pump, but in the rising process, when the large-size particles spirally rise along the inner wall of the upper cavity, a downward movement trend is formed under the action of the pressure component force of the inclined wall, and the large-size particles spirally move towards the direction with the largest diameter of the cavity and move towards the large-size particle outlet. The medium-particle-size particles rise in the fluid intermediate layer, and when reaching the top, the medium-particle-size particles are thrown to the outer layer by centrifugal force and are discharged from a medium-particle-size particle outlet; the small-particle-size particles rise along the inner layer close to the rotor, and when the small-particle-size particles reach the periphery of the small-particle-size particle separation turbine, the small-particle-size particles overcome the centrifugal force of the separation turbine under the action of the feed pump, enter the inner cavity of the turbine and the shaft hole and are discharged from the shaft hole of the hollow transmission shaft. The ascending process is the process that the particle groups are regularly distributed and graded and separated by guide driving, and the grading weight proportion of three graded products, namely large-particle-size particles, medium-particle-size particles and small-particle-size particles can be controlled by controlling the rotating speed, the pressure and the flow of valves of a medium-particle-size particle discharge port and a large-particle-size particle discharge port, so that the graded and separated of three grades can be realized. Similarly, the valve of the discharge port of the medium-particle-size particles is closed, and the flow of the valve of the discharge port of the large-particle-size particles is controlled to realize the classification separation of two grades of small-particle-size particles and large-particle-size particles. The process can repeatedly carry out grading for many times, can obtain ideal and accurate products with narrow particle size distribution of particles, and realizes accurate grading separation.

The upper part of the rotor is of a conical structure and is connected with the separation turbine, the lower part of the rotor is of an inverted conical structure, a rotating flow field is generated during rotation, and particles with larger particle sizes are thrown to an annular space which is farther from an axis center more easily and more greatly under the action of centrifugal force. The mode of reasonable distribution of the particle size and the inertia force enables the classification effect to be good, the classification efficiency to be high, and small-particle-size particles, medium-particle-size particles and large-particle-size particles can be successfully arranged in order from the axis to the inner wall of the cavity.

The separation turbine 4 is arranged at the lowest end of the hollow transmission shaft, when the separation turbine rotates, the centrifugal force generated drives the fluid to do radial circular motion, and the particle groups are orderly distributed from small particle size to large particle size in the radial direction, the smaller the centrifugal force applied to the particles with smaller particle size, the closer the particles are to the turbine, the more easily the centrifugal force applied to the separation turbine can be overcome under the pressure action of the feeding pump, the particles enter the hollow transmission shaft 1 and are discharged, and therefore effective classification is achieved.

Based on the above mechanism, the inventors have produced a vertical wet particle size classification centrifuge with a volume of 1.5 liters and a power of 3 kilowatts. The results of the comparison test with the conventional classifier show that the vertical wet particle classification centrifugal separator has remarkable classification effect, and ultrafine particles with +/-50 nanometer size fraction can be successfully classified and separated by controlling the flow and the rotating speed of each outlet.

2) The grading efficiency of the grading machine is 80% higher than that of the traditional grading machine, and consumables such as filter cloth, separation net and filter element are not consumed.

3) The discharging temperature is obviously reduced, the energy consumption in the grading separation process is little, the temperature rise is hardly generated, and the energy is saved.

The vertical wet-method particle grading centrifuge has high efficiency and is suitable for grading medium and low viscosity fine particle slurry. The particle grading centrifuge can be popularized and used on medium and low viscosity fine particle slurry. If the invention is widely applied in various industries with different fine particle slurry with medium and low viscosity and in various industries, obvious economic benefits can be generated in the aspects of high efficiency, energy conservation and emission reduction. The method has good popularization value and application prospect, and can be widely applied to the field of grading fine particles in slurry with different medium and low viscosities.

Claims

1. A vertical wet particle grading centrifuge comprises a discharge rotary joint, a hollow transmission shaft, a separation turbine, a rotor and a cavity; the cavity is divided into an upper cavity and a lower cavity, the upper cavity is a conical hollow structure, and one or more medium-particle-size particle outlets are formed in the upper circumference; the lower cavity is of an inverted cone structure, a feed inlet is formed in the center of the bottom of the lower cavity, and one or more outlets for large-particle-size particles are formed in the position with the largest diameter of the lower cavity; the upper part of the rotor is of a conical structure and is connected with the separation turbine, the lower part of the rotor is of an inverted conical structure, a rotating flow field is generated during rotation, and particle groups can be successfully arranged in order from the axis to the inner wall direction of the cavity according to small-particle-size particles, medium-particle-size particles and large-particle-size particles; the separation turbine is arranged at the lowest end of the hollow transmission shaft, and when the separation turbine rotates, the centrifugal force generated drives the fluid to do radial circular motion, and the particle groups are orderly distributed from small particle size to large particle size in the radial direction, and the smaller the centrifugal force is applied to the particles with smaller particle size; the ascending process is the process that the particle groups are regularly distributed and graded separation is realized by guide driving, and the grading weight proportion of three graded products, namely large-particle-size particles, medium-particle-size particles and small-particle-size particles can be controlled by controlling the rotating speed, the pressure and the flow of valves of a medium-particle-size particle discharge port and a large-particle-size particle discharge port, so that the graded separation of three grades is realized; similarly, the valve of the discharge port of the medium-particle-size particles is closed, and the flow of the valve of the discharge port of the large-particle-size particles is controlled to realize the classification separation of two grades of small-particle-size particles and large-particle-size particles.