JPS628218B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic pulverizing apparatus suitable for pulverizing pulverized material having a small bulk density, such as rice husk.

A large amount of rice husks generated at rice centers, etc.
In recent years, it has been gaining attention as a way to utilize it, such as pulverizing it to about 74 μm and using it as a filler for resin-based materials, or as a humidity control material for compost, and some of them have specialized machines. has also been put into practical use.

The conventional machine used for such rice husk crushing processing is a mechanical impact crusher as shown in FIG. , crushed material inlet 3
The rice husks fed in from the casing are finely crushed by a runner 2 and taken out as a crushed product through an outlet 4. However, rice husk has a hard shell surface and is highly flexible due to its fibrous composition, making it difficult to crush.In the crusher shown in Figure 1, the crushing blades wear out quickly. The problem is that it is not possible to stably obtain a crushed product with a fine particle size over a long period of time. For this purpose, a method called swelling and softening treatment is also carried out, in which water is added to the rice hulls in the pre-processing process, and the rice hulls are heated and compressed before being sent to the pulverizer. The process becomes complicated, such as the need for a drying operation to remove moisture. For this reason, there is a desire for a rice husk crusher with good crushing performance and efficiency to replace the mechanical crusher mentioned above.

On the other hand, recently, a new electromagnetic crusher has been developed that uses a moving magnetic field to apply electromagnetic force to a working piece to process crushed materials. Next, the structure and principle of this crusher will be described with reference to FIGS. 2 and 3. In the figure, reference numeral 5 denotes a processing container that accommodates a large number of working pieces 7 made of ferromagnetic or non-magnetic conductive material along with crushed material 6 as the object to be processed. Moving magnetic field generating devices 8 and 9, which are well known as so-called linear motors, are arranged facing each other, and their moving magnetic fields φ ₁ and φ ₂ are set in opposite directions.

With this configuration, magnetization and eddy current are generated in the working piece 7 placed in the magnetic field where the moving magnetic fields φ ₁ and φ ₂ act, and a current force acts on the working piece 7 based on the interaction with the moving magnetic field. This allows working piece 7
is subjected to a translational force in the direction of the moving magnetic field, a levitation force, and a magnetic torque rotating around the center of gravity.Furthermore, collisions between the working pieces and collisions between the working pieces and the container wall are added, and a complicated and complicated movement occurs inside the container 5. Causes intense random motion. Due to this random movement, the crushed material 6 is crushed by impact and by abrasion.

This electromagnetic crusher differs from the conventional mechanical crusher shown in Figure 1 in that it grinds by random movement of the working pieces, and is stable over a long period of time without problems such as wear of the crushing blades. This provides excellent pulverization performance, and the pulverization process time can be shortened. According to experiments conducted by the generator, when rice husks were crushed using this electromagnetic crusher, the crushing time was shorter than that of the crusher shown in Figure 1.
It has also been confirmed that the crushing limit range is wider than that of conventional mechanical crushers, and fine crushing is also possible.

Therefore, when pulverizing rice hulls using such an electromagnetic pulverizer, the pulverized material 6 is transferred to the processing container 5.
The batch method, in which the powder is pulverized until the end while it is housed in the container, has the following drawbacks in terms of operational efficiency and pulverization performance. It is the bulk density of rice husk
It is extremely small at 0.12t/ ^cm3 , and when rice husks are stored together with the working piece 7 in the processing container 5 at the appropriate filling rate at the beginning of operation and the operation is started, coarsely pulverized rice husks can be obtained in a short time. Since the bulk is reduced to 1/2 to 1/4 of the initial filling amount, the subsequent operation up to fine pulverization requires only 6 pieces of crushed material compared to the volume of the container 5.
This means that they will be forced to operate at a low filling rate. Moreover, during this time, it is necessary to supply power to the electromagnetic crusher to drive the working piece, which results in poor utilization of the crusher and lowers throughput. Furthermore, if the crushed material 6 is continuously crushed until it reaches the desired fine particle size, a part of the crushed material will be over-pulverized, and the resulting ultra-fine powder will act as a buffer material and inhibit impact crushing. , which rapidly reduces the overall grinding efficiency and causes increased loss of grinding energy.

This invention has been made in consideration of the above points, and its purpose is to solve the problems encountered when pulverizing crushed materials such as rice husks using the electromagnetic crusher described above, and to improve the processing capacity of crushed materials. An object of the present invention is to provide an electromagnetic pulverization device that improves pulverization efficiency.

According to the present invention, the processing container is equipped with a crushed material inlet and a crushed material outlet, the inlet is equipped with a screen to prevent the working pieces from flying out, and the outlet is equipped with a sieve having a classification function. A pneumatic conveyance-type crushed material supply path is connected to the crushed material inlet, and the crushed material is continuously supplied and discharged on the conveying airflow that ventilates into the processing container through the crushed material supply path. achieved by doing.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 4, reference numeral 10 is the electromagnetic crusher shown in FIG. 3, and the opposing left and right end surfaces of the processing container 5 are opened, and one of them is used as a crushed material inlet 11 and the other as a crushed material outlet 12. At the same time, a screen 1 is installed at the entrance 11 to prevent the working piece 7 from flying out.
3, each outlet 12 is equipped with a sieve 14 having a classification function whose mesh is selected according to the desired particle size. Furthermore, an air flow conveyance type crushed material supply path 16 is connected to the crushed material inlet 11 and connected to the crushed material hopper 15 . A fan 17 is installed on the inlet side of the supply path 16 in parallel with the hopper 15, and the operation of the fan 17 supplies air to the supply path 16.
Air is blown to the processing container 5 through the processing container 6 .

Next, the crushing operation of the above device will be described. When the electromagnetic crusher 10 and the fan 17 are in operation, if the broken material 6 such as rice husks is fed into the hopper 15, the broken material 6 will first be carried by the conveying airflow shown by the dotted arrow A, and the broken material 6 will move as shown by the solid arrow B. It is forcibly fed into the processing container 5, where it is pulverized by the random movement of the working piece 7. Then, the process progresses from coarse pulverization to fine pulverization, and when a part of the pulverized material 6 is pulverized to the desired particle size, this fine powder rides on the conveying airflow A, passes through the classification sieve 14, and is processed as shown by arrow C. It is floated and discharged to the outside of the container 5, and thus a crushed product 18 is obtained. Moreover, the above-mentioned crushing operation proceeds continuously.

By appropriately determining the pushing air pressure and air volume of the conveying airflow, even if the bulk of the crushed material 6, such as rice husks with a small bulk density, decreases as the crushing operation in the processing container progresses, this bulk can be reduced. Since the amount of crushed material 6 corresponding to the decrease in the amount of crushed material 6 is newly fed into the processing container 5 and replenished, the crushed material filling rate in the processing container can always be kept at an appropriate level and operation with good operational efficiency can be performed. In addition, the finely ground powder quickly passes through the sieve 14 and is discharged to the outside, so there is less chance of over-grinding, and therefore a crushed product 18 with a uniform particle size can be obtained. Since the proportion of ultrafine powder mixed in is reduced, high pulverization efficiency can be maintained without the risk of hindrance to the continuation of pulverization. Naturally, it is also possible to save the crushing energy consumed in excessive crushing, and hence the power consumption in the moving magnetic field generators 8 and 9.

As described above, according to the present invention, it is possible to perform continuous pulverization of granules with high operating efficiency and high pulverizing efficiency, and overall, the operating efficiency and energy saving effects are high, and moreover, particle size is uniform. It is possible to provide an electromagnetic crushing device with excellent performance for obtaining crushed products.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the configuration of a conventional mechanical crusher, Figure 2 is a diagram of the configuration principle of an electromagnetic crusher, and Figure 3 is a cross-sectional view of the configuration of a conventional mechanical crusher.
FIG. 4 is a cross-sectional view taken in the direction of arrows in the figure, and is a schematic configuration diagram of an embodiment of the present invention. 5: Processing container, 6: Crushed material, 7: Working piece, 8, 9: Moving magnetic field generator, 10: Electromagnetic crusher, 11: Crushed material inlet, 12: Crushed material outlet, 1
3: Screen, 14: Sieve, 15: Crushed material input hopper, 16: Air flow conveyance type crushed material supply path, 17: Fan, 18: Crushed material.

Claims (1)

[Claims] 1. Particles are fed into a processing container containing a large number of working pieces made of magnetic or non-magnetic conductive materials, and a moving magnetic field is applied to the processing container from the outside to prevent interaction with the moving magnetic field. In an electromagnetic crushing device that uses electromagnetic force to generate random motion in a working piece to crush crushed material, the processing container is provided with a crushed material inlet and a crushed material outlet, and a screen is installed at the inlet to prevent the working piece from flying out. Each outlet is equipped with a sieve with a classification function, and an air flow conveyance type crushed material supply path is connected to the crushed material inlet, and the conveying airflow is passed through the crushed material supply path to the processing container. 1. An electromagnetic pulverization processing device, characterized in that the pulverized material is continuously supplied and the pulverized material is discharged.