JPH0244859Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a secondary separation chamber of a gas cyclone device.

[Conventional technology]

A gas cyclone device is known as a device in which a gas containing solid fine particles flows into a cyclone body in a spiral shape, and the solid fine particles are separated and collected by centrifugal force acting on the circulating flow.

In order to improve the separation and collection efficiency of such conventional gas cyclone equipment, the inventor of this application
We have already proposed a gas cyclone device according to Publication No. 2053. The gas cyclone device according to this publication is
A cylindrical cyclone main body having a conical part connected to a discharge port for collecting powder, etc. at the lower end, a collection pipe connected to window holes provided at appropriate intervals in the straight body of the main body, A common chamber is provided to connect the lower end of the tube and the outlet at the lower end of the cyclone body.

In this case, part of the processing gas is contained in the main body, collection tube,
The fluid flows as follows due to the pressure difference inside the chamber. That is, it is recycled in the following order: outer wall of the main body → collection tube → chamber → center of the main body. This gas is called "recycled gas".

[Problem that the invention attempts to solve]

In a conventional gas cyclone device with such a configuration,
In the chamber, powder [solid] that is easily affected by the gas flow, that is, fine powder with a light specific gravity and a highly uneven surface, is removed when the recycled gas flows [rises] from the chamber to the center of the main body. It is secondarily mixed into this recycled gas, moves to the negative pressure section in the center of the main body, and is discharged along with the exhaust gas. This rate of contamination varies depending on the type of powder, but the lighter the specific gravity or the more uneven the surface, the higher the rate of secondary contamination. Therefore, depending on the type of powder, specific gravity, etc., the gas cyclone apparatus still has the disadvantage that it may not be possible to completely collect and separate these powders.

This idea was made in view of the current situation, and its purpose was to provide a secondary separation chamber below the gas cyclone device, and to provide a slit in this separation chamber to collect the gas once collected. The objective is to prevent secondary contamination of powder, and also to prevent powder descending from the main body through the conical portion from being mixed into the recycled gas, thereby improving separation and collection efficiency.

[Means for solving problems]

As a means to solve the above problems, this invention includes an inner cylinder whose upper end is connected to the lower end of the lower conical part of the main body of the gas cyclone, an outer cylinder that surrounds this inner cylinder and has a discharge port at its lower end, and an outer cylinder that surrounds this inner cylinder and has a discharge port at its lower end. The secondary separation chamber is equipped with a collection tube introduced at an appropriate position in the upper part of the cylinder, and slits are provided along the axial direction at appropriate intervals in the circumferential direction of the inner cylinder.

[Effect]

Exhaust gas flowing in from the inlet at the top of the main body of the gas cyclone device is rotated within the main body, turns into a vortex, descends, rises from the exhaust pipe in the center of the main body, and is discharged. During the descent of the exhaust gas, the fine powder contained in the exhaust gas moves from the center of the main body to the peripheral wall due to the centrifugal action caused by the vortex, and descends along the wall of the high-pressure gas flow circulating near the peripheral wall. At the same time, a part of it descends through a window hole provided in the outer peripheral wall and passes through a collection tube.

In the secondary separation chamber connected to the lower part of the cyclone device main body, the recycled gas from the collection tube collects in the center of the chamber according to the balance of internal pressure, and then passes through the chamber inner cylinder again to the cyclone. It rises to the upper discharge pipe of the main body of the device. When moving such recycled gas,
The inner cylinder of the chamber is provided with a slit of an appropriate shape along its axial direction, so when the inner cylinder is rotated up and down, the fine powder contained in the recycled gas is moved to the center by the centrifugal action. The material that has moved from the section to the peripheral wall section passes through this slit and is returned into the secondary separation chamber. At the same time, the collected fine powder that descends along the inner circumferential wall of the conical portion at the bottom of the cyclone main body is also separated from the slit into the secondary separation chamber.

〔Example〕

Embodiments of this invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is an overall schematic diagram of a cyclone device having a secondary separation chamber of this invention. 1 is a cyclone main body, 2 is an inlet, 3 is a straight body part, 4 is a conical part, 5 is an exhaust pipe, 6 is a window hole, 7 is a collection pipe,
Except for the secondary separation chamber 10 provided at the bottom of the cyclone main body 1, these are almost the same as those of the above-mentioned Utility Model 57-
The structure is similar to that of Publication No. 2053.

The gas containing fine particles flowing into the inlet 2 of the cyclone body 1 flows into the straight body part 3 at a constant speed in the tangential direction thereof, and gradually rotates along the circumferential walls of the straight body part 3 and the conical part 4. descend. The fine particles contained in the swirling of the gas are carried toward the peripheral wall by the action of centrifugal force, and gradually lose kinetic energy due to collision and friction with the peripheral wall, and are moved from the straight body part 3 to the conical part 4. Falling down in a spiral. On the other hand, the gas from which the particles have been separated is discharged from the exhaust pipe 5.

Furthermore, while the swirling flow is swirling around the inner circumference of the straight body part 3,
Since the pressure is low in the window holes 6 provided at appropriate intervals on the inner wall, the particles moving toward the inner wall pass through the pressure wall due to the swirling flow layer generated along the inner wall. Then, it descends through the window hole 6 through the collection tube 7.

The highly concentrated air stream containing fine particles flowing out from the cyclone device main body to the collection tube 7 is further subjected to secondary separation in the following secondary separation chamber.

FIG. 3 is a main sectional view of an embodiment of the secondary separation chamber of the gas cyclone device according to the present invention.

This secondary separation chamber 10 has an outer cylindrical portion 11
It has a conical part 12 below it, a discharge port 13 at its lower end, and an inner cylindrical part 15 that passes through a top plate 14 above the chamber and connects to the lower end of the straight body part 3 of the cyclone device main body.

A collecting pipe 7 extending downward from the upper part of the cyclone apparatus main body is inserted into the top plate 14.

FIG. 5 is an enlarged perspective view of the inner cylinder portion 15,
A plurality of slits 16 are provided in the inner cylindrical portion 15 at appropriate intervals along the axial direction, and the slits 16 are arranged in multiple rows (in this embodiment, slits 16 are arranged at appropriate intervals on the circumference of the inner cylindrical portion 15). column) is provided. Also,
In principle, the shape of each slit, the installation angle with respect to the axial direction, etc. should be such that it does not adversely affect the swirling flow of gas when separating powder particles by centrifugal force.In this example, the rectangular slit is The hole is shown diagonally perforated at an appropriate angle.

Next, its effect will be explained.

As described above, the fine powder particles separated in the cyclone device main body above the secondary separation chamber 10 descend along the inner peripheral wall of the cyclone device main body and reach the inner peripheral wall of the inner cylindrical portion 15. The fine powder particles that have passed through pass through the collection tube 7 and similarly reach the secondary chamber.

By the way, the gas pressure inside the secondary separation chamber is
The regions corresponding to the symbols , , , shown in FIG. 3 are distributed in the order of >>>.
The pressure is the highest due to the centrifugal force caused by the swirling flow inside the cyclone device body, the pressure is the next highest near the peripheral wall in the secondary separation chamber, followed by the central part.

Due to such pressure distribution, a portion of the processing gas flows as follows.

External wall of cyclone device main body → Collection pipe → Secondary separation chamber → Center of main body Because of this flow of recycled gas, when the recycled gas flows (rises) from inside the secondary separation chamber to the center of the main body, The collected fine powder may be entrained in the recycle gas and become secondarily mixed into the main gas stream. This secondary contamination rate varies depending on the type of powder, but it is higher when the specific gravity of the powder is lighter and the surface shape is more uneven.
Further, powder falling along the peripheral wall of the conical portion of the cyclone device body may also be mixed into the recycled gas.

Therefore, in this embodiment, secondary contamination of the fine powder is prevented by the slit 16 provided in the inner cylindrical portion 15 in the following manner. That is, although the flow of the recycle gas is substantially the same as described above, the provision of the slit 16 changes a portion of the flow. Although the pressure near the inner cylinder portion 15 is still the highest, the provision of the slit 16 reduces the pressure locally at that portion. Therefore,
The fine powder mixed in the recycle gas is carried to the peripheral wall of the inner cylinder part 15 by the centrifugal force caused by the swirling flow of the recycle gas when rising inside the inner cylinder part 15,
Since the pressure wall existing nearby has been partially ruptured by the pressure drop, it passes through the slit 16 and is recycled back into the secondary separation chamber.

Further, the fine powder that descends along the inner circumferential wall of the conical portion 4 at the bottom of the cyclone main body is similarly discharged from the slit 16 into the secondary separation chamber. Therefore, secondary contamination with the recycled gas is prevented.

〔effect〕

As detailed above, in the secondary separation chamber according to this invention, slits are provided in the inner cylinder part at an appropriate interval and number within a range that does not adversely affect the flow of recycled gas, thereby preventing secondary separation into recycled gas. The structure is configured to perform secondary separation of fine powder and at the same time discharge the fine powder falling along the circumferential wall of the conical part of the cyclone device body from the slit into the secondary separation chamber. It is possible to prevent secondary contamination of the collected powder and also to prevent the powder descending from the conical portion from being mixed into the recycled gas, thereby further increasing the separation and collection efficiency.

[Brief explanation of drawings]

Figure 1 is an overall schematic diagram of a gas cyclone device equipped with a secondary separation chamber according to this invention;
The figure is a sectional view taken from the line -, Figure 3 is a main sectional view of the secondary separation chamber of this invention, Figure 4 is a sectional view taken from the line -, and Figure 5 is a partially enlarged perspective view of the inner cylinder. It is. 4... Cone part, 7... Collection tube, 10... Chamber for secondary separation, 11... Outer cylinder part, 12... Cone part, 13... Outlet, 15... Inner cylinder part.

Claims (1)

[Claims for Utility Model Registration] (1) An inner cylinder whose upper end is connected to the lower end of the lower conical part of the main body of the gas cyclone, an outer cylinder surrounding this inner cylinder and having a discharge port at its lower end, and an upper part of the outer cylinder. 1. A secondary separation chamber for a gas cyclone device, comprising a collection tube introduced at an appropriate position, and slits are provided along the axial direction of the inner cylinder at appropriate intervals in the circumferential direction of the inner cylinder. (2) The secondary separation chamber for a gas cyclone device according to claim 1, wherein the slit is rectangular and is provided obliquely with respect to the axial direction of the inner cylinder.