JPS6334785B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cyclone, and more specifically,
The present invention relates to a vertical cyclone with low pressure loss, no dust accumulation or coating, and low dust concentration in the gas discharged from the cyclone, that is, with good separation efficiency.

Vertical cyclones use centrifugal force to separate and collect dust in gas, and are often used in preheating devices for cement raw materials, etc., and have the structure shown in Figures 1 and 2. ing.

That is, the conventional cyclone 1 has a cylindrical body 2 and an inverted conical hopper 3 connected to the lower end thereof, and a rectangular gas is tangentially and horizontally connected to the upper part of the cylindrical body 2. An introduction duct 4 is provided. As shown in FIG. 1, the outer wall 4a of the gas introduction duct 4 is provided so as to extend beyond the outer wall of the cylindrical body 2. Further, a gas exhaust pipe 5 is provided on the upper lid portion 2a (see FIG. 2) of the cylindrical body 2, and a dust exhaust pipe 6 is provided on the lower end of the inverted conical hopper 3.

Based on this structure, the dust-containing gas introduced from the gas introduction duct 4 is subjected to a classification action by the swirling flow inside the cyclone, and the heavy dust in the dust-containing gas is subjected to centrifugal force to form a cylinder. The dust separates into the shaped body 2 and the peripheral wall of the inverted conical hopper 3, flows down to the lower part of the inverted conical hopper 3 by gravity, and is discharged from the dust discharge pipe 6.

On the other hand, gas with a light mass descends through the inside of the swirling flow, reverses itself near the lower end of the inverted conical hopper, and is discharged from the gas exhaust pipe 5 while swirling upward.

When such a structure is adopted, when the dust-containing gas introduced into the cyclone from the gas introduction duct 4 is given a swirling flow, separation of gas and dust starts due to centrifugal force.

Then, the dust separates and moves to the peripheral wall of the cylindrical body 2 and the peripheral wall of the inverted conical hopper 3, but the outer wall 4a of the rectangular gas introduction duct 4 is made to protrude beyond the outer wall of the cylindrical body 2. established,
Since the bottom surface 4b of the gas introduction duct 4 is horizontal, the dust separated into this part is not only prevented from flowing further downstream to the cylindrical body 2 and the peripheral wall of the inverted conical hopper 3; Dust accumulates on the protruding bottom surface of the gas introduction duct 4.

This accumulated dust disturbs the flow of the dust-containing gas flowing down, and in some cases, the accumulated dust in this portion may be taken along with it and short-passed into the gas exhaust pipe.

Further, the dust-containing gas introduced through the horizontal gas introduction duct 4 has a strong horizontal swirling flow as the overhanging part of the gas introduction duct serves as a guide path.
This causes obstruction to the movement of dust to the lower end of the cyclone, increases the amount of dust remaining in the cyclone, and increases the number of turns of the gas flow within the cyclone, which causes the dust to be discharged from the gas exhaust pipe 5. The amount of dust was large and the pressure loss was also high.

In addition, the confluence part (first
In part 2b of the figure), the pressure loss increases due to the collision and merging, and turbulence occurs in the dust-containing gas flow, and this dust-containing gas short-passes to the gas exhaust pipe 5, causing an increase in the dust concentration in the exhaust gas. It was becoming.

Further, the lower end of the cylindrical body 2 and the upper end of the inverted conical hopper 3 are connected to each other so that their diameters are equal.
Therefore, this connecting portion 3a is connected to the cylindrical body 2.
It consists of a vertical side wall of the inverted conical hopper 3 and an inclined side wall of the inverted conical hopper 3. In that configuration, there is an abrupt change in angle, and the abrupt angular change is on the same horizontal plane.

Therefore, the dust that has flowed down from above the side wall portion of the cylindrical body 2 flows down in a manner that crosses this abrupt angle change portion. At that time, the dust was disturbed by the swirling and descending gas flow at the part where the angle suddenly changed, and a phenomenon occurred in which the dust that had been separated once was re-splattered.

The present invention was made to eliminate the above-mentioned conventional drawbacks, and aims to provide a cyclone with low pressure loss, no dust accumulation inside the cyclone, and low dust concentration in exhaust gas. That is.

Hereinafter, embodiments of the present invention will be described together with examples of devices used in the process leading to the present invention.

FIGS. 3, 4, and 5 are a first example of an apparatus showing a cyclone in the process leading to the present invention, and FIGS. 6 and 7 are a second example of the apparatus similarly showing a cyclone in the process leading to the present invention. , FIGS. 8 and 9 show a third example of a cyclone in the process of achieving the present invention, and FIGS. 10 and 11 show an embodiment of the cyclone of the present invention.

First, a first example of an apparatus showing a cyclone in the process leading to the present invention will be described based on FIGS. 3, 4, and 5. In each figure, the same parts as in FIGS. 1 and 2 are designated by the same reference numerals, and their explanations will be omitted.

In this first device example, one end of the vertical side wall of the spiral body 2 intersects the outer wall 4a of the rectangular gas introduction duct 4 in a tangential manner, and this part has the maximum radius, and the other end By gradually decreasing the radius and gradually lengthening the vertical side wall, a spiral body 2 is formed, with the minimum radius corresponding to the vertical extension line of the inner wall 4c of the gas introduction duct 4. The lower end of the vertical side wall of the shaped body 2 is connected to the upper end 3a of the inclined side wall of the inverted conical hopper 3.

Note that the bottom surface 4d of the connecting portion between the rectangular gas introduction duct 4 and the spiral body 2 (A, in FIG. 5)
In order to reduce the accumulation of dust in the dust-containing gas introduced from the gas introduction duct 4, the part surrounded by B and C) has one end connected to the horizontal bottom surfaces A and C of the gas introduction duct, and the other end arranged in a spiral shape. It is inclined so as to coincide with the vertical lower end B of the minimum radius portion of the fuselage 2.

Since this first device example is configured as described above, the bottom surface 4b of the gas introduction duct 4 does not have a bottom surface after the connection with the spiral body 2, and therefore, unlike the conventional case, , there is no dust accumulation in this area and no short path for the accumulated dust.

Further, the protruding portion of the gas introduction duct does not form a guiding path for dust-containing gas, and the dust flows down smoothly.

In addition, the side wall of the spiral body 2 and the inverted conical hopper 3
As is clear from FIGS. 4 and 5, the connecting portions 3a of the side walls are not on the same horizontal plane, but have a gently sloping helical shape.

Therefore, the dust that has flowed down to this part is not disturbed by the swirling downward flow of gas in the cyclone, and flows down along the swirling downward flow of the cyclone peripheral wall, and the dust flows down the vertical direction of the spiral body 2. connection part 3 between the side wall and the inclined side wall of the inverted conical hopper 3
It is less affected by sudden changes in the angle of a, and flows smoothly along this connecting part 3a,
The dust is discharged from the dust discharge pipe 6.

Further, the end of the spiral body 2 is connected to the inner wall of the gas introduction duct 4 on a vertical extension thereof, and is formed so that its radius is minimized.

Therefore, the dust-containing gas flow introduced from the gas introduction duct 4 and the swirling flow within the cyclone merge in a substantially parallel manner, resulting in a significant collision and confluence as shown in the conventional case shown in section 2b in FIG. is relaxed, thereby reducing the pressure loss.Furthermore, the vertical side wall of the spiral body 2 in this part is
Since the vertical side wall of the conventional cyclone shown in FIG. It is carried out quickly and the separation of gas and dust is good. Furthermore, the number of turns of the gas swirling downward also decreases, and the pressure loss also decreases.

Next, the second stage of the cyclone in the process leading to the present invention will be explained.
An example of the apparatus will be explained based on FIGS. 6 and 7.

The difference between the first device example and this second device example is that the vertical side wall of the spiral body 2 and the inclined side wall of the inverted conical hopper 3 are arranged so that the side wall 3b has a different inclination angle.
It's because I connected it with .

By using this second device example, the total height of the cyclone can be lowered without impairing the effect of the cyclone in the first device example, so this cyclone can be used as a preheating device for firing cement raw materials. When used for such purposes, the overall height of the device can be lowered.

Further, a third example of a cyclone device in the process leading to the present invention is shown in FIGS. 8 and 9.

This third device example is a lower part 5a of the gas exhaust pipe 5 disposed in the upper lid portion 2a of the first device example described above.
, which has a boot-like shape with an egg-shaped horizontal cross section that expands in a specific range.

In this third device example, by inflating the lower part 5a of the gas exhaust pipe 5 to a specific range, the pressure loss is lowered, and the particles in the swirling gas in the upper part of the cyclone are pushed against the peripheral wall inside the body. It also creates a guiding effect, further increasing dust collection efficiency.

Next, embodiments of the present invention are shown in FIGS. 10 and 1.
This will be explained based on FIG. In each figure, the same parts as in FIGS. 3 to 9 described above are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The cyclone of the present invention is based on the first to third device examples of the cyclone in the process leading to the present invention described above, and is a cyclone that has lower pressure loss and can further improve dust collection efficiency. It is something.

That is, in the cyclone of the present invention, as shown in FIGS. 10 and 11, one end of the vertical side wall of the spiral body 2 tangentially intersects with the outer wall 4a of the rectangular gas introduction duct 4. , this part is the maximum radius, and the other end has a gradually smaller radius, and
Gas introduction duct 4 while gradually lengthening the vertical side wall
It forms a spiral body 2 whose minimum radius is a part that coincides with the vertical extension line of the inner wall 4c, and the lower end of the vertical side wall of the spiral body 2 and the upper end of the inclined side wall of the inverted conical hopper 3 are formed. and the lower part 5 of the gas exhaust pipe 5 disposed on the upper lid part 2a of the spiral body 2.
It has a boot (boot) shape with an egg-shaped horizontal cross section 5b that expands in the direction of a specific range at (a).

Note that the bottom surface 4d of the connecting portion between the rectangular gas introduction duct 4 and the spiral body 2 is connected to the gas introduction duct 4.
In order to reduce the accumulation of dust in dust-containing gas introduced from It is tilted like this.

Since the present invention is configured as described above, the bottom surface 4b of the gas introduction duct 4 does not have a bottom surface after the connection with the spiral body 2, and therefore, unlike the conventional case, the bottom surface 4b is not formed at this portion. Accumulation of dust,
There is no short path for accumulated dust.

Further, the protruding portion of the gas introduction duct does not form a guide path for dust-containing gas, and the dust flows down smoothly.

Further, the vertical side wall of the spiral body 2 and the inclined side wall of the inverted conical hopper 3 have different inclination angles.
As is clear from FIG. 11, the connecting portions 3a on both side walls are not on the same horizontal plane at the terminal end of this connecting portion, but have a gently sloping helical shape. , the total height of the cyclone can be lowered, and the height of a preheating device using this cyclone can be lowered.
The dust flowing down to a is not disturbed by the swirling downward flow of gas in the cyclone, flows smoothly down along the swirling downward flow of the cyclone peripheral wall, and is discharged from the dust discharge pipe 6.

Further, the end of the spiral body 2 is connected to the inner wall of the gas introduction duct 4 on a vertical extension thereof, and is formed so that its radius is minimized.

Therefore, the dust-containing gas flow introduced from the gas introduction duct 4 and the swirling flow within the cyclone merge in a substantially parallel manner, resulting in a significant collision and confluence as shown in the conventional case shown in section 2b in FIG. is relaxed, thereby reducing the pressure loss.Furthermore, the vertical side wall of the spiral body 2 in this part is
Since the vertical side wall of the conventional cyclone shown in FIG. It is carried out quickly and the separation of gas and dust is good. Furthermore, the number of turns of the gas swirling downward also decreases, and the pressure loss also decreases.

Furthermore, since the lower part 5a of the gas exhaust pipe 5 is expanded to a specific range, pressure loss is further reduced.
It also creates a guiding effect that pushes the particulates in the swirling gas in the upper part of the cyclone toward the peripheral wall inside the body, further increasing dust collection efficiency.

Note that FIGS. 12a and 12b show for reference the dust collection efficiency and pressure loss with respect to the mixing ratio of the first example of the apparatus in the process leading to the present invention described above.

The results for the first example device are represented by the solid line, and the results for the conventional cyclone are represented by the dashed line.

In this comparison, it is clear that the effect of the first device example is superior to that of the conventional type, and from this it is clear that the effect of the cyclone of the present invention is also equal to or better than this.

As is clear from the above description, according to the present invention, the bottom surface of the gas introduction duct is not formed on the spiral body side wall, and the dust separated and moved to this part quickly descends along the spiral body side wall. do. Further, the connection portion between the spiral body side wall and the inclined side wall of the inverted conical hopper has side walls with different inclination angles,
In addition, since a part of it forms a gentle spiral shape, the height of the cyclone can be lowered, and the dust that has flowed down to this part is further lowered by the swirling downward flow inside the cyclone. In addition, in the upper part of the cyclone, the expanded part of the lower part of the gas exhaust pipe can apply a pressing force to the particulates in the swirling gas against the inner circumferential wall of the fuselage. Discharge from the discharge pipe is performed smoothly, increasing dust collection efficiency. On the other hand, the number of turns of the swirling gas in the cyclone and the gas discharge pipe decreases, and the pressure loss also decreases.

Furthermore, collisions and merging between the dust-containing gas flow introduced from the gas introduction duct and the swirling flow are alleviated.
Pressure loss is also reduced.

[Brief explanation of drawings]

Figures 1 and 2 show the structure of a conventional cyclone. Figure 1 is a plan view, Figure 2 is a front view of Figure 1, and Figures 3, 4, and 5 are the main views. 3 is a plan view, FIG. 4 is a front view of FIG. 3, FIG. 5 is a side view of FIG. 4, and FIG. and the seventh
The figures show the structure of the second example of the device in the process leading to the present invention, FIG. 6 is a plan view, FIG. 7 is a front view of FIG. 6, and FIGS. 8 and 9 are views according to the present invention. 8 is a plan view, FIG. 9 is a front view of FIG. 8, and FIGS. 10 and 11 show the structure of an embodiment of the present invention. 10 is a plan view, FIG. 11 is a front view of FIG. 10, and FIGS. 12a and 12b are views of the cyclone of the first example of the device and the conventional cyclone in the process leading to the present invention. The experimental results are shown in which a is a diagram showing dust collection (separation) efficiency versus mixing ratio, and b is a diagram showing pressure loss versus mixing ratio. 1... cyclone, 2... fuselage, 2a... upper lid of the fuselage, 2b... gas confluence near the connection between the gas introduction duct and the spiral shaped fuselage, 3...
... Inverted conical hopper, 3a... Connection portion between the lower end of the spiral body and the upper end of the inverted conical hopper, 3b... Side wall with different inclination angle, 4... Gas introduction duct, 4a...
...outer wall of the gas introduction duct, 4b...bottom of the gas introduction duct, 4c...inner wall of the gas introduction duct,
4d...Bottom surface of the connection portion between the gas introduction duct and the spiral body, 5...Gas discharge pipe, 5a...Lower part of the gas discharge pipe, 6...Dust discharge pipe.

Claims (1)

[Claims] 1. An inverted conical hopper is formed at the bottom, a dust discharge pipe is formed at the lower end of the inverted conical hopper, a cylindrical body is disposed continuously at the upper end of the inverted conical hopper, and the cylindrical body is tangentially or circularly disposed. In a cyclone that is equipped with a gas introduction duct that introduces dust-containing gas from the circumferential direction and a gas discharge pipe on the upper lid of the cylindrical body, the vertical side wall of the cylindrical body is formed in a spiral shape, and the spiral shape One end of the vertical side wall of the body is tangent to the outer wall of the gas introduction duct to make this part the maximum radius, and the other end is connected to the vertical extension of the inner wall of the gas introduction duct to make this part the minimum radius. The lower end of the vertical side wall of the spiral body and the upper end of the inclined side wall of the inverted conical hopper are connected by side walls having different inclination angles, and the gas exhaust pipe installed in the upper lid of the spiral body is A cyclone characterized by having a boot-shaped lower part with an egg-like horizontal cross section that expands in a specific direction.