JPS6157064B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a horizontal cyclone that aims to reduce pressure loss while maintaining dust collection efficiency practically equivalent to that of a conventional vertical cyclone.

Conventional vertical cyclones that aim to reduce pressure loss include, for example, an axial flow type, an eccentric type, a swirling flow exhaust gas type, and a spiral introduction type.

Moreover, in contrast to these vertical cyclones, horizontal cyclones are used for the purpose of further downsizing the cyclone and reducing pressure loss.

In this horizontal cyclone, a hollow cone shaped like a rectangular pyramid with a downward convergence is connected to the lower part of a cylinder having a horizontal axis, and the inner wall along the connection part A rotating guide plate, a collecting guide, etc. are installed in the dust filter to prevent the dust separation efficiency from decreasing.

However, when this conventional horizontal cyclone is connected to a calcining furnace, for example as the lowest cyclone of a suspension preheater attached to a cement raw material firing device, it comes into contact with high-temperature dust-containing gas.
It is undesirable to attach something such as a guide plate inside the cyclone because it may cause damage or coaching trouble.

The present invention provides a horizontal cyclone that eliminates the above-described drawbacks of the conventional cyclone and can reduce pressure loss while maintaining dust collection efficiency equivalent to that of the conventional cyclone.

Next, embodiments of the invention will be described in detail with reference to the drawings.

1 to 3 show the case where the cyclone body has a truncated conical shape.

The body 1 of the cyclone has a hollow truncated cone shape with a pivot axis in the horizontal direction.

The small diameter part end face 2 connects the dust-containing gas inlet duct 3 to the second
Connect tangentially as shown.

On the other hand, the large-diameter end face 4 circumscribes an inverted triangular dust collecting groove 5 on its circumference.

A duct discharge chute 6 is connected to the tip of the dust collecting groove 5.

The gas exhaust duct 7 is taken out from an appropriate position on a vertical line passing through the center line of the large diameter end face 4.

The exhaust gas suction port of the gas exhaust duct 7 is made to protrude from the large-diameter end face 4 into the interior of the body 1 by an appropriate length. (This protrusion is designated by reference numeral 8.) The dust-containing gas enters the inside of the body 1 from the dust-containing gas inlet duct 3 via the small diameter end face 2. At the same time as the dust-containing gas enters, it travels toward the large-diameter end face 4 while turning along the enlarged conical inner wall of the body 1.

In this process of advancement, the swirling force from the expanding conical wall effectively acts on the separation of the duct from the gas and the advancement of the duct as a centrifugal force and an axial force.

Moreover, even if the angle of the downward slope that the bottom of the body 1 makes with the horizontal axis is set to be equal to or less than the angle of repose of the dust, the dust smoothly flows out toward the outlet end without accumulating in the body.

The separated ducts gather in the dust collection groove 5, settle down, and are discharged from the dust discharge chute 6.

Further, the gas separated from the duct is discharged from the gas exhaust duct 7.

4 to 6 show another embodiment of the present invention in which the body of the cyclone has an irregular truncated conical shape.

In this embodiment, as shown in FIG.
The center level of (diameter is D) is D-d/2
, so that the upper part of fuselage 1 is horizontal.

Therefore, the angle α that the lower part of the fuselage 1 makes with the horizontal axis is
Compared with the embodiment shown in FIGS. 1 to 3, the diameter of the large diameter portion can be relatively reduced, resulting in a more compact structure.

Furthermore, the installation position of the dust-containing gas inlet duct 3 of the horizontal cyclone of the present invention is as shown in FIG. It can be connected in any direction of 360° along the circumference and the effect remains the same. (ψ is the mounting angle) Fig. 8 shows the truncated conical overlapping type shown in Figs. 1 to 3, and Fig. 9 shows the truncated irregular cone shown in Figs. 4 to 6. Each shows the polymerization type of the shape.

That is, the small diameter portion end surfaces 2 are joined together to form a symmetrical shape.

1 is a body, 3 is a dust-containing gas inlet duct, 4 is an end face of a large diameter part, 5 is an inverted triangular dust collection groove, 6 is a dust exhaust chute, 7 is a gas exhaust duct, and 8 is inside the body of the gas exhaust duct It is a prominent protrusion.

The dust-containing gas inlet duct 3 can be installed in any direction within 360 degrees along the circumference of the small diameter portion of the body 1.

In this embodiment, one of both dust-containing gas inlet ducts 3 is provided in the center of the body 1, so the dust-containing gas enters the inside of the body 1 through a smaller diameter part than the dust-containing gas inlet duct 3, and expands left and right. It advances toward the large-diameter end face 4 while turning along the inner wall of the cone.

As shown in FIG. 10, a partition wall 9 is provided at the joint of the end face of the small diameter part, and two dust-containing gas inlet ducts 3 are installed, each sandwiching the partition wall 9 in the tangential direction of both small diameter parts. Connect to.

Experimental examples of dust collection efficiency (η%) and pressure loss (△PmmAq) when using the horizontal cyclone of the present invention (indicated by symbols H ₁ and H ₂ ) and experimental examples of conventional vertical cyclones (indicated by V symbol). 11 and 12 for comparison.

Note that the horizontal cyclone of the present invention has a truncated irregular conical shape. In addition, conventional vertical cyclones
A 180° Linden mold was used.

In addition, the dimensional ratios of each part constituting the horizontal cyclone are as follows.

When the diameter of the end face of the small diameter part is d, the diameter D of the end face of the large diameter part is 2.0 d, the horizontal length L of the conical part is 1.0 d, and the width W of the dust collection groove is 0.25 d.

Also, the length of the protrusion 8 of the gas exhaust duct 7 =
The case of 0.25d is shown by H ₁ symbol in the figure, and the case of = 0.75d is shown by H ₂ symbol.

Note that the horizontal axes in both figures indicate the duct concentration M.

In addition, as an experimental duct, a silica-alumina powder with a particle size of 44μ and a residue on the sieve of 5% was used.

The flow velocity at the cyclone inlet was 15 m/sec.

As a result of the above experiments, in Fig. 11, the horizontal cyclone of the present invention has practically the same dust collection efficiency as the conventional vertical cyclone, but the
The pressure loss shown in the figure is gradually smaller in the case of the horizontal cyclone of the present invention than in the conventional one.

Furthermore, experiments have confirmed that even if the flow velocity at the cyclone inlet is slowed down, there is almost no decrease in dust collection efficiency, but the pressure loss is significantly reduced.

The horizontal cyclone of the present invention is widely used in various applications, and one example of its application is as shown in Figures 13 and 14, where it is applied to the suspension preheater section of a rotary kiln equipped with a floating preheater for cement production. Shown below. Figure 13 is a front view, Figure 14
The figure is a sectional view taken along the line EE in FIG. 13.

In this figure, the exhaust gas g from the rotary kiln 11 is distributed to the kiln bottom hood 12, the calcining furnace 13, the lower cyclone inlet duct 14, the lower cyclone 15, the lower cyclone outlet duct 16, and the middle and lower cyclones 1.
7. Middle and lower cyclone outlet duct 18, middle and upper cyclone 19, middle and upper cyclone outlet duct 2
0, passes through the upper cyclone 21 and the upper cyclone outlet duct 22 in order, is sucked into an attraction fan (not shown), and is discharged out of the system.

On the other hand, the raw material m sent to the middle and upper stage cyclone outlet duct 20 is transferred to the upper stage cyclone 21, the upper stage cyclone chute 23, the middle and lower stage cyclone outlet duct 18, the middle and upper stage cyclone 19, the middle and upper stage cyclone chute 24, and the lower stage cyclone outlet duct. 16, the middle and lower cyclones 17, the middle and lower cyclone chute 25, the calcining furnace 13, the lower cyclone inlet duct 14, the lower cyclone 15 and the lower cyclone chute 26, and then enter the kiln bottom hood 12. During this time, the raw material m and the exhaust gas g exchange heat and are preheated and calcined.

The calciner 13 is supplied with secondary air a and fuel f from a clinker cooler (not shown) at appropriate positions along its length.

The horizontal cyclone according to the present invention includes lower stage, middle lower stage, middle upper stage, and upper stage cyclones 15, 17, 1.
Although it can be installed in either 9 or 21, in this application example, a truncated conical cyclone is used.

In particular, the horizontal cyclone of the present invention is suitable for high-temperature dust-containing gas. , the dust-containing gas duct can be connected in any direction. , the height can be reduced. Taking advantage of this feature, as shown in FIG. 14, the high-temperature dust-containing gas from the calciner 13 is connected to the lower cyclone inlet duct 14 through a downward straight pipe duct, thereby lowering the installation level of the lower cyclone 15.

Another feature is that by using the horizontal polymerization type cyclone of the present invention as the lower cyclone 15, the preheating area can be divided into two systems with a compact space volume.

As mentioned above, the suspension and
This is an example of application to a preheater section. This has the advantage of reducing overall pressure loss and making effective use of the entire system structure.

In addition, it can be widely used as a dust collection cyclone in general pollution prevention equipment, powder sorting equipment, etc.

Since the present invention is configured as described above and operated as described above, the following effects can be achieved.

(1) The cross-sectional shape perpendicular to the horizontal axis of the fuselage is always circular and expands from the dust-containing gas inlet end to the outlet end, and the line that passes through the bottom slopes downward. .

For this reason, the dust-containing gas moves in a spiral shape while expanding its radius of gyration, and its speed gradually decreases. In this process, the axial component of the swirling force effectively acts on the dust centrifuged from the gas and moving forward, causing a smooth flow toward the outlet end without the duct accumulating at the bottom of the body 1.

Furthermore, the fact that the cross section is circular over the entire length of the fuselage does not cause any disturbance in the centrifugal action and reduces the rate of re-scattering of the separated dust.

Furthermore, since the body is expanded and has a conical shape, the introduced gas immediately changes its direction in a spiral shape and advances even at the connection part of the dust-containing gas inlet duct 3, and after one turn, it deviates from the flow path of the introduced gas, and the gas Disturbances caused by mutual interference are reduced. Moreover, the flow of gas and dust inside the fuselage 1 is unidirectional from the small diameter part to the large diameter part of the truncated cone, so there is a loss due to gas reversal, unlike in a conventional vertical cyclone. There is no.

As described above, by creating a structure that reduces gas flow turbulence and does not impair centrifugal action, a cyclone that can reduce pressure loss with high dust collection efficiency can be obtained, and has an energy saving effect. I can give it to you.

(2) Since the cross-sectional shape of the fuselage 1 perpendicular to the horizontal axis is circular, dust is effectively separated.

Therefore, there is no need to provide a guide plate or the like inside the fuselage. This not only simplifies the structure, but also makes it easy to connect to the calciner outlet, for example.
There is no problem of damage caused by high-temperature dust-containing gas, and
Since coaching problems caused by attachments inside the fuselage are not caused, it is more maintenance-free and can be used in a wider range of applications.

(3) Since the pivot axis of the body 1 is horizontal and has a truncated conical shape, the dust-containing gas inlet duct 3 can be connected in any direction of 360° in the circumferential direction on the small diameter side of the end face of the body 1.

Therefore, the dust-containing gas inlet duct 3 itself can be provided with a straight pipe without providing a curved pipe section. Therefore, the pressure loss at the bend can be reduced, and the degree of freedom in vertical and horizontal relationships with respect to the pivot axis is increased.
A more effective arrangement can be made for cyclone installation.

In addition, unlike conventional vertical cyclones, there is no need to provide a horizontal section in the dust-containing gas inlet duct.
There is no risk of trouble caused by dust accumulation on horizontal areas. Therefore, the gas flow rate to the dust-containing gas inlet duct 3 can be slowed down, which is also effective in reducing pressure loss within the pipe.

(4) Since the pivot axis of the fuselage 1 is horizontal and has a truncated conical shape, dust can be separated easily. Therefore, the horizontal length of the body can be shortened, and the volume can be reduced compared to conventional vertical cyclones.

Furthermore, when used as the polymerization type shown in FIGS. 8 and 9, space can be used even more effectively and equipment costs can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of the horizontal cyclone of the present invention (truncated conical shape), Fig. 2 is a view taken from A-A in Fig. 1, and Fig. 3 is a view taken from B-B in Fig. 1. figure,
FIG. 4 shows another embodiment of the present invention (truncated irregular conical shape)
5 is a front view of the
6 is a view taken from the line DD in FIG. 4, FIG. 7 is an explanatory diagram of the installation direction of the dust-containing gas inlet duct, and FIG. ), FIG. 9 is a front view (partial cross-section) of another embodiment of the present invention (overlapping type of irregular truncated cone), and FIG. 10 is an application example of FIG. 8. It is. 11th
The figure and FIG. 12 are diagrams comparing experimental results between the horizontal cyclone of the present invention and a conventional vertical cyclone. FIG. 11 shows the relationship between dust concentration and dust collection efficiency, and FIG. 12 shows the relationship between dust concentration and pressure loss. FIG. 13 is a schematic configuration diagram of an embodiment in which the horizontal cyclone of the present invention is applied to the suspension preheater section of a rotary kiln with a floating preheating device for cement production.
The figure shows a sectional view taken along line EE in FIG. 1 is the body of the cyclone, 2 is the end face of the small diameter part, 3 is the dust-containing gas inlet duct, 4 is the end face of the large diameter part, 5 is the dust collection groove, 6 is the dust discharge chute, 7 is the gas discharge duct, and 8 is the gas discharge duct. 9 is a partition wall,
11 is a rotary kiln, 12 is a rotary kiln bottom hood, 13 is a calcining furnace, 14 is a lower cyclone inlet duct, 15 is a lower cyclone, 16 is a lower cyclone outlet duct, 17 is a middle and lower cyclone, and 18 is an middle and lower cyclone outlet ducts, 19 is a middle and upper stage cyclone, 20 is a middle and upper stage cyclone outlet duct, 21 is an upper stage cyclone, 22 is an upper stage cyclone outlet duct, m indicates the flow of raw material, and g indicates the flow of exhaust gas.

Claims (1)

[Scope of Claims] 1. A dust-containing gas inlet duct is tangentially connected to the end face of the small diameter part of the hollow truncated conical body with a pivot axis in the horizontal direction. An inverted triangular dust collection groove is circumscribed on the inside, a dust exhaust chute is connected to the tip of the dust collection groove, and the exhaust gas inlet of the gas exhaust duct is made to protrude an appropriate length into the body from the end face of the large diameter part. A horizontal cyclone featuring 2. The horizontal cyclone according to claim 1, wherein the center level of the end face of the large diameter part is lower than the center of the end face of the small diameter part, so that the upper end face of the body is horizontal. 3. The horizontal cyclone according to claim 1 or 2, characterized in that the end faces of the small diameter portions are joined to face each other and a dust-containing gas inlet duct is provided in the center of both small diameter portions. 4. The end surfaces of the small diameter portions are joined to face each other, a partition wall is provided at the joint of the end surfaces of the small diameter portions, and a dust-containing gas inlet duct is provided in the tangential direction of both small diameter portions, sandwiching the partition wall. A horizontal cyclone according to claim 1 or 2. 5. The horizontal cyclone according to claim 1, 2 or 3, wherein the dust-containing gas inlet duct is provided at an arbitrary position along the circumference of the end face of the small diameter portion in a tangential direction.