JPS60129522A - Preventive device of stack rain - Google Patents

Abstract

PURPOSE:To enable prevention of a stack rain at the size in height of the titled device of less than a half of a conventional one, by providing a zigzag waterdrop collecting plate in a cylindrical body, which is made into a passage of exhaust gas by connecting it with the upper part of a stack, in the direction of a flow of exhaust gas by partitioning the cylindrical body vertically. CONSTITUTION:The titled device is provided with a cylindrical body 12 which is made into a passage of exhaust gas by connecting with the top of a stack 10, an external cylindrical body 14 forming a space 13 opening upward between the external cylindrical body 14 and the cylindrical body 12 by covering the external circumference of said cylindrical body 12 coaxially, and a plurality of sheets of waterdrop collecting plates 15 which is partioning vertically the inside of the foregoing cylindrical body 12 and at least one side part of which is protruded within the space 13 from an opening part 12b formed on a circumferential wall of the cylindrical body 12. Then the waterdrop collecting plate 15 is formed in zigzag manner in the direction of a flow of the exhaust gas and an angle theta of inclination is given to the same. When the exhaust gas passes through the inside of a gas 28 between the waterdrop collecting plates 15, 15 adjoining to each other, a water drop which has ascended along with the exhaust gas adheres on slope parts 18, 19 of the waterdrop collecting plate 15, streamed into the space 13 as shown by a broken line and drained outside of the stack 10 through a drainage pipe 16.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stuck rain prevention device that prevents the occurrence of stuck rain by removing the upper end of a chimney.

Stuck rain occurs when the moisture in the flue gas rising inside the smoke machine condenses into water droplets on the way up, and these water droplets rise with the flue gas due to the temperature-pressure phenomenon caused by the rising action of the flue gas and scatter from the chimney to the input. This is a phenomenon in which the smoke falls like rain around the chimney.

Conventionally, a device shown in FIG. 7 has been developed as a device for preventing the stuck rain.

The trapping device causes the exhaust gas rising in the chimney to collide with a porous moisture absorbent material, thereby causing the moisture absorbent material to capture water droplets that have risen together with the exhaust gas. A porous hygroscopic material 3 attached to the inner circumference of the cylindrical body 2, a drift plate 4 that converts the flow of exhaust gas into a swirling flow in order to cause the exhaust gas to collide with the hygroscopic material 3, and a The structure includes a gutter 5 for collecting water droplets, and a discharge device 6 for discharging the water droplets collected in the gutter 5 to the outside of the chimney 1.

By the way, chimneys that require such a device are usually
The height is 10-. 200 meters long and several meters in diameter. On the other hand, in order to completely remove the water droplets that rise with the exhaust gas, the conventional device as described above requires a height dimension of approximately 6 times the chimney diameter.
In the case of 36 meters, the device height H (see Figure 1) would be as high as 36 meters. In other words, the construction of the above-mentioned apparatus required large-scale construction at a high place, which resulted in problems such as a long construction period and an extremely high construction cost.

This invention was proposed in view of the above-mentioned circumstances, and has a new configuration for the means for capturing water droplets rising with exhaust gas,
This allows the height of the equipment to be compacted to less than half that of the conventional stack rain, which reduces the construction scale and shortens the construction period and construction costs. The purpose is to obtain a preventive device.

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

FIG. 2 is a side sectional view of one embodiment of the present invention, in which 10 is an existing chimney and 11 is a stuck rain prevention device according to the present invention.

The stuck rain prevention device 11 includes a cylinder 12 which has a large diameter part 12a with a diameter larger than 1° of the chimney and is connected to the upper end of the chimney 1° and serves as a passage for exhaust gas, and an outer periphery of the cylinder 12. an outer cylindrical body 14 concentrically covering the outer cylindrical body 14 and forming a space 13 opening upwardly between the cylindrical body 12 and the large diameter portion 12a;
A plurality of water droplet collecting plates 15 partition the inside of the cylindrical body 12 vertically at positions corresponding to the cylindrical body 12 and protrude into the space 13 from an opening 12b formed in the circumferential wall of the cylindrical body 120 at least on one side. It is equipped with

The cylindrical body 12 and the external cylindrical body 14 each have their upper ends 12c and 14a constricted in the shape of a nozzle, and accelerate the passing exhaust gas by converting it into a contracted flow.

Further, a bottom plate portion 14b joined to the cylinder body 12 is provided at the lower part of the external cylinder 14, and the bottom plate portion 14b functions as the bottom of the cavity 13. And this bottom plate part 14
b is a drain pipe 16 for discharging water that has flowed into the space 13;
is provided.

As shown in FIG. 3, the plurality of water droplet collecting plates 15 are arranged in parallel to each other via a connecting plate 17 that is vertically supported within the cylinder 12 and including the central axis of the cylinder 12. is supported by That is, a plurality of water droplet collecting plates 15/fi
, are regularly arranged on both sides of the connecting plate 17 as a boundary surface, dividing the inside of the cylindrical body 12 vertically into a large number of parts.

Each water droplet collecting plate 15 prevents the exhaust gas from colliding with the slope.
Therefore, the water droplets that rise with the exhaust gas are captured, and as shown in Fig. The zigzaku -shaped direction is made in the direction of the flow, and the bottom and the slope 18.19 mutual part are the drain grooves 20, which collects water drops attached to the surface side of the 150 surface. Drain basket 2 to collect water droplets attached to
1 are provided respectively. As shown in FIG. The water that gathers in ゜21 is empty space 1
For reasons such as allowing the water to flow into the drain grooves 3, the side of the cavity 13 is lowered, and each drain groove 20, 21 is given an inclination angle θ. Further, the inclination angle of the slope portions 18 and 19 is set in consideration of the pressure loss when the exhaust gas collides, and in this embodiment, it is about 4'j'.

Regarding the stuck rain prevention device 11 described above, an experimental device as shown in FIG. 3 was manufactured and an experiment was conducted.

First, to explain the experimental apparatus shown in Fig. 5, the chimney 10
A ventilation duct 23 is connected to the lower part of the ventilation duct 2.
A damper 24 and a proar 25 are provided at the end of the pump 3, and the damper 24 and the proar 25 create a state similar to the actual flow of exhaust gas. In addition, a spray nozzle 26 and a pump 27 that sends water to the spray nozzle 26 are provided at an intermediate height position of the chimney 10, and these spray nozzles 26 and pump 27 cause temperature and pressure phenomena (inner periphery of the chimney 10). A phenomenon in which a part of the water film formed on a surface peels off and becomes water droplets and scatters.) Water droplets that should have been formed are now formed.

In addition, the dimensions of each part in the above experimental apparatus are as follows (units are millimeters): Hl (equipment height>=/
lbz, H2 (chimney height) = lI3J0, H3 = u00
．． H4=Y00. p, 1 (chimney diameter) = 71o, D2-4
10. D3=//1oXD4=i4tt.

In addition, in the Lfc water droplet collecting plate shown in Fig. μ, the collecting plate 1
5.15 Dimension of gap 28 between each other C=j 01 Needle face part 1
8.19 length Ll=/4/, width W1 of drain groove 20=
/ 6.

In the above experimental apparatus, the diameter of the nozzle 26 is approximately 0.
An experiment was conducted by generating water droplets on a paper.

The diameter of water droplets formed in an actual chimney is as follows.
However, since the water droplets formed by the nozzle 26 have a lateral pressure within this range and a small particle size, if good results are obtained in this experiment, it will be possible to install it in an actual chimney.
It is estimated that good results can be obtained even in cases where

Regarding the results of the experiment, water droplets ejected from the nozzle 26 and rising inside the chimney 10 by the wind sent from the blower 25 were well captured by each collection plate 15.
It was discharged to the outside of the chimney 10 through the drain pipe 16, and no stuck rain occurred.

In other words, regarding this result, in the experimental device, the height dimension H1 of the stack rain prevention device 11 is
The stuck rain can be prevented with a diameter of about 25 times the diameter D1, which is smaller than the conventional device.

In addition, when considering the action of the stuck rain prevention device 11 to capture water droplets, the following is a general idea.

Water droplets formed at the bottom of the chimney 10 due to the temperature-pressure phenomenon (nozzle 26 in the experiment) rise inside the chimney 10 together with the exhaust gas, as in the conventional case, but the exhaust gas is placed on the adjacent water droplet collection plate 15.15. When the exhaust gas passes through the gap 28 (see FIG. 3 and FIG. μ) between the collecting plates 15,
．． The water droplets that have risen together with the exhaust gas due to this collision will adhere to the slope parts 18, 19, etc., due to the impact. These slope parts 1
8.19 The water droplets that have settled on the water droplet adhere to the inner circumferential surface of the substantially vertical chimney 10 because the flow velocity passing through the gap 28 between the water droplet collection plates 15 and 15 is smaller than the flow velocity inside the chimney lo. The sloped portion 18.
19, is collected in the drain groove 20.21, flows to the air F9r13 as shown by the broken line in FIG. 1, and is discharged to the outside of the chimney 1° by the drain pipe 16.

On the other hand, the exhaust gas from which water droplets have been removed by the collection plate 15 is
Most of the exhaust gas rises inside the cylinder 12 and is accelerated at the nozzle-shaped upper end 12e and is discharged, but some exhaust gas is discharged from the opening 12b of the cylinder 12 when passing through the gap 28. It flows into the space 13, rises through the cavity 13, is accelerated at the upper end 14& of the outer cylinder 14, and is discharged. The exhaust gas rising inside this cavity 13 warms the peripheral wall of the cylinder 12,
This is effective in preventing moisture in the exhaust gas from condensing on the inner circumferential surface of the cylindrical body 12.

In addition, as in the above-mentioned experiment, the reason why the size of the device was less than half that of the conventional one is that the collection plate 15, which serves as a means for capturing water droplets, runs vertically inside the cylinder 12, which serves as a passage for exhaust gas. Since they are arranged in a divided manner, they do not provide much resistance to the rise of exhaust gas, and even if the number of collecting plates 15 is increased to densely divide the inside of the passage, the pressure loss will not become so large.
Each collection plate 15 has slope portions 18 and 19 formed in multiple stages in the flow direction of the exhaust gas to which water droplets adhere. 19
It is thought that water droplets can be captured efficiently in a short ascending distance.

In addition, in order to investigate the effect on soot dust contained in the exhaust gas and peeling pieces of the lining material attached to the inner peripheral surface of the chimney 10, sand was mixed in from the bottom of the chimney 10 using the apparatus shown in FIG. However, it was discovered that sand can also be collected well. The collected t″Lfc sand was discharged together with water from the collection plate 15 to the cavity 13 and from the cavity 13 to the drain pipe 16. As a result, even if powder was mixed in the exhaust gas, It was found that the water droplet trapping effect did not decrease, and that the powder itself could also be trapped.

Although one embodiment has been described above, the structure of the collection plate 15 itself and the mutual arrangement of the collection plates 15 are not limited to the above-described embodiment. For example, as shown in FIGS. 6 and 7, the connecting plate 17 may not be used, and both ends of the collection plate 15 may be directly supported by the cylindrical body 12. Further, as shown in FIG. 1, collection plates 15 may be provided radially around the cylindrical connecting member 29.

Furthermore, the water droplet collecting plate can be modified as shown in FIG.

This water droplet collecting plate 3o in FIG.
．． A V-shaped drain #l is formed between the vertical wall 32 and the upper pressure-jointed vertical wall 32 of 19! 133 is formed.

As shown in FIG. 10, the gutter 31 has one cross section of a circumference of
It has an arc shape with about 4' cut out, and is arranged so that the upper part of the slope part 18, 19 projects into the gutter 31 from the opening 31a, and the lower end part 31b of the gutter 31. It is attached to the upper part of the slope part 18, 19 with consideration given to leaving a gap between the slope part 18 and the slope part 18, 19 through which exhaust gas can flow.

The collection plate 30 having such a structure is suitable when the flow rate of exhaust gas is faster than the collection plate 15 shown in FIG. μ. The reason for this is that as the flow velocity of exhaust gas is gradually increased, a temperature-pressure phenomenon also occurs on the slope portion 18, etc., but even if separation occurs on the slope portion 18 in this way, the In this case, the water droplets separated from the slope part 18 rise along the slope part 18 together with the exhaust gas and flow into the gutter 31, and collide with the inner circumferential surface of the gutter 31 and are captured. The captured water droplets then flow through the inner bottom 31C of the gutter 31 (see FIG. 70) and flow into the cavity 13.
Capture leakage is unlikely to occur even when the flow rate of exhaust gas is high.

When an experiment was conducted using the collection plate 30 shown in Fig. 2 with an experimental apparatus similar to the one shown in Fig. 1, the one shown in Fig. 2 showed good results until the flow velocity reached 7.17 m. We were able to capture water droplets. On the other hand, with the structure shown in Figure 1, the critical flow velocity at which water droplets can be captured is ! f, 73m/
I got it at 8. Therefore, by providing the gutter 31 as shown in Fig. 3, the critical flow velocity was improved by about 3I. If it is possible to improve the critical flow velocity in this way, when processing a certain amount of exhaust gas □, the flow velocity will increase and the chimney diameter can be reduced by 7 times, reducing the chimney diameter. In response to the
It also becomes more compact.

In addition, during the above experiments, the inclination angle θ of the nine trapping plates shown in Fig. 2 was set to θ/00, but as we were busy setting θ to a more appropriate value, the number of water droplets was further increased. It is also possible to improve the capture performance and further downsize. For example, referring to the case where the collection plate 30 shown in Fig. 3 is used and the structure shown in Figs.
=9. t, 2 (m/B) and Natsunaka, e
=, 200t'iVm&x=/0. (7611/
11) was obtained.

As explained above, the stuck rain prevention device of the present invention is provided with a plurality of water droplet collecting plates that partition the inside of the cylinder vertically into a cylinder, which is connected to the top of the chimney and serves as a passage for exhaust gas. The collection plate is used as a means for trapping water droplets that rise together with the exhaust gas, and the collection plate has a plurality of inclined surfaces on which the exhaust gas collides in series along the flow direction of the exhaust gas. Compared to a conventional device that has a zigzag configuration in the flow direction, a porous moisture absorbing material is attached to the inner circumferential surface of the cylinder, and a core moisture absorbent is used as a means to capture water droplets.
The collision efficiency of exhaust gas is high, making it possible to prevent stuck rain with less than half the height of conventional models. In other words, the equipment can be downsized to less than half its size without sacrificing its effectiveness in preventing stuck rain, and by reducing the construction scale due to this downsizing, the construction period can be shortened and construction costs can be reduced accordingly. As a result, it was possible to reduce the In addition, in order to achieve the above-mentioned compactness, it is also recommended to use construction methods such as assembling parts or the whole of the device in a factory and installing the assembled device on an existing chimney. By adopting this construction method, it is possible to improve the workability of construction work and further shorten the construction period.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of a conventional stuck rain prevention device, Figure 2
The figure is a side sectional view of one embodiment of the present invention, and Figure 3 is! Figure 5 is a cross-sectional view taken along the line III--III in Figure 1, Figure 5 is a perspective view of the main parts in Figure 1, Figure 5 is a schematic configuration diagram of the 9 experimental apparatus to which one embodiment is applied, and Figure 6 is a schematic diagram of the experimental apparatus. 7 is a sectional view taken along the line ■-■ in FIG. 6; FIG. R is a sectional view of still another embodiment of the present invention; FIG. A perspective view showing another embodiment of the collection plate applied to the invention, and FIG. 10 is a side view of the main part in FIG. 2. 10... Chimney, 11... Stuck rain prevention device, 12... Cylindrical body, 12a...
・Large diameter part, 12b...Opening part, 12C...
...Top end, 13... Blank space, 14...
External cylindrical body, 14a... Upper end portion, 14b...
... Bottom plate part, 15 ... Water droplet collection plate, 16 ...
... Drain pipe, 17... Connection plate, 18.19.
... Slope section, 20.21 ... Drain groove,
28... Gap, 29... Connecting member, 3
0... Water droplet collection plate, 31... Gutter, 31
'a...Opening part, 31b...Lower end part,
31C...Inner bottom, 32...Vertical wall,
33...Drain groove. 1 Figure 3 Figure 6 Figure 7 Figure 5 Figure 8

Claims (1)

[Claims] A cylindrical body connected to the upper end of the chimney and serving as a passage for exhaust gas, an outer cylindrical body concentrically covering the outer periphery of the cylindrical body to form a space opening upwardly between the cylindrical body and the inside of the cylindrical body. a plurality of water droplet collecting plates partitioned vertically and having at least one side protruding into the space from an opening formed in the peripheral wall of the cylindrical body; A stack rain prevention device characterized in that a plurality of slope parts are arranged in a zigzag shape along the flow direction of exhaust gas, and one side facing the void is inclined downward and held in a cylinder.