KR20110116001A - Ground flare - Google Patents

Abstract

A low frequency vibration generated from a grand flare tower body such as a chimney is properly adjusted to suppress the vibration generation limit of a window or the like, thereby providing a grand flare that prevents surrounding objects from resonating and vibrating. In the grand flare 10 in which the flammable exhaust gas is combusted by the burner 11 at the lower end of the chimney, and the lower end of the chimney 20 and the periphery of the burner 11 are surrounded by the windshield 40, the chimney 20. And at least one of changing the natural frequency generated from the grand flare tower body consisting of the windshield 40, pluralizing the grand flare tower body, and installing a low frequency vibration absorber for the inside of the grand flare tower body, thereby selecting the low frequency of the grand flare tower body. Noise sound pressure level was reduced.

Description

Grand Flare {GROUND FLARE}

The present invention relates to a grand flare used for the combustion treatment of flammable exhaust gas.

Conventionally, the processing apparatus which carries out the combustion process of combustible gas is divided roughly into three types, an incinerator, an open flare stack, and a grand flare stack (grand flare).

As combustible gas combusted by such a processing apparatus, for example, in an integrated coal gasification combined cycle (IGCC), there is a gas produced by gasifying coal at the initial start-up of a plant. There is an unsuitable flammable exhaust gas. In addition, the coal gasification combined cycle power plant is a facility that gasifies coal as a fuel to drive a gas turbine, and generates power using the driving force of the gas turbine and the arrangement of the gas turbine.

An incinerator (refer FIG. 24) installs the air blower 2 in the incinerator main body 1 formed from refractory etc., and combusts flammable gas. In this case, there exists a problem that the cost of the refractory body shape | molding the incinerator main body 1, and the cost of the air blower 2 are expensive. For reference, reference numeral 3 in the drawings denotes a burner, and reference numeral 4 denotes a chimney.

The open flare stack (refer FIG. 25) is an apparatus which ejects fuel in air | atmosphere, and combusts flammable gas by an ignition apparatus. Normally, the outlet of the fuel is disposed at the high position of the flare stack body 5. Since combustion air is supplied by natural intake air from the surroundings, an air blower is not required and the cost is low. However, since the flame is in an exposed state, problems of fire occurrence due to radiation to the surroundings, noise due to the burning sound of the flame, and landscape inconsistency due to the conspicuous flame are pointed out.

For example, as shown in FIG. 26, the grand flare 6 opens the lower end of the chimney 7 and provides one or a plurality of flammable gas combustion burners 8 at the lower end of the chimney 7. It becomes a structure. In this case, since the chimney 7 and the windshield 9 are required, the cost is higher than that of the open flare stack. However, the grand flare 6 has the advantage that a flame is surrounded by the windshield 9 and is not seen from the outside, and combustion noise is reduced by the chimney.

As a prior art which reduces the noise derived from a chimney, there exists a sound absorption member in the internal position of a chimney (for example, refer patent document 1).

Moreover, in the grand flare stack, the structure by which the noise blocking member surrounding the combustion chamber was provided in sound absorption with respect to the airflow sent to a combustion chamber is disclosed (for example, refer patent document 2).

Moreover, the noise reduction apparatus which noises by the noise which generate | occur | produces within the flue | emission of forced exhaust gas of combustion gas by a noise disappears is disclosed (for example, refer patent document 3).

Japanese Patent Publication No. 58-2331 Japanese Patent Laid-Open No. 54-45838 Japanese Patent No. 2629410

By the way, in the conventional grand flare 6 mentioned above, it becomes a problem that the surrounding object resonates and vibrates by the low frequency vibration which generate | occur | produces from the chimney 7.

As a conventional low frequency vibration countermeasure in the grand flare 6, the reduction of the amount of air, the change of the burner flow rate, and the change of the number of burners are known for the purpose of flame-extinguishing. However, such conventional low frequency vibration countermeasures have a problem that the flame is spouted from the top of the stack due to the increase in unburned content due to the deterioration of combustibility or the enteritis.

Moreover, in the countermeasure which arrange | positions each level nonuniformly about the some burner 3, and makes the flame surface which is a vibration source uneven, and reduces the sound pressure generated, the burner 8 arrange | positioned at the upper side has a burner flame of a lower side. There is a problem of contact and damage.

In addition, there is a method of limiting the chemical calorific value of the gas treated in the grand flare 6, or a method of operating only during the day when the noise standard is loose, but all are not economical because they are limited to the operation of the plant.

Against this background, by preventing resonance of the low frequency frequency of the grand flare tower body and the natural frequency of burner combustion, and / or converting the vibration energy into thermal energy, the sound pressure level of low frequency noise is suppressed from increasing and the low frequency generated from the grand flare It is preferable to reduce the vibration to suppress the vibration generation limit below the window.

This invention is made | formed in view of the said situation, The objective is to adjust the low frequency vibration which generate | occur | produces from the grand flare tower bodies, such as a chimney, to suppress below the vibration generation limit of a window and the surrounding object to resonate and vibrate It is to provide the grand flare which prevented it.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, this invention employ | adopted the following means.

A grand flare according to an aspect of the present invention is a grand flare in which a combustible exhaust gas is burned by a burner at a lower end of a chimney, and a surrounding of the chimney lower end and the burner is surrounded by a windshield. The low frequency noise sound pressure level of the grand flare tower is reduced by selecting at least one of a change in natural frequency generated from the grand flare tower, pluralization of the grand flare tower, and installation of a low frequency vibration absorber inside the grand flare tower. It is.

According to such a grand flare, the grand flare is selected by selecting at least one of a change in natural frequency generated from the grand flare tower body consisting of a chimney and a windshield, pluralization of the grand flare tower body, and a low frequency vibration absorber installation inside the grand flare tower body. By reducing the low frequency noise sound pressure level of the tower body, it is possible to set the low frequency vibration generated from the grand flare below the window vibration generation limit.

In the above aspect, it is preferable that the change of the natural frequency generated from the grand flare tower body forms a windshield opening in a part of the windshield, and closes the windshield opening with a non-walled sheet material for low frequency sound. As a result, the sound pressure level can be lowered by changing the generated frequency in a direction of increasing.

In this case, it is preferable that the said windscreen opening part makes a circumferential opening ratio 50% or more, and makes a height opening rate 70% or more.

In addition, what is necessary is just to select the sheet material surface density of the said non-walled sheet material according to the outstanding frequency before a windscreen opening.

In the above aspect, the change of the natural frequency generated from the grand flare tower is preferably formed by forming a chimney opening in a part of the chimney. Thus, the sound pressure level is changed by changing the generated frequency in a direction of increasing the frequency. You can get off.

In this case, it is preferable that the said chimney opening is a horizontal opening formed in the range of 90 degrees-360 degrees in a circumferential direction. That is, the chimney opening of the present invention may be opened as large as the structural strength allows within the range of 90 ° to 360 ° in the circumferential direction.

Moreover, it is preferable that the height direction position of the said horizontal opening is arrange | positioned in the part which doubles the sound pressure mode generate | occur | produced by a resonance frequency.

Moreover, about the said horizontal opening, it is preferable to make opening area ratio into 25% or more irrespective of opening shape.

Moreover, the said horizontal opening may be formed in multiple numbers in the chimney height direction.

In the above aspect, the chimney opening may be one or a plurality of vertical openings that are opened in the chimney height direction.

In the above aspect, it is preferable to form a gap on the outside of the chimney opening to provide an opening covering member, and to set the gap area formed between the gap and the chimney to be larger than the opening area of the chimney opening. For this reason, the sound pressure level can be lowered by changing the generated frequency in the direction of increasing the frequency, and in addition, the flame in the chimney can be prevented from being seen from the outside through the chimney opening by the opening blocking member.

In the above aspect, the change of the natural frequency generated from the grand flare tower body is such that the burner position ζ 'of the burner obtained by Equation 1 is adjusted to the entire length of the passage including the chimney and the windshield. It is preferable that the windshield is installed in the range of 2.2 to 3.4 from the windshield inlet, whereby the sound pressure level can be lowered by changing in the direction of lowering the generated frequency.

In this case, the length of the chimney and / or the windshield may be increased to extend the entire length of the passage.

In the above aspect, it is preferable that the pluralization of the grand flare tower is made by combining different excellent frequencies, and as a result, the sound pressure level at each excellent frequency is lowered and dispersed, thereby reducing the overall noise level. You can get off.

In the above aspect, the low-frequency vibration absorber installation in the inside of the grand flare tower body is formed by lining a plurality of sheet members with an inclination angle from the vertical direction in a noise passage formed between the windshield and the chimney. Preferably, the sheet member absorbs vibrational energy of air particles due to noise, and therefore noise can be reduced.

It is preferable that the inclination angle in this case is set in the range of 10 degrees-60 degrees.

Moreover, it is preferable that the said sheet | seat material is bent in multiple numbers.

In addition, it is preferable to install a top plate at the upper portion of the inlet of the noise passage.

According to the present invention described above, the low frequency vibration generated from the grand flare can be set below the vibration generation limit of the window and the surrounding objects can be prevented from resonating and vibrating.

1: is sectional drawing which shows a structural example as one Embodiment of the grand flare which concerns on this invention.
2 is a diagram showing sound pressure levels of low frequency vibration generated from the grand flare tower body.
3 is a perspective view showing a configuration example of a windshield opening as a first embodiment of the grand flare according to the present invention (high-frequency side movement of the natural frequency).
4A is a diagram showing the relationship between the aperture ratio of the windshield opening and the peak sound pressure level, and is a diagram showing the relationship between the peripheral aperture ratio and the peak sound pressure level.
4B is a diagram showing the relationship between the aperture ratio of the windshield opening and the peak sound pressure level, and is a diagram showing the relationship between the height aperture ratio and the peak sound pressure level.
FIG. 5 is a diagram showing a relationship between an excellent frequency before opening of a windshield and a sheet material surface density with respect to a design suitable range of a non-walled sheet material. FIG.
FIG. 6: is a perspective view which shows the structural example of the chimney opening used as the horizontal opening as a modification of 1st Embodiment. FIG.
FIG. 7: A is a figure which shows the definition of the opening area ratio with respect to the chimney opening of a horizontal opening, and is a figure which shows the curved square area opening area S. FIG.
FIG. 7: B is a figure which shows the definition of the opening area ratio with respect to the chimney opening of a horizontal opening, and is a figure which shows the opening area ratio S 'of a circular hole.
8: A is a perspective view which shows the structural example of the chimney opening which made multiple stages of a horizontal opening.
8B is a longitudinal cross-sectional view illustrating a configuration example of a chimney opening having multiple stages of horizontal openings.
9 is a perspective view illustrating a configuration example of a chimney opening serving as a vertical opening.
It is a perspective view which shows the structural example which provided the opening cover member in the chimney opening used as the vertical opening.
FIG. 10B is a cross sectional view showing a configuration example in which an opening shielding member is provided in a chimney opening serving as a vertical opening. FIG.
11: A is a perspective view which shows the structural example which provided the opening cover member in the chimney opening used as the horizontal opening.
It is a longitudinal cross-sectional view which shows the structural example which provided the opening cover member in the chimney opening used as the horizontal opening.
FIG. 12A is a cross-sectional view showing a configuration example in which the windshield is overlapped and the windshield length is extended as a second embodiment of the grand flare according to the present invention (low-side movement of the intrinsic frequency).
FIG. 12B is a longitudinal cross-sectional view showing a configuration example in which the windshield is overlapped and the windshield length is extended as the second embodiment (the low-side movement of the natural frequency) of the grand flare according to the present invention.
FIG. 13A is a cross-sectional view showing a configuration example in which the windscreen is extended in two stages by extending the windscreen as a modification of the second embodiment.
FIG. 13B is a longitudinal sectional view showing a configuration example in which the windscreen is extended in two stages by extending the windscreen as a modification of the second embodiment.
FIG. 14A is a cross-sectional view showing a configuration example in which the length of the windshield is extended by combining the overlap of the windshield and extending laterally as a modification of the second embodiment.
FIG. 14B is a longitudinal sectional view showing a configuration example in which the length of the windshield is extended by combining an extension of the windshield to the side as a modification of the second embodiment.
FIG. 15 is a diagram showing a design suitable range in the relationship between the burner position ζ 'and the peak sound pressure level.
FIG. 16: is a perspective view which shows the structural example which carried out two towers as 3rd embodiment (multiple towers) of the grand flare which concerns on this invention.
FIG. 17 is a perspective view illustrating a configuration example in which three chimneys are formed as a modification of the third embodiment. FIG.
FIG. 18A is a perspective view illustrating a configuration example in which the chimney interior is divided into three towers as a modification of the third embodiment. FIG.
18B is a cross sectional view showing a configuration example in which the chimney inside is divided into three towers as a modification of the third embodiment.
19 is a cross sectional view showing a configuration example in which the chimney inside having a hexagonal cross section is divided into three towers.
It is explanatory drawing about superposition of the outstanding frequency in multiple towers of a grand flare.
It is a perspective view which shows 4th embodiment (sound absorption system method) of the grand flare which concerns on this invention.
FIG. 22: is a front view which shows the example of arrangement | positioning of the sheet | seat material (part) shown in FIG.
FIG. 23: is a front view which shows the example of arrangement | positioning in the case where the sheet | seat material (part) shown in FIG. 21 is bent in "" shape.
24 is a diagram showing a configuration example of an incinerator as an example of a conventional apparatus for combusting a combustible gas.
25 is a diagram showing an example of the configuration of an open flare stack as an example of a conventional apparatus for combusting a combustible gas.
26 is a diagram illustrating a conventional example of the grand flare.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of the grand flare which concerns on this invention is described based on drawing.

The grand flare 10 shown in FIG. 1 is an apparatus for burning and combusting flammable gas with the burner 11 provided in the lower end part of the chimney 20, opening the lower end part of the chimney 20. FIG. The lower end of the chimney 20 is surrounded by the windshield 40 around one or more burners 11. By providing such a windshield 40, the burner 11 provided in the lower end of the chimney 20 is not influenced by the surrounding wind, and the flame is not seen from the outside.

In the grand flare 10 configured as described above, in the present invention, the natural frequency change of the low frequency sound (noise) generated from the grand flare tower body consisting of the chimney 20 and the windshield 40, the chimney 20 and the windshield ( The low frequency noise sound pressure level of the grand flare tower body is reduced by selecting at least one of the pluralization of the grand flare tower body consisting of 40) and the installation of the low frequency vibration absorber inside the grand flare tower body consisting of the chimney 20 and the windshield 40. do.

That is, the grand flare 10 of this invention is a countermeasure which changes the natural frequency of the low frequency sound which generate | occur | produces with respect to the grand flare tower body which consists of the chimney 20 and the windshield 40, the countermeasure which multiplexes a grand flare tower body, and The low frequency noise sound pressure level of the grand flare tower body is reduced by selecting at least one of the measures for providing a low frequency vibration absorber inside the grand flare tower body and combining one or more measures.

In FIG. 2, the sound pressure level of the low frequency vibration (noise) which arises from the grand flare tower body is shown by the broken line in the grand flare 10 mentioned above. Here, the horizontal axis in the figure is the excellent frequency (Hz), the vertical axis is the sound pressure level (dB).

According to the figure, the sound pressure level of the low frequency vibration has a convex curve on the upper side and intersects the window vibration occurrence limit indicated by the straight line of the right ascending at two excellent frequencies f1 and f2. Since the window vibration generation limit is the upper limit of the sound pressure level at which the window vibration occurs, it is necessary to set the sound pressure level of the low frequency vibration to a region lower than the window vibration generation limit. In addition, the sound pressure level before the countermeasure demonstrated below becomes a value higher than the window vibration generation limit.

Therefore, with respect to the sound pressure level of the low frequency vibration generated from the grand flare tower of the grand flare 10, a design suitable range exists in both the region where the excellent frequency is smaller than f1 and the region where the excellent frequency is larger than f2. . For this reason, in the low frequency vibration generated from the grand flare tower body, the sound pressure level of the grand flare tower body becomes lower than the window vibration generation limit by lowering the excellent frequency to f1 or raising the excellent frequency to f2. As a result, the sound pressure level of the low frequency vibration generated from the grand flare 10 can be set below the window vibration generation limit, thereby preventing the surrounding objects from resonating and vibrating.

Hereinafter, the structure and countermeasure for making it into the design suitable range below the window vibration generation limit by reducing the low frequency noise (sound pressure level) of the grand flare 10 are demonstrated concretely.

The above-described configuration and countermeasures are roughly classified into the following four types.

1) The natural frequency of low frequency sound generated from the grand flare tower body is moved to the high side to prevent resonance with the natural frequency of burner combustion.

2) The natural frequency of low frequency sound generated from the grand flare tower body is moved to the low side to prevent resonance with the natural frequency of burner combustion.

3) Multiple towers of the grand flare are used to increase the sound pressure reduction effect due to the decrease in the amount of heat to be processed. do.

4) An object (low frequency vibration absorber) that absorbs low frequency vibration is provided inside the tower body of the grand flare.

By implementing such a configuration and countermeasures alone or in combination as appropriate, the resonance frequency of burner combustion and the grand flare host vibration are prevented from resonating and the sound pressure level of the low frequency noise generated from the grand flare tower body is reduced. can do. Further, the low frequency vibration absorber can convert the vibration energy into thermal energy to reduce the sound pressure level of the low frequency noise.

<1st embodiment; Treble side movement of intrinsic frequency>

Embodiment described below moves the natural frequency of the low frequency sound which generate | occur | produces from a grand flare tower body to the high pitch side, and prevents resonance with the natural frequency of burner combustion.

In the grand flare 10A shown in FIG. 3, the windshield opening 41 is formed in a part of the windshield 40, and the windshield opening 41 is blocked by the non-walled sheet material 42 to change the natural frequency. Doing. That is, a part of the windshield 40 is cut off to form the windshield opening 41, and then the non-walled sheet member 42 is attached to the windshield opening 41 to be blocked. The non-walled sheet material 42 used here is a material which does not function as a wall surface with respect to low frequency sound in addition to preventing a windscreen and an audible sound leakage, and preventing a flame from seeing through the windscreen opening part 41.

The windshield opening 41 formed by removing part of the windshield 40 has an opening area having a circumferential aperture ratio of 50% or more and a height aperture ratio of 70% or more in the aperture ratio (see FIG. 3) defined below. It is preferable to remove a board | plate material from the windshield 40, and to remove it. In the illustrated windscreen opening part 41, the curved square opening part is arrange | positioned at equal pitch in the circumferential direction.

Perimeter aperture ratio = n × w / πD × 100

n; Number of windshield openings

w; Circumference of the windshield opening

π; Circumference

D; Diameter of windscreen

Height opening ratio = h / H * 100

h; Height of windshield opening

H; Overall height of the windscreen

4A and 4B are diagrams showing the relationship between the aperture ratio (%) and the peak sound pressure level (dB).

In the case of the peripheral aperture ratio shown in Fig. 4A, as the aperture ratio increases from 0, the peak sound pressure level also rises, and the aperture ratio peaks at about 20%. When the peak passes, the peak sound pressure level also decreases as the aperture ratio increases, and even if the aperture ratio increases by about 50% or more, there is little variation in the peak sound pressure level. Therefore, it is preferable to set it as 50% or more about a circumferential opening ratio.

In the height aperture ratio shown in Fig. 4B, in the region where the aperture ratio is about 0 to 70%, the peak sound pressure level decreases as the aperture ratio increases. In the region where the opening ratio is larger than about 70%, there is almost no change in the peak sound pressure level due to the increase in the opening ratio. Therefore, it is preferable to set it as 70% or more about a height aperture ratio.

In addition, it is preferable that both opening ratios satisfy | fill the conditions with respect to the above-mentioned peripheral opening ratio and height opening ratio of the windscreen opening part 41.

The non-walled sheet member 42 is provided with, for example, a sheet member such as a soundproof sheet in the windshield opening 41 so as not to form a wall surface with respect to low frequency sound. The range of the sheet material surface density which is very suitable as the non-walled sheet material 42 is different depending on the excellent frequency before opening of a windscreen, as shown in FIG. That is, it is necessary to select the heavy non-walled sheet | seat material 42 which is high in sheet material surface density, so that the case where the outstanding frequency before a windscreen opening is small. In other words, the sheet material surface density of the non-walled sheet material 42 is preferably selected in the region below the boundary of the design suitable range shown in FIG. 5.

That is, when the surface density of the non-walled sheet material 42 is made small, the outstanding frequency changes, and since the outstanding frequency changes, the surface density of the non-walled sheet material 42 is made small and the effect of a windscreen opening is acquired. It is necessary to select the material of the plane density according to the initial frequency band.

Here, in order to increase the outstanding frequency is a frequency 5Hz a windshield sheeted, approximately 3000g / m ² select a light material than, and, to the frequency 25Hz increasing the excellent frequency by a windshield sheeted, greater than about 300g / m ² In order to select a light material and increase the frequency of 80 Hz by the windshield sheet, it is necessary to select a material that is lighter than approximately 30 g / m ² .

With this configuration, since the frequency of the vibration generated from the grand flare 10A is increased, it becomes possible to avoid the resonance point with the natural frequency of the burner 11.

In addition, since the attenuation in the chimney 20 increases in the vibration of high frequency, a noise level falls. That is, in order to solve the problem of the noise reduction which the conventional grand flare 10 has, the high frequency side movement of natural frequency demonstrated here forms the windshield opening part 41 in the windshield 40, and the non-walled sheet material The structure prevented by (42) reduced the sound pressure level of low frequency noise while raising the generation frequency.

Next, the modification which formed the chimney opening part of the chimney 20 instead of the windscreen opening part 41 of the windscreen 40 in 1st Embodiment mentioned above is demonstrated. In the above modification, in order to change the natural frequency generated from the grand flare tower, that is, to move the natural frequency of the low frequency sound generated from the grand flare tower to the high side, a chimney opening ( 21) to prevent resonance with the natural frequency of burner combustion.

The grand flare 10B shown in FIG. 6 is equipped with the chimney opening 21 of the horizontal opening formed in the place of the chimney 20 which becomes upper than the position enclosed by the windscreen 40. The chimney opening 21 is formed in a range of 90 ° to 360 ° in the circumferential direction of the chimney 20, and it is preferable that the chimney opening 21 is a large opening as long as the structural strength allows.

In addition, in order to reduce the sound pressure level in the chimney 20 efficiently, the chimney opening 21 shown in FIG. 6 is set to the part which the position of the height direction of a horizontal opening becomes double of the sound pressure mode generate | occur | produced by a resonance frequency. have.

As the chimney opening 21 of the horizontal opening mentioned above, a round hole, a square hole, etc. can be employ | adopted as an opening shape at the time of opening, for example, as shown to FIG. 7A and 7B, and an opening shape is specifically limited It is not. However, the opening area ratio of the chimney opening 21 is preferably 25% or more regardless of the opening shape of the horizontal opening. That is, for example, as shown in FIG. 7A, the opening area ratio S when the chimney opening 21 is curved, or, for example, as shown in FIG. 7B, the chimney opening 21 ′. The aperture area ratio S 'in the case where) is composed of a plurality of circular holes is 25% or more.

In addition, in the formula which defines the opening area ratio S in FIG. 7A, n is the number of the chimney opening 21, w is the circumferential length of the chimney opening 21, h is the height of the chimney opening 21, and FIG. In the formula for defining the opening area ratio S 'at 7b, n is the number of the chimney openings 21', π is the circumferential rate, d is the diameter of the chimney opening 21 ', and D' is the diameter of the chimney 20. h is the height of the chimney opening 21 '.

By the way, although the chimney opening part 21 and 21 'of the horizontal opening mentioned above is formed in only one stage in the height direction of the chimney 20, for example, as shown to FIG. 8A and FIG. 8B, It may be formed by arranging a plurality of stages in the height direction.

In the structural example of the chimney 20A shown in FIGS. 8A and 8B, the conical trapezoidal ring members 23 are arranged at the same pitch in the height direction with respect to the plurality of pillar members 22, and the upper and lower ring members are fixed. A plurality of gaps formed between the 23 and 23 functions as the multistage chimney opening 21A. In this case, by considering the vertical arrangement of the ring member 23, when the chimney 20A is viewed in the horizontal direction, it is also possible to set the chimney opening 21A in which the opening is not seen, that is, the flame is hardly seen from the outside. Do.

In addition, unlike the horizontal opening mentioned above, the chimney 20B shown in FIG. 9 is equipped with the chimney opening 21B of the vertical opening opened in the chimney height direction. In the illustrated configuration example, two chimney openings 21B having vertical openings are formed using a pair of chimney members 24 and 24 having a substantially C-shaped cross section.

Moreover, in the case of the chimney 20C shown to FIG. 10A and FIG. 10B, one chimney opening 21C used as the longitudinal opening is provided. In the chimney opening 21C, in order to prevent the flame from being seen from the outside, an opening blocking member 25 is provided at a predetermined interval outside the chimney 20C. The spacing area formed between the chimney 20C and the opening covering member 25 is set larger than the opening area of the chimney opening 21C so that the effect of reducing low frequency noise is not lost. In addition, such an opening cover member 25 can be provided in the chimney opening 21 of a horizontal opening, etc., For example, as shown to FIG. 11A and 11B, it covers the outer periphery of the chimney opening 21 of a horizontal opening. The opening cover member 25 'can be provided. In this case, the space area Sa * 2 formed between the chimney 20 and the opening cover member 25 'is set larger than the opening area Sb of the chimney opening 20 (2Sa> Sb). .

Thus, even if it is set as the structure which forms the chimney opening 21 in the chimney 20 side, since the frequency of the vibration which arises from the grand flare 10B 'like the windscreen opening 41 becomes high, the burner 11 The resonance point with the natural frequency can be avoided.

In addition, since the attenuation in the chimney 20 increases in the vibration of high frequency, a noise level falls. That is, the high-frequency side movement of the natural frequency described herein is generated as a structure in which the chimney opening 21 is formed in a part of the chimney 20 in order to solve the problem of noise reduction of the conventional grand flare 10. The higher the frequency, the lower the sound pressure level of low frequency noise.

<2nd embodiment; Low-side movement of intrinsic frequency>

Embodiment described below moves the natural frequency of the low frequency sound which generate | occur | produces from a grand flare tower body to the low side, and prevents resonance with the natural frequency of burner combustion. That is, as shown in FIGS. 12A to 15, the sound pressure level of low frequency noise is lowered while extending the windshield to lower the generated frequency.

In the said system, the burner position (ζ ') of the burner 11 calculated | required using FIG. 15 and [Equation 1] shown below contains the chimney 20 and the windshield 40A (path | path total length). On the other hand, it is provided so as to be in the range of 2.2 to 3.4 from the inlet Wi of the windshield 40A.

L1: Chimney height (m)

d ₁ : chimney diameter (m)

c: sound velocity (m / s)

f: measurement frequency (Hz)

Here, in [Equation 1], L1 is the chimney height m, d ₁ is the chimney diameter m, c is the speed of sound (m / s), and f is the measurement frequency (Hz).

The relationship between the burner position ζ 'calculated by Equation 1 and the peak sound pressure level decreases past the peak as shown in FIG. 15. Therefore, the design suitable range of the burner position ζ 'becomes an area ζ' = 2.2 to 3.4 which becomes a value lower than the peak sound pressure level (peak sound pressure level at ζ '= 0) of the inlet Wi.

In order to set the burner position ζ 'within the above-described design suitable range, for example, the first overlapping portion 43 is formed on the windshield 40 such as the grand flare 10D shown in FIGS. 12A and 12B. One windscreen 40A extends the windscreen length. In the windshield 40A having such an overlapping stage 43, the opening of the inlet Wi of the windshield 40A is disposed downward.

In addition, like the windshield 40B of the grand flare 10E shown to FIG. 13A and FIG. 13B, you may extend a windscreen length by two overlapping parts 43 and 44 (or two or more stages), For example, like the windshield 40C of the grand flare 10F shown in FIG. 14A and FIG. 14B, you may combine the overlap part 43 and the extension part 45 to the side.

With such a configuration, the frequency of vibration generated from the grand flares 10D to 10F is lowered by the extension of the windbreak length and / or the extension of the chimney length. By lowering the frequency in this way, it is possible to avoid the resonance point of the problem caused by the vibration. In addition, as the volumes of the grand flares 10D to 10F increase, the internal attenuation increases, so the noise level decreases.

<3rd embodiment; multiple tower shoes>

The embodiment described below is to reduce the sound pressure level by combining a plurality of grand flare towers and combining different excellent frequencies.

In the present embodiment, for example, as shown in FIG. 16, two grand flares 10a and 10b divided into two parts are provided so as to have a necessary capability. In this case, the grand flare 10a, 10b divided into two changes the chimney length of the chimney 20a, 20b, and each outstanding frequency is set differently, and the grand flare 10b with a long host length is long. The excellent frequency becomes low tone, and the excellent frequency of grand flare 10a whose host length is short becomes high tone. In other words, the two grand flares 10a and 10b are arranged with different primary frequencies. In addition, in the said division example, both a chimney and a windscreen are divided into two. For reference, reference numerals 40a and 40b in the drawings represent windshields.

In this way, when two grand flares 10a and 10b having different excellent frequencies are provided side by side, the sound pressures do not overlap each other due to the difference in the primary frequency as shown in the lower part of FIG. Therefore, since each sound pressure level is reduced (about 3 dB) by two divisions, the sound pressure level to the whole grand flare 10a, 10b is suppressed below the window vibration generation limit shown by a dashed-dotted line in FIG.

However, when two grand flares with the same excellent frequency are provided side by side, since the primary frequencies are the same, as shown in the upper part of FIG. 20, the sound pressures of each other overlap and the reduction is canceled. Therefore, it becomes difficult to suppress the sound pressure level to the whole grand flare 10a, 10b below the window vibration generation limit shown by a dashed-dotted line in a figure.

By the way, the multiple tower | segmentation of the grand flare mentioned above is not limited to the above-mentioned two division | segmentation, You may divide into three or more divisions, and may multiply. In this case, if each tower frequency is set to have a different value and is multi-topped, there is no need to equally distribute the amount of gas to be treated. Therefore, since it can adjust suitably according to the output sound pressure level, it is possible to lower a sound pressure level in a desired frequency band.

In the division example shown in FIG. 17, only the chimney is divided into three into 20a, 20b, and 20c by making a windbreak common. Also in this case, the length of each chimney is set different, and each excellent frequency is set to be different.

In the division example shown to FIG. 18A and 18B, the inside of the chimney 20D which has a circular cross section is divided into partition members 26, and is divided into three, for example, the height position of the chimney opening 21 is changed, Each excellent frequency is set differently. In addition, the cross-sectional shape of the chimney 20D is not limited to a circular cross section, and for example, as shown in FIG. 19, the inside of the chimney 20E having a hexagonal cross section is divided into three parts by the partition member 26. You may share.

<4th embodiment; Sound absorption material system>

In the embodiment described below, a low-frequency vibration absorber is provided inside the grand flare column to absorb vibration energy of air particles caused by noise to reduce noise.

In the embodiment shown in FIG. 21 and FIG. 22, the inclination angle from the vertical direction is provided in the noise passage 50 formed between the windshield 40 and the chimney 20 as a low frequency vibration absorber provided inside the grand flare tower body. Many sheet | seat material 60 is lined up in the shape of a foot. The sheet member 60 in this case becomes plate-shaped, and the inclination angle which hangs the said sheet member 60 is set in the range of 10 degrees-60 degrees with respect to a perpendicular direction.

That is, by installing the sheet material 60 inclined, the low-frequency noise in the noise passage 50 is prevented from going straight through the gap formed between the sheet materials 60 and 60. As a result, the low frequency noise is reflected on the surface of the sheet material 60, so that the noise reduction effect can be enhanced, and the decrease in the amount of intake air due to the sheet material 60 being sag can be prevented. Therefore, since the sheet material 60 absorbs the vibration energy of the air particle by the low vibration noise efficiently, the low vibration noise can be reduced.

In addition, although the sheet | seat material 60 was made into plate shape in embodiment mentioned above, as shown, for example in FIG. 23, you may employ | adopt the sheet | seat material 61 bent once or several times in the "ku" shape. . Since the sheet member 61 makes it more difficult to straighten the low frequency noise in the noise passage 50, the contact area with the air particles can be increased to improve the noise reduction effect.

Moreover, it is preferable to provide the top plate 70 in the upper part of the inlet of the said noise passage 50 mentioned above. The top plate 70 is provided at predetermined intervals from the inlet (upper passage) of the noise passage 50, and is provided to cover the entrance of the noise passage 50 in plan view.

When such a top plate 50 is provided, since the straightness of low frequency noise is inhibited, the noise reduction effect can be further improved.

Thus, although the above-mentioned 1st Embodiment-4th embodiment have sufficient low frequency noise reduction effect each independently, it implements combining each embodiment suitably according to various conditions, such as a flare stack and its installation place. Also good.

In the embodiment of the combination shown in FIG. 1, the sheet member 60 provided in the chimney opening 21 formed in the chimney 20, the windshield opening 41 formed in the windshield 40, and the noise passage 50. And the top plate 70 provided at the upper part of the inlet of the noise passage 50 are used simultaneously, but the present invention is not limited thereto. In addition, the non-walled sheet | seat material 42 is attached to the windscreen opening part 42, and the opening cover member 25 'is attached to the outer periphery of the chimney opening part 21. As shown in FIG.

As described above, the grand flare of the present invention includes at least one of a change in natural frequency generated from the grand flare tower body consisting of a chimney and a windshield, pluralization of the grand flare tower body, and a low frequency vibration absorber installation inside the grand flare tower body. Since the low frequency noise sound pressure level of the grand flare tower body is reduced, the low frequency vibration generated from the grand flare can be set below the vibration generation limit of the window and the surrounding objects can be prevented from resonating and vibrating.

In addition, this invention is not limited to embodiment mentioned above, It can change suitably within the range which does not deviate from the summary of this invention.

10, 10A ~ 10F: Grand Flare 11: Burner
20, 20A ~ 20E: Chimney 21, 21A ~ 21C: Chimney opening
25, 25 ': Blind opening member 40, 40A ~ 40C: Windshield
41: windshield opening 42: non-walled sheet material
50: noise passage 60, 61: sheet material
70: top plate

Claims (18)

In a flare in which flammable exhaust gas is combusted in a burner at the lower end of the chimney, and the surroundings of the chimney lower end and the burner are surrounded by a windshield,
The grand flare tower body is selected by selecting at least one of a change in natural frequency generated from the grand flare tower body consisting of the chimney and the windshield, pluralization of the grand flare tower body, and a low frequency vibration absorber installation in the inside of the grand flare tower body. Low frequency noise sound pressure level characterized in that
Grand flare. The method of claim 1,
The change in the natural frequency generated from the grand flare tower body is characterized by forming a windshield opening in a part of the windshield and blocking the windshield opening with a non-walled sheet material for low frequency sound.
Grand flare. The method of claim 2,
The windshield opening has a circumferential opening ratio of 50% or more and a height opening ratio of 70% or more.
Grand flare. The method according to claim 2 or 3,
The sheet material surface density of the non-walled sheet material is selected according to the excellent frequency before the windscreen opening.
Grand flare. The method of claim 1,
The change of the natural frequency generated from the grand flare tower body is formed by forming a chimney opening in a part of the chimney.
Grand flare. The method of claim 5, wherein
The chimney opening is a horizontal opening formed in a range of 90 ° to 360 ° in the circumferential direction.
Grand flare. The method according to claim 6,
The height direction position of the said horizontal opening is arrange | positioned in the part which doubles the sound pressure mode generate | occur | produced by a resonance frequency, It is characterized by the above-mentioned.
Grand flare. The method according to claim 6 or 7,
The opening area ratio of the said horizontal opening was made into 25% or more, It is characterized by the above-mentioned.
Grand flare. The method according to claim 6,
A plurality of said horizontal opening is formed in the chimney height direction, It is characterized by the above-mentioned.
Grand flare. The method of claim 5, wherein
The chimney opening is one or a plurality of vertical openings which are opened in the chimney height direction.
Grand flare. 11. The method according to any one of claims 5 to 10,
A gap is formed outside the chimney opening to provide an opening covering member, and an interval area formed between the gap and the chimney is set larger than the opening area of the chimney opening.
Grand flare. The method of claim 1,
The change of the natural frequency generated from the grand flare tower body is performed by setting the burner position ζ 'of the burner obtained by Equation 1 from the windshield inlet with respect to the entire length of the passage including the chimney and the windshield. Characterized in that the installation in the range of 3.4
Grand flare. The method of claim 12,
Characterized in that the length of the chimney and / or the windshield is increased, so that the entire length of the passage is extended.
Grand flare. The method of claim 1,
The pluralization of the grand flare tower body is achieved by combining different frequencies.
Grand flare. The method of claim 1,
The low frequency vibration absorber installed in the inside of the grand flare top body is formed by lining a plurality of sheet materials with an inclination angle from the vertical direction in a noise passage formed between the windshield and the chimney.
Grand flare. The method of claim 15,
The inclination angle is set in the range of 10 ° ~ 60 °
Grand flare. The method of claim 15,
The sheet member is bent in plurality.
Grand flare. The method according to any one of claims 15 to 17,
Characterized in that the top plate is installed in the upper portion of the inlet of the noise passage
Grand flare.

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