KR102274772B1 - Micro-Particles in Exhaust Gas Conglomerating Apparatus Having a Vibro-Acoustic System - Google Patents

Abstract

A device for agglomerating fine particles in exhaust gas including an acoustic vibration system according to the present invention includes an acoustic vibration system for agglomerating and collecting fine particles contained in the exhaust gas flowing through an exhaust path in an exhaust duct. The acoustic vibration system includes an acoustic radiation module that is provided on one side area of the periphery of the exhaust duct and radiates an audible sound of a preset wavelength in the form of a plane wave to form a nodal plane having a predetermined standing wave ratio in the exhaust path to distribute fine particles contained in the exhaust gas cohesively.

Description

Exhaust Gas Fine Particle Coagulation Treatment Apparatus Including Acoustic Vibration System {Micro-Particles in Exhaust Gas Conglomerating Apparatus Having a Vibro-Acoustic System}

The present invention relates to an exhaust gas fine particle agglomeration processing device, and more particularly, to an exhaust gas fine particle agglomeration processing device capable of aggregating and treating fine particles contained in exhaust gas discharged to an exhaust duct through an acoustic vibration system. is about

Microparticles in the atmosphere are a global problem that has a decisive adverse effect on human respiration, and has recently emerged as a major social issue.

Such fine dust is classified into PM10 (fine dust), a particulate matter with a diameter of 10 m or less, and PM2.5 (ultra-fine dust), a particulate matter less than 2.5 m in diameter, and is harmful to the human body due to its small particle size.

Of course, the most effective way to reduce fine dust is to limit the source of emissions. Although there are various sources of fine dust, according to statistics, combustion in the energy industry such as power plants, combustion in manufacturing according to processes in general factories, and combustion in production processes account for 48% of the total emission of fine dust. It is the result of the medium that has undergone the process of burning fuel under high temperature and pressure, such as in an industrial manufacturing plant, discharged through a large chimney.

Nitrogen, sulfur oxides, and carbon particles emitted from the exhaust duct become part of fine dust as they are released, and sulfate and nitrate cause secondary chemical reactions with water vapor or ozone in the exhaust duct or in the air to become fine dust. .

The internal diameter of a general industrial exhaust duct is at the level of 1 to 10 m, and since it is a long form with a length of 10 to 100 m, it is not easy to remove fine dust.

Conventionally, as a method for removing fine dust from such an exhaust duct, a multi-stage filter is configured on the exhaust path of the exhaust duct, or additional facilities for reducing pollutants such as a scrubber are installed. If there is not enough room, it is difficult to apply, and there is a problem in that the cost of constructing and operating additional facilities is excessively required.

Therefore, a method for solving these problems is required.

Korean Patent No. 10-1457421

The present invention is an invention devised to solve the problems of the prior art, so that fine dust contained in exhaust gas discharged from various exhaust ducts including industrial large exhaust ducts can be aggregated and removed by using an audible frequency band. It has an object to provide an exhaust gas fine particle agglomeration treatment apparatus.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

The exhaust gas fine particle aggregation treatment apparatus including the acoustic vibration system of the present invention for achieving the above object is acoustic vibration for agglomerating the fine particles included in the exhaust gas flowing through the exhaust path in the exhaust duct and collecting the dust and a system, wherein the acoustic vibration system is provided in a peripheral region of the exhaust duct and emits an audible sound of a preset wavelength in the form of a plane wave to form a nodal plane having a predetermined standing wave ratio in the discharge path and an acoustic radiation module for cohesively distributing the fine particles contained in the exhaust gas.

In addition, the acoustic radiation module may include a vibrating plate having a predetermined area and fixed to a peripheral region of the exhaust duct, and a main vibrator provided in a central portion of the vibrating plate to emit audible sound of a first wavelength.

In this case, the acoustic radiation module may further include a plurality of auxiliary vibrators provided on the periphery of the main vibrator to supplement the acoustic field of the main vibrator.

Here, the auxiliary vibrator may be disposed in a line symmetrical form with respect to the main vibrator.

In addition, a plurality of the acoustic radiation modules may be arranged in series along the longitudinal direction of the exhaust duct.

In addition, the acoustic vibration system may further include a reflection structure provided on the opposite side of the acoustic radiation module around the exhaust duct to reflect the audible sound emitted from the acoustic radiation module to assist in forming a plane wave.

In this case, the reflective structure may be formed in any one of a rigid wall or a wall including an acoustic metamaterial.

In addition, the acoustic vibration system may include at least one pair of the acoustic radiation modules, and the pair of acoustic radiation modules may be provided at opposing positions around the exhaust duct to form one module set.

In addition, a plurality of the module sets may be provided on the cross-section of the exhaust duct.

On the other hand, the acoustic vibration system is provided in the downstream region of the exhaust duct, the absorption and collection unit for sucking and collecting fine particles in a state in which they are not aggregated and settled among the fine particles included in the exhaust gas flowing through the exhaust path. may include more.

Exhaust gas fine particle agglomeration treatment apparatus including an acoustic vibration system of the present invention for solving the above problems, the fine particles contained in the exhaust gas flowing along the exhaust path of the exhaust duct using a plane wave beam of an audible sound range It has the advantage of being able to effectively agglomerate so that it can be removed on a large scale.

In particular, since the acoustic vibration system of the present invention can be installed in a very narrow space, it can be easily applied even when there is not enough space, as well as minimized the cost required for the construction and operation of additional facilities. there are advantages to

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a view showing a state in which an exhaust gas fine particle agglomeration treatment apparatus according to a first embodiment of the present invention is applied to an exhaust duct;
Figure 2 is a view showing the appearance of the acoustic radiation module in the exhaust gas fine particle agglomeration processing apparatus according to the first embodiment of the present invention;
3 is a view showing a state of aggregating fine particles of exhaust gas through the exhaust gas fine particle agglomeration processing apparatus according to the first embodiment of the present invention;
4 is a finite element method (FEM) simulation result regarding the movement of fine particles over time when plane wave radiation is performed by an acoustic radiation module in the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention; a drawing showing;
FIG. 5 is a view showing a state in which, in the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention, the fine particles in a state of being aggregated and not settling are sucked and collected through the absorption and collection unit;
6 is a view showing another form of an acoustic radiation module in the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention;
7 is a view showing another form of an acoustic radiation module in the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention;
8 is a view showing a state of aggregating the fine particles of the exhaust gas through the exhaust gas fine particle aggregation treatment apparatus according to the second embodiment of the present invention; and
9 is a view showing a state of aggregating the fine particles of the exhaust gas through the exhaust gas fine particle aggregation treatment apparatus according to the third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention in which the object of the present invention can be specifically realized will be described with reference to the accompanying drawings. In describing the present embodiment, the same names and the same reference numerals are used for the same components, and an additional description thereof will be omitted.

1 is a view showing a state in which the exhaust gas fine particle agglomeration treatment apparatus according to the first embodiment of the present invention is applied to the exhaust duct 10 .

As shown in FIG. 1, the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention aggregates the fine particles contained in the exhaust gas flowing through the exhaust path S in the exhaust duct 10, and an acoustic vibration system for dust collection processing, wherein the acoustic vibration system includes an acoustic radiation module (100).

The acoustic radiation module 100 is provided in a region on one side of the circumference of the exhaust duct 10, and radiates an audible sound of a preset wavelength in the form of a plane wave to have a predetermined standing wave ratio in the exhaust path S. ) to form a cohesive distribution of the fine particles contained in the exhaust gas.

In this embodiment, the front surface of the acoustic radiation module 100 faces the inside of the exhaust duct 10 and contains fine particles and is exposed to hot and poisonous exhaust gas, and the rear surface is a rear surface made of general air and a sound-absorbing layer. It has a structure that is placed in space.

In particular, in this embodiment, the acoustic radiation module 100 emits audible sound having a long wavelength to the exhaust path S of the exhaust duct 10, which is constant from the acoustic radiation module 100. A standing wave field between two points is formed by interference with sound reflected from a wall spaced apart.

Accordingly, fine particles are collected in 1 to 3 nodal planes created by the minimum acoustic pressure in the sound field, and since the small nodal plane area has a high particle velocity, collisions between fine particles and According to the bonding, it grows and solidifies by bonding to itself by physical/chemical/electrostatic mutual attachment.

Therefore, the fine particles flowing through the discharge path S of the exhaust duct 10 may be aggregated and settled by their own weight, or other post-treatment methods may be used to treat the agglomerated fine particles.

At this time, the exhaust duct 10 may be modeled as a circular or rectangular pipe in which the exhaust gas flow exists, and in this embodiment, the shape of the exhaust duct 10 is illustrated as having a rectangular cross-section.

2 is a view showing the appearance of the acoustic radiation module 100 in the exhaust gas fine particle agglomeration processing apparatus according to the first embodiment of the present invention.

As shown in FIG. 2 , in this embodiment, the acoustic radiation module 100 has a predetermined area and includes a vibrating plate 110 fixed to a peripheral area of the exhaust duct 10 and the vibrating plate ( The main vibrator 120 provided in the central part of 110 and emitting an audible sound of the first wavelength, and a plurality of main vibrators provided at the periphery of the main vibrator 120 to complement the acoustic field of the main vibrator 120 It has a form including two auxiliary vibrators 130 .

In this embodiment, in order to effectively radiate sound waves of audible frequency in a large area within the wall surface of the exhaust duct 10 without exposing the vibrator itself, a large main vibrator 120 is attached to the rear surface of the central part of the vibration plate 110 . The vibration plate 110 is formed to vibrate with a piston of the same phase at a design frequency to form a standing wave.

At this time, in the sound emitted from the acoustic radiation module 100, all radiation energy is not used to form a standing wave due to diffraction, unless the size of the wall surface of the exhaust duct 10 is equal to the size of the wall surface of the exhaust duct 10. does not increase in intensity.

Therefore, in order to overcome this in the case of this embodiment, the auxiliary vibrator 130 that is additionally provided together with the main vibrator 120 on the rear surface of the vibrating plate 110 and is driven by control is attached to multiple attachments to control them. The radiated sound is emitted as a plane wave.

And, in the present embodiment, the auxiliary vibrator 130 has a form arranged in a line symmetrical form with respect to the main vibrator 120 as a center, but this is not limited to this embodiment only.

Here, the input signal of each vibrator for realizing a specific target radiation acoustic field of the acoustic radiation module 100 can be obtained as a solution of an inverse problem composed of a transfer function between the vibrator and the acoustic field. The corresponding transfer function is defined as the product of two transfer functions between the exciter-vibration field and the vibration field-acoustic field, and the inverse problem determinant formed therefrom can be expressed as the following two equations.

And if Pseudo-Inverse is applied to the above determinant,

to obtain the input signal of each vibrator.

In addition to the above method, a signal obtained based on a transfer function between an exciter-vibration field or an oscillation field-acoustic field may be utilized as an input signal of an exciter.

In addition, in the present embodiment, the acoustic radiation module 100 has a form in which a plurality of them are arranged in series along the longitudinal direction of the exhaust duct 10 . This is to form a long section parallel to the axial direction of the length of the exhaust duct 10 with an effective standing wave ratio.

The array of acoustic radiation modules 100 arranged in series can be considered as a situation in which multiple sound sources exist, and sound waves emitted from adjacent sound sources interfere with each other by the Huygens' Principle to form a plane wave when proceeding over a certain distance. .

That is, the array of acoustic radiation modules 100 arranged in series can stably implement a long standing wavelength in the longitudinal direction of the exhaust duct 10 by using a wave field synthesis method.

At this time, when the internal area of the exhaust duct 10 is not constant with respect to the longitudinal axis direction, the cut surfaces can be formed on the same line as each acoustic radiation module 100 arranged in series radiates different frequencies calculated in advance. can make it

3 is a view showing a state of aggregating the fine particles of the exhaust gas through the exhaust gas fine particle agglomeration processing apparatus according to the first embodiment of the present invention.

As described above, the cross-section of the exhaust duct 10 in this embodiment is formed in a rectangular shape, and these four surfaces have a first surface 11, a second surface 12, and a third surface, respectively, for convenience of description below. The surface 13 and the fourth surface 14 will be referred to.

And as shown in FIG. 3, in the acoustic vibration system of this embodiment, the acoustic radiation module 100 is provided on the first surface 11 and the second surface 12 perpendicular to each other among the circumferences of the exhaust duct 10, respectively. have a form

In addition, on the third surface 13 and the fourth surface 14, which are opposite sides of each of the acoustic radiation modules 100, reflect the audible sound emitted from the acoustic radiation module 100 to form a reflective structure that assists in forming a plane wave. may be provided. Here, the reflective structure may be the wall itself, or a module to which a separate reflective structure is applied.

And, when the reflective structure is a wall, it may be in the form of a rigid wall or a wall including an acoustic metamaterial, and when the reflective structure is in the form of a module, it may be in the form of a structure made by topology and geometry optimization.

4 is an FEM (Finite Element Method) for the movement of fine particles over time when plane wave radiation is performed by the acoustic radiation module 100 in the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention. ) is a diagram showing the simulation results.

According to the above principle, as shown in FIG. 4, the fine particles are aggregated on the cut surface, and as the weight of the particle flocs increases according to the aggregation, and the weight of the particles becomes greater than the drag force, the aggregated fine particles are collected in the exhaust duct 10 sinks to the bottom of

If there is a component that does not settle by its own weight, since such components are already localized and gathered in a narrow area, it is provided in the downstream area of the exhaust duct 10 as shown in FIG. 5, and the discharge path S ) of the fine particles contained in the exhaust gas flowing through the agglomerated fine particles in a non-settling state can be collected through the absorption collection unit 200 that suctions and collects.

Meanwhile, FIG. 6 is a view showing another form of the acoustic radiation module 100 in the exhaust gas fine particle aggregation treatment apparatus according to the first embodiment of the present invention, and FIG. 7 is the exhaust gas according to the first embodiment of the present invention. In the gas fine particle aggregation processing apparatus, it is a view showing another form of the acoustic radiation module (100).

The acoustic radiation module 100 may be of a type in which only the main vibrator 120 is mounted as shown in FIG. 6, or may have a form in which only the auxiliary vibrator 130 is provided as shown in FIG. .

Hereinafter, another embodiment of the present invention will be described.

8 is a view showing a state of aggregating the fine particles of the exhaust gas through the exhaust gas fine particle aggregation treatment apparatus according to the second embodiment of the present invention.

In the case of the second embodiment of the present invention shown in FIG. 8 , the acoustic radiation module 100 is provided on the first surface 11 and the second surface 12 of the exhaust duct 10 , and the third surface 13 . The point in which the reflective structure is applied is the same as in the first embodiment described above.

However, in this embodiment, as the acoustic radiation module 100 is further provided on the fourth surface 14, the acoustic radiation module 100 of the second surface 12 and the acoustic radiation module 100 of the fourth surface 14 ( 100) is provided at positions opposite to each other to form one module set.

That is, in the acoustic vibration system of the present embodiment, a pair of acoustic radiation modules 100 may be provided at opposing positions among the circumferences of the exhaust duct 10 to form one module set.

When the acoustic radiation module 100 is provided at positions opposite to each other, the same standing wave, but a stronger standing wave ratio is generated. In such a standing wavelength, particles are collected in 1 to 3 intercepts or 1 to 6 intersecting lines generated by the minimum acoustic pressure in space, and the small intersections or intersecting lines have the highest particle velocity in the lateral direction. Since it is a high place, the spacing between particles becomes very narrow and collisions occur.

_{At this time, the acoustic radiation force F rad} received by the particles existing in the fluid passage in the sound field is expressed as follows.

Here, a is the radius of the particle, k ₀ is the wave number, y is the distance perpendicular to the wall to which the acoustic radiation module 100 is attached, and the acoustic energy.

It is expressed as , where κ _s is the compressibility of the particle, and P _a is the sound pressure.

Here, the acoustic contrast factor is

It is expressed as , which is a function of the elastic modulus and density ratio of the particle and the medium, and the larger the acoustic contrast ratio, the greater the acoustic radiation force acts on the particle.

And the drag force F _D by the fluid also acts on the particle, and it is expressed as follows.

The drag F _D is a value that remains almost constant when the flow velocity and particle size change are small, and the motion of the particles can be expressed as follows.

That is, in the vicinity of the anti-nodal plane of the standing wave, the particles move toward the plane with a greater acceleration, and the weight of the larger particle, Floc, generated by the aggregation of fine particles increases, so that its own weight is greater than the drag force. When it becomes large, it sinks down the exhaust duct 10 .

9 is a view showing a state of aggregating the fine particles of the exhaust gas through the exhaust gas fine particle aggregation treatment apparatus according to the third embodiment of the present invention.

In the case of the third embodiment of the present invention shown in Fig. 9, the acoustic radiation module 100 is provided on both the first surface 11 to the fourth surface 14 of the exhaust duct 10, and the acoustic radiation opposite to each other is provided. A plurality of module sets constituted by the module 100 are provided on the cross section of the exhaust duct 10 .

In this way, when the acoustic radiation module 100 is provided on all surfaces of the exhaust duct 10 to generate a standing wavelength by generating acoustic radiation, a more powerful cutting line can be formed.

As described above, preferred embodiments according to the present invention have been described, and the fact that the present invention can be embodied in other specific forms without departing from the spirit or scope of the present invention in addition to the above-described embodiments is one of ordinary skill in the art. It is obvious to them. Therefore, the above-described embodiments are to be regarded as illustrative rather than restrictive, and accordingly, the present invention is not limited to the above description, but may be modified within the scope of the appended claims and their equivalents.

10: exhaust duct
S: discharge path
100: acoustic radiation module
110: vibration plate
120: main vibrator
130: auxiliary vibrator
200: absorption collection unit

Claims (10)

In the exhaust gas fine particle aggregation treatment apparatus comprising an acoustic vibration system for collecting and collecting fine particles contained in the exhaust gas flowing through the exhaust path in the exhaust duct,
The acoustic vibration system,
It is provided in one area around the periphery of the exhaust duct and emits audible sound of a preset wavelength in the form of a plane wave to form a nodal plane having a predetermined standing wave ratio in the exhaust path to cohesively distribute the fine particles included in the exhaust gas. Including an acoustic radiation module to let
Exhaust gas fine particle agglomeration treatment device. According to claim 1,
The acoustic radiation module,
a vibrating plate having a predetermined area and fixed to a peripheral area of the exhaust duct; and
a main vibrator provided in the central portion of the vibrating plate for emitting an audible sound of a first wavelength;
containing,
Exhaust gas fine particle agglomeration treatment device. 3. The method of claim 2,
The acoustic radiation module,
Further comprising a plurality of auxiliary vibrators provided on the periphery of the main vibrator to complement the acoustic field of the main vibrator,
Exhaust gas fine particle agglomeration treatment device. 4. The method of claim 3,
The auxiliary vibrator is disposed in a line symmetrical form with respect to the main vibrator,
Exhaust gas fine particle agglomeration treatment device. According to claim 1,
A plurality of the acoustic radiation modules are arranged in series along the longitudinal direction of the exhaust duct,
Exhaust gas fine particle agglomeration treatment device. According to claim 1,
The acoustic vibration system,
Further comprising a reflective structure provided on the opposite side of the acoustic radiation module in the circumference of the exhaust duct to reflect the audible sound emitted from the acoustic radiation module to assist in forming a plane wave,
Exhaust gas fine particle agglomeration treatment device. 7. The method of claim 6,
The reflective structure is
Formed in any one of a rigid wall or a wall containing an acoustic metamaterial,
Exhaust gas fine particle agglomeration treatment device. According to claim 1,
The acoustic vibration system,
at least one pair of the acoustic radiation modules, wherein the pair of acoustic radiation modules are provided at opposite positions among the circumferences of the exhaust duct to form one module set,
Exhaust gas fine particle agglomeration treatment device. 9. The method of claim 8,
The module set is provided in plurality on the cross-section of the exhaust duct,
Exhaust gas fine particle agglomeration treatment device. According to claim 1,
The acoustic vibration system,
It is provided in the downstream region of the exhaust duct, further comprising an absorption and collection unit for sucking and collecting fine particles in a state in which the fine particles are not aggregated and settling among the fine particles included in the exhaust gas flowing through the discharge path,
Exhaust gas fine particle agglomeration treatment device.

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