JP2002263604A - Process and system for removing suspended dust - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suspended dust removal process for efficiently capturing fine dust suspended in the air and allowing the captured dust to fall and also to provide a system for the process. SOLUTION: This suspended dust removal process involves spraying an aqueous solution containing at least a surfactant, on dust suspended in air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a system for removing dust, particularly dust that floats in the air and hardly falls. Specifically, in working environments where invisible fine dust floats, such as in waste treatment plants, fine powder handling factories, coal mines, etc., fine mist particles containing surfactant etc. are sprayed on the floating dust, The present invention relates to a method of catching and dropping dust and a system thereof.

[0002]

2. Description of the Related Art In a work environment where a large amount of dust is generated,
Fine dust (having a particle size of less than about 10 microns) harmful to the human body is suspended in the air, and various efforts have been made to reduce the fine dust. For example, there is a method in which an operator wears a dust mask, collects fine dust with a dust collector, sprays water on fine dust with a general watering nozzle, or sprays fine mist onto fine dust.

[0003] In the dust mask method, a worker wearing the mask suffers from mental and physical pains such as breathlessness and discomfort. In the dust collector collection method, enormous costs and costs are required due to investment in large-scale facilities, running costs, periodic maintenance, etc., in order to suck dust floating in a wide space. Further, in the water spraying method, water droplets discharged from a general watering nozzle are of a very large size, and the water droplets have little chance of colliding with the fine dust, so that they are not effective in capturing fine dust.

Japanese Unexamined Patent Publication No. Hei 11-343746 discloses a method and an apparatus for removing suspended dust, which uses a high-pressure pump and a nozzle to produce mist particles having a particle diameter of about 5 to 30 microns composed of water alone and spray them onto the suspended dust. Is disclosed. In this method, ordinary water is used as the spray liquid.
Generally, fine dust particles floating in the air have a large surface tension and have water repellency to repel water (so-called poor wettability). Therefore, even if the mist particles made of ordinary water collide with the fine dust, it is repelled by the fine dust and it is difficult to capture the fine dust.

[0005] Further, since the mist particles are extremely fine particles having a size of 30 microns or less, there is a problem that the mist particles are suspended in the air forever without falling, and obstruct the field of view of the operator.

[0006] In addition, since mist particles composed of ordinary water have a poor collection efficiency of fine dust, it is necessary to spray a large amount of water, so that there is a problem that peripheral equipment and floor surfaces are inadvertently wetted. is there.

Further, in the nozzle for spraying the mist of fine particles, since the diameter of the orifice is very small, there is a problem that the foreign matter contained in the fluid is clogged in a relatively short time.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method and a system for removing suspended dust that efficiently captures fine dust suspended in the air.

[0009]

In order to solve the above technical problem, the present invention is characterized in that an aqueous solution containing at least a surfactant is sprayed on dust floating in the air. The present invention provides a method for removing suspended dust.

[0010] By using a spray aqueous solution containing at least a surfactant, the surface tension of the spray aqueous solution is greatly reduced, and the spray aqueous solution is easily wetted by floating fine particles (having a particle size of approximately less than 10 microns). It becomes easy to adapt. Therefore, when the mist particles of the spray aqueous solution containing the surfactant collide with the suspended fine dust, the fine dust is captured by the mist particle containing the surfactant, and the capturing efficiency of the fine dust is improved.

Further, since fine dust can be efficiently captured, a small amount of spray aqueous solution can be used.
Unnecessary wetting of peripheral equipment and floor surfaces is prevented.

Further, since the spray liquid contains a surfactant, the spray liquid is less likely to evaporate than ordinary water, so that the soaking of the floor surface due to the wind generated when people or vehicles move around is prevented.

Further, since the spray liquid contains a surfactant, foreign substances clogged in the orifice of the nozzle can easily flow and clogging of the nozzle can be prevented.

The surfactant is preferably an anionic surfactant, such as sodium salts of anionic alpha-olefin sulfonic acid, sodium salt of linear alkyl benzene sulfonic acid, sodium salt of lauryl sulfate, and nonionic polyoxysulfonic acid. Ethylene alkyl ether is used. Particularly preferred are alpha olefin sulfonic acid sodium salts which are inexpensive and mild to the skin and eyes. The amount of the surfactant added to water is preferably 0.1 to 0.2% by volume.

In general, fine dust has a unique unpleasant smell because it is highly active due to fine particles and easily adsorbs odorous components. Therefore, the spray liquid preferably contains a deodorant. Examples of the deodorant include “Saniclean (registered trademark) series” (Saniclean Q-100, Q-110, Q-300, Q-4) which is a plant component system manufactured by Organo Corporation.
00, Q-410, Q-420, Q-500, Q-51
0) etc. are used. Further, the amount of the deodorant added to water is preferably 0.5 to 10% by volume.

Preferably, the size of the mist particles is 20 to 15
0 microns. By setting the fog particles to such a size, the fog particles density per unit volume in the space in which the fine dust floats increases, and the chance (number of times) that the fog particles collide with the fine dust increases. Increase. Also,
For example, even if the mist particles are smaller than 50 microns, the mist particles surely capture the fine dust, so that the two easily coalesce and become larger than the original mist particles, and the weight of the dust capture mist particles is reduced. Heavier. Therefore, the dust trapping fog particles are easily dropped, and it is less likely that the dust trapped fog particles float in the air and hinder the field of view of the operator, such as “mist”.

The aqueous solution containing a surfactant can be sprayed from below or upward or from the side. Preferably, the aqueous solution containing a surfactant is sprayed from above and from the surroundings in a building where dust is generated. I do. This prevents the fine dust that is to be diffused upward and laterally from being trapped and dropped by the mist particles containing the surfactant, and prevents the fine dust from diffusing around the dust generation source.

Further, at the opening of the building where dust is generated, the aqueous solution is sprayed in a curtain shape from above to below or from one side to the other side, and the opening is formed by curtain-shaped mist particles. Close. This prevents the fine dust to be diffused from the opening of the building from being captured and dropped by the mist particles containing the surfactant, and prevents the fine dust from diffusing to the outside of the building.

Further, the present invention provides a suspended dust removing system for performing the above method.

That is, the suspended dust removal system comprises a spray liquid preparation means for mixing water and a surfactant to prepare a spray aqueous solution, a spray means for spraying the spray aqueous solution into mist particles, and a spray amount and a spray time. Control means for controlling.

According to the above configuration, the spray aqueous solution containing the surfactant is sprayed from the spray means in a predetermined amount and for a predetermined time. Then, the mist particles collide with the fine dust floating in the air, so that the fine dust can be efficiently captured and dropped.

As the spraying means, it is possible to use an ink jet head (piezoelectric element type or microbubble type) which is often used in an ink jet printer, in which a large number of components are arranged in a matrix. A spray nozzle that can generate a large amount of fine fog particles and sprays fog with a low-pressure gas is preferable. Low-pressure gas is a pressure of 2 to ⁷ kg / cm ³ , preferably ^{3 to 5} kg.
/ Cm ³ gas, such as air or nitrogen.

As the spray nozzle, a one-fluid nozzle can also be used. However, a two-fluid nozzle capable of relatively freely controlling the mist particle size by adjusting the pressure and flow rate of the delivery air and spray liquid and capable of further atomization than 50 microns is preferred.

Preferably, there is further provided a moving means for appropriately moving the spraying means. According to the above configuration, even if the dust generation location changes with time, the fine dust can be captured by moving the spraying means to the dust generation location. Therefore, the installation place of the pipe connected to the spraying means is reduced, and the installation cost is reduced.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A floating dust removal system according to the present invention will be described below with reference to the accompanying drawings.

First, a floating dust removal system according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an explanatory view showing a suspended dust removal system according to the present invention, and FIG. 2 is a piping connection configuration diagram of the suspended dust removal system of FIG.

The suspended dust removal system includes a storage box 10 in which various devices for supplying an aqueous spray solution are stored.
And the spray device 40 installed above the work building 50
And a pipe 30 connecting between the storage box 10 and the spray device 40.

The storage box 10 has a low pressure (2 to 7 kg).
/ Pressure of cm ^3, preferably the main body apparatus 14 for supplying the compressor 12 which generates a compressed air 3-5 kg / cm ^3), the conditioned air and spray solution at a predetermined pressure and flow rate, the filter 28 A water pressure adjusting device 16 that stores the water that has passed through the tank and a control device 18 that controls the operation of the entire removal system are stored. Note that the compressor 12 can be arranged outside the storage box 10.

The main unit 14 has a tank 23 for mixing water and a chemical (such as a surfactant and a deodorant) at a predetermined ratio.
And a pump 21 for constant rate or fixed quantity measurement, and a flow meter 24 for measuring the flow rate of the mixed spray aqueous solution and the delivery air.
A valve 22 for manually opening and closing the valve, a solenoid valve 26 for automatically opening and closing the valve, and a siphon check valve 25 for preventing the backflow of the liquid. These members are controlled by the control device 18 described above.

As the chemical solution, a surfactant, a deodorant, etc.
A variety of drugs can be used whose properties are not affected by the presence of other components.

The pipe 30 is composed of an air pipe 32 for supplying a relatively low pressure delivery air and a spray liquid pipe 34 for supplying a spray solution. The air pipe 32 and the spray liquid pipe 34
Each is branched into several systems on the way according to the arrangement of the spray device 40 (in FIG. 2, the system is branched into two systems). In addition, the spray nozzle 4
2 in case of clogging with garbage etc. and for freezing in winter,
The drain pipe 36 is connected.

The spraying device 40 is a plurality of spraying nozzles (two-fluid nozzles) 42 connected in series or in parallel to the terminal side of the pipe 30, and is connected to the pipe 30 extending from the main unit 14. In addition, a plurality of spraying devices 40 are arranged at locations to be sprayed via support arms 53 extending from the ceiling 52 of the working building 50. By providing the flexible joint 27 in the middle of the pipe 30, the spraying device 40 can move in a stretchable manner. In addition,
The spray nozzle 42 may be a one-fluid nozzle if relatively large mist particles of about 100 microns are sufficient. However, a two-fluid nozzle is preferred, in which the size and size of the mist particles can be controlled relatively freely by adjusting the pressure and flow rate of the delivery air and the spray liquid, and the mist particles can be further refined to less than 50 microns.

The spray aqueous solution containing the chemical solution and the low-pressure compressed air are respectively fed by the pipe 30 and merged just before the outlet of the spray nozzle 42, whereby fine mist particles are ejected downward from the spray nozzle 42. As a result, a conical spray zone 90 extending downward from the two-fluid spray nozzle 42 is formed so as to cover the dust floating space 56 inside the work building 50, and the floating fine dust (having a particle size of approximately 10 microns) is formed. Smaller) are captured by the fine mist particles and fall.

In the above-described embodiment, the spray aqueous solution is sprayed downward from above, but the spray aqueous solution is sprayed upward from below, obliquely downward, or obliquely upward from below. You can also.

Next, a floating dust removal system according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a plan view when the suspended dust removal system according to the present invention is applied to a dust generation factory, and FIG.
FIG.

In the second embodiment, as a more specific embodiment, aggregate loaded on a shovel 72 of a shovel loader 70 is put into a hopper 74 in an asphalt mixture factory 50 and placed under the hopper 74. The state in which the aggregate is transferred to the next mixture process by the belt conveyor 78 is shown. Therefore, when the aggregate is transferred from the shovel 72 to the hopper 74, a large amount of fine dust is generated, and a dust floating space 56 in which the fine dust floats is formed inside the work building 50 in a relatively closed state. .

The structure is substantially the same as that of the first embodiment, but the two first spray nozzles 42 and the second spray nozzles 44 each surround one hopper 74 which is a source of fine dust. The difference is that it is arranged on the ceiling 52 of the building 50 and that the spray nozzle 46 for conveyor is additionally arranged near the outside of the discharge port 76 that guides the aggregate dropped from the hopper 74 to the belt conveyor 78. ing.
Then, by connecting the first spray nozzle 42 and the second spray nozzle 44 to the pipe 30 of another system, it is possible to arbitrarily change the mist particle size, the spray amount, the spray timing, the properties of the spray liquid, and the like.

According to the above configuration, the spray aqueous solution containing the chemical is ejected downward (in the direction of the spray direction a) toward the hopper 74 from the first spray nozzle 42 and the second spray nozzle 44, whereby The mist particles collide with the fine dust diffused around, and the fine dust is captured by the mist particles and falls. As a result, the fine dust floating around the hopper 74 is removed.

The effect of the floating dust removal system according to the present invention was quantitatively confirmed by the following method. That is, 2 liters of water per minute, 600 liters of air
As a chemical solution, an aqueous solution of a spray of anionic alpha sodium sulfonate was sprayed from the two first spray nozzles 42 and the second spray nozzles 44 at a rate of 0.2 liter / hour. Then, using a light scattering type high-sensitivity digital dust meter (Model 3423) manufactured by Nippon Kagaku Kogyo, the number of one-minute counts of fine particles of 10 μm or less floating in the air was measured. As a result, the average concentration of fine dust cpm (relative concentration expressed by counting for one minute) is about 745 cpm before spraying of the spray aqueous solution and about 64 cpm after spraying. Therefore, by spraying the spray aqueous solution containing the chemical solution, the concentration of the fine dust smaller than approximately 10 microns and the concentration of the larger dust in the working building 50 were significantly reduced.

Next, a floating dust removal system according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a plan view when the suspended dust removal system according to the present invention is applied to a dust generation factory, and FIG.
FIG.

In the third embodiment, similarly to the above-described second embodiment, the aggregate loaded on the shovel 72 of the shovel loader 70 in the asphalt mixture factory 50 is subjected to a series of hoppers 74 (four hoppers in the figure). ) Is shown, and the aggregate is transported to the next composite material process by the belt conveyor 78 arranged therebelow.

The configuration is substantially the same as that of the second embodiment, except that a plurality of hoppers 74, which are sources of fine dust, are arranged in series. The difference is that the source of dust changes. The worker 80 has a remote control transmitter 82 for control, and a remote control receiver 84 for receiving a command from the remote control transmitter 82 is installed. Therefore, when the operator 80 operates the remote control transmitter 82, the location where the aqueous spray solution is sprayed from the first spray nozzle 42 and the second spray nozzle 44 fixed to the ceiling 52 of the working building 50, the size of the mist particles, The spray amount, spray timing, properties of the spray aqueous solution, and the like can be changed. Further, for example, a guide rail (not shown) may be provided inside the ceiling 52 of the work building 50, and wheels may be provided in the spray device 40, so that the spray device 40 can be moved along the guide rail. . In this case, as shown in FIG. 5, the worker 80 operates the remote control transmitter 82 to move the spraying device 40 to a place to be sprayed.

According to the above configuration, since the spray aqueous solution is sprayed to a necessary and sufficient spray place, the consumption of the spray aqueous solution and the compressed air can be suppressed. Further, by spraying not only on the hopper 74 which is a direct source of the fine dust but also on the hoppers 74 on both sides thereof,
The fine dust floating in the internal space of the work building 50 can be more effectively captured and dropped.

A floating dust removal system according to a fourth embodiment of the present invention will be described with reference to FIG.

FIG. 7 is an explanatory view showing a suspended dust removing system according to the present invention, and is configured substantially in the same manner as in the first embodiment. An opening 60 for a person or a vehicle to enter or exit from the side wall 54 of the work building 50 where fine dust is generated is usually provided. Fine dust generated inside the work building 50 diffuses from the opening 60 to the outside, and deteriorates the surrounding environment of the work building 50. Therefore, the difference is that the shutter 58 with the spray device 40 is installed above the opening 60 in order to prevent the outside diffusion of the fine dust from the opening 60. That is, one or more spray nozzles 42 are arranged above the opening 60. Along with that, one or more spray nozzles 42 can be arranged on both sides of the opening 60 or on one side. When the spray aqueous solution containing the chemical solution is sprayed from each spray nozzle 42, a spray curtain is formed in the opening 60, and the fine dust is prevented from diffusing outward from the opening 60.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a suspended dust removal system according to a first embodiment of the present invention.

FIG. 2 is a piping connection configuration diagram of the floating dust removal system of FIG. 1;

FIG. 3 is a plan view when a suspended dust removal system according to a second embodiment of the present invention is applied to a dust generation factory.

FIG. 4 is a side view of FIG. 3;

FIG. 5 is a plan view when a suspended dust removal system according to a third embodiment of the present invention is applied to a dust generation factory.

FIG. 6 is a front view of FIG. 5;

FIG. 7 is an explanatory diagram showing a suspended dust removal system according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Storage box 12 Compressor 14 Main unit 16 Water pressure regulator 18 Controller 21 Pump 22 Valve 23 Chemical tank 24 Flow meter 25 Siphon check valve 26 Solenoid valve 27 Flexible joint 30 Pipe 32 Air pipe 34 Spray liquid pipe 36 Drain pipe 40 Spray Apparatus 42 First spray nozzle 44 Second spray nozzle 46 Conveyor spray nozzle 50 Working building 52 Ceiling 53 Support arm 54 Side wall 56 Dust floating space 58 Shutter 60 Opening 70 Shovel loader 72 Shovel 74 Hopper 76 Discharge port 78 Belt conveyor 80 Work Person 82 Remote control transmitter 84 Remote control receiver 90 Spray zone a Spray direction

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3B117 AA01 AA03 BA44 BA51 4C080 AA03 BB02 BB10 CC02 CC12 HH03 KK06 KK08 LL04 LL13 MM31 NN01 QQ01 4D032 AC01 CA01 DA01 4F035 AA04 BA03 BA06 BA07 BA22

Claims (10)

[Claims] 1. An aqueous solution containing at least a surfactant,
A method for removing floating dust, comprising spraying dust floating in the air, capturing the floating dust with mist particles, and dropping the dust. 2. The method for removing suspended dust according to claim 1, wherein the surfactant is an anionic surfactant. 3. The method for removing suspended dust according to claim 1, wherein the spray aqueous solution further contains a deodorant. 4. The method of claim 1, wherein the size of the mist particles is 20 to 150 microns. 5. In a building where dust is generated, the aqueous solution is sprayed from above and from the surroundings.
The method for removing suspended suspended dust according to claim 1. 6. An opening of a building where dust is generated,
The floating dust according to claim 1, wherein the aqueous solution is sprayed from above to below or from one side to the other side in a curtain shape, and the opening is closed by curtain-like mist particles. Removal method. 7. A spray liquid preparation means for preparing a spray aqueous solution by mixing water and a surfactant, a spray means for jetting the spray aqueous solution into mist particles, and a control means for controlling a spray amount and a spray time. A floating dust removal system comprising: 8. The system for removing suspended dust according to claim 7, wherein the spraying means is a spray nozzle for spraying the spray aqueous solution with a low-pressure gas. 9. The spray nozzle according to claim 1, wherein the spray nozzle is a two-fluid nozzle for ejecting a spray aqueous solution with a low-pressure gas.
An airborne dust removal system according to claim 8. 10. The floating dust removal system according to claim 7, further comprising a moving means for appropriately moving said spraying means.