JP2011127851A - System for replacing filter of exhaust passage including function for preventing scattering of fine particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system capable of replacing an air filter without scattering fine particles attached to the air filter and its circumference, by moistening the periphery of the replaceable air filter disposed in the exhaust passage by a liquid. <P>SOLUTION: This filter replacement system of the exhaust passage, capable of keeping a filter mounting place for collecting the fine particles in a moist state by liquid supply, includes a connection duct P<SB>1</SB>formed by a cylindrical part at an opening section side of the exhaust passage P, a shielding means A capable of blocking off the connection duct from a remaining exhaust passage part by an air-tight damper, an air filter B for removing the fine particles, detachably connected to a terminal end of the connection duct, and a liquid supplying means C including a supply opening positioned on the connection duct or its neighborhood to wet the entire inner faces of the connection duct, the air-tight damper and the air filter. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a system for exchanging a filter in an exhaust passage, which has a function of preventing scattering of fine particles.

  Powders such as highly bioactive drugs and some nanomaterials float in the air as invisible fine particles, and there is concern that they may harm the human body if exposed to humans by inhalation or contact . Therefore, in order to prevent discharge from facilities handling these powders to the outside environment, a high-performance filter such as HEPA or ULPA is provided at the exhaust port of the air conditioning equipment (see FIG. 1 of Patent Document 1).

  In addition, in order to reduce the exposure risk to workers handling these powders and to prevent cross-contamination between different products, it is necessary to take measures to prevent the powder handled inside the manufacturing equipment from leaking to the surrounding work environment. A HEPA filter or the like is provided on a dust collector attached to the manufacturing apparatus (see FIG. 3 of Patent Document 2).

  These filters have a capability that decreases with the amount of powder collected, and therefore need to be replaced periodically. However, in order to remove the used filter at the time of replacement, the powder collected by the filter and the powder deposited and deposited in the flow path upstream of the filter are scattered, polluting the manufacturing environment, and replacement workers. May be exposed to powder.

  In order to avoid this danger, it is not sufficient to wear work clothes or the like, and conventionally, the surroundings of the filter to be replaced have been enclosed. For example, it is known that a storage bag is built beside the filter installation location of the air passage of an apparatus that filters air containing harmful particles, and the used filter is wrapped in a bag without being exposed to the outside (patented) Literature 3-4).

  Further, as a normal dust countermeasure, there is known a technique for reducing the frequency of filter replacement by cleaning portions other than the filter installation location of the exhaust duct installed in the indoor parking lot (Patent Document 5).

JP 2002-272827 A JP2008-082696 JP-A-63-66574 JP2007-268495A Japanese Patent Laid-Open No. 06-307067

  In short, Patent Documents 3 to 5 are based on the idea of “removing particles” by wrapping a filter that collects particles or cleaning the particle adhesion surface. However, there are particles that could not be removed except for the place surrounded by the bag or the washed place, and there is a concern about the influence of these particles on the human body.

  The first reason that there are concerns about adverse effects on the human body is that the allowable intake of nanoparticles and particles of pharmaceutical ingredients has not been elucidated, and it is desirable to prevent even a small amount of exposure. Therefore, it is not safe because most of the fine particles in the exhaust passage are removed. The second reason is that the behavior of these fine particles is not visible, and there is a possibility that the fine particles are sucked unprotected because the measuring means is not sufficiently constructed.

  The applicant focused on such circumstances and came up with the idea of mainly taking “measures to prevent the fine particles from scattering” before replacing the filter, which is a particle deposit.

  The first object of the present invention is to replace the air filter so that the air filter and fine particles attached to the periphery of the air filter and the surrounding area are not scattered by moistening the periphery of the replaceable air filter installed in the exhaust passage with a liquid It is to provide a system that can.

  A second object of the present invention is a system for replacing the air filter, wherein an air filter is supplied to an opening of an exhaust passage, and a liquid is supplied to the inside of a connection duct which is a portion of the exhaust passage on the opening side. The purpose is to provide a port that can be cut off from its connecting duct and the remaining exhaust passage part.

  A third object of the present invention is to provide a system for exchanging the air filter, wherein the connection duct has a vertical cylindrical shape with a lower end opening.

First, in the filter replacement system for the exhaust path, the first means is capable of making the filter installation location for collecting fine particles wet with the liquid supply.
A connection duct formed of a cylindrical portion on the opening side of the exhaust path;
Shielding means capable of tightly blocking the connection duct and the remaining exhaust passage portion with a shielding damper;
An air filter for particulate removal, which is detachably connected to the end of the connection duct;
A liquid supply means including a supply port arranged so as to wet the entire inner surfaces of the connection duct, the shielding damper, and the air filter at or near the connection duct;
It comprises.

In this means, as shown in FIG. 1, the connection duct P _{1 in} the vicinity of the replacement filter in the exhaust path P and the remaining exhaust path portion P ₂ can be hermetically blocked, and the connection duct P _{1 as} shown in FIG. It has been proposed that a liquid is fed into the inside so as to make it in a wet state in which fine particles are not easily scattered. The reason for shutting off the connection duct and the remaining exhaust passage part is that the inside of the connection duct is efficiently wetted, and secondly, the fine particles re-scattered from the exhaust passage part other than the connection duct are replaced by a filter. It is to prevent workers from sucking.

  This system is suitable for installation in the exhaust ducts of air conditioning equipment in facilities that handle harmful powders such as highly bioactive drugs and nanomaterials, or in the exhaust equipment of manufacturing equipment such as draft chambers, safety cabinets, and glove boxes. It is a thing.

The “connection duct” is an exhaust path portion that connects the shielding means and the air filter. The “opening” may be either the inlet E _{1 or the} outlet E ₂ shown in FIG. Among “fine particles”, the main target is particles and powders intentionally produced for use in industries such as industry and medicine. Contains nano-sized particles. The “liquid supply means” only needs to have at least a supply port for wetting the inner surface of the connection duct and the air filter.

The second means includes the first means, and the connection duct has a vertical cylindrical shape having an inner surface perpendicular to the lower end, and
The connecting duct portion above the air filter is provided with fixing means capable of fixing the upper end portion of the air filter collection bag so as to wrap the air filter from the outside.

In this section, it proposes to form a connecting duct P ₁ in a vertical cylindrical as shown in FIG. Thereby, an opening part can serve as a filter exchange port and the collection | recovery port of supply water. When the filter replacement port is formed on the side wall of the exhaust passage as in the above-mentioned Patent Documents 3 to 4, there is a possibility that the replacement port is formed with irregularities and dust may be attached, but this means can reduce such inconvenience. The air filter recovery bag can also serve as a supply water recovery bag. As a means for fixing the air filter collection bag, as shown in FIG. 5, a bag attachment edge and a fastener for fastening the air filter collection bag can be provided on the edge of the connection duct.

  The third means includes the second means, and the liquid supply means can supply a certain amount of liquid necessary to wet the entire inner surfaces of the connection duct, the shielding damper, and the air filter. It is configured.

In this section proposes a liquid supply means C for wetting the inside of the connecting duct P ₁ as shown in FIG. It is desirable to provide a controller D that controls the amount of water supplied from the liquid supply means. Water exceeding the amount of water retained on the wetted surface inside the connection duct passes through the air filter and enters the air filter collection bag supported by the fixing means. The supporting force of the fixing means may be provided so as to support at least the weight of a predetermined amount of water supplied by the liquid supply means.

  The fourth means includes either the second means or the third means, and the liquid supply means is configured to spray the liquid from the supply port in almost all directions.

  According to the first aspect of the invention, since the liquid is supplied to the connection duct between the air filter and the shielding damper, the inactivated state in which the fine particles in the connection duct are difficult to scatter.

  According to the invention relating to the second means, since the connecting duct is installed downward and the fixing means for fixing the air filter collection bag is provided, it is necessary to provide a drainage path for the supplied water into the connecting duct. Absent.

  According to the third aspect of the invention, since a predetermined amount of water is supplied to wet the entire inner surfaces of the connection duct, the shielding damper, and the air filter, it is possible to reliably prevent the scattering of fine particles.

  According to the fourth aspect of the invention, since the liquid is sprayed from the supply port almost in all directions, the inside of the connection duct can be evenly wetted with the liquid.

It is the block diagram which applied the system for filter exchange of the exhaust path provided with the fine particle scattering prevention function which concerns on the 1st Embodiment of this invention to the facility which handles nanomaterials. It is the longitudinal cross-sectional view which looked at the system of FIG. 1 from the front direction. FIG. 2 is a longitudinal sectional view from the side of the system of FIG. 1. It is a longitudinal cross-sectional view from the front direction at the time of ventilation of the system of FIG. It is a longitudinal cross-sectional view from the front direction at the time of fountain of the system of FIG. It is a longitudinal cross-sectional view from the front direction at the time of filter removal of the system of FIG. It is a longitudinal cross-sectional view from the front direction of the system for filter replacement | exchange of an exhaust passage provided with the fine particle scattering prevention function which concerns on the 2nd Embodiment of this invention.

  FIG. 1 to FIG. 6 show a system for exchanging a filter in an exhaust passage, which has a function of preventing scattering of fine particles according to the first embodiment of the present invention. 1 to 6, FIG. 1 is a configuration diagram in which the present system is applied to a facility handling nanomaterials, and FIGS. 2 to 4 are explanatory diagrams conceptually showing the relationship between main components of the system. 5 to 6 are explanatory views of the operation of the present system.

In FIG. 1, R ₁ represents a work room of a facility that handles nanomaterials, and R ₂ represents a machine room. It is formed through the exhaust path P to the outside through the machine room R ₂ from the interior of the working chamber. The exhaust path P includes a suction port E ₁ and outlet E ₂ as an opening. A blower fan BL is installed in the exhaust path. These structures are merely examples for explaining the system of the present invention, and the target facility may not be a facility handling nanomaterials, and the machine room may be omitted.

The system according to the present invention includes a connection duct P ₁ , a shielding unit A, an air filter B, a liquid supply unit C, and a control unit D.

Connecting duct P ₁ is an exhaust path portion between the shielding means A and the air filter B, and the illustrated example, constitutes a part of the inlet E ₁ side of the exhaust path P. This is because if the air filter is provided on the suction port side of the exhaust path P, dirt inside the exhaust path P can be reduced. However, it may be a vertical tube portion of the exhaust passage of the outlet E ₂ side as connecting duct. The peripheral wall 2 of this connection duct is formed as a vertical cylinder with a lower end opening. The inner surface 4 of the connection duct is a smooth vertical surface. Connecting duct P ₁ is delimited as the rest of the exhaust path portion P ₂ in shielding damper below, it is not necessary to attach differentiated structure as a passage. Connecting duct P ₁ has a length capable of opening and closing of at least shield the damper, also it is desirable to the inlet E ₁ and length capable of internal cleaning. A viewing window 6 is formed in the upper part of the connection duct.

On the outside of the connecting duct P _1, for example, providing the air filter recovery bag Bg fixing means 8 formed by a plastic. The fixing means 8 in the illustrated example can hold the opening end of the air filter collection bag Bg with a notch edge provided laterally on the outer surface of the peripheral wall 2 of the connection duct and a retaining plate pivoted in the vicinity of the notch edge. However, any structure may be used as long as it has an appropriate fixing force.

  In one preferred embodiment, the air filter recovery bag Bg described above has a function of accumulating water so that water sprayed by the liquid supply means described later does not spill to the floor via the air filter B. This is because if water containing fine particles spills on the floor and dries, the worker may inhale fine particles scattered by drying. In this case, it is preferable that the fixing means 8 has a fixing force enough to support the weight of the amount of water sprayed once so that all of the water sprayed by the liquid supply means may flow into the air filter collection bag. It is.

As shown in FIG. 3, the shielding means A includes a shielding damper 10 and a rotation motor 16. The shielding damper 10, a shielding plate for the lower surface 12 and a flat surface, made by pivotally mounted on pivot shaft 14 which is horizontally provided on the upper end portion of the connecting duct P _1. In the illustrated example, the rotation shaft 14 is attached to the intermediate portion in the width direction of the shielding plate forming the shielding damper, but the rotation shaft 14 may be attached to the end portion of the shielding plate.

The role of the shielding damper 10 is to cut off the connection duct P ₁ of the exhaust path from the remaining exhaust path portion P ₂ in the gas-tight and liquid-tight. By blocking the upper end portion of the connecting duct with a shielding damper 10, as shown in FIG. 5, the spray water below does not flow prior to the installation location of the shielding damper 10, to be spray surface in the connection duct P ₁ Can be wet evenly. Furthermore, it is to avoid scattering of fine particles from the exhaust passage part which is not wet. In the example shown in the figure, an air filter B such as a HEPA filter is provided on the suction port E ₁ side. However, there is a possibility that fine particles collected for various reasons are scattered again in the air and attached to the inner surface of the exhaust passage. is there. For example, this is a case where an external force (for example, seismic force) similar to that when the air filter is removed is applied.

Air filter B is (in the illustrated example inlet E ₁₎ opening of the connecting duct P ₁ are detachably mounted within. This filter can be a high performance filter such as HEPA or ULPA. The HEPA filter has a particle collection rate of 99.97% or more with respect to particles having a particle diameter of 0.3 μm. The filter medium of this HEPA filter is generally made of glass fiber having a diameter of 1 to 10 μm or less, and has a mechanism in which particles are collected on the fiber by the principle of inertia, collision, diffusion, and the like. However, the collected fine particles may re-scatter from the surface of the filter due to an impact such as when the filter is removed. To avoid this, there is a method of pre-wetting with water as follows.

The liquid supply means C is formed by a water supply tank 22, a water supply pump 24, a water supply pipe 26, and a spray nozzle 28 which is a supply port. In the preferred illustrated example, the water supply pipe 26 enters into the connection duct P1, and the spray nozzle 28 is positioned substantially at the center of the connection duct. The role of the spray nozzle 28 is simply to wet the inside of the connection duct 2, and the amount of water sprayed may be smaller than in the case of cleaning the inside of the duct. However, at least we shall sufficiently sprayed to the upper surface 18 of the air filter B, further spraying water to the corners of the shielding damper 10 and the connection duct P ₁ is provided to reach. Moreover, the water pump 24 is configured to be able to feed a certain amount of water.

  The supply port of the liquid supply means C is preferably a spray port, but is not limited thereto. For example, water may ooze out from a part of the connection duct or the vicinity of the connection duct, and the water may flow along the inner surface of the connection duct.

The control unit D controls the rotation motor 16 of the shielding unit A and the water supply pump 24 of the liquid supply unit C. Unlike the example of illustration, you may provide the control part for rotation motors, and the control part for water pumps separately. Control unit D controls the rotation motor 16 to eject the necessary and sufficient amount of water to wet the inside of the connecting duct P _1.

  As a preferred embodiment, the sequence of closing the shielding damper and then spraying water can be incorporated into the control program. In the case of manual operation, when the order of water spraying → closing of the shielding damper 10 is caused by human error, water is sprayed in the state of FIG. 4, and the surface of the shielding damper (in the closed state) This is because the lower surface may not be sufficiently wetted.

In the above configuration, when the shielding damper 10 is opened and the blower fan BL installed in the exhaust path P is operated, fine particles mainly adhere to the air filter BL from the air being blown. The shielding damper is closed, by using a fixing means 18, mounting the air filter recovery bag Bg outside the connecting duct P _1. Then the water pump is operated, sprayed from the supply port 28 to the connecting duct P ₁ a certain amount of water. Thus, the lower surface 12 and upper surface 18 of the air filter B of the inner surface 4 and the shielding damper 10 of the connection duct P ₁ which is an object to be sprayed surface, wetted with enough water. In addition, it can be confirmed from the outside through the sight glass 6 that the water is sprayed.

  The supplied water is preferably sprayed in a fine mist. This is because it is not desirable that the inner surface can be wetted with the minimum amount of water, and that water is sprayed vigorously, and the water droplets collide with the air filter B and the fine particles adhering to the air from the air filter are scattered again. .

The water sprayed into the connection duct P ₁ adheres to the surface to be sprayed. However, when water exceeding the adherable amount is sprayed, the excess water flows down the inner surface of the connection duct P ₁ and the air filter B And is retained in the air filter collection bag Bg.

By getting wet with water as described above, the fine particles adhering to the upper surface of the air filter are not easily scattered in the air. In this state, through the air filter collection bag Bg, pull the air filter downward, as shown in FIG. 6, removed from the inlet E ₁ connection duct P _1. The air filter collection bag is removed from the opening while the air filter B is placed in the air filter collection bag Bg, and the bag mouth is closed and discarded.

Then, if necessary, to clean the inside of the connecting duct P _1, further attaching the air filter retrieval bag into the opening and returns to the state shown in FIG.

  Hereinafter, other embodiments of the present invention will be described. In these descriptions, the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

FIG. 7 shows a system for exchanging a filter in an exhaust passage, which has a function of preventing scattering of fine particles, according to a second embodiment of the present invention. In this embodiment, the opening in the spray nozzle 28 to the inner surface of the connecting duct P _1. Compared to the first embodiment, since the water supply pipe does not enter the connection duct, dust and fine particles do not adhere to the water supply pipe, and the cleaning work is facilitated. In the illustrated example, the spray nozzles 28 are opened on two opposing surfaces of the peripheral wall 2 of the connection duct, but the arrangement thereof can be changed as appropriate.

P ... Exhaust passage E ₁ ... Suction port (opening) E ₂ ... Air outlet (opening)
P ₁ ... Connection duct 2 ... Peripheral wall 4 ... Inner surface 6 ... Viewing window 8 ... Fixing means
P ₂ ... The remaining exhaust passage part (other than the connecting duct) A ... Shielding means 10 ... Shielding damper 12 ... (underside of shielding shield) 14 ... Rotating shaft 16 ... Rotating motor B ... Air filter 18 ... (of air filter ) Upper surface C ... Liquid supply means 22 ... Water supply tank 24 ... Water supply pump 26 ... Water supply pipe 28 ... Spray nozzle (supply port)
D: Control unit R ₁ ... Work room R ₂ ... Machine room Bg ... Air filter collection bag BL ... Blower fan

Claims (4)

In the filter replacement system for the exhaust passage, where the filter installation location for collecting particulates can be wetted by the supply liquid,
A connection duct formed of a cylindrical portion on the opening side of the exhaust path;
Shielding means capable of tightly blocking the connection duct and the remaining exhaust passage portion with a shielding damper;
An air filter for particulate removal, which is detachably connected to the end of the connection duct;
A liquid supply means including a supply port arranged so as to wet the entire inner surfaces of the connection duct, the shielding damper, and the air filter at or near the connection duct;
A system for exchanging a filter in an exhaust passage, having a function of preventing scattering of fine particles. The connecting duct has a vertical cylindrical shape having a vertical inner peripheral surface with the lower end open,
2. The fine particle according to claim 1, wherein a fixing means capable of fixing an upper end portion of the air filter collection bag is provided in a connecting duct portion above the air filter so as to wrap the air filter from outside. A system for exchanging filters in the exhaust path with a function to prevent scattering.   The said liquid supply means is comprised so that supply of the fixed amount of liquid required in order to wet each whole inner surface of a connection duct, a shielding damper, and an air filter is possible, It is characterized by the above-mentioned. A system for exchanging the filter in the exhaust passage, with a function to prevent the scattering of fine particles. The exhaust passage having the scattering prevention function according to claim 2, wherein the liquid supply means is configured to spray the liquid from the supply port in almost all directions. System for filter replacement.