JP2000296173A - Air cleaning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air cleaning method capable of efficiently trapping suspended contaminants in air and of sufficient purification (washing and sterilizing). SOLUTION: This air cleaning method involves an air circulation path 12 through which contaminated air taken from indoors is cleaned by means of sterilizing water and exhausted indoors as cleaned air, and a water circulation path 14 in which water used in cleaning air is used in cleaning as sterilizing water by imparting bactericidal/sterilization properties thereto. The cleaning of contaminated air by the sterilizing water is effected through a gas-liquid contact by spraying the sterilizing water from a spray nozzle 28 in a direction of crossing an air stream.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air purification method and an air purification device used for the method. In particular, the present invention is suitable for places where a high sanitary environment is required, such as various medical institutions and welfare facilities for the elderly.

[0002]

[Background Art] In hospitals and other medical institutions and nursing homes such as special elderly nursing homes, in-hospital infections caused by bacteria and viruses occur frequently, and airborne bacteria are particularly problematic. Have been.

[0003] In the industrial fields such as food factories, it is necessary to establish a system for preventing germs and fungi, and control of microorganisms in hygiene management is a major issue.

[0004] Furthermore, resistant bacteria which are ineffective even when administered with antibiotics are appearing, and it is an urgent need to respond to airborne contaminants.

[0005] To address these problems, the following clean systems and various sterilizers have been proposed and actually employed.

A cree system using a high-performance filter in an operating room of a hospital, a specific hospital room, or a semiconductor factory.

An electrostatic precipitator / sterilizer for charging and capturing and sterilizing pollutants in a train car, a general living room, and the like.

A deodorizing / sterilizing apparatus for irradiating titanium oxide with ultraviolet light and deodorizing / sterilizing the titanium oxide by oxidizing the titanium oxide for general residential use.

[0009] A sterilizing apparatus using a UV lamp in a food factory or the like and a deodorizing / sterilizing apparatus using ozone gas injection during unmanned operation at night.

[0010]

However, the above-mentioned clean system and various sterilization apparatuses have the following problems (problems).

In the case of the above-mentioned clean system, the cleaning efficiency is high, but the installation work is large and the system is expensive, so that it can be installed only in an extremely limited place.
Moreover, it does not have a sterilizing function.

In the case of the above-mentioned electric dust collecting / sterilizing device,
Together we have limited bactericidal activity, when trying to enlarge the該能force, there is a possibility that the ozone and nitrogen oxides (NO _X) is easy to secondary pollution occurs problems.

In the case of the above deodorizing / sterilizing devices, although a certain degree of deodorizing / sterilizing effect is recognized, the deodorizing / sterilizing efficiency in the air is hardly obtained depending on the type and humidity of pollutants. was there.

[0014] In addition to the above-mentioned problems, in recent air purification, it has been demanded to overcome the following problems.

[0015] Collectively and deodorize dust, pollen, smoke, etc., and capture and sterilize suspended bacteria such as viruses and bacteria, so that they can be performed with high efficiency.

The equipment cost is low and the operation cost is low.

The purifying device is compact in comparison with the processing capacity.

Do not generate pollutants that cause secondary pollution.

In view of the above, an object of the present invention is to provide an air purifying method and an air purifying apparatus capable of efficiently trapping airborne contaminants in the air and sufficiently purifying (cleaning / sterilizing). .

[0020]

SUMMARY OF THE INVENTION An air purifying method and an air purifying apparatus according to the present invention solve the above-mentioned problems by the following constitutions.

An air circulation path for purifying contaminated air taken from the room with sterilizing water and discharging the purified air into the room;
A water circulation path used for the purification as sterilizing water by disinfecting / sterilizing the water used for the air purification.
An air purification method and an air purification apparatus, wherein the purification of the contaminated air with sterilizing water is performed by gas-liquid contact by spraying water in a direction crossing the air flow.

In the above structure, the germ elimination of water is usually performed by one or more of electrolysis sterilization, heat sterilization, ozone sterilization, ultraviolet sterilization, and chemical sterilization.

Among these water disinfection methods and apparatuses, electrolytic disinfection performed by passing water between an anode plate and a cathode plate connected to a DC power supply is desirable because of its high disinfection efficiency.

[0024]

Next, one embodiment of the present invention will be described in detail.

First, an air purification method (air purification device) of the present invention will be described with reference to a block diagram.

The air purification method (air purification device) of the present invention
Has an air circulation path 12 and a water circulation path 14.

The air circulation path 12 purifies contaminated air taken in from the room with sterilizing water and discharges the air as purified air into the room. In the example shown in FIG.
6, a deodorizing section (radical generator) 18, an air purifying section (spray tank) 20, an oxygen converting section (oxidation / reduction catalyst) 22, and an air transporter (fan unit) 24.

Here, the dust removing section 16 is composed of chile, dust, pollen, cigarette smoke, airborne bacteria, and other contaminants.
It has an action of mainly removing dust, that is, collecting dust. Here, the dust removing section 16 may be a bag filter, an electric dust collector, or the like, but is usually formed of a filter material sheet.

The deodorizing section 18 decomposes and deodorizes nitrogen oxides and other odor molecules, and also has a pre-sterilizing action.

Although other deodorizing means may be used as the deodorizing section 18, it is desirable to use a radical generator from the viewpoint of deodorizing efficiency. The deodorization principle of the radical generator is based on the voltage /
Odor molecules are oxidatively decomposed and deodorized by radicals, ozone and the like generated by an electric current (applied voltage: DC 8 to 15 kV).

The purifying section 20 jets water (sterilizing water) having a sterilizing effect on the contaminated air so as to intersect the contaminated air, and makes gas-liquid contact, thereby removing dust (pre-filter) 1.
6 has the effect of simultaneously removing and sterilizing the contaminants not removed in step 6. The purifying section 20 can use the principle of various cleaning and dust collecting devices such as a packed tower, a funnel, a rotary cloaker, an ejector, a rotary sprayer, and a ventilary. 1
0-25) Maruzen, p. 1252) Usually, a spray tank provided with one or more spray nozzles 28 is used. The spray nozzle 28 may be configured to rotate (rotate / revolve).

On the air outlet side of the purifying section 20, multiple filtration layers (filter layers) 25, 26 and 27 are provided. In this filter layer, the first filter layer 25 mainly performs the function of gas-liquid separation, and the two subsequent filter layers 26 and 27 perform the function of final dust removal.

The oxygen conversion section (oxidation / reduction catalyst) 22 converts a small amount of radicals and ozone generated by the deodorization section (radical generator) 18 into oxygen by oxidation / reduction before entering the room, thereby reducing environmental impact. This has the effect of securing the value equal to or less than the reference value.

The air transporter (fan unit) 24 is a power source for air transport of the air circulation path 12, and may be any of a turbo type (axial flow type, centrifugal type) and a positive displacement type, and usually has a water column of 10 mmAq. Use the above blower (fan unit).

The water circulation path 14 is used to remove contaminated water used for purifying the air, to provide sterilization and sterilization water, and to use the purified water again as germicidal water. Water filter 30, disinfection /
It is provided with a sterilizing tank 32 and a water transfer pump 34.

Here, the water filter 30 has the function of primarily removing water stains.

The disinfecting / sterilizing tank 32 is performed by one or more of electrolysis sterilization, heat sterilization, ozone sterilization, ultraviolet sterilization, and chemical sterilization.
Electrolytic sterilization performed by passing water between the anode plate 62 and the cathode plate 64 connected to a DC power supply is desirable because of its good sterilization efficiency / sterilization imparting property.

[0038] The action of the bacteria releasing the electric component / providing bactericidal property is as follows.
Radicals generated by electrolysis, hypochlorous acid, metal ions, or those exerted by battery formation (Japanese Patent Application Laid-Open No. 11-70371 (Japanese Patent Application No. 10-211).
No. 53)).

Naturally, the disinfecting / sterilizing tank 32 has:
Water supply pipe 36 provided with water supply valve 35 and drain valve 3
7 is connected.

The water transfer pump 34 is a turbine type pump.
Regardless of the displacement type, in order to secure stable injection,
A positive displacement magnet pump is desirable.

Next, a specific apparatus to which the above-described air purification method is applied will be described in detail. Note that the same parts as those described above are denoted by the same reference numerals and description thereof may be omitted.

FIG. 2 is an external view applied to a stationary type, and FIG. 3 is a schematic sectional view thereof. In the example of the figure, 67 is an operation panel, 68 is a control box, 69 is a water supply pipe connection port, 7
0 is a drain pipe connection port, 71 is a power cord, and 72 is a water level gauge.

The dust inlet (pre-filter) 16 is provided at the air inlet 40. This pre-filter is the same as that used in air conditioners, etc.
An AFI (Air Filter Instiute test standard) that has a dust removal rate of about 40 to 50%, is made of a material (eg, polyester) that can be washed with a neutral detergent, etc., and has a pressure loss as small as possible. Use

A deodorizing unit (radical generator) 18 as shown in FIGS. The radical generator 18 includes a stainless tube 48 fixed to an insulating plate 44 having a plurality of (four in the illustrated example) air passage holes 42 formed therein, connected to a minus electrode 46, and a plus electrode 50. And a discharge needle 54 provided with a discharge needle 54 held by an insulating weir plate 52 so as to discharge toward the stainless steel tube 48.

On the air outflow side of the deodorizing section 18, the air purifying section 2 is provided.
0 is formed. An air guide louver 56 is disposed on the air inflow side of the air purification unit 20, and a gas-liquid separation filter (gas-liquid separation filter) that separates water and air is provided on the air outflow side.
25, 25 are arranged.

A spray nozzle 28 connected to a water pipe is disposed on the ceiling of the air purification section 20. The spray nozzle 2
The specification 8 is performed by appropriately selecting a spray angle, a spray amount, a spray pattern (cross-sectional shape), a spray flow rate distribution, and a spray particle size. At this time, the method is selected in consideration of how the contact efficiency between the air and the germicidal water is increased, which affects the disinfection efficiency. For example, a conical nozzle is used, and the spray angle is 70 to
80 °, spray amount: 5-7 L / min, spray particle size: 500
μm nozzles are arranged at 100 mm intervals. In the illustrated example, the spray axis of the spray nozzle 28 is orthogonal to the direction of air flow, but it is not necessary to be orthogonal. In other words, if good gas-liquid contact is possible,
Vertical (up / down) or diagonal direction, and further, vortex flow, etc. are arbitrary.

Further, in order to increase the contact efficiency, the shape design of the purifying section (purifying chamber) 20 is also an important factor. For example, it is conceivable that the purification chamber has two stages, or a chamber configuration in which the air flow is a turbulent flow or a spiral flow.

The bottom wall of the air purifying section 20 is formed with a tapered wall 20a so that the spray water is easy to collect, and a water collecting wall 20b is formed on the bottom wall on the air outlet side on the extension surface of the tapered wall 20a. Is formed.

Immediately below the air purification section 20 is a water outlet 20c.
And water filter 30 and disinfecting and sterilizing tank 3
2 are arranged.

The water filter 30 captures dust, dust, pollen, and the like that have been forcibly dropped by the spray water, and primarily removes water stains.

The water filter 30 is provided in the air purifying section 20.
It is desirable to use a screw or a one-touch attachment / detachment method with the bottom wall to simplify maintenance.

As a filter material used for the water filter 30, a carbon filter used for a water purifier or the like or activated carbon is used.

An electrode unit 60 as shown in FIG. 6 is arranged in the sterilizing / sterilizing tank 32 as shown in FIG. In the electrode unit 60, as shown in the drawing, anode plates 62 and cathode plates 64 are alternately arranged on the lower surface of an insulating mounting plate 61. In addition, although the anode / cathode is made into a plate shape from the bacteria removal efficiency, it may be an electrode rod.

Here, the sterilization / sterilizing ability by electrolysis is greatly affected by the material and size of the electrode plates, the interval between the electrode plates, and the amount of electricity. For example, when the flow rate of water is 25 L and the anode plate 62 and the cathode plate 64 of 200 cm ² are arranged two by two at an electrode plate interval of 5 mm and a DC voltage of 24 V is applied as shown in FIG. It became the current value. At this time, the sterilization efficiency was an initial value of 4.2 × 1.
0 ⁵ general bacteria decreased to 1.26 × 10 ³ after 30 min. That is, the sterilization efficiency was 99.7%.

Further, in order to increase the sterilization efficiency, the distance between the electrode plates may be further reduced. As the electrode material, a material obtained by plating iridium on titanium or a ferrite material can be used.

As the gas-liquid separation and filtration layers 25, 25, those similar to those used for the prefilter are used, but those having a small pressure loss are desirable.

A heat exchanger 66 is disposed above the gas-liquid separation and filtration layers 25 for the purpose of, but not necessarily, dehumidification and humidity control. As the heat exchanger 66, an aluminum fin type heat exchanger employed in a commercially available dehumidifier or the like can be used. As the cold heat source, refrigerant,
It is possible to use a compressor or an electronic cooling element.

Above the heat exchanger 66, the oxygen converter 22
Is formed with a redox catalyst. This redox catalyst,
Usually, a honeycomb shape is adopted, and from the viewpoint of catalyst efficiency, it is desirable that the number of cells per inch ² is 400 to 600. However, since the pressure loss increases, the number of cells is 400
The following was adopted, and the contact area was secured by setting the thickness to 20 mm or more.

This catalyst does not completely convert oxygen radicals or ozone into oxygen. The amount of ozone discharged indoors is 0.1 ppm or less according to environmental standards,
Desirably, the content is 0.05 ppm or less.

Above the oxygen conversion section 22, an AFI is further provided in order to reliably prevent dust from entering the room.
A filter unit 29 having a dust removal filter layer (dust filter) 26 having a dust removal rate of 80 to 90% as a standard, and a medium performance or HEPA dust filter layer (dust filter) 27 in the upper stage.
Distribute.

The capacity of the air transporter (fan) 24 disposed in front of the exhaust port is determined by the ventilation cycle of room air. Usually, selection is made assuming a ventilation cycle of 3 to 10 times / min. In this case, considering the pressure loss of the filter, a sirocco fan is desirable (static pressure: 100 mmA).
q). Of course, depending on the ventilation volume, it is of course possible to arrange a plurality of fans.

The stationary type has been described above. However, as shown in FIG. 8, the present invention can also be applied to a spot type only in the dustproof cover 39 of a machine for food processing or the like, or a small partition in a factory. In this case, the air inlet (inlet) 40 and the air outlet (exhaust) 41 are connected by a bellows hose 43 as shown in FIG.

Each connection port of a water supply pipe and a drain pipe can be directly connected to a water pipe or a drain pipe, and a tank or the like can be installed only when necessary to exchange water in the disinfection / sterilization-imparting tank. is there.

[0064]

As described above, the air purification method (air purification device) of the present invention provides an air circulation path for purifying contaminated air taken in from a room with sterilizing water and discharging the purified air into the room as described above. A water circulation path for disinfecting / sterilizing water used for air purification and using it for purification as sterilizing water, and sterilizing contaminated air with sterilizing water in a direction crossing the air flow. With a configuration in which gas-liquid contact is performed by spraying water, the suspended contaminants in the air can be efficiently captured and sufficiently purified (washed / sterilized).

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an air purification method of the present invention.

FIG. 2 is a perspective view of an air purification device when the air purification method is applied to a stationary type.

FIG. 3 is a schematic vertical sectional view of FIG. 2;

FIG. 4 is a side view of a radical generator used in a deodorizing section of the air purification device of FIG.

FIG. 5 is a perspective view of the same.

FIG. 6 is a perspective view of an electrolysis unit arranged in a sterilization / sterilization-imparting tank of the air purification device of FIG.

FIG. 7 is a plan view of a tank for imparting sterilization / sterilization properties of the air purification device of FIG. 2;

FIG. 8 is a perspective view when the air purification method of the present invention is applied to a spot type.

[Explanation of symbols]

 Reference Signs List 12 air circulation path 14 water circulation path 16 dust removal section (pre-filter) 18 deodorization section (radical generator) 20 air purification section (spray tank) 22 oxygen conversion section (oxidation / reduction catalyst) 24 air transporter (fan unit) 28 spray Nozzle 30 Water filter 32 Disinfecting / sterilizing tank 34 Water transfer pump 62 Electrolytic sterilizing anode plate 64 Electrolytic sterilizing cathode plate

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C02F 1/50 531 C02F 1/50 531R 560 560F 560A 560C 1/78 1/78 F term (Reference) 4C080 AA07 AA10 BB02 BB05 CC07 HH03 KK08 LL02 MM08 QQ12 QQ17 4D037 AA02 AA15 AB03 BA18 CA02 CA04 CA12 CA16 4D050 AA04 AA08 AB06 BB02 BD06 CA01 CA07 CA10 CA12 CA15 4D061 DA10 DB01 EA02 EB20 EB30 GC31

Claims (6)

[Claims] 1. An air circulation route for purifying contaminated air taken in from a room with sterilizing water and discharging the purified air into the room as a purified air, and disinfecting / sterilizing the water used for purifying the air to obtain sterilizing water. And a water circulation path used for the purification, wherein the purification of the contaminated air with the sterilizing water is performed by gas-liquid contact by spraying the sterilizing water in a direction crossing the air flow. Purification method. 2. The method according to claim 1, wherein the water is sterilized by one or more of electrolytic sterilization, heat sterilization, ozone sterilization, ultraviolet sterilization, and chemical sterilization. The air purification method as described. 3. The air purification method according to claim 2, wherein the disinfection of water is electrolytic sterilization performed by passing water through an anode plate and a cathode plate connected to a DC power supply. 4. An air circulation path for purifying contaminated air taken in from a room with sterilizing water and discharging the air as purified air into the room, and disinfecting / sterilizing the water used for purifying the air to obtain sterilizing water. And a water circulation path used for the purification, wherein the sterilizing water purification unit in the air circulation path includes one or more spray nozzles for spraying water in a direction crossing the air flow. An air purification device, characterized in that: 5. The disinfecting / sterilizing tank in the water circulation path is capable of performing one or more of electrolysis sterilization, heat sterilization, ozone sterilization, ultraviolet sterilization, and chemical sterilization. The air purification device according to claim 4, wherein: 6. The air purifying apparatus according to claim 5, wherein at least one pair of an anode plate and a cathode plate connected to a DC power supply is arranged in the disinfecting / sterilizing tank.