JPH11347331A - Air washer - Google Patents

Abstract

[57] [Abstract] [Problem] To reliably remove dust and harmful gas from the air and reduce the supply of pure water used as clean water.
Provided is an air washer that performs humidification with high saturation efficiency. SOLUTION: An upstream air washer unit 13 and a downstream air washer unit 14 are provided in communication with each other along a flow direction of an air flow,
Each of the air washers 13 and 14 has a water spray chamber 15, 16
And washer media 17, 18, 22, 23, 24
And nozzles 19 and 25 for spraying spray water reaching washer media 18 and 23, and water tank 1 for receiving spray water.
5 and 27, circulating water supply systems 21 and 28 for supplying circulating water to the nozzles 19 and 25, and a make-up water supply system 36 for supplying make-up water to the nozzles 26 are provided.
And an overflow pipe 39 was provided in the water storage tank 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner in a semiconductor factory or the like, and more particularly to an air washer that removes dust and harmful gas from the air and performs humidification with high saturation efficiency.

[0002]

2. Description of the Related Art A conventional air washer is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-96122, and its outline is shown in FIG. In FIG. 4, the air washer 1
A water spray chamber 2 through which air passes from the upstream side to the downstream side is provided, and a partition plate 3 extending substantially in the center of the water spray chamber 2 in the air flow direction (indicated by an arrow in the drawing) is provided. The nozzle 4a of the water spraying device 4 is disposed so as to face.

In this air washer 1, when clean water is sprayed as spray water from a nozzle 4a of a water spray device 4 so as to collide with the partition plate 3, dust in the air passing through the water spray chamber 2 is sprayed onto the spray water. The dust collides with the spray water to reach the partition plate 3 and is supplemented by a water film formed on the surface of the partition plate 3, and flows down along the partition plate 3 as the water film falls.

[0004]

The above-mentioned air washer 1 is intended to remove dust from the air. To humidify the air to near saturation with the air washer 1, use a water spray chamber 2. It is necessary to set the ratio of the amount of spray water to the flow rate of air at a higher ratio than the normal ratio for removing dust, and a pump having a large output for pumping clean water to the nozzle 4a of the water spray device 4 is required. In other words, it was not possible to efficiently humidify the air.

When the harmful gas components in the air passing through the water spray chamber 2 are to be absorbed and removed by the spray water, the cleanliness of the spray water is set to a predetermined value in order to maintain the harmful gas removal performance. It is necessary to keep the above, and when circulating the spray water, it is necessary to supply fresh clean water so that the concentration of the harmful gas component taken into the spray water is kept below a predetermined value.

However, when supplying clean water to the circulating water circulating in the system, if the clean water is supplied to a water tank for temporarily storing the circulating water, the harmfulness of the circulating water staying in the water tank is reduced. Since the concentration of the gas component was diluted, in other words, the clean water supplied as make-up water was polluted by the harmful gas components in the water tank, so the cleanliness of the replenished clean water could not be fully utilized. . In addition, when pure water is used for the entire amount of make-up water, a large amount of pure water is required, and a large-capacity pure water production apparatus is required, resulting in an increase in cost.

[0007] Further, in a semiconductor factory where the gas removal rate is limited and the degree of integration is dramatically increased, further reduction of harmful gas is required, and a high-cost chemical filter is installed downstream of the air washer. Needed.

Alternatively, depending on the location of a semiconductor factory, there are areas where high concentrations of harmful gases are generated, and the gas concentration that has passed through a conventional air washer becomes only equal to the gas concentration of general outside air. It was necessary to install an expensive chemical filter downstream of the air washer.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and reliably removes dust and harmful gas from the air, reduces the supply of pure water used as clean water, and provides a humidifier having a high saturation efficiency. The purpose of the present invention is to provide an air washer for performing the following.

[0010]

In order to solve the above-mentioned problems, an air washer according to the present invention is provided so that an upstream air washer portion and a downstream air washer portion are communicated with each other along a flow direction of an air flow. A first water spray chamber having an air inlet and an air outlet in the washer portion, wherein an air flow is generated from the air inlet toward the air outlet; a first washer media disposed at the air inlet of the first water spray chamber; A second washer media disposed at an air outlet of the first water spray chamber, and a spray located downstream of the first washer media in the first water spray chamber and reaching the first washer media in a direction opposite to the air flow. A first stage nozzle for spraying water, a first water storage tank located in the water spray chamber for receiving the downwardly flowing spray water, and a first circulating water for circulating the circulating water in the first water storage tank to the first stage nozzle Supply system and downstream air A second water spray chamber having an air inlet and an air outlet in the shear portion, wherein an air flow is generated from the air inlet toward the air outlet; a third washer medium disposed at the air inlet of the second water spray chamber; A fourth washer media located across the airflow within the second water spray chamber, a fifth washer media located at the air outlet of the second water spray chamber, and downstream from the third washer media within the second water spray chamber. A second stage nozzle for spraying spray water reaching the third washer media in a direction opposite to the air flow, and a second stage nozzle located downstream of the fourth washer media in the second water spray chamber, and A third stage nozzle for spraying the spray water in the direction or the opposite direction, a second water storage tank located in the second water spray chamber for receiving the spray water flowing down, and a second water storage tank for circulating water in the second water storage tank. A second circulating water supply system that circulates and supplies the stage nozzle A makeup water supply system for supplying makeup water to the third stage nozzle is provided, a communication pipe communicating the first water storage tank and the second water storage tank is provided, and an overflow pipe is provided in the first water storage tank. is there.

[0011] With the above structure, in the upstream air washer section, water from the first water storage tank is supplied to the air flow flowing from the air inlet of the first water spray chamber through the first washer medium so as to oppose the flow. When sprayed from the first-stage nozzle, the spray water collides with dust and harmful gas in the air, and the colliding dust and harmful gas in the air reach the first washer media together with the spray water, and the first washer media becomes dusty and harmful. Capture spray water with gas.

The spray water that has reached the first washer media is:
The dust attached to the first washer medium is washed away and flows down, while taking in the harmful gas, flowing into the first water storage tank, and evaporating in the process of flowing down to humidify the air.

A part of the spray water that has not collided with the first washer medium collides with the ceiling surface, the wall surface or the water storage surface of the water spray chamber, but otherwise moves by an air flow and evaporates in the process. In addition to humidifying the air, dust and harmful gas in the air are taken in and reach the second washer media, and the second washer media captures spray water accompanied by dust and harmful gas. The circulating water staying in the first water storage tank is
Circulate through the circulating water supply system and spray again from the first stage nozzle. The air that has passed through the second washer media flows into the downstream air washer through the air outlet.

[0014] In the downstream air washer section, with respect to the air flow flowing through the third washer media from the air inlet of the second water spray chamber, water from the second water storage tank is supplied from the third nozzle so as to oppose the flow. When spraying, the spray water collides with dust and harmful gas in the air, and the colliding dust and harmful gas in the air reaches the third washer media together with the spray water, and the third washer media sprays with dust and harmful gas. Capture water.

The spray water that has reached the third washer media is:
The dust attached to the third washer medium is washed off and flows down, while taking in the harmful gas, flowing into the second water tank, and evaporating in the course of flowing down to humidify the air.
In this process, the humidification amount is very small, being almost saturated. After this, no humidification takes place.

A part of the spray water that has not collided with the third washer media collides with the ceiling surface, wall surface or water storage surface of the second water spray chamber, but otherwise moves on the air flow, and the process proceeds. In the above, dust or harmful gas in the air is taken in and reaches the fourth washer media, and the fourth washer media captures spray water with dust or harmful gas.

The spray water that has reached the fourth washer media is:
The dust attached to the fourth washer medium is washed away and flows down, while taking in the harmful gas and flowing into the second water storage tank. The circulating water staying in the second water tank circulates through the second circulating water supply system, and is sprayed again from the second stage nozzle.

When clean make-up water is sprayed from the third nozzle to the air flow that has passed through the fourth washer media, the spray water of clean water collides with dust and harmful gas remaining in the air and collides. The dust and the harmful gas reach the fifth washer media together with the spray water, and the fifth washer media captures the spray water with the dust and the harmful gas.

The spray water that has reached the fifth washer media is:
The dust attached to the fifth washer medium is washed away and flows down, while taking in the harmful gas and flowing into the second water storage tank. The clean water that has flowed into the second water storage tank joins the circulating water as makeup water, and is sprayed as circulating water from the second stage nozzle through the second circulating water supply system. The air that has passed through the fifth washer media flows out of the air outlet as clean air that is purified and sufficiently humidified.

The make-up water compensates for the amount of circulating water that decreases with humidification of the air, and the amount necessary to maintain the concentration of harmful gas in the circulating water at a certain value or less is determined by the third-stage nozzle and the second-stage nozzle. The water is supplied to the water storage tank, and excess water is discharged from an overflow pipe provided at a position where the water levels of the first water storage tank and the second water storage tank are maintained.

As described above, since the spray water is injected from the first-stage nozzle and the second-stage nozzle so as to face the air flow, and the air is humidified so as to be turned back, the ratio of the amount of the spray water to the flow rate of the air is reduced. Even if it is set low, the dust and harmful gas in the air can be sufficiently removed by the respective washer media and the air can be humidified efficiently, and the output of the actuator such as a pump in each circulating water supply system can be reduced.

Further, the clean water sprayed from the third stage nozzle becomes spray water while maintaining the initial cleanliness, so that the harmful gas passing through the first, second, third, and fourth washer media is removed. On the other hand, high removal performance can be exhibited by effectively utilizing the cleanliness.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 3, the air washer 11 is provided with a main body casing 1 having a rectangular channel cross section.
2, an upstream air washer section 13 and a downstream air washer section 14 are provided in communication with each other along the flow direction of the air flow, and the upstream air washer section 13 is provided with a first water spray chamber 15 having a predetermined length. And the downstream air washer section 14 has a second water spray chamber 16 of a predetermined length.

The first water spray chamber 15 is connected to a duct (not shown) at an air inlet 15a formed at one end thereof.
5 flows out from the air outlet 15b formed at the other end through the flow path 5.

In the first water spray chamber 15, a first washer media 17 is disposed at an air inlet 15a, and a second washer media 18 is disposed at an air outlet 15b. A plurality of first communicating with the circulating water supply system;
The step nozzle 19 is located downstream of the first washer media 17. The first stage nozzle 19 sprays spray water reaching the first washer media 17 in a direction opposite to the air flow. As for the pressure of the spray water from the first-stage nozzle 19 and the distance between the first-stage nozzle 19 and the first washer media 17, a predetermined spray angle (about 60 to 70 degrees) is ensured. It is set so that a part (about ３) of the spray water collides with the first washer media 17 when a predetermined flow rate of air is flowing through the inside. Also,
Part of the remaining water (about 1/3, 2/9 of the total water amount) collides with the ceiling surface, wall surface, etc. in the first water spray chamber 15, and the remaining water (5/9 of the total water amount). Is set to move along the flow of air and collide with the second washer media 18.

At the lower part of the first water spray chamber 15, there is provided a first water storage tank 20 for receiving the spray water flowing down, and the circulating water staying in the first water storage tank 20 is circulated and supplied to the first stage nozzle 19. A circulating water supply system 21 is provided in communication with a lower part of the first water storage tank 20.

The second water spray chamber 1 of the downstream air washer section 14
6 is connected to an air outlet 15b of the upstream air washer portion 14 at an air inlet 16a formed at one end thereof,
The inflowing air A flows out of the air outlet 16b formed at the other end through the flow path of the second water spray chamber 16.

In the second water spray chamber 16, a third washer medium 22 is disposed at the air inlet 16a, a fourth washer medium 23 is disposed across the air flow, and a fourth washer medium 23 is disposed at the air outlet 16b. 5 washer media 24 are arranged. The third washer media 2 is located downstream of the third washer media 22 in a direction opposite to the air flow.
A second stage nozzle 25 for spraying the spray water reaching the second position is disposed, and is located downstream from the fourth washer media 23,
A third-stage nozzle 26 for spraying the spray water in the forward direction of the air flow is arranged.

The pressure of the spray water from the second stage nozzle 25;
As for the distance between the second stage nozzle 25 and the third washer media 22, a predetermined spray angle (60 to 70 degrees) is secured, and the spray is performed when a predetermined flow rate of air is flowing into the second water spray chamber 16. It is set to such an extent that a part (about 1/3) of the water collides with the third washer medium 22. In addition, a part of the remaining water (about 1/3, 2/9 of the total water amount) collides with the ceiling surface, the wall surface, and the like in the second water spray chamber 16, and the remaining water (5/5 of the total water amount). 9) moves in the air flow,
The setting is made so as to collide with the washer media 23.

The pressure, the installation position and the spray direction of the spray water of the third stage nozzle 26 are such that when a predetermined amount of air is flowing into the second water spray chamber 16, the spray water is supplied to the upstream fourth washer medium 23. 5th washer media 24 without colliding with
Set to spread widely and collide. 3rd shown
The spray direction of the step nozzle 26 is the forward direction of the air flow, but may be the reverse direction of the air flow as long as the above conditions are satisfied.

At the lower part of the second water spray chamber 16, there is provided a second water tank 27 for receiving the spray water flowing down, and the circulating water staying in the second water tank 27 is circulated and supplied to the second stage nozzle 25. A second circulating water supply system 28 is provided in communication with a lower part of the second water tank 27.

Each of the first circulating water supply system 19 and the second circulating water supply system 28 has a suction pipe 31 opening below each of the water storage tanks 20 and 27, a circulation pump 32 connected to the suction pipe 31, A motor 33 for driving the circulating pump 32 and each of the water spray chambers 15 and 16 connected to a discharge port of the circulating pump 32;
And a plurality of branch pipes 35 branching from the discharge pipe 34 and vertically disposed inside the water spray chambers 15 and 16. The first stage nozzle 19 and the second stage nozzle 25 are provided.

A makeup water supply system 36 for supplying pure water as makeup water to the third stage nozzle 26 is connected to a clean water supply device (not shown) or a pure water supply device (not shown). It has a water supply pipe 37 disposed above the two-water spray chamber 16, and the water supply pipe 37 is provided with a plurality of third-stage nozzles 26. A communication pipe 38 is provided to communicate the first water storage tank 20 and the second water storage tank 27, and the overflow pipe 3 is connected to the first water storage tank 20.
9 is provided, and a preliminary water supply pipe 40 is provided in the second water storage tank 27.

An eliminator 41 for removing water droplets and the like contained in the air passing through the second water spray chamber 16 is disposed downstream of the second water spray chamber 16. A cooling chamber 42 of a predetermined length having a channel cross-sectional shape similar to that of the second water spray chamber 16 is connected to 16b. A cooling coil 43 is provided as a cooler inside the cooling chamber 42, and a drain pan 44 is formed below the cooling chamber 42. A drain pipe 45 communicating with the outside of the cooling chamber 42 is connected to the recess of the drain pan 44. A blower (not shown) is arranged on the downstream side of the second water spray chamber 16, and by operating the blower, air is guided to the flow path of each water spray chamber.

Each of the washer media has a shape substantially equal to the cross section of the flow path of the air flow, and is made of polyvinyl chloride fiber or stainless steel wire.
It is a mat having a thickness of about 50 mm.

The operation of the above configuration will be described. The air A flows into the first water spray chamber 15 through the first washer media 17 from the air inlet 15a. The circulating water from the first water storage tank 20 is sprayed from the first-stage nozzle 19 so as to face this air flow. The spray water collides with dust or harmful gas in the air, and the colliding dust or harmful gas in the air reaches the first washer media 17 together with the spray water, and the first washer media 17 is sprayed with dust or harmful gas. To capture. In the first washer media 17,
The spray water rinses away dust adhering to the first washer media 17 and flows down.
It flows into the water storage tank 20. The spray water evaporates in the process of flowing down to humidify the air.

The spray water that has not collided with the first washer media 17 partially collides with the ceiling surface, wall surface, or water storage surface of the first water spray chamber 15, but otherwise moves on the air flow, In the process, while evaporating and humidifying the air, dust and harmful gas in the air are taken in and reached the second washer media 18, and the second washer media 18 captures the spray water with the dust and harmful gas.

In the second washer media 18, the spray water rinses off the dust attached to the second washer media 18 and flows down.
Flow into zero. The spray water evaporates in the process of flowing down to humidify the air. The water flowing into the first water storage tank 20 is
The water is sprayed as circulating water from the first stage nozzle 19 through the circulating water supply system 21.

In the downstream air washer section 14, the water from the second water storage tank 27 is supplied to the air flow flowing from the air inlet 16a of the second water spray chamber 16 through the third washer medium 22 so as to face the flow. When sprayed from the third stage nozzle 26, the spray water collides with dust and harmful gas in the air, and the colliding dust and harmful gas in the air reach the third washer media 22 together with the spray water, and the third washer media 22 Captures spray water with dust and harmful gases.

The spray water that has reached the third washer media 22 rinses away dust adhering to the third washer media 22, flows down, takes in harmful gases, flows into the second water storage tank 27, and a little in the process of flowing down. But it evaporates and humidifies the air.

A part of the spray water that has not collided with the third washer media 22 collides with the ceiling surface, the wall surface or the water storage surface of the second water spray chamber 16, but otherwise moves on the air flow. In the process, dust or harmful gas in the air is taken in and reaches the fourth washer media 23, and the fourth washer media 23 captures spray water accompanied by dust or harmful gas.

The spray water that has reached the fourth washer medium 23 rinses away dust adhering to the fourth washer medium 23, flows down, takes in harmful gases, and flows into the second water storage tank 27. The circulating water staying in the second water tank 27 is
Circulated through the second circulating water supply system 28 and sprayed again from the second stage nozzle 25.

When clean make-up water is sprayed from the third stage nozzle 26 to the air flow passing through the fourth washer medium 23, the spray water of clean water collides with dust and harmful gas remaining in the air, The colliding dust and harmful gas reach the fifth washer media 24 together with the spray water, and the fifth washer media 24 captures the spray water with the dust and harmful gas.
The spray water that has reached the fifth washer medium 24 rinses away dust adhering to the fifth washer medium 24, flows down, takes in harmful gases, and flows into the second water storage tank 27.

The clean water flowing into the second water storage tank 27 joins the circulating water as make-up water, and is sprayed as circulating water from the second stage nozzle 25 through the second circulating water supply system 28. The air that has passed through the fifth washer media 24 flows out of the air outlet 16b as clean air that has been purified and sufficiently humidified.

The make-up water supplements the amount of circulating water that decreases with the humidification of the air, and the amount necessary to maintain the concentration of harmful gas in the circulating water at a certain value or less. 2 to the first water storage tank 27 and the second water storage tank 27
The overflow pipe 39 is used to maintain the water level in the water storage tank 27.
Drain excess water from

The air that has passed through the fifth washer medium 24 flows into the eliminator 41, where water drops in the air are removed. The air flowing out of the eliminator 41 is guided to a cooling chamber 42 and is cooled by a cooling coil 43.

Therefore, in the above-described configuration, the inflowing air can be purified in multiple stages, and since highly clean water is sprayed downstream of the air flow, the gas removing effect is enhanced.
It can also be used in areas where the concentration of harmful gases in the atmosphere is high.

Incidentally, Table 1 shows the effect of the present invention. As is clear from the table, even when the present invention is applied to the atmosphere having a general gas concentration, it is applied to the atmosphere having a high gas concentration. Even in such a case, an excellent purification effect can be obtained.

[0049]

[Table 1]

[0050]

As described above, according to the present invention, the spray water is injected from the first stage nozzle and the second stage nozzle so as to oppose the air flow, and the air is humidified so as to be turned back. Even if the ratio of the amount of spray water to the flow rate of water is set low, dust and harmful gas in the air can be sufficiently removed and air can be humidified efficiently by each washer media, and actuators such as pumps in each circulating water supply system Can be reduced.

Further, since the clean water sprayed from the third stage nozzle becomes spray water while maintaining the initial cleanliness, the harmful gas passing through the first, second, third and fourth washer media is removed. On the other hand, high removal performance can be exhibited by effectively utilizing the cleanliness.

[Brief description of the drawings]

FIG. 1 is a plan sectional view of an air washer showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view of the air washer.

FIG. 3 is a cross-sectional view of the air washer.

FIG. 4 is a schematic view showing a configuration of a conventional air washer.

[Explanation of symbols]

 A Air 11 Air washer 12 Body casing 13 Upstream air washer section 14 Downstream air washer section 15 First water spray chamber 15a Air inlet 15b Air outlet 16 Second water spray chamber 16a Air inlet 16b Air outlet 17 First washer media 18 Second Washer media 19 1st stage nozzle 20 1st water storage tank 21 1st circulating water supply system 22 3rd washer media 23 4th washer media 24 5th washer media 25 2nd stage nozzle 26 3rd stage nozzle 27 2nd water reservoir 28 Second circulating water supply system 38 Connecting pipe 39 Overflow pipe

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shuzo Akita 28 Hirade Industrial Park, Utsunomiya City, Tochigi Prefecture Inside Kubota Air Quality Co., Ltd. (72) Inventor Masaaki Shinohara 28, Hirade Industrial Park, Utsunomiya City, Tochigi Prefecture Inside Kubota Air Conditioning Tochigi Plant

Claims (1)

[Claims] An upstream air washer portion and a downstream air washer portion are provided in communication with each other along a flow direction of an air flow, and the upstream air washer portion has an air inlet and an air outlet,
A first water spray chamber in which an air flow is generated from an air inlet to an air outlet, a first washer media disposed at an air inlet of the first water spray chamber, and a second washer disposed at an air outlet of the first water spray chamber A first medium for spraying spray water, which is located downstream of the first washer medium in the first water spray chamber and reaches the first washer medium in a direction opposite to the air flow;
A stage nozzle, a first water storage tank positioned in the water spray chamber to receive the spray water flowing down, and a first circulating water supply system for circulating the circulating water in the first water storage tank to the first stage nozzle, The downstream air washer has an air inlet and an air outlet,
A second water spray chamber in which an air flow is generated from the air inlet to the air outlet, a third washer media disposed at the air inlet of the second water spray chamber, and a second washer medium disposed across the air flow in the second water spray chamber. A fourth washer media, a fifth washer media disposed at an air outlet of the second water spray chamber, and a third washer media located downstream of the third washer media in the second water spray chamber, the third being directed in a direction opposite to the air flow. A second stage nozzle for spraying the spray water reaching the washer media, and a third nozzle for spraying the spray water in the forward or reverse direction of the air flow, which is located downstream of the fourth washer media in the second water spray chamber. A stage nozzle and a second
The second to receive the spray water flowing down located in the water spray chamber
A water storage tank, a second circulating water supply system for supplying circulating water in the second water storage tank to the second stage nozzle, and a makeup water supply system for supplying makeup water to the third stage nozzle. An air washer comprising: a connecting pipe communicating between a tank and a second water storage tank; and an overflow pipe provided in the first water storage tank.