JP6607712B2 - Air purification device - Google Patents

Description

  The present invention relates to an air purification device.

  2. Description of the Related Art Conventionally, air purifiers that remove fine particles or gaseous substances contained in air by bringing cleaning water into contact with air have been used.

  As such a gas-liquid contact type air purifier, scrubbers that are often used in air conditioners and external air conditioners of buildings are known, and in particular, fillers such as Raschig rings and terralet packing are used. A packed tower type is known. A packed tower type scrubber is suitable for industrial use, but because the height of the packed bed is increased and the equipment is enlarged, it is introduced into the living space for home use, that is, in a house such as a detached house or an apartment house. It is not preferable as an application for purifying the outside air or the air circulating in the living space.

  On the other hand, in the air-liquid contact type air purifying apparatus, it has been proposed to fill the gas-liquid contact chamber with various fillers, and it is expected that the apparatus will be downsized. As such a filler, for example, it has been proposed to use a honeycomb structure (see Patent Document 1) or a fiber assembly (see Patent Document 2).

JP 2007-143936 A JP 2013-233497 A

  By the way, the filler in the gas-liquid contact chamber is required to exhibit a high removal performance with respect to fine particles, gaseous substances and the like while suppressing an increase in pressure loss.

  However, the filler having the honeycomb structure described in Patent Document 1 is effective for reducing the pressure loss, but is mainly used for the purpose of removing viruses in the air. The removal performance of the particulate matter is not high. Moreover, although the fiber assembly described in Patent Document 2 is configured to achieve both a low pressure loss and a high removal performance of fine particles, gaseous substances, and the like, the particle diameter is still small (for example, 1 μm or less). ) The removal performance of fine particles is not enough.

  Accordingly, an object of the present invention is to provide an air purification device that removes particulates and gaseous substances contained in air with high efficiency while suppressing an increase in pressure loss.

In order to achieve the above-described object, an air purification device of the present invention is provided between an intake port and an exhaust port provided in a housing and between the intake port and the exhaust port, and is introduced into the housing from the intake port. The gas-liquid contact portion where the air comes into contact with the cleaning water and the water sprinkling means which is provided above the gas-liquid contact portion and sprays the cleaning water onto the gas-liquid contact portion. Gas-liquid contact portion, the fineness has a filling section monofilaments or multifilament fiber維集combined processed into flocculent is filled in 0.5 to 100 denier, fiber aggregate filled in the filling portion , 900 to 5000 m ² / m ³ , and a bulk density of 10 kg / m ³ or more and 45 kg / m ³ or less.

  In such an air purification device, the long fiber aggregate in the gas-liquid contact portion achieves an appropriate water retention state, while the opportunity for contact between the air to be treated and the cleaning water increases dramatically. While suppressing an increase in loss, it is possible to exert high removal performance on fine particles, gaseous substances, and the like, particularly on fine particles having a small particle diameter.

  As described above, according to the present invention, it is possible to provide an air purification apparatus that removes particulates and gaseous substances contained in air with high efficiency while suppressing an increase in pressure loss.

It is the schematic which shows the structure of the air purification apparatus by one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the gas-liquid contact part of the air purification apparatus of this embodiment. It is a photograph which shows an example of the long-fiber assembly of this embodiment.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic diagram showing a configuration of an air purification device according to an embodiment of the present invention.

  The air purification device 1 is provided between the air inlet 3 provided on the lower side surface of the housing 2, the air outlet 4 provided on the upper side surface of the housing 2, and the air inlet 3 and the air outlet 4. A gas-liquid contact part 5, a watering nozzle (watering means) 6 for spraying cleaning water to the gas-liquid contact part 5, a circulation tank (washing water storage means) 7 for storing the washing water, and washing water in the circulation tank 7 Is supplied to the watering nozzle 6 to have a circulation pump (washing water circulation means) 8 for circulating the washing water. With such a configuration, the air purification device 1 causes the air-liquid contact portion 5 to bring the air introduced from the air inlet 3 into the housing 2 and the cleaning water sprayed from the water spray nozzle 6 into contact with each other. Is supposed to be washed.

  The gas-liquid contact part 5 is comprised from the fiber assembly which has a specific structure. Thereby, the air purification apparatus 1 of this embodiment removes fine particles and gaseous substances contained in the air, particularly fine particles having a small particle diameter (for example, 1 μm or less) with high efficiency while suppressing an increase in pressure loss. It becomes possible. The detailed configuration of the gas-liquid contact portion 5, particularly the fiber assembly will be described later.

  The watering nozzle 6 is provided above the gas-liquid contact portion 5. The watering nozzle 6 is capable of spraying water having a mist and a small particle size, and therefore, a spray type that can efficiently wet the gas-liquid contact portion 5, particularly a fan-shaped spray nozzle or an annular spray nozzle is suitable. is there. The fan-type spray nozzle has a small amount of spray water, can disperse the spray water, and can spray water over a wide range. The annular spray nozzle is not easily clogged, and can spray water over a wide range by turbulently dispersing the sprayed water in the rising airflow of the air to be treated. In addition, spray water from the annular spray nozzle collides with spray water from adjacent nozzles or intersecting spray water, resulting in water droplets becoming coarse and / or finer. become. The coarse water droplets fall to wet the gas-liquid contact portion 5 and wash away the fine particles and gaseous substances that have been taken in. The fine water droplets float and repeat micronization and coarsening. Become. It is preferable that a plurality of fan spray nozzles and annular spray nozzles are arranged so that the spray water intersects or is parallel.

  The circulation tank 7 is provided in the lower part of the housing 2 below the gas-liquid contact part 5. An external water source 10 is connected to the circulation tank 7 via a pipe 9, and it is possible to replenish and replace cleaning water from the external water source 10 by controlling a water supply valve 11 provided in the pipe 9. A drain valve 12 for draining water is provided on the bottom surface of the circulation tank 7.

  The circulation pump 8 has a primary side (suction side) connected to the circulation tank 7 via a pipe 13, and a secondary side (discharge side) connected to the watering nozzle 6 via a pipe 14. Water can be circulated. In the present embodiment, the circulation pump is provided outside the housing 2, but may be provided inside the housing 2 as long as the cleaning water is circulated. Further, the circulation pump 8 may be a submersible pump provided in the circulation tank 7.

  Note that the cleaning water used for purifying the air is not particularly limited as long as it is clean water, and tap water, well water, distilled water, pure water, electrolytic water, and the like can be used. Further, the circulation tank 7 and the circulation pump 8 are not necessarily provided. Therefore, the cleaning water that has come into contact with the air at the gas-liquid contact portion 5 may be drained as it is, and the cleaning water is circulated. It does not have to be.

  Furthermore, the air purification device 1 has an eliminator (drip-proof plate) 15 provided above the watering nozzle 6 and a blower 16 provided above the eliminator 15 and before the exhaust port 4. . The eliminator (drip-proof plate) 15 has a function of preventing spray water from scattering from the water spray nozzle 6. The blower 16 is provided in order to introduce external air from the intake port 3 and exhaust the air that has passed through the gas-liquid contact portion 5 from the exhaust port 4. The blower 16 only needs to be configured such that the air introduced from the intake port 3 is discharged from the exhaust port 4, and is provided on the suction port 3 side to push external air into the housing. May be. The blower 16 may be provided outside the housing 2. Further, a humidity adjusting means such as a desiccant rotor may be provided above the eliminator 15 in order to remove a large amount of moisture contained in the air purified by the gas-liquid contact method.

  Next, an air purification operation using the air purification device 1 of the present embodiment will be briefly described.

  The washing water stored in the circulation tank 7 is supplied to the watering nozzle 6 by the circulation pump 8. The washing water supplied to the watering nozzle 6 is sprayed to the gas-liquid contact part 5 by the watering nozzle 6 and retained by the fiber assembly of the gas-liquid contact part 5. On the other hand, when the blower 16 is activated, the inside of the housing 2 is in a reduced pressure state, and the air to be purified is introduced from the air inlet 3 into the housing 2. The introduced air flows through the inside of the housing 2 from the bottom to the top by the blower 16 and reaches the gas-liquid contact portion 5. The air that has reached the gas-liquid contact portion 5 makes gas-liquid contact with the fiber assembly of the gas-liquid contact portion 5, and particulate matter and gaseous chemical substances in the air are removed by the wash water. The purified air is discharged from the exhaust port 4 by the blower 16.

  Next, the structure of the gas-liquid contact part of this embodiment is demonstrated. FIG. 2 is a schematic cross-sectional view showing the configuration of the gas-liquid contact portion.

  The gas-liquid contact part 5 of this embodiment has a fiber assembly layer having a three-layer structure composed of different types of fiber assemblies. Specifically, the gas-liquid contact portion 5 includes an intermediate layer 21 made of long fiber aggregates, and an upper layer 22 and a lower layer 23 that are arranged vertically so as to sandwich the intermediate layer 21 and are both made of short fiber aggregates. doing. The intermediate layer 21 constitutes a filling portion in which a long fiber assembly is filled between the upper layer 22 and the lower layer 23. In this embodiment, a long fiber assembly is filled in a mold (not shown) sandwiched between the upper layer 22 and the lower layer 23 and opened at the top and bottom, but the upper layer is simply used without using a container such as a mold. The long fiber aggregate may be filled in the space formed by the lower layer 22 and the lower layer 23. Although not shown, the gas-liquid contact portion 5 is a holding member for holding the fiber assembly layer, such as a block-like fiber assembly, a wire mesh, or a punching plate, below or above the fiber assembly layer. May be installed.

  The long fiber aggregate constituting the intermediate layer 21 has a three-dimensional shape that is elastic as a whole because a number of fine voids are formed inside by irregularly intertwining the crimped long fibers. It is configured. That is, the long fiber aggregate constituting the intermediate layer 21 is formed by gathering the crimped long fibers into a cotton shape. Fig.3 (a) is a photograph which shows an example of the long-fiber assembly of this embodiment, FIG.3 (b) is an electron which expands the long-fiber assembly shown to Fig.3 (a) 100 times. It is a micrograph. As described above, the long fiber aggregate of the present embodiment is longer than the short fiber aggregate of, for example, absorbent cotton, so that the fibers constituting the long fiber aggregate are generated and discharged together with the purified air. There is no tangling.

With such a configuration, the long fiber aggregate constituting the intermediate layer 21 can ensure a very large specific surface area (fiber surface area per unit volume), for example, 900 to 5000 m ² / m ³ . As a result, the opportunity for contact between the air to be treated and the washing water is dramatically increased, and high removal performance is exhibited for fine particles, gaseous substances, etc., particularly fine particles having a small particle diameter (for example, 1 μm or less). Is possible. Moreover, the long fiber aggregate of this embodiment does not cause clogging and does not enter an excessive water retention state (water seal state) as compared with a general air purification filter. Therefore, for example, the final pressure loss of the medium performance filter rises to about 300 Pa, and the final pressure loss of the high performance filter rises to about 500 Pa, but the long fiber aggregate is stable at about 150 to 250 Pa. The pressure loss will not increase that much.

In the long fiber aggregate of the present embodiment, it is preferable that the bulk density (filled fiber in a fixed volume container / space and the weight of the fiber aggregate with respect to the volume) is 10 kg / m ³ or more. If the bulk density is 10 kg / m ³ or more, sufficient removal performance can be exerted on fine particles, gaseous substances and the like, as shown in Examples described later. On the other hand, when the bulk density of the long fiber assembly is increased, the increase in the differential pressure (pressure loss) becomes remarkable as shown in Examples described later. Therefore, the bulk density of the long fiber aggregate is preferably 45 kg / m ³ or less, and more preferably 30 kg / m ³ or less.

  The term “long fiber” as used herein refers to a fiber having a continuous length without being cut into several centimeters like a short fiber, and is twisted together with a monofilament made of one long fiber. And a multifilament composed of several tens of long fibers. However, the long fibers used in the present embodiment need only be crimped to form a cotton-like fiber assembly, and do not necessarily have a continuous length. Therefore, the long fiber assembly of the present embodiment may be configured by filling crimped long fibers (monofilament or multifilament) into a suitable length and then filling a container such as a mold. . The long fibers used in the present embodiment preferably have a crimp number of 7 or more / 25 mm in order to form a cotton-like fiber aggregate. The fineness (fiber diameter) is preferably 0.5 to 1000 denier, more preferably 0.5 to 100 denier. Moreover, it is preferable that a thread diameter is 5-500 micrometers, and it is more preferable that it is 5-100 micrometers.

  Examples of fibers constituting the long fiber aggregate include chemical fibers, such as regenerated fibers such as rayon, polynosic, and cupra; semi-synthetic fibers such as acetate, triacetate, and promix; acrylic, polyester, nylon, vinylon, and polyurethane. Synthetic fibers such as can be used. Since the long fiber aggregate is used as the gas-liquid contact portion 5, it is desirable that the long fiber aggregate is composed of fibers having little water absorption and chemical resistance. From such points, it is desirable to use a synthetic fiber among the above listed fibers, and it is particularly desirable to use a polyester that is not easily deformed when used in the gas-liquid contact portion 5.

  The long fiber aggregate is made from the above-mentioned chemical fibers, which are manufactured from wood and petroleum, and is spun and bundled into a long fiber bundle (tow). The entire fiber is shrunk by applying a crimp with a type crimping machine, and the fiber is loosened to form cotton. As a spinning method, a method generally used for melt spinning, dry spinning, wet spinning, gel spinning, liquid crystal spinning and the like can be used.

  In the present embodiment, from the viewpoint of being strong against moisture and having high strength, an example of a chemical fiber is given as a long fiber aggregate. However, a natural fiber may be used as long as it can be processed into cotton. As natural fiber, silk etc. can be used, for example.

  The short fiber aggregates constituting the upper layer 22 and the lower layer 23 are formed into a three-dimensional nonwoven fabric in which short fibers are processed into a curl shape and a part of the fibers are bonded to each other. The fibers processed into a curled shape of the short fiber aggregate are arranged non-uniformly, and most of the tip portion (cut portion) is located on one surface. As a result, one surface has a low density and rough (rough and rough) shape, and the other surface has a high density and flat (flat) shape. The fiber density is different in the thickness direction toward the surface. In the present embodiment, air flows from the rough and rough surface of both the upper layer 22 and the lower layer 23. That is, both the upper layer 22 and the lower layer 23 are installed in the air purification apparatus 1 so that the rough and rough surface constitutes the “lower surface” and the flat surface constitutes the “upper surface”, and each of them is an intermediate layer. 21 is adjacent.

  The fibers constituting the short fiber aggregate are not particularly limited as long as they are processed into fibers. For example, regenerated fibers such as rayon, polynosic, and cupra; semisynthetic fibers such as acetate, triacetate, and promix; acrylic Synthetic fibers such as polyester, nylon, vinylon, polyurethane, and polyvinylidene chloride can be used.

  The short fiber can be produced, for example, by crimping the fiber spun by the above-described method and then finely cutting it. Short fiber aggregate bonding methods (aggregate preparation methods) include thermal bond methods in which fibers are melted and bonded by heat, chemical bond methods in which fibers are bonded using an adhesive, and barbed needles are pierced. Examples thereof include a needle punch method for mechanically binding fibers, and any method may be used.

  In addition, since the short fiber aggregate is used as a part of the gas-liquid contact portion 5, it is desirable that the short fiber aggregate is composed of fibers that hardly absorb water and have chemical resistance. From such points, it is desirable to use polyvinylidene chloride or the like among the above listed fibers. In addition, the short fiber aggregate can vary the average fiber density as a whole depending on the fiber used, the production method, etc., but from the viewpoint of purification of the air to be treated, the short fiber aggregate should have a relatively high average fiber density. It is preferable to use it. Here, the “average fiber density” indicates how densely the fibers are arranged as a whole of the fiber assembly, and is expressed by, for example, the surface area (specific surface area) of the fiber per unit volume. .

  For example, as the short fiber aggregate described above, Saran Lock (registered trademark) of Asahi Kasei Home Products Co., Ltd. may be mentioned. Saran lock is a three-dimensional nonwoven fabric obtained by curling Saran (registered trademark) fiber, which is a highly flame-retardant fiber of the material itself, into a nonwoven fabric by curling it into a spring shape and coating and bonding with Saran latex. Saran lock is suitably used because it has a large space and surface area, low ventilation resistance, excellent filtration efficiency, and a large dust collection capacity.

  The air purification apparatus of the present invention is characterized in that a long fiber assembly in which monofilaments or multifilaments are processed into a cotton shape is used as the gas-liquid contact portion. Therefore, in the above-described embodiment, the short fiber aggregates (upper layer 22 and lower layer 23) provided adjacent to the upper side and the lower side of the long fiber aggregate (intermediate layer 21) need not necessarily be provided. Absent. However, when the short fiber aggregate is installed adjacent to the upper side of the long fiber aggregate, the cleaning water sprayed from above can be uniformly supplied to the long fiber aggregate through the short fiber aggregate. That is, the flat upper surface of the short fiber assembly is uniformly retained by promoting the dispersion of the wash water sprayed from above, and the washed water retained by the short fiber aggregate is caused by gravity and capillary action. It flows down to the lower surface side and is uniformly supplied to the lower long fiber aggregate. In addition, when the short fiber aggregate is installed adjacent to the lower side of the long fiber aggregate, the washing water retained in the long fiber aggregate is sucked into the short fiber aggregate by capillary action, and the short fiber aggregate is Water drainage is promoted by the rough and rough lower surface of the body. Therefore, it is preferable that the short fiber assembly is provided adjacent to at least one of the upper side and the lower side of the long fiber assembly, and is provided adjacent to both of them as in the above-described embodiment. It is more preferable.

  In the above-described embodiment, the case where the air introduced into the housing is applied to a so-called vertical air purification device configured to flow vertically from bottom to top in the housing will be described as an example. However, the present invention is not limited to this, and can also be applied to a so-called horizontal air purification apparatus configured such that air flows in the horizontal direction in the housing. In the horizontal type air purification device, the short fiber assembly is adjacent to the upstream side and the downstream side of the long fiber assembly (that is, the left and right sides of the long fiber assembly) with respect to the air flow direction, and a flat surface is provided. It is installed so that it faces downstream and the rough and rough surface faces upstream.

  Next, the present invention will be described in more detail with reference to specific examples.

Example 1
In this example, the removal rate of fine particles and SO _{2 in} the air was measured using the air purification device shown in FIG. A single-layer long fiber assembly is used as the gas-liquid contact portion. The long fiber assembly has a thickness of 100 mm, a fiber surface area per unit volume (specific surface area) of 2015 m ² / m ³ , and a bulk density of 29 kg / m. ³ (a mass of 125 g filled in a mold having a volume of 21 × 20.5 × 10 cm ³ and a mass of 125 g) was used. A monofilament polyester having a fineness of 17 denier, a yarn diameter of 42 μm, and a number of crimps of 7.6 / 1 inch (7.48 / 25 mm) was used as the fiber constituting the long fiber aggregate.

The processing air volume of the air to be processed flowing into the gas-liquid contact portion was 80 m ³ / h, and the water flow rate of the cleaning water from the water nozzle was 3 L / min. In this case, the ratio of the sprinkling flow rate to the treatment air volume is 2.0.

The fine particle removal rate was calculated from the fine particle concentration of the air to be treated and the fine particle concentration of the air purified by the particle counters respectively provided upstream of the intake port and downstream of the exhaust port. The inlet load at this time is 0.5 mg / m ³ for the test powder 1 type 11 of JIS Z 8901. The fine particle removal rate was measured for each particle size of the target fine particles. Similarly, the SO ₂ removal rate is calculated from the SO ₂ concentration of the air to be treated and the SO ₂ concentration of the purified air by SO ₂ concentration meters provided on the upstream side of the intake port and the downstream side of the exhaust port, respectively. did. The inlet load at this time is 0.1 mg / m ³ . The differential pressure was measured by a differential pressure gauge as a pressure difference between the upstream side of the intake port and the downstream side of the gas-liquid contact portion (between the eliminator and the blower).

(Example 2)
As the gas-liquid contact portion, the laminated structure shown in FIG. 2, that is, a laminated structure composed of an upper layer composed of short fiber aggregates, an intermediate layer composed of long fiber aggregates, and a lower layer composed of short fiber aggregates is used. The measurement was performed under the same conditions as in Example 1 except that. As the short fiber aggregates of the upper layer and the lower layer, Saran lock (product number: OM-150) having a fiber fineness of 600 to 1000 denier, a thickness of 50 mm, and a specific surface area of 360 m ² / m ³ is used, and a flat surface is used. The top surface. Moreover, the long fiber aggregate of Example 1 was used as the long fiber aggregate of the intermediate layer. Therefore, the thickness of the gas-liquid contact part of Example 2 is 200 mm.

(Example 3)
As the gas-liquid contact part, in the short fiber assembly of the upper layer and the lower layer, except for using Saran lock (product number: CS-120) having a fiber fineness of 75 denier, a thickness of 20 mm, and a specific surface area of 890 m ² / m ³ , Measurement was performed under the same conditions as in Example 2. That is, the gas-liquid contact part of Example 3 is different from the gas-liquid contact part of Example 2 in that a short fiber assembly having an average fiber density higher than that of Example 2 is used as the upper layer and the lower layer. . In addition, the bulk density of the long fiber aggregate as the intermediate layer was 29 kg / m ³ as in Example 1 (that is, the long fiber aggregate of the intermediate layer was a mold having a volume of 21 × 20.5 × 10 cm ³ . A long fiber assembly with a mass of 125 g). Moreover, the thickness of the gas-liquid contact part of Example 3 is 140 mm.

Example 4
As the gas-liquid contact portion, in the intermediate layer, the specific surface area is 967 m ² / m ³ , the bulk density is 14 kg / m ³ (the mass is 60 g filled in a mold having a volume of 21 × 20.5 × 10 cm ³ ). The measurement was performed under the same conditions as in Example 3 except that the long fiber assembly was used.

(Example 5)
As the gas-liquid contact portion, in the intermediate layer, the specific surface area is 2902 m ² / m ³ , the bulk density is 42 kg / m ³ (the volume is filled in a mold having a volume of 21 × 20.5 × 10 cm ³ , and the mass is 180 g). The measurement was performed under the same conditions as in Example 3 except that the long fiber assembly was used.

(Comparative example)
As the gas-liquid contact portion, instead of using the long fiber aggregate of the intermediate layer, a Saran lock (product number: CS-120) having a fiber fineness of 75 denier, a thickness of 20 mm, and a specific surface area of 890 m ² / m ³ was used. The measurement was performed under the same conditions as in Example 2. In addition, the thickness of the gas-liquid contact part of a comparative example is 120 mm.

  Table 1 shows the particulate removal rate and the differential pressure in Examples 1 to 3 and the comparative example.

In Examples 1 to 3, the SO ₂ removal rate is the same as that of the comparative example, but the fine particle removal rate of particles having a particle diameter of less than 1.0 μm is better than that of the comparative example. confirmed. In particular, good results were obtained in Example 1 using a single-layer long fiber assembly, and this is considered to be an effect of the long fiber assembly of the present embodiment. Moreover, in Examples 1-3, although the fiber assembly (long fiber assembly) whose average fiber density is very higher than the fiber assembly (short fiber assembly) of a comparative example is used, it is not so much. No increase in differential pressure was observed.

  Next, Table 2 shows the particulate removal rate and the differential pressure in Examples 3 to 5.

  In Example 4, the fine particle removal rate is not as high as that of Example 3, but better results are obtained as compared with the comparative example (see Table 1). It was confirmed that the same good results were obtained. In Example 5, the fine particle removal rate was as good as that in Example 3, but a significant increase in the differential pressure was observed. This is considered to be because in Example 5, the bulk density of the long fiber aggregates was increased and the water retention state was advanced. Therefore, when Example 5 is compared with Example 3, Example 3 is better in terms of this differential pressure.

DESCRIPTION OF SYMBOLS 1 Air purification apparatus 2 Housing | casing 3 Intake port 4 Exhaust port 5 Gas-liquid contact part 6 Sprinkling nozzle 7 Circulation tank 8 Circulation pump 9,13,14 Piping 10 External water source 11 Water supply valve 12 Drain valve 15 Eliminator 16 Blower 21 Middle layer 22 Upper layer 23 Lower layer

Claims (7)

An intake port and an exhaust port provided in the housing;
A gas-liquid contact portion that is provided between the intake port and the exhaust port, and in which air introduced into the housing from the intake port contacts the cleaning water;
Sprinkling means that is provided above the gas-liquid contact portion and sprays the washing water onto the gas-liquid contact portion;
Have
The gas-liquid contact portion has a filling portion filled with a fiber assembly in which a monofilament or a multifilament having a fineness of 0.5 to 100 denier is processed into a cotton shape,
The air purification apparatus, wherein the fiber assembly filled in the filling portion has a specific surface area of 900 to 5000 m ² / m ³ and a bulk density of 10 kg / m ³ or more and 45 kg / m ³ or less. Before Ki繊維集coalescence, the monofilaments or multifilament are crimped fiber aggregate, an air purification device according to claim 1. Before Ki繊維集coalesce, formed of the monofilament or the multifilament chemical fiber, air purification device according to claim 1 or 2. Before Ki繊維集coalesce, formed of the monofilament or the multifilament synthetic fibers, air purification device according to claim 3. The air purification device according to claim 4 , wherein the synthetic fiber is polyester. The gas-liquid contact part is provided adjacent to the filling part and at least one of the upstream side and the downstream side of the filling part with respect to the air flow direction, and is another mat-like one having a different fiber density in the thickness direction . The air purification device according to any one of claims 1 to 5 , wherein the air purification device has a laminated structure with a fiber assembly. The air purification device according to claim 6 , wherein the another fiber assembly is a non-woven fabric in which short fibers processed into a curled shape are bonded to each other.