JPH09123166A - Apparatus for treating waste plastics - Google Patents

Abstract

PROBLEM TO BE SOLVED: To exhaust waste hot air after catalytic combustion by the use of an ordinary exhaust system. SOLUTION: A waste plastic treating apparatus 10 comprises an exhaust cooling part 110 provided therein, and an exhaust pipe 96 being inserted in a merging pipe 122 of the exhaust cooling part 110. Also, the merging pipe 122 communicates with the interior part of the apparatus main body 12 via a scroll vent pipe 118 and hood part 112, and activation of driving means 120 allows air W5 flowed in the apparatus main body 12 from the vent hole 126 to be taken in the merging pipe 122. The combustion waste hot air W4 subjected to catalytic combustion by the catalytic combustion part 86 and sent in the merging pipe 122 passing through the exhaust pipe 96 is mixed with air W5 within the merging pipe 122, and discharged outside after sufficient cooling. Thus, even in the case of conducting exhaust by employing a collection duct, exhaust can be done with exhaust gas from other systems without impairing the duct.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste plastic processing apparatus for supplying high temperature hot air to waste plastic to heat and melt it.

[0002]

2. Description of the Related Art As a waste plastic processing apparatus, there is a waste plastic processing apparatus that crushes waste plastic and heat-melts the crushed waste plastic.

In this type of waste plastic processing apparatus, a crusher having a built-in cutter is provided, and the waste plastic that has been put into the crusher is crushed by the cutter, and the waste plastic is conveyed to a melting machine provided in the crusher. To do. This melting machine is provided with a heating and melting processing section, and is further equipped with a burner. The waste plastic after being crushed and conveyed into the melting machine is heated and melted by high-temperature hot air from the burner, and the melted waste plastic falls from the dropping port of the melting machine and is stored in a container and cooled and solidified.

Further, this type of waste plastic processing apparatus is provided with a catalytic combustion section made of platinum, ceramics or the like. Exhaust hot air after heating and melting the waste plastic is fed to the catalytic combustion unit to remove the malodor and toxic components generated during the melting of the waste plastic from the exhaust hot air. In this state, the exhaust hot air is non-toxic and odorless and can be exhausted to the outside (outdoor).

[0005]

By the way, when exhausting the exhaust hot air after being treated in the catalytic combustion part to the outside, it is necessary to use the collective duct to exhaust it to the outside (outdoors) together with the exhaust gas from other equipment. Is preferred.

However, the temperature of this exhaust hot air is about 40.
It is very high, around 0 degrees, and it is difficult to exhaust the exhaust hot air through a normal collecting duct. For this reason, a duct for exhaust hot air is provided separately from the duct for other equipment, or
It is necessary to give heat resistance to the collecting duct itself in advance to deal with this. However, in any case, there is a problem in terms of piping work and equipment cost, and therefore, a waste plastic processing device capable of solving this problem has been earnestly desired.

In consideration of the above facts, an object of the present invention is to obtain a waste plastic processing apparatus capable of exhausting the exhaust hot air after catalytic combustion with a normal exhaust facility.

[0008]

According to a first aspect of the present invention, there is provided a waste plastic processing apparatus, wherein a hot air source for generating high temperature hot air capable of melting waste plastic and the high temperature hot air from the hot air source are taken in and the waste is discarded. A remelting unit for melting and processing the plastic, and a low-temperature exhaust hot air after melting the waste plastic is re-fed to the hot air generating source and reheated by the heat of the hot air generating source to be high temperature exhaust hot air. Part, a catalyst combustion part for catalytically burning the high-temperature exhaust hot air after being reheated by the reheating part, and a downstream side of an exhaust pipe through which the combustion exhaust hot air after catalytic combustion by the catalytic combustion part flows An exhaust cooling unit capable of taking in air outside the apparatus main body and mixing the combustion exhaust hot air with the air to dilute and cool the combustion exhaust hot air.

In the waste plastic processing apparatus having the above structure,
High-temperature hot air from the hot-air source is sent to the melting treatment section, and the high-temperature hot air heats the waste plastic to perform melting treatment.

Further, the low-temperature exhaust hot air after melting the waste plastic is sent to the reheating section to become high-temperature exhaust hot air by the heat of the hot air source, and then sent to the catalytic combustion section for catalytic combustion. In this catalytic combustion unit, the bad odor and toxic gas of the hot exhaust hot air generated when the waste plastic is melted are removed. As a result, the combustion exhaust hot air after catalytic combustion is made nontoxic and odorless.

Further, the catalytically combusted combustion exhaust hot air is sent to the exhaust cooling unit. The exhaust cooling unit takes in air from the outside of the apparatus body and mixes the air with the combustion exhaust hot air. Here, the combustion exhaust hot air is diluted by being mixed with air, sufficiently cooled and exhausted to the outside (outdoor).

In the waste plastic processing apparatus according to a second aspect of the present invention, the exhaust cooling unit is characterized in that the inside communicates with the inside of the apparatus main body, and the air is taken in after passing through the inside of the apparatus main body.

In the waste plastic processing apparatus having the above structure,
The air for cooling the combustion exhaust hot air passes through the inside of the apparatus main body and is then taken into the exhaust cooling unit.

Here, when the air passes through the inside of the main body of the apparatus, the air cools a motor for driving the apparatus installed inside the main body of the apparatus, and therefore a special cooling facility for cooling these parts and the like. Is unnecessary.

Further, as the air passes through the inside of the main body of the apparatus, the air takes in the exhaust gas before deodorization that leaks from the joint portion inside the main body of the apparatus, so that the leakage of the exhaust gas to the outside of the apparatus is prevented.

[0016]

FIG. 1 is a sectional view showing the overall structure of a waste plastic processing apparatus 10 according to an embodiment of the present invention. FIG. 2 shows a part of the waste plastic processing apparatus 10. A rear view, broken away, is shown. Also,
FIG. 3 shows a front view in which the waste plastic processing apparatus 10 is partially broken. In these drawings, the arrow X indicates the front in the depth direction of the waste plastic processing apparatus 10, and the arrow Y indicates the right side in the width direction of the waste plastic processing apparatus 10. Further, the arrow Z indicates the upper side in the height direction of the waste plastic processing apparatus 10.

The waste plastic processing apparatus 10 has a box-shaped apparatus body 12 as a whole.
An input port 14 is provided on the upper part of the front surface of and the opening / closing lid 15 is attached. Inside the apparatus main body 12, each processing unit such as a crushing unit 16, a preheating unit 18, a melting processing unit 20, a housing unit 22 and a hot air supply unit 24 is arranged, and each processing unit is adjacent to each other and is separated by a partition wall. It is isolated.

The coarse crushing section 16 is located on the rear side of the charging port 14 and is composed of a rotary blade 26 and a fixed blade 28.
0 is arranged. A plurality of rotary blades 26 are fixed at regular intervals along the longitudinal direction of a horizontal shaft 32 rotatably supported on a partition wall on the side of the crushing section 16. The shaft 32 is rotationally driven by a motor (not shown) arranged in the apparatus main body 12, whereby the rotary blade 26 is rotated. On the other hand, the fixed blade 28 is fixed corresponding to the rotary blade 26 so that the rotary blade 26 can be inserted. Therefore, when the rotary blade 26 is rotated,
The waste plastic P is roughly crushed between the rotary blade 26 and the fixed blade 28.

A preheating section 18 is disposed on the rear side of the crushing section 16 (cutter 30). The preheating section 18 is located near the crushing section 16 and communicates with the preheating section 18.
The waste plastic P crushed by is sent in.

An exhaust chamber 34 is provided above the preheating section 18 and in the vicinity of a corner opposite to the charging port 14. The exhaust chamber 34 includes the crushing unit 16 communicating with the preheating unit 18 and the exhaust hole 3
6 through which the air in the preheating section 18 can flow. A filter 38 is attached to the exhaust hole 36.

A blower 40 is arranged in the exhaust chamber 34. The blower 40 has a pair of fans 42 and 44. A feed pipe 46 is connected to the fan 42, and a feed pipe 48 is connected to the fan 44. Accordingly, the blower 40 can distribute the air from the preheating unit 18 into a predetermined amount and independently supply the air.

The shaft 1 for rotating the fans 42, 44
00 is axially supported by the bearing portion 98 of the partition wall 45, and one end of the shaft 100 projects outward from the partition wall 45.
A pulley 104 is provided at the tip of the shaft 100 on the side where the partition wall 45 projects outward. A motor 106 having a pulley 108 is installed between the partition wall 45 below the pulley 104 and the outer wall 12A. These pulleys 1
04 and the pulley 108 are wound around an endless belt 109. When the motor 106 is operated, the fans 42, 4 are passed through the pulley 108, the endless belt 109, and the pulley 104.
4 rotates.

The side wall 12A on the side of the motor 106 is also provided.
A plurality of slit-shaped ventilation holes 126 are formed in the. Air (outside air) is allowed to flow into the ventilation holes 126 from the outside of the apparatus main body 12, and thus the motor 106 can be cooled.

On the other hand, below the preheating section 18, a melting processing section 20 is provided. Inside the melting processing unit 20, there is provided a quadrangular pyramid-shaped melting furnace 50 that converges downward. A dropping port 52 is formed at the lower end of the melting furnace 50, and a hot air introducing port 54 which is elongated in the horizontal direction is formed in the furnace wall.
Are formed in large numbers. A hot air inlet cover plate 56 is formed at the upper end of the hot air inlet 54 so as to project obliquely downward toward the inside of the melting furnace 50, and the waste plastic P dropped from above is used as the hot air inlet. 54 to melting furnace 5
It prevents it from jumping out of 0. Further, a hot air stagnation chamber 58 is formed between the melting furnace 50 and the partition wall 47 of the melting processing section 20.

A container 22 for cooling and solidifying the molten waste plastic P is provided immediately below the melting processor 20 (melting furnace 50). Inside the accommodation section 22,
The container 6 is placed on a receiving plate 62 that is movable by a hinge 60.
No. 4 is mounted thereon, and the waste plastic P flowing down from the dropping port 52 of the melting furnace 50 is accommodated therein.
Further, a sensor 66 is arranged corresponding to the tip of the receiving plate 62, and it is possible to detect that the waste plastic P housed in the container 64 has reached full capacity.

Further, the melting processing section 20 (hot air stagnation chamber 58)
On the front side of the and below the inlet 14, the hot air feeding unit 24
Is arranged. The hot air supply unit 24 includes a substantially cylindrical furnace 68, and the furnace 68 serves as the melting treatment unit 20.
Is connected to the hot air stagnation chamber 58. A burner 70 as a hot air source is attached to the partition wall of the furnace 68, and a fuel tank 71 is arranged below the burner 70. A tip portion of the burner 70 projects into the furnace 68, and a combustion furnace 72 is fixed in the furnace 68 so as to cover the tip of the burner 70. The combustion furnace 72 is formed in a cylindrical shape, and has a pair of shield plates 74, 7 inside.
6 are arranged. These shield plates 74, 76 and the bottom wall 72A of the combustion furnace 72 have through holes 78, 80,
A feeding hole 82 is formed. This allows the burner 70
The air heated by is sent from the furnace 68 to the hot air stagnation chamber 58 after passing through the through holes 78 and 80 and the feed hole 82, and further passes from the hot air stagnation chamber 58 to the hot air introduction port 54 and the melting furnace 50. It is supposed to be sent inside.

Further, a feed pipe 48 is connected to the furnace 68. Therefore, the blower 40 distributes and sends the air from the preheating section 18 into the furnace 68. On the other hand, the above-described feed pipe 46 is spirally wound around the outer periphery of the combustion furnace 72, and constitutes the reheating unit 84. Therefore, the blower 40 allows the preheating unit 18
The air distributed from is sent to the reheating unit 84, and is reheated by the heat from the combustion furnace 72 in the reheating unit 84.

A catalytic combustion unit 86 is arranged near the upper side of the hot air supply unit 24. The catalytic combustion unit 86 is connected to the above-described reheating unit 84 (feed pipe 46) via a connecting pipe 88, and the air heated in the reheating unit 84 is fed therein. As shown in FIG. 3, the catalytic combustion section 86 is composed of a pair of ceramic sections 90, 92 and a platinum section 94 arranged between these ceramic sections 90, 92, and is fed by a connecting pipe 88. It can catalytically burn air. Further, the catalytic combustion unit 86 is connected to the exhaust cooling unit 110 installed on the ceiling wall 12B of the apparatus body 12 via the exhaust pipe 96, and the air after catalytic combustion is sent to the exhaust cooling unit 110. It

Here, FIG. 4 shows a front view in which the exhaust cooling unit 110 is partially broken, and FIG. 5 shows a plan view of the exhaust cooling unit 110. As shown in these drawings, the exhaust cooling unit 110 includes a hood portion 112. The hood portion 112 is formed in a quadrangular pyramid shape that converges upward. Further, the inside of the hood 112 is hollow, and the lower end side is open. In a state where the hood portion 112 is installed on the ceiling wall 12B of the device body 12, a rectangular ventilation hole 114 formed in the ceiling wall 12B,
The hood portion 112 covers 116 from above.
Here, since the ventilation holes 114 and 116 are formed so as to be respectively located between the outer wall 12A and the partition wall 45, the inside of the hood portion 112 is provided inside the device main body 12 through the ventilation holes 114 and 116. It communicates with the space between 12A and the partition wall 45, and the air taken in from the ventilation hole 126 can pass between the outer wall 12A and the partition wall 45 and flow into the inside of the hood portion 112.

Further, the hood portion 112 has a spiral ventilation pipe 1
18 are connected. A spiral ventilation path (not shown) is formed inside the spiral ventilation pipe 118, and air from the hood 112 flows spirally from the central portion of the spiral ventilation pipe 118 to the outer peripheral portion. Is. Further, a driving unit 120 is installed on the side of the central portion of the spiral ventilation pipe 118. The drive unit 120 includes a motor and a fan (both not shown). When the motor is driven, the fan rotates to reduce the internal pressure in the hood 112 and guide air into the spiral ventilation pipe 118. Then, this air can further flow to the outer peripheral side of the spiral ventilation pipe 118.

Further, the outer peripheral side end portion (that is, the downstream side end portion) of the spiral ventilation pipe 118 is connected to the outside air entrance portion 124 of the merging pipe 122. The merging pipe 122 is closed at the lower end, and the air that has passed through the spiral ventilation pipe 118 and is fed to the merging pipe 122 is guided to the upper end side of the merging pipe 122. Further, from the lower end side of the confluent pipe 122, an exhaust pipe 96 penetrating the ceiling wall 12B of the apparatus main body 12 is formed.
Is inserted up to a position on the upper end side of the outside air entrance portion 124, and the air that has passed through the outside air entrance portion 124 and is guided to the upper end side of the merge pipe 122 at this portion joins the air flowing through the exhaust pipe 96. This is the configuration.

Next, the operation of this embodiment will be described. In the waste plastic processing apparatus 10 having the above structure, when waste plastic P such as styrene foam, polyethylene, polyvinyl chloride, polypropylene, etc. is charged into the crushing section 16 from the charging port 14, the rotary blade 26 rotated by the motor and the fixed blade. Between 28 and these waste plastics P
Is sandwiched and coarsely crushed.

The crushed waste plastic P is used in the crushing section 1
It is sent to the preheating section 18 directly communicating with 6, and further falls into the melting furnace 50 of the melting processing section 20. In the melting furnace 50, a predetermined amount of roughly crushed waste plastic P is deposited.

On the other hand, in the hot air feeding section 24, the air is burner.
High temperature hot air W heated by 70 ₁(Eg 280
℃). This high temperature hot air W₁Through holes 78, 8
0, the hot air stagnation chamber 58 from the furnace 68 after passing through the feeding hole 82
To the hot air stagnation chamber 58
It is fed into the melting furnace 50 through 54 (at this point
Is high temperature hot air W₁Is, for example, about 235 ° C.). Also,
At the same time, high temperature hot air W ₁Heats the furnace wall itself of the melting furnace 50
I do. Therefore, the waste plastic P has high temperature hot air W₁
Direct heating action by the
It is melted by the indirect heating action of the heat. Dissolution
The melted waste plastic P is stored in the melting furnace 50 by its own weight.
It flows down from the drop opening 52 into the accommodation section 22. To accommodation section 22
The melted waste plastic P that has flowed down is stored in the container 64.
It collects and is naturally air-cooled and solidified here.

On the other hand, the exhaust gas such as the gas generated from the waste plastic P during melting, that is, the low-temperature exhaust hot air W ₂ in the preheating section 18 flows into the exhaust chamber 34 through the filter 38 of the exhaust hole 36 (this At the time, low temperature exhaust hot air W
₂ is distributed by the blower 40 and is fed independently by the feed pipe 46 and the feed pipe 48, respectively.

Of the _two low-temperature exhaust hot air W ₂ distributed, one low-temperature exhaust hot air W fed by the feed pipe 48.
₂₁ is re-introduced into the furnace 68 as secondary air, and is heated by the burner 70 to generate high-temperature hot air W ₁ inside the furnace 68.
It is completely burned with it and reused.

Further, the other low temperature exhaust hot air W ₂₂ fed by the feed pipe 46 reaches the reheating section 84 which is spirally wound around the outer periphery of the combustion furnace 72, and in the reheating section 84. It is heated again by the heat from 72 to become high temperature exhaust hot air W ₃ (for example, about 250 ° C.). Then, the hot exhaust hot air W ₃ passes through the connecting pipe 88 and passes through the catalytic combustion unit 86.
Sent to

In the catalytic combustion unit 86, the hot exhaust hot air W ₃ is catalytically burned to burn the exhaust hot air W ₄ (for example, about 380 ° C.).
It is said. That is, for example, when the expanded polystyrene used in a fish box for packing fish is treated as the waste plastic P, chlorine, nitrogen oxides, sulfur oxides, etc. are removed by the ceramic parts 90, 92, and further, Styrene, which causes a bad smell and is a toxic component, is combined with oxygen by the platinum portion 94 and decomposed into carbon dioxide and water. The combustion exhaust hot air W ₄ after catalytic combustion in the catalytic combustion section 86 is harmless and odorless because it is carbon dioxide and water as described above.

Further, the combustion exhaust hot air W ₄ passes through the exhaust pipe 96 and is sent into the merging pipe 122 of the exhaust cooling unit 110.

On the other hand, in the exhaust cooling unit 110, the waste plastic
The drive unit 12 by operating the clock processing device 10.
The 0 motor is activated and the fan is rotated. This
Therefore, the internal pressure of the hood portion 112 is reduced. Where the figure
2, the inside of the hood portion 112 and the apparatus main body
The inside of 12 is communicated with ventilation holes 114 and 116.
Therefore, the air taken in from the vent holes 126 (outside
Qi) W_FiveAfter passing between the outer wall 12A and the partition wall 45
Introduced into the hood 112 through the ventilation holes 114 and 116.
Be led. Next, the air introduced into the hood portion 112
W_FiveIs driven by the fan of the drive unit 120.
8 and is fed into the merging pipe 122. Sa
In addition, as shown in FIG.
Air W _FiveFlows in the exhaust pipe 96 and flows into the merging pipe 122.
Combustion exhaust hot air W_FourAnd is mixed above the exhaust pipe 96
You. Here, the combustion exhaust hot air W_FourIs the air W_FiveMixed with
The diluted exhaust hot air W that has been diluted and sufficiently cooled₆
Becomes

Here, according to the result of the experiment conducted by the applicant of the present application, the outside air temperature (that is, the temperature of the air W ₅ ) is 2
When the temperature of the combustion exhaust hot air W ₄ was 382 ° C. at 7 ° C., the temperature of the diluted exhaust hot air W ₆ was 74 ° C.

Even when the diluted exhaust hot air W ₆ thus cooled is passed through normal exhaust equipment such as a collecting duct, the exhaust hot air W ₆ is not damaged outside the exhaust equipment (outdoors). Can be exhausted to.

Further, since the air W ₅ passes between the outer wall 12A and the partition wall 45 when taken into the hood portion 112, the motor W is cooled by the air W ₅ . Therefore, cooling equipment for the motor 106 such as water cooling equipment is not required.

Further, the air W ₅ is supplied to the outer wall 12A and the partition wall 45.
When passing between the low-temperature waste hot air W ₂ leaking from the bearing portion 98 is taken by the air W _5, to be induced with the air W ₅ into the receptacle 112, low-temperature waste hot air W
_{It is possible} to prevent the _second device body 12 from leaking to the outside.

As described above, in the waste plastic processing apparatus 10, the combustion exhaust hot air W ₄ processed by the catalytic combustion unit 86 is mixed and diluted with the air W ₅ by the exhaust cooling unit 110 to be cooled and diluted hot exhaust air W. _Since it is configured to exhaust after setting to ₆ , it is possible to exhaust to the outside with normal exhaust equipment such as a collecting duct, and it is possible to reduce the cost required for the exhaust equipment and the like.

Since the air W ₅ is taken into the exhaust cooling section 110 after passing through the inside of the apparatus main body 12, the motor 10
6 and the like can be cooled, a special facility for cooling the motor 106 is not required, and the life of the motor 106 can be extended.

Further, when the air W ₅ passes through the inside of the apparatus main body 12, the air W ₅ takes in the low temperature exhaust hot air W ₂ leaking from the bearing portion 98 etc. and flows to the exhaust cooling section 110. It is possible to prevent the low temperature exhaust hot air W ₂ from leaking to the air.

In the present embodiment, the air W ₅ flows into the hood portion 112 after passing through the inside of the apparatus main body 12, but in the case where equipment for cooling the motor 106 is separately provided, etc. When it is not necessary for the air W ₅ to pass through the inside of the apparatus main body 12, the air W ₅ may be directly taken in from the exhaust cooling unit 110.

Further, in the present embodiment, the exhaust cooling section 11
Although the drive unit 120 is provided at 0 and the air W ₅ is guided by the motor and the fan, the drive unit 120 is not always necessary. That is, when the flow speed of the combustion exhaust hot air W ₄ is relatively high, the air W ₅ is naturally mixed with the combustion exhaust hot air W _{4 due} to the pressure difference generated at the confluence of the combustion exhaust hot air W ₄ and the air W _5. The same effects as those described above can be obtained without providing the driving unit 120.

[0050]

As described above, in the waste plastic processing apparatus according to the first aspect, since the exhausted hot air that has been diluted and cooled can be exhausted by using the collective duct that joins with the duct of the other equipment, special equipment is required. Therefore, the equipment cost can be reduced. Further, since it is only necessary to provide the exhaust cooling unit, the size of the device itself does not increase.

In the waste plastic processing apparatus according to the second aspect, the air for diluting and cooling the combustion exhaust hot air can be used for cooling the parts such as the motor installed in the main body of the apparatus, and for cooling these parts. No special equipment is required, and the overall size of the device can be reduced. When the air passes through the inside of the apparatus main body, since the exhaust gas before deodorization leaking from the joint portion inside the apparatus main body is taken in, the leakage of the exhaust gas to the outside of the apparatus can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a waste plastic processing device according to an embodiment of the present invention.

FIG. 2 is a partially cutaway rear view of the waste plastic processing apparatus according to the embodiment of the present invention.

FIG. 3 is a partially cutaway front view of the waste plastic processing apparatus according to the embodiment of the present invention.

FIG. 4 is a partially cutaway front view of an exhaust cooling unit of a waste plastic processing apparatus according to an embodiment of the present invention.

FIG. 5 is a plan view of an exhaust cooling unit of the waste plastic processing apparatus according to the embodiment of the present invention.

[Explanation of symbols]

10 Waste plastic processing device 12 Main body 70 Burner (hot air source) 20 Melting processing part 84 Reheating part 86 Catalyst combustion part 96 Exhaust pipe 110 Exhaust cooling part P Waste plastic W ₁ High temperature hot air W ₂₂ Low temperature hot exhaust air W ₃ High temperature exhaust Hot air W ₄ Combustion exhaust hot air W ₅ Air

Claims (2)

[Claims] 1. A hot air source for generating high-temperature hot air capable of melting waste plastic, a melt processing section for taking in the high-temperature hot air from the hot air source and melting the waste plastic, and melting the waste plastic. After reheating, the low-temperature exhaust hot air is re-fed to the hot-air generating source and reheated by the heat of the hot-air generating source to become high-temperature exhaust hot air, and the high-temperature exhaust after reheating by the reheating unit. The catalyst burner for catalytically burning hot air, and the combustion exhaust hot air after catalytic combustion by the catalyst burner are installed on the downstream side of the exhaust pipe, and are capable of taking in air outside the main body of the apparatus. A waste plastic processing device comprising: an exhaust cooling unit that mixes hot air and the air to dilute and cool the combustion exhaust hot air. 2. The waste plastic processing apparatus according to claim 1, wherein the exhaust cooling unit has an inside communicating with the inside of the apparatus main body, and takes in the air after passing the inside of the apparatus main body.