JPH0130060B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an air conditioner for supplying clean air with temperature control or humidity control at the same time as temperature control into a relatively large air supply painting booth for painting automobiles, etc. Regarding equipment.

[Prior art and its problems]

In the case of large air supply painting booths where automobile painting is carried out, clean air that is controlled by an air conditioner to a temperature of around 25°C and a humidity of around 70 to 80% is supplied.
Approximately 7200 per painting booth width 6m and length 50m
m ³ /min.

Therefore, heaters, coolers, etc. of the air conditioner that regulates the temperature and humidity of the outside air and supplies clean air to the coating booth need to have a large capacity, which increases equipment costs. There is a problem in that running costs increase in summer and winter when there is a large temperature difference between the clean air supplied into the booth and the outside air sent into the air conditioner.

Therefore, in the past, a heat exchanger was installed to exchange heat between the outside air sent into the air conditioner and the exhaust gas discharged from the painting booth, reducing the amount of heat required by the air conditioner's heater, cooler, etc. We are trying to save energy by reducing the
57-165063).

By the way, in order to increase the energy saving effect in this way, as shown in Japanese Patent Application Laid-Open No. 57-165063, it is necessary to separate the flow path for the outside air sent into the air conditioner and the flow path for the exhaust gas discharged from the painting booth. Heat exchange efficiency is improved by using a total heat exchanger with a rotating heat storage body (i.e., a rotor using a moisture absorbing material) that rotates transversely to recover total heat (enthalpy) by recovering latent heat as well as sensible heat. It is desirable to improve.

However, since the rotor of this total heat exchanger is formed into a honeycomb structure with a large number of ventilation holes each having a diameter of several millimeters, over time, the inside of each ventilation hole becomes large due to the exhaust gas from inside the paint booth. Paint mist, organic solvents, or dust contained in the air conditioner may adhere to the air conditioner, and dust contained in the outside air sent to the air conditioner may also adhere to the air conditioner, resulting in a significant decrease in heat exchange efficiency and rendering it unusable. It had drawbacks.

For example, according to experiments conducted by the present inventors, if the concentration of paint mist in 5000 m ³ /min of air sucked and discharged from inside the painting booth to the floor below is 0.1 g/m ³ , then Even if 99.9% of the paint mist was removed from the air through gas-liquid contact through the ventilator in the mist processing chamber under the floor, there would still be 5000% of the paint mist in the exhaust gas discharged to the outside.
m ³ /min x 0.1g/min x 0.001 x 60 = 30g/hr of paint mist is included, so if the booth's daily operating time is 16 hours, the amount of paint mist will be 30g/hr per day.
The results show that approximately 480 g of paint mist (g x 16 = 480 g) adheres to the rotor, causing an immediate drop in heat exchange efficiency.

For this reason, in the past, in order to prevent paint mist from adhering to the rotor of the heat exchanger,
As described in JP-A No. 55-3888, the exhaust duct of the painting booth is equipped with a large number of cleaning devices and filter devices for purifying paint mist, organic solvents, dust, etc., as well as continuous organic solvent adsorption/desorption devices, etc. I'm trying to clean the exhaust air by letting it run.

However, in this way, 5000m ³ /
If cleaning equipment, filter equipment, etc. are installed to process a large amount of exhaust gas, the running cost of these equipment alone will be enormous, which is a disadvantage. It was not possible to completely prevent it.

[Purpose of the invention]

Therefore, the present invention eliminates the need to install various cleaning devices, filter devices, etc. that increase running costs in the exhaust duct that exhausts the air in the paint booth during supply, and eliminates the need to install paint mist contained in the exhaust duct. It is an object of the present invention to provide an air conditioning system for a paint booth with a supply air supply system that can reliably prevent organic solvents, dust, etc. from adhering to the rotor of a total heat exchanger and reducing heat exchange efficiency.

[Structure of the invention]

In order to achieve this objective, the present invention pushes clean air supplied from an air conditioner that controls the temperature of outside air into a painting booth, and sucks this air together with paint mist and evaporated organic solvents inside the painting booth into the floor. In an air conditioner for a painting booth, the air supplied to the air conditioner is separated and removed by gas-liquid contact, and then discharged to the outside from an exhaust duct. A rotor of a total heat exchanger that exchanges heat with the exhaust gas is arranged to rotate while crossing the flow path of the outside air and the exhaust gas, and the rotor is arranged so as to rotate while crossing the flow path of the outside air and the exhaust gas. An injection nozzle for injecting high-pressure water is disposed in the ventilation hole of the rotor, and the injection nozzle is configured to reciprocate between the center and the peripheral edge of the rotor.

[Action of the invention]

According to the present invention, the rotor of the total heat exchanger rotates while crossing the flow path of the outside air sent into the air conditioner and the flow path of the exhaust gas discharged from the exhaust duct of the paint booth. An injection nozzle is provided, and the injection nozzle is configured to reciprocate between the center and the peripheral edge of the rotor while ejecting high-pressure water, thereby preventing paint mist and organic solvents from adhering to the rotor's ventilation holes. , dust is automatically and sequentially wiped away over the entire surface of the rotor.

Furthermore, in the present invention, instead of the conventional passive means of reducing the amount of paint mist adhering to the rotor using a cleaning device or filter device installed in the exhaust duct, the entire surface of the rotor is removed. Since paint mist, etc. is actively wiped off by direct cleaning with high-pressure water, it is possible to remove not only paint mist in the exhaust, but also dust in the outside air fed into the air conditioner, if it adheres to the rotor. These can be completely wiped off to maintain extremely high heat exchange efficiency.

〔Example〕

Figure 1 is a flow sheet diagram showing the supply coating booth and its air conditioning equipment, Figures 2 and 3 are front and rear perspective views of the total heat exchanger that constitutes the main part, and Figure 4. is a partial cross-sectional view of the total heat exchanger.

In the figure, reference numeral 1 denotes a supply painting booth for painting automobiles, which includes an air supply chamber 4 into which clean air is supplied by a blower fan 3 from an air conditioner 2 that controls the temperature and humidity of the air, and an air supply chamber 4. a painting booth 6 into which clean air is forced from a chamber 4 through a filter 5 at a predetermined wind speed;
It consists of a mist processing chamber 8 that sucks the air inside the painting booth 6 along with paint mist, evaporated organic solvent, etc. below the floor surface 7 made of a rectifier plate, and the air sucked into the mist processing chamber 8 is passed through a ventilator section 9. After paint mist and the like are separated and removed by gas-liquid contact, they are discharged to the outside through an exhaust duct 11 having an exhaust fan 10.

The air conditioner 2 also includes a primary filter 14 and a secondary filter 15 that remove dust from the outside air introduced from the air supply gear rally 13 into the air conditioning room 12.
A humidifier 16 that humidifies outside air purified through filters 14 and 15, a cooler 17, an eliminator 18, and a heater 19 are connected in series.

And the air conditioning room 12 between the filters 14 and 15
The upper and lower or left and right halves of the rotor 21 of the total heat exchanger 20 are respectively interposed in the exhaust duct 11 which is disposed in parallel along the upper and lower sides or the left and right sides of the air-conditioned room 12. It is configured to rotate at a low speed, for example, about 8 to 10 times per minute, while crossing a flow path _F1 for outside air sent into the device 2 and a flow path _F2 for exhaust gas discharged from the exhaust duct 11. There is.

The rotor 21 is formed into a honeycomb structure using, for example, an aluminum plate having a porous aluminum oxide layer that acts as a moisture absorber, and has an opening in the direction of the rotating shaft 22 with a diameter of about 2 mm.
It has a large number of ventilation holes 23, 23, . . .

Further, as shown in FIGS. 2 to 4, the total heat exchanger 20 faces one side of the rotating rotor 21 and is directed into the ventilation hole 23 of the rotor 21 by about 90 to
A spray nozzle 24 for spraying high-pressure water of about 100 kg/cm ² is provided, and an air nozzle 25 for spraying high-pressure air is integrally attached to the spray nozzle 24 in parallel therewith.

26 is a feed screw rod to which the injection nozzle 24 is attached and reciprocates between the center and the peripheral side of the rotor 21, and both ends are rotatably supported on the center side and the peripheral side of the rotor 21, A gear motor 27 is connected to the end on the peripheral side and is configured to be driven to rotate in forward and reverse directions at a predetermined timing.

28 is a water trap that receives and collects high-pressure water injected from the injection nozzle 24 from the other side of the rotor 21, and 29 is a drain pipe that discharges the water collected in the water trap 28.

The above is an example of the configuration of the air conditioning equipment for the supply coating booth according to the present invention, and the operation and effects thereof will be explained next.

Clean air whose temperature and humidity are controlled in the air-conditioned room 12 of the air conditioner 2 by the humidifier 16 , the cooler 17 , and the heater 19 is sent to the air supply duct 30 by the blower fan 3 .
Air is fed into the air supply chamber 4 of the coating booth 1 through the filter 5 and pushed into the coating booth 6 through the filter 5. The air pushed into the painting booth 5 is caused to flow down inside the booth 6 at a predetermined wind speed, and the paint mist generated by spray painting on the automobile body 31,
A mist processing chamber 8 under the floor 7 along with evaporated organic solvents, etc.
sucked inside. In the mist processing chamber 8, the air sucked under the floor is passed through the ventilator section 9, where most of the paint mist and the like are separated and removed by gas-liquid contact, and then exhausted to the outside through the exhaust duct 11.

At this time, a flow path F ₁ of outside air sent from the supply air gear rally 13 into the air conditioning chamber 12 of the air conditioner 2;
Since the rotor 21 of the total heat exchanger 20 is rotated across the flow path F ₂ of the exhaust gas discharged from the exhaust duct 11, the rotor 21 loses heat on the exhaust duct 11 side in winter, for example. The outside air is heated and humidified by supplying heat and dissipating the heat on the air conditioned room 12 side.

This significantly reduces the amount of heat required by the cooler 17, heater 19, etc. installed in the air conditioner 2, which controls the temperature and humidity of a large amount of outside air and sends it to the paint booth 1, resulting in energy savings. can be achieved.

In particular, in the rotor 21 in which a large number of ventilation holes 23 are formed from an aluminum plate having a porous aluminum oxide layer having hygroscopic properties, latent heat is recovered together with sensible heat, resulting in total heat recovery. The heat exchange efficiency is extremely high compared to the case where a heat exchanger or the like is used, and the running cost of the air conditioner 2 can be significantly reduced.

Next, the exhaust gas discharged from the exhaust duct 11 contains trace amounts of paint mist, organic solvents, etc. that were not removed in the mist treatment chamber 8, and are also sent into the air conditioning room 12 from the air supply gear rally 13. The outside air also contains dust that was not removed by the primary filter 14.

Therefore, these paint mist, organic solvent, dust, etc. tend to adhere little by little into each vent hole 23 of the rotor 21 over time.

Here, in the present invention, the gear motor 27 is driven while the rotor 21 is rotated in the direction of the arrow X as shown in FIG. 24
is caused to reciprocate between the center and the peripheral edge of the rotor 21, and the injection nozzles 24 and 23
High-pressure water of 90 to 100 kg/cm ² is jetted toward the rotor 21, and paint mist and the like adhering to the rotor 21 are successively wiped off over the entire surface of the rotor 21.

At the same time, the air nozzle 25, which is integrally attached to the upper part of the injection nozzle 24, is heated to 90°C.
High-pressure air that has been heated to a certain level is injected to wipe away moisture remaining in the vent hole 23 that has been cleaned by the injection nozzle 24, thereby drying it.

Therefore, according to the present invention, there is no need to install a cleaning device, a filter device, etc. in the path of the exhaust duct 11 to treat a large amount of exhaust gas, for example, about 5000 m ³ /min, as in the past, and the exhaust gas It is possible to reliably prevent paint mist and the like contained in the rotor from adhering to the rotor 21 and lowering the heat exchange efficiency, and the equipment cost and running cost of the entire air conditioning system can be significantly reduced.

At this time, the rotational speed of the rotor 21 is selected, for example, to a speed of 0.5 h/m ² that allows the spray nozzle 24 to clean the surface of the rotor 21 in 30 minutes per square meter.

Further, in the present invention, not only paint mist, organic solvents, etc. contained in the exhaust gas discharged from the exhaust duct 11, but also dust contained in the outside air sent into the air-conditioned room 12 are wiped off from the rotor 21. Therefore, heat exchange efficiency can be further improved than in conventional air conditioning equipment that simply uses a total heat exchanger.

Normally, the air in the coating booth 6 that is sucked into the mist processing chamber 8 of the supply coating booth 1 is brought into gas-liquid contact with the ventilate section 9 to cause the coating to coagulate and reduce its viscosity. A flocculant (commonly known as a killer agent) is mixed in to facilitate the recovery of paint components.

However, in this case, a part of the paint mist mixed with the flocculant is suctioned and discharged from the exhaust duct 11 and adheres to the rotor 21 of the total heat exchanger 20. There is a problem in that the surface of the rotor 21 is attacked by chemicals such as chemical soda contained in the flocculant and rust etc. occur, causing the rotor 21 to corrode.

In order to solve this problem, as shown in FIG. 1, it is possible to install a mist processing device 32 to collect the paint mist mixed with the flocculant on the upstream side of the total heat exchanger 20 in the exhaust duct 11. desirable.

As shown in FIG. 5, this mist processing device 32 includes a net conveyor or mesh screen 34, which serves as a mist collector, and an eliminator 35, which are arranged in series in a processing chamber 33, facing the exhaust flow path. The mesh screen 34 is formed in an endless shape and spans the sprockets 36 and 37.
It is configured to rotate continuously up and down at a predetermined speed. Further, the lower end side of the mesh screen 34 is immersed in water to form a water film on its surface. Further, below the mesh screen 34, the mesh screen 34 is
A scraper 38 is disposed in sliding contact along the width direction from one side of the mesh screen 34, and a spray nozzle 39 is disposed opposite to the other side of the mesh screen 34 and sprays high-pressure water along the width direction. .

Therefore, when the paint mist containing the flocculant is sent into the processing chamber 33 through the exhaust duct 11,
This is collected on the surface of the mesh screen 34, scraped off from both sides of the mesh screen 34 by the scraper 38, and simultaneously blown off by high pressure water from the injection nozzle 39, and drains into the drainage gutter 40 and 41 and is discharged.

Therefore, the mesh screen 34 is installed in the total heat exchanger 20 on the downstream side of the mist processing device 32.
Since the processing air from which the paint mist containing the flocculant has been removed is fed, it is reliably prevented that the flocculant mist will adhere to the rotor 21 of the total heat exchanger 20 and cause rust.

〔Effect of the invention〕

As described above, according to the present invention, heat exchange is performed between the outside air sent to the air conditioner that supplies clean air into the supply coating booth and the exhaust gas discharged from the exhaust duct of the supply coating booth. Since the rotor of the total heat exchanger is designed to be directly cleaned with high-pressure water, the large amount of exhaust gas discharged from the exhaust duct must be purified using cleaning equipment, filter equipment, etc., which requires high running costs. It is possible to reliably prevent a decrease in heat exchange efficiency of the rotor due to adhesion of paint mist, organic solvents, etc. in the exhaust air, and prevent dust contained in the outside air fed into the air conditioner from adhering to the rotor. This has the excellent effect of preventing a decrease in heat exchange efficiency. Therefore, it is possible to further improve the heat exchange efficiency and achieve energy savings compared to the conventional method, and it is also possible to significantly reduce the running cost of the entire air conditioning equipment.

[Brief explanation of drawings]

Figure 1 is a flow sheet diagram showing a supply painting booth and its air conditioning equipment according to the present invention, Figures 2 and 3
The figure shows a front perspective view and a rear perspective view of the total heat exchanger that constitutes the main part, Figure 4 is a partial sectional view of the total heat exchanger, and Figure 5 shows the mist treatment installed in the exhaust duct. FIG. 2 is a cross-sectional view showing an example of the device. Explanation of symbols, 1... Supply painting booth, 2...
Air conditioner, 4...Air supply room, 6...Painting booth, 7
... Floor surface, 8 ... Mist processing chamber, 9 ... Ventilation section, 11 ... Exhaust duct, 17 ... Cooler,
19... Heater, 20... Total heat exchanger, 21...
Rotor, 23...Vent hole, 24...Injection nozzle,
26...Feed screw rod, 27...Gear motor, F ₁
...Outside air flow path, F ₂ ...Exhaust air flow path.

Claims (1)

[Claims] 1. Clean air supplied from an air conditioner that controls the temperature of the outside air is forced into the paint booth, and this is sucked into the floor together with the paint mist and evaporated organic solvent inside the paint booth to separate the paint mist, etc. through gas-liquid contact. After removal, in the air conditioning equipment of the paint booth where the supply air is discharged to the outside from the exhaust duct,
A rotor of a total heat exchanger that exchanges heat between the outside air sent into the air conditioner and the exhaust gas discharged from the exhaust duct is arranged to rotate while crossing the flow path of the outside air and the exhaust gas. At the same time, an injection nozzle is disposed opposite to one side of the rotating rotor and injects high-pressure water into the ventilation hole of the rotor, and the injection nozzle reciprocates between the center and the peripheral edge of the rotor. This is an air conditioning system for a supply painting booth that is characterized by the following features: