JPH0634953B2 - Air-conditioning equipment for painting boots with air supply - Google Patents

Description

The present invention relates to an air conditioning facility for supplying conditioned air into a relatively large air-conditioned paint booth for painting automobiles and the like.

[Conventional technology]

A large-scale air-supply coating booth for coating automobiles heats or cools the outside air introduced into the air conditioner to adjust the temperature of the conditioned air to about 25 ° C., for example, the width of the coating booth is 6 m or 50 m.
Since it supplies about 7,200 m ³ / min per unit, a very large capacity of the heater and cooler installed in the air conditioner is required, which increases the equipment cost and running cost of the air conditioner. In particular, in summer and winter, when the temperature difference between the outside air and the conditioned air is large, there is a problem that the running cost is significantly higher than in other seasons.

For this reason, conventional air conditioning equipment is equipped with a heat exchanger that exchanges heat between the outside air introduced into the air conditioner and the exhaust gas discharged from the coating booth, and the heater and cooler of the air conditioner are required. Attempts have been made to reduce the amount of heat and save energy (JP-A-55-3888, JP-A-57-16).
5036, JP-A-62-66033).

Then, in order to enhance this energy saving effect, Japanese Patent Laid-Open No.
As described in JP-A-7-165063 and JP-A-62-66033, the air supply side and the air discharge side of a rotor (rotary heat storage body) made of a honeycomb-shaped hygroscopic porous material are introduced into an air conditioner. The rotary total heat that is installed in the external air flow path and the exhaust air flow path exhausted from the coating booth, respectively, and also recovers sensible heat and latent heat by rotation of the rotor to recover total heat (enthalpy). The use of exchangers is said to be a good idea.

FIG. 3 is a front view showing the rotary heat exchanger, and FIG. 4 is a flow sheet diagram showing the air conditioning equipment of the air-supply coating booth using the heat exchanger.

An air supply coating booth 1 for car coating is provided with an air supply chamber 4 to which conditioned air is supplied from an air conditioner 2 by an air supply fan 3.
A coating chamber 6 in which the conditioned air in the air supply chamber 4 is pushed through the filter 5 at a predetermined wind speed, and an exhaust treatment chamber for sucking air containing paint mist, evaporated organic solvent, etc. generated in the coating chamber 6 under the floor. An air exhaust duct 10 having an exhaust fan 9 in which the air that is sucked into the exhaust processing chamber 7 is separated and removed by a gas-liquid contact mechanism 8 to remove paint mist and the like.
It is designed to be discharged to the outside through.

The air conditioner 2 has an air supply gallery 12 inside the air conditioning room 11.
Primary filter 1 for removing dust in the outside air introduced from the
3 and the secondary filter 14 and these filters 13, 1
Humidifier 1 for controlling the humidity and temperature of the outside air purified through 4.
5, the cooler 16 and the heater 17 are connected in series.

Then, the rotary total heat exchanger HE is installed so that the air supply side 18a and the exhaust side 18b of the rotor 18 are interposed in the air conditioning chamber 11 and the exhaust duct 10 of the air conditioner 2, respectively. A rotor 18, which is rotated at a low speed so as to traverse the flow path F _{1 of the} outside air introduced into the air-conditioning chamber 11 and the flow path F _{2 of the} exhaust gas discharged from the coating booth 1, for example, on the exhaust duct 10 side in winter. The heat in the exhaust gas is supplied, and the heat is radiated on the air conditioning chamber 11 side to heat and humidify the outside air.

By the way, the total heat exchanger HE is provided with a purge sector 19 that presses the gas inside the rotor 18 to the exhaust side 18b when the rotor 18 rotates to bring it from the exhaust side 18b to the air supply side 18a.

That is, the rotor 18 made of a porous material is filled with a gas containing an evaporated organic solvent when the rotor 18 passes through the exhaust duct 10, and the gas is conditioned by the rotation of the rotor 18. When brought into the room 11, the evaporated organic solvent or the like is mixed into the outside air introduced into the air conditioning room 11 and the air conditioning air supplied from the air conditioner 2 to the coating booth 1 is contaminated. For this reason, the purge sector 19 is provided along the boundary part where the rotor 18 moves from the exhaust side 18b to the air supply side 18a by its rotation, and the gas in the rotor 18 which is to be brought into the air supply side 18a from the exhaust side 18b is exhausted. Purge air that flows from the air supply side 18a in the air conditioning chamber 11 to the exhaust side 18b in the exhaust duct 10 at a supply pressure (+60 mmAg) of the outside air that is greater than the exhaust pressure (+20 mmAg) of the exhaust gas discharged through the duct 10 ( It is configured to be squeezed out to the exhaust side 18b by the outside air).

[Problems to be solved by the invention]

However, according to the research conducted by the present inventors, in the winter when the temperature difference between the outside air and the exhaust gas is large, the rotor 18 cooled by the cold outside air introduced into the air conditioning chamber 11 causes the air conditioning chamber 11 to be cooled.
From the air supply side 18a inside to the exhaust side 18b inside the exhaust duct 10
About 20 ° C passing through the exhaust side 18b when shifting to
It was found that the water and the low boiling point evaporated organic solvent contained in the warm exhaust gas before and after the condensation condense to cause dew condensation inside the rotor 18.

Further, unlike the gas, the organic solvent component condensed in the rotor 18 cannot be pressed out to the exhaust side 18b by the purge air passing through the purge sector 19, so that the exhaust side 1
8b to the air supply side 18a as it is, and the air conditioning room 1
The result is that it evaporates in 1 and pollutes the conditioned air supplied from the air conditioner 2 to the coating booth 1. The amount of the organic solvent component brought into the air supply side 18a in the dew condensation state reached about 1 ppm, which is 1/10 of the agricultural degree in exhaust gas of 10 ppm in the exhaust duct 10.

[Means for solving problems]

Therefore, an object of the present invention is to reliably prevent the harmful effect that the organic solvent component contained in the exhaust gas discharged from the coating booth is condensed in the rotor of the rotary heat exchanger and brought into the air conditioner. .

In order to achieve this object, the present invention provides a flow path for outside air introduced into an air conditioner for supplying conditioned air to a coating booth on the air supply side and the exhaust side of a rotor made of a porous material, and coating. In the rotary heat exchangers that are respectively interposed in the flow paths of the exhaust gas discharged from the booth, the rotor is rotated from the exhaust side to the supply side, and the rotation side heat exchanger is transferred from the supply side to the discharge side. In an air-conditioning equipment of an air supply coating booth provided with a purge sector for circulating barge air, a hot air blowing duct that blows high temperature purge air from the upstream side of the outside air toward the air supply side of the rotor facing the purge sector. Is provided.

[Action]

According to the present invention, the high-temperature purging air blown out from the hot air blowing duct becomes purge air mixed with the outside air by the supply pressure of the outside air introduced into the air conditioner, passes through the purge sector, and passes through the rotor. It flows from the air supply side to the exhaust side. As a result, the organic solvent component that has condensed on the exhaust side of the rotor installed in the flow path of the exhaust gas discharged from the coating booth is supplied to the rotor installed in the flow path of the outside air introduced into the air conditioner. Immediately before shifting to the air side, it is evaporated in the rotor and is forced out to the exhaust side. Therefore, the adverse effect that the conditioned air supplied from the air conditioner to the coating booth is contaminated by the organic solvent component contained in the exhaust gas discharged from the inside of the coating booth can be reliably prevented.

〔Example〕

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a flow sheet diagram schematically showing an example of the air conditioning equipment according to the present invention, and FIG. 2 is a partially enlarged view showing a main part thereof. It should be noted that parts common to FIGS. 3 and 4 will be described with reference to FIG.

In this example, as in FIGS. 3 and 4, the rotary total heat exchanger HE introduces the intake side 18a and the exhaust side 18b of the rotor 18 made of a porous material into the air conditioner 2. The flow path F ₁ for the outside air and the flow path F ₂ for the exhaust gas discharged from the coating booth 1 are installed so as to be interposed respectively.
Further, the heat exchanger HE is provided with a purge sector 19 that allows purge air to flow from the air supply side 18a to the air exhaust side 18b along the boundary portion where the rotor 18 rotates to move from the air exhaust side 18b to the air supply side 18a. Has been.

Then, unlike the conventional example shown in FIG. 3, hot purge air is blown from the upstream side of the outside air introduced into the air conditioner 2 toward the air supply side 18a of the rotor 18, facing the purge sector 19. A hot air blowing duct 20 is provided.

The hot-air outlet duct 20 has a hot-air outlet 21 opened along the longitudinal direction of the purge sector 19 facing each other across the rotor 18, and a U-shaped cover 22 that surrounds the hot-air outlet 21 from the left and right sides of the rotor 18. It is provided so as to face the surface of the object at a constant interval.

In the figure, reference numeral 23 denotes a paint drying furnace that heats the interior of the furnace to a high temperature atmosphere of 170 ° C. to 180 ° C. to bake and dry the automobile coating, and is a vehicle body 24 that is heated in the drying oven 23. Exhaust gas containing harmful foul-smelling substances such as organic solvents and paint resins evaporated from the coating film is exhausted by an exhaust fan 26 installed in an exhaust duct 25 to be a catalytic combustion type or a direct combustion type deodorizing device 2.
7 to burn and decompose harmful odorous substances in exhaust gas,
It is designed to produce harmless and odorless deodorant gas and then release it to the outside.

The exhaust gas after passing through the deodorizing device 27 in this way becomes a high-temperature gas of 200 ° C. to 300 ° C. or higher due to combustion decomposition of harmful malodorous components, and this gas passes through the pipe 28 connected to the exhaust duct 25. The hot air blowing duct 20 is configured to be supplied as purge air.

Therefore, the total amount of purge air that flows from the air supply side 18a of the rotor 18 through the purge sector 19 to the exhaust side 18b by the air supply pressure of the outside air introduced into the air conditioner 2 is
For example, in the case of 50 Nm ³ / min, the outside air of 5 ° C. introduced into the air conditioner 2 is 35 Nm ³ / min, and the purge air of 300 ° C. blown out from the hot air outlet 21 of the hot air outlet duct 20 is: Mixing 15 Nm ³ / min gives a purge air of 96 ° C.

Then, this 96 ° C. purge air is supplied to the purge sector 19
Through the inside of the rotor 18 from the air supply side 18a to the exhaust side 18b
When it circulates, the organic solvent component that has condensed in the rotor 18 on the exhaust side 18b is evaporated by the high heat of the purge air, and is extruded together with the purge air to the exhaust side 18b in the exhaust duct 10 so that it is substantially completely removed from the inside of the rotor 18. Will be removed.

Therefore, the harmful effect that the conditioned air supplied from the air conditioner 2 to the coating booth 1 is contaminated by the organic solvent component contained in the exhaust gas discharged from the inside of the coating booth 1 is reliably prevented.

In addition, the air supply side 1 of the rotor 18 installed in the air conditioner 2
Since 8a is heated by the high temperature purge air, the effect of heating the outside air by the total heat exchanger HE is enhanced.

Further, if the exhaust gas discharged from the paint drying furnace 23 is used as the purging air blown out from the hot air blowing duct 20 as in the embodiment, a special heat source for heating the purging air becomes unnecessary, which is unnecessary. There is no running cost.

Further, if the exhaust gas discharged from the paint drying furnace 23 is passed through the deodorizing device 27 and the clean deodorizing gas generated by burning and decomposing the harmful malodorous substances in the exhaust gas is sent to the hot air blowing duct 20, the hot air blowing will be performed. There is no fear that the conditioned air is contaminated by the purge air blown out from the duct 20.

The rotary heat exchanger according to the present invention is not limited to the total heat exchanger that also recovers latent heat as well as sensible heat, and may be a heat exchanger that recovers only sensible heat.

〔The invention's effect〕

As described above, according to the present invention, dew condensation occurs on the exhaust side of the rotor of the rotary heat exchanger during the winter when the temperature difference between the outside air introduced into the air conditioner and the exhaust gas discharged from the coating booth is large. The organic solvent component is contained in the exhaust gas discharged from the coating booth because it is evaporated by the high temperature purge air immediately before it shifts from the exhaust side to the supply side by the rotation of the rotor and is forced out to the exhaust side together with the purge air. There is an excellent effect that the harmful effect that the organic solvent component is brought into the air conditioner through the rotor of the rotary heat exchanger can be surely prevented.

Further, there is also an effect that the air supply side of the rotor interposed in the flow path of the outside air introduced into the air conditioner is heated by the high-temperature purge air to enhance the effect of heating the outside air.

[Brief description of drawings]

FIG. 1 is a flow sheet diagram schematically showing an example of the air conditioning equipment according to the present invention, FIG. 2 is a partially enlarged view showing a main part thereof, FIG. 3 is a front view showing a rotary heat exchanger, and FIG. [Fig. 6] is a flow sheet diagram showing a conventional air-conditioning equipment of a paint booth with air supply. REFERENCE NUMERALS 1 ...... paint booth, 2 ...... air conditioner, 10 ...... exhaust duct, 11 ...... air conditioning room, F 1 _...... outside air flow path, F 2 _...... exhaust flow path, HE ...... rotary Heat exchanger, 18 ... rotor,
18a ... rotor air supply side, 18b ... rotor exhaust side, 19 ... purge sector, 20 ... hot air blowing duct,
23 ... Paint drying oven.

Claims (2)

[Claims] 1. A flow path for outside air introduced into an air conditioner for supplying conditioned air to a coating booth on the air supply side and exhaust side of a rotor made of a porous material, and exhaust gas discharged from the coating booth. In the rotary heat exchangers respectively interposed in the flow paths of the, there is a purge sector for flowing the barge air from the air supply side to the air exhaust side along the boundary portion where the rotor moves from the air exhaust side to the air supply side due to the rotation thereof. In the provided air-conditioning equipment of the coating booth, a hot air blowing duct is provided facing the purge sector to blow hot purging air from the upstream side of the outside air toward the feeding side of the rotor. Air conditioning equipment characterized by. 2. The air conditioning equipment according to claim 1, wherein the purging air blown out from the hot air blowing duct is a high-temperature exhaust gas fed from a paint drying furnace.