JPH067635A - Organic solvent removing device for coating booth with dehumidifying and humidifying functions - Google Patents

Abstract

PURPOSE:To economically obtain the appropriate atmosphere for coating work in a coating booth by dehumidifying or humidifying the purified gas having been remove organic solvent from waste gas in the coating booth to obtain and returning it to the coating booth again. CONSTITUTION:To an exhaust pipe 11 connected to the exhaust port of a coating booth 1 in which coating is performed by using a coating material contg. organic solvent, a concentrating deodorizing device 13 for removing organic solvent in waste gas through an exhaust filter 12 is installed. On the downstream side of the concentrating/deodorizing device 13, a dehumidifying/humidifying device 5 for dehumidifying or humidifying the purified gas from which organic solvent has been separated is installed. The purified gas from the dehumidifying/ humidifying device is supplied to an intake pipe 10 connected to the intake port of the coating booth 1 through a fan 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing an organic solvent in exhaust gas discharged from a coating chamber for coating a paint containing an organic solvent and for dehumidifying or heating the coating chamber.

[0002]

2. Description of the Related Art In order to remove the organic solvent contained in the exhaust gas discharged from a coating chamber for coating with a coating containing an organic solvent, and to maintain the temperature and humidity conditions in the coating chamber suitable for coating work, Conventionally, as shown in FIG. 3, a concentrated deodorizing device 13 for removing an organic solvent is provided on the exhaust side of the coating chamber 1, and also the coating chamber 1
A dehumidifying / warming device 5 capable of switching between dehumidifying and heating is separately provided on the air supply side.

That is, the exhaust gas containing the organic solvent discharged from the coating chamber 1 is exhausted through the exhaust pipe 11 to the exhaust filter 12
After removing the paint mist through the exhaust pipe, the concentrated deodorizing device 13 removes the organic solvent in the exhaust gas, and the purified gas is supplied to the air pipe 1
4 through the exhaust fan 15 and the exhaust pipe 16 into the atmosphere.

In the concentrating deodorizing device 13, the outside air 17 for regeneration is heated by a regeneration heater 18 to produce a regenerated hot air 19, which is passed to separate the organic solvent and regenerate. Since this regenerated hot air 19 has a much smaller air volume than the exhaust gas containing the organic solvent, the exhaust gas 20 containing the organic solvent concentrated in the concentration deodorizing device 13 is passed through the regeneration fan 21 to the organic solvent decomposing device. At 22, it is possible to easily remove the organic solvent with a small amount of energy, and the purified gas 23 thus purified is discharged to the outside air.

However, when the air in the coating chamber 1 is exhausted by the above-mentioned apparatus, it is necessary to introduce the outside air into the coating chamber 1. In this case, the temperature and humidity conditions in the coating chamber are appropriately maintained. In order to remove the dust from the introduced outside air 2 for air supply by the air supply filter 3, it is passed through the dehumidification / heating device 5 capable of switching between dehumidification and heating via the air supply pipe 4,
When dehumidification is required, cold water is passed through the device to cool and dehumidify it, and when warming is required, warm water is heated to the device and the air is supplied to the coating chamber 1 through the air supply fan 9 and the air supply pipe 10. I care.

The dehumidifying / warming device 5 requires cold / hot water 7 as its cold / heat source, which is provided separately.
Cooling or heating the circulating water with the hot water generator 6
It is circulated and used by the hot water pump 8. The case where the dehumidifying device is of the cooling type has been described, but the same applies to the case of the adsorption type dehumidifying device using an adsorbent.

[0007]

[Problems to be Solved by the Invention]
Since it is required to lower the concentration of the organic solvent in the coating chamber as much as possible, the air volume becomes large. Along with this, the supply air volume also becomes large, so a dehumidifying / heating device with a very large capacity is also required.In reality, the removal of the organic solvent in the exhaust gas and the temperature / humidity in the coating chamber are required. It was almost impossible to install equipment that could make

Further, even if a large-capacity device is installed, it takes a long time to maintain the atmosphere in the coating chamber under constant conditions, which is unavoidably uneconomical. Therefore, efficiently remove the organic solvent in the exhaust gas,
Further, it is an object of the present invention to provide a device capable of dehumidifying or heating the air in the coating chamber to maintain an atmosphere suitable for coating work in the coating chamber with a small capacity dehumidifying / heating device. Is.

[0009]

The organic solvent removing device for a coating chamber with dehumidifying and heating functions according to the present invention has been conventionally installed separately on the exhaust side and the air supplying side of the coating chamber. Arranging the device 13, the dehumidifying / warming device 5 or the cooling type dehumidifying device 24 and the heating device 29 as an integrated facility in one circulating piping system is a means for solving the above problems. It is a thing.

That is, the first aspect of the present invention is that the exhaust pipe 11 connected to the exhaust port of the coating chamber 1 for performing the coating using the coating material containing the organic solvent is connected to the exhaust pipe 12 through the exhaust filter 12, The concentrated deodorizing device 13 for removing the organic solvent is provided, and the dehumidifying / heating device 5 for dehumidifying or heating the purified gas from which the organic solvent has been removed is provided on the downstream side of the concentrated deodorizing device 13. Is a dehumidifying and heating organic solvent removing device for a coating chamber, in which the purified gas from is supplied to the air supply pipe 10 connected to the air supply port of the coating chamber 1 through a fan 9.

A second aspect of the present invention is to provide a cooling type dehumidifying device 24 via an exhaust filter 12 in an exhaust pipe 11 connected to an exhaust port of a coating chamber 1 for coating with a coating material containing an organic solvent. At the same time, a concentration deodorizing device 13 for removing the organic solvent is provided on the downstream side thereof, and a heating device 29 for heating the purified gas from which the organic solvent has been removed is provided on the downstream side of the concentration deodorizing device. Is an organic solvent removing device with a dehumidifying and heating function for a coating chamber, in which the purified gas is supplied to a gas supply pipe 10 connected to a gas supply port of the coating chamber 1 via a fan 9.

[0012]

[Function] Even though it is a purified gas in which the organic solvent in the exhaust gas has been removed by the concentration deodorizing device, there is no organic solvent at all,
Under appropriate operating conditions, the concentration is several PPM, and even if the purified gas is supplied to the coating room again, as long as the exhaust air volume is sufficient, the inside of the coating room will not cause any problems for workers. Since the atmosphere has a solvent concentration, continuous painting work is possible.

Moreover, in the concentration deodorizing device, the moisture content is reduced and is not humidified even if it is not reduced, so that the dehumidified purified gas can be supplied to the coating chamber again.
Also, in terms of temperature conditions, the temperature rise of exhaust gas in the concentration deodorizing device is very small, so it does not affect the load of the cooling and dehumidifying device so much, and conversely, the effect of reducing the load of the heating device during heating. There is.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention,
FIG. 2 shows a second embodiment of the present invention. In each drawing, the same parts as those in FIG. 3 showing the conventional example are designated by the same reference numerals and the description thereof will be omitted.

First, in the first embodiment, as shown in FIG. 1, an exhaust filter 1 is attached to an exhaust pipe 11 connected to an exhaust port of a coating chamber 1 for coating with a paint containing an organic solvent.
2 is provided with a concentration deodorizing device 13 for removing the organic solvent in the exhaust gas, and a dehumidifying / heating device 5 for dehumidifying or heating the purified gas from which the organic solvent has been removed is provided on the downstream side of the concentration deodorizing device 13. A dehumidifying and heating function for a coating chamber, which is provided and supplies purified gas from the dehumidifying / warming device to a gas supply pipe 10 connected to a gas supply port of the coating chamber 1 through a fan 9. It is a device for removing organic solvent.

In the first embodiment, the concentration deodorizing device 1 is used.
In step 3, the organic solvent is removed, and the purified gas that has been purified is not discharged to the outdoors, but is guided by the air supply pipe 14 and passed through the dehumidifying / warming device 5. When dehumidifying is necessary, cold water is supplied to the device. When the heating is required, the apparatus is heated with hot water, and the air is supplied to the coating chamber 1 through the air supply fan 9 and the air supply pipe 10.

Now, a concrete example in which the apparatus of the first embodiment is installed and operated in a bridge steel frame coating room will be described below together with a comparative example. The main conditions of the coating room are as follows.

The case where the apparatus of the prior art shown in FIG. 3 is installed and operated in the coating chamber and the case of the first embodiment shown in FIG.
Compare with the case where the device shown in (1) is installed and operated. Exhaust treatment equipment such as the concentration deodorizing device 13 has the same capacity in both devices, but the capacity of the dehumidifying / warming device 5 is significantly different from the conventional device and the device of the first embodiment. It becomes a thing. That is, comparing the capacities of the dehumidifying / heating devices, the heat load and the water load of the coating chamber are the same in both devices, but in the device of the prior art, the exhaust gas of the concentration deodorizing device 13 is exhausted.
In order to discharge all 700Nm ³ / MIN, the same amount as this exhaust
The outside air of 700 Nm ³ / MIN must be dehumidified or heated by the dehumidifying / heating device to supply air. In contrast,
In the case of the device of the first embodiment, the purified gas discharged from the concentration deodorizing device 13 may be dehumidified or heated, so that the load corresponding to the outside air load can be greatly reduced.

At the time of dehumidification operation, the enthalpy of the outside air is i _OA1 = 23.0 kcal / kg 'in the conventional device.
So, the enthalpy of the air in the painting room is ip = 20.4Kc
al / kg ', the external air load is q ₁ = (23.0−2
0.4) × 1.29 × 700 × 60 = 140,868 kcal / HR, but in the device of the first embodiment, the temperature of the exhaust gas from the coating chamber rises only about 1 ° C. in the deodorizing device, and the water content is the same. Or, it decreases by about 1g / Nm ^{3 in} absolute humidity.

Even if the worse condition is used to make room for the equipment, that is, the temperature rises by 1 ° C. and the moisture content is the same as the calculation condition, the enthalpy at the entrance to the dehumidifying / heating coil 5 is increased. Is i _OA2 = 20.6kcal / kg '(31 ℃, 21.6g / kg')
And the outside air load is q ₂ = (20.6 −20.4) × 1.29 × 7
Since 00 × 60 = 10,836 kcal / HR, the external air load is 1/10 or less that of the conventional device.

During the heating operation, the outside air load of the prior art device is also q ₃ = 0.31 × 10 × 700 × 60 = 130,20
Although it becomes 0 kcal / HR, in the device of the first embodiment, as described above,
On the other hand, the temperature rises by about 1 ° C in the concentrating deodorizer, so heat is supplied instead of a load.
Even if the temperature rise of ℃ is ignored, the capacity can be reduced by about 130,000 kcal / HR.

In the above description, the dehumidifying device is described as a cooling type, but the same effect can be obtained with an adsorption type dehumidifying device using an adsorbent.

Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, as shown in FIG. 2, an exhaust filter 12 is attached to an exhaust pipe 11 connected to an exhaust port of a coating chamber 1 in which a coating material containing an organic solvent is used for coating.
A cooling type dehumidifying device 24 is provided through the same, a concentration deodorizing device 13 for removing an organic solvent is provided on the downstream side thereof, and a heating device for heating the purified gas from which the organic solvent has been removed is provided on the downstream side of the concentration deodorizing device. Dehumidification and heating for a coating chamber in which the purified gas from the heating device 29 is provided to the air supply pipe 10 connected to the air supply port of the coating chamber 1 through the fan 9. It is an organic solvent removal device with a function.

In the above second embodiment, when the dehumidifying means is a cooling system, dehumidification can be performed more efficiently and deodorizing efficiency can be improved, and the paint mist is removed by the exhaust filter 12. After that, first, the exhaust gas that has been cooled and dehumidified is first sent to the cooling type dehumidifying device 24 and sent to the concentrating deodorizing device 13 through the air supply pipe 28, so that an effect of increasing the adsorption efficiency can be obtained in a low temperature state, and at the same time, the concentrating deodorizing device 1 can be obtained.
The water adsorption effect in 3 can be increased, and the dehumidification effect can be improved.

This is because a commonly used concentration deodorizing device is
This is because activated carbon or zeolite is used, and the lower the treatment air temperature, the higher the adsorption effect of the organic solvent and water. In this case, when heating is necessary, the discharged purified gas is supplied to the heating device 29 by the air supply pipe 14 to be heated, and is supplied to the coating chamber 1 by the air supply pipe 10 via the air supply fan 9.

As the cooling source of the cooling type dehumidifying device 24, the cold water generator 25 cools the cold water 26 and the cold water pump 27 is used.
Circulate and use. The heating source of the heating device 29 is
The hot water 31 is heated by the hot water generator 30, and the hot water pump 3
Circulate at 2 and use. In addition, this hot water generating means,
Other than this embodiment, it is also possible to perform heat exchange of electricity, steam or combustion exhaust gas, and it is also possible to use a heat pump type chiller / heater that generates chilled / hot water.

[0027]

As described above, according to the organic solvent removing apparatus for a coating chamber with the dehumidifying and heating function of the present invention, the equipment capacity of the dehumidifying and heating apparatus can be greatly reduced. The cost can be reduced. That is, dehumidification of the coating room
Prior art devices used for warming typically have
Since about 5% was the outside air load, in the device of the present invention,
The dehumidifier has a dehumidifying capacity of about 70% and a heating capacity of 75%.
It is possible to reduce the capacity in the order of% over prior art devices.

Further, since the atmosphere in the coating chamber can be efficiently and economically set to a predetermined condition, the quality of coating can be improved and the control of the coating process can be stabilized.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a first embodiment according to the present invention.

FIG. 2 is a circuit diagram of a second embodiment according to the present invention.

FIG. 3 is a circuit diagram of an embodiment according to the related art.

[Explanation of symbols]

 1 Painting Room 5 Dehumidification / Warming Device 6 Cold / Hot Water Generator 8 Cold / Hot Water Pump 9 Air Supply Fan 12 Exhaust Filter 13 Concentration Deodorizer 18 Regeneration Heater 21 Regeneration Fan 22 Organic Solvent Decomposition Device 24 Cooling Dehumidification Device 25 Cold water generator 27 Cold water pump 29 Heating device 30 Hot water generator 32 Hot water pump

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location F24F 3/16 6803-3L

Claims (2)

[Claims] 1. Concentrated deodorization for removing an organic solvent in exhaust gas through an exhaust filter 12 to an exhaust pipe 11 connected to an exhaust port of a coating chamber 1 for applying a coating containing an organic solvent. A device 13 is provided, and a dehumidifying / warming device 5 for dehumidifying or heating the purified gas from which the organic solvent has been removed is provided on the downstream side of the concentration / deodorization device 13, and the purified gas from the dehumidifying / heating device is blown by a fan. A dehumidifying and heating organic solvent removing device for a coating chamber, which supplies air to a gas supply pipe 10 connected to an air supply port of the coating chamber 1 via 9. 2. A cooling type dehumidifying device 24 is provided through an exhaust filter 12 in an exhaust pipe 11 connected to an exhaust port of a coating chamber 1 for performing coating using a paint containing an organic solvent, and is provided on the downstream side thereof. Concentrating deodorizer 1 for removing organic solvent
3 is provided, a heating device 29 for heating the purified gas from which the organic solvent has been removed is provided on the downstream side of the concentration deodorizing device, and the purified gas from the heating device 29 is supplied to the coating chamber via the fan 9. An organic solvent removing device with a dehumidifying and heating function for a coating room, which is configured to supply air to an air supply pipe 10 connected to a first air supply port.