JPS6129730Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a supply and exhaust system for an electrodeposition coating line, and more particularly to a device for thermally decomposing and exhausting solvent gas generated in an electrodeposition coating booth in an electrodeposition coating line.

Electrodeposition painting is a method in which when a water-based paint is dispersed or dissolved in water, the paint resin is electrophoresed using the fact that it is positively or negatively charged, and the paint is deposited on the object to be coated. Because the resulting coating film has excellent corrosion resistance, it is widely used for coating various industrial products such as automobile bodies and parts, electric refrigerators, and electric washing machines.

As an apparatus for performing such electrodeposition coating, there is a conventional apparatus shown in FIG. That is,
In the electrodeposition coating booth 1, there is an electrodeposition paint bathtub 2, an overflow tank 3 adjacent to the bathtub, a water spray device 4,
5, 6, drain pans 7, 8, 9 below, water tanks 10, 11, 12, washing tank 13, water spray device 14, overhead conveyor 15, etc.
In this electrodeposition coating booth 1, a workpiece 17 suspended from a hanger 16 and conveyed by an overhead conveyor 15 is immersed in a paint bath stored in an electrodeposition paint bath 2, and is immersed as a counter electrode. A voltage is applied between the anode or cathode (not shown), and the liquid is drained in the overflow tank 3. They are washed by spraying overwater from the device 18, then immersed in the washing tank 13 for washing, and then sprayed with fresh water by the water spraying device 14 for washing, and then transported to the baking drying oven, which is the next step. be done. In this case, since the electrodeposition coating booth 1 is filled with air containing the solvent in the paint evaporated from the electrodeposition paint bath 2 and the solvent volatilized during the water washing process, the discharge device, e.g. It is necessary to discharge it using the fan 21.

For this reason, such solvent-containing air contains malodorous components and cannot be released directly into the atmosphere for environmental protection. Therefore, deodorizing devices such as combustion furnaces and activated carbon adsorption devices are used. I had no choice but to do it. However, in this method, it is necessary to separately install a deodorizing device, which not only increases the cost of the equipment, but also requires auxiliary fuel if a combustion furnace is used, and adsorbent such as activated carbon if an adsorption device is used. There was a problem in that the operating costs were high because of the high cost.

The present invention was developed by focusing on these conventional problems, and includes an electrodeposition coating booth, a drying oven following the booth, an exhaust gas combustor of the drying oven,
A paint exhaust duct that connects the combustor and the electrodeposition coating booth, a drying furnace exhaust duct that connects the combustor and the drying furnace, and a combustion gas supply duct that connects the combustor and the drying furnace. The purpose of this project is to solve the above-mentioned problems by providing an air supply and exhaust system for an electrodeposition coating line.

Hereinafter, the present invention will be explained based on the drawings. Second
The figure shows a first embodiment of the present invention.

First, to explain the configuration, the electrodeposition coating booth 1 includes an electrodeposition paint bathtub 2, an overflow tank 3 adjacent to the bathtub, water spray devices 4, 5, 6, drain pans 7, 8, 9 at the bottom, and a water tank. 10,11,1
2, a washing tank 13, a water spray device 14, an overhead conveyor 15, etc. are built in, and exhaust ducts 19, 20 and a fan 21 are connected to the top. On the other hand, the drying oven 22 includes a setting zone 23, a preheating zone 24, and a heating zone 2.
5, and an overhead conveyor 15 is attached.

The fan 21 of the painting booth 1 is the fan 27
via an exhaust duct 26 to a combustor 28, which is connected to the top of the drying oven 22 by an exhaust duct 29 of the first drying oven. This combustor 28 includes a filter 30 and a fan 31.
and is connected to the drying oven 22 by a first hot air supply duct 32. The exhaust duct 26 is further connected to a second combustor 34 via an exhaust duct 26a and a fan 33, and the exhaust duct 35 of the second drying furnace connected to the combustor 34 is connected to the fan 36 and a first heat exchanger. combustor 34 via the vessel 37
is connected to. The exhaust duct 38 of the third drying oven connected to the drying oven 22 is connected to the heating drying duct 38 again by a second hot air supply duct 41 via a fan 39 and a second heat exchanger 40. On the other hand, the combustion gas in the second combustor 34 is
It is connected to a third hot air supply duct 42 via second heat exchangers 37 and 40, and is discharged outside the system via a fan 43.

Next, the effect will be explained. In the electrodeposition coating booth 1, a workpiece 17 suspended from a hanger 16 and conveyed by an overhead conveyor 15 is immersed in a paint bath solution stored in an electrodeposition paint bath 2 and electroplated in a conventional manner. After the coating is applied and the liquid is drained, the ultrafiltration device 1 is sprayed by water spray devices 4, 5, and 6.
8 is sprayed with water for washing, then immersed in a washing tank 13 for washing, further sprayed with fresh water by a water spray device 14 for washing, and then transported to a drying oven 22.

The object to be coated 17 transported to the drying oven 22 is first subjected to processes such as draining and drying in a setting zone 23, then preheated to a predetermined temperature in a preheat zone 24, and then transferred to a heating zone 2.
In step 5, the coating film is baked and cured, and then transported to the next step. In this electrodeposition heating and drying oven 22, odorous components evaporate from the coating film of the object 17 to be coated, and as they gradually accumulate and their concentration increases, it is necessary to discharge them.

Thus, the air containing odor components that evaporates in the electrodeposition coating booth 1 is exhausted from the top of the booth 1 through the exhaust ducts 19 and 20 through the fan 21, and is sent through the exhaust duct 26 to the first combustor 28. Here, it is used as combustion air for the exhaust gas containing odor components from the heating zone 25 of the heating drying oven 22 supplied from the exhaust duct 29 of the first drying oven, and the odor components are removed by combustion of the flammable components. Decomposed. In this case, auxiliary fuel may be used if necessary. The combustion gas is circulated through the filter 30 and fan 31 to the heating zone 25 of the heating drying furnace 22 by the first hot air supply duct 32.
The heating zone 25 is maintained at a predetermined temperature. Further, a part of the odor component-containing air from the electrodeposition coating booth 1 is sent to the second combustor 34 via the fan 33 by the exhaust duct 26a. On the other hand, a part of the exhaust gas containing combustible components from the heating zone 25 of the heating drying furnace 22 is sent from the exhaust duct 35 of the second drying furnace to the first heat exchanger 37, where it is preheated. The odor components are decomposed by being sent to the second combustor 34 and burned by the odor component-containing air from the exhaust duct 26a. At this time as well, auxiliary fuel may be used if necessary. Further, the exhaust gas from the preheat zone 24 of the heating drying furnace 22 is discharged from the exhaust duct 38 of the third drying furnace, heated by the second heat exchanger 40, and then transferred to the second hot air supply duct 4.
1, it is circulated again to the preheat zone 24. On the other hand, the combustion gas in the second combustor 34 is generated after heating the exhaust gas in the first and second heat exchangers 37 and 40, respectively, and indirectly heating the preheat zone 24 by the third hot air supply duct 42. , and is discharged out of the system by the fan 43.

FIG. 3 shows a second embodiment of the present invention, in which an apparatus similar to the first embodiment is used, in which the amount of exhaust from the electrodeposition coating booth 1 is adjusted to the first and second combustors 2.
In this case, a part of the odor-containing air from the exhaust duct 26 is sent to the exhaust duct 29 of the first and second drying ovens via ducts 44 and 45, respectively. , 35. In this figure, the same reference numerals as in FIG. 2 represent the same members.

As described above, the supply and exhaust system for an electrodeposition coating line according to the present invention includes an electrodeposition coating booth, an electrodeposition heating and drying oven that follows the booth, a heating and drying exhaust gas combustor, and an electric coating between the combustor and the A painting exhaust duct that connects the coating booth, a drying furnace exhaust duct that connects the combustor and the electrodeposition heating drying furnace, and a combustion gas supply duct that connects the combustor and the drying furnace. Therefore, the odor-containing air that evaporates in the electrodeposition coating booth is used as combustion air in the combustor of the electrodeposition heating and drying furnace, where it is combusted or decomposed and supplied to the drying furnace. Therefore,
Since it is used as the heat source for the drying oven or the air for generating the heat source, it not only eliminates the need for combustion equipment and adsorption equipment for cleaning exhaust gas from electrocoated coatings, which have been used in the past, but also reduces equipment costs. It has the advantage of lower operating costs because it eliminates the need for fuel and adsorbents that have been used in purifiers.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a conventional electrodeposition coating booth, FIG. 2 is a schematic diagram showing a first embodiment of an air supply and exhaust system for an electrodeposition coating line according to the present invention, and FIG. It is a schematic diagram showing a second embodiment of the invention. 1...Electrodeposition coating booth, 2...Electrodeposition paint bathtub,
4, 5, 6, 14... Water spray device, 13... Water washing tank, 19, 20, 26, 26a, 44, 45...
Exhaust duct, 28, 34... Combustor, 29, 3
5, 38...Exhaust duct of drying oven, 17...Object to be coated, 32, 41, 42...Hot air supply duct.

Claims (1)

[Scope of utility model registration request] An electrodeposition coating booth, a drying oven following the booth, an exhaust gas combustor of the drying oven, a coating exhaust duct connecting the combustor and the electrodeposition coating booth, and the combustor and the drying oven. 1. A supply and exhaust system for an electrodeposition coating line, comprising: an exhaust duct for a drying furnace connected to the drying furnace; and a combustion gas supply duct for connecting the combustor and the drying furnace.