JPH09103628A - Method for recovering mist of organic solvent in washing bath for washing using the organic solvent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously recover the mist of an organic solvent to be discharged in the air by a method in which the discharged mist is brought up in a recovery tank passing through the liquid membrane of an organic solvent having the same chemical structure. SOLUTION: The mist of an organic solvent generated from a washing bath 30 is supplied between the storage part 2 of a recovery tank 4 and a porous plate 3 placed above the storage part 2 and brought up by a suction device 16. An organic solvent having the same chemical structure as the mist is made to flow down from the upper part of the porous plate 3 to make a liquid film on the porous plate 3, and the mist is passed through the film. In this way, the mist is dissolved by compatibility and made to fall to a storage part 9 to be recovered. Recovered liquid consisting of the recovered mist and the organic solvent is supplied again from the upper part of the porous plate 3 to contribute to the recovery of the mist. Besides, gas from which the mist is removed is absorbed in water to be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recovering mist of an organic solvent in a cleaning tank for cleaning electronic parts and the like using an organic solvent.

[0002]

2. Description of the Related Art Conventionally, in a cleaning tank for cleaning the above electronic parts and the like using an organic solvent, an organic solvent is removed from an inlet for inserting the electronic parts into the cleaning tank or an outlet for taking out the cleaned electronic parts. Mist dissipates into the atmosphere.

In the present invention, the mist contains gas. And, as described above, the mist dissipated in the atmosphere causes pollution and reduces the amount of the cleaning agent, and the cleaning agent is usually expensive and damages. Although illustration is omitted as a conventional method for collecting mist of an organic solvent, a cooling method is generally used, and it is adhered in a frosted manner to the outer surface of a flexible pipe through which a refrigerant is passed, and then heated by a heating device to be liquefied. However, since the cooling temperature is extremely low, a powerful refrigerator is required, and since cooling and heating are repeated, handling is troublesome. Further, since the apparatus is cooled and heated, the apparatus cannot be operated continuously, which is inefficient. Further, as another method, there is a method of using activated carbon for adsorption and recovery, but the problem of deterioration due to the use of activated carbon occurs and maintenance is troublesome. And in the same method, activated carbon is cooled and adsorbed,
After that, since this is heated and desorbed, continuous operation cannot be performed, which is inefficient.

[0004]

As described above, the object of the present invention is to provide a cleaning tank for cleaning with an organic solvent,
It is to effectively collect the mist of the organic solvent that diffuses into the atmosphere, and to prevent the pollution due to the emission of the organic solvent into the atmosphere. Moreover, the recovery method is not a troublesome method of repeating strong freezing and heating, and it is not a method that cannot be continuously operated, and there is no troublesome maintenance due to deterioration of activated carbon such as when using activated carbon, and the same as above. It is an object of the present invention to provide a method for recovering mist of an organic solvent in a cleaning tank using an organic solvent, which is not a method that cannot be continuously operated, but is a method that is completely easy to operate, and that can be continuously recovered and is highly efficient. .

[0005]

The present invention which achieves the above-mentioned object is described as follows. The mist of the organic solvent generated in a cleaning tank for cleaning with an organic solvent is
Between the perforated plate and the perforated plate of the recovery tank having a reservoir part for accumulating the same organic solvent as the organic solvent at the bottom, an inclined perforated plate above the reservoir, and a suction device at the top. The organic solvent having the same chemical structure as the supplied mist is allowed to flow down from the upper part of the perforated plate to form a liquid film of the organic solvent having the same chemical structure on the perforated plate. , The mist is passed through the liquid film, dissolved by the compatibility with the same chemical structure, the dissolved organic solvent is dropped into the reservoir of the recovery tank to be recovered, and the recovered mist is dissolved in the organic solvent Is further supplied from above the perforated plate for liquid film formation and circulated, while the gas from which the mist has been removed is absorbed and removed with water, a cleaning tank for cleaning with an organic solvent. Mist times of organic solvent in It is a method. The hydrophilic portion is derived from water in the air or an object to be cleaned.

[0006]

According to the present invention, as described above, the mist of the organic solvent generated from the cleaning tank is stored in the collecting tank having the suction device at the upper portion thereof and the storage portion for storing the same organic solvent as the organic solvent and the upper portion thereof. It is supplied between the perforated plates and raised by the suction device. And in this case, from the upper part of the perforated plate, an organic solvent having the same chemical structure as that of the supplied mist is flowed down to form a liquid film of the organic solvent having the same chemical structure on the perforated plate to form the mist. By passing through the liquid film, it is dissolved due to its compatibility, and then dropped into the storage section for recovery. Then, the recovered liquid composed of the recovered mist and the organic solvent is supplied again from the upper part of the perforated plate to be useful for recovering the mist. On the other hand, the gas from which the mist has been removed is absorbed by water and removed.

As described above, since the mist passes through the liquid film of the organic solvent having the same chemical structure while being raised,
Since they are brought into contact with each other in the most compatible state, they can be effectively dissolved and captured. The above-mentioned organic solvent, which has captured and increased the amount of mist, is stored in the reservoir, and is supplied again from the upper part of the perforated plate, so that the next mist can be recovered. That is, another mist can be captured and dissolved by the captured and dissolved mist, and the continuous operation can be effectively performed. Furthermore, since the organic solvent forming the liquid film, the mist, and the cleaning liquid in the cleaning tank are organic solvents having the same chemical structure, they are housed in the reservoir.
The liquid can be reused as it is in the washing tank without modifying the components. Therefore, it is possible to prevent the loss of the organic solvent due to the dissipation into the atmosphere.

Further, the gas which has lost the mist can be further absorbed by water to be removed, whereby the lipophilic part of the mist containing the gas can be removed by the organic solvent and the hydrophilic part can be removed by water, so that the gas is almost completely removed. Moreover, harmful components can be removed and pollution can be prevented. Further, the method of the present invention is highly efficient because it can be operated continuously without the trouble of repeatedly performing cooling and heating as in the conventional refrigeration method, and it is also found in the activated carbon method of the conventional example. The continuous operation can be performed without the troublesome maintenance due to the deterioration of the activated carbon, without the troublesome handling such as cooling adsorption and heat desorption, and without the inefficiency of the batch system.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 30 is a cleaning tank for cleaning electronic parts and the like using an organic solvent, and 1 is a main body of a mist treatment device provided in communication with the cleaning tank 30. The mist generated in the cleaning tank 30 (in the present invention, mist includes gas) is communicated with the mist inlet 23 of the mist treatment apparatus 1 and supplied. A recovery tank 4 is provided below the mist treatment device 1. The tank 4 is further provided with a storage part 2 for the recovered liquid at a lower part thereof, and a perforated plate 3 is provided on the storage part 2 with a slight inclination with respect to the horizontal. The porous plate 3 forms a liquid film on the upper surface thereof, and is, for example, a punching metal using an iron plate. The storage section 2 contains the same organic solvent as that used in the cleaning tank 30.

Next, a plurality of the porous plates 3 are provided so as to be inclined in directions opposite to each other as shown in the figure, whereby the length for forming a liquid film on the upper surface is long. Reference numeral 5 denotes a liquid film supply port formed corresponding to the upper part of the perforated plate 3, and is connected to the reservoir 2 by a communication passage 7 having a pump 6. A mist supply port 8 is formed so as to open between the perforated plate 3 and the reservoir 2 of the recovery tank 4. In addition, 5a is a liquid film forming member, and a slit 5b that opens corresponding to the surface of the porous plate 3 is formed.

Reference numeral 5c indicates a guide plate provided in parallel with the porous plate 3. As a result, the mist recovery liquid in the storage section 2 forms a liquid film on the porous plate 3 and is supplied.
Reference numeral 2a indicates a collecting liquid collecting passage provided in the reservoir 2. Reference numeral 9 is a filter for draining the liquid, which is provided on the upper part of the recovery tank 4 and, as an example, a so-called swarf-like metal piece generated by cutting of a machine tool is housed in a basket-shaped container. Note that the filter 9 may be any other known filter as long as it is not affected by the mist to be recovered, such as other synthetic fibers randomly entangled or a synthetic resin continuous porous body.

Reference numeral 10 denotes a recovery chamber formed on the filter 9. The recovery chamber 10 recovers gas after mist recovery, and is provided with a roof-shaped guide 11 and a water tank 12, and the above-mentioned. On the upper part of the guide 11, a contact layer 14 is provided corresponding to the nozzle 13 that jets water. The contact layer 14 is, for example, a basket-shaped container made of metal and containing the so-called swarf-like metal pieces, and the gas-liquid contact is performed in the same layer 14.

The gas that has passed through the filter 9 enters the contact layer 14 and comes into contact with the water 13a sprayed from the nozzle 13 to the layer 14, and is contained in the water 13a and drops onto the guide 11. And is guided by the guide 11 into the water tank 12, and the drain 1
It is supposed to reach 8. The gas-containing water recovered in the water tank 12 is supplied to the nozzle 13 by the second pump 12a and circulated in this manner.

Next, 15 is a filter for draining liquid, and a suction device 16 is provided on the upper part thereof. The device 16 comprises a fan 20 connected to a motor 19. 21
Indicates an exhaust port. Further, 22 is a mist supply pipe, 23 is the mist inlet, 24 is a water supply source, 25 is a recovery tank, 26 is a passage leading to a tank 27, and 28 and 29 are switches respectively.

The mist containing gas is supplied from the mist supply port 8 to the recovery tank 4, and is sucked upward by the suction device 16 provided on the upper portion of the main body 1. In this case, a liquid having the same chemical structure as that of the mist is supplied from the supply port 5 onto the porous plate 3 and flows down while forming a liquid film on the porous plate 3.
Therefore, the mist is absorbed and recovered in the liquid film due to the compatibility while passing upward through the liquid film.

The remaining gas that has lost the mist rises as it is, enters the recovery chamber 10 through the filter 9, exits on the guide 11, enters the contact layer 14, and the nozzle 13 in the same layer 14.
Comes in contact with water 13a jetted from the water, is absorbed by the water 13a, falls on the guide 11 and enters the water tank 12,
It is discharged to the drain 18. The clean air from which the mist and gas have been lost in this way is discharged from the exhaust port 21 into the atmosphere.

[0017]

The present invention is constructed as described above, and the mist of the organic solvent discharged from the cleaning tank is raised in the recovery tank and passes through the liquid film of the organic solvent having the same chemical structure on the way. Therefore, since they are brought into contact with each other in the state of the best compatibility, they can be effectively dissolved and captured. The above-mentioned organic solvent, which has captured and increased the amount of mist, is stored in the reservoir, and is supplied again from the upper part of the perforated plate, so that the next mist can be recovered. That is, another mist can be captured and dissolved by the captured and dissolved mist, and the continuous operation can be effectively performed. Furthermore, since the organic solvent that forms the liquid film, the mist, and the cleaning liquid in the cleaning tank are organic solvents having the same chemical structure, the liquid stored in the reservoir does not change its components and remains as it is. It can be reused in the washing tank. Therefore, it is possible to prevent the loss of the organic solvent due to the dissipation in the atmosphere.

Further, by removing the gas which has lost the mist by further absorbing it with water, the lipophilic part of the mist containing the gas can be removed with an organic solvent and the hydrophilic part can be removed with water. Moreover, harmful components can be removed and pollution can be prevented. Further, the method of the present invention is highly efficient because it can be continuously operated without the trouble of repeatedly performing cooling and heating as in the conventional refrigerating method, and as in the conventional activated carbon method. In addition, continuous operation can be performed without troublesome maintenance due to deterioration of activated carbon, without troublesome handling such as cooling adsorption and heat desorption, and without inefficiency of the batch system.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention and schematically showing an apparatus used for a method for recovering mist of an organic solvent in a cleaning tank for cleaning with an organic solvent.

[Explanation of symbols]

 1 Main Body 2 Reservoir 3 Porous Plate 4 Collection Tank 5 Supply Port 6 Pump 7 Communication Passage 8 Mist Supply Port 9 Filter 10 Collection Chamber 11 Guide 12 Water Tank 13 Nozzle 14 Contact Tank 15 Filter 16 Suction Device 30 Cleaning Tank

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B01D 50/00 501 B01D 50/00 501F 502 502A

Claims (1)

[Claims] 1. A mist of the organic solvent generated in a cleaning tank for cleaning with an organic solvent has a reservoir at the bottom for storing the same organic solvent as the organic solvent, and above the reservoir, In a recovery tank having an inclined porous plate and having a suction device on the upper side, the recovery tank is communicated and supplied between the reservoir and the porous plate, and has the same chemical structure as the supplied mist from the upper part of the porous plate. An organic solvent is allowed to flow down to form a liquid film of the organic solvent having the same chemical structure on the porous plate,
The mist is passed through the liquid film, dissolved by the compatibility with the same chemical structure, the dissolved organic solvent is dropped into the reservoir of the recovery tank to be recovered, and the recovered mist is dissolved in the organic solvent. Furthermore, in a cleaning tank for cleaning with an organic solvent, characterized in that the gas is supplied from the upper part of the perforated plate for forming a liquid film and circulated, while the gas from which the mist has been removed is absorbed and removed by water. Method for collecting mist of organic solvent.