JPH0532563A - Apparatus for regenerating organic solvent - Google Patents

Abstract

PURPOSE:To provide an apparatus for regenerating organic solvent effective for preventing the deposition of impurities on the surface of a heater and enabling the regeneration of an organic solvent over a long period in high efficiency. CONSTITUTION:The objective apparatus for the regeneration of an organic solvent contains a heater 62 in a distillator 6. The circumferential wall 611 of the distillator 6 has a double-wall structure consisting of an inner wall 611a and an outer wall 611b overlapped each other interposing a prescribed space 7 therebetween. The heater 62 is placed in the space 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic solvent regenerator.

[0002]

2. Description of the Related Art Conventionally, in the process of manufacturing a printed circuit board, after forming a circuit, a solder resist forming process of printing a resist ink to protect the circuit is performed. The resist coating plate used in this step and the resist ink adhered to the printed circuit board where printing has failed are, for example, 1.
1.1. Washed with an organic solvent such as trichloroethane. In order to save the organic solvent, the organic solvent once used for cleaning is extracted from the cleaning waste liquid by the organic solvent reclaiming device to be regenerated and used again for cleaning.

As an organic solvent regenerator, for example, as shown in FIG. 3, a cleaning waste liquid is collected and temporarily stored in a dirty tank 1, and the cleaning waste liquid is pumped from the dirty tank 1 to a primary separation tank 3 by a pump 2 to In the separation tank 3, relatively large solid or semi-solid impurities mainly consisting of resist are precipitated, and the supernatant liquid is introduced into the secondary separation tank 4 and relatively in 3 or 4 stages in the secondary separation tank 4. After the small solid or semi-solid impurities are precipitated, the organic solvent in which the impurities are dissolved is pumped to the distiller 6 by the pump 5, and the organic solvent distilled by the distiller 6 is introduced to the water separation tank 7. After removing water, the liquid storage tank 8
In some cases, the liquid is stored in the storage tank 8 and is supplied again as the cleaning liquid from the storage tank 8. In this conventional apparatus, the liquid storage tank 8 is replenished with new liquid at any time via the new liquid tank 9, and a required amount of organic solvent is supplied as a cleaning liquid to the plate cleaning machine or the substrate cleaning machine.

In the distiller 6, a heater 62 is arranged in a lower portion of a substantially rectangular vessel 61, and vapor of about 100 ° C. is circulated in the heater 62 to heat an organic solvent in which impurities are dissolved. In this way, the cooler 63 arranged above the container can 61 cools and agglomerates the organic solvent vaporized by the heating by the heater 62, and further collects the agglomerated organic solvent in the collecting container 64. It has become. A pipe 10 for guiding the organic solvent to the water separation tank 7 is further connected to the recovery container 64.

[0005]

By the way, since the above-mentioned resist is mainly composed of a thermosetting synthetic resin such as an epoxy resin, it is hardened when heated in the distiller 6 to be solid or semi-solid. become. Conventional distiller 6
In order to increase the thermal conductivity, the heater 62 is so arranged as to be bare in the lower portion of the container 61 and is immersed in the treatment liquid. Since the solidified resist is solidified and adheres to the surface of the heater and is gradually deposited, the solidified resist is deposited on the surface of the heater 62 in a short time, the heat transfer efficiency is significantly reduced, and the organic solvent is less likely to be vaporized. There is a problem that the solvent cannot be separated.

Another problem is that the work of removing the resist that has accumulated from the surface of the coil-shaped pipe that constitutes the heater 62 is considerably troublesome and time-consuming. The present invention has been made in view of the above circumstances, and provides an organic solvent regenerator capable of highly efficiently regenerating an organic solvent for a long period of time by preventing the accumulation of impurities on the heater surface. The purpose is to

[0007]

In order to achieve the above object, the present invention is based on the premise of an organic solvent regenerator in which a heater 62 is provided in a distiller 6 as shown in FIG. The inner wall 611a and the outer wall 611b are arranged so that the peripheral wall 611 of 6 overlaps the inside and outside with a predetermined space 7 in between.
It is an organic solvent regenerator characterized in that the heater 62 is arranged in the space 7 and is composed of a double wall consisting of

The inner peripheral surface 611e of the distiller 6 may be formed into a cylindrical surface, and the impeller 11 that rotates while advancing and retracting along the axis may be provided inside.

[0009]

In the present invention, the heater 62 has the inner wall 611a.
Since it is arranged in the space 7 formed between the outer wall 611b and the outer wall 611b, the resist dissolved in the organic solvent does not come into contact with the surface of the heater 62, and the resist may be hardened and deposited on the surface of the heater 62. Disappears. Above impeller 1
1 has a function of preventing the hardened impurities from adhering to the inner peripheral surface 611e of the distiller 6.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. The organic solvent regenerator according to one embodiment of the present invention has the same structure as that of the above-mentioned embodiment except for the structure of the distiller. Therefore, the distiller will be mainly described here.

As shown in FIG. 1, a can 61 of the distiller 6 is provided.
Is a cylindrical peripheral wall 611, a ceiling wall 612 that closes the upper end surface thereof, and an inverted conical bottom wall 613 that is connected to the lower end thereof.
It has and.

The portion of the peripheral wall 611 below the middle portion is formed of a double wall composed of an inner wall 611a and an outer wall 611b which are arranged so as to overlap the inside and outside with the space 7. The upper and lower sides of this space 7 are the upper plate 611c and the lower plate 61.
The heater 62 is closed by 1d, and a heater 62 formed of a coiled pipe is provided therein. This heater 62 has about 10
The steam at 0 ° C. is circulated.

Further, a cooler 63 consisting of an inner and outer double coiled pipe is arranged in the upper part of the container can 61, and cooling water of 4 to 6 ° C. is circulated in the cooler 63, for example. is there. Below the cooler 63, a recovery container 64 for receiving the organic solvent condensed by the cooler 63 is provided, and a pipe 10 for guiding the organic solvent from this to the water separation tank 7 is connected to the recovery container 64.

The inner peripheral surface 611e of the container can 61 is formed as a stepped cylindrical surface having a double wall portion with a small diameter. Inside the container can 61, an impeller rotating while moving up and down along the axis thereof. 11 is provided.

The impeller 11 is externally fitted to a screw shaft 12 arranged on the shaft center of the distiller 6 in the distiller 6 so as to be able to move forward and backward, and is rotated by a driving device 13 so that the impeller 11 extends along the screw shaft 12. Move up and down.

The drive unit 13 is a motor 131 arranged on the top wall 612 of the container 61 and capable of rotating in the forward and reverse directions. The drive sleeve 135 is screwed through a worm roller 132, a worm wheel 133 and an intermediate transmission shaft 134. It is configured to be driven to rotate about the axis of the shaft 11.

As shown in FIGS. 1 and 2, the screw shaft 11 and the center boss 11a of the impeller 11 screwed to the screw shaft 11 are inserted into the hollow portion 135a of the drive sleeve 135, and the peripheral wall 135b thereof is provided. A plurality of vertical grooves 135c are formed through which a plurality of blade-attaching side bosses 11b protruding in a radial direction from the center boss 11a of the impeller 11 are inserted so as to be slidable up and down.

Therefore, the rotation of the drive sleeve 135 is transmitted to the impeller 11 via the side bosses 11b inserted in the vertical grooves 135c, and the side bosses 11b are rotated in the vertical grooves 135c by the rotation of the impeller 11. The bosses 11a move up and down in the hollow portion 135a.

The impeller 11 has the center boss 11a.
In addition to the side boss 11b, a plurality of blades 11c attached to each side boss 11b are provided, and each blade 11c extends to a position that approaches the inner peripheral surface 611e of the inner wall 611a in the radial direction by, for example, about 1 to 2 mm. Will be issued.

The organic solvent in which the resist is dissolved is shown in FIG.
As shown in (1), the secondary separation tank 4 is introduced into the distiller 6 from the introduction can 68 by the pump 5. As a result, when the float 66 floating on the liquid surface reaches the height of the upper limit level sensor 65a, the pump 5 is stopped and the heater 62 becomes 100
The heating is started by circulating the steam of ℃. However, the heating may be started at the same time as the operation of the pump 5 is started.

Heating by the heater 62 is started and the container 6
Before the liquid temperature in 1 reaches a predetermined value, circulation of cold water of, for example, 4 ° C. to the cooler 63 is started, and the driving device 13
Is started, and the impeller 11 is rotated and moved up and down to stir the liquid in the container 61.

When the temperature of the liquid in the container can 61 reaches a predetermined value, only the organic solvent component of the liquid in the container can 61 starts to evaporate, and the impurities containing the resist as a main component remain in the liquid that has not evaporated. To remain. The evaporated organic solvent component is cooled by the cooler 63, aggregated and collected in the collection container 64. The organic solvent collected in the recovery container 64 is guided to the water separation tank 7 through the pipe 10 to remove water, and then the liquid storage tank 8
Is stored as a cleaning liquid and supplied to a plate cleaning machine, a substrate cleaning machine, and the like.

When the float 66 floating on the liquid surface is lowered to the height of the lower limit level sensor 65b, the operation of the pump 5 is restarted, the organic solvent having impurities dissolved therein is introduced into the distiller 6, and the distillation of the organic solvent continues. Done. Further, the separated impurities are semi-solidified (gel state) and are collected at the bottom of the vessel 61. If a certain amount is collected, the supply of the organic solvent in which the impurities are dissolved is stopped and the bottom wall 613 is provided with a lower end. The extraction valve 67 provided is opened to discharge impurities.

The impurities heated by the heater 62 begin to harden from the vicinity of the inner peripheral surface 611e of the inner wall 611a, but since the heater 62 is not in direct contact with the organic solvent, the impurities which become semi-hardened by the heating of the organic solvent. Does not directly adhere to the heater 62, the thermal conductivity does not decrease, and maintenance of the heater 62 does not take time.

Further, the impeller 1 is used as an organic solvent containing impurities.
Since the heating is performed while stirring at 1, the impurities that have begun to harden from the vicinity of the inner peripheral surface 611e as described above are not contained in the container 61.
It becomes difficult to adhere to the inner peripheral surface 611e. And container 6
Even if it adheres to the inner peripheral surface 611e of No. 1, the impeller 11
Since it is scraped off by the inner surface 611e of the container can 61, a certain amount or more of the inner surface 611e of the container can 61 is not attached.
There is no fear that the thermal conductivity from 11e to the organic solvent containing impurities will drop below a certain level, and the regeneration treatment of the organic solvent can be performed with high efficiency for a long period of time.

In the above embodiment, the heater 62 is composed of a coiled pipe, but it may be a cylindrical panel or a coil band. It is also possible to use electric heat instead of steam heat as a heat source. Further, the heat of the heater 62 is prevented from reaching the bottom wall 613, and the impurities that become semi-solid and sink into the bottom wall 613 are not further cured, so that the removal is facilitated.

[0027]

As described above, according to the present invention, since the peripheral wall of the evaporator is made into a double wall which overlaps the inside and outside, and the heater is arranged in the space between the double walls, the heater is solidified and separated. There is no risk of being buried between the impurities that have been formed or solidified on the surface of the heater and being wrapped in the accumulated impurities.In addition, since the inner surface of the peripheral wall is a vertical surface, impurities will also adhere to the inner peripheral surface of the peripheral wall. Since it becomes difficult to deposit, the heat generation of the heater can be efficiently transmitted to the organic solvent containing impurities for a long period of time, and the effect of highly efficiently regenerating the organic solvent for a long period of time can be obtained.

In the present invention, in particular, when the inner peripheral surface of the still is formed as a cylindrical surface and an impeller that rotates while advancing and retracting along the axis is provided inside, the organic solvent containing impurities is agitated. Since it is heated while being heated, the organic solvent containing impurities is evenly heated, and in particular, solidification of impurities does not start from the inner peripheral surface, and it becomes more difficult for impurities to adhere to or accumulate on the inner peripheral surface. . As a result, the effect that the organic solvent can be regenerated with high efficiency over a longer period of time can be obtained.

Further, particularly when this impeller is provided, if the tip of the impeller is brought close to the inner peripheral surface of the distiller,
Impurities accumulated on the inner peripheral surface of the still can be scraped off with an impeller, and the impurities will not accumulate on the inner peripheral surface of the still more than a certain amount, so that the organic solvent can be highly efficiently used for a longer period of time. The effect that reproduction can be performed is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a still according to an embodiment of the present invention.

FIG. 2 is a cross-sectional plan view taken along the line AA of FIG.

FIG. 3 is a schematic configuration diagram of a general organic solvent regeneration device.

[Explanation of symbols]

6 Distiller 7 space 11 impeller 62 heater 611 peripheral wall 611a inner wall 611b outer wall 611e inner peripheral surface

Claims (3)

[Claims] 1. An organic solvent regenerator in which a heater (62) is provided in a still (6), wherein a peripheral wall (611) of the still (6) overlaps the inside and outside with a predetermined space (7). Inner wall (611a) and outer wall (611a)
An organic solvent regenerator characterized in that the heater (62) is arranged in the space (7) and is composed of a double wall consisting of b) and b). 2. The organic material according to claim 1, wherein the inner peripheral surface (611e) of the distiller (6) is formed into a cylindrical surface, and an impeller (11) that rotates while advancing and retreating along the axis is provided inside. Solvent recycling device. 3. The organic solvent regenerator according to claim 2, wherein the tip of the impeller (11) is brought close to the inner peripheral surface (611e) of the distiller (6).