JPS59166201A - Distillation equipment for solvent cleaning apparatus - Google Patents

Abstract

PURPOSE:To increase the distillation amt. and to reduce the cost of solvent by providing a scraper for scraping vapor foam formed on a vapor generating surface in contact with the vapor generating surface and movably relatively to the vapor generating surface. CONSTITUTION:The solvent to be distilled from a hot bath is introduced into a rotary disk 9 from an intake 13 for a solvent to be distilled through an introducing pipe 8a, and spread from the central part to the circumferential part by centrifugal force due to rotation to form a thin film. The solvent is evaporated by heating the rotary disk with an electric heater 9a. The vapor, passing through vapor discharge ports 14 is cooled in a cooling coil 15, condensed and discharged from a discharge pipe 8b. The concentrated liquid is taken out from a discharge valve 16. The vapor foam 19 generated at the bottom of the rotary disk 9 is forcibly scraped off by chains 18 to be made into solvent vapor.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a distiller that maintains the solvent in the solvent cleaning device clean by distilling the solvent contaminated by the object to be cleaned in the solvent cleaning device. be.

Prior art solvent cleaning equipment has been used to clean oil-contaminated precision equipment (e.g.
This is a device that removes oil and cleans electronic equipment, liquid crystal panels, pumps, etc.) by immersing them in cleaning solvents such as Freon and Triclean, and its structure is shown in Figure 1. It consists of an apparatus main body 1 and a distiller 2, and the inside of the cleaning apparatus main body 1 is composed of three tanks: a hot tub 3, a cooling tank 4, and a vapor tank 5. The object to be cleaned (workpiece) is immersed from the hot tub 3 into the cooling tank 4 and further into the paper tank 5, where it is washed, dried, and taken out.The interior of the hot tub 3 is most contaminated by foreign substances such as oil brought in by the workpiece. This circuit leads the solvent in the hot tub 3 to the distiller 2, heats it with the heater 6, evaporates the solvent, condenses it in the cooling corrugated pipe 7, and returns the distilled solvent to the cooling tank 4. When a cleaning device with such a configuration is operated, foreign substances such as oil in the solvent solution in the distiller 2 increase over time.
The concentration of foreign substances such as oil in the solvent solution in the distiller 2 increases, and the oil floats on the surface of the solution side and evaporates on the surface of the heater 6.The dissolved fumes evaporate on the oil surface, and when the solvent evaporates, the oil and other substances are taken with it. So-called droplet entrainment occurs. To explain this using one specific example, when the oil concentration in the distilled oil ÷ 2 becomes 40 to 50%, the oil reduction rate of the distilled solvent will decrease from 10 mq/l to 40 mq/l.
The cleanliness of the cleaning equipment and the solvent inside the body 1 deteriorated suddenly to J, and the solvent cleanliness inside the body 1 deteriorated, requiring replacement of the V solvent. Therefore, there was a problem in that a large amount of solvent was required at the time of renewal.Object of the InventionThe present invention was made to solve the above-mentioned problems of the prior art. Even if the concentration of foreign substances such as oil in the solvent increases, the amount of distillation can be increased to keep the quality of the distilled solvent constant for a long time, and the time interval for renewing the solvent can be significantly extended1.
An object of the present invention is to provide a distiller in a solvent cleaning device that can reduce solvent costs.

Composition of the Invention In order to achieve the above object, the present invention has the following composition:
A device for scraping steam bubbles generated on the steam generation surface of the cleaning solvent in contact with the steam generation surface of the cleaning solvent in the distiller body for distilling the cleaning solvent is provided, and the scraping tool and the steam generation surface are moved relative to each other. It is characterized by the fact that it is possible.

Embodiment An embodiment of the present invention will be described with reference to the drawings. Figures 2 and 3 show a first embodiment of the present invention; (1) 8r is the distiller main body; A discharge port W8b is connected to discharge the subsequent solvent to a cooling tank (not shown). Reference numeral 9 denotes a rotating disk with a U-shaped cross section for evaporating the solvent, and an electric heater 9a for heating the solvent is attached to the bottom of the rotating disk 9. The rotating disks 9 are arranged in multiple stages, for example, in three stages, and each disk 9 is horizontally fixed to a common rotating shaft 10, and this rotating shaft 10 is rotated by a motor 12 via a pulley 11. , 13 is a distillate solvent inlet for guiding the distillate solvent to the rotating disks 9, and is opened in the center of a tray 13a arranged on the side of each disk 9. ] Solvent vapor discharge ports that evaporate on the four rotating disks 9 and guide the solvent to one side are arranged and fixed in a zigzag pattern around the periphery of each tray 13a with their assigned values being shifted from left to right. has been done. 1
A cooling shaft and tube fixed to the upper part of the 5-box distiller main body 8 condense the solvent vapor evaporated on the rotating disk 9. Reference numeral 16 denotes a discharge valve provided at the bottom of the distiller main body 8, and is for discharging foreign substances such as oil condensed and stored at the bottom of the main body 8.

Reference numeral 17 is a concentrating tank provided at the bottom of the main body 8 to accommodate foreign substances such as oil, and the electric heater 7 installed in this concentrating tank 17 further condenses the solvent to be distilled in the concentrating tank (
80 to 90%), and also to prevent foreign substances such as concentrated oil from solidifying.

18 is a chain for forcibly scraping off steam bubbles generated on the bottom surface of the rotating disk 9,
) The solvent vapor bubbles 19 are located on the bottom surface of the rotary disk 9 and are installed so as to be in contact with the bottom surface of the rotary disk 9 (FIG. 3).

The operation of this embodiment having the above configuration is as follows.

The motor 12 is driven [7 to rotate the rotating disc 9 via the pulley 11 and the rotating shaft 10, while the hot tub (
A solvent to be distilled from a solvent (not shown) is introduced into the rotating disk 9 through an inlet 13 for the solvent to be distilled through an introduction pipe 8a. At this time, the solvent to be distilled is supplied by one rotating disk 9.
In this case, an excess amount that cannot be evaporated is introduced, and the first
The solvent to be distilled that has not been completely evaporated on the rotating disk 9 of the stage overflows and flows into the rotating disk 9 of the next second stage, and in the same way, it sequentially flows into the rotating disk 9 of the lower stage.

The solvent to be distilled introduced into the first-stage rotating disk 9 spreads from the center to the periphery due to centrifugal force as the rotating disk 9 rotates, forming a thin film, and the rotating disk 9 is heated by the electric heater 9IL. As a result, evaporation begins on the surface of the disk 9 and becomes solvent vapor. At this time, the steam bubbles 19 generated at the bottom of the rotating disk 9 collide with the chain 18 and are forcibly scraped off thereby, turning into solvent vapor.

As shown by the solid line arrow in FIG. It is introduced into the rotating disk 9. Here, the solvent to be distilled is again evaporated and the unevaporated solvent is introduced into the third stage rotating disk 9 in the same manner. In this way, the solvent to be distilled that has not been completely evaporated on the rotating disk 9 and overflows sequentially flows into the lower rotating disk 9,
The concentration of oil, etc. in each of the rotating disks 9 in the first, second, and third stages increases toward the bottom, and the distiller main body 8
Bottom i.e. concentration? The concentration of oil, etc. in the solvent in 1J17 is the highest.

On the other hand, the solvent vapor to be distilled that has evaporated on the rotating disk 9 is transferred to the solvent vapor outlet 14 as shown by the broken line arrow in FIG.
The liquid then moves upward through the cooling tube 15, is cooled and condensed, and is supplied to the cooling bath (not shown) via the discharge pipe 8b.

By the way, the solvent vapor bubbles 19 generated at the bottom of the rotating disk 9 form a fluorocarbon vapor bubble film and impede heat conduction from the electric heater 9a.As a result, the overall heat transfer coefficient is dominated by the fluorocarbon vapor bubbles. It will take 7 days. For example, the thermal conductivity of fluorocarbon vapor is 0.0046 Km/m-
H・℃ is extremely small. However, according to this embodiment, the third
Chain 1 with low equipment cost as shown in the figure
8 forcibly scrapes off the fluorocarbon vapor bubbles 19 and greatly increases the overall heat transfer coefficient. As a result, as shown in Fig. 4, the distillation amount can be increased by 10% compared to the case without the chain. did it.

Although a hanging chain was used in this embodiment as a means for scraping off steam bubbles, other means such as a thin round bar or a plate made of Teflon or the like that runs along the bottom surface of the rotating disk 9 and has low resistance to solvents may be used as a means for scraping off steam bubbles. A scraping tool may also be used.

According to this embodiment, since the hot bath liquid, which is the solvent to be distilled, is not directly flowed into the concentrated liquid in the concentrating tank 17 as in the conventional apparatus, even if the oil concentration at the bottom of the distillation main body 8 reaches 80%, A highly clean distillate with an oil content of 10 mg/l or less was borrowed. Therefore, in the conventional equipment, the oil concentration is 40
While it was necessary to replace the solvent in the cleaning device when the concentration reached ~50%7, in this example, even if the oil concentration at the bottom of the distiller main body 8 was 80%, there was no need to replace the solvent, and the concentrated liquid was removed from the discharge valve 1.
It was only necessary to remove it from 6, and the cost of solvent could be reduced significantly.

In this embodiment, the rotating disk 9 applies centrifugal force to the solvent to be distilled, so the solvent flows on the disk 9, reducing the thickness of the film and increasing the thermal conductivity.
It is also possible to increase the distillation 1: compared to conventional equipment.

In addition, the number of rotating disks 9 (number of stages) is further increased fr
-t) The amount of distillation can be easily increased by increasing the number of rotations of the rotating disk 9.

In this embodiment, the electric heater 9a was used as the force source 2 for the rotating disk 9, but instead of this, the rotating disk 9
A hot water circuit may also be provided in the rotary shaft 10 to evaporate the cleaning solvent by heating the hot water.

FIG. 5 shows a second embodiment of the present invention. This embodiment is applied to a distiller with a small distillation volume, and unlike the first embodiment, a rotating disk is not used, and the solvent is evaporated only on the bottom plate 20 of the distiller main body 8, so that K'IP3 is generated on the surface of the bottom plate 20. The solvent vapor bubbles 19 are scraped off by rotating an arm 22 attached to a scraping tool of the chain 18 via a rotary shaft 23 rotated by a motor 21.

Even with this configuration, the distillation amount can be reduced by about 1 compared to the conventional example.
We were able to increase it by 0%.

Effects of the Invention The present invention forcibly scrapes off steam bubbles generated on the solvent vapor generation surface in the distiller main body, and eliminates the effect of lowering thermal conductivity due to these bubbles, so it is possible to increase the distillation amount. Therefore, even if the concentration of foreign substances such as oil in the solvent to be distilled increases, the quality of the distilled solvent can be maintained constant for a long time, significantly extending the time interval for replacing the solvent, and reducing solvent costs. It has the effect of being able to.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a conventional solvent cleaning device, FIG. 2 is an enlarged vertical cross-sectional view of the first actual #i second', l of the present invention, and FIG.
FIG. 4 is a graph showing a comparison of the distillation amount between the above example and the conventional example, and FIG.
FIG. 3 is an enlarged vertical cross-sectional view of the embodiment. DESCRIPTION OF SYMBOLS 1... Cleaning device main body, 2... Distiller, 8... Distiller main body, 9... Rotating disk, 9a... Electric heater, 10... Rotating shaft, 13a... Tray, 18
... Chain, 19 ... Steam bubble, 20 ... Bottom of distiller body, 22 ... Arm, 23 ... Rotating shaft. Patent Applicant: Nippondenso Co., Ltd. Patent Attorney: Akira Yoiki, Patent Attorney: Kazuyuki Nishidate] Kyosuke Yuri, Patent Attorney: Akira Yamaguchi, Patent Attorney: Figure 2 19 Figure 4: Rotation speed (rpm)

Claims (1)

[Scope of Claims] 1. In contact with the vapor generating surface of the cleaning solvent in the distiller main body for distilling the cleaning solvent. A distiller for a solvent cleaning device, characterized in that a tool for scraping off steam bubbles generated on a steam generating surface of a lever is provided, and the scraping tool and the steam generating surface are movable relative to each other. 2. The distiller for a solvent cleaning device according to claim 1, wherein the steam generating surface is rotatable. 3. The distiller for a solvent cleaning device according to claim 1, wherein the steam bubble scraping tool is rotatable. 4. The distiller for a solvent cleaning device according to claim 1, which uses a chain suspended from the steam bubbles as a V group.