JPH07100447A - Degreasing cleaning method for closed system - Google Patents

Abstract

PURPOSE:To simplify the drainage treatment operation and make equipment compact. CONSTITUTION:Degreasing is carried out in the cleaning process by using pure water fed from a pure water preparation device 1, and the oil-water separation treatment of drain out of the cleaning process is carried out by a first film type oil-water separation device 5, and a part of permeated water passing through a film of the device 5 is returned to the cleaning process, and floated oil content is removed and the remaining portion of permeated water is fed to an ultrafiltration device 7 through a water storage tank 6 and ultrafiltration is carried out. The permeated water passing through the ultrafiltration film is returned to a pure water preparation device 4, and concentrated water not passing through the film is oil-water separated by a second film type oil-water separation device 8 and the permeated water passing through the film of the device 8 is returned to a storage tank 6 and floated oil is removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed system degreasing / cleaning method in which pure water is used as a cleaning liquid for cleaning and degreasing mechanical parts, electronic parts and others.

[0002]

2. Description of the Related Art Conventionally, degreasing cleaning of mechanical parts, electronic parts and the like has been carried out by using a cleaning liquid composed of an organic solvent such as CFC and trichloroethane, an acid or alkaline cleaning liquid and the like.

However, the method using a cleaning liquid composed of an organic solvent has a problem of environmental destruction due to the organic solvent, and therefore its use is being limited, and the development of a solvent replacing it is awaited. On the other hand, in the method that uses an acid or alkaline cleaning solution or a cleaning solution composed of a synthetic detergent, the treatment of cleaning wastewater is essential, and a wastewater regeneration treatment device, a non-renewable wastewater neutralization treatment device, and a biochemical treatment device are required. In addition, each apparatus must be provided with a storage tank, the processing apparatus becomes large and maintenance is complicated.

In view of the above points, an object of the present invention is to use a pure water as a cleaning liquid and to make the system closed, so that the wastewater treatment operation can be simplified and the equipment can be made compact. It is to provide a cleaning method.

[0005]

The closed system degreasing and cleaning method according to the present invention has been devised to achieve the above-mentioned object, and degreasing is performed in the cleaning step using pure water coming from the pure water producing device (1). After cleaning, the wastewater discharged from the cleaning process is separated into oil and water by the first membrane-type oil-water separator (5).
Part of the permeated water that has passed through the membrane in (5) is returned to the washing process, the oil that has floated and separated is removed, and the remaining part of the permeated water is sent to the ultrafiltration device (7) via the water storage tank (6). Ultrapure water treatment equipment and pure water production equipment for the permeated water that has passed through the ultrafiltration membrane
When returning to (1), concentrate water that did not pass through the membrane is
It is characterized in that the membrane-type oil-water separator (8) separates the oil and water, returns the permeated water that has passed through the membrane of the device (8) to the water storage tank (6), and removes the floating-separated oil. .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a flow chart showing a closed system degreasing cleaning method of the present invention.

In FIG. 1, raw water such as city water and industrial water is sent to a pure water producing device (1), and the pure water produced is a cleaning device (9).
Sent to.

The cleaning device (9) includes a pre-cleaning tank (3) and a main cleaning tank.
(2) is provided, and pure water from the pure water producing device (1) enters the main cleaning tank (2). The washing water is supplied from the main washing tank (2) to the pre-washing tank (3) by overflow.

When the object to be cleaned is subjected to the pre-cleaning and then the main cleaning in the cleaning device (9), the cleaning waste water is discharged from the pre-cleaning tank (3) by the drain pump (4) to the first membrane type oil separation device (5). It is sent to and separated into oil and water. Part of the permeated water that has passed through the membrane of the separation device (5) is returned to the pre-cleaning tank (3) for the cleaning process. Further, the oil component floated and separated in the first membrane type oil / water separator (5) is automatically removed from the same device and collected.
As a result, the oil concentration of the cleaning liquid in the pre-cleaning tank (3) is kept low, and the amount of pure water supplied can be reduced.

Remaining permeated water from the first membrane-type oil-water separator (5) (this amount corresponds to the amount of pure water for cleaning which overflows from the main cleaning tank (2) to the pre-cleaning layer (3)) Is sent to the water tank (6). The waste water collected in the water storage tank (6) is sent to the ultrafiltration device (7) by the ultrafiltration water supply pump (10) and subjected to ultrafiltration treatment. Then, the permeated water that has passed through the ultrafiltration membrane is returned to the pure water production device (1), and the concentrated water that has not passed through the membrane is sent to the second membrane oil / water separator (8) for oil / water separation treatment. To be done.

The permeated water that has passed through the membrane of the second membrane type separation device (8) is returned to the water storage tank (6). Further, the oil component floated and separated in the second membrane type oil / water separation device (8) is automatically removed from the device and collected.

Wastewater to the outside of the closed system system is discharged as concentrated water from the pure water producing apparatus (1).

[0013]

Since the closed system degreasing and cleaning method according to the present invention is constructed as described above, it exhibits the following effects.

Since pure water is used as the cleaning liquid, a large-scale device such as a neutralization treatment device or a biological treatment device is not required.

It is possible to easily separate and collect the oil component.

Since pure water is used as the cleaning liquid, the waste water can be regenerated more easily than the conventional method, and the recovery efficiency is high.

As a wastewater treatment device, only a membrane type oil / water separator and an ultrafiltration device need be provided, and the equipment is smaller and more compact than the wastewater treatment equipment in a cleaning device using a chemical detergent.

[Brief description of drawings]

FIG. 1 is a flowchart showing a closed system degreasing cleaning method of the present invention.

[Explanation of reference numerals] 1: Pure water producing device 5: First membrane type oil / water separator device 6: Water storage tank 7: Ultrafiltration device 8: Second membrane type oil / water separator device 9: Washing device

Claims (1)

[Claims] 1. A degreasing cleaning is performed in a cleaning process using pure water coming from a pure water producing device (1), and wastewater discharged from the cleaning process is separated into oil and water by a first membrane type oil and water separating device (5). Equipment (5)
Part of the permeated water that has passed through the membrane is returned to the washing process, the oil that has floated and separated is removed, and the remaining part of the permeated water is sent to the ultrafiltration device (7) via the water storage tank (6) and ultrafiltered. The permeated water that has passed through the ultrafiltration membrane is returned to the pure water production device (1), and the concentrated water that has not passed through the same membrane is separated into oil and water by the second membrane oil-water separator (8). A closed system degreasing and cleaning method characterized in that permeated water that has passed through the membrane of the device (8) is returned to the water storage tank (6), and the oil that has floated and separated is removed.