JP2617548B2 - Dry cleaning method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a dry cleaning method using an organic solvent such as perchlorethylene, fluorocarbon 113, and 1.1.1 trichloroethane.

(Prior Art) A conventional dry cleaning step will be outlined with reference to FIG. First, the clothes 2 are put in from the door 1, and when the door 1 is closed and the operation is started, the steps generally proceed in the following order.

. The solvent 4 is pumped from the solvent tank 3 via the valve 5 by the pump 6, and the required amount of the solvent 4 is fed into the processing tank 10 through the path including the valve 7 and the filter 8 or the path including the valve 9.

. The processing drum 11 is slowly rotated to remove the solvent 4 from the processing tank 10,
The clothing 2 is circulated through a circuit consisting of a button trap 12, a valve 13, a pump 6, a valve 7, a filter 8 or a valve 9.
Wash.

. The liquid is drained through the processing tank 10, the button trap 12, the valve 13, the pump 6, the valve 14, and the distilling device 15, and then the processing drum 11 rotates at a high speed to centrifuge the solvent 4 in the clothing 2, and similarly. Drain.

. The above steps are repeated.

. Processing tank 10, Button trap 12, Valve 13, Valve 5
The solvent 4 is centrifuged and drained in the path of (1).

. The processing drum 11 is slowly rotated again, and a recovery air duct 19 including a fan 16, an air cooler 17, and an air heater 18 is provided.
Then, the clothes 2 are dried by circulating air in the direction of arrow 20 by the fan 16 between the processing tanks 10. The solvent gas evaporated from the garment 2 is condensed by the air cooler 17 and collected by the recovery path 21.
Then, the water enters the water separator 22 and returns to the clean tank 24 through the solvent pipe 23.

. When drying is completed, the dampers 25 and 26 open as indicated by broken lines, take in fresh air from the damper 25, exhaust non-condensed solvent gas that cannot be recovered by the air cooler 17 from the damper 26, and deodorize the solvent odor in the clothing 2.

. The solvent 4 that has entered the still 15 in the above step evaporates and is condensed and recovered by the condenser 27, enters the clean tank 24 through the water separator 22 and the solvent pipe 23, and enters the solvent tank from the overflow-equipped partition plate 28. Return to 3. The water separated by the water separator 22 is discharged out of the system by a water pipe 29.

Next, a conventional solvent recovery apparatus will be described with reference to FIGS. The solvent gas evaporated from the clothing 2 in the drying step is cooled by the air cooler 17 and condensed and recovered. The air cooler 17 usually cools the solvent gas to about 32 to 35 ° C. because well water is used in a water-cooled manner. Then, the solvent gas is condensed and recovered, but the concentration of the solvent gas contained in the air does not fall below the saturation concentration determined by the temperature and pressure at that time.

For example, in the case of perchlor ethylene, the cooling temperature is
At about 35 ° C., the concentration of the solvent contained in the air cannot be reduced to 250 g / m ³ or less, and a strong odor remains in the clothing 2 as it is.

Therefore, in the deodorizing step described above, the processing drum 11 is rotated to remove the residual odor, the damper 25 is opened to take in a large amount of outside air, and this is brought into contact with the clothing 2 to dilute the solvent gas concentration, and Exhaust from 26 to outside.

However, although the exhaust gas of the conventional apparatus is diluted, it contains solvent gas that reaches tens of thousands ppm at the beginning, and causes a problem of air pollution. Freon 11 or Freon
When 113 is released into the atmosphere, the depletion of the ozone layer surrounding the earth has become a problem, and there is an international movement to curb production. Therefore, in the conventional apparatus shown in FIG.
The diluted solvent gas discharged from 26 is led to a solvent recovery device 30 shown in FIG. 4 through a duct 37, and the activated carbon layer 32 in the solvent recovery device 30 is brought into contact with and adsorbs the solvent gas. As a result, it is released to the atmosphere as clean air.

When the ability of the activated carbon layer 32 to recover the solvent gas reaches saturation, steam is blown from the steam pipe 33 onto the activated carbon to evaporate the solvent in the activated carbon, so-called desorption. The evaporated solvent gas is condensed and liquefied by a water-cooled condenser 34, separated into water and a solvent by a water separator 35, and the solvent is collected in a clean tank 24. When the desorption process is completed,
Fresh air is sent in by the drying fan 36, and the activated carbon layer 32
Is dried and regenerated to prepare for the next adsorption step. The method described above is a solvent recovery method performed in a conventional general deodorization step.

However, as described above, the conventional solvent recovery apparatus takes in a large amount of outside air, dilutes the solvent gas concentration in the apparatus (processing tank and recovery), and exhausts the solvent gas while rotating the processing drum 11 to the outside of the apparatus. Therefore, the processing amount of the solvent gas inevitably increases, and the solvent recovery device 30
However, the running cost such as the apparatus cost, the installation area, and the recovered energy becomes expensive, and these are major factors that hinder the installation of the solvent recovery apparatus 30.

As described above, in the conventional solvent recovery apparatus, a large amount of outside air is taken in and the processing drum is rotated to recover the solvent gas in the apparatus while diluting the solvent gas.

In response to this problem, the present inventors previously disclosed in Japanese Patent Application No. 63-111898, the rotation of the processing drum was stopped during the deodorizing step, and outside air was taken in from the upper opening provided in the upper part of the processing tank or the recovery air duct, and the processing was performed. From the lower opening provided in the lower part of the tank or the button trap part, the solvent gas in the processing tank is slowly exhausted so that the solvent gas in the processing tank is not agitated by the exhaust means connected to the solvent recovery device while the processing drum is stopped, and the solvent in the processing tank is exhausted. By replacing the gas and simultaneously supplying the solvent gas to the solvent recovery device one or several times, a new method has been proposed which can solve the above problem.

FIG. 5 shows a conventional apparatus showing this method. The difference from FIG. 3 is that the upper part of the recovery air duct 19 or the processing tank 10
The solvent gas in the apparatus is slowly exhausted from the lower opening of the processing tank 10 or the lower opening of the button trap 12 to the small solvent recovery device 30a while the rotation of the processing drum 11 is stopped, while taking in outside air from the upper opening of the upper part of the processing tank 10. As valve 50a or 5
0b and the duct 47a or 47b.

Next, a conventional small solvent recovery device 30a shown in FIG. 6 will be described. The device 30a has an activated carbon layer 42 having a capacity of about 1/10 of the conventional capacity at the center, and is used for suctioning solvent gas. And a desorption steam pipe 43 including a regeneration drying fan 46 of activated carbon and valves 51, 52, 53 for circuit switching, and further including a steam valve 54 for desorption of the solvent adsorbed on the activated carbon.
A water-cooled condenser 44 for condensing and recovering the evaporated solvent is provided.

The conventional small-sized solvent recovery device 30a configured as described above
By incorporating this into a dry cleaning device, the amount of gas processing required to recover a certain amount of solvent in the processing tank is reduced, and the solvent recovery device can be made much smaller than before, thus preventing air pollution and preventing ozone layers. Resource saving by destruction prevention and solvent recovery can be achieved.

(Problems to be Solved by the Invention) As described above, the conventional air pollution problem can be expected to be greatly improved by the technique disclosed in Japanese Patent Application No. 63-111898, and the cost required for solvent recovery is also reduced. Although it was greatly reduced, the running cost (steam fee, cooling water fee, etc.) was still required for the solvent recovery section.
Regular maintenance was required.

Further, as a recent tendency, a method called a closed system in which a solvent gas in a dry cleaning device is not deodorized has been often used. However, in such a dry cleaning apparatus, when the clothes are taken out by opening the door after the end of the process, the solvent gas remaining in the processing tank flows out into the working chamber, causing a deterioration in the working environment.

An object of the present invention is to provide a dry cleaning method capable of solving the problems such as the running cost of the solvent recovery section, the periodic maintenance, and the deterioration of the working environment in a closed system at once.

(Means and Actions for Solving the Problems) For this reason, in the present invention, in the deodorizing step, while the rotation of the processing drum is stopped, outside air is taken in from the upper opening provided in the upper part of the processing tank or the recovery air duct, The solvent gas in the processing tank is slowly evacuated from the lower opening provided in the lower part of the processing tank or the button trap part so as not to stir the processing drum by the air supply device while the processing drum is stopped, and at the same time, the solvent gas is sent to the air reservoir. After that, the door of the processing tank is opened to take out the washed clothes, then the unwashed clothes are thrown in, and the door is closed. At the same time as returning the solvent gas to the processing tank, the air in the processing tank is allowed to escape from the upper opening, and this serves as a means and an action for solving the problem.

(Embodiments) The present invention will be described below with reference to the embodiments in the drawings.
FIG. 2 is a system diagram of a dry cleaning apparatus showing an embodiment of the present invention, and FIG. 2 is a perspective view of an air box which replaces the air bag of FIG. In FIG. 1, the same parts as those in the related art (FIG. 3) will be described using the same reference numerals. In the figure, 1 is a door, 2 is clothing, 3 is a solvent tank,
4 is a solvent, 5 is a valve, 6 is a pump, 7 is a valve, 8 is a filter, 9 is a valve, 10 is a processing tank, 11 is a processing drum,
12 is a button trap, 13 and 14 are valves, 15 is a still, 16
Is a fan, 17 is an air cooler, 18 is an air heater, 19 is a recovery air duct, 22 is a water separator, 23 is a solvent pipe, 24 is a clean tank, 27 is a condenser, 28 is a divider with overflow, 29 is a water pipe, Since these are the same as those in the case of FIG. 3, detailed description thereof will be omitted here.

Next, the difference between FIG. 1 and FIG. 3 will be described. While taking in outside air from the upper opening of the recovery air duct 19 or the upper opening of the processing tank 10, the lower opening of the processing tank 10 or the lower opening of the button trap 12 is taken. In order to slowly exhaust the solvent gas in the apparatus to the air supply device 60 while the rotation of the processing drum 11 is stopped, a third connection point is provided through a valve 50a or 50b and a duct 47a or 47b. Although different from the figure, the point that the valves 50a and 50b and the ducts 47a and 47b are provided is shown in FIG. However, the difference between FIG. 1 and FIG. 5 is that the air supply device 60 and the airbag 61 are connected to the duct 47a in FIG.
Or 47b, and valves 62 to 65 for switching the direction of air flow are provided.

FIG. 2 shows an air box which replaces the air bag 61 of FIG.
It is a perspective view showing the details of 70, 71 is a solvent gas inlet and outlet, 72
Is an air inlet / outlet.

Next, the operation when the airbag 61 is incorporated in the dry cleaning device as in the embodiment of FIG. 1 configured as described above will be described.

First, the dry cleaning device performs the prescribed cleaning as before,
When the drying step is completed, after stopping the processing drum 11, the damper 26a or 26b, which is the upper opening for taking in outside air, is opened as shown by a broken line, and the solvent gas in the apparatus and the damper 26a or 26b from the damper 26a or 26b are opened via the valve 50a or 50b. With a small air flow that does not allow the outside air to mix, and blow the solvent gas inside the machine in the direction of arrow 20a,
2. The air is supplied to the airbag 61 via the air supply device 60 and the valve 63 for a certain period of time. At this time, the valves 64 and 65 are closed. By this operation, outside air is taken into the processing tank 10 via the damper 26a or 26b.

Next, the door 1 is opened, the washed clothes 2 are taken out, and then the unwashed clothes 2 are put in and the door 1 is closed. Next, while the damper 26a or 26b is open, the solvent gas in the airbag 61 is now supplied by the air supply device 60 to the valve 64 and the air supply device.
60, the valve 65, and the valve 50a or 50b are fed from the lower part in the processing tank 1 through the path, and the air in the processing tank 1 is discharged from the damper 26a or 26b to the outside of the system. In this embodiment, the case where the solvent gas in the processing tank 1 is received in the airbag 61 has been described. However, the same function can be obtained by receiving the solvent gas in the air box 70 as shown in FIG. Further, in the present embodiment, as a method of returning the solvent gas in the airbag 61 into the processing tank 1, the pushing method by the air supply device 60 is employed, but the absorption method by the air supply device 60 from the dampers 26a and 26b is reversed. Of course, the air in the processing tank 1 may be sucked, and the solvent gas in the airbag 61 may be taken in from the valve 50a or 50b by setting the inside of the processing tank 1 to a negative pressure. The point of the present invention is to utilize the property that the solvent gas is much heavier than air and hardly diffuses.

(Effects of the Invention) Since the present invention is configured as described in detail above, when taking out clothing from the dry cleaning device, the amount of solvent gas leaking from the door portion to the workplace can be minimized, and therefore good In addition to maintaining a safe working environment, the worker is also free from strong solvent smell when the door is opened. In addition, according to the present invention, the solvent gas that has flowed out to the work place is stored in the air reservoir and returned to the dry cleaning device again, so that it has a remarkable effect in reducing solvent loss and further reducing fluorocarbon pollution. Things.

[Brief description of the drawings]

FIG. 1 is a system diagram of a dry cleaning apparatus showing an embodiment of the present invention, FIG. 2 is a perspective view of an air box replacing the air bag of FIG. 1, FIG. 3 is a system diagram of a conventional dry cleaning apparatus, FIG. 4 is a piping diagram of a conventional solvent gas recovery device, FIG. 5 is a system diagram of another conventional dry cleaning device, and FIG. 6 is a piping diagram of another conventional recovery device. Explanation of main parts in the drawing 10 Processing tank 11 Processing drum 12 Button trap 26a, 26b Damper 50a, 50b Valve 60 Air supply device 61 Airbag (air reservoir) 70 … Air box (air reservoir)

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-146586 (JP, A) JP-A-63-63498 (JP, A)

Claims (1)

(57) [Claims] In the deodorizing step, while the rotation of the processing drum is stopped, outside air is taken in from an upper opening provided in an upper part of the processing tank or a recovery air duct, and a lower part provided in a lower part of the processing tank or a button trap part. The solvent gas in the processing tank is slowly evacuated from the opening so as not to stir, while the processing drum is stopped by the air supply device.At the same time, after the solvent gas is sent to the air reservoir, the door of the processing tank is opened and washed. After taking out the already-washed clothes, then putting in the unwashed clothes and closing the door, the solvent gas is returned from the air reservoir to the processing tank through the lower opening of the processing drum by the air supply device, and at the same time, the inside of the processing tank is removed. A dry cleaning method characterized by allowing air to escape from an upper opening.