JPH0414598B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvements in dry cleaning equipment.

[Conventional technology]

First, an outline of a conventional dry cleaning apparatus will be explained with reference to FIGS. 2 and 3.

In the figure, 10 is a processing tank. When the door 1 provided in the processing tank is opened and the clothes 2 to be cleaned are put into the processing tank, and the door 1 is closed to start operation, the process normally proceeds as follows according to the cycle diagram shown in Figure 3. The dry cleaning process then proceeds. The organic solvents used in dry cleaning include perchlorethylene, 1,
1,1-trichloroethane, 1,1,2-trichloro-1,2,2-trifluoroethane (R113), trichloromonofluoromethane (R11)
However, in the following explanation, it is assumed that perchlorethylene is used.

Pre-washing step (1) By operating the pump 6, the solvent 4 stored in the solvent tank 3 is pumped up through the valve 5, and passes through the valve 7 and the filter 8.
Alternatively, the required amount is fed into the processing tank 10 via a route passing through the valve 9.

(2) Subsequently, the distance drum 11 in the processing tank 10 is slowly rotated, and the solvent 4 is discharged from the processing tank 10 via the button trap 12, valve 13 and pump 6, and then passes through the valve 7 and filter 8. It is circulated to the processing tank 10 through a route or a route passing through a valve 9 . The clothing 2 is washed by circulation of this solvent.

Drainage process (3) When the cleaning for a predetermined period of time is completed, the solvent in the treatment tank 10 passes through the button trap 12, valve 13, pump 6, and valve 14, and then flows into the distiller 1.
The liquid is drained at 5. Subsequently, the processing drum 11 rotates at high speed to centrifugally separate the solvent 4 in the clothing 2 and drain it. The solvent entering the distiller 15 is evaporated and led to the condenser 27, where the solvent vapor is condensed and recovered. The solvent recovered here is introduced into the water separator 22 to separate the water contained therein, and then sent to the cleaning tank 24 through the solvent pipe 23, and then sent to the solvent tank 24 from the overflow partition plate 28. will be returned.

Main washing step (4) By repeating steps (1) and (2) above, the desired degree of washing is obtained.

Drainage process (5) After draining the solvent from the processing tank 10 to the tank 3 through the route of the button trap 12, valve 13, and valve 5, the processing drum 11 rotates at high speed, and the clothing 2
The solvent 4 adhering to the liquid is discarded by centrifugation.

Drying Step (6) While slowly rotating the processing drum 11 again, air is circulated between the processing tank 10 and the recovery air duct 19 in the direction shown by the arrow 20 in the figure to dry the clothing 2. Recovery air duct 19
is fan 16, air cooler 17, air heater 1
The solvent gas evaporated from the clothing 2 is condensed in the air cooler 17. This condensate is introduced into a water separator 22 via a recovery path 21, where water is separated, and then sent to a cleaning tank 24 through a solvent pipe 23.

Deodorizing Step (7) When the drying step described above is completed, the dampers 25 and 26 of the recovery air duct 19 are opened as shown by broken lines in the figure. By taking in fresh air from this open part, uncondensed solvent gas that cannot be recovered by the damper 26 is exhausted, and the clothing 2
Deodorizes residual solvent odor.

In addition, 30 in the figure is a steam pipe, and the air heater 18
It was provided as a heating means. Also,
A cooling water pipe 31 is provided as a cooling means for the condenser 27. 32 and 33 are steam pipes provided as heating means for the distiller 15.

The heating by the steam pipe 32 is to distill the solvent drained into the distiller 15 by heating it from the surroundings (indirect distillation), which is generally called continuous distillation because it is automatically executed in step (3) above. has been done. When indirect distillation is performed, solid dirt and oily dirt accumulates inside the distiller 15 as distillation scum, but if this accumulates too much, the distillation effect decreases and eventually distillation becomes impossible, so daily work is completed. Be sure to take the time to remove it.

The heating by the steam pipe 33 is to directly heat and distill the solvent drained into the distiller 15 (direct distillation), and when expelling the solvent gas contained in the distillation residue prior to indirect distillation, etc. Direct heat distillation is performed by operating the valve of the steam pipe 33.

By the way, in the case of the conventional dry cleaning apparatus shown in FIG. 2 above, the water contained in the solvent is separated in the water separator 22 based on the difference in specific gravity, and the separated water is directly discharged from the system through the water pipe 29. , has been discarded.

Next, a conventional dry cleaning apparatus equipped with an activated carbon solvent recovery device will be described with reference to FIG.

In the figure, 34 indicates the main body of the dry cleaner. This main body 34 corresponds to the dry cleaner described in FIG. 1 and includes a water separator 22. 35 is an inlet of the recovery air duct 19 provided in the dry cleaner main body 34, and is a fresh air intake by the damper 25. Further, 36 is a deodorizing port of the recovery air duct 19 provided in the main body 34, and is a deodorizing port of the recovery air duct 19 provided in the main body 34.
6 is a disposal port for uncondensed gas. An activated carbon solvent recovery device having the following configuration is attached to the main body 34 via the fresh air intake port 35 and the uncondensed gas disposal port 36.

That is, 37 is an activated carbon tank containing a heat storage body and activated carbon. The activated carbon tank 37 has an exhaust port 37a.
and steam piping 37b are provided in communication with each other. 38 is a drying fan that sends hot air to the activated carbon tank 37. 39 is a water-cooled condenser, and activated carbon tank 3
This is for condensing the separated gas when the solvent adhering to the activated carbon is separated by the steam or hot air sent to 7. Reference numeral 40 denotes a cool storage tank containing a built-in cool storage body, and is provided in the circulation path of the solvent 4 to the main body 34 . Reference numeral 41 denotes a refrigerator, which is provided to cool the cold storage body in the cold storage tank 40. 42 is a water separator, which includes a cold storage tank 40 and a water-cooled condenser 3.
This is to separate the liquid water condensed in step 9 and take out the solvent.

In the dry cleaning apparatus shown in FIG. 4, cleaning is performed in the same manner as described for the apparatus shown in FIG.
Water containing some solvent is discharged from the water pipe 29 of the water separator 22 to the outside of the system. On the other hand, highly concentrated solvent gas (estimated concentration 250 g/cm ³ ) is exhausted from the deodorizing port 36.
is processed as follows.

(a) First, this highly concentrated solvent gas is led to the cold storage tank 40, and is further circulated through the aero 35 and back to the main body 34. And the cold storage tank 40
In the water separator 4, the solvent gas is cooled, condensed, and liquefied.
Sent to 2. The water separator 42 separates the water contained in the condensate, and the separated solvent is discharged to the solvent tank of the main body 34, while the separated water containing some solvent is discharged to the outside of the system. Note that the refrigerator 41 cools the cold storage tank 40 before the above steps.

(b) The solvent gas reduced to a low concentration in step (a) above (estimated concentration 25 g/m ³ ) is led to the activated carbon tank 37, where the activated carbon adsorbs and removes the solvent. The air from which the solvent has been removed in this way is disposed of through the exhaust port 37a.

(c) Next, close the exhaust port 37a and close the steam pipe 37b.
Steam is caused to flow into the activated carbon tank 37, and the solvent adsorbed on the activated carbon is separated by the steam. The separated solvent-containing vapor is introduced into a water-cooled condenser 39, liquefied, and sent to a water separator 42. The water separator 42 separates the solvent and water, and the separated water is discharged outside the system.

(d) Next, open the exhaust port 37a and turn on the drying fan 38.
Warm air is sent from the activated carbon tank 37 to the activated carbon tank 37 to dry and regenerate the wet activated carbon.

As mentioned above, the dry cleaning apparatus shown in FIG. 4 uses two water separators 22 and 42, and also uses activated carbon adsorption to recover the solvent.
The water separated by the water separator is directly discharged from the system as in the case shown in FIG.

[Problem that the invention seeks to solve]

In the conventional dry cleaning apparatus described above, the water separated by the water separator based on the difference in specific gravity is discharged as is, and therefore the waste water contains a considerable amount of solvent. For example, in the case of a small container with the configuration shown in Figure 2, 10 kg of items to be washed can be washed per day.
If the test is carried out 10 times, the amount of water discharged from the water separator 22 to the outside of the system will be approximately 6 liters/day. Of these, wastewater from indirect heat distillation is _Q1 , and wastewater from direct heat distillation is _Q2.
Then, the breakdown of wastewater amount is Q ₁ = 2 liters/day,
Q ₂ = 4 liters/day, and the solvent concentration in the wastewater is as high as Q ₁ = 1000 ppm and Q ₂ = 300 ppm.

In addition, in the case of the dry cleaning apparatus shown in FIG. 4, steam is used to separate and recover the solvent adsorbed on the activated carbon, and the steam is separated and discharged by the water separator 42, so that both The amount of waste water discharged from the water separators 22, 42 is nearly two to three times that in the case of FIG.

In this way, conventional dry cleaning equipment simply discharges wastewater containing solvents,
When operated in large quantities in a concentrated manner, there was a problem of contamination of the groundwater in the area with the solvent. especially,
Recently, the problem of groundwater contamination caused by organic chlorine compounds has been emphasized, and regulatory trends have been announced by related ministries and agencies, so there is an urgent need to solve this contamination problem.

The present invention has been made to solve the above-mentioned problems as a technical subject, and aims to provide a dry cleaning device that can significantly reduce the concentration of solvent contained in waste water.

[Means for solving problems]

In order to achieve the above object, the present invention temporarily stores the wastewater discharged from the dry cleaning equipment main body or the water separator of the activated carbon solvent recovery equipment in a storage tank, and separates the solvent in the safety separator according to the difference in specific gravity. It was decided to separate and collect it. Furthermore, after the solvent has been separated by specific gravity, the wastewater is sent from the storage tank to the aeration tank, where it is aerated for a predetermined period of time to volatilize the solvent dissolved in the wastewater and further reduce the solvent concentration before it is disposed of. .

That is, the dry cleaning apparatus according to the present invention is a dry cleaning apparatus that cleans items to be washed using a solvent, and includes a waste water storage tank provided in communication with a drain port of a water separator, and a waste water storage tank provided in communication with a drain port of a water separator. A solvent recovery valve installed at the bottom,
An aeration tank connected to the wastewater storage tank via a pump, an automatic opening/closing valve for disposal provided in the aeration tank, and a control device for controlling the pump, and formed by the water separator. After the wastewater is stored in the wastewater storage tank and the solvent contained in the wastewater is separated by the difference in specific gravity and recovered from the solvent recovery valve, a predetermined amount of the remaining wastewater is sent to the aeration tank by the pump for a predetermined period of time. This system is characterized in that the aerated wastewater is disposed of outside the system through the disposal valve.

[Effect]

In the dry cleaner device according to the present invention, the waste water formed in the dry cleaner body is not disposed of as is, but is stored in the safety separator and the solvent contained in the waste water is separated and recovered based on the difference in specific gravity. The solvent is aerated inside and the solvent is removed by volatilization before being disposed of outside the system.

Therefore, the concentration of solvent in the waste water to be disposed of is significantly reduced, and the problem of solvent contamination of ground water and the like is avoided.

In addition, since aeration is carried out in the aeration tank,
There will be no problem of air pollution.

〔Example〕

FIG. 1 is an explanatory diagram showing the main parts of a dry cleaning apparatus according to an embodiment of the present invention. In this figure, the same parts as in FIG. 4 are given the same reference numerals, and their explanations will be omitted.

As shown in the figure, in this embodiment, a waste water storage tank 43 is provided which communicates with the water separator 22 of the dry cleaner main body 34 via a water pipe 29. A solvent recovery valve 48 is provided at the lower end of the bottom surface of the waste water storage tank 43. An aeration tank 44 is connected to this waste water storage tank 43 via a pump 45. The aeration tank 44 has a built-in porous ventilation body to generate warm air in the form of bubbles. Further, the aeration tank 44 is provided with an automatic opening/closing valve 49 for wastewater disposal, and the automatic opening/closing valve 49
is connected to the control box 50 so that it can be opened and closed automatically. The control box 50 is also connected to the pump 45 to control its operation. That is, the control box 50 has a built-in timer and relay for automating the device.

To explain the operation of the wastewater treatment device having the above configuration, the operation of the main body 34 causes the water separator 2 to
The waste water discharged from 2 first passes through the water pipe 29 and is stored in the waste water storage tank 43. When one day's worth of wastewater is stored in this manner, for example, a solvent such as perchlorethylene contained in the wastewater has a higher specific gravity than water, so it settles to the bottom of the wastewater storage tank 43 and is separated. That is, the storage tank 43 functions as a specific gravity difference separator. The perchlorethylene and the like thus sedimented and separated are recovered by opening the valve 48 once every few days, and are returned to the distiller 15 of the main body of the dry cleaner.

Even after the solvent is separated by specific gravity in this manner, several hundred ppm of the solvent remains dissolved in the waste water remaining in the tank 43. Therefore, the switch on the control box 50 is turned on.
By turning on and operating the pump 45,
A fixed amount of wastewater is fed from the tank 43 to the aeration tank 44. Aeration is carried out in the aeration tank 44 for a certain period of time (about one hour is sufficient), thereby resulting in wastewater containing almost no solvent. When the aeration is finished, the automatic opening/closing valve 49 for disposal automatically opens.
Dispose of purified wastewater outside the system. Thereafter, the automatic on-off valve 49 is closed, the pump 45 is operated and the waste water is sent to the aeration tank, and the above aeration and disposal process is repeated.

According to the dry cleaning apparatus of the above embodiment, by aerating a certain amount of wastewater for a certain period of time, the concentration of the solvent contained in the wastewater can be reduced and stabilized. According to the test results, by aerating wastewater that had a solvent concentration of about 200 ppm before aeration for about one hour, the solvent concentration was reduced to 0.06 ppm.

In addition, since aeration is automatically performed for a certain period of time with almost no operator intervention, erroneous operations are prevented.
The danger of erroneously disposing of dirty wastewater can be avoided.

Furthermore, since it is a continuous batch type aeration system, it is possible to process a large amount in one day with the addition of simple equipment.

In addition, in the above embodiment, the wastewater storage tank 4
If a float switch is installed in 3 and the switch detects the liquid level and operates the control circuit, automatic operation can be achieved without operating the switch in the control box 50. .

Moreover, by providing an electromagnetic valve in the aeration air source that sends air into the aeration tank 44, it becomes possible to supply air only during aeration.

〔Effect of the invention〕

As described in detail above, the dry cleaning apparatus of the present invention provides remarkable effects such as significantly reducing the concentration of solvents contained in wastewater and avoiding solvent contamination of underground water.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the main parts of a dry cleaning device according to an embodiment of the present invention, FIG. 2 is a diagram showing a schematic configuration of a conventional dry cleaning device, and FIG. Figure shown, 4th
The figure is a diagram schematically showing the configuration of a conventional dry cleaning device equipped with an activated carbon solvent recovery device. 1...door, 2...clothing, 3...solvent tank,
4...Solvent, 5...Valve, 6...Pump, 7,
9, 13, 14, 45, 46... Valve, 8...
Filter, 10... Processing tank, 11... Processing drum, 12... Button trap, 15... Distiller,
16... Juan, 17... Air cooler, 18...
Air heater, 19...Recovery air duct, 2
2, 42...Water separator, 23...Solvent piping, 24
...Clintank, 25, 26...Damper, 27
... Condenser, 28 ... Partition plate with overflow, 30 ... Steam piping, 31 ... Cooling water piping, 3
2, 33... Steam piping, 34... Dry cleaner body, 37... Activated carbon tank, 38... Drying fan,
39...Water-cooled condenser, 40...Cold storage tank, 4
1... Refrigerator, 43... Waste water storage tank, 44...
... Aeration tank, 45 ... Pump, 48 ... Solvent recovery valve, 49 ... Disposal valve, 50 ... Control box.

Claims (1)

[Claims] 1. In a dry cleaning device that cleans items to be washed using a solvent, there is provided a wastewater storage tank that is connected to a drain port of a water separator, and a solvent recovery valve that is installed at the bottom of the storage tank. ,
An aeration tank connected to the wastewater storage tank via a pump, an automatic disposal valve provided in the aeration tank, and a control device for controlling the pump, and formed by the water separator. By storing the wastewater in the wastewater storage tank, the solvent contained in the wastewater is separated by the difference in specific gravity and recovered from the solvent recovery valve, and then a predetermined amount of the remaining wastewater is sent to the aeration tank by the pump, and a predetermined amount A dry cleaning device characterized in that the time-aerated wastewater is disposed of outside the system through the disposal valve.