JPH0710716Y2 - Solvent recovery device for dry cleaning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a solvent recovery device for a dry cleaning device using an organic solvent such as perchlorethylene, 1,1,1-trichloroethane, and R11, R113.

[Conventional technology]

Conventionally, a dry cleaning device is configured as shown in FIG. 2, and the cleaning process includes a cleaning process, a liquid removing process,
The drying process and the deodorizing process are performed in sequence.

In the washing process, the item to be washed 1 is perchlorethylene, 1,1,1
-Immerse in a highly volatile solvent such as trichloroethane, R11 and R113 to remove dirt. Further, in the liquid removing step, the washing drum 2 is rotated at high speed to centrifuge the solvent. In the drying process, the air in the cleaning device is circulated into the washing drum 2 by the circulation fan 3 through the water-cooling cooler 4 and the heater 5.

That is, the temperature of the air is raised by the heater 5 to evaporate the solvent adhering to the object to be washed 1, and the evaporated solvent gas is guided to the water-cooled cooler 4 to be cooled to about 32 to 35 ° C. Then, the solvent gas is condensed and liquefied and recovered, but the solvent gas contained in the air is more removed as the cooling temperature is lower due to the saturation concentration.

Therefore, for example, when the solvent is perchlorethylene, the concentration of the solvent contained in the air is 25 when the cooling temperature is about 35 ° C.
It cannot be less than 0g / m ^3, and if it is left as it is 1
A strong odor remains.

Therefore, in the deodorizing step, in order to remove the odor and cool the article to be washed 1, the fresh air air damper 6 is opened to take in outside air, and this is brought into contact with the article to be washed 1 to dilute the solvent gas concentration. , Is discharged from the exhaust damper 7 to the outside of the machine.

Although this exhaust gas is diluted, solvent gas of tens of thousands ppm is discharged in the initial stage, which causes a problem of air pollution. For this reason, a solvent adsorption tank 9 is provided through the duct 8 for the purpose of countermeasures and resource saving by solvent recovery, and the solvent gas is adsorbed by the activated carbon tank 10 provided in the tank 9 so that only clean air is discharged from the exhaust damper 17. It is released into the atmosphere.

In this solvent adsorption tank 9, when the activated carbon reaches saturation with the adsorbed solvent gas, steam is sprayed onto the activated carbon from the steam pipe 11 to evaporate the solvent and perform so-called desorption. The evaporated solvent gas is guided to the water-cooled condenser 12, condensed and liquefied, and separated by the water separator 13 into the recovered solvent and water and recovered.

Following the desorption process, the dry fan 14 is activated to activate the activated carbon layer 10
Then, the activated carbon layer 10 is regenerated to prepare for the next adsorption step.

[Problems to be solved by the device]

After desorbing the activated carbon in the adsorption tank with steam and then drying the activated carbon with a drying fan, the space near the condenser in the activated carbon layer is filled with the solvent gas evaporated from the desorption due to the desorption. Is heated by steam and does not have the ability to adsorb solvent gas, so the solvent gas is released into the atmosphere supplied from the drying fan at the initial stage of drying the activated carbon, so a high concentration of solvent gas is released into the atmosphere by so-called initial breakthrough. May be

In view of the above-mentioned state of the art, the present invention is to provide a solvent recovery device for a dry cleaning device that does not have the risk of discharging solvent vapor accompanying drying air to the atmosphere.

[Means for Solving the Problems]

The present invention is to communicate with a dry cleaning device, an activated carbon adsorption tank for collecting solvent gas by activated carbon, an exhaust damper for discharging the air cleaned in the activated carbon adsorption tank, and a desorption steam for the activated carbon adsorption tank. A steam pipe, a condenser for cooling the solvent gas-containing steam discharged from the activated carbon adsorption tank, a water separator for separating the solvent and water in communication with the condenser, and a drying fan for supplying drying air to the desorbed activated carbon adsorption tank. In the solvent recovery apparatus configured as described above, a suction fan that communicates with the condenser to suck the solvent gas-containing air, an air tank that communicates with the suction fan through a suction pipe to store the solvent gas-containing air, and the air tank are provided. A solvent recovery device for a dry cleaning device, wherein a discharge pipe communicating with a drying fan is additionally provided.

[Action]

According to the device of the present invention, after desorption of the activated carbon, the solvent gas filled in the activated carbon tank at the beginning of the drying process is sucked by the fan, and the sucked solvent gas is temporarily stored in the air tank. When the solvent gas in the activated carbon tank is exhausted, the activated carbon is dried with a drying fan, and at the same time, the solvent gas-containing air stored in the air tank is fed into the adsorption tank with the drying fan to adsorb the solvent gas to the activated carbon.

Guidance on air pollution is given by the Pollution Control Ordinance. For example, in Kanagawa prefecture, exhaust gas concentration of perchlorethylene 50
It is below ppm. Conventionally, tens of thousands of ppm of solvent gas was released to the atmosphere at the beginning of drying, but the device of the present invention can prevent this.

〔Example〕

 An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, a suction pipe 22 is provided in the condenser 12 in the solvent recovery device so that the solvent adsorption tank 9 can be suctioned through the condenser 12 by the suction fan 20. The exhaust side of is connected to the air tank 21 through the same pipe 22. The air tank 21 is preferably made of a stretchable material so that it can store the sucked solvent gas.

Provide a discharge pipe 23 on the exhaust side of the air tank 21 to
When the valve 14 is activated, the solvent gas in the air tank 21 can be sucked and discharged together with the outside air.

During the deodorizing process of a dry cleaning device (not shown), a high-concentration solvent gas is exhausted from the dry cleaning device and guided to the solvent adsorption tank 9 through the duct 8. The high-concentration solvent gas is adsorbed on the activated carbon layer 10, and the air containing no solvent gas is released from the exhaust damper 17 to the atmosphere.

In the solvent adsorption tank 9, when the activated carbon reaches saturation with the adsorbed solvent gas, water vapor is sprayed from the steam pipe 11 to the activated carbon to evaporate the solvent and perform desorption. The evaporated solvent gas is guided to a water-cooled condenser 12, condensed and liquefied, and a water separator 13
It is separated into a solvent and water for recovery. At the end of the desorption process, the space near the condenser 12 in the solvent adsorption tank 9 and the activated carbon layer are filled with desorption vapor and solvent gas. Further, since the activated carbon in the activated carbon layer 10 is also desorbed, it is heated by steam and has no ability to adsorb solvent gas.

After desorption, in order not to release the solvent gas filled in the solvent adsorption tank 9 to the atmosphere, the suction fan 20 is operated, the exhaust damper 17 is opened, and the solvent gas in the solvent adsorption tank 9 is exhausted while taking in the outside air. , Or the suction fan via the condenser 12 until the upper part of the activated carbon recovers the adsorption capacity.
Aspirate at 20. Since the solvent gas exhausted from the suction fan 20 passes through the condenser 12, it has a low concentration at a low temperature. This low-temperature, low-concentration solvent gas is transferred to the air tank 21 through the suction pipe 22 and stored in the air tank 21. Next, the suction fan 20 is stopped, an automatic valve (not shown) provided on the inlet side of the air tank 21 is closed, and the drying fan 14 is immediately activated to enter the drying step of drying the activated carbon layer 10. Reproduce.

Since there is no solvent gas in the solvent adsorption tank 9 at the beginning of this drying process, or because the upper part of the activated carbon 10 has recovered its adsorption capacity, the exhaust damper 17 does not discharge high-concentration solvent gas and it is dried. It Further, since the discharge pipe 23 connected from the exhaust side of the air tank 21 is provided on the suction side of the drying fan 14, the solvent gas stored in the air tank 21 during the drying process is sucked and adsorbed on the activated carbon layer 10, 21 shrinks and prepares for the next step. After this drying process, activated carbon layer
10 is regenerated to prepare for the next adsorption step.

If an automatic valve (not shown) is provided in the pipe 23 and the automatic valve is opened only at the end of the drying process, the solvent gas can be more efficiently adsorbed to the activated carbon layer 10. Further, it is practical to provide an automatic valve (not shown) between the condenser 12 and the suction fan 20 which is closed during the attachment / detachment. Drying the activated carbon layer 10
This is performed by opening an intake damper (not shown) provided in the fan 14 and operating the fan 14 to take in the atmosphere.

[Effect of device]

After desorption of the activated carbon, the solvent gas and vapor filled in the solvent adsorption layer are sucked by the fan through the condenser, and when the solvent gas in the solvent adsorption layer is exhausted, the drying process starts, so there is no air pollution due to initial breakthrough.

Further, the solvent gas sucked by the fan is once stored in the air tank, and the stored solvent gas is not adsorbed to the activated carbon layer during the drying process or at the end of the drying process and is not released to the atmosphere.

[Brief description of drawings]

FIG. 1 is a schematic view of a solvent recovery apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic view of one mode of a conventional solvent recovery apparatus. 1 ... Washed item, 2 ... Washing drum, 3 ... Circulating fan,
4 ... Water-cooled cooler, 5 ... Heater, 6 ... Fresh air damper, 7 ... Exhaust damper, 8 ... Duct, 9 ...
Solvent adsorption tank, 10 …… Activated carbon tank, 11 …… Steam piping, 12 ……
Water-cooled condenser, 13 ... water separator, 14 ... drying fan,
17 …… Exhaust damper, 20 …… Juan, 21 …… Air tank,
22 …… Suction piping, 23 …… Discharge piping

Claims (1)

[Scope of utility model registration request] 1. An activated carbon adsorption tank which communicates with a dry cleaning device to collect solvent gas by activated carbon, an exhaust damper which discharges air cleaned in the activated carbon adsorption tank, and a steam which supplies desorption steam to the activated carbon adsorption tank. Consists of a pipe, a condenser for cooling the solvent gas-containing vapor discharged from the activated carbon adsorption tank, a water separator for separating the solvent and water communicating with the condenser, and a drying fan for supplying drying air to the desorbed activated carbon adsorption tank. In the solvent recovery apparatus described above, a suction fan that communicates with the condenser to suck the solvent gas-containing air, an air tank that communicates with the suction fan via a suction pipe to store the solvent gas-containing air, and the air tank with the drying fan. A solvent recovery device for a dry cleaning device, characterized in that a communicating discharge pipe is additionally provided.