JPS6142546Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method and apparatus for recovering organic solvents used in dry cleaning equipment and the like.

A conventional dry cleaning apparatus is constructed as shown in FIG. 1, and the cleaning process includes a washing process, a liquid removal process, a drying process, and a deodorizing process in this order. In the washing process, the object to be washed 1 is washed with perchloroethylene, 1,1,1-trichloroethane.
Remove dirt by soaking in a highly volatile solvent such as R11R113. Furthermore, in the liquid removal step, the washing drum 2 is rotated at high speed to centrifugally separate the solvent. In the drying process, the air inside the cleaning device is circulated through the water cooler 4 and the heater 5 to the inside of the washing drum 2 by the circulation fan 3.

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

Therefore, for example, if the solvent is perchloroethylene, the concentration of the solvent in the air cannot be reduced to 250 g/m ³ or less if the cooling temperature is around 35°C.
If this continues, a strong odor will remain on the item 1 to be washed.

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

However, although the exhaust gas is diluted, it initially releases solvent gas that reaches tens of thousands of ppm, causing air pollution problems. Therefore, in order to counter this problem and to save resources by recovering solvents, a solvent adsorption tank 9 is provided through a duct 8, and the solvent gas is adsorbed to an activated carbon layer 10 provided in this tank 9, and only clean air is released into the atmosphere. There is.

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

Following the desorption process, the drying fan 14 is operated to enter a drying process to dry the activated carbon layer 10, and the activated carbon layer 10 is regenerated in preparation for the next adsorption process.

When water vapor is guided from the steam pipe 11 to the activated carbon layer 10 in the desorption process, the air in the activated carbon layer 10 is pushed out to the water separator 13 via the water-cooled condenser 12, so that the liquid level in the water separator 13 increases. There were drawbacks such as the water seal being broken by being pushed, and the water flowing out from the recovered solvent outlet 15 and risking entering the recovered solvent tank (not shown). Note that 16 indicates a drain port, and 17 indicates an air outlet.

On the other hand, in the drying process, when the drying fan 14 operates, its discharge pressure is transmitted to the water separator 13, resulting in the same problem as described above.

The present invention was developed in view of the above-mentioned drawbacks of the conventional systems. It has a condenser that guides the desorbed solvent gas, and a water separator connected to the condenser via a conduit to guide the condensed and liquefied solvent and separate it into recovered solvent and water by specific gravity,
In the middle of the conduit connecting the water separator and the condenser or the solvent adsorption tank and the condenser, a first regulating valve that is closed when a fan for drying the solvent adsorption tank is operated is installed in the water separator. According to the present invention, the solvent gas recovery device is provided with second regulating valves that communicate with the atmosphere for a predetermined period of time from the start of desorption of the solvent adsorption tank. A second regulating valve is provided that communicates the interior with the atmosphere, so the air generated from the solvent adsorption tank during the desorption process is smoothly discharged from the second regulating valve to the atmosphere through the condenser and water separator. The negative effect on the liquid level of the water separator is eliminated.

Further, when drying the solvent adsorption tank, the first regulating valve shuts off the discharge pressure from the drying fan so that it does not adversely affect the water separator, so that the liquid level in the water separator is maintained at a normal level.

Therefore, there is no risk of the water separator's water seal breaking and water entering the recovered solvent tank, and the solvent recovery accuracy is further improved, resulting in excellent effects such as a marked improvement in solvent recovery efficiency. It is something that can be played.

An embodiment of the present invention will be described below based on FIG. 2.

In the figure, 9 is a solvent adsorption tank in which the solvent gas from the washing drum (not shown) is applied to the activated carbon layer 10 via a conduit 8, and 11 is a solvent adsorption tank in which the solvent that has reached the activated carbon layer 10 is desorbed (evaporated). 14 is a drying fan for drying the activated carbon layer 10 after desorption.

12 is a condenser that is connected to the solvent adsorption tank 9 via a conduit 30 and that guides the solvent gas evaporated in the desorption process of the solvent adsorption tank 9 and condenses it to liquefy it;
13 is connected to the condenser 12 via a conduit 31 to introduce the condensed and liquefied solvent, which is separated into recovered solvent and water by specific gravity, and the recovered solvent is sent from the solvent outlet pipe 15 to a solvent tank (not shown). This is a water separator that discharges water from the discharge pipe 16 to the outside of the machine.

21 is provided in the middle of a conduit 31 connecting the condenser 12 and the water separator 13, and is automatically closed only while the drying fan 14 is operating, so that the discharge pressure from the drying fan 14 is not affected by the water separator. 13.

22 is provided facing the air chamber 23 of the water separator 13, and is automatically opened for a predetermined time (set by a timer not shown) when the activated carbon layer 10 starts to be desorbed, thereby connecting the air chamber 23 and the atmosphere. This is a second regulating valve that is communicated with the valve and discharges the air in the solvent adsorption tank 9 during the desorption process to the atmosphere so as not to adversely affect the water seal of the water separator 13.

As described above, according to this embodiment, the second regulating valve 22 is opened for a predetermined time (the first regulating valve 21 is open) when the desorption starts, so that water vapor is guided from the steam pipe 11 to the activated carbon layer 10, and the activated carbon The air in the layer 10 is smoothly discharged to the atmosphere through the water-cooled condenser 12, the first regulating valve 21, the water separator 13, and the second regulating valve 22, and the adverse effect on the liquid level in the water separator 13 is eliminated. The time set for the timer for opening the second regulating valve 22 is determined by the volume of the activated carbon layer 9, etc.
Immediately after the predetermined time has passed, the water separator 1 is closed.
This will not affect the functions of 3. In addition, the first regulating valve 21 closes immediately upon the start of drying to block the influence of the discharge pressure from the drying fan 14, so that the water separator 13 is not adversely affected.

Therefore, the liquid level in the water separator 13 is always maintained at a normal level, eliminating the risk of the water seal breaking and water entering the recovered solvent tank, which has excellent effects such as significantly improving solvent recovery efficiency. It is something that can be played.

Note that the first regulating valve 21 may be provided in the middle of the conduit 30 that connects the solvent adsorption tank 9 and the condenser 12.

Further, the second regulating valve 22 may be connected to any position as long as it communicates with the air chamber of the water separator 13.

Although the embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these embodiments, but can be modified in various ways without departing from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a conventional solvent gas recovery device, and FIG. 2 is an explanatory diagram showing an embodiment of the present invention. 9... Solvent adsorption tank, 12... Capacitor, 13
... Water separator, 21 ... First regulating valve, 22 ...
Second regulating valve.

Claims (1)

[Scope of utility model registration request] A solvent adsorption tank that adsorbs solvent gas discharged from dry cleaning equipment, etc., a condenser connected to the adsorption tank via a conduit, and a condenser that guides the solvent gas desorbed from the solvent adsorption tank, and a condenser connected to the condenser via a conduit. and a water separator that guides the condensed and liquefied solvent and separates it into recovered solvent and water by specific gravity, and the solvent adsorption tank is installed in the middle of a conduit connecting the water separator and the condenser or the solvent adsorption tank and the condenser. The water separator is provided with a first regulating valve that closes during the operating time of the fan for drying the water separator, and a second regulating valve that communicates the interior of the water separator with the atmosphere for a predetermined time from the start of desorption of the solvent adsorption tank. A solvent gas recovery device featuring: