JPH0742496Y2 - Solvent recovery device - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an organic solvent gas contained in exhaust gas of a coating factory or the like and a CFC gas generated from an ultrasonic cleaning machine or the like used in a semiconductor factory (for example, , R-113) and the like. Specifically, the adsorption tower provided with the gas adsorbing element is connected to a steam supply pipe for supplying heated steam for solvent desorption, and the solvent-containing gas containing the solvent desorbed from the gas adsorbing element is cooled. TECHNICAL FIELD The present invention relates to a solvent recovery device in which a condenser that liquefies by liquefaction and a specific gravity separator that separates liquefied water by specific gravity to recover a liquid solvent are connected in communication.

<Prior Art> In this type of solvent recovery apparatus, when separating the solvent from the solvent-containing gas, conventionally, the solvent-containing gas discharged from the adsorption tower is supplied to the condenser, and in the condenser,
Both water and solvent were liquefied, and the mixed liquid of the liquefied water and liquid solvent was supplied to the specific gravity separator, and the liquid was separated by specific gravity separation to separate and collect only the liquid solvent. .

The specific gravity separator was constructed as shown in the sectional view of FIG. 7 (a).

That is, the supply pipe 02 for supplying the mixed liquid of the water W liquefied in the condenser and the liquid solvent L is communicatively connected to a predetermined portion on the upper side of the peripheral portion of the casing 01.

A partition wall 03 for separating the specific gravity is provided at a position away from the connection point with the supply pipe 02, and the supply pipe above the partition wall 03 is provided.
On the 02 side, a water receiving part that collects water W by overflow
04 is attached, a drain port 05 is provided in the water receiving portion 04, while an outflow portion 06 of the liquid solvent L is provided at a position opposite to the water receiving portion 04 with respect to the partition wall 03, A mixed liquid of water W and a liquid solvent L is supplied into the casing 01, and the difference in specific gravity between the water W and the liquid solvent L is utilized to supply the water W on the upper layer side separated from the liquid solvent L to the water receiving portion 04 and The liquid solvent L separated from the water W is separated from the water W, and the liquid solvent L separated from the water W is collected from below the partition wall 03 via the outflow portion 06. When the specific gravity of the liquid solvent L is smaller than that of water, the water W is discharged from the outflow portion 06 and the liquid solvent L is discharged from the drain port 05.

<Problems to be Solved by the Invention> In the conventional configuration as described above, when heated steam is supplied in the desorption process, the air in the adsorption tower expands rapidly due to heating, and the internal pressure increases. The supply pressure of the heated steam is applied, and as a result, the pressure inside the casing 01 of the specific gravity separator rises sharply. That is,
As shown in the cross-sectional view of FIG. 7 (b), the liquid surface is pushed down, and the water W separated in the upper layer falls below the lower end of the partition wall 03, and unexpectedly the outflow portion 06 side. Flow into. Thus, there is a drawback that the liquid solvent L is recovered in the state where the water W is mixed and the recovered liquid solvent L cannot be reused.

The present invention has been made in view of such circumstances, and avoids the pressure increased with the supply of heated steam for solvent desorption from spreading to the specific gravity separator, The purpose is to be able to collect it in a state where it is well separated from water.

<Means for Solving the Problem> In order to achieve the above-mentioned object, the present invention is to connect a steam supply pipe for supplying heated steam for solvent desorption to an adsorption tower provided with an element for adsorbing gas in communication. Along with
In a solvent recovery device in which a condenser for cooling and liquefying a solvent-containing gas containing a solvent desorbed from the gas adsorbing element and a specific gravity separator for separating a liquefied water from a specific gravity to recover a liquid solvent are connected. Between the condenser and the specific gravity separator, there is provided an intermediate liquid reservoir provided with a float valve that is opened by its buoyancy when a predetermined amount of liquid or more is accumulated.

The float valve is composed of a float valve body that rises due to the buoyancy of the liquid, and a valve seat that receives and supports the float valve body at the closed position, and the float valve body is provided between the float valve body and the valve seat. A flow path through which a very small amount of liquid flows may be formed in the closed position.

<Operation> According to the configuration of the solvent recovery device of the present invention, the mixed liquid of the water and the liquid solvent liquefied in the condenser is temporarily stored in the intermediate liquid storage part, and a predetermined amount or more of the liquid is stored therein. Along with this, the float valve is opened to flow down to the gravity separator. Then, the internal pressure rises with the supply of heated steam for solvent desorption, and when the pressure is applied to the float valve, the float valve is closed and a large pressure is propagated to the specific gravity separator side. It can be avoided.

Further, by providing a flow path for flowing a very small amount of liquid even in the closed state between the float valve body forming the float valve and the valve seat, in the steady state, the fluid is stored in the intermediate liquid reservoir. A small amount of the mixed liquid is flowed. On the other hand, when a liquid of a set amount or more is accumulated, the float valve body is lifted to open the float valve and flow down to the specific gravity separator. Then, when the internal pressure rises and pressure is applied to the float valve body, the float valve body is received and supported by the valve seat at the closed position, and it is possible to prevent a large pressure from being propagated to the specific gravity separator side.

<Embodiment> Next, an embodiment of the present invention will be described in detail with reference to the drawings.

First Example FIG. 1 is a schematic configuration diagram of a solvent recovery apparatus of a first example, in which an adsorption tower 1 equipped with a gas adsorption element A made of a tubular activated carbon fiber as a filter is arranged in parallel. Installed in the lower space of each adsorption tower 1,1
Blower 3 for supplying solvent-containing gas via solenoid valve 2
And the condenser 5 and the specific gravity separator 6 are connected via the second solenoid valve 4.

A valve body 8 that is opened and closed by an air cylinder 7 is provided at the upper opening of each of the adsorption towers 1 and 1, and the valve body 8 is connected so as to communicate with the space closed by the valve body 8.
The water vapor supply pipe 10 having the electromagnetic valve 9 is connected in communication.

With the above configuration, the first to third solenoid valves 2, 2,
4,4,9,9 and valve bodies 8,8 are opened and closed in an antithetical manner,
A solvent-containing gas is supplied to one of the adsorption towers 1 to pass through the gas adsorbing element A, and the solvent is adsorbed on the gas adsorbing element A.
While adsorbing on the activated carbon fiber of No. 2, in the other adsorption tower 1, heated steam is supplied to heat and desorb the solvent adsorbed on the activated carbon fiber of the gas adsorbing element A to regenerate it.
The desorbed solvent is supplied to the specific gravity separator 6 to separate and collect the liquid solvent.

As shown in the sectional view of FIG. 2 (a), the specific gravity separator 6 has a partition wall 12 for separating the specific gravity from the space inside the casing 11.
Allows the first space S1 and the second space to communicate with each other only at the bottom.
It is configured by partitioning into the space S2.

On the first space S1 side, a liquid supply unit 13 for supplying a mixed liquid of water W liquefied in the condenser 5 and a liquid solvent L is provided at a predetermined position on the upper side of the casing 11 away from the partition wall 12. Set up.

On the other hand, on the side of the first space S1, above the partition wall 12,
A water receiving portion 14 for collecting water W by overflow is attached, and a drain port 15 is provided in the water receiving portion 14. On the other hand, an outflow portion 16 for the liquid solvent L is provided at a position on the opposite side of the water receiving portion 14 with respect to the partition wall 12, and a mixed liquid of the water W and the liquid solvent L is supplied into the casing 11 so that the water W Utilizing the difference in specific gravity from the liquid solvent L, the upper layer side water W separated from the liquid solvent L is recovered via the water receiving part 14 and the drain port 15, while the liquid solvent L separated from the water W is partitioned. It is configured to collect from below the wall 12 via the outflow portion 16.

Between the condenser 5 and the specific gravity separator 6 and the liquid supply section
An intermediate tank 17 is formed at a position adjacent to 13. The intermediate tank 17
A float valve 19 including a valve seat 19b having an opening formed in the center and a float valve body 19a having a specific gravity smaller than that of the side having a smaller specific gravity of water and solvent is provided in a communication pipe 18 connected to the condenser 5 To form the intermediate liquid reservoir 20. That is, at the time of steady solvent desorption, the mixed liquid ML of the water W and the liquid solvent L condensed and liquefied by cooling in the condenser 5 is stored in the intermediate liquid reservoir 20.
The float valve body 19a rises due to buoyancy as the stored amount exceeds a preset amount, the float valve 19 is opened and the mixed liquid ML flows down to the intermediate tank 17, and the intermediate tank 17 The specific gravity separator 6 is supplied. Float valve body
As 19a, various materials such as those made of Teflon (trademark of DuPont) can be used as long as they have corrosion resistance to a solvent and can be configured to have a smaller specific gravity than both water and the solvent.

A gas vent pipe 21 is connected to the communication pipe 18 at a position above the intermediate liquid reservoir 20, and the gas vent pipe 21 is connected to a pipe to the blower 3.

With the above configuration, when the solvent desorption is started and the internal pressure of the adsorption tower 1 is rapidly expanded due to the heating and expansion of the air in the adsorption tower 1 due to the supply of the heated steam, the pressure is increased by the float valve.
19 and pushes down the float valve body 19a so that the valve seat 19b
Then, due to the closing action of the float valve 19, the increased pressure is blocked from being transmitted to the specific gravity separator 6 side from the intermediate liquid reservoir 20. At this time, the gas in the communication pipe 18 is discharged from the degassing pipe 21, the pressure in the condenser 5 and the communication pipe 18 is released, and an insufficiently treated gas mixed with a solvent is adsorbed in the adsorption tower 1 It is designed to be returned to the side for reprocessing.

Next, the experimental results will be described.

In the embodiment described above, when air having a pressure of 400 mmH ₂ O is flowed in, the float valve 19 is closed to block the flow of air into the specific gravity separator 6 and the specific gravity separator 6 due to a sudden increase in internal pressure.
It was revealed that the pressure propagation to water was avoided, the specific gravity separation was not adversely affected, and the specific gravity separation between water and the liquid solvent was surely performed well.

Then, in this solvent recovery apparatus, when a gas mixed with Freon R113 was subjected to adsorption treatment and solvent desorption was performed by supplying heated steam, a liquid of Freon R113 that could be reused as it was without being mixed with water was recovered.

Second Embodiment FIG. 3 is a cross-sectional view of the main part of the solvent recovery apparatus of the second embodiment,
FIG. 4 is an enlarged view of a main part of FIG. 3, and FIG. 5 is an enlarged sectional view taken along line VV of FIG. 4, in which the intermediate tank 17 and the communication pipe 18 are provided with a valve seat 22. The valve seat is connected through the seat forming member 23.
An O-ring 24 for sealing is attached to 22.

Above the valve seat 22, a float valve body 25 in which a conical portion 25b is connected below the cylindrical portion 25a is provided, and the float valve 26 is constituted by the valve seat 22 and the float valve body 25.

In the conical portion 25b of the float valve body 25, four small grooves 27 extending toward the apex are provided at four positions spaced by a predetermined distance in the circumferential direction.
, And the float valve body 25 is in the closed position,
A channel for flowing a very small amount of liquid is formed between the sealing O-ring 24 and the sealing O-ring 24.

The rest of the configuration is the same as that of the first embodiment, and the explanation is omitted by giving the same drawing numbers.

With the above configuration, when the solvent is desorbed in the steady state, the water W and the liquid solvent L condensed and liquefied by cooling in the condenser 5 are liquefied.
The mixed liquid ML with is stored in the intermediate liquid reservoir 20 and the groove 27
The flow path formed by ... Is closed to allow a small amount of liquid to always flow into the intermediate tank 17. Further, when the storage amount becomes large and the storage amount becomes equal to or larger than the set amount, the float valve body 25 is lifted by the buoyancy and the float valve 26 is opened to mix the mixed liquid ML in the intermediate tank.
It flows down to 17, and is supplied from the intermediate tank 17 to the specific gravity separator 6.

In the second embodiment, the groove is provided on the valve seat 22 side, or
It may be configured to be formed on both the float valve body 25 and the valve seat 22 to form a flow path through which a minute amount of liquid flows. The groove 27
Is not limited to the four positions illustrated, but can be selected as appropriate.

Third Embodiment FIG. 6 is a cross-sectional view of the essential parts of a third embodiment of the solvent recovery apparatus. The third embodiment differs from the second embodiment in the following points.

That is, the connecting tubular portion 11a is provided so as to project from the top plate portion of the casing 11 away from the partition wall 12, and the communicating pipe 18 is connected to the connecting tubular portion 11a via the valve seat forming member 23. The intermediate tank 17 in the second embodiment is omitted.

The other structure is the same as that of the second embodiment, and the explanation is omitted by giving the same drawing numbers.

As the solvent recovery device of the present invention, as in the above embodiment,
The present invention is not limited to the one in which two adsorption towers 1 are provided and the liquid solvent is continuously collected, but the one in which the liquid solvent is intermittently collected can be applied.

The solvent recovery device of the present invention is used as a filter for air purifiers and air conditioners to remove smoke and odorous substances, to control humidity, and to recover organic solvents in chemical plants and cleaning industries. Applicable to

<Effect of Device> As is clear from the above description, according to the solvent recovery device of the present invention, the pressure increased with the supply of heated steam for solvent desorption is propagated to the specific gravity separator side. Since it can be avoided by the float valve, in the specific gravity separator, it is possible to surely prevent the water separated in the upper layer side from being pushed down, and accidentally flowing into the outlet side of the liquid solvent below it, and the liquid solvent as water. It can be recovered in a well separated state, and a reusable liquid solvent can be surely obtained.

In addition, if it is configured so that the mixed liquid stored in the intermediate liquid reservoir is made to flow in minute amounts in the steady state, the float valve can be operated only when a set amount of liquid is accumulated, like a general float valve. Compared with the case of opening and flowing a set amount of liquid intermittently to the specific gravity separator side, the frequency of the float valve opening can be reduced, and a large amount of liquid can be prevented from suddenly flowing into the specific gravity separator side. As a result, the liquid can be gently flown down to the specific gravity separator side, without disturbing the liquid in the specific gravity separator, and the specific gravity separation in a steady state can be more favorably performed. In addition, when the set amount of liquid is accumulated, the liquid easily flows under the float valve body due to the flow path, the float valve body can be lifted well, and the accumulated liquid can be smoothly flowed.

[Brief description of drawings]

The drawings show an embodiment of a solvent recovery apparatus according to the present invention, and FIG. 1 is a schematic configuration diagram of a first embodiment of the solvent recovery apparatus, and FIG.
FIG. 4 is a cross-sectional view of the main part, FIG. 3 is a cross-sectional view of the main part of the second embodiment of the solvent recovery apparatus, and FIG. 4 is an enlarged view of the main part of FIG.
FIG. 5 is an enlarged sectional view taken along line VV of FIG. 4, FIG. 6 is a sectional view of an essential part of a third embodiment of the solvent recovery apparatus, and FIG. 7 is a sectional view of a conventional specific gravity separator. It is a figure. 1 …… Adsorption tower 5 …… Condenser 6 …… Specific gravity separator 10 …… Steam supply pipe 19,26 …… Float valve 19a, 25 …… Float valve body 19b, 22 …… Valve seat 20 …… Intermediate liquid reservoir Part 27: Groove (flow path) A: Gas adsorption element

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Yasuo Matsushita, 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka, Osaka Tsuruki Co., Ltd. (72) Tetsuya Takemoto, 4 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Chome 1-2 Osaka Kasha Co., Ltd. (72) Inventor Harukawa Yamaguchi 115-8-A-316 Fushiya-cho, Izumi City, Osaka Prefecture (72) Inventor Hitoshi Sakai 568 Akihacho, Totsuka-ku, Yokohama City, Kanagawa Prefecture Stock Association Asahi Works Yokohama Factory (72) Inventor Akio Ando 568 Akiba-cho, Totsuka-ku, Yokohama-shi, Kanagawa Stock Company Asahi Works Yokohama Factory (56) Reference JP-A-51-16182 (JP, A)

Claims (2)

[Scope of utility model registration request] 1. An adsorption tower provided with a gas adsorption element,
A steam supply pipe for supplying heated steam for solvent desorption is connected and connected, and a condenser for cooling and liquefying a solvent-containing gas containing a solvent desorbed from the gas adsorption element, and a specific gravity separation of liquefied water. Is a solvent recovery device in which a specific gravity separator for recovering a liquid solvent is connected in communication between the condenser and the specific gravity separator, and a float that is opened by its buoyancy when more than a set amount of liquid is accumulated. A solvent recovery device comprising an intermediate liquid reservoir provided with a valve. 2. The float valve according to claim 1,
A float valve body that rises due to the buoyancy of the liquid, and a valve seat that receives and supports the float valve body at the closed position, and the float valve body closes between the float valve body and the valve seat. A solvent recovery device that has a flow path that allows a small amount of liquid to flow in the position.