JP3819468B2 - Condensation trap - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention condenses and recovers low-boiling component vapor in a solution containing a low-boiling liquid such as an organic solvent in a vacuum system, and reduces the amount of low-boiling component mixed in a vacuum pump used for decompression. It relates to a suitable condensation trap.
[0002]
[Prior art]
In order to prevent the organic solvent vapor from being sucked into the vacuum pump during the concentration operation in which the organic solvent in the solution is distilled under reduced pressure using an evaporator to concentrate the solution containing the organic solvent, the evaporator and the vacuum pump are It is necessary to place a condensation trap between them.
FIG. 5 illustrates a conventional condensation trap. This condensation trap is obtained by immersing a glass capacitor 1 in an antifreeze liquid 3 such as methanol or silicon oil in a trap tank 4 provided with a cooling coil 2. It is. In the cooling coil 2, a refrigerant such as chlorofluorocarbon cooled by a heat exchanger 8 attached to the refrigerator 10 is pumped by a pump 9 and circulates in the cooling coil 2 through pipes 13 and 14. ing. The glass condenser 1 is evacuated by a vacuum pump 12, and an organic solvent heated and vaporized to an appropriate temperature is introduced into the glass condenser 1 from a pipe 11, and liquefaction condensation is performed under reduced pressure. . The organic solvent-based vapor is condensed in the glass capacitor 1 and accumulates in the lower part thereof. An oil rotary vacuum pump is used as the vacuum pump 12. Further, an aspirator may be used in place of the vacuum pump 12.
[0003]
[Problems to be solved by the invention]
However, as in the conventional condensation trap described above, in the system in which the cooling condenser 2 is wound around the glass condenser 1 and cooled, the organic solvent vapor flowing in the glass condenser 1 under reduced pressure is liquefied and condensed. Since the cooling by the refrigerant is not sufficient, the organic solvent-based vapor cannot be condensed and recovered, the vaporized organic solvent is mixed into the oil of the oil rotary vacuum pump, and the oil is easily deteriorated, and the ultimate vacuum is deteriorated. For this reason, it is necessary to change the oil periodically, which disadvantageously increases the frequency of oil change. Moreover, the recovery rate of the organic solvent was poor, and it was difficult to reuse the organic solvent.
Further, when an aspirator is used instead of the vacuum pump, there is a drawback that it takes time to concentrate because the ultimate vacuum is low.
[0004]
The present invention has been made in view of the above circumstances, and aims to provide a condensing trap that efficiently recovers organic solvent vapor in a short time and prevents deterioration of oil in the vacuum pump and protects the vacuum pump. Yes.
[0005]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention is a condensation trap for condensing and collecting condensed components contained in the gas to be treated, and has a bottomed cylindrical inner tank containing a refrigerant, and a multi-stage on the outer periphery of the inner tank. Umbrella-type heat transfer fins arranged on the outside, an outer tub that accommodates them, and at least a space portion between the inner tub and the outer tub is hermetically closed, and the tip is positioned in the space portion. A lid to which an introduction pipe line and an exhaust pipe line of the gas to be treated are connected ,
A plurality of vent holes are perforated in the circumferential direction at equal intervals in the umbrella-type heat transfer fin, and the positions of the vent holes of the upper and lower umbrella-type heat transfer fins are shifted by a predetermined angle in the circumferential direction. It is a condensation trap.
The invention according to claim 2 is a condensation trap for condensing and collecting condensate components contained in the gas to be treated, and is arranged in multiple stages on the bottomed cylindrical inner tank containing the refrigerant and on the outer periphery of the inner tank. Umbrella type heat transfer fins, an outer tub that accommodates them, and at least an opening in a space between the inner tub and the outer tub, which is hermetically closed and has a tip positioned in the space. And a lid to which a gas introduction pipe and an exhaust pipe are connected,
It is a condensation trap characterized by arranging a solid filler in the inner tank.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an example of a condensation trap according to the present invention. The condensation trap 20 includes a bottomed cylindrical refrigerant tank 21 (inner tank) into which a refrigerant such as liquid nitrogen is placed, umbrella-shaped heat transfer fins 23 provided in multiple stages on the outer peripheral surface of the refrigerant tank 21, and the like. A bottomed cylindrical trap tank 22 (outer tank) for storing the liquid, a lid body 21a attached to the upper end of the trap tank 22, and steam to be treated connected to an inlet 25 provided in the lid body 21a Main pipes 26 and 61 and an exhaust pipe 62 connected to an exhaust port 27 provided in the lid 21a as main components.
As a material of the refrigerant tank 21, the trap tank 22, the umbrella-shaped heat transfer fin 23, and the lid 21a, a metal having high thermal conductivity and high corrosion resistance, for example, stainless steel such as SUS304 and SUS316, aluminum alloy, titanium, or the like is preferably used. It is done.
[0007]
At the opening of the trap tank 22, a flange 22 a is provided around the outside, and the lid 21 a is joined to the flange 22 a so that the space 22 b is formed in the trap tank 22. While being formed, the refrigerant tank 21 is stored in an airtight manner.
On the outer peripheral surface of the refrigerant tank 21, umbrella-shaped heat transfer fins 23 are arranged in multiple stages so as to partition the space 22b formed by the outer wall of the refrigerant tank 21 and the inner wall of the trap tank at equal intervals in the vertical direction. Yes.
[0008]
It is preferable that the space | interval between the front-end | tip of the said umbrella-shaped heat-transfer fin 23 ... and the inner surface of the trap tank 22 is about 1-5 mm for the following reasons.
When the distance is 1 mm or less, it is difficult to store the refrigerant tank 21 in which the umbrella-shaped heat transfer fins are formed in the condensation trap, and it is difficult to secure a flow path for allowing the solvent liquefied by the umbrella-shaped heat transfer fins to flow downward. Therefore, the interval is preferably 1 mm or more.
On the other hand, the smaller the distance between the tip of the umbrella-type heat transfer fins 23 ... and the inner surface of the trap tank 22, the more steam to be treated rises along the umbrella-type heat transfer fins, thereby effectively cooling. Therefore, the interval is preferably 5 mm or less. If this distance exceeds 5 mm, the amount of steam to be processed from the gap between the umbrella-type heat transfer fin and the side wall of the trap tank 22 will increase, and the amount of steam to be processed will be sucked into the vacuum pump 29 without liquefying or solidifying. As a result, the condensation efficiency in the trap tank 22 is lowered, and the oil of the vacuum pump is accelerated.
[0009]
The number of stages of the umbrella-type heat transfer fins 23 is not particularly limited. Moreover, it is preferable that the pitch between the steps of the umbrella-type heat transfer fins 23 is about 20 to 100 mm.
The reason why the pitch is 20 to 100 mm is that the workability in production is taken into consideration, and if the work is possible, it is preferable to shorten the pinch.
Moreover, the umbrella-type heat transfer fin 23 is provided so as to descend toward the peripheral edge of the umbrella-type heat transfer fin in order to flow the low boiling point component liquefied on the upper surface of the umbrella-type heat transfer fin to the bottom surface of the trap tank 22. That is, the angle θ formed by the umbrella-type heat transfer fin and the outer wall of the refrigerant tank may be less than 90 °, preferably 60 to 85 °.
[0010]
The umbrella-type heat transfer fin 23 is provided with a vent 23a for guiding the steam to be treated introduced into the lower part inside the trap tank 22 to the upper part inside the trap tank 22 along the umbrella-type heat transfer fin. . Since the resistance of the steam to be processed to move upward can be adjusted depending on the size of the vent 23a, it can be appropriately set so as to obtain an arbitrary rising speed.
[0011]
FIG. 2 and FIG. 3 exemplify the mode of the vent 23a formed in the umbrella-type heat transfer fin. In these drawings, 23c indicated by a dotted line indicates the position of the vent 23c in the umbrella-type heat transfer fin one step above or one step below the umbrella-type heat transfer fin 23 shown in the drawing.
As shown in FIG. 2, when the number of the vent holes 23a per umbrella-type heat transfer fin 23 is one, the position of the vent holes 23a of the upper and lower umbrella-type heat transfer fins 23 is centered in the radial direction. Preferably, each stage is alternately shifted by 180 ° in the circumferential direction so as to be opposed to each other. As a result, the contact time of the steam to be treated with the heat transfer fins and the outer surface of the refrigerant tank can be maximized, so that the steam to be treated can be efficiently cooled.
That is, as shown in FIG. 4, the flow path of the steam to be treated introduced from the introduction pipes 26 and 61 to the vicinity of the bottom surface of the trap tank 22 is formed so as to flow half a circumference along each umbrella-shaped heat transfer fin 23. can do.
[0012]
FIG. 3 shows an example in which two vent holes 23a and 23a are formed in a single umbrella-shaped heat transfer fin 23 while being shifted by 180 ° in the circumferential direction. In this case, the vent hole directly above the steam to be treated rising from below the umbrella-type heat transfer fin 23 shown in FIG. 3 is in contact with the upper surface of the umbrella-type heat transfer fin 23 or the outer peripheral surface of the refrigerant tank for the longest time. It is preferably provided at a position shifted by 90 ° in the circumferential direction. That is, the umbrella-shaped heat transfer fin of the same shape is attached to the refrigerant tank 21 in the direction rotated by 90 ° in the circumferential direction on the first stage of the umbrella-shaped heat transfer fin shown in FIG. 23c is set to a position corresponding to the middle of the vent holes 23a, 23a. Then, it is preferable that the vent holes of the upper umbrella-shaped heat transfer fins 23 are alternately and sequentially attached so that the vent holes of the upper umbrella-shaped heat transfer fins 23 are shifted by 90 ° in the circumferential direction.
Furthermore, not limited to the example shown in FIG. 2 or FIG. 3, it is also possible to provide three or more vent holes at equal intervals in one umbrella-type heat transfer fin. Even in such a case, it is preferable that the vents of the upper and lower umbrella-shaped fins are formed at locations corresponding to the middle of the vents formed for each stage.
Further, as shown in FIGS. 2 and 3, the umbrella-type heat transfer fin 23 is formed with an insertion hole 23 b for inserting an introduction pipe 26 described later.
[0013]
The lid 21a is provided with a steam inlet 25 and a steam outlet 27 so as to communicate with the inside and outside of the space 22b formed by the refrigerant tank 21, the trap tank 22 and the lid 21a. Yes.
Introductory pipes 61 and 26 for introducing the steam to be treated are connected to the steam to be treated inlet 25, so that steam to be treated such as an organic solvent can be introduced into the space 22 b through these. It has become. And the to-be-processed steam introduction pipe | tube 26 penetrates the insertion hole 23b formed in the several umbrella-shaped heat-transfer fin 23 formed in multiple stages, and guides to-be-processed steam below the lowermost-stage umbrella-type heat transfer fin. And the periphery of the introduction pipe line 26 is attached so as to be in contact with the umbrella-type heat transfer fins 23.
The processing steam exhaust port 27 is for exhausting processing steam from the space 22 b and is provided at a position facing the processing target steam introduction port 25 with respect to the center of the refrigerant tank 21. Thereby, the flow path of the steam to be treated is introduced into the space portion 22b from the steam to be treated inlet 26 through the steam to be treated inlet 25 and exhausted from the steam outlet 27 of the steam to be treated. The steam to be treated has good condensation efficiency. A pipe 62 provided with a vacuum pump 29 is connected to the processing steam exhaust port 27.
[0014]
The lid 21a is provided with a refrigerant supply port 37 and a vaporized refrigerant exhaust port 39 so as to communicate between the inside and outside of the refrigerant tank 21, and a pipe 63 and a refrigerant introduction pipe 38 are attached to the refrigerant supply port 37. A refrigerant such as liquefied nitrogen is introduced into the refrigerant tank 21 from the pipe 63, the refrigerant supply port 37, and the refrigerant introduction pipe 38, and the vaporized refrigerant can be exhausted from the vaporized refrigerant exhaust port 39.
As the refrigerant, an appropriate refrigerant can be selected depending on the condensation temperature of the low boiling point component. For example, a low-temperature liquefied gas such as liquefied nitrogen (at atmospheric pressure of −195.8 ° C.), a dry ice-alcohol refrigerant, or the like is preferably used.
Further, the lid 21a is provided with a level gauge mounting port 40 for mounting the level gauge 41. By inserting the level gauge 41 into the refrigerant tank 21 from the level gauge mounting port 40, The liquid level height of the refrigerant introduced into the refrigerant tank 21 can be measured.
The method for measuring the liquid level of the refrigerant is not particularly limited. For example, the liquid level of the refrigerant can be automatically measured from the measured value of the protrusion height from the liquid level of the liquid level gauge. . Then, a liquid level indicating controller 42 is connected to the automatic measuring liquid level meter 41, and data of the refrigerant liquid level inside the refrigerant tank 21 measured by the liquid level meter 41 is sent to the liquid level indicating controller 42. If the liquid level indicating controller 42 opens the electromagnetic valve 36 to supply the refrigerant when it falls below a predetermined height, and the electromagnetic valve 36 is closed when the predetermined refrigerant liquid level is reached, the refrigerant Can be automatically supplied.
[0015]
In addition, the refrigerant tank 21 is filled with a solid filler 35, and the cooling efficiency of the refrigerant tank and the umbrella-type heat transfer fin is improved by maintaining a high refrigerant liquid level while saving the amount of refrigerant used such as liquid nitrogen. Can be increased. Further, the use of the solid filler 35 can reduce the amount of remaining refrigerant at the end of the operation. As the solid filler 35, a spherical or columnar material made of a metal such as an aluminum alloy or iron, a ceramic such as alumina or silica, and glass is preferably used.
[0016]
The condensation trap 20 is used while being kept in the cold storage tank 24. Further, a heater 34 for heating the trap tank is provided on the outer periphery of the trap tank 22, and when the low boiling point vapor is solidified on the inner wall of the trap tank 22, this is heated and liquefied. It can be drained downward. A drain valve 32 for discharging the solvent accumulated in the trap tank 22 to the outside is provided at the bottom of the trap tank 22.
[0017]
The exhaust line 62 is connected to the vacuum pump 29. As this vacuum pump 29, a normal vacuum pump such as an oil rotary vacuum pump can be used.
The other end side of the introduction pipe line 26 is connected to the exhaust end of the rotary evaporator 50. This rotary evaporator 50 is equipped with a rotation driving means (not shown) for attaching a sample flask containing a solution to be concentrated and rotating the flask. Above this, the evaporated vapor is condensed by flowing cooling water through the internal snake pipe 51a. A water-cooled recovery trap 51 is connected, and a receiving flask for collecting the condensed solvent or the like is attached below the water-cooled recovery trap 51. The sample flask 53 is immersed in a water bath 54 and heated to a predetermined temperature. The end of the water-cooled recovery trap 51 opposite to the connection side of the rotary evaporator 50 is connected to the steam supply pipe 61, the rotary evaporator 50 is exhausted through the pipe 61, and the solvent is removed from the solution under reduced pressure. Etc. can be evaporated to concentrate the solution.
[0018]
Further, the condensation trap 20 can be configured as a portable type in addition to the stationary type as illustrated. When the condensation trap 20 is made portable, the pipes 61 and 63 may be provided with a joint having high joint strength, and the condensation trap 20 may be detachable at this joint. Further, if the trap tank 22 and the cold storage tank 24 are integrated and a vacuum insulation container is formed by evacuating the space between the trap tank outer wall and the cold storage tank inner wall, it is possible to provide a condensation trap that is highly portable and easy to carry. . Furthermore, when it is set as a portable condensation trap, it is preferable to provide the support body which supports a refrigerant tank inside a trap tank, and to raise intensity | strength.
Moreover, when setting it as a portable condensation trap, it is preferable to form the internal diameter of the trap tank 22 to about 200-400 mm.
[0019]
With the above configuration, in the condensation trap 20, the refrigerant tank 21 and the umbrella-shaped heat transfer fins 23 formed on the outer peripheral surface thereof are cooled by introducing a low-temperature refrigerant into the refrigerant tank 21. In this state, the inner wall and the space 22b of the trap tank 22 are effectively cooled by radiant heat transfer from the refrigerant tank 21 and the umbrella-shaped heat transfer fins 23 connected to the outer wall of the refrigerant tank.
[0020]
Next, an example of how to use the condensation trap 20 shown in FIGS. 1 and 2 will be described. First, a refrigerant such as liquefied nitrogen is supplied into the refrigerant tank 21 from a refrigerant source (not shown) through a refrigerant supply port 37 from a refrigerant introduction pipe 38. The liquid level in the refrigerant tank 21 is measured by the liquid level gauge 41, and the electromagnetic valve 36 is opened and closed from the liquid level indicating controller according to the measured value so that liquefied nitrogen is automatically supplied.
Next, a rotary evaporator 50 for concentrating the solution containing the organic solvent is attached to the tip of the tube 61, and the liquid to be concentrated is put into the sample flask 53. Then, the vacuum pump 29 is operated to depressurize the space 22b in the condensation trap to 1 Torr or less. If the sample flask 53 is heated in a water bath while rotating in such a state, the low boiling point component evaporates from the liquid to be concentrated containing the low boiling point component such as the solvent in the sample flask 53. A water-cooled recovery trap 51 is provided in the upper part of the rotary evaporator 50, and the low-boiling component vapor generated by flowing water through the serpentine tube 51a is cooled under reduced pressure. However, since the temperature in the water-cooled recovery trap 51 by the water-cooled serpentine tube 51a is insufficiently cooled, only a part of the low-boiling component vapor is condensed and liquefied and collected in the receiving flask 52, and most of the vapor is collected. It is introduced into the condensation trap 20 having a low cooling temperature.
[0021]
The steam to be treated introduced into the condensation trap 20 is guided below the lowermost umbrella-type heat transfer fin 23 via the steam-to-be-treated introduction pipe 26 and is first applied to the lower surface of the lowermost umbrella-shaped heat transfer fin 23 and the like. Upon contact, it is cooled rapidly and condensed. However, the outer surface of the refrigerant tank 21 and the surface of the portion near the welded portion of the umbrella-type heat transfer fin 23 connected to the refrigerant tank may be solidified.
The remaining steam to be treated that is not liquefied or solidified reaches the upper space portion 22b through the vent holes 23a of the lowermost umbrella-shaped heat transfer fins 23. The outer wall of the refrigerant tank 21 facing the space portion 22b of this step, the upper surface of the lowermost umbrella-type heat transfer fin 23, the lower surface of the second umbrella-type heat transfer fin 23 from the bottom, etc. Solidify. Further, the steam to be treated which remains without being liquefied or solidified at this stage is the second umbrella-shaped heat transfer from the bottom formed at a position shifted by 180 ° in the circumferential direction from the vent hole 23a of the lowest umbrella-shaped heat transfer fin. It moves to the upper space 22b through the vent 23a of the fin 23, and this is sequentially repeated.
[0022]
Finally, when reaching the process steam exhaust port 27 from the vent 23a of the uppermost umbrella-type heat transfer fin 23, the process steam becomes a gas that is hardly mixed with the low-boiling-point component steam, and the vacuum pump 29 functions to external the trap tank. Is exhausted. This makes it possible to maintain the performance of the vacuum pump 29 for a long time without deteriorating the oil of the vacuum pump 29. When the low boiling point component of the solution to be processed in the sample flask 53 has been evaporated, the operation of the vacuum pump 29 is stopped. Thereafter, the low-boiling components accumulated at the bottom of the trap tank 22 are collected, and then the space 22b is heated naturally or heated by a heater 34 or the like, and frost on the outer surface of the refrigerant tank 21 or the surface of the umbrella-shaped heat transfer fins 23. The low boiling point component is liquefied and stored at the bottom of the trap tank 22 and recovered from the drain valve 32.
[0023]
【Example】
A condensation trap 20 having the configuration shown in FIGS. 1 and 3 was produced.
As a trap tank, Nippon Oxygen Co., Ltd. product name Thermo Cut D6000 (inner diameter 185 mm, depth 270 mm) was used. Using SUS316 as a material, a refrigerant tank (inner diameter 110 mm, depth 220 mm), a lid, and six umbrella-shaped heat transfer fins were prepared, assembled and welded as shown in FIG. The distance between the tip of the umbrella-type heat transfer fin and the inner wall of the trap tank was 1 mm. Further, liquid nitrogen was used as a refrigerant, and spherical alumina was used as a solid filler.
Dichloromethane (540 g) was used as a liquid to be concentrated, and concentration treatment was performed using a rotary evaporator. The evaporation process is continued for 11 minutes, and after confirming that the evaporation from the sample flask has ceased, the vacuum pump is stopped, the temperature of the trap tank is naturally raised, and the solvent component condensed in the trap tank of the condensation trap is removed. As a result of weighing, the recovered amount was 540 g and 100%.
[0024]
【The invention's effect】
According to the present invention, when a solution containing an organic solvent or the like is concentrated by an evaporator, the low-boiling component vapor generated in the evaporator is converted into a refrigerant of the condensation trap by attaching the condensation trap of the present invention to a vacuum pump. It can be liquefied or solidified by bringing it into contact with the outer wall surface of the tank or umbrella-type heat transfer fins and recovered efficiently in a short time. Thereby, since the suction of the organic solvent vapor of the vacuum pump can be prevented and the oil of the vacuum pump can be prevented from being deteriorated, the performance of the vacuum pump can be maintained over a long period of time, and the vacuum pump can be protected.
In addition, one or more vent holes are formed in each of the umbrella-shaped heat transfer fins arranged in multiple stages, and the positions of the vent holes are the umbrella-shaped heat transfer fins of the steam to be treated and the outer wall surface of the solvent tank for each stage. Recovery of steam to be treated by setting the contact time to be long and / or by positioning the tip of the pipe to be treated below the lowermost umbrella-shaped heat transfer fin Efficiency can be made high and the protective effect of a vacuum pump can be heightened.
Further, if a solid filler is disposed in the inner tank, the steam to be treated can be effectively cooled with a smaller amount of refrigerant, and the economic efficiency and operability are improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of a condensation trap according to the present invention.
FIG. 2 is a diagram showing an example of vent formation in the condensation trap of the present invention.
FIG. 3 is a diagram showing another example of vent formation in the condensation trap of the present invention.
FIG. 4 is a partial cross-sectional view showing an embodiment of the condensation trap of the present invention.
FIG. 5 is a diagram showing an example of a conventional condensation trap.
[Explanation of symbols]
20 ... Condensation trap, 21 ... Inner tank (refrigerant tank), 21a ... Lid, 22 ... Outer tank (trap tank), 22b ... Space, 23 ... Umbrella type heat transfer fin, 23a ... Vent, 25... Introduction pipe (processed steam inlet), 26... Treated steam introduction pipe, 27... Exhaust pipe (process steam exhaust), 35.

Claims (2)

A condensation trap that condenses and collects a condensed component contained in the gas to be treated, which has a bottomed cylindrical inner tank that contains a refrigerant, and umbrella-shaped heat transfer fins arranged in multiple stages on the outer periphery of the inner tank, Outer tub that accommodates them, and at least an opening in a space between the inner tub and the outer tub, which is hermetically closed and has a leading end positioned in the space, and a gas introduction pipe and an exhaust pipe There a connected lid,
A plurality of vent holes are perforated in the circumferential direction at equal intervals in the umbrella-type heat transfer fin, and the positions of the vent holes of the upper and lower umbrella-type heat transfer fins are shifted by a predetermined angle in the circumferential direction. Condensation trap to be. A condensation trap that condenses and collects a condensed component contained in the gas to be treated, which has a bottomed cylindrical inner tank that contains a refrigerant, and umbrella-shaped heat transfer fins arranged in multiple stages on the outer periphery of the inner tank, Outer tub that accommodates them, and at least an opening in a space between the inner tub and the outer tub, which is hermetically closed and has a leading end positioned in the space, and a gas introduction pipe and an exhaust pipe And a lid connected to
  A condensation trap, wherein a solid filler is disposed in the inner tank.

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