JP2007119550A - Apparatus for recovering solvent, method for recovering solvent and method for separating polymer and solvent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new apparatus for recovering a solvent from a solution comprising a polymer and the solvent dissolving the polymer. <P>SOLUTION: This apparatus for recovering the solvent from the solution comprising the polymer and the solvent dissolving the polymer comprises a solution-storing portion, a solution film-forming portion, a solution film-drying portion, a solution film-peeling portion a solution film-conveying portion, and a solvent-recovering portion. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solvent recovery apparatus, a recovery method, and a polymer and solvent separation method. More particularly, the present invention relates to an apparatus and method for recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved.

  Optical polymer films such as optical polycarbonate films that require high performance and quality uniformity are often produced by a solution casting method. In the case of polycarbonate, methylene chloride is generally used as a solvent, and a solution in which the concentration of polycarbonate is dissolved in the solvent by about 10 to 30% by weight is generally used.

  In the production of such a polymer film for optical use, the sophistication of so-called brand change (brand change) such as change of the kind of polymer formed into a solution, change of concentration, etc. is increasing due to sophistication of required characteristics. At the time of name change, for example, even a polycarbonate may be formed by changing the solution concentration with a polycarbonate homopolymer, or may be formed by changing the solution type from a polycarbonate homopolymer to various copolymer polycarbonates. For example, when replacing the remaining solution of the solution used for film formation up to now and the solution used for film formation at the time of inscription, the solutions are mixed with each other in a transport system to produce a solution with changed characteristics. Is difficult to avoid. Even when the same kind of polycarbonate solution is mixed with different concentrations, die-striped or wrinkled surface defects are likely to occur in the film formed. In order to avoid such a problem, it is necessary to thoroughly clean the piping using the pre-used solution and sufficiently replace it with a new solvent.

  In addition, a large amount of excess polycarbonate solution may be generated at the time of change such as operation stoppage. For example, such a solution is stored for re-use by interrupting film formation. In that case, it is stored in a spare solution tank, or in a small amount, it is usually stored in a SUS drum or a plastic tank. . However, these solutions may change the properties of the solution during storage, for example, the concentration of the solution, or the polycarbonate may recrystallize in the solution, making them difficult to use again and eventually being discarded outside the system. In some cases, it may be necessary.

  As described above, in solution casting, a polymer solution may remain at the interruption or termination of film formation, or a large amount of solution in which a polymer is dissolved in a solvent may be generated by washing a process (especially in a pipe). Not a few.

As a prior art, for example, Patent Document 1 discloses a method for recycling foamed polystyrene. In this method, the solvent of styrene foam, limonene or methylene chloride is kneaded with a vent port, the solvent is devolatilized, melt extruded as polystyrene, regenerated into pellets, and the devolatilized solvent is heated. It is a method of condensing and collecting with an exchanger. However, such a method has a concern that the apparatus becomes large and the polymer resin is thermally deteriorated because it includes a melt extrusion process. As another method, for example, a method in which a polycarbonate solution is mixed with methylene chloride, for example, an alcohol or water to separate polycarbonate and methylene chloride can be considered. This is not practical because it requires a more complicated process for handling the solution.
JP 2001-146531 A

An object of the present invention is to provide a novel apparatus for recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved.
Another object of the present invention is to provide a novel method for recovering a solvent and a polymer from a solution containing the polymer and a solvent in which the polymer is dissolved.
A further object of the present invention is to provide a novel method for separating a polymer and a solvent from a solution comprising a polymer and a solvent in which the polymer is dissolved.

  The present inventors separate a polymer and a solvent as a solute from a viscous solution in which a polymer such as polycarbonate is dissolved without using a large-scale facility by a simple method (apparatus), regenerate and reuse. The method was examined.

  In particular, efforts were made to separate and recover the polymer and the solvent without degrading the polymer and the solvent from the high-viscosity polymer solution without generating polymer debris, solvent and their decomposition products as much as possible. And, there is no need to use a high temperature to melt the polymer, and by taking out the polymer in the form of a film, the polymer and the solvent are separated, the solvent is recovered, and not only the solvent but also the polymer is recovered. The present invention has been reached.

That is, the present invention is as follows.
[1] An apparatus for recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved, the solution storage tank part, the liquid film forming part, the liquid film drying part, the liquid film peeling part, the liquid film transporting part, And a solvent recovery unit. A solvent recovery device (hereinafter referred to as a recovery device of the present invention).
[2] The above-described collection device, wherein the liquid film forming unit includes a rotating body for contacting the solution.
[3] The above-described recovery device, wherein the solvent recovery unit includes a condensing unit that captures the solvent as a liquid.
[4] The above-described recovery device in a substantially sealed space.
[5] The above recovery apparatus, wherein the polymer is an aromatic polycarbonate and the solvent is methylene chloride.
[6] A method of recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved,
(1) A solution is brought into contact with a support to form a liquid film on the support,
(2) heating the liquid film;
(3) Next, the liquid film is peeled off from the support,
(4) The peeled liquid film is conveyed and taken out as a film,
(5) On the other hand, the solvent evaporated by the heating is captured by cooling and recovered.
A solvent recovery method (hereinafter referred to as the recovery method of the present invention).
[7] The recovery method described above, wherein the support is a rotating body.
[8] The recovery method described above, which is performed in a substantially sealed space.
[9] The above recovery method, wherein the polymer is an aromatic polycarbonate and the solvent is methylene chloride.
[10] A method of separating a polymer and a solvent from a solution comprising a polymer and a solvent in which the polymer is dissolved,
(1) A solution is brought into contact with a support to form a liquid film on the support,
(2) heating the liquid film;
(3) Next, the solvent evaporated by the heating is cooled and condensed.
A method for separating a polymer and a solvent (hereinafter, referred to as a separation method of the present invention).
[11] The separation method described above, wherein the support is a rotating body.
[12] The separation method described above, which is performed in a substantially sealed space.
[13] The separation method described above, wherein the polymer is an aromatic polycarbonate and the solvent is methylene chloride.

  With the recovery device, recovery method and separation method of the present invention, the polymer and solvent are efficiently separated and recovered from a solution in which a polymer such as polycarbonate is dissolved in a solvent such as methylene chloride at a relatively low temperature and with small equipment. can do. Since the polymer and the solvent are basically not deteriorated from the state of the original raw material, they can be effectively reused without waste. Since it is not a relatively high temperature operation, the outer periphery of the recovery device can be made of a chemical-resistant and heat-resistant transparent polymer resin material. In addition, the entire apparatus can be covered with such material many times. In this way, if it is used, the operation status of the inside device can be understood from the outside, and it becomes easy to deal with troubles, etc., and it is possible to prevent the solvent from escaping to the outside due to some trouble.

Hereinafter, the recovery device of the present invention will be described.
The recovery device of the present invention is a device that separates and recovers a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved. The solution storage unit, the liquid film forming unit, the liquid film drying unit, the liquid film peeling unit, A liquid film transport unit and a solvent recovery unit are included.

  Here, the polymer is determined by a combination with a solvent capable of dissolving the polymer. However, in consideration of solubility, the polymer is basically a thermoplastic polymer that is basically amorphous. Examples thereof include aromatic polycarbonate, polyarylate, cycloolefin copolymer (amorphous polyolefin), polyether sulfone and the like. Two or more kinds of these polymers may be used, but if the polymer is recovered and reused, it is better to use one kind of polymer if possible.

  The solvent needs to be capable of dissolving the polymer. For example, when the polymer is an aromatic polycarbonate, examples of the solvent include methylene chloride and 1,3-dioxolane. In the case of polyarylate, methylene chloride can be exemplified. In the case of amorphous polyolefin, xylene and toluene can be exemplified. Of these, in the present invention, it is preferable to use a solvent whose boiling point is not too high (for example, the boiling point is 60 ° C. or lower, preferably 20 ° C. to 60 ° C.), and the recovery apparatus can be small in equipment, and the solvent can be recovered. It is preferable because of its high efficiency. Two or more kinds of these solvents may be used. However, if the solvent is recovered with high efficiency and reused as a single substance, one kind of solvent is better if possible.

  The concentration of the polymer in the solution in which the above polymer is dissolved in a solvent cannot be generally specified depending on the solubility of the solvent used, the molecular weight of the polymer, the structure of the repeating unit, etc., but it is important that a liquid film can be formed as described later. Usually, it is in the range of 10 to 30% by weight. For example, when the polymer is an aromatic polycarbonate and the solvent is methylene chloride, the polymer concentration in the solution is preferably in the range of 15 to 25% by weight.

  The solution containing the polymer and the solvent may contain other components such as a plasticizer, a lubricant, a heat stabilizer, and a weathering agent. However, in order to separate and recover a highly pure polymer from such a solution, it is preferable that such other components do not exist. In particular, in order to apply the recovered polymer to optical uses where high transparency is required, it is preferable that no other component is contained.

In the present invention, the solvent is separated from the solution by using an apparatus including a solution storage section, a liquid film forming section, a liquid film drying section, a liquid film peeling section, a liquid film transport section, and a solvent recovery section. And collect.
The solution storage tank is a part for storing or storing the solution temporarily or for a long time in order to form a liquid film in the liquid film forming section, and is a so-called solution tank. Such a solution tank should be able to keep the temperature of the solution constant, and may be equipped with a device capable of stirring in order to make the concentration of the solution uniform. It is made of a material that is not corroded or dissolved by the solvent.

The solution in the solution storage tank is then turned into a liquid film at the liquid film forming section.
At this time, the solution is carried to the liquid film forming unit directly from the solution storage unit or through a connecting tube.
The liquid film forming part is a part where the solution is turned into a liquid film to form a film-like material. The liquid film forming unit has a support for forming a film-like material. As the support, a flat plate such as a metal or plastic film or a rotating body such as a drum can be used.

When the solution is discharged at a rate of 1 m / min, for example, a 20 wt% solution (calculated density is 1.33 g / cm ³ ) as a 1 mm thick and 1 m wide liquid film to the liquid film forming portion. The amount discharged is 1.330 kg / min (in this case, polycarbonate is 0.266 Kg / min, methylene chloride is 1.064 Kg / min), spread on the support, A liquid film containing is formed.

  This liquid film is then dried in a liquid film drying section to evaporate the solvent and reduce the amount of solvent in the liquid film. The liquid film drying section is disposed between the liquid film forming section and the liquid film peeling section. The liquid film drying may be performed on a part of the support, or may be continuously performed after the liquid film is peeled off from the support in the liquid film peeling portion. The liquid film can be dried by, for example, blowing warm air with a drier or the like, reducing the atmosphere, or combining these. The drying temperature can be appropriately set depending on the solvent used. It can be carried out at a temperature near or slightly higher than the boiling point of the solvent. For example, when methylene chloride is used as a solvent, the range of 30 to 60 ° C. is preferable.

The solvent contained in the liquid film dried by the liquid film drying unit evaporates and vaporizes, and is collected by the solvent recovery unit. As a collecting method, for example, a method of cooling and liquefying is simple.
The liquid film dried in the liquid film drying part is pulled away from the support in the liquid film peeling part. The content of the solvent in the liquid film at this time is preferably such that the liquid film has a certain degree of self-sustainability. For example, when the polymer is 100, it is 10 to 20% by weight. The peeled liquid film is further dried in a liquid film drying section as necessary.

  The liquid film peeled off at the liquid film peeling part is transported by the liquid film transporting part, and is recovered as a film after the solvent in the liquid film is substantially not contained or has a desired content. As the liquid film transport unit, a known one that normally transports a film can be used, and examples thereof include a transport roll and a nip roll.

  In the present invention, it is preferable that the above operation is performed in one apparatus, and the apparatus is substantially hermetically sealed. That is, the solution storage part, the liquid film forming part, the liquid film drying part, the liquid film peeling part, the liquid film transporting part, and the solvent recovery part are arranged in a substantially sealed space, so that the solvent is brought into the atmosphere. It can be recovered without being released. The term “substantially” refers to the case where such a portion is not structurally sealed when the film finally obtained after being separated from the solvent is taken out of the collecting apparatus (outside the sealed space).

Hereinafter, the present invention will be described in detail using specific examples with reference to the drawings, but the present invention is not limited thereto.
In the following, a case where polycarbonate is used as a polymer and methylene chloride is used as a solvent will be described.

FIG. 1 shows an example of an overall schematic diagram of the apparatus of the present invention. In the figure, reference numeral 1 denotes an outline of the apparatus of the present invention surrounded by a dotted line. In this figure, the portion surrounded by a dotted line is the recovery device of the present invention.
A polycarbonate methylene chloride solution for separation and recovery is poured into the solution tank 2, and in order to keep this liquid level as constant as possible, it is connected by a communication pipe system with a larger reservoir tank 100 or the liquid level. Devise a meter to keep the height constant. In the solution tank 2, if the evaporation of the solvent is accelerated, the tank is cooled by the latent heat of vaporization. Therefore, it is preferable to heat from the outside of the tank so that the temperature does not decrease too much. In order to prevent the methylene chloride from evaporating from the liquid surface, the upper liquid surface of the tank is preferably cut off from the upper atmosphere by placing a partition wall 3. In this way, the warm air 4 from above prevents the liquid surface from drying and skinning. The temperature of the warm air is preferably room temperature to 80 ° C.

  Further, the inner wall of the tank (recovery device or device 1) may be structured to be cooled and condensed when the vapor of methylene chloride comes into contact, and the condensed liquid can flow down through the inner wall. It is preferable that the solution concentration of the polycarbonate used is 10 to 30% by weight and the viscosity is several thousand centipoise to several tens of thousands centipoise. If the solution viscosity is about this level, it is easy to pump the solution by attaching a solution film from the solution surface 5 to the drum surface 6. If necessary, the surface of the drum for pumping the solution is coated with a chemical-resistant resin or a fluorine-based resin so that the semi-dried polycarbonate film (liquid film) can be easily separated from the roll. To do. Also, the surface of the rolls 6 to 8 is hard chrome plated, and then the surface is roughened by sandblasting to help the liquid film easily separate from the roll surface. It is necessary to devise such as using drums and rolls and parts for rotating the drums and rolls coated with methylene chloride-resistant resin on the surface so as not to come into contact with hydrogen chloride as much as possible. It is desirable to use a polymer material that is infiltrated by methylene chloride or insoluble in methylene chloride as the surrounding material, but it is more preferable because each roll surface is also resistant to corrosion if methylene chloride-resistant plastic coating is applied. . This is because even at a relatively low temperature such as room temperature, methylene chloride gradually generates hydrogen chloride and slowly corrodes metals.

  The thickness of the liquid film pumped and formed at this time is preferably 100 μm to several hundreds of μm in order to evaporate methylene chloride from the liquid film. The drum 6 is heated from the inside at a temperature of 40 ° C. or more at the lowest. This temperature is 60 ° C. or less at the highest, and when water exceeds 60 ° C. This is because water reacts with methylene chloride and hydrogen chloride is easily generated. If the heating temperature is too low, it is difficult to efficiently evaporate methylene chloride from the film. The diameter of the drum 6 is preferably about 2000 mm and a width of about 500 mm in consideration of the thickness of the liquid film to be pumped and the time for drying it. Heating from the inside of the drum may be performed by using hot air of 50 to 55 ° C. or by flowing a heat medium inside. The peripheral speed of the drum is about 1 m / min to several m / min. After the liquid film is brought into contact with the drum 6 about 3/4 round, the liquid film is peeled off from the drum as a film through a take-off roll 7, and then taken from both sides of the film by using hot air blowing nozzles 4 or the like. Dry hot air is blown to dry the film while transporting it to the next transport roll 8. The temperature of the warm air at this time is preferably about 80 ° C. or less. The temperature of the warm air may be appropriately changed between immediately after peeling and after the drying has progressed.

  In addition, when the hot film is blown and dried when the liquid film before peeling is on the drum, the temperature and the air volume of the hot air may be appropriately controlled and set. A preferred hot air temperature range is 40-60 ° C.

  The film is further wound around a transport roll 9 and taken out as a film from the drying chamber 1 (preferably the drying chamber 1 is the recovery device 1), and then pulverized by a pulverizer to create a flake. This flake can be dissolved in methylene chloride and reused. Note that the amount of residual methylene chloride in the film before flaking is 15% by weight or less. In many cases, the surfaces adhere to each other when the films are kept in contact with each other. Therefore, in the present invention, the residual methylene chloride of the film before pulverization is preferably 15% by weight or less, more preferably 12% by weight or less.

  On the other hand, gaseous methylene chloride mixed with air separated from the film is cooled by a cooling plate (condensing unit) 10 as a solvent recovery unit, liquefied, and aerated layer filled with clean water through a conduit 11 (storage tank 101). The hydrogen chloride produced by the reaction between water and methylene chloride is also dissolved in the water. Thereafter, the mixture of water and methylene chloride is allowed to stand in the static tank 102 and separated by the difference in density of methylene chloride and water (because methylene chloride is heavy, the lower layer and the aqueous layer are the upper surface).

  In addition, air mixed with methylene chloride in the apparatus of the present invention is sent to an activated carbon type adsorption tank 103 by pneumatic transportation and separated, desorbed with water vapor, sent to an aeration tank, and treated in the same manner as the condensed liquid. The cooling plate (condensing unit) 10 includes a cooling plate 12 for cooling and liquefying the evaporated methylene chloride. The cooling plate 12 may be structured to be cooled from the upper side or the inner side with water or the like. In addition, a water film may flow down on the outside of the outer wall of the recovery device 1 to cool it. The methylene chloride condensed on the cooling plate (condensing part) 10 and the inner wall of the recovery device 1 flows down this wall surface, enters the basket 13 and is sent to the next process. Since the supernatant water in the stationary tank 102 contains a small amount of hydrochloric acid, it is neutralized with an alkali and drained. Thus, hydrogen chloride produced by reaction with water at high temperature can be removed into an aqueous system. Further, methylene chloride is dehydrated in a dehydration tank 104 having a mechanism of dehydrating with a molecular sieve, which is the next step, stored in a solvent tank (not shown), and reused.

In the case where one or more polymers in the solution are mixed, they can be recovered as a film and then depolymerized to be recovered as individual polymers and recycled again as raw materials.
FIG. 2 shows a case where the support is a drum, and the method of applying the solution to the support is such that the solution is allowed to flow from the slit of the extrusion die 14 onto the drum and then dried.
FIG. 3 shows a case where the solution is pumped up by a belt-like rotating support.

The entire apparatus of the present invention is preferably housed in a building, and methylene chloride leaked into the air should be sent to an adsorption tank together with air to be adsorbed and regenerated. The inner wall of this building should be such that the metal surface is not exposed. This is to prevent corrosion by hydrogen chloride and hydrochloric acid.
In this case, the polyolefin film such as polyethylene and polypropylene having high solvent resistance and high methylene chloride resistance, and materials such as polyethylene terephthalate and polyethylene 2,6 naphthalate having high methylene chloride resistance and excellent heat resistance are described above. It is even better to use a coated metal surface.

  Since the operation of the apparatus of the present invention is hardly performed at a high temperature (for example, 100 ° C. or higher), the outer periphery of the apparatus can be made of a polymer resin material or the like. In this way, for example, if a transparent resin is used, there is an advantage that the internal operating state of the apparatus of the present invention can be known from the outside, and it is easy to cope with an abnormality. The entire device should be housed in a building surrounded by plastic material, except for heavy structures from floor to ceiling. Further, it is preferable to cover the building several times with a plastic material because methylene chloride can be prevented from leaking into the outside air. More preferably, equipment is provided at a suitable location beside each enclosure so that the air concentration of methylene chloride can be monitored at all times. As the metal material, a corrosion-resistant material such as SUS-316L is usually used. However, in particular, the equipment in a portion that comes into contact with a gas containing methylene chloride at a high temperature uses a metal material that is more resistant to corrosion, such as Hastelloy. preferable.

  Thus, according to the present invention, the recovery method of the present invention is provided by using, for example, the recovery apparatus as described above. That is, a method for recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved, wherein (1) the solution is brought into contact with the support to form a liquid film on the support; (2) The liquid film is heated, (3) and then the liquid film is peeled off from the support. (4) The peeled liquid film is transported and taken out as a film. (5) On the other hand, the solvent evaporated by the heating is captured by cooling. This is a method for recovering the solvent. Such a recovery method of the present invention is fully understood from the above description.

  Further, by the above apparatus, the separation method of the present invention, that is, a method of separating a polymer and a solvent from a solution comprising a polymer and a solvent in which the polymer is dissolved, comprising: (1) contacting the solution with a support and A method for separating a polymer and a solvent is provided, in which a liquid film is formed on a support, (2) the liquid film is heated, and (3) the solvent evaporated by the heating is cooled and condensed. Such a separation method of the present invention is fully understood from the above description.

[Example 1]
As shown in FIG. 1, 20% by weight of a methylene chloride solution of polycarbonate was introduced into the solution tank 2 from an external solution reservoir tank 100. The temperature of the tank 100 and the solution tank 2 was maintained at 15 to 18 ° C. The flow rate from the tank 100 was automatically adjusted and maintained so that the liquid level in the tank was constant. In this way, the solution was pumped as a liquid film on the roll so that the liquid level 5 of the solution slightly touched the lower surface of the pump (drum) 6. The speed of the roll was adjusted so that the thickness of the liquid film was about 250 μm. At this time, the pumping roll was heated with warm air so as to reach 55 ° C. from the inner surface of the roll. By this heating, the liquid film is rapidly dried. When the amount of methylene chloride in the liquid film reached about 20%, the semi-dry film was peeled off from the cooling roll, pulled up through the take-up roll 7, and taken out of the apparatus through the next transport roll. The film was further dried by blowing hot air of 55 ° C. from both sides in the space between the take-up roll 7 and the transport roll 8. The methylene chloride released from the liquid film and cooled in the tank was cooled by the cooling plate (condensing part) 10 shown in the figure, condensed, flowed down through the installed flow path and collected in the basket 13. Further, the methylene chloride condensed on the outer peripheral wall surface is collected in the basket 13 along the wall and sent to the next process through the solvent conduit 11. The film that came out of the collecting device through the transport rolls 8 and 9 had a thickness of about 50 μm. The film thus obtained had a remaining amount of methylene chloride of 5% by weight. This was further subjected to a pulverizer to obtain a flake pulverized product. This was dissolved again in methylene chloride and formed into a solution to form an optical film. The characteristics of this film are the same as a new polycarbonate film formed without collecting molecular weight, hue, foreign matter, etc., and it was confirmed that there was no substantial deterioration (change) of the polycarbonate resin by this recovery operation. It was.

  The methylene chloride separated from the solution was stored in the storage tank 101 which is the next step. The methylene chloride vapor in the separation tank was sent together with air to a methylene chloride adsorption tank (activated carbon layer) 103 using activated carbon as a medium to separate methylene chloride and air. The adsorbed methylene chloride was desorbed with water vapor and stored in the storage tanks 101 to 102 in the next step. Thereafter, the water-containing methylene chloride was passed through a dehydrating apparatus 104 using a molecular sieve as a dehydrating agent to remove moisture, and was reused in the same manner as new methylene chloride. The purity of this methylene chloride was analyzed for volatile components, non-volatile components, acid components, etc., and it was confirmed that there was substantially no change from new methylene chloride.

  The recovery device, recovery method, and separation method of the present invention can separate and recover the polymer and the solvent, so that each can be reused as a raw material, and is environmentally friendly.

It is one conceptual diagram of the apparatus of this invention. It is one conceptual diagram of the apparatus of this invention. It is one conceptual diagram of the apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recovery apparatus 2 Solution tank 3 Partition 4 Hot air blowing nozzle 5 Solution surface 6 Drum 7 Take-off roll ((solution) liquid film peeling part)
8 Transport roll (nip roll)
9 Transport roll (nip roll)
10 Cooling plate (condensing part)
11 Solvent conduit 12 Cooling plate 13 樋 14 Extrusion die 100 Solution reservoir tank 101 Storage tank 102 Static tank 103 Adsorption tank (activated carbon layer)
104 Dehydrator

Claims (13)

An apparatus for recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved,
An apparatus for recovering a solvent, comprising: a solution storage section, a liquid film forming section, a liquid film drying section, a liquid film peeling section, a liquid film transport section, and a solvent recovery section.   The recovery apparatus according to claim 1, wherein the liquid film forming unit includes a rotating body for contacting the solution.   The recovery device according to claim 1, wherein the solvent recovery unit includes a condensing unit that captures the solvent as a liquid.   The collection | recovery apparatus in any one of Claims 1-3 which exists in substantial sealed space.   The recovery device according to any one of claims 1 to 4, wherein the polymer is an aromatic polycarbonate and the solvent is methylene chloride. A method of recovering a solvent from a solution containing a polymer and a solvent in which the polymer is dissolved,
(1) A solution is brought into contact with a support to form a liquid film on the support,
(2) heating the liquid film;
(3) Next, the liquid film is peeled off from the support,
(4) The peeled liquid film is conveyed and taken out as a film,
(5) On the other hand, the solvent evaporated by the heating is captured by cooling and recovered.
A method for recovering a solvent.   The collection method according to claim 6, wherein the support is a rotating body.   The recovery method according to claim 6 or 7, which is carried out in a substantially enclosed space.   The recovery method according to any one of claims 6 to 8, wherein the polymer is an aromatic polycarbonate and the solvent is methylene chloride. A method of separating a polymer and a solvent from a solution comprising a polymer and a solvent in which the polymer is dissolved,
(1) A solution is brought into contact with a support to form a liquid film on the support,
(2) heating the liquid film;
(3) Next, the solvent evaporated by the heating is cooled and condensed.
A method for separating a polymer and a solvent.   The separation method according to claim 10, wherein the support is a rotating body.   The separation method according to claim 10 or 11, wherein the separation method is performed in a substantially enclosed space.   The separation method according to any one of claims 10 to 12, wherein the polymer is an aromatic polycarbonate and the solvent is methylene chloride.

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