JP4125879B2 - Solvent regeneration apparatus and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solvent regeneration apparatus and method for distilling and regenerating a contaminated hydrocarbon solvent used for cleaning or the like.
[0002]
[Prior art]
Conventionally, as a technology for distilling and reusing a contaminated solvent such as a hydrocarbon solvent used for cleaning, a vacuum distillation regenerator disclosed in Japanese Patent Application Laid-Open No. 2000-345375, A vacuum distillation regenerator disclosed in Kaihei 7-136402 is known.
[0003]
A conventional vacuum distillation regenerator will be described with reference to FIG. FIG. 2 is a schematic diagram showing an example of the configuration of a conventional vacuum distillation regenerator.
[0004]
As shown in FIG. 2, an evaporating heat exchanger 100 that evaporates the contaminated solvent, and a condensing heat exchanger that cools the solvent vapor evaporated by the evaporating heat exchanger 100 to form a liquid phase solvent again. 102. A heating coil 104 in which steam or heat transfer oil circulates is provided in the evaporation heat exchanger 100. A cooling coil 106 through which cooling water circulates is provided in the condensing heat exchanger 102. The upper outlet of the evaporation heat exchanger 100 and the upper inlet of the condensing heat exchanger 102 are connected by an inverted U-shaped pipe 108.
[0005]
A pollutant introduction pipe 110 is connected to the lower inlet of the evaporation heat exchanger 100. The contaminated solvent introduction pipe 110 is provided with a solvent supply valve 112, a flow meter 114, a flow rate adjustment valve 116, a filter 118, and a filter maintenance valve 120.
[0006]
A pipe 122 is branched from between the connecting portion of the contaminated solvent introduction pipe 110 to the evaporation heat exchanger 100 and the solvent supply valve 112. The piping 122 is provided with a valve 124 and connected to a contamination recovery tank 126 for recovering the contaminated liquid accumulated in the evaporation heat exchanger 100. Further, the contamination recovery tank 126 is connected to the inverted U-shaped pipe 108 via the pipe 128. The pipe 128 is provided with a valve 130.
[0007]
A depressurization mechanism 132 that depressurizes the condensing heat exchanger 102 and the evaporating heat exchanger 100 is connected to the bottom outlet of the condensing heat exchanger 102. The decompression mechanism 132 includes an ejector 136 connected to the bottom outlet of the condensation heat exchanger 102 via a check valve 134, a solvent tank 138, and a solvent pump 140. A solvent circulation system is constructed in which the solvent is sucked into the solvent pump 140 from the solvent tank 138 and returned to the solvent tank 138 again through the ejector 136. Thus, the pressure reducing mechanism 132 by the ejector effect is constructed.
[0008]
Next, the regeneration of the solvent by the conventional vacuum distillation regeneration apparatus will be described.
[0009]
In advance, the evaporation heat exchanger 100 and the condensation heat exchanger 102 are depressurized to a predetermined pressure by the depressurization mechanism 132. Then, a predetermined amount of contaminated solvent is introduced into the evaporation heat exchanger 100 from the contaminated solvent introduction pipe 110, and the solvent supply valve 112 is closed.
[0010]
Next, steam or heat transfer oil is circulated in the heating coil 104 in the evaporation heat exchanger 100 to heat the solvent in the evaporation heat exchanger 100. The solvent vapor generated by this heating is introduced into the condensation heat exchanger 102 through the inverted U-shaped pipe 108.
[0011]
The solvent vapor introduced into the condensing heat exchanger 102 is cooled and liquefied by the cooling coil in which the cooling water of the condensing heat exchanger 102 circulates. By cooling in this way, the solvent vapor is again collected in the solvent tank 138 of the decompression mechanism 132 as a liquid phase solvent.
[0012]
In this way, the contaminated solvent is heated and evaporated to concentrate the solvent contaminants in the evaporation heat exchanger 100. The contaminated liquid containing the contaminants concentrated in the evaporation heat exchanger 100 is periodically collected in the pollution collection tank 126 via the pipe 122. When collecting the contaminated liquid, the valve 130 of the pipe 128 is opened to make the pressure in the evaporation heat exchanger 100 and the pollution collection tank 126 the same, and then the valve 124 of the pipe 122 is opened.
[0013]
[Problems to be solved by the invention]
As described above, the conventional vacuum distillation regenerator generates solvent vapor in the evaporation heat exchanger 100 and concentrates contaminants of the contaminated solvent in the evaporation heat exchanger 100. Therefore, depending on the type of contaminant contained in the contaminated solvent, it is fixed inside the evaporation heat exchanger 100. For this reason, cleaning of the evaporating heat exchanger 100 may be frequently required, and further, there may be a situation where the safe operation of the evaporating heat exchanger 100 is hindered.
[0014]
For example, a solvent used for cleaning a paint containing a thermosetting component such as unsaturated polyester contains fine particles of the thermosetting component as well as a pigment as a contaminant. When the solvent is vaporized in the evaporation heat exchanger 100, the particles of the thermosetting component adhere to the inner surface of the evaporation heat exchanger 100. For this reason, the efficiency of the evaporating heat exchanger 100 is lowered, and further, the evaporating heat exchanger 100 may be clogged with contaminants and become in a closed state where the operation becomes impossible.
[0015]
The object of the present invention is to efficiently distill and recycle even a solvent containing contaminants that change due to heat, such as thermosetting, and highly viscous contaminants, without reducing the efficiency or blocking of the heat exchanger. It is an object of the present invention to provide a solvent recycling apparatus and method.
[0016]
[Means for Solving the Problems]
The above-mentioned purpose is a distillation can for storing a solvent and a lower side than the distillation can. And the evaporation of the solvent is suppressed by the hydraulic pressure. A heat exchanger that is disposed at a position and heats the solvent supplied from the distillation can and reintroduces it into the distillation can in a liquid state, and cools the vapor of the solvent generated in the distillation can. And a condenser for obtaining a regenerated solvent in a liquid phase state.
[0017]
The solvent regeneration apparatus may further include a decompression unit that decompresses the inside of the distillation can.
[0018]
The solvent regenerator further includes a recovery means for recovering the regenerated solvent obtained in the condenser, and the recovery means includes an upper vessel connected to an outlet of the regenerated solvent of the condenser. , At the bottom of the upper vessel, For opening and closing You may make it have a lower stage vessel connected via piping which has a valve.
[0019]
The solvent regenerator further includes a recovery means for recovering the regenerated solvent obtained in the condenser, and the recovery means includes an upper vessel connected to an outlet of the regenerated solvent of the condenser. , At the bottom of the upper vessel, For opening and closing A lower vessel connected through a pipe having a valve, and the pressure reducing means may also reduce the pressure in the upper vessel and / or the lower vessel.
[0020]
In addition, the purpose is to put the solvent in a distillation can, and to lower the solvent in the distillation can below the distillation can. And a heat exchanger arranged at a position to suppress evaporation of the solvent by liquid pressure And heated, and the heated solvent From the heat exchanger In liquid phase Above Re-introducing into a distillation can, generating a vapor of the solvent in the distillation can, and cooling the vapor of the solvent generated in the distillation can to obtain a regenerated solvent in a liquid phase state from which contaminants have been removed It is achieved by a solvent regeneration method characterized by the following.
[0021]
Further, in the above solvent regeneration method, in order to recover the regeneration solvent obtained by cooling the solvent vapor generated in the distillation can, an upper vessel and a lower portion of the upper vessel are provided. For opening and closing A lower vessel connected via a pipe having a valve, and when the regenerated solvent in the lower vessel is less than a predetermined amount of liquid, the valve is opened and the lower vessel is passed through the upper vessel. When the regenerated solvent in the lower vessel exceeds a predetermined amount of liquid, the valve is closed to separate the upper vessel and the lower vessel into the upper vessel. The regenerated solvent may be recovered and the regenerated solvent in the lower vessel may be discharged.
[0022]
In the solvent regeneration method, the solvent vapor may be generated in the distillation can in a state where the inside of the distillation can is decompressed.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
A solvent recycling apparatus and method according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a diagram showing the configuration of the solvent regeneration apparatus according to the present embodiment.
[0024]
[1] Solvent regenerator
First, the solvent regeneration apparatus according to the present embodiment will be described with reference to FIG.
[0025]
The solvent regeneration apparatus according to the present embodiment is provided with a distillation can 10 in which a solvent is distilled, and is filled with a contaminated solvent to be regenerated. A condenser 12 that condenses the solvent vapor generated in the distillation can 10 is connected to the tower portion of the distillation can 10 via a pipe 14. The distillation can 10 is connected to a feed pipe 11 for supplying a contaminated solvent.
[0026]
A heat exchanger 16 for heating the solvent supplied from the distillation can 10 is provided at a position below the distillation can 10. The distillation can 10 and the heat exchanger 16 include a pipe 20 for supplying the solvent from the distillation can 10 to the heat exchanger 16 and a pipe 18 for returning the solvent heated by the heat exchanger 16 to the distillation can 10 again. And connected by. The connection position of the pipes 18 and 20 to the distillation can 10 is a position where the solvent of the distillation can 10 is filled. The piping 20 is provided with a circulation pump 22 for sending the solvent heated by the heat exchanger 16 to the distillation can 10.
[0027]
A recovery unit 24 that recovers the solvent condensed by the condenser 12 is connected to the condenser 12. The recovery unit 24 has an upper vessel 26 and a lower vessel 28 for taking out the solvent from the condenser 12. The upper vessel 26 is connected to the solvent outlet of the condenser 12 via a pipe 30. The lower vessel 26 is connected to a position below the upper vessel 26 via a pipe 32. The pipe 32 is provided with a valve 34. The pipe 32 is connected to the bottom of the upper vessel 26, but may be the lower part.
[0028]
A vacuum pump 38 is connected to the upper vessel 26 via a pipe 36. A vacuum pump 38 is connected to the lower vessel 28 via a pipe 40 branched from the pipe 36. The pipes 36 and 40 are provided with valves 42 and 44, respectively.
[0029]
A pipe 46 for discharging the solvent recovered in the lower vessel 28 is connected to the bottom of the lower vessel 28. The piping 46 is provided with a valve 48. A pipe 50 for introducing compressed air into the lower vessel 28 is connected to the upper portion of the lower vessel 28. The pipe 50 is provided with a valve 52. Note that compressed nitrogen may be used instead of compressed air.
[0030]
A bottom of the distillation can 10 is connected via a pipe 56 to a contaminated liquid reservoir 54 for discharging a contaminated liquid in which the contaminants collected at the bottom of the distillation can 10 are concentrated. The pipe 56 is provided with a valve 58.
[0031]
A vacuum pump 38 is connected to the contaminated liquid reservoir 54 via a pipe 60 branched from the pipe 36. The pipe 60 is provided with a valve 62. A pipe 64 for introducing compressed air into the contaminated liquid reservoir 54 is connected to the contaminated liquid reservoir 54. A valve 66 is connected to the pipe 64. A piping 68 for discharging the contaminated liquid is provided at the bottom of the contaminated liquid reservoir 54. The pipe 68 is provided with a valve 70.
[0032]
As described above, the solvent regeneration apparatus according to the present embodiment is mainly characterized in that the heat exchanger 16 for heating the solvent stored in the distillation can 10 is located below the distillation can 10. By the liquid pressure in the pipes 18 and 20 by disposing the heat exchanger 16 below the distillation can 10, it is possible to suppress the evaporation of the solvent in the heat exchanger 16 and the pipes 18 and 20. . Further, since the solvent in the liquid phase is circulated between the distillation can 10 and the heat exchanger 16 by the circulation pump 22, the speed of the solvent passing through the heat exchanger 16 is high, and the temperature of the heat exchanger 16 is increased. Even if the difference is small, the amount of heat necessary to vaporize the solvent can be supplied. As described above, since the solvent is constantly circulated in a liquid phase state between the distillation can 10 and the heat exchanger 16, it is possible to prevent the contaminants from sticking in the heat exchanger 16.
[0033]
Below, each component of the solvent reproduction | regeneration apparatus by this embodiment is explained in full detail.
[0034]
(A) Distillation can 10
The distillation can 10 stores a contaminated solvent to be regenerated and vaporizes the solvent. Examples of the renewable solvent include hydrocarbon solvents such as xylene, cyclohexane, and Solvesso (trade name).
[0035]
The distillation can 10 is provided with a liquid amount monitoring mechanism (not shown) for monitoring the amount of the accumulated solvent. Thereby, a solvent reproduction | regeneration apparatus can be controlled according to the liquid quantity of the solvent in the distillation can 10 monitored.
[0036]
At the height of the connection between the pipe 20 for supplying the solvent to the heat exchanger 16 of the distillation can 10 and the pipe 18 where the solvent heated by the heat exchanger 16 is reintroduced, Always filled with liquid solvent during operation. The contaminated solvent can be supplied into the distillation can 10 through the feed pipe 11.
[0037]
The distillation can 10 itself is not heated, and the solvent is vaporized in the distillation can 10 by the heat given to the solvent by the heat exchanger 16 described below. Further, when the solvent is vaporized, the inside of the distillation can 10 is depressurized by a vacuum pump 38 described later. Thereby, the solvent can be vaporized at a lower temperature.
[0038]
(B) Heat exchanger 16, circulation pump 22
The heat exchanger 16 is disposed below the distillation can 10 and heats the solvent supplied from the distillation can 10 via the pipe 18 and filled therein. In the heat exchanger 16, for example, a heating coil (not shown) through which steam or heat transfer oil circulates is provided, and the solvent is heated by contacting the heating coil with the solvent.
[0039]
The circulation pump 22 circulates the liquid phase solvent introduced from the pipe 20 by returning it to the distillation can 10 again after being heated by the heat exchanger 16. The circulation rate of the solvent circulated between the distillation can 10 and the heat exchanger 16 can be adjusted by the valve 23 according to the state of the solvent in the distillation can 10 and the like.
[0040]
The solvent regeneration apparatus according to the present embodiment is mainly characterized in that the heat exchanger 16 is disposed at a position below the distillation can 10 by at least 2 m or more. Specifically, the upper end of the heat exchanger 16 filled with the liquid phase solvent is disposed at least 2 m or more below the gas-liquid interface of the solvent in the distillation can 10. By disposing the distillation can 10 and the heat exchanger 16 in this manner, the vaporization of the solvent is suppressed by the liquid pressure in the pipes 18 and 20. That is, the solvent circulating between the distillation can 10 and the heat exchanger 16 can always remain in a liquid phase. Therefore, contaminants in the solvent do not adhere within the heat exchanger 16, and labor spent for maintenance such as cleaning of the heat exchanger 16 is reduced. Further, the heat exchanger 16 does not fall into a closed state where the contaminants are clogged and the operation becomes impossible.
[0041]
By circulating the solvent by the circulation pump 22 while being heated by the heat exchanger 16, the temperature of the solvent in the distillation can 10 rises, and the vaporization of the solvent occurs in the distillation can 10. Moreover, since the inside of the distillation can 10 is pressure-reduced so that it may mention later, the vaporization of the solvent occurs at a lower temperature.
[0042]
(C) Condenser 12
The condenser 12 cools and liquefies the solvent vapor introduced from the distillation can 10 through the pipe 14. For example, a cooling coil (not shown) through which cooling water circulates is provided in the condenser 12, and the solvent vapor is cooled and liquefied by contacting the cooling coil with the solvent vapor.
[0043]
(D) Collection unit 24 (upper vessel 26, lower vessel 28)
The recovery unit 24 is for recovering the solvent cooled by the condenser 12 and liquefied, and has an upper vessel 26 and a lower vessel 28 in which the solvent is stored.
[0044]
The upper vessel 26 directly receives the liquid-phase solvent accumulated at the bottom of the condenser 12. The lower vessel 28 receives the solvent from the upper vessel 26 through the pipe 34. When the amount of solvent accumulated in the lower vessel 28 exceeds a predetermined amount, the solvent in the lower vessel 28 can be recovered from the pipe 46 connected to the bottom of the lower vessel 28.
[0045]
During distillation of the solvent, the inside of the upper vessel 26 and the lower vessel 28 is depressurized by the vacuum pump 38. When recovering the solvent from the lower vessel 28 via the pipe 46, first, the valve 34 of the pipe 32 is closed to separate the upper vessel 26 and the lower vessel 28. Next, the valve 44 of the pipe 40 is closed to stop the decompression of the lower vessel 28. Next, the inside of the lower vessel 28 is pressurized by opening the valve 52 of the pipe 50 and introducing compressed air into the lower vessel 28. Then, the valve 48 of the pipe 46 is opened to recover the solvent from the lower vessel 28. While the solvent is recovered from the lower vessel 28, the solvent cooled and liquefied by the condenser 12 can be stored in the upper vessel 26. The procedure for recovering the solvent from the lower vessel 28 will be described in detail in the description of the solvent regeneration method.
[0046]
(E) Vacuum pump 38
The vacuum pump 38 depressurizes the inside of the upper vessel 26, the lower vessel 28, the condenser 12, and the distillation can 10 as described above. By reducing the pressure inside the distillation can 10 with the vacuum pump 38, the solvent in the distillation can 10 can be vaporized at a lower temperature than when the solvent is vaporized under normal pressure. Thereby, in the solvent regeneration apparatus according to the present embodiment, the solvent heated by the heat exchanger 16 can be vaporized in the distillation can 10 without directly vaporizing the solvent in the heat exchanger 16.
[0047]
Further, the vacuum pump 38 depressurizes the inside of the contaminated liquid reservoir 54 so that the contaminated liquid can be discharged from the bottom of the decompressed distillation can 10 to the contaminated liquid reservoir 54.
[0048]
Note that the pressure reduction by the vacuum pump 38 is desirably adjusted as appropriate according to the type of solvent to be regenerated. For example, in the case of a hardly volatile solvent, the inside of the distillation can 10 needs to be depressurized to a lower pressure.
[0049]
In addition, a mist recovery tank 39 is connected to the vacuum pump 38, and the solvent vapor contained in the exhaust gas can be recovered.
[0050]
(F) Contaminated liquid reservoir 54
The contaminated liquid reservoir 54 is for collecting the contaminated liquid containing the contaminants concentrated at the bottom of the distillation can 10. By opening the valve 58 of the pipe 56, the contaminated liquid collected in the bottom of the distillation can 10 in the contaminated liquid reservoir 54 is collected in the contaminated liquid reservoir 54.
[0051]
[2] Solvent regeneration method
Next, the solvent regeneration method according to the present embodiment will be described with reference to FIG. In the solvent regeneration apparatus before starting the solvent regeneration, all the valves other than the valve 23 are closed.
[0052]
First, the contaminated solvent to be regenerated is placed in the distillation can 10. Next, the operation of the vacuum pump 38 is started, the valves 44 and 34 are opened, and the pressure in the lower vessel 28, the upper vessel 26, the condenser 12, and the distillation can 10 is reduced to a predetermined pressure. At this time, the degree of vacuum is controlled by opening and closing the valve 44.
[0053]
Further, the valve 62 of the pipe 60 is opened, and the inside of the contaminated liquid reservoir 54 is depressurized to a predetermined pressure. This is because the contaminated liquid reservoir 54 cannot be drained unless the pressure in the distillation can 10 is the same. That is, by reducing the pressure in the contamination reservoir 54, it is possible to prevent the backflow of the liquid in the pipe 56 when the valve 58 is opened.
[0054]
Next, the solvent in the distillation can 10 is introduced into the heat exchanger 16 through the pipe 20 and the circulation pump 22 and heated, and the heated solvent is returned into the distillation can 10 through the pipe 18. In this way, the solvent in the liquid phase is circulated between the distillation can 10 and the heat exchanger 16 while the solvent is heated by the heat exchanger 16. The heating temperature of the solvent by the heat exchanger 16 is appropriately adjusted according to the type of solvent, the pressure in the distillation can 10 and the like.
[0055]
As described above, by circulating the solvent in the liquid phase state between the distillation can 10 and the heat exchanger 16, the temperature of the solvent in the distillation can 10 rises and gradually evaporates. Here, since the inside of the distillation can 10 is depressurized, the solvent evaporates at a lower temperature than in the case of normal pressure. The solvent vapor thus generated in the distillation can 10 is introduced into the condenser 12 via the pipe 14. After the evaporation is stabilized, the contaminated solvent is introduced through the feed pipe 11.
[0056]
The solvent vapor introduced into the condenser 12 is cooled and liquefied in the condenser 12. The liquid-phase solvent obtained by cooling the condenser 12 flows into the upper vessel 26 of the recovery unit 24 through the pipe 30 and further accumulates in the lower vessel 28 through the pipe 32. In this way, the solvent from which contaminants have been removed by distillation regeneration is accumulated in the lower vessel 28. The condenser 12 is set in advance such that the cooling water is passed through an internal cooling coil to condense the vaporized solvent.
[0057]
On the other hand, the contaminants of the solvent are concentrated at the bottom of the distillation can 10. Therefore, the valve 58 of the pipe 56 is periodically opened, and the contaminated liquid containing the contaminants at the bottom of the distillation can 10 is discharged to the contaminated liquid reservoir 54.
[0058]
When the contaminated liquid in the contaminated liquid reservoir 54 exceeds a predetermined amount, the contaminated liquid is discharged from the contaminated liquid reservoir 54 according to the following procedure. First, the valve 62 of the pipe 60 is closed to stop the pressure reduction in the contaminated liquid reservoir 54. Next, the valve 66 of the pipe 64 is opened, and compressed air is introduced into the contaminated liquid reservoir 54 and pressurized. Next, the valve 70 of the pipe 68 provided at the bottom of the contaminated liquid reservoir 54 is opened to discharge the contaminated liquid out of the contaminated liquid reservoir 54.
[0059]
As described above, in this embodiment, since the contaminants of the solvent are concentrated in the distillation can 10, the contaminants are fixed in the heat exchanger 16 even if the solvent contains the contaminants of the thermosetting component. There is nothing to do.
[0060]
Here, a procedure for recovering the distilled and regenerated solvent from the lower vessel 28 will be described.
[0061]
First, the valve 42 of the pipe 36 that connects the upper vessel 26 and the vacuum pump 38 is opened. Next, the valve 34 of the pipe 32 that connects the upper vessel 26 and the lower vessel 28 is closed, and the upper vessel 26 and the lower vessel 28 are separated.
[0062]
Next, the valve 44 of the pipe 40 is closed, and the decompression of the lower vessel 28 by the vacuum pump 38 is stopped. Thus, while recovering the solvent from the lower vessel 28, the solvent distillation and regeneration are continued through the upper vessel 26 while reducing the pressure in the condenser 12 and the distillation can 10. Then, the solvent from the condenser 12 is stored in the upper vessel 26. Note that the pressure reduction in the upper vessel 26, the condenser 12 and the distillation can 10 during this time is adjusted by opening and closing the valve 42 of the pipe 36 connecting the vacuum pump 38 and the upper vessel 26.
[0063]
Next, the valve 52 of the pipe 50 is opened to pressurize the inside of the lower vessel 28. Then, the valve 48 is opened and the solvent is recovered from the pipe 46.
[0064]
Thus, in this embodiment, since the solvent recovered by distillation can be recovered intermittently, there is no need to interrupt the solvent distillation regeneration, and the solvent can be efficiently regenerated. Further, since the reduced pressure state in the distillation can 10 can be kept stable, the solvent can be distilled and regenerated with high purity.
[0065]
As described above, recovery of the regenerated solvent from the lower vessel 28 and discharge of the contaminated liquid containing contaminants at the bottom of the distillation can 10 are appropriately performed, and the solvent in the distillation can 10 is distilled and regenerated.
[0066]
Thus, according to this embodiment, by disposing the heat exchanger 16 for heating the solvent below the distillation can 10, the evaporation of the solvent in the heat exchanger 16 is suppressed, and the inside of the distillation can 10. As the solvent evaporates, the contaminants in the heat exchanger 10 do not adhere, the labor required for cleaning the heat exchanger 10 can be reduced, and the blockage of the heat exchanger 10 is prevented. can do.
[0067]
[Modified Embodiment]
The present invention is not limited to the above embodiment, and various modifications can be made.
[0068]
For example, the control of the solvent regenerating apparatus such as opening and closing of the valve in the above embodiment is automatically controlled according to the height of the liquid level in the distillation can 10, the height of the liquid level in the upper vessel 26 and the lower vessel 28, or the like. You may do it.
[0069]
In addition, as the heat exchanger 16 in the above embodiment, various types of heat exchangers such as a plate type and a spiral type can be applied. However, since the internal flow rate is constant, a shell-and-tube type heat exchanger is used. An exchanger is preferred.
[0070]
Further, the solvent to be regenerated is supplied into the distillation can 10 in the above embodiment according to the amount of the solvent in the distillation can 10 and the solvent is continuously distilled and regenerated. You may go to
[0071]
In the above embodiment, the vacuum pump 38 is used as means for reducing the pressure in the distillation can 10 or the like. However, instead of the vacuum pump 38, for example, a means for reducing the pressure in the distillation can 10 by using an ejector is configured. Also good.
[0072]
【The invention's effect】
As described above, according to the present invention, the solvent is put into the distillation can, and the solvent in the distillation can is placed below the distillation can. The heat exchanger is located at a position where the evaporation of the solvent is suppressed by the hydraulic pressure Heated to supply the heated solvent From heat exchanger Re-introduced into the still in the liquid phase state, generates solvent vapor in the still, and cools the solvent vapor generated in the still to obtain a regenerated solvent in the liquid state from which contaminants have been removed. Therefore, even a solvent containing contaminants that change due to heat, such as thermosetting properties, highly viscous contaminants, and the like, can be efficiently distilled and regenerated without causing a reduction in efficiency or blockage of the heat exchanger.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a solvent recycling apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic view showing an example of the configuration of a conventional vacuum distillation regenerator.
[Explanation of symbols]
10 ... Distillation can
11 ... Feed piping
12 ... Condenser
14 ... Piping
16 ... heat exchanger
18 ... Piping
20 ... Piping
22 ... circulation pump
23 ... Valve
24 ... Collection unit
26 ... Upper vessel
28 ... Lower vessel
30 ... Piping
32 ... Piping
34 ... Valve
36 ... Piping
38 ... Vacuum pump
39 ... Mist collection tank
40 ... Piping
42 ... Valve
44 ... Valve
46 ... Piping
48 ... Valve
50 ... Piping
52 ... Valve
54. Contaminated liquid reservoir
56 ... Piping
58 ... Valve
60 ... Piping
62 ... Valve
64 ... Piping
66 ... Valve
68 ... Piping
70 ... Valve
100 ... Heat exchanger for evaporation
102 ... Condensation heat exchanger 102
104 ... Heating coil
106: Cooling coil
108 ... Reverse U-shaped piping
110 ... Piping for supplying contaminated solvent
112 ... Supply valve
114 ... Flow meter
116 ... Flow rate adjusting valve
118 ... Filter
120 ... Filter maintenance valve
122 ... Piping
124 ... Valve
126 ... Pollution recovery tank
128 ... Piping
130 ... Valve
132 ... Depressurization mechanism
134. Check valve
136 ... Ejector
138 ... Solvent tank
140 ... solvent pump

Claims (7)

A distillation can for storing the solvent;
Heat that is disposed below the distillation can and at a position that suppresses evaporation of the solvent by liquid pressure, and heats the solvent supplied from the distillation can to reintroduce it into the distillation can in a liquid state. An exchange,
A condenser for cooling the vapor of the solvent generated in the distillation can to obtain a regenerated solvent in a liquid phase. The solvent regeneration apparatus according to claim 1, wherein
The solvent regenerator further comprising pressure reducing means for reducing the pressure in the distillation can. The solvent regeneration apparatus according to claim 1 or 2,
A recovery means for recovering the regenerated solvent obtained in the condenser;
The recovery means has an upper vessel connected to the outlet of the regenerated solvent of the condenser, and a lower vessel connected to a lower portion of the upper vessel via a pipe having a valve for opening and closing. A featured solvent recycling apparatus. The solvent regeneration apparatus according to claim 2, wherein
A recovery means for recovering the regenerated solvent obtained in the condenser;
The recovery means has an upper vessel connected to the outlet of the regeneration solvent of the condenser, and a lower vessel connected to a lower part of the upper vessel via a pipe having a valve for opening and closing ,
The said pressure reduction means also pressure-reduces the inside of the said upper vessel and / or the said lower vessel, The solvent reproduction | regeneration apparatus characterized by the above-mentioned. Put the solvent in the distillation can
Supply the solvent in the distillation can below the distillation can and heated to a heat exchanger arranged at a position to suppress evaporation of the solvent by liquid pressure ,
Heating above solvent and re-introduced into the distillation can remain in the liquid phase from the heat exchanger to generate steam of the solvent in the distillation pot,
A solvent regeneration method, wherein the solvent vapor generated in the distillation can is cooled to obtain a regenerated solvent in a liquid state from which contaminants are removed. The solvent regeneration method according to claim 5, wherein
In order to recover the regenerated solvent obtained by cooling the solvent vapor generated in the distillation can, the upper vessel is connected to a lower portion of the upper vessel via a pipe having a valve for opening and closing. A lower vessel and
When the regenerated solvent in the lower vessel is less than a predetermined amount of liquid, the valve is opened and the regenerated solvent is collected in the lower vessel through the upper vessel,
When the regenerated solvent in the lower vessel exceeds a predetermined amount of liquid, the valve is closed to separate the upper vessel and the lower vessel to collect the regenerated solvent in the upper vessel, and A method for regenerating a solvent, comprising discharging the regenerated solvent in a vessel. The solvent regeneration method according to claim 5 or 6,
The solvent regeneration method, wherein the vapor of the solvent is generated in the distillation can in a state where the inside of the distillation can is decompressed.

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