KR100665559B1 - Method and apparatus for reclaiming used solvent - Google Patents

Abstract

The present invention relates to a method for regenerating a used solvent containing a resin component consumed in a process of separating a resist resin component on a substrate or a used solvent used to dissolve a resist resin component in the manufacture of a semiconductor or liquid crystal display substrate. will be. This method includes removing the resin component, removing volatile impurities such as water, and purifying the solvent. First, the resin component removing step is performed. Next, after the purified solvent is evaporated, the regeneration solvent is recovered as the condensed solvent. An apparatus for performing this method is also described.

Description

Regeneration method and apparatus for used solvents {METHOD AND APPARATUS FOR RECLAIMING USED SOLVENT}

The present invention relates to a method and apparatus for regenerating a solvent. In particular, the present invention relates to a method and apparatus for regenerating a solvent used, such as a separation liquid used in a process of separating a substrate resist layer. The invention also relates to a method and apparatus for regenerating thinners and the like used to dissolve resins used in semiconductors, liquid crystal displays and other similar manufacturing techniques.

In the prior art, a heated solvent (separation liquid) is used to separate the substrate resist layer in the manufacture of a semiconductor or liquid crystal display. This separation solution usually consists of a mixture of monoethanolamine (hereinafter referred to as "MEA") and dimethyl sulfoxide (hereinafter referred to as "DMSO"). This mixture mixture is also water soluble and contains a small amount of water. The thinner also consists of a mixture of propylene glycol monoethylether acetate (hereinafter referred to as "PGMEA") and propylene glycol monoethylether (hereinafter referred to as "PGME"). The thinner mixture is water soluble and contains a small amount of water.

In recent years, the size of semiconductors and liquid crystal display substrates has increased. Thus, the amount of separation liquid and thinner used in the manufacture of semiconductors and liquid crystal displays was increased. After the separation liquor and thinner are used, the waste processor collects them for disposal. However, these collections are very expensive, and wastewater treatment adversely affects the global environment. Therefore, it is desirable to recycle the used solvent rather than to treat the used solvent, such as separation liquid or thinner after use.

The conventional method of regenerating a used solvent is distilling the used solvent and separating it into each component. However, in this method, it is difficult to separate the separating solution or thinner after use so as to have a crediting agent having a component equivalent to the use-only agent. In addition, it is difficult to stably operate the regeneration apparatus for a long time while maintaining the quality of the regeneration liquid. Therefore, a specific apparatus and method for regenerating solvents used in the field of semiconductor and liquid crystal display devices have not been developed yet, and have been long pursued. In addition, if the importance is placed on the processing performance, the solvent regeneration apparatus will be larger, but it is desirable to supply a solvent regeneration apparatus having a high regeneration performance and maintaining the regeneration solvent quality and having a small size.

Accordingly, an object of the present invention is to solve one or more problems of the conventional solvent regeneration method and apparatus. In the present invention, the present invention is to regenerate used solvents such as separation liquids and thinners used in the manufacture of semiconductors and liquid crystal display substrates. The recycled solvent may be reused in the manufacturing process and preferably does not require disposal of the used solvent.

Another object of the present invention is to provide a solvent regeneration apparatus capable of regenerating used solvents such as separation liquids and thinners used in the manufacture of semiconductors or liquid crystal display substrates. The solvent regeneration device is preferably stable for a long time and relatively small.

In the present invention, the method for regenerating the solvent used includes removing the resin component, removing volatile impurities, and purifying the solvent. It is preferable that the resin component is removed first. In addition, after the purified solvent is completely evaporated, the regeneration solvent is recovered as a condensation solvent.

There is also provided an apparatus for regenerating a used solvent containing a resin component. The solvent used contains the resin component dissolved in the solvent during the separation process of the resist resin. The solvent regeneration apparatus includes a resin component removal apparatus for removing a resin component, a volatile component removal apparatus for removing volatile impurities, and a refining apparatus for purifying a solvent. It is preferable that the resin component removal apparatus is provided upstream. In addition, after the purified solvent is evaporated downstream, the regeneration solvent is recovered as a condensation solvent.

According to the method of the present invention, since the solvent component to be regenerated after the resin component is removed is purified, the purification process is not influenced by the suspended or dissolved resin component. Therefore, high purification efficiency can be obtained, and a high purity regeneration solvent can be obtained. In addition, according to the apparatus of the present invention, the apparatus can be operated stably for a long time without reducing the regeneration efficiency.

In addition to the above object, the features and advantages of the present invention can be more easily understood through the following detailed description together with the accompanying drawings and claims.

The solvent used in the present invention is a waste liquid used for dissolving or separating the resist resin during the manufacture of the semiconductor egg liquid crystal display substrate. Generally, the solvent used consists essentially of the main solvent component, the resist resin and a small amount of water.

As shown in Fig. 1, the method of the present invention includes a first step of removing the resin component (resist resin). Next, volatile components such as water are removed. Finally, the solvent is evaporated and then purified. As a result, the regeneration solvent is recovered as a condensation solvent. According to this method, since the nonvolatile resin component is removed in advance, the following process is not affected by the suspended or dissolved resin component. Thus, the playback apparatus can be operated stably.

In this method of obtaining a regenerating solvent, the resin component is removed in advance, the volatile components are removed, and finally the solvent is purified and condensed by evaporation. According to this method, the solvent flow can be simplified (this method is consistent with claim 1).

As shown in Fig. 2, the exhaust system exhausts the gas containing the solvent evaporated in the solvent treatment process into the atmosphere. This gas is condensable in the exhaust gas condensation step, and this exhaust gas condensation step may be carried out before the exhaust gas treatment step. This condensate can be adopted as the solvent used (this method is in accordance with claim 2). This used solvent can be used as a regeneration solvent.

In addition, as shown in Fig. 3, according to another method, a used solvent such as a separation liquid consisting of one or more main components (e.g., MEA and DMSO as main components) used in the resin component separation process may be used as a resin component, water, and the like. It can be regenerated by removing impurities (this method is consistent with claim 3).

In addition, as shown in FIG. 4, other methods may be used to separate thinners consisting of one or more principal components (eg, PGMEA, PGME as the principal component) used in a separation process or other processes. In particular, the thinner used can be regenerated by removing resist resin, water, and other impurities (this method is consistent with claim 4).

In the resin component removal step, the resin component can be removed at a high density by falling film concentrating means (this method is consistent with claim 5).

MEA is an example of a solvent that absorbs gas (CO 2) in air to produce salt (carbonate). This gas is separated from the salt in the volatile removal step (this method is in accordance with claimed 6).

The heat exchange means are installed in the middle part of each of the transfer apparatuses or upstream from the middle part, so that the solvent separated in each step can enter the previous step or the next step or the tank at low temperature. Thus, the life of the conveying means can be extended (this method is consistent with claim 7).

As mentioned above, the solvent component may be converted into a salt by absorbing the gas. In addition, the gas can be dissolved in the solvent. As shown in Fig. 5, the used solvent absorbing the gas is further processed in the degassing process, and the dissolved gas is separated by an ultrasonic application method or the like. As a result, various adverse effects which may occur in the sequential steps can be reduced, and the purity of the regeneration solvent can be increased (this method is consistent with claim 8).

As shown in Fig. 6, the quality of the regeneration solvent obtained in the purification step is controlled to be continuously monitored and optimized so that the quality of the solvent can be kept constant (this method is consistent with claim 9).

By increasing the pressure reduction, the solvent component can be separated from the used solvent at low temperatures. Corrosion resistant materials are used to prevent corrosion of the device due to corrosion solvents. This structure does not require the use of specific metals such as Hastelloy, which is a trade name for a group of nickel chromium molybdenum alloys which have acid resistance at elevated temperatures and have high strength as corrosion resistant materials (this method is consistent with claim 10) ).

The concentration of the solvent component mixed with volatile components (water, etc.) separated by evaporation is controlled in the volatile component removal step. In this step, the volatile components can be evaporated at a temperature higher than the cooling temperature in the next condensation step. As a result, the steam is convertible to condensate in the condensation step (this method is consistent with claim 11).

By supplying nitrogen gas under pressure, the purified regeneration solvent is transferred to and from the tank. As a result, the quality of the regenerating solvent can be maintained (this method is consistent with claim 12).

The volatile components separated in the purification step can be returned to the resin component removal step by waste liquid treatment or by a return pump. Typically, the volatile components are returned to the resin component removal step to repeat the same process. As a result, the separation efficiency can be improved (this method is consistent with claim 13).

As shown in Fig. 7, the regeneration device includes a resin component removal device, a volatile component removal device, and a refining device, which are arranged sequentially from the upstream side to the downstream side. Since the resin component is removed in advance, adverse effects due to the resin component do not occur in the downstream apparatuses in the sequential steps. In addition, a high purity regeneration solvent is obtained because the regeneration solvent is finally obtained by evaporation and condensation (this method is the same as in claim 14).

The resin fraction removing apparatus includes the falling film type thickening apparatus shown in Fig. 8, so that the resin components are immediately separated (this method is the same as in claim 15).

By first removing the resin component (non-volatile component), adverse effects on the operation of the apparatus and the solvent quality are removed in advance. In addition, no deposit of impurities is produced in the distillation column in the next step including the volatile component removal step. Thus, a packed distillation column can be used (this method is the same as in claim 16).

A condensation means is provided to condense the volatile components removed by the evaporation method of the volatile matter removal device. The condensation means is kept warm to maintain the cooling temperature range. Thus, safe operation can be obtained (this method is the same as in claim 17).

In addition, by employing a packed distillation column, the size of the regeneration device can be easily reduced. Thus, in terms of ease of transport and structure, the whole apparatus can be manufactured in a plurality of units (this method is the same as in claim 18).

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, the solvent regeneration device (hereinafter referred to as "regeneration device 1") will be described. This regeneration device 1 can be used to perform the solvent regeneration method of the present invention. 7 to 12 show the structure of the playback apparatus 1.

Solvent (L) used for regeneration may be a waste liquid collected after fabricating a semiconductor or liquid crystal device. In addition, the solvent L used may be a condensate collected from the exhaust system.

As shown in FIG. 7, the solvent recovery tank for storing the used solvent removes the resin component corresponding to the resin component removal apparatus and the falling film type concentration means of the present invention via the first pipe 4 and the pump 3. It is connected to the top of the device 5. The inlet port 6a and the outlet port 6b for the heating steam are disposed on the bottom surface of the resin component removing apparatus 5. In addition, the resin component outlet port 6c is disposed at the bottom of the resin component removing apparatus 5 and connected to the resin component tank 7. The resin component may be discharged from the resin component tank 7.

In addition, the vapor discharge port 8a and the conveyance solvent import port 8b are disposed above the resin component removing apparatus 5. Typically, the steam discharge port 8a is connected to the middle portion of the distillation column 9 corresponding to the volatile component removal device of the present invention via the second pipe 8. The distillation column 9 is packed and the filling 10a is disposed inside the top of the distillation column 9. The recirculation port 11 is arranged above the filling 10a and the steam outlet 12 is arranged at the top of the distillation column 9.

The third pipe 13 connects the steam discharge port 12 to the recirculation tank 16 via the first capacitor 14 and the first vent capacitor 15. Both condensers 14 and 15 hold coolant circulating through the passages. The recirculation tank 16 has a recirculation passage 18, a conveying pipe 20 and a volatile component discharge passage 21. The solvent in the recirculation tank 16 can be removed from its bottom and is led by the recirculation pump 17 through the recirculation passage 18 to the recirculation port 11. A part of solvent is conveyed to the recirculation tank 16 via the return valve 20 branched from the recirculation path 18 in the three-way valve 19. In addition, the volatile components can be removed from the upper portion of the recycle tank 16 and are led to the volatile component tank 22 through the volatile component discharge passage 21. The volatile component may be discharged from the volatile component tank 22.

In addition, the filling 10b is disposed inside the lower part of the distillation column 9. A tank 23 is provided below the filling 10b in the bottom of the distillation column 9. The circulation pipe 25 connects the inner top tank 23 to the heating reboiler 24, and the fourth pipe 28 connects the tank 23 to the rectification tower 27 via the transfer pump 26. Connect.

The rectifying tower 27 is in the form of a tray, and a plurality of trays are disposed in the upper part of the rectifying tower 27. The recirculation port 11 is arranged above these trays, and the vapor discharge port 31 is arranged on top of the rectification tower 27. The fifth pipe 32 connects the steam discharge port 31 to the recirculation tank 35 via the second capacitor 33 and the second vent condenser 34. Both condensers 34 and 35 contain coolant circulating through the passages.

The recirculation tank 35 has a recirculation passage 37 and a regeneration component discharge passage 38. The solvent in the recirculation tank 35 is removed from the bottom of the tank 35 and is led by the recirculation pump 36 to the recirculation port 30 along the recirculation passage 37. In addition, the solvent may be removed from the upper portion of the recirculation tank 35 through the regeneration component discharge passage 38.

In addition, a tank 39 is provided below the tray inside the bottom of the rectification tower 27. The circulation pipe 41 connects the inner top tank 39 to the heating reboiler 40, and the conveying passage 44 connects the tank (via the heat exchanger (heat exchange means) 42 and the conveying pump 43). 39) is connected to the return solvent import port 8b of the resin component removing device 5.

The regeneration component discharge passage 38 is connected to the first treatment solvent tank 45 and the second treatment solvent tank 46. The sixth pipes 47a and 47b connect the bottoms of the tanks 45 and 46 to the concentration control tank 48, respectively. In addition, the seventh pipe 50 connects the concentration control tank 48 to the chemical supply tank 51 via the filter 49. Teflon filter material is disposed within filter 49. The regeneration solvent in the chemical supply tank 51 may be supplied to a semiconductor or liquid crystal manufacturing process.

The branch pipe 50a branches off from the seventh pipe 50 between the filter 49 and the chemical supply tank 51. The branch pipe 50a is connected to the spectrometer 52 and then recombined with the seventh pipe 50.

In addition, the low pressure pipes 54a and 54b are provided with a pressure reducing device 53, such as a vacuum pump, for the first vent condenser 15, the second vent condenser 34, the volatile component tank 22, and the treatment solvent tank 45, 46). Therefore, the internal pressures of the distillation column 9, the rectification column 27, and the resin component removal apparatus 5 can also be reduced or reduced.

As shown in FIG. 8, the resin component removal apparatus 5 includes the sealed cylindrical body 55 and the heating means 56 provided around this cylindrical body 55. As shown in FIG. Steam or other gases are introduced from outside into the heating means 56. The heating means 56 heats the cylindrical body 55, and the inner surface of the cylindrical body consists of an evaporation surface 57. The cylindrical rotating body 58 is disposed rotatably coaxially inside the cylindrical body 55. The rotating body 58 has a brush 59 extending radially from the circumferential surface of the rotating body 58. The cylindrical body 58 rotates with the brush 59 in contact with the inner surface of the cylindrical body 55.

In addition, a thermometer and a pressure gauge are respectively installed on the upper, middle and lower portions of both the distillation column 9 and the rectification column 27 to measure the temperature and pressure inside the distillation column 9 and the rectification column 27. Can be.

In this embodiment, the reboilers 24 and 40 are installed outside the distillation column 9 and the rectification tower 27, respectively. However, the reboilers 24 and 40 may be formed in one piece with the tanks 23 and 39 inside the towers 9 and 27 (for example, in the form of calanderia), which have almost the same thermal efficiency. Reduce space requirements

As shown in FIG. 7 and FIG. 9, the volatile powder tank 22 is equipped with the nitrogen gas pipe 60 and the opening-closing valve 61a for guiding nitrogen gas to the volatile tank 22. As shown in FIG. In addition, a switching valve is provided to each system such as an air opening system connected to the tank 22, a solvent supply system from the upstream side (volatile component discharge passage 21), a pressure reduction system, and a discharge system from the tank 22. 61b, 61c, 61d, and 61e are provided.

Similarly, as shown in FIG. 10, the first and second treatment solvent tanks 45 and 46 have an on / off valve 64a, for guiding nitrogen pipes 62 and 63 and nitrogen gas to the tanks 45 and 46, respectively. 65a). In addition, switching valves 64b, 64c, 64d, 64e and 65b, 65c, 65d, 65e are installed in respective systems connected to the tanks 45, 46. In particular, the valves 64b and 65b are installed in the atmospheric opening system; The valves 64c and 65c are installed in the solvent supply system (renewable component discharge passages 38a and 38b; the valves 64d and 65d are installed in the pressure reducing system; and the valves 64e and 65e are the tanks 45 and 46). Installed in the discharge system from

In addition, as shown in FIG. 11, the heat insulating material 67 surrounds the outer circumferential surface of the first capacitor 14 connected to the top of the distillation column 9, the first vent capacitor 15, and the cooling pipe (cooling water). The heating means 66 is wrapped with the insulating material 67 and wraps the pressure reducing pipe. Heaters or other devices that supply heated steam (eg steam) and heat may be effectively used as the heating means 66.

Hereinafter, the operation of the regeneration device 1 according to the process steps and the flow of the solvent used will be described.

In FIG. 7, when the pressure reducing device (vacuum pump) 53 is operated, the resin component removing device 5, the distillation column 9, and the rectification tower 27 are vacuumed by the vacuum transmitted from the pressure reducing pipes 54a and 54b. It is kept almost in vacuum.

In addition, the heating apparatus heats the resin component removing apparatus 5, the distillation column 9, and the rectification column 27 to a predetermined temperature.

Accordingly, the pump 3 is operated to supply the used solvent L from the solvent recovery tank 2 to the resin component removing device 5. When the used solvent (L) is introduced into the resin component removing device (5), the solvent (L) in which the cylindrical rotor (rotor) 58 and the brush 59 are used is shown on the evaporation surface 57 as shown in FIG. Contact. As a result, the solvent L is dissipated in the form of a thin film and separated into a volatile component L1 and a nonvolatile component (resin component) L2. The volatile component L1 is discharged from the vapor discharge port 8a and introduced into the distillation column 9.

As the resin component removing apparatus 5, a "thin film vaporizer" manufactured by Nippon Sharyo Seizo Kaisha, Ltd. having the same structure as the resin component removing apparatus 5 may be used.

The nonvolatile component L2 decreases along the inner wall of the resin component removing apparatus 5, is received at the bottom, and is stored in the resin component tank 7 (see FIGS. 7 and 8). The volatile component (L1) introduced into the distillation column (9) is distilled in the filling (10a, 10b) by gas-liquid contact between the recycle solvent (Lr1) moving downwards and the steam moving upwards due to the heating. As a result, the volatile component (L3) is evaporated. The evaporated volatile component (L3) is moved upwards and is discharged from the vapor discharge port (12). The vapor is then condensed in the first condenser 14 and the second vent condenser 15. Cooling water is circulated around both condensers 14 and 15. The condensation solvent (solvent liquid) is temporarily stored in the circulation tank 16. Next, while maintaining the distillation equilibrium, the condensation solvent is discharged by the recirculation pump 17 from the bottom of the tank 16 to the recirculation port 11 of the distillation column 9 as the recirculation solvent Lr1. The excess solvent Le from the recycle solvent Lr1 is returned to the recycle tank 16. All overflows from the high solution level in recycle tank 16 are directed to volatile tank 22 through volatile discharge passage 21 and stored in tank 22 for discharge.

In order to release the volatile component L3 in the volatile component tank 22, the on / off valves (switching valves) 61c and 61d are closed and the on / off valves (switching valves) 61b are opened to release the pressure in the tank 22. Return to atmospheric pressure. Then, the on-off valve 61b is closed and the on-off valves 61a and 61e are opened. Therefore, nitrogen gas is supplied to the volatile component tank 22 through the opening / closing valve 61a, and the volatile component L3 is discharged. As the discharge is completed, the on / off valves 61a and 61e are closed and the on / off valve 61b is opened so that the pressure in the volatile component tank 22 returns to atmospheric pressure. Therefore, the on-off valves 61c and 61d are opened so that the volatile component L3 can be stored in the volatile component tank 22.

In addition, in FIG. 7, each component L4 having a high boiling point is stored as a liquid in the tank 23 in the distillation column 9. The transfer pump 26 is operated to supply the high boiling point component L4 to the bottom of the rectification tower 27 through the fourth pipe. The high boiling point component L4 introduced into the rectification tower is stored in the tank 39 in the rectification tower 27. Some of the high boiling point component (L4) is evaporated by heating and moves upwards. By gas-solution contact between the recirculating solution Lr2 moving down and the steam moving up by heating, the evaporated component L4 is distilled through the tray 29. As a result, the rectified component L5 (final regeneration component) moves upward and is discharged from the vapor discharge port 31. The rectified component L5 is then condensed in the second capacitor 33 and the second vent condenser 34. Cooling water is circulated around the two condensers 33 and 34. While maintaining the equilibrium of the distillation, the condensed and rectified component (L5) is temporarily stored in the recirculation tank (35), and then recirculated port of the rectification tower (27) at the bottom of the tank (35) by the recirculation pump (36). At 30, it is discharged as a recycling solvent Lr2. Overflow exceeding a predetermined level of the recirculation tank 35 is led to one of the treatment solvent tanks 45 and 46 through the regeneration component discharge passage 38 and treated as a regeneration solvent component (rectified component) L5. It is stored in the solvent tank (45, 46). When one of the treatment tanks is full, the other treatment tanks are used alternately.

As shown in Fig. 10, when the first treatment solvent tank is full, the shut-off valves 64c and 64d are closed and the shut-off valves 65c and 65d of the second treatment solvent tank 46 are opened, so that the regeneration solvent component ( L5) may be stored in the second treatment solvent tank 46.

When the first processing solvent tank 45 or the second processing solvent tank 46 is full, nitrogen gas is pumped into the tank. As a result, they are alternately withdrawn from one or the other of the tanks 45 and 46 filled with the regeneration solvent, and are supplied to the concentration control tank 48 through the sixth conduit 47a or 47b.

As shown in FIG. 10, in order to discharge | generate the regeneration solvent component L5 from the 1st process solvent tank 45, the opening-closing valve 64b is opened and the pressure in the tank 45 returns to atmospheric pressure. Then, valve 64b is closed and on / off valves 64a and 64e are opened. Therefore, nitrogen gas is supplied to the tank 45 through the on-off valve 64a, and the regeneration solvent component L5 is discharged from the tank. As the discharge is completed, the on-off valves 64a and 64e are closed and the valve 64b is opened to return the pressure in the tank 45 to atmospheric pressure. Therefore, the on-off valves 64c and 64d can be opened so that the regeneration solvent component L5 can be stored in the tank 45. A similar operation will be performed to open and close the valve to release the regeneration solvent component L5 from the second treatment solvent tank 46.

The concentration of the regeneration solvent component L5 in the concentration control tank 48 is essentially controlled within a specific concentration range. In particular, a spectrometer 52 is installed downstream from the concentration control tank 48 to immediately analyze the concentration of the regeneration solvent component L5. Based on the results of the analysis, if the concentration of one component, such as MEA and DMSO, does not reach a certain concentration range, an additional amount of this component will be supplied. If the concentration of the component is in a certain concentration range, such adjustment is not necessary (see FIGS. 6 and 7).

The spectrometer 52 measures the concentration of the component of the regeneration solvent L6 flowing through the branch pipe 50a through infrared analysis of the absorbed wavelength. If the concentration of the regeneration solvent L6 is not within the specified range, the spectrometer 52 will stop the regeneration apparatus or adjust the concentration. Various types of spectrometers may be used as the spectrometer.

The filter 49 removes the agglomerated particles in the regenerative solvent L6 whose concentration is adjusted. The filtered solvent L6 is stored in the chemical supply tank 51 to supply to the manufacturing process.

According to this embodiment, the regeneration efficiency of the solvent used can be improved, a regeneration solvent of reliable quality can be obtained, the life of the regeneration apparatus can be extended, the amount of the waste solvent and the disposal cost of the waste solvent Can be reduced. In addition, the adverse effects on the global environment due to the solvents used can be reduced.

In addition, in the distillation column 9 and the rectification column 27, the solvent component can be separated at a low temperature from the used solvent composed of the mixed components by evaporation under vacuum (decompression). Therefore, since the solvent is separated at a specific temperature or below a certain temperature, it is possible to operate the regeneration apparatus stably for a long time without using a specific material and often without having to replace parts frequently.

For example, as shown in Table 1, in the mixture of MEA and DMSO, when the pressure of SUS304 is reduced by 12.7 kpa from the conventional pressure P0, the temperature of SUS304 is reduced by approximately 40 ° C from the conventional temperature T0. As a result, the corrosion rate can be greatly reduced. Thus, the life of the regeneration device can be extended without using a specific material. In addition, the manufacturing cost can be reduced, and the delay time can be shortened.

Corrosion rate of SUS304 and temperature for separation solvent (MEA 70%, DMSO 30%) Pressure (kpa) P0 P0-6.7 P0-12.7 Temperature (℃) T0 T0-15 T0-40 Corrosion rate × 10 ^-5 (mm per year) 20 15 7 to 0

In addition, according to an embodiment of the present invention, the solvent L used is recyclable and reusable. As shown in Table 2 below, about 90% of the solvent (L) used is renewable. Therefore, the amount of solvent to be purchased is greatly reduced to less than 10% of the total amount of new solvent to be supplied. On the other hand, if such a regeneration device is not used, the conventional process has to purchase 100% of the solvent. Therefore, the purchase cost is reduced, and the amount of the waste solvent and thus the disposal cost of the waste solvent is greatly reduced. In addition, the process of exhaust concentration greatly increases the amount of solvent used that is renewable. Thus, the absolute amount of regenerated solvent can be increased, the exhaust gas treatment process is environmentally friendly, and the amount of new solvent to be purchased can be reduced. In addition, the quality of the regeneration solvent can be kept stable, and the life of the regeneration device can be extended.

Comparison of efficiency with and without solvent regeneration device (100 new solvents to be supplied) Solvent after use (L) Recycled Solvent Waste solvent Other (including exhaust system) New Solvents (Purchased Solvents) Not using the playback device 102 0 102 7 100 (100) Use of playback device 102 92 10 7 100 (8) Exhaust enrichment 107 96 11 2 100 (4)

The regeneration device 1 is formed by assembling the resin component removal device 5, the distillation column 9, the rectification tower 27, and the other parts in order. However, the regeneration device 1 is divided into device parts, and the plurality of regeneration devices are divided in advance. To form a unit. Each unit is interconnected at the installation site to form the playback device 1. Each unit can be interconnected at an installation site forming the playback device 1. For example, as shown in FIG. 12, the units 68, 69 are made separately in advance and interconnected at the installation site by bolts or other locking devices. By providing a connectable flange structure, connecting pipes or connecting devices between the units 68 and 69 can be installed immediately.

According to the first invention described in claim 1, the solvent component can be recovered and regenerated from the solvent used, and thus a usable solvent can be obtained.

According to the second invention of claim 2, the concentrate from the exhaust system can be recovered as a solvent component.

According to the third invention of claim 3, the separation liquid consisting of one or more main components can be recovered and regenerated.

According to the fourth invention of claim 4, thinners composed of one or more main components can be recovered and regenerated.

According to the fifth invention of claim 5, the resin component contained in the solvent used can be efficiently removed in advance, and therefore the following component separation treatment is easily performed.

According to the sixth invention of claim 6, the gas component can be separated in the volatile component removal step.

According to the seventh invention of claim 7, the life of the pump affected by the temperature can be extended.

According to the eighth invention of claim 8, since the excess gas dissolved in the solvent used can be removed in advance, recovery and regeneration efficiency can be improved.

According to the ninth invention as set forth in claim 9, the components of the regeneration solvent can be analyzed continuously during the operation of the regeneration apparatus, and immediate measures for correcting the abnormal condition can be performed. Therefore, a stable quality regeneration solvent can be supplied constantly to the chemical supply tank.

According to the 10th invention of Claim 10, the separation temperature of a solvent can be reduced by pressure reduction. By separating the solvent below a certain temperature, the regeneration apparatus can be operated stably for a long period of time without using a specific material and often without replacing parts.

According to the eleventh invention according to claim 11, the volatile components can be liquefied by condensing means under optimum conditions considering the given cooling temperature.

According to the twelfth invention of claim 12, the solvent can be stably supplied without impurities mixed in the solvent.

According to the thirteenth invention of claim 13, the high boiling point component in the purification step can be separated and reextracted, thus improving the regeneration efficiency.

According to the fourteenth invention of claim 14, it is possible to obtain a usable solvent as the solvent component is recovered and regenerated from the used solvent.

According to the fifteenth invention of Claim 15, the resin component contained in the solvent used is efficiently removed beforehand.

According to the sixteenth invention of claim 16, the distillation column and the entire apparatus thereof can be miniaturized, so that the cost can be reduced and the ease of construction can be improved.

According to the seventeenth invention of Claim 17, the production of precipitates caused by the change of the ambient temperature with the seasons is suppressed. In particular, excessive cooling due to low ambient temperatures during winter increases the formation of precipitates. On the other hand, according to the present invention, such a problem can be solved and a regenerating solvent of stable quality can be obtained.

According to the eighteenth invention of claim 18, the entire apparatus can be separated into functions by a plurality of units, so that the portability and ease of construction can be improved.

1 is a block diagram showing a processing process according to an embodiment of the present invention;

2 is a block diagram showing a processing step of the front end of the embodiment;

3 is a block diagram showing a processing step of the embodiment;

4 is a block diagram showing a processing step of the embodiment;

5 is a block diagram illustrating a processing process in accordance with a modification of the present invention;

6 is a block diagram showing a processing process according to another modification of the present invention;

7 is a schematic view showing the solvent regeneration device of the embodiment;

8 is a structural diagram showing the resin component removal apparatus of the solvent regeneration device taken apart;

9 is a schematic view showing a volatile component tank and a periphery of the device thereof;

10 is a schematic view showing two treated solvent tanks and their periphery;

11 is a schematic view showing the condensation means and the periphery of the device; And

12 is a schematic view showing a solvent regeneration device according to another embodiment of the present invention;

Claims (18)

Resin component removal step of removing the resin component from the solvent containing the resin component, A volatile component removing step of removing volatile impurities, and And a refining step of purifying the solvent, wherein the resin component removing step is performed first, and after the solvent is completely evaporated, the regenerating solvent is recovered as a condensed solvent. The method of claim 1, further comprising condensing the exhaust gas in an exhaust system for discharging vapor containing the evaporated solvent, wherein the condensate obtained in the condensation step is recovered as part of the used solvent. Regeneration method of the used solvent. The method of claim 1 or 2, wherein the solvent used comprises a separation solution consisting of at least one solvent. 3. The method of claim 1 or 2, wherein the used solvent comprises a thinner comprised of one or more solvents. 3. The method of claim 1 or 2, wherein the step of removing the resin component comprises a bottom film type concentration step. 3. The method of claim 1 or 2, wherein the volatile components and the gas components in the volatile component removal step are separated at or above a critical temperature at which the gas components can be separated. The method according to claim 1 or 2, wherein a heat exchanger is provided upstream from each conveying means used for recycling, conveying, or conveying the inter-process treatment liquid. The method for regenerating a used solvent according to claim 1 or 2, further comprising a gas removing step performed before the resin component removing step. According to claim 1 or claim 2, wherein the regeneration solvent obtained in the purification step is guided to the main supply pipe, a portion of the regeneration solvent is introduced into the conveying passage and returned to the main supply pipe via the spectroscopic analysis means, And said analyzing means continuously monitors the components of the treating solvent and controls the operation of the apparatus. The method of claim 1 or 2, wherein the separation temperature for separating the solvent component from the solvent used by evaporation is reduced by depressurization, and the separation temperature is lower than the critical temperature at which the material used to withstand corrosion. Regeneration method of used solvent. The method of claim 1 or 2, wherein as the concentration of the solvent in the volatile components is adjusted in the volatile component removal step, the outlet temperature in the volatile component removal step is controlled within the condensation temperature range, the cooling in the condensation step A method for regenerating used solvents, characterized in that it is controlled higher than temperature. The method according to claim 1 or 2, wherein the solvent is supplied from the tank and / or the treatment solvent tank to the next step by supplying nitrogen gas under pressure. 3. The conveying passage according to claim 1 or 2, wherein the conveying passage is provided in a waste liquid passage in which the residual liquid from the refining step is discharged as waste liquid, and the conveying passage is selectively used to return the residue to the resin component removing step. A method for regenerating a used solvent, which can be used. Resin component removal device for removing resin components, A volatile component removing device for removing volatile impurities, and And a refining apparatus for purifying the solvent, wherein the resin component removing apparatus is installed upstream, and after the purified solvent is evaporated downstream, the regeneration solvent is recovered as a condensation solvent. Solvent regeneration device. 15. The apparatus for regenerating used solvent containing a resin component according to claim 14, wherein said resin component removing device includes a bottom film type thickening device. 16. The regeneration apparatus for a solvent containing a resin component according to claim 14 or 15, wherein one or both of the volatile component removing device and the refining device include a packed distillation column. 16. The resin component according to claim 14 or 15, wherein a condensing means is provided for condensing the volatile components removed by the volatile component removing device, and the condensing means is kept warm so as to maintain a predetermined temperature range of the circulating coolant. Regeneration apparatus of a solvent containing. 16. The solvent regeneration device of claim 14 or 15, wherein the solvent regeneration device is mainly composed of a resin component removal device, a volatile component removal device, and a refining device. And the units are assembled together to form the solvent regeneration device.