JP2013111543A - Solvent recovery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solvent recovery system to reduce the cost required to recover solvent vapor in gas repeatedly supplied to a dryer.SOLUTION: The solvent recovery system 1 to supply exhaust in a drying chamber subjected to recovery treatment of the solvent vapor vaporized in the drying chamber to the drying chamber in the dryer for drying a material to be coated that is coated with a solvent includes: a condensation recovery unit 2 for carrying out condensation recovery of the solvent vapor contained in the exhaust by cooling the exhaust; an adsorption recovery unit 3 for carrying out adsorption recovery of the solvent vapor remaining in the exhaust passing through the condensation recovery unit; and a thermal utilization unit 12 for using at least a part of heat contained in the exhaust from the dryer for thermal regeneration of an adsorption material in the adsorption recovery unit for carrying out adsorption recovery of the solvent vapor.

Description

  The present invention relates to a solvent recovery system.

  In production facilities involving chemical treatment, solvent vapor is included in the exhausted gas. As a technique for recovering such solvent vapor, for example, a technique in which the solvent vapor is condensed and adsorbed on an adsorbent has been proposed (see Patent Document 1).

JP 2010-69435 A JP 2006-326504 A JP 2008-180459 A Japanese Patent No. 4642189

  For example, when a treatment for drying an object to be coated with various solvents, such as an electrode for a lithium ion battery to which an NMP solvent is applied, is effective in drying the applied solvent and the cost required for the drying process. In order to achieve a balance with the reduction, solvent vapor is recovered from the exhaust of a dryer (drying furnace) for drying an object to be dried to be dried and supplied to the dryer again. At this time, the dry air supplied to the dryer is required to have a relatively high dryness so that the applied solvent is surely dried, although it depends on the specifications required for the product to be processed.

  However, if the dryer is large, the cost required to maintain the dryness of the gas supplied to the dryer again is great. This invention is made | formed in view of such a problem, and makes it a subject to provide the solvent collection | recovery system which suppresses the cost required in collection | recovery of the gaseous solvent vapor | steam supplied again to a dryer.

  In order to solve the above problems, the present invention uses at least part of the heat contained in the exhaust of the dryer as a heat source for heating and regenerating the adsorbent that adsorbs and recovers the solvent vapor.

  Specifically, the solvent recovery system supplies air to the drying chamber of a dryer that dries an object to which the solvent is applied, and recovers the vapor of the solvent vaporized in the drying chamber. A condensation recovery part for condensing and recovering the solvent vapor contained in the exhaust, an adsorption recovery part for adsorbing and recovering the solvent vapor remaining in the exhaust that has passed through the condensation recovery part, and an exhaust of the dryer A heat utilization unit that utilizes at least a part of the contained heat for heating and regeneration of the adsorbent of the adsorption recovery unit that adsorbs and recovers the solvent vapor.

The solvent recovery system cools the exhaust of the dryer, condenses and recovers the solvent vapor contained in the exhaust, and further absorbs and recovers the solvent vapor remaining in the exhaust with an adsorbent. That is, when the solvent vapor is condensed and recovered, heat contained in the exhaust gas is removed with a heat medium. The temperature of the heating medium after cooling the exhaust of the dryer must be at least higher than the temperature of the exhaust of the dryer that passes through the adsorption recovery unit after passing through the condensation recovery unit, in other words, higher than the adsorption temperature of the adsorbent. Therefore, it is theoretically possible to use the exhaust heat of the dryer for heating and regeneration of the adsorbent.

  Therefore, the solvent recovery system uses at least a part of the heat contained in the exhaust of the dryer for heating and regeneration of the adsorbent that adsorbs and recovers the solvent vapor. Thereby, it is possible to reduce the heat energy necessary for heating and regeneration of the adsorbent, and to reduce the energy consumption of the entire system.

  The heat utilization unit regenerates at least a part of the heat medium that has passed through the condenser of the condensation recovery unit that cools the exhaust gas by heating and regenerating the adsorbent of the adsorption recovery unit that adsorbs and recovers the solvent vapor. The adsorbent may be directly or indirectly heated through a heater for heating, and then may be provided with a heat medium circulation path that flows again to the cooler.

  In the case of the solvent recovery system configured as described above, at least a part of the heat medium that has passed through the condenser of the condensation recovery unit that cools the exhaust of the dryer and condenses and recovers the solvent vapor is absorbed and recovered by the solvent vapor. The adsorbent is heated as it passes through a regenerative heater that heats and regenerates the material. Heating of the adsorbent may be performed directly by exchanging heat with the adsorbent by the heat medium that has passed through the condenser of the condensing recovery unit, or by exchanging heat with the gas sent to the adsorbent for heating regeneration. May be indirectly heated. Thereby, it is possible to reduce the heat energy necessary for heating and regeneration of the adsorbent, and to reduce the energy consumption of the entire system.

  The heating medium circulation path passes a heating medium between the cooler and a heater that heats the exhaust gas that passes through the condensation recovery unit and the adsorption recovery unit and is supplied again to the dryer. It is a heat medium circulation path that uses a part of the path to be circulated, a path that branches from the middle of the path that leads from the cooler to the heater, and that leads to the regeneration heater, and from the heater to the cooler And a path that joins from the regeneration heater to a connected path.

  In the solvent recovery system, since the adsorption recovery is performed after the condensation recovery, the thermal energy required for heating and regeneration of the adsorbent is smaller than the total thermal energy contained in the exhaust gas passing through the system. Thus, effective utilization of heat is achieved by circulating a heat medium between a cooler that cools the exhaust of the dryer and a heater that heats the exhaust of the dryer that is supplied again to the dryer after recovering the solvent vapor. By passing a part of the heat medium circulating in the circulation path through the regeneration heater, the heat energy required for the heat regeneration of the adsorbent can be reduced while reducing the heat energy consumed by the dryer. It is possible to reduce the energy consumption of the entire system.

  The regeneration heater heats a part of the exhaust gas from which the solvent vapor has been recovered by passing through the condensation recovery unit and the adsorption recovery unit, and sends the exhaust gas to the adsorbent. Heat regeneration may be used.

  If it is exhaust of the dryer which passed the condensation collection | recovery part and adsorption | suction collection | recovery part, the solvent vapor | steam is fully removed. Further, if the exhaust of the dryer that has passed through the adsorption recovery unit is heated and used for regeneration of the adsorbent, the adsorbent to be regenerated can be made higher than the adsorption temperature. Therefore, the adsorbent is efficiently heated and regenerated by heating a part of the exhaust gas from which the solvent vapor has been recovered by passing through the condensation recovery section and the adsorption recovery section, and sending it to the adsorbent. Consumption can be reduced.

In addition, after the heat utilization unit passes the part of the exhaust gas flowing from the dryer to the condensation recovery unit through a regeneration heater for heating and regenerating the adsorbent, the adsorbent is directly or indirectly heated. A branch path that flows to the condensation recovery unit may be used. With the solvent recovery system configured as described above, the energy consumption of the entire system can be reduced without providing a path through which the heat medium flows.

  In addition, the heat utilization part is provided in the middle of the branch path that branches in the middle of the path from the dryer to the condensing and collecting part, and in which a part of the exhaust gas flowing from the dryer flows to the condensing and collecting part. And a heat medium circulation path for circulating the heat medium between the heat exchanger and a regeneration heater that heats and regenerates the adsorbent. Even in the solvent recovery system configured as described above, since the thermal energy remaining in the exhaust of the dryer is used for heating and regeneration of the adsorbent, the energy consumption of the entire system can be reduced.

  If it is the said solvent collection | recovery system, it is possible to suppress the cost required for collection | recovery of the solvent vapor | steam in the gas supplied again to a dryer.

It is a block diagram of the solvent collection | recovery system which concerns on 1st embodiment. It is a block diagram of the solvent recovery system which an inventor assumes when not employ | adopting a heat recovery coil. It is the 1st graph which showed the energy reduction rate. It is the 2nd graph which showed the energy reduction rate. It is a block diagram of the solvent collection | recovery system which concerns on 2nd embodiment. It is a block diagram of the solvent collection | recovery system which concerns on the modification of 2nd embodiment.

  The configuration of the solvent recovery system according to the first embodiment of the present invention is shown in FIG. As shown in FIG. 1, the solvent recovery system 1 includes a condensation recovery device (corresponding to a condensation recovery portion in the present invention) 2 that condenses and recovers a solvent by cooling a predetermined gas containing solvent vapor with a coil, An adsorption / recovery device (corresponding to an adsorption / recovery unit in the present invention) 3 is provided that adsorbs and recovers the solvent remaining in the gas that has passed through the recovery device 2 with an adsorbent such as zeolite or activated carbon. In addition, the solvent recovery system 1 includes various fans for supplying gas, coils for performing heat exchange, piping and pumps for circulating water as a heat medium. The heat medium is not limited to water, and may be oil, brine, or other liquid.

  The solvent recovery system 1 is an apparatus that recovers solvent vapor in exhaust gas exhausted from production facilities that perform various chemical treatments with an organic solvent. In the present embodiment, description will be made on the assumption that NMP is recovered from high-temperature production exhaust gas containing N-methyl-2-pyrrolidone (hereinafter referred to as NMP) solvent vapor used in a lithium ion battery factory or the like. These solvents may also be used. Lithium ion battery factories use NMP when manufacturing electrodes. The NMP applied to the electrode is evaporated and exhausted by a dryer for drying the applied NMP.

  The solvent recovery system 1 according to this embodiment is an apparatus attached to such a dryer, and recovers the solvent vapor in the exhaust of the dryer. In the present embodiment, it is assumed that the exhaust temperature from a dryer that heats and drys various industrial products is about 100 ° C.

  As shown in FIG. 1, the condensing and recovering apparatus 2 has four heat exchange coils (reference numerals 4 to 7) arranged in series. Hereinafter, the heat recovery coil 4, the precooling coil 5, the main cooling coil 6, and the reheating coil 7 will be referred to in order from the upstream side.

The heat recovery coil 4 is connected to an air supply heating coil 8 provided on the downstream side of a fan 15A for supplying air to a dryer via a cooling water circulation system 11 constituted by pipes 11A and 11B. The heat recovery coil 4 cools the exhaust gas (hereinafter simply referred to as gas) sent from the dryer. The heat of the gas removed by the heat recovery coil 4 is transferred to the supply air heating coil 8 by the water circulating in the cooling water circulation system 11, purified by the condensation recovery device 2 and the adsorption recovery device 3, and sent to the dryer again. Heat. The gas at about 100 ° C. flowing into the heat recovery coil 4 reaches about 54 ° C. and is sent to the precooling coil 5. The gas that has passed through the supply air heating coil 8 is heated to about 70 ° C. and sent to the dryer.

  The precooling coil 5 further cools the gas cooled by the heat recovery coil 4. That is, the gas that has passed through the heat recovery coil 4 merges with the gas from the fan 15C that is the regeneration exhaust gas of the adsorption rotor 13, flows into the precooling coil 5, is cooled to about 29 ° C., and is sent to the main cooling coil 6. It is done. The pre-cooling coil 5 cools the gas with the cooling water of the cooling water circulation system having the cooling tower 10 in the path.

  The main cooling coil 6 further cools the gas cooled by the precooling coil 5. The main cooling coil 6 cools the gas with cooling water in a cooling water circulation system having a refrigerator 9 in the path. The main cooling coil 6 cools the gas at about 29 ° C. sent from the pre-cooling coil 5 to about 12 ° C. When the gas sent from the dryer is cooled to about 12 ° C. by the main cooling coil 6, NMP vapor is condensed on the surface of the cooling coil of the main cooling coil 6.

  The reheating coil 7 heats the gas cooled by the main cooling coil 6. In the reheating coil 7, the cooling water of the cooling water circulation system having the cooling tower 10 in the path flows, and heats the gas with the heat of the cooling water heated in the precooling coil 5. The reheating coil 7 heats the gas at about 12 ° C. sent from the main cooling coil 6 to about 27 ° C.

  The cooling water in the cooling water circulation system that flows through the pre-cooling coil 5, the reheating coil 7, and the cooling tower 10 follows the following path. That is, the cooling water cooled in the cooling tower 10 exits the cooling tower 10, passes through the reheating coil 7, and then returns to the cooling tower 10 through the precooling coil 5. Since the temperature of the gas flowing into the reheating coil 7 is about 12 ° C., the 32 ° C. cooling water flowing into the reheating coil 7 becomes about 19 ° C. after passing through the reheating coil 7 and flows into the precooling coil 5. Since the temperature of the gas flowing into the precooling coil 5 is about 55 ° C., the cooling water flowing into the precooling coil 5 reaches about 42 ° C. after passing through the precooling coil 5 and is sent again to the cooling tower 10. In addition, when the cooling tower 10 is integrated and operated with the cooling tower of another production facility, the cooling water of about 42 ° C. sent again to the cooling tower 10 is mixed with the cooling water of the other production facility. The return temperature of the cooling water returning to the cooling tower 10 is lower than 42 ° C.

  A certain amount of solvent is recovered by the condensing recovery device 2, and the gas whose temperature has been raised at the most downstream side is sent to the adsorption recovery device 3 for further purification. As shown in FIG. 1, the adsorption / recovery device 3 includes an adsorption rotor 13 and a regeneration coil 14 and is configured as follows.

  The adsorption rotor 13 carries an adsorbent that adsorbs solvent vapor inside a cylindrical member, and is a low temperature regeneration type adsorption rotor that can be regenerated at a temperature of about 100 ° C. or less. A section dividing cassette (not shown) is arranged on both end faces of the adsorption rotor 13, and the gas passage area of the adsorption rotor 13 is partitioned into a plurality of sections by this cassette. The suction rotor 13 is rotatable relative to the section division cassette, and a processing area and a regeneration area are formed in the suction rotor 13 by this cassette.

The gas at about 27 ° C. that has exited the condensation recovery device 2 passes through the processing region of the adsorption rotor 13. The treatment area adsorbs NMP in the gas to be vented and discharges the purified gas. Most of the gas exiting the processing area exits the solvent recovery system 1 and is sent to the dryer. A part of the gas exiting the processing area is sent to the regeneration area or exhausted out of the system. The gas exhausted to the outside of the system is appropriately replenished from a fresh air intake port (not shown) so that the gas circulating between the dryer and the solvent recovery system 1 is gradually replaced. That is, the solvent recovery system 1 does not process all the exhaust of the dryer and send it again to the dryer, but also incorporates some fresh air.

  A gas of about 80 ° C. heated by the regeneration coil 14 passes through the regeneration region of the adsorption rotor 13. The regeneration coil 14 heats the gas of about 30 ° C. sent to the regeneration region to about 80 ° C. after passing through the processing region of the adsorption rotor 13. The regeneration coil 14 is connected to a pipe 12 </ b> A that branches from the middle of the pipe 11 </ b> A that constitutes the cooling water circulation system 11, and high-temperature water that has exited the heat recovery coil 4 flows in the coil of the regeneration coil 14. The flow rate ratio at this branch point, that is, the flow rate ratio between the water flowing to the supply air heating coil 8 side after leaving the heat recovery coil 4 and the water flowing to the regeneration coil 14 side is the heat balance of the entire solvent recovery system 1. To be determined. That is, the flow rate is adjusted so as to substantially match the ratio of the amount of heat removed from the water in the supply air heating coil 8 and the amount of heat removed from the water in the regeneration coil 14. The amount of heat that water acquires in the heat recovery coil 4 and the amount of heat that is removed from the water in the supply air heating coil 8 and the regeneration coil 14 can be calculated based on the temperature difference and flow rate of water or gas in each coil. it can. The flow rate ratio may be kept constant with the flow rate ratio determined in the trial operation by a valve having a fixed opening degree, or the process value of the solvent recovery system 1 (for example, the exhaust temperature of the dryer, the exhaust air volume, etc.) is measured. The flow rate ratio may always be adjusted to an appropriate value by a valve that operates according to the opening determined based on the data.

  The water that has passed through the regeneration coil 14 flows through the pipe 12 </ b> B, joins the pipe 11 </ b> B constituting the cooling water circulation system 11, and flows again to the heat recovery coil 4. That is, the pipes 12A and 12B are used together with a part of the pipe 11B of the cooling water circulation system 11 so that the cooling water circulation system having the regeneration coil 14 and the heat recovery coil 4 in the path (the heat utilization part in the present invention). This is one embodiment and corresponds to the heat medium circulation path) 12. When the water heated to about 90 ° C. by the heat recovery coil 4 flows through the regeneration coil 14, the gas sent to the regeneration region side after passing through the treatment region of the adsorption rotor 13 is sufficiently heated, and approximately 80 It will reach ℃.

  The regeneration region is heated by the gas of about 80 ° C. heated by the regeneration coil 14 and sent to the regeneration region of the adsorption rotor 13, and the adsorbed solvent is released. The gas that has left the regeneration zone is sent again to the condensation recovery device 2. As a result, most of the solvent detached from the adsorption rotor 13 by regenerative heating is condensed and recovered by the main cooling coil 6 of the condensation recovery device 2.

  In the solvent recovery system 1 configured as described above, at least a part of the heat medium that has passed through the heat recovery coil 4 passes through the regeneration coil 14 that heats and regenerates the adsorbent of the adsorption rotor 13. For this reason, the thermal energy remaining in the exhaust of the dryer is effectively used, the thermal energy required for heating and regeneration of the adsorbent is reduced, and the energy consumption of the entire system is reduced. Moreover, since the maximum temperature of the water which flows through a cooling water circulation system is also about 100 degreeC, even if it does not perform the pressurization etc. to prevent a boiling, water can be utilized as a heat medium.

  In the solvent recovery system 1, the cooling water passing through the cooling tower 10 flows through the reheating coil 7 and the precooling coil 5 disposed before and after the main cooling coil 6, but the reheating coil 7 is omitted. The cooling water passing through the cooling tower 10 may flow only through the precooling coil 5. In this case, the outlet temperature of the refrigerator 9 is adjusted so that the exhaust of the dryer flowing into the adsorption region of the adsorption rotor 13 has a temperature of about 27 ° C. suitable for adsorption, or the cooling water circulation system having the refrigerator 9 is installed. It is desirable to adjust the flow rate.

FIG. 2 is a configuration diagram of the solvent recovery system 101 assumed by the inventor when the heat recovery coil 4 is not employed. In the solvent recovery system 101, the heat of the regeneration coil 14 is not the heat contained in the exhaust of the dryer, but the heat generated by the boiler 16. The adsorption rotor 13 is not a low-temperature regeneration type, but a general-type adsorption rotor that requires heating at about 130 ° C. or higher for regeneration. Since other configurations are the same as those of the solvent recovery system 1 according to the above-described embodiment, the same reference numerals are given and description thereof is omitted.

  The solvent recovery system 101 in FIG. 2 does not include the cooling water circulation system 12 provided in the solvent recovery system 1 according to the above-described embodiment because the heat source of the regeneration coil 14 is the boiler 16. For this reason, the solvent recovery system 101 in FIG. 2 cannot regenerate the adsorption rotor 13 using the heat contained in the exhaust of the dryer. Therefore, the energy consumption of the solvent recovery system 101 in FIG. 2 is compared with the energy consumption of the solvent recovery system 1 according to this embodiment as follows.

  FIG. 3 is a graph showing the energy consumption rate of the solvent recovery system 1 according to the present embodiment as an energy reduction rate from the energy consumption amount of the solvent recovery system 101 of FIG. The horizontal axis of the graph in FIG. 3 represents the ratio of the processing air volume (that is, the air volume of the fan 15A) to the regeneration air volume (that is, the air volume of the fan 15C). As is apparent from the graph of FIG. 3, when the heat of the regeneration coil 14 is changed from the heat generated in the boiler 16 to the heat contained in the exhaust of the dryer, the energy consumption of the entire system is 11% or less. It can be seen that it can be reduced by about 30% or more. Further, it can be seen from the graph of FIG. 3 that the effect of reducing the energy consumption increases as the ratio of the processing air volume to the regeneration air volume decreases.

  As apparent from the graph of FIG. 3, in the solvent recovery system 1 according to the present embodiment, the energy required for regeneration of the adsorption rotor 13 is reduced, so that the recovery of the solvent vapor in the gas supplied again to the dryer is performed. It is possible to greatly reduce the cost required for the process. Moreover, since the boiler equipment is unnecessary, the cost of the equipment can be suppressed.

  By the way, in the solvent recovery system 1 according to the present embodiment, the zone of the adsorption rotor 13 (ratio between the adsorption region and the regeneration region) of the solvent recovery system 101 of FIG. Although the reproduction can be performed at a low temperature by slowing the number, for example, the adsorbent material may be changed to a low-temperature regeneration type. Examples of such adsorbents include activated carbon and zeolite that can be regenerated at low temperatures, and polymer adsorbents that can be regenerated at low temperatures.

  In the solvent recovery system 1 according to the above embodiment, the gas at about 100 ° C. exhausted from the dryer is cooled to about 54 ° C. by the heat recovery coil and cooled to about 29 ° C. by the precooling coil 5. It is cooled to about 12 ° C. by the main cooling coil 5. Then, it is heated to about 27 ° C. by the reheating coil 7 and heated to about 70 ° C. by the supply air heating coil 8. However, the solvent recovery system 1 may be modified to have the following process values, for example, by appropriately changing the flow rate of the cooling water and the specifications of the coil.

  That is, in the solvent recovery system 1 according to the modified example, for example, after the gas of about 100 ° C. exhausted from the dryer is cooled to about 49 ° C. by the heat recovery coil and cooled to about 34 ° C. by the pre-cooling coil 5, The main cooling coil 5 may cool to about 12 ° C. Then, it may be heated to about 20 ° C. by the reheating coil 7 and heated to about 70 ° C. by the supply air heating coil 8.

  FIG. 4 is a graph showing the energy consumption rate of the solvent recovery system 1 according to this modification as an energy reduction rate from the energy consumption rate of the solvent recovery system 101 of FIG. As is apparent from the graph of FIG. 4, when the heat of the regeneration coil 14 is changed from the heat generated in the boiler 16 to the heat contained in the exhaust of the dryer, the energy consumption of the entire system is 11 or less. It can be seen that it can be reduced by about 27% or more.

  FIG. 5 is a configuration diagram of the solvent recovery system 21 according to the second embodiment. The solvent recovery system 21 is basically the same as the solvent recovery system 1 according to the first embodiment, except that the regeneration coil 14 is not a water-to-air heat exchanger but an air-to-air heat exchanger. A part of the gas that is exhausted from the exhaust gas and flows to the heat recovery coil 4 passes through the regeneration coil 14 to heat the gas sent to the regeneration region side after passing through the processing region of the adsorption rotor 13. Yes. That is, the solvent recovery system 21 heats the gas sent to the regeneration area side after passing through the treatment area of the adsorption rotor 13 by the exhaust of the dryer.

  More specifically, the regeneration coil 14 of the solvent recovery system 21 includes a duct 22 </ b> A that branches from the middle of the path connecting the dryer and the heat recovery coil 4, and a middle path of the path connecting the heat recovery coil 4 to the precooling coil 5. It is provided in the middle of a gas branch path 22 (which is an aspect of the heat utilization section referred to in the present invention) constituted by the duct 22B that merges, and branches from the middle of the path that connects the dryer and the heat recovery coil 4. The gas sent to the regeneration region side after passing through the treatment region of the adsorption rotor 13 is heated by the heat contained in the exhaust of the dryer. The solvent recovery system 21 omits the cooling water circulation system 12 provided in the solvent recovery system 1. About another structure, it is the same as that of the solvent collection | recovery system 1. FIG.

  With the solvent recovery system 21 configured as described above, the thermal energy necessary for heating and regeneration of the adsorbent is covered by the thermal energy remaining in the exhaust of the dryer, so that the energy consumption of the entire system is reduced. Further, although the ducts 22A and 22B are bulky, there is less risk of water leakage or the like as compared with the case where the cooling water circulation system 12 through which water circulates is provided, so that reliability can be ensured even when the dryer is a water-restricted area. Further, since the exhaust gas that has passed through the regeneration coil 14 is sent to the precooling coil 5 through the duct 22B, the gas contaminated by the solvent vapor is not sent to the dryer.

  The solvent recovery system 21 is configured such that a part of the exhaust of the dryer branched by the duct 22A from the middle of the path connecting the dryer and the heat recovery coil 4 directly passes through the regeneration coil 14, so that the adsorption rotor 13 Rather than heating the gas sent to the regeneration region after passing through the treatment region, for example, the heat of the gas flowing through the branch path 22 is indirectly transmitted to the regeneration coil 14 via a heat medium such as water. It may be. A solvent recovery system 21 'according to such a modification is shown in FIG.

  As shown in FIG. 6, the solvent recovery system 21 ′ according to the present modification includes an air-to-water heat exchanger 23 in the middle of the branch path 22. And the heat exchanger 23 and the reproduction | regeneration coil 14 are connected by the water circulation path | route 24 comprised by piping 24A, 24B. Thereby, the heat contained in the exhaust of the dryer flowing through the branch path 22 is transferred to the water, which is the heat medium of the water circulation path 24, through the heat exchanger 23, and after passing through the processing area of the adsorption rotor 13, the regeneration area side It is transmitted to the gas sent to through the regeneration coil 14. As a result, the thermal energy remaining in the exhaust of the dryer is used for heating and regeneration of the adsorbent, and the energy consumption of the entire system is reduced.

1, 21 ·· Solvent recovery system 2 · Condensation recovery device 3 · Adsorption recovery device 11, 12 · · Cooling water circulation system 22 · · Branch path

Claims (6)

A solvent recovery system for supplying the drying chamber exhaust for recovering the solvent vapor evaporated in the drying chamber to a drying chamber of a dryer for drying an object coated with a solvent,
A condensation recovery unit that cools the exhaust and condenses and recovers the solvent vapor contained in the exhaust;
An adsorption recovery unit that adsorbs and recovers the solvent vapor remaining in the exhaust gas that has passed through the condensation recovery unit;
A heat utilization unit that utilizes at least part of the heat contained in the exhaust of the dryer to heat and regenerate the adsorbent of the adsorption recovery unit that adsorbs and recovers the solvent vapor,
Solvent recovery system. The heat utilization part is a heating for regeneration that heats and regenerates the adsorbent of the adsorption recovery part that adsorbs and recovers the solvent vapor, at least part of the heat medium that has passed through the condenser of the condensation recovery part that cools the exhaust gas. A heating medium circulation path that directly or indirectly heats the adsorbent through a vessel and then flows to the cooler again,
The solvent recovery system according to claim 1. The heat medium circulation path circulates the heat medium between the cooler and a heater that heats the exhaust gas that passes through the condensation recovery unit and the adsorption recovery unit and is supplied again to the dryer. A heating medium circulation path that uses a part of the path, a path that branches from the middle of the path that leads from the cooler to the heater, and that leads to the regeneration heater, and a path that leads from the heater to the cooler A path for joining from the regeneration heater,
The solvent recovery system according to claim 2. The regeneration heater heats a part of the exhaust gas from which the solvent vapor has been recovered by passing through the condensation recovery unit and the adsorption recovery unit, and sends the exhaust gas to the adsorbent, thereby heating and regenerating the adsorbent. Let
The solvent recovery system according to claim 2 or 3. The heat utilization unit passes a part of the exhaust gas flowing from the dryer to the condensation recovery unit through a regeneration heater that heats and regenerates the adsorbent, and directly or indirectly heats the adsorbent, It has a branch path that flows to the condensing recovery part
The solvent recovery system according to claim 1. The heat utilization part branches in the middle of a path leading from the dryer to the condensation recovery part, a branch path for passing a part of the exhaust gas flowing from the dryer to the condensation recovery part, and heat provided in the middle of the branch path A heating medium circulation path for circulating a heating medium between the exchanger and a regeneration heater for heating and regenerating the adsorbent,
The solvent recovery system according to claim 1.

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