Vacuum condensation dryer

Abstract

A vacuum condensation dryer is disclosed. The vacuum condensation dryer may include: a dryer for drying and discharging a material containing a solvent by heat exchange between a heating medium and the material and discharging an evaporated solvent evaporated during the drying process; a condenser for receiving the evaporation solvent from the dryer by means of an evaporation solvent line, condensing the evaporation solvent into a condensed solvent by means of heat exchange with a refrigerant, and discharging the condensed refrigerant; a heat pump for circulating a heat exchange medium to collect thermal energy from the refrigerant through heat exchange between the heat exchange medium and the refrigerant, and to supply the collected thermal energy to the heating medium through heat exchange between the heat exchange medium and the heating medium; a vacuum pump connected to the condenser for reducing the pressure inside the condenser and discharging non-condensable gas generated during the solvent condensation process; and a heating medium tank provided on a line connecting the heat pump and the dryer and including a heating medium heating device for heating a heating medium for supplying the heated heating medium to the line.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application Nos. 10-2023-0087082 and 10-2023-0091289 filed on July 5, 2023 and July 13, 2023, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.

[0003] The present disclosure relates to a vacuum condensation dryer. In more detail, an exemplary embodiment of the present disclosure relates to a vacuum condensation dryer equipped with a heat pump, which recovers latent heat generated in the condensation of an evaporated solvent in a condenser and supplies the recovered latent heat to the dryer, thereby reducing the energy used to dry raw materials and minimizing carbon emissions. Another exemplary embodiment of the present disclosure relates to a vacuum condensation dryer, which can minimize the flow of non-condensable external air into the dryer by preheating the raw materials and supplying the raw materials to the dryer. Background Art

[0004] In the chemical industry, a granular product (e.g., a dried material) is produced by obtaining granules containing moisture (e.g., a raw material) by chemical reaction or other methods and drying the granules containing moisture in a dryer. As dryers commonly used for drying granules in the chemical industry, there are fluidized bed dryers and indirect heating vacuum condensation dryers.

[0005] The fluidized bed dryer is configured to dry the product in the dryer using hot air supplied into the dryer. In detail, the product in the dryer is fluidized by blowing hot air into the dryer, while the energy required for the evaporation of the solvent (moisture) is supplied, and the evaporated solvent and hazardous substances / harmful substances are discharged to the post-processing equipment together with the hot air. However, since the fluidized bed dryer uses strong hot air, fine particles may be scattered, and therefore, there is a risk of dust explosion. In addition, stagnant areas are generated, so hot spots may be formed, and there is a risk of fire due to the high-temperature hot air. In addition, since a small amount of hazardous substances / harmful substances generated during drying is discharged with a large amount of hot air, the capacity of the post-processing equipment increases, the post-processing cost increases, only some of the energy supplied by the hot air is used to dry the product, and the other energy is wasted as exhaust gas, so the energy efficiency is low.

[0006] The indirect heating vacuum condensation dryer is configured to use a heat transfer fluid flowing through a jacket in the dryer to dry the product outside the jacket. In detail, the product is dried by supplying a heat transfer fluid into the jacket in the dryer, the evaporated solvent is condensed by the condenser and then discharged, and some non-condensable gases are discharged to the vacuum pump. The vacuum pump is connected to the condenser and the dryer, and the saturation pressure and drying temperature of the solvent (water) in the dryer can be reduced. However, the indirect heating vacuum condensation dryer must independently supply the energy for drying the product and the energy for condensing the solvent, so the overall energy efficiency is low.

[0007] At the same time, the vacuum condensation dryer can be divided into an intermittent vacuum condensation dryer and a continuous vacuum condensation dryer.

[0008] The intermittent vacuum condensation dryer has an inlet and an outlet that can be opened and closed. The user opens the inlet, puts a set amount of raw material into the dryer, closes the inlet, and then starts drying. When the drying of the raw material is completed, the user opens the outlet, and the dried material can be discharged from the dryer. However, the intermittent vacuum condensation dryer can only dry a set amount of raw material at a time, and it is impossible to additionally supply raw materials during drying, so the capacity of the dryer must be increased to increase the drying amount.

[0009] In a continuous vacuum condensation dryer, the supply of raw materials, the drying of raw materials, and the discharge of dried materials are carried out in a continuous manner. That is, the raw materials are continuously supplied to the continuous vacuum condensation dryer, the supplied raw materials are moved to the outlet while being dried in the dryer, and the dried materials are also continuously discharged. Since the supply of raw materials, the drying of raw materials, and the discharge of dried materials are carried out in a continuous manner, the drying amount can be increased even without increasing the capacity of the continuous vacuum condensation dryer. However, since non-condensable external air also flows into the dryer when the raw materials are supplied to the dryer, it affects the vacuum degree inside the dryer, thereby it may deteriorate the drying performance and may increase the flow rate of non-condensable gases to the vacuum pump or post-processing equipment. Therefore, it is necessary to increase the capacity of the vacuum pump to maintain the vacuum degree inside the dryer, and the energy used in the vacuum pump or post-processing equipment increases.

[0010] This background is provided to help understand the context of the disclosure and may include content of related fields that are not known to those skilled in the art. Summary of the invention

[0011] Technical issues

[0012] The present disclosure seeks to provide a vacuum condensation dryer equipped with a heat pump capable of reducing energy used for drying raw materials and minimizing carbon emissions by using a heat pump that recovers latent heat generated when evaporated solvent is condensed in a condenser and supplies the recovered latent heat to the dryer.

[0013] In addition, the present disclosure attempts to provide a vacuum condensation dryer, which can operate smoothly without a specific heat source or cooling source when being restarted by including a heat transfer fluid tank having a heat transfer fluid heater and arranged in a heat transfer fluid supply pipeline or a refrigerant tank having a refrigerant cooler and arranged in the refrigerant supply pipeline.

[0014] In addition, the present disclosure seeks to provide a vacuum condensation dryer including a raw material preheater which is located at a more upstream side than the dryer and preheats a raw material supplied into the dryer.

[0015] Technical Solution

[0016] According to an exemplary embodiment of the present disclosure, a vacuum condensation dryer includes: a dryer configured to dry and discharge a raw material containing a solvent through heat exchange between the raw material and a heat transfer fluid, and to discharge the evaporated solvent evaporated during the drying process; a condenser configured to receive the evaporated solvent from the dryer through an evaporated solvent pipeline, condense the evaporated solvent into a condensed solvent through heat exchange with a refrigerant, and discharge the condensed refrigerant; a heat pump configured to recover heat energy from the refrigerant by circulating a heat exchange medium, through heat exchange between the heat exchange medium and the refrigerant, and supply the recovered heat energy to the heat transfer fluid through heat exchange with the heat exchange medium; a vacuum pump connected to the condenser and configured to reduce the pressure inside the condenser and discharge non-coolable solvent generated during the condensation process of the solvent condensable gas; a heat transfer fluid supply pipeline, the heat transfer fluid supply pipeline being configured to supply the heat transfer fluid supplied with thermal energy from the heat pump to the dryer; a heat transfer fluid recovery pipeline, the heat transfer fluid recovery pipeline being configured to recover the heat transfer fluid having undergone heat exchange with the raw material from the dryer to the heat pump; a refrigerant supply pipeline, the refrigerant supply pipeline being configured to supply the refrigerant having undergone heat exchange with the heat exchange medium from the heat pump to the condenser; a refrigerant recovery pipeline being configured to recover the refrigerant having recovered thermal energy from the evaporating solvent from the condenser to the heat pump; and a heat transfer fluid tank being disposed on the heat transfer fluid supply pipeline or the heat transfer fluid recovery pipeline, the heat transfer fluid tank including a heat transfer fluid heater for heating the heat transfer fluid and being configured to supply the heated heat transfer fluid to the heat transfer fluid supply pipeline or the heat transfer fluid recovery pipeline.

[0017] A heat transfer fluid heater may be provided on the heat transfer fluid supply line to supply heated heat transfer fluid to the dryer through the heat transfer fluid supply line.

[0018] The vacuum condensation dryer may further include a refrigerant tank disposed on the refrigerant supply line or the refrigerant recovery line, the refrigerant tank including a refrigerant cooler cooling the refrigerant and configured to supply the cooled refrigerant to the refrigerant supply line or the refrigerant recovery line.

[0019] A refrigerant cooler may be provided on the refrigerant supply line to supply cooled refrigerant to the condenser through the refrigerant supply line.

[0020] The heat transfer fluid heater or the refrigerant cooler can be controlled to operate when the vacuum condensation dryer is stopped.

[0021] The heat transfer fluid heater may be operated so that the temperature of the heat transfer fluid becomes a set heat transfer fluid temperature or higher, or the refrigerant cooler may be operated so that the temperature of the refrigerant becomes a set refrigerant temperature or lower.

[0022] The heat pump may include: a heat exchange medium circulation pipeline, through which the heat exchange medium circulates; a first heat exchanger, which is arranged on the heat exchange medium circulation pipeline and is configured to supply heat energy to the heat transfer fluid through heat exchange between the heat transfer fluid and the heat exchange medium; an expansion valve, which is arranged on the heat exchange medium circulation pipeline and expands the heat exchange medium that has exchanged heat with the heat transfer fluid; a second heat exchanger, which is arranged on the heat exchange medium circulation pipeline and is configured to recover the heat energy of the refrigerant through heat exchange between the refrigerant and the heat exchange medium; and a compressor, which is arranged on the heat exchange medium circulation pipeline and compresses the heat exchange medium that has exchanged heat with the refrigerant.

[0023] The vacuum condensation dryer may further include a recovery tank connected to the condenser via a condensation solvent line and receiving the condensation solvent of the condenser, wherein a vacuum pump may be connected to the recovery tank via a non-condensable gas recovery line to discharge non-condensable gases in the condenser and the recovery tank.

[0024] The vacuum condensation dryer may further include a raw material preheater configured to continuously receive and preheat the raw material containing the solvent and to continuously discharge the preheated raw material containing the solvent, wherein the dryer may continuously receive and dry the preheated raw material containing the solvent from the raw material preheater.

[0025] The raw material preheater may include a preheat housing, and the preheat housing may be configured to transfer heat to the raw material including the solvent therein.

[0026] The dryer may include: a dryer shell; a raw material inlet formed at an upper portion of one side portion of the dryer shell; a raw material outlet formed at a lower portion of another side portion of the dryer shell; and a screw rotatably disposed in the dryer shell, and raw material containing a solvent can be supplied into the dryer shell through the raw material inlet, the raw material containing a solvent can be dried while the rotating screw is moved to the other side portion of the dryer shell, and the dried raw material can be discharged from the dryer shell through the raw material outlet.

[0027] The dryer may also include: a heat transfer fluid inlet formed on one side of the dryer shell; and a heat transfer fluid outlet formed on the other side of the dryer shell, and the heat transfer fluid flowing into the dryer through the heat transfer fluid inlet can exchange heat with the raw material containing the solvent while moving to the other side, and can flow out of the dryer through the heat transfer fluid outlet.

[0028] Beneficial Effects

[0029] According to an exemplary embodiment of the present disclosure, energy for drying raw materials and carbon emissions may be reduced using a heat pump that recovers latent heat generated in condensation of an evaporated solvent in a condenser and supplies the recovered latent heat to a dryer.

[0030] Furthermore, since the heat transfer fluid heater heats the heat transfer fluid or the refrigerant cooler cools the refrigerant when the vacuum condensation dryer is stopped, a sufficient amount of heat can be supplied for drying or recovered for condensation even without a high-output heating facility or cooling facility at the time of restarting. Therefore, changes in productivity and quality in the early stage of drying can be minimized.

[0031] According to another exemplary embodiment of the present disclosure, the raw material supplied to the dryer can be preheated by including a raw material preheater at a more upstream side than the dryer. The partial pressure of the non-condensable gas can be reduced by increasing the partial pressure of the condensable solvent, and therefore, the necessity of increasing the capacity of the vacuum pump can be reduced by reducing the flow rate of the non-condensable gas flowing into the dryer.

[0032] Other effects that can be obtained or predicted by the exemplary embodiment will be explicitly or implicitly described in the detailed description of the exemplary embodiment. That is, various effects predicted according to the exemplary embodiment will be described in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The exemplary embodiments of the present specification may be better understood by referring to the following description in conjunction with the drawings, wherein like reference numbers indicate identical or functionally similar elements.

[0034] Figure 1 is a schematic diagram of a vacuum condensation dryer according to an exemplary embodiment of the present disclosure.

[0035] Figure 2 yes Figure 1 Schematic diagram of a heat pump.

[0036] Figure 3 is a schematic diagram of a vacuum condensation dryer according to another exemplary embodiment of the present disclosure.

[0037] Figure 4 It is schematically shown Figure 3 View of the preheater.

[0038] It should be understood that the drawings referred to above are not necessarily drawn to scale, but rather present a rather simplified representation of various preferred features that illustrate the basic principles of the present disclosure. For example, the specific design features of the present disclosure, including specific dimensions, directions, locations, and shapes, will be determined in part by the specific intended application and use environment. DETAILED DESCRIPTION

[0039] The terms used herein are only for the purpose of describing specific exemplary embodiments, and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "including" and / or "including" specify the existence of the quoted features, integers, steps, operations, elements and / or parts when used in this article, but it will also be understood that these terms do not exclude the existence or addition of one or more other features, integers, steps, operations, elements, parts and / or their combinations. As used herein, the term "and / or" includes any one or all combinations of the items listed in the relevant.

[0040] In addition, it should be understood that one or more of the following methods or aspects thereof can be performed by at least one or more controllers. The term "controller" can refer to a hardware device including a memory and a processor. The memory is configured to store program instructions, and the processor is specifically programmed to execute program instructions to perform one or more processes described in more detail below. The controller can control the operation of a unit, module, component, device, etc., as described herein. It should also be understood that, as will be understood by those skilled in the art, the following methods can be performed by a device including a controller in combination with one or more other components.

[0041] In addition, the controller of the present disclosure may be implemented as a non-transitory computer-readable recording medium including executable program instructions executed by a processor. Examples of computer-readable recording media include ROM, RAM, compact disk (CD) ROM, tape, floppy disk, flash drive, smart card, and optical data storage device, but are not limited thereto. The computer-readable recording medium may also be distributed throughout a computer network so that program instructions may be stored and executed in a distributed manner, for example, on a telematics server or a controller area network (CAN).

[0042] According to the present disclosure, a vacuum condensation dryer includes: a dryer that dries a raw material and evaporates a solvent by heat exchange with a heat transfer fluid, and the dryer discharges the evaporated solvent; a condenser that condenses the evaporated solvent by heat exchange with a refrigerant; and a heat pump that recovers heat energy from the refrigerant by circulating a heat exchange medium and supplies the recovered heat energy to the heat transfer fluid. The heat energy recovered from the refrigerant in the condenser is used as at least a part of the heat energy required for solvent evaporation in the dryer, thereby improving energy efficiency.

[0043] In addition, the vacuum condensation dryer further includes: a heat transfer fluid supply line, which supplies the heat transfer fluid from the heat pump to the dryer; a heat transfer fluid recovery line, which recovers the heat transfer fluid from the dryer to the heat pump; a refrigerant supply line, which supplies the refrigerant from the heat pump to the condenser; a refrigerant recovery line, which recovers the refrigerant from the condenser to the heat pump; a heat transfer fluid tank, which includes a heat transfer fluid heater disposed in the heat transfer fluid supply line or the heat transfer fluid recovery line and heats the heat transfer fluid; or a refrigerant tank, which includes a refrigerant cooler disposed in the refrigerant supply line or the refrigerant recovery line and cools the refrigerant. When the vacuum condensation dryer is stopped, the heat transfer fluid heater heats the heat transfer fluid or the refrigerant cooler cools the refrigerant. When the vacuum condensation dryer is restarted, the heat energy or cooling energy required for normal operation can be prepared by a low output heating facility or a cooling facility. Therefore, when the vacuum condensation dryer is restarted, a sufficient amount of heat can be supplied for drying or a sufficient amount of heat can be recovered for condensation even without a high-output heating facility or cooling facility. Therefore, changes in productivity and quality can be minimized in the early stages of drying.

[0044] In addition, the vacuum condensation dryer also includes: a vacuum pump connected to the condenser and configured to reduce the pressure inside the condenser and discharge the non-condensable gas generated during the condensation of the solvent; and a recovery tank connected to the condenser and receiving the condensed solvent from the condenser. The vacuum pump is connected to the condenser through the recovery tank, and discharges the non-condensable gas in the condenser and the recovery tank. The vacuum pump is connected to the dryer through an evaporation solvent pipeline connecting the dryer and the condenser, and can not only reduce the pressure inside the condenser, but also reduce the pressure inside the dryer. Therefore, the saturation pressure and drying temperature of the solvent in the dryer can be reduced. Therefore, even by an indirect heating type, the raw materials in the dryer can be fully dried.

[0045] In addition, the vacuum condensation dryer also includes a raw material preheater, which is configured to continuously receive and preheat the raw material containing the solvent and continuously discharge the preheated raw material containing the solvent, and the dryer is configured to continuously receive and dry the preheated raw material containing the solvent from the raw material preheater. The raw material preheater can increase and decrease the partial pressure of the condensable solvent and the partial pressure of the non-condensable gas supplied to the dryer together with the raw material by preheating the raw material containing the solvent. Therefore, the reduction in the vacuum degree of the dryer can be minimized by reducing the flow rate of the non-condensable gas flowing into the dryer, and there is no need to increase the capacity of the vacuum pump in order to maintain the vacuum degree. In addition, the flow rate of the non-condensable gas to the vacuum pump can be reduced by reducing the inflow of the non-condensable gas into the dryer, thereby further reducing the energy consumed by the vacuum pump and the post-processing equipment.

[0046] Hereinafter, exemplary embodiments of the present disclosure are described in detail with reference to the accompanying drawings.

[0047] Figure 1 is a schematic diagram of a vacuum condensation dryer according to an exemplary embodiment of the present disclosure. Figure 2 yes Figure 1 Schematic diagram of a heat pump.

[0048] like Figure 1 As shown in , the vacuum condensation dryer 10 according to an exemplary embodiment of the present disclosure includes a dryer 20 , a condenser 50 , and a heat pump 40 .

[0049] The dryer 20 is configured to dry the raw material and evaporate the solvent by heat exchange with the heat transfer fluid, and is configured to discharge the evaporated solvent. The dryer 20 includes a dryer housing 21, in which a drying space is formed. A raw material inlet 22 is formed at an upper portion of one side portion of the dryer housing 21, so that the raw material containing the solvent to be dried is supplied to the drying space in the dryer housing 21 through the raw material inlet 22. A raw material outlet 24 is formed at a lower portion of the other side portion of the dryer housing 21, so that the dried raw material is discharged from the dryer housing 21 through the raw material outlet 24.

[0050] In addition, a heat transfer fluid inlet 30 is formed at one side of the dryer housing 21, so that the hot heat transfer fluid for drying flows into the dryer housing 21 through the heat transfer fluid inlet 30. A heat transfer fluid outlet 32 ​​is formed at the other side of the dryer housing 21, so that, in particular, the heat transfer fluid that has exchanged heat with the solvent contained in the raw material flows out of the dryer housing 21 through the heat transfer fluid outlet 32. A jacket or the like is formed in the dryer housing 21, so that the heat transfer fluid that flows into the dryer housing 21 through the heat transfer fluid inlet 30 moves through the jacket and does not directly contact the raw material in the dryer housing 21. That is, the dryer 20 according to the exemplary embodiment of the present disclosure uses an indirect heating type that uses the movement of the heat transfer fluid in the jacket or the like to heat and dry the raw material. Therefore, in the dryer, fine particles may not be dispersed, reducing the risk of dust explosion, and no hot spot is formed, which can reduce the risk of fire.

[0051] A screw 26 is rotatably provided in the dryer housing 21, and at least one thread 28 is formed on the outer circumferential surface of the screw 26. The screw 26 moves the raw material from one side to the other side while rotating in the dryer housing 21. Therefore, the heat energy of the heat transfer fluid can be uniformly transferred to the raw material conveyed by the screw 26.

[0052] An evaporation solvent outlet 39 connected to the evaporation solvent line 38 is formed at an upper portion of the other side portion of the dryer housing 21 , and the evaporation solvent evaporated by heat exchange with the heat transfer fluid in the dryer housing 21 flows out to the evaporation solvent line 38 through the evaporation solvent outlet 39 .

[0053] The condenser 50 is configured to condense the evaporated solvent from the dryer 20 by heat exchange with the refrigerant, and discharge the condensed condensed solvent and non-condensable gas. The condenser 50 includes a condenser housing 51 in which a condensation space is formed. An evaporated solvent inlet 56 connected to the evaporated solvent line 38 is formed at the upper portion of the condenser housing 51, so the evaporated solvent evaporated in the dryer 20 flows into the condensation space in the condenser housing 51 through the evaporated solvent line 38 and the evaporated solvent inlet 56. A condensed solvent outlet 58 is formed at the lower portion of the condenser housing 51, so the condensed solvent condensed by heat exchange with the refrigerant in the condenser housing 51 flows out of the condenser housing 51 through the condensed solvent outlet 58. In addition, a refrigerant supply line 54 is connected to one side of the condenser housing 51, so the cold refrigerant for the condensed solvent flows into the condenser housing 51 through the refrigerant supply line 54. A refrigerant recovery line 52 is connected to the other side of the condenser shell 51, so the refrigerant that recovers heat energy by heat exchange with the evaporated solvent flows out of the condenser shell 51 through the refrigerant recovery line 52. A jacket or the like is formed in the condenser shell 51, so the refrigerant that flows into the condenser shell 51 through the refrigerant supply line 54 moves through the jacket and does not directly contact the solvent in the condenser shell 51.

[0054] The heat pump 40 is configured to recover heat energy from the refrigerant and supply the recovered heat energy to the heat transfer fluid by circulating the heat exchange medium. Figure 1 and Figure 2 As shown in FIG. 4 , the heat pump 40 includes a heat exchange medium circulation pipeline 42 , a first heat exchanger 43 and a second heat exchanger 45 , an expansion valve 44 and a compressor 46 .

[0055] The heat exchange medium circulation pipeline 42 connects the first heat exchanger 43 , the expansion valve 44 , the second heat exchanger 45 and the compressor 46 , so that the heat exchange medium circulates through the first heat exchanger 43 , the expansion valve 44 , the second heat exchanger 45 and the compressor 46 in sequence.

[0056] The first heat exchanger 43 is provided on the downstream side of the compressor 46 on the heat exchange medium circulation line 42, and transfers heat energy to the heat transfer fluid by heat exchange between the heat exchange medium circulating through the heat exchange medium circulation line 42 and the heat transfer fluid. The first heat exchanger 43 is connected to the heat transfer fluid supply line 34, so that the heat transfer fluid supplied with heat energy by heat exchange with the heat exchange medium is supplied to the dryer 20. In addition, the first heat exchanger 43 is connected to the heat transfer fluid recovery line 36, so that the heat transfer fluid that has exchanged heat with the raw material is recovered from the dryer 20. The heat transfer fluid supply line 34 and the heat transfer fluid recovery line 36 are connected to each other in the first heat exchanger 43.

[0057] The expansion valve 44 is provided on the downstream side of the first heat exchanger 43 on the heat exchange medium circulation line 42, and expands the heat exchange medium supplying heat energy to the heat transfer fluid in the first heat exchanger 43, thereby lowering the temperature of the heat exchange medium.

[0058] The second heat exchanger 45 is provided on the downstream side of the expansion valve 44 on the heat exchange medium circulation line 42, and recovers heat energy of the refrigerant by heat exchange between the heat exchange medium whose temperature is reduced by expansion in the expansion valve 44 and the refrigerant. The heat energy recovered from the refrigerant in the second heat exchanger 45 is transferred to the heat transfer fluid in the first heat exchanger 43, thereby being used for drying the raw material. Therefore, the amount of energy required for drying the raw material supplied from the outside can be reduced.

[0059] The second heat exchanger 45 is connected to the refrigerant supply line 54, so the refrigerant whose temperature is reduced by heat exchange with the heat exchange medium is supplied to the condenser 50. In addition, the second heat exchanger 45 is connected to the refrigerant recovery line 52, so the refrigerant that recovers heat energy by heat exchange with the evaporated solvent is recovered from the condenser 50. The refrigerant supply line 54 and the refrigerant recovery line 52 are connected to each other in the second heat exchanger 45.

[0060] The compressor 46 is provided on the downstream side of the second heat exchanger 45 on the heat exchange medium circulation line 42, and compresses the heat exchange medium that recovers heat energy from the refrigerant in the second heat exchanger 45, thereby raising the temperature of the heat exchange medium. The heat exchange medium compressed in the compressor 46 moves to the first heat exchanger 43 and circulates through the heat exchange medium circulation line 42.

[0061] Refer again Figure 1 The vacuum condensation dryer 10 further includes a heat transfer fluid tank 100 and a refrigerant tank 110 .

[0062] The heat transfer fluid tank 100 is disposed on the heat transfer fluid supply line 34 or the heat transfer fluid recovery line 36, temporarily stores the heat transfer fluid of the heat transfer fluid supply line 34 or the heat transfer fluid recovery line 36, and supplies the stored heat transfer fluid to the heat transfer fluid supply line 34 or the heat transfer fluid recovery line 36. In one example, the heat transfer fluid tank 100 is disposed on the heat transfer fluid supply line 34 and includes a heat transfer fluid heater 105 disposed therein. The heat transfer fluid heater 105 heats the heat transfer fluid in the heat transfer fluid tank 100, and the heated heat transfer fluid can be supplied to the dryer 20 through the heat transfer fluid supply line 34 when the vacuum condensation dryer 10 is started or operated.

[0063] The refrigerant tank 110 is disposed on the refrigerant supply line 54 or the refrigerant recovery line 52, temporarily stores the refrigerant of the refrigerant supply line 54 or the refrigerant recovery line 52, and supplies the stored refrigerant to the refrigerant supply line 54 or the refrigerant recovery line 52. In one example, the refrigerant tank 110 is disposed on the refrigerant supply line 54 and includes a refrigerant cooler 115 disposed therein. The refrigerant cooler 115 cools the refrigerant in the refrigerant tank 110, and the cooled refrigerant can be supplied to the condenser 50 through the refrigerant supply line 54 when the vacuum condensation dryer 10 is started or operated.

[0064] The vacuum condensation dryer 10 may further include a controller (not shown). The controller is connected to the heat transfer fluid heater 105 and / or the refrigerant cooler 115 and controls the heat transfer fluid heater 105 and / or the refrigerant cooler 115. In one example, when the vacuum condensation dryer 10 stops, the controller controls the heat transfer fluid heater 105 to heat the heat transfer fluid, or controls the refrigerant cooler 115 to cool the refrigerant. When the vacuum condensation dryer 10 is restarted or during early operation, the operation of the heat pump 40 alone may not be enough to dry the raw material or condense the solvent. In order to solve this problem, in the early stage of drying, a high output heating facility or cooling facility that can supply enough heat energy or cooling energy has been adopted for normal operation. However, according to an exemplary embodiment of the present disclosure, when the vacuum condensation dryer 10 stops, the heat transfer fluid heater 105 keeps the temperature of the heat transfer fluid above the set heat transfer fluid temperature by heating the heat transfer fluid, or the refrigerant cooler 115 keeps the temperature of the refrigerant below the set refrigerant temperature by cooling the refrigerant. Therefore, even when there is no high-output heating facility or cooling facility when the vacuum condensation dryer 10 is restarted or during early operation, a sufficient amount of heat can be supplied for drying or a sufficient amount of heat can be recovered for condensation. Therefore, changes in productivity and quality in the early stage of drying can be minimized.

[0065] The vacuum condensation dryer 10 further includes a vacuum pump 90 and recovery tanks 80 and 85 . Figure 1 exemplarily shows the vacuum condensation dryer 10 including two recovery tanks 80 and 85 , but the number of the recovery tanks is not limited to two, and one or more recovery tanks may be used.

[0066] The first recovery tank 80 is connected to the condenser 50 through the first condensed solvent line 60. Therefore, the condensed solvent condensed in the condenser 50 and the non-condensable gas that is not condensed are discharged to the first recovery tank 80 through the first condensed solvent line 60.

[0067] The second recovery tank 85 is connected to the first recovery tank 80 through the second condensed solvent line 62. Therefore, the condensed solvent and a portion of the non-condensable gas in the first recovery tank 80 move to the second recovery tank 85 through the second condensed solvent line 62. The second recovery tank 85 is connected to the condensed solvent discharge line 64 and discharges the condensed solvent through the condensed solvent discharge line 64.

[0068] The vacuum pump 90 is connected to the first recovery tank 80 through the first non-condensable gas recovery line 66, so a portion of the non-condensable gas in the first recovery tank 80 is sucked to the vacuum pump 90 through the first non-condensable gas recovery line 66. In addition, the vacuum pump 90 is connected to the second recovery tank 85 through the second non-condensable gas recovery line 68, so a portion of the non-condensable gas in the second recovery tank 85 is sucked to the vacuum pump 90 through the second non-condensable gas recovery line 68. The vacuum pump 90 is connected to the non-condensable gas discharge line 70 and discharges the sucked non-condensable gas to a post-processing device (not shown) or the like through the non-condensable gas discharge line 70.

[0069] The vacuum pump 90 is connected to the condenser 50 through the first and second non-condensable gas recovery lines 66 and 68 and the first and second condensed solvent lines 60 and 62, and thus the pressure of the condenser 50 can be reduced. In addition, the vacuum pump 90 is connected to the dryer 20 through the evaporation solvent line 38 connecting the dryer 20 and the condenser 50, and can reduce the pressure inside not only the condenser 50 but also the dryer 20. Therefore, the saturation pressure and drying temperature of the solvent in the dryer 20 can be reduced. Therefore, even by the indirect heating type, the raw material in the dryer 20 can be sufficiently dried.

[0070] Figure 3 is a schematic diagram of a vacuum condensation dryer according to another exemplary embodiment of the present disclosure. Figure 4 It is schematically shown Figure 3 View of the preheater.

[0071] like Figure 3 As shown in , the vacuum condensation dryer 10 according to another exemplary embodiment of the present disclosure includes a raw material preheater 200, a raw material feeder 300, a dryer 20, a condenser 50, a vacuum pump 90, and a dry material discharger 700. It should be noted that the vacuum condensation dryer 10 according to another exemplary embodiment of the present disclosure may also include a heat pump similar to the vacuum condensation dryer 10 according to the exemplary embodiment of the present disclosure, but for the convenience of description, in Figure 3It should be understood that the configuration of the heat pump in another exemplary embodiment of the present disclosure and the connection relationship between the heat pump, the dryer 20 and the condenser 50 are the same or very similar to the configuration of the heat pump 40 in the exemplary embodiment of the present disclosure and the connection relationship between the heat pump 40, the dryer 20 and the condenser 50.

[0072] The raw material preheater 200 is configured to be continuously supplied with a raw material containing a solvent (eg, moisture, etc.), to preheat the supplied raw material containing a solvent, and to continuously discharge the preheated raw material containing a solvent. Figure 4 As shown in , the raw material preheater 200 includes a preheating shell 240. The upper portion of the preheating shell 240 is open, thereby forming a raw material hopper 220 that is continuously supplied with a raw material containing a solvent. In addition, a raw material outlet 260 is formed at the lower portion of the preheating shell 26, and the raw material outlet 260 continuously discharges the preheated raw material containing a solvent. The preheating shell 240 itself is configured to increase the temperature of the raw material (containing a solvent) in the preheating shell 240 by transferring heat to the raw material. In one example, a jacket is formed in the preheating shell 240, so that a hot heat transfer fluid can transfer heat to the raw material containing a solvent in the preheating shell 240 while flowing through the jacket. In another example, the preheating shell 240 is equipped with an electric heater, so that heat can be transferred to the raw material containing a solvent in the preheating shell 240. However, the heat transfer device of the raw material preheater 200 is not limited to the example, and includes any device that can transfer heat to the raw material containing a solvent in the preheating shell 240.

[0073] The raw material preheater 200 is configured to increase the partial pressure of the solvent in the atmospheric gas flowing into the dryer 20 together with the raw material by preheating the raw material containing the solvent to a set temperature. When the partial pressure of the solvent in the atmospheric gas increases, the partial pressure of the non-condensable gas in the atmospheric gas decreases, and thus the flow rate of the non-condensable gas in the atmospheric gas flowing into the dryer 20 decreases.

[0074] Table 1

[0075]

[0076]

[0077] Table 1 is a table showing the partial pressure of water vapor in atmospheric gas according to temperature in a saturated state. In this case, water vapor is a typical example of a solvent, and air is a typical example of a non-condensable gas. When the temperature of the atmospheric gas is 60°C, the partial pressure of water vapor in the atmospheric gas is 0.20 bar, and the partial pressure of air is 0.81 bar, so it can be observed that the partial pressure of air is significantly higher than the partial pressure of water vapor. Differently, when the temperature of the atmospheric gas is 90°C, the partial pressure of water vapor in the atmospheric gas is 0.70 bar, and the partial pressure of air is 0.31 bar, so it can be observed that the partial pressure of water vapor is significantly higher than the partial pressure of air. As described above, when the temperature of the atmospheric gas increases, the partial pressure of water vapor increases, but the partial pressure of air decreases, so the amount of air in the atmospheric gas decreases. Therefore, when the raw material preheater 200 preheats the raw material containing the solvent (e.g., moisture, etc.) to the set temperature, the partial pressure of the evaporated solvent in the atmospheric gas around the raw material increases, and the partial pressure of the non-condensable gas decreases, thereby increasing the flow rate of the evaporated solvent in the atmospheric gas flowing into the dryer 20 together with the raw material, and reducing the flow rate of the non-condensable gas. The suction rate of the vacuum pump 90 for maintaining the vacuum degree inside the vacuum condensation dryer 10 is determined by the flow rate of the non-condensable gas that the vacuum pump 90 needs to discharge. However, the evaporated solvent flowing into the dryer 20 is condensed in the condenser 50 and / or the vacuum pump 90 together with the solvent evaporated in the dryer 20, so the influence on the suction rate of the vacuum pump 90 can be ignored. Therefore, it is not necessary to increase the capacity of the vacuum pump 90 in order to maintain the vacuum degree inside the vacuum condensation dryer 10, and the energy consumed by the vacuum pump 90 can be reduced.

[0078] Meanwhile, the cross-sectional area of ​​the raw material hopper 220 through which the raw material is supplied is sufficiently larger than the cross-sectional area of ​​the raw material outlet 260 through which the preheated raw material is discharged, so the raw material supplied into the preheating housing 240 can stay in the preheating housing 240 for a sufficiently long time. Therefore, the raw material supplied into the raw material preheater 200 can receive a sufficient amount of heat from the preheating housing 240. In this case, the cross-sectional area of ​​the raw material outlet 260 can be set by a person of ordinary skill in the art according to the diameter of the raw material, the amount of heat transferred to the raw material by the preheating housing 240 per hour, the set temperature, etc.

[0079] The raw material feeder 300 is disposed between the raw material preheater 200 and the dryer 20 and is configured to supply the raw material containing the solvent preheated by the raw material preheater 200 into the upper portion of one side of the dryer 20. The raw material feeder 300 may be a rotary valve, a drum feeder, etc., but is not limited thereto. The raw material feeder 300 continuously discharges the preheated raw material containing the solvent to the raw material feed line 420, and the raw material feed line 420 is connected to the inlet 22 of the dryer 20, so that the preheated raw material containing the solvent is supplied to the dryer 20 through the raw material inlet 22.

[0080] The dryer 20 is configured to continuously receive the raw material containing solvent preheated by the raw material preheater 200 through the raw material feeder 300, dry the raw material containing solvent by heat exchange with the heat transfer fluid, continuously discharge the dried raw material, and discharge the evaporated solvent evaporated in the process of drying the raw material. The dryer 20 includes a dryer housing 21, in which a drying space is formed. A raw material inlet 22 connected to the raw material feed line 420 is formed at an upper portion of one side portion of the dryer housing 21, so that the preheated raw material containing solvent is supplied to the drying space in the dryer housing 21 through the raw material inlet 22. A raw material outlet 24 is formed at a lower portion of the other side portion of the dryer housing 21, and the raw material outlet 24 is connected to the raw material discharge line 440. Therefore, the dried raw material is continuously discharged from the dryer housing 21 through the raw material discharge line 440.

[0081] In addition, a heat transfer fluid inlet (30, see Figure 1 ), and the heat transfer fluid inlet 30 is connected to the heat transfer fluid supply line (34, see Figure 1 and Figure 2 ). Therefore, the heat transfer fluid supplied with heat energy through heat exchange with the heat exchange medium in the heat pump can be supplied to the dryer 20 through the heat transfer fluid supply line 34 and the heat transfer fluid inlet 30. A heat transfer fluid outlet (32, see Figure 1 ), and the heat transfer fluid outlet 32 ​​is connected to the heat transfer fluid recovery line (36, see Figure 1 and Figure 2 ). Therefore, the heat transfer fluid that performs heat exchange with the raw material, especially the solvent contained in the raw material, flows out of the dryer shell 21 through the heat transfer fluid outlet 32 ​​and the heat transfer fluid recovery line 36, so the heat transfer fluid can be recovered to the heat pump. A jacket or the like is formed in the dryer shell 21, so the heat transfer fluid that flows into the dryer shell 21 through the heat transfer fluid inlet 30 moves through the jacket and does not directly contact the raw material in the dryer shell 21.

[0082] A conveying device (e.g., Figure 1 The conveying device may be a screw 26 having a screw thread 28 formed on an outer circumferential surface, a paddle shaft having a plurality of paddles, etc., which stirs the raw material and transfers the raw material from one side portion to the other side portion. The conveying device stirs the raw material to ensure that heat is uniformly transferred to the raw material. For example, the conveying device may be a screw 26 having a thread 28 formed on an outer circumferential surface, a paddle shaft having a plurality of paddles, etc., but is not limited thereto. The conveying device may be any device that performs the function of stirring the raw material and transferring the raw material from one side portion to the other side portion.

[0083] An evaporation solvent outlet 39 connected to the evaporation solvent line 38 is formed at an upper portion of the other side portion of the dryer housing 21 , and the evaporation solvent evaporated by heat exchange with the heat transfer fluid in the dryer housing 21 flows out to the evaporation solvent line 38 through the evaporation solvent outlet 39 .

[0084] The dry material discharger 700 is disposed on the raw material discharge line 440 and is configured to continuously discharge the raw material dried in the dryer 20. The dry material discharger 700 may be a rotary valve, a drum feeder, etc., but is not limited thereto.

[0085] The condenser 50 is configured to continuously receive the evaporated solvent from the dryer 20, condense the evaporated solvent by heat exchange with the refrigerant, and discharge the condensed condensed solvent and non-condensable gas. The condenser 50 includes a condenser shell 51, in which a condensation space is formed. An evaporated solvent inlet 56 connected to the evaporated solvent line 38 is formed at an upper portion of one side portion of the condenser shell 51, so that the evaporated solvent evaporated in the dryer 20 flows into the condensation space in the condenser shell 51 through the evaporated solvent line 38 and the evaporated solvent inlet 56 together with the evaporated solvent flowing into the dryer 20. A condensed solvent outlet 58 is formed at a lower portion of the condenser shell 51, so that the condensed solvent condensed by heat exchange with the refrigerant in the condenser shell 51 flows out of the condenser shell 51 through the condensed solvent outlet 58. In addition, a refrigerant supply line (54, see Figure 1 ), so the cold refrigerant used to condense the solvent flows into the condenser shell 51 through the refrigerant supply line 54. The other side of the condenser shell 51 is connected to a refrigerant recovery line (52, see Figure 1 ), so the refrigerant that recovers heat energy through heat exchange with the evaporated solvent flows out of the condenser shell 51 through the refrigerant recovery line 52. A jacket or the like is formed in the condenser shell 51, so the refrigerant that flows into the condenser shell 51 through the refrigerant supply line 54 moves through the jacket and does not directly contact the solvent in the condenser shell 51.

[0086] A first condensed solvent pipeline 60 is connected to the other side of the condenser shell 51 , so the condensed solvent condensed in the condenser shell 51 and the non-condensable gas not condensed in the condenser shell 51 are discharged from the condenser shell 51 through the first condensed solvent pipeline 60 .

[0087] The heat pump is configured to recover heat energy from the refrigerant and supply the recovered heat energy to the heat transfer fluid by circulating the heat exchange medium. Figure 1 and Figure 2 As shown in FIG. 1 , the heat pump 40 includes a heat exchange medium circulation pipeline 42, a first heat exchanger 43 and a second heat exchanger 45, an expansion valve 44 and a compressor 46. The heat pump is similar to Figure 1 and Figure 2 The heat pump 40 shown in FIG. 1 is the same as or very similar to the heat pump 40 shown in FIG. 1 and will not be described in detail.

[0088] The vacuum condensation dryer 10 according to another exemplary embodiment of the present disclosure may further include a heat transfer fluid tank (100, see Figure 1 ) and a refrigerant tank (110, see Figure 1 ). The positions and functions of the heat transfer fluid tank 100 and the refrigerant tank 110 are similar to Figure 1 The positions and functions of the heat transfer fluid tank 100 and the refrigerant tank 110 shown in FIG. 1 are the same or very similar, and therefore will not be described in detail.

[0089] The vacuum condensation dryer 10 according to another exemplary embodiment of the present disclosure may further include a vacuum pump 90 and recovery tanks 80 and 85. The connection relationship and function of the vacuum pump 90 and the recovery tanks 80 and 85 according to another exemplary embodiment of the present disclosure are the same or very similar to the connection relationship and function of the vacuum pump 90 and the recovery tanks 80 and 85 according to the exemplary embodiment of the present disclosure, and therefore will not be described in detail.

[0090] While the present disclosure has been described in conjunction with what are presently considered to be practical exemplary embodiments, it is to be understood that the present disclosure is not limited to the disclosed exemplary embodiments. Instead, the present disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A vacuum condensation dryer, comprising: a dryer configured to dry and discharge the raw material containing the solvent through heat exchange between the raw material and a heat transfer fluid, and to discharge the evaporated solvent evaporated during the drying process; a condenser configured to receive the evaporated solvent from the dryer through an evaporated solvent line, condense the evaporated solvent into a condensed solvent by heat exchange with a refrigerant, and discharge the condensed refrigerant; a heat pump configured to recover heat energy from the refrigerant by circulating a heat exchange medium, through heat exchange between the heat exchange medium and the refrigerant, and to supply the recovered heat energy to the heat transfer fluid through heat exchange with the heat exchange medium; a vacuum pump connected to the condenser and configured to reduce the pressure inside the condenser and discharge non-condensable gas generated during the condensation of the solvent; a heat transfer fluid supply line configured to supply a heat transfer fluid supplied with thermal energy from the heat pump to the dryer; a heat transfer fluid recovery line configured to recover the heat transfer fluid having exchanged heat with the raw material from the dryer to the heat pump; a refrigerant supply line configured to supply the refrigerant having exchanged heat with the heat exchange medium from the heat pump to the condenser; a refrigerant recovery line configured to recover the refrigerant having recovered heat energy from the evaporated solvent from the condenser to the heat pump; as well as A heat transfer fluid tank is disposed on the heat transfer fluid supply line or the heat transfer fluid recovery line, the heat transfer fluid tank includes a heat transfer fluid heater for heating the heat transfer fluid and is configured to supply the heated heat transfer fluid to the heat transfer fluid supply line or the heat transfer fluid recovery line.

2. The vacuum condensation dryer according to claim 1, wherein: The heat transfer fluid heater is disposed on the heat transfer fluid supply line to supply heated heat transfer fluid to the dryer through the heat transfer fluid supply line.

3. The vacuum condensation dryer according to claim 1, further comprising A refrigerant tank is provided on the refrigerant supply line or the refrigerant recovery line, the refrigerant tank includes a refrigerant cooler that cools the refrigerant and is configured to supply the cooled refrigerant to the refrigerant supply line or the refrigerant recovery line.

4. The vacuum condensation dryer according to claim 3, wherein: The refrigerant cooler is disposed on the refrigerant supply line to supply cooled refrigerant to the condenser through the refrigerant supply line.

5. The vacuum condensation dryer according to claim 3, wherein: The heat transfer fluid heater or the refrigerant cooler is controlled to operate when the vacuum condensation dryer is stopped.

6. The vacuum condensation dryer according to claim 3, wherein: The heat transfer fluid heater operates so that the temperature of the heat transfer fluid becomes a set heat transfer fluid temperature or higher, or the refrigerant cooler operates so that the temperature of the refrigerant becomes a set refrigerant temperature or lower.

7. The vacuum condensation dryer according to claim 1, wherein: The heat pump comprises: a heat exchange medium circulation pipeline, through which the heat exchange medium circulates; a first heat exchanger disposed on the heat exchange medium circulation line and configured to supply heat energy to the heat transfer fluid through heat exchange between the heat transfer fluid and the heat exchange medium; an expansion valve, the expansion valve being disposed on the heat exchange medium circulation pipeline and expanding the heat exchange medium that has exchanged heat with the heat transfer fluid; a second heat exchanger disposed on the heat exchange medium circulation line and configured to recover heat energy of the refrigerant through heat exchange between the refrigerant and the heat exchange medium; and A compressor is provided on the heat exchange medium circulation line and compresses the heat exchange medium having exchanged heat with the refrigerant.

8. The vacuum condensation dryer according to claim 1, further comprising A recovery tank connected to the condenser through a condensed solvent pipeline and receiving the condensed solvent of the condenser, in, The vacuum pump is connected to the recovery tank through a non-condensable gas recovery line to discharge the non-condensable gas in the condenser and the recovery tank.

9. The vacuum condensation dryer according to claim 1, further comprising a raw material preheater configured to continuously receive and preheat the raw material containing the solvent, and to continuously discharge the preheated raw material containing the solvent, in, The dryer continuously receives and dries the preheated raw material containing solvent from the raw material preheater.

10. The vacuum condensation dryer according to claim 9, wherein: The raw material preheater includes a preheating housing, and The preheat housing is configured to transfer heat to the raw material containing the solvent therein.

11. The vacuum condensation dryer according to claim 1, wherein: The dryer comprises: Dryer housing; a raw material inlet formed at an upper portion of a side portion of the dryer housing; a raw material outlet formed at a lower portion of the other side portion of the dryer housing; and a screw rotatably disposed in the dryer housing, and The raw material containing the solvent is supplied into the dryer shell through the raw material inlet, the raw material containing the solvent is dried while being moved to the other side portion of the dryer shell by the rotating screw, and the dried raw material is discharged from the dryer shell through the raw material outlet.

12. The vacuum condensation dryer according to claim 11, wherein: The dryer also includes: a heat transfer fluid inlet formed at one side of the dryer housing; and a heat transfer fluid outlet formed on the other side of the dryer housing, and The heat transfer fluid flowing into the dryer through the heat transfer fluid inlet exchanges heat with the raw material containing the solvent while moving to the other side, and flows out of the dryer through the heat transfer fluid outlet.

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