WO2016152399A1

WO2016152399A1 - Absorption refrigerator and dehumidifier

Info

Publication number: WO2016152399A1
Application number: PCT/JP2016/056142
Authority: WO
Inventors: 秋澤　淳; 大野　弘幸
Original assignee: 国立大学法人東京農工大学
Priority date: 2015-03-20
Filing date: 2016-02-29
Publication date: 2016-09-29
Also published as: JP6655063B2; JPWO2016152399A1

Abstract

In a regenerator of an absorption refrigerator, a mixture of water and an ionic liquid is heated to transform the water to steam, thereby separating the water and the ionic liquid. A problem encountered in the prior art is that, as compared with sensible heat heating, such latent heat heating requires a temperature at or above the boiling point of the absorption solution, as well as a large amount of heat, and energy efficiency was therefore poor. The absorption refrigerator (10) is provided with: a mixer (30) for mixing a refrigerant and an ionic liquid in which the miscibility with the refrigerant changes with the temperature; a regenerator (40) for heating the mixture of the refrigerant and the ionic liquid mixed by the mixer, and separating the ionic liquid and the refrigerant through the difference in specific gravity thereof while the ionic liquid and the refrigerant remain in the liquid state; and an evaporator (20) for vaporizing the refrigerant separated by the regenerator, to generate cold energy.

Description

Absorption refrigerator and dehumidifier

The present invention relates to an absorption refrigerator and a dehumidifier.

There is known an absorption refrigerator that cools water using an absorption cycle that includes water as a refrigerant and at least one ionic liquid as an absorbent. (For example, refer to Patent Document 1).
Patent Document 1 Special Table 2009-520073

In the regenerator in the absorption refrigerator, the ionic liquid and water are separated by heating a mixture of water and ionic liquid to turn the water into water vapor. Compared with sensible heat heating, such latent heat heating requires a temperature higher than the boiling point of the absorbing solution and a large amount of heat, so that there is a problem that energy efficiency is poor.

The absorption refrigerator in the first aspect of the present invention includes a mixer that mixes an ionic liquid whose compatibility with the refrigerant changes with temperature and the refrigerant, the refrigerant mixed in the mixer, and the ionic liquid. The mixture is heated so that the ionic liquid and the refrigerant are separated from each other by the specific gravity difference between the ionic liquid and the refrigerant, and the refrigerant separated by the regenerator is vaporized to reduce the cold energy. An absorption refrigerator comprising an evaporator to be generated.

The dehumidifier according to the second aspect of the present invention absorbs water contained in the air by allowing the ionic liquid whose compatibility with water changes with temperature to absorb the water, and absorbs the water. And a regenerator that heats the ionic liquid and separates the ionic liquid and the water in a liquid state by a difference in specific gravity between the ionic liquid and the water.

Note that the above summary of the invention does not enumerate all the features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

1 is a schematic diagram illustrating an example of an absorption refrigerator 10. The mixing state and separation state of an ionic liquid and water are shown. It is the table | surface which showed the kind of ionic liquid, and transition temperature Tc. The specific example of the cation of an ionic liquid is shown. The specific example of the anion of an ionic liquid is shown. 4 is a schematic diagram illustrating an example of a separator 44. FIG. It is a schematic diagram which shows the absorption refrigerator 150. FIG. 3 is a schematic diagram showing a first state of a separator 200. FIG. 6 is a schematic diagram showing a second state of the separator 200. FIG. The mixed state and phase-separated state of other ionic liquids with specific gravity smaller than water and water are shown. It is the table | surface which showed the kind and transition temperature Tc of the other ionic liquid whose specific gravity is smaller than water. Specific examples of cations of other ionic liquids are shown. The specific example of the anion of another ionic liquid is shown. 3 is a schematic diagram showing a separator 300. FIG. It is a schematic diagram which shows an example of the dehumidifier 400. FIG. It is a schematic diagram which shows the absorption refrigerator 500. It is a schematic diagram which shows the absorption refrigerator 550.

Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

FIG. 1 is a schematic diagram showing an example of an absorption refrigerator 10. The absorption refrigerator 10 includes an evaporator 20, an absorber 30 as an example of a mixer, a regenerator 40, and a cooler 50. In the absorption refrigerator 10, first, the refrigerant is vaporized in the evaporator 20 to generate cold heat. The vaporized refrigerant is absorbed by the absorbent by the absorber 30. The refrigerant that has absorbed the refrigerant is separated from the refrigerant and the absorbent in the regenerator 40. The absorbent from which the refrigerant has been separated is cooled by the cooler 50 and then transported to the absorber 30 to absorb the vaporized refrigerant again. The refrigerant separated from the absorbent is also cooled by the cooler 50 and then conveyed to the evaporator 20. Again, the refrigerant is vaporized in the evaporator 20 to generate cold.

Thus, the absorption refrigerator 10 continuously generates cold by repeating the above cycle. In the present embodiment, water is used as the refrigerant used in the absorption refrigerator 10. Moreover, an ionic liquid is used as an absorbent. Here, the ionic liquid is a salt in a liquid state at a temperature of 100 ° C. or lower, and in the present embodiment, an ionic liquid whose compatibility with water as a refrigerant changes depending on the temperature is used. In the following description, the ionic liquid may be referred to as IL.

FIG. 2 shows a mixed state and separated state of IL and water. Assuming that the temperature at which the compatibility of IL and water changes is the transition temperature Tc, as shown in FIG. 2, the state of the mixed solution 100 in which IL and water are compatible at a temperature lower than the transition temperature Tc. It becomes. When the mixed liquid 100 is heated to raise the temperature to the transition temperature Tc or higher, the compatibility between IL and water decreases, and the liquid is separated into a lower layer composed of the IL layer 104 and an upper layer composed of the aqueous layer 102 while remaining in a liquid state. It will be in the state. Note that the separation between the IL layer 104 and the water layer 102 may not be complete separation, and the IL layer 104 may contain a slight amount of water, or the water layer 102 may contain a slight amount of IL.

FIG. 3 is a table showing the types of IL and the transition temperature Tc. As shown in FIG. 3, the transition temperatures Tc of these ILs are all lower than the boiling point of water.

FIG. 4 shows a specific example of the cation of IL, and FIG. 5 shows a specific example of the anion of IL. Thus, IL can adjust the transition temperature Tc at which the compatibility with water changes as shown in FIG. 3 by recombining the cation shown in FIG. 4 and the anion shown in FIG. In this embodiment, [P ₄₄₄₄ ] [TsO] having a transition temperature Tc of 50 ° C. is used as IL.

Referring to FIG. 1 again, the evaporator 20 generates cold by vaporizing water. The evaporator 20 includes a vaporization unit 22 that vaporizes water and a collection unit 24 that collects IL contained in the water. The evaporator 20 is connected to the regenerator 40 via the expansion valve 60, whereby the evaporator 20 is adjusted to a predetermined internal pressure that is lower than the internal pressure of the regenerator 40.

Due to the internal pressure difference between the regenerator 40 and the evaporator 20, water as a refrigerant is conveyed from the regenerator 40 to the evaporator 20 through the expansion valve 60. In the evaporator 20, water is ejected toward the vaporization unit 22. The ejected water takes the heat from the vaporizing section 22 and vaporizes. Further, the vaporizing unit 22 cools the object 80 by taking heat away from the object 80 passing through the vaporizing unit 22. In this way, the evaporator 20 outputs the cooled object 80. Note that the object 80 may be air, water, antifreeze (brine), or the like.

The input temperature of the object 80 is detected by the thermometer 26, and the output temperature is detected by the thermometer 28. Based on the detected temperature, the amount of water supplied to the evaporator 20 is controlled. For example, when the object 80 is cooled and the input temperature of the object 80 is higher than a preset temperature, the amount of water supplied to the evaporator 20 is increased. On the other hand, when the input temperature of the object 80 is lower than a preset temperature, the amount of water supplied to the evaporator 20 is reduced. Note that the amount of water supplied to the evaporator 20 may be similarly controlled by the output temperature.

The recovery unit 24 recovers the water containing IL transported to the evaporator 20. When the water containing IL is collected, the collecting unit 24 sends the water containing a predetermined amount of IL to the absorber 30 to create an equilibrium state. Thus, by providing the recovery unit 24 in the evaporator 20, it is possible to prevent IL from staying in the evaporator 20. Thereby, the absorption refrigerator 10 can be operated without adding IL in the middle of operation of the absorption refrigerator 10. Note that the recovery unit 24 may transport the recovered water containing IL to the absorber 30 using a liquid pump.

The absorber 30 absorbs vaporized water in IL. The absorber 30 is provided connected to the evaporator 20. Since the evaporator 20 and the absorber 30 are connected, the internal pressures of the evaporator 20 and the absorber 30 are substantially equal. By cooling the IL that has absorbed water with the cooling water 82, the internal pressure of the absorber 30 is lowered. Due to the decrease in the internal pressure, an internal pressure difference is generated between the evaporator 20 and the absorber 30. Due to this internal pressure difference, the vaporized water is transported from the evaporator 20 to the absorber 30.

The absorber 30 is connected to the regenerator 40 via an expansion valve 62. Since the internal pressure of the absorber 30 is lower than the internal pressure of the regenerator 40, IL as an absorbent is conveyed from the regenerator 40 to the absorber 30 through the expansion valve 62.

When the absorber 30 absorbs the water vaporized by the IL, the temperature of the IL rises due to the absorption heat of the water. The absorber 30 cools IL using the cooling water 82. Thereby, IL is cooled and water absorption is promoted. The IL that has absorbed water in this way is transported to the regenerator 40 by the liquid pump 70.

The regenerator 40 includes a heater 42 and a separator 44. The heater 42 heats the IL that has absorbed the water using the external fluid 84, and separates the IL and the water by the specific gravity difference between the IL and the water while being in a liquid state. IL [P ₄₄₄₄ ] [TsO] used in the present embodiment has a transition temperature Tc of 50 ° C. Since the heater 42 only needs to be able to heat to a temperature higher than 50 ° C., which is the transition temperature Tc, in the present embodiment, for example, a heat source having a temperature higher than 50 ° C. and 60 ° C. or lower is used. Heating. Note that by using IL with a low transition temperature Tc, the heater 42 can use a lower temperature heat source. As a result, the absorption refrigerator 10 can output the cold using the low-temperature exhaust heat that has been discarded because it has not been used so far.

FIG. 6 is a schematic diagram showing an example of the separator 44. The separator 44 takes out IL and water separated by the heater 42 separately. The separator 44 includes a container 110, a sensor 112, one supply valve 114, and two

discharge valves

116 and 118.

The container 110 is a hollow container and stores a mixed liquid separated into IL and water. The supply pipe 120 connected to the heater 42 is connected to the upper surface of the container 110 via the supply valve 114. The discharge pipe 122 is connected to a predetermined height on the side surface of the container 110 via the discharge valve 116. The discharge pipe 124 is connected to the lower surface of the container 110 via a discharge valve 118. The predetermined height of the side surface of the container 110 is, for example, a height that is 6/10 with respect to the height of the container 110 when the interface between IL and water is located at the center of the container 110. That's it. By connecting the discharge valve 116 to a height that is 6/10 with respect to the height of the container 110, even after the discharge valve 116 is released and water is taken out, the height of the container 110 is reduced to 1 /. Ten heights of water are left in the container 110.

In the absorption refrigerator 10, if IL is contained in the coolant water, the amount of water containing the IL transported from the recovery unit 24 to the absorber 30 increases. By providing the discharge valve 116 at a position higher than the interface between water and IL and leaving the water in the container 110 even after the water is taken out, the amount of IL conveyed to the evaporator 20 can be reduced. it can. Thereby, the quantity of the water containing IL conveyed from the collection | recovery part 24 to the absorber 30 can be reduced.

When the supply valve 114 is opened while the container 110 is empty, the mixed liquid separated into IL and water is supplied from the upper surface of the container 110. The mixed liquid of IL and water is supplied until the sensor 112 detects the liquid level. When the sensor 112 detects the liquid level, the sensor 112 closes the supply valve 114 and stops the supply of the mixed liquid of IL and water.

After a predetermined time has elapsed since the supply valve 114 was closed, the discharge valve 116 is opened, and the upper layer water is taken out. The predetermined time is, for example, 5 minutes. The predetermined time may be a time required for separation of the liquid mixture of IL and water measured in advance, and may be a time obtained by multiplying the time by a predetermined safety factor. . The extracted water is cooled by the cooler 50 and conveyed to the evaporator 20.

For example, the discharge valve 116 is closed after a predetermined time has elapsed. The predetermined time may be a time required for the water in the container 110 measured in advance to be discharged through the discharge valve 116, and a predetermined safety factor is set for the time. The multiplied time may be used. Thereafter, the discharge valve 118 is opened, and IL and water are taken out. The extracted IL and water are cooled by the cooler 50 and conveyed to the absorber 30.

The cooler 50 cools the IL and water taken out by the separator 44. The cooler 50 cools IL and water passing through the cooler 50 by circulating the coolant 86. The water cooled by the cooler 50 is supplied to the evaporator 20 through the expansion valve 60. And the evaporator 20 vaporizes the supplied water again and generates cold. On the other hand, the IL cooled by the cooler 50 is supplied to the absorber 30 through the expansion valve 62. Then, the absorber 30 again absorbs the vaporized water using the supplied IL. As described above, the absorption refrigerator 10 in the present embodiment continuously generates cold by repeatedly executing the processing described above in the evaporator 20, the absorber 30, the regenerator 40, and the cooler 50.

The absorption refrigerator 10 of the present embodiment uses IL whose compatibility with water as a refrigerant changes at 50 ° C. as an absorbent. Therefore, IL and water can be separated by the difference in specific gravity between IL and water only by sensible heat heating the mixture of IL and water to 50 ° C. or higher. Thus, in the absorption refrigerator 10 of this embodiment, since the latent heat heating which vaporizes a refrigerant | coolant is not performed in order to isolate | separate a refrigerant | coolant and an absorbent, the energy efficiency of the absorption refrigerator 10 can be improved greatly.

The COP (coefficient of performance) of the absorption refrigerator 10 in the present embodiment will be described. In the absorption refrigerator 10, the transition temperature Tc of IL as an absorbent is 55 ° C., heated from 35 ° C. to 60 ° C. in the

heater

42, and 1 from a mixture of IL and water containing 60% by weight of water. The COP was calculated as / 10 water was separated, and the COP was 1.5. Considering that the COP of the conventional absorption refrigerator that performs latent heat heating at 90 ° C. to separate water and the absorbent is 0.7, the energy efficiency of the absorption refrigerator 10 in this embodiment is the conventional efficiency. Great improvement over absorption refrigerators.

Further, in the present embodiment, an example has been described in which the drain valve 116 is opened and upper water is taken out after a predetermined time has elapsed since the supply valve 114 was closed. However, the present invention is not limited to this. For example, a light emitting element and a light receiving element are provided at a height of 6/10 with respect to the container 110, and it is detected whether IL and water are separated based on the amount of light received by the light receiving element. Also good. The transparency of the water layer 102 is higher than the transparency in a state where IL and water are compatible. Therefore, a threshold may be provided for the amount of light received by the light receiving element, and the discharge valve 116 may be released on condition that the amount of light received by the light receiving element exceeds the threshold.

Further, in the present embodiment, the heater 42 has shown an example in which the IL that has absorbed water is heated using the external fluid 84 to separate the IL from the water. The fluid 84 may be used to heat the container 110 of the separator 44. By heating the container 110, the separation state of IL and water in the container 110 can be maintained, so that the separation ability of IL and water in the separator 44 is improved.

Next, another example of the absorption refrigerator 10 will be described. FIG. 7 is a schematic diagram showing the absorption refrigerator 150. In FIG. 7, the same reference numerals are assigned to elements common to those in FIG. The absorption refrigerator 150 illustrated in FIG. 7 further includes a heat exchanger 152.

The heat exchanger 152 performs heat exchange between the IL containing water transported from the absorber 30, which is an example of a mixer, and the IL transported from the separator 44. The temperature of the IL containing water conveyed from the absorber 30 is lower than the temperature of the IL conveyed from the separator 44. The heat exchanger 152 recovers the heat of the IL conveyed from the separator 44 having a relatively high temperature, and heats the IL containing water conveyed from the absorber 30. Thereby, the heating in the heater 42 can be reduced.

Next, another example of the separator 44 will be described. FIG. 8 is a schematic diagram showing a first state of the separator 200. In FIG. 8, the same elements as those in FIG. In the following drawings, the black valve indicates a closed valve, and the white valve indicates an open valve. Separator 200 includes a plurality of separators 44 connected in parallel. Then, the liquid mixture of IL and water is supplied in turn while switching the plurality of separators 44, and after a predetermined time has passed since the supply, the IL and water are separated. Are taken out separately.

The separator 200 includes four

containers

202, 204, 206, 208, four

supply valves

210, 212, 214, 216, four sensors 112, and eight

discharge valves

220, 222, 224, 226, 230, 232, 234, 236, one supply pipe 240, and two

discharge pipes

242, 244. The supply pipe 240 connected to the heater 42 is branched into four for the purpose of connecting to the four

containers

202, 204, 206, 208. One of the branched supply pipes 240 is connected to the upper surface of the container 202 via a supply valve 210. Similarly, one of the other branched supply pipes is connected to the top surface of the container 204 via a supply valve 212. One of the other branched supply pipes is connected to the top surface of the container 206 via a supply valve 214, and one of the other branched supply pipes is connected to the container 208 via a supply valve 216. Connected to the top of the.

The discharge pipe 242 is branched into four for the purpose of connecting to the four

containers

202, 204, 206, 208. One of the branched discharge pipes 242 is connected to a predetermined height on the side surface of the container 202 via a discharge valve 220. Similarly, one of the other branched discharge pipes 242 is connected to a predetermined height on the side of the container 204 via a discharge valve 222. One of the other branched discharge pipes 242 is connected to a predetermined height on the side of the container 206 via a discharge valve 224, and one of the other branched discharge pipes 242 is It is connected to a predetermined height on the side surface of the container 208 via a discharge valve 226. In addition, since the predetermined height is the same as the predetermined height in the separator 44, a duplicate description is omitted.

The discharge pipe 244 is branched into four for the purpose of connecting to the four

containers

202, 204, 206, 208. One of the branched discharge pipes 244 is connected to the lower surface of the container 202 via a discharge valve 230. Similarly, one of the other branched discharge pipes 242 is connected to the lower surface of the container 204 via a discharge valve 232. One of the other branched discharge pipes 242 is connected to a predetermined height on the side of the container 206 via a discharge valve 234, and one of the other branched supply pipes is connected to the discharge pipe 242. It is connected to the lower surface of the container 208 via a valve 236.

In the first state, in the container 202, the discharge valve 220 is opened, and water is taken out from the container 202. Further, in the container 204, the discharge valve 232 is opened, and IL and a small amount of water are taken out from the container 204. In the container 206, the supply valve 214 is opened, and the mixed liquid separated into IL and water is supplied to the container 206. Further, the container 208 is left in a state where it is filled with the mixed liquid separated into water and IL, and the IL and water are separated.

FIG. 9 is a schematic diagram showing a second state of the separator 200. In FIG. 9, the same elements as those in FIG. In the second state, in the container 202, the discharge valve 220 is closed and the discharge valve 230 is opened, so that IL and a small amount of water are taken out from the container 202. In the container 204, the discharge valve 232 is closed and the supply valve 212 is opened, and the mixed liquid separated into IL and water is supplied to the container 204. In the container 206, the container 206 is left in a state filled with the mixed liquid separated into IL and water, and the IL and water are separated. In the container 208, the discharge valve 226 is opened, and water is taken out from the container 208.

Thus, in the separator 200, a step in which a mixed solution separated into IL and water is supplied, a step in which the mixture is left separated in a state filled with a mixed solution of IL and water, a step in which water is taken out, The process of removing the IL and some amount of water is performed in turn in each of the four

containers

202, 204, 206, 208. And the process shifted | deviated 1 in each container is performed in the same time so that each process may be performed simultaneously with four containers 202,204,206,208. Thereby, the mixed liquid separated into IL and water can be continuously supplied from the heater 42 to the separator 200. Further, water can be continuously supplied from the separator 200 to the evaporator 20, and IL can be continuously supplied from the separator 200 to the absorber 30.

8 and 9 show an example of the separator 200 in which the number of containers is four, but the number of containers is not limited to four and may be plural. Moreover, you may determine the number of containers based on the time of four processes mentioned above.

FIG. 10 shows a mixed state and phase separation state of other IL and water having a specific gravity smaller than that of water. The IL shown in FIG. 10 is in the state of a mixed solution 100 in which IL and water are compatible at a temperature lower than the transition temperature Tc. When the mixed liquid 100 is heated and the temperature is raised to the transition temperature Tc or higher, the compatibility between IL and water decreases, and the upper layer composed of the IL layer 104 and the lower layer composed of the aqueous layer 102 are separated. Become. Thus, in the IL having a specific gravity smaller than that of water, the IL layer 104 is the upper layer and the water layer 102 is the lower layer, unlike the example shown in FIG.

FIG. 11 is a table showing other IL types having a specific gravity smaller than that of water and the transition temperature Tc. FIG. 12 shows specific examples of other IL cations, and FIG. 13 shows specific examples of other IL anions. Thus, IL contains the cation shown in FIG. 12 and the anion shown in FIG. 13, and the specific gravity of the IL is smaller than that of water as a refrigerant. For example, [P ₆₆₆₈ ] [EtOHPO ₂ ] can be used as such an IL.

FIG. 14 is a schematic diagram showing the separator 300. In FIG. 14, elements common to those in FIG. The separator 300 corresponds to IL having a specific gravity smaller than that of water as a refrigerant as an absorbent.

The separator 300 includes four

containers

302, 304, 306, 308, four

supply valves

210, 212, 214, 216, four sensors 112, four sensors 310, and eight

discharge valves

220, 222, 224, 226, 230, 232, 234, 236, one supply pipe 240, and two

discharge pipes

244, 320.

The discharge pipe 320 is branched into four for the purpose of connecting to the four

containers

302, 304, 306, 308. One of the branched discharge pipes 320 is connected to the lower surface of the container 302 via a discharge valve 220. Similarly, one of the other branched discharge pipes 320 is connected to the lower surface of the container 304 via a discharge valve 222. Further, one of the other branched discharge pipes 320 is connected to the lower surface of the container 306 via the discharge valve 224, and one of the other branched discharge pipes 320 is connected to the container via the discharge valve 226. It is connected to the lower surface of 308.

In the state shown in FIG. 14, in the container 302, the discharge valve 220 is opened, and water is taken out from the container 302. The water is taken out until the sensor 310 detects the liquid level. When the sensor 310 detects the liquid level, the sensor 310 closes the discharge valve 220 and stops taking out water. The height of the sensor 310 is set such that, for example, water having a height of 1/10 of the height of the container 302 remains at the bottom of the container after the water extraction is stopped.

In the container 304, the discharge valve 232 is opened, and IL and a small amount of water are taken out from the container 304. In the container 306, the supply valve 214 is opened, and the mixed liquid separated into IL and water is supplied to the container 306. Further, the container 308 is left in a state filled with the mixed liquid separated into IL and water to separate IL and water.

Thus, water can be taken out from the lower surface of the container 302 by using IL having a specific gravity smaller than that of water. In the container 302, the pressure applied to the discharge pipe 320 is based on the weight obtained by adding the weight of water and the weight of IL. For this reason, the pressure applied to the discharge pipe 320 is greater than the pressure in the separator 200 when IL having a specific gravity greater than that of water is used. By increasing the pressure, the water extraction speed from the discharge pipe 320 can be increased.

FIG. 15 is a schematic diagram showing an example of the dehumidifier 400. In FIG. 15, elements that are the same as those in FIG. The dehumidifier 400 includes an absorber 410, a regenerator 40, and a cooler 50.

In the dehumidifier 400, first, the water 414 contained in the air 412 is absorbed by the IL by the absorber 410, and the dehumidified air 412 is output. The absorber 410 is common to the absorber 30 shown in FIG. 1 in the configuration in which the water 414 is absorbed by the IL, but includes the water 414 by taking in the air 412 including the water 414 and causing the IL to absorb the water 414. It differs in that no air 412 is output.

The IL that has absorbed the water 414 is separated into water 414 and IL in the regenerator 40. The IL from which the water 414 has been separated is cooled by the cooler 50 and then transferred to the absorber 30 to absorb the water 414 from the air 412 again. The regenerator 40 discharges the water 414 separated from the IL. As described above, the dehumidifier 400 continuously outputs the air 412 that does not contain the water 414 by repeating the above cycle. In the dehumidifier 400 shown in FIG. 15, [P ₄₄₄₄ ] [TsO] having a transition temperature Tc of 50 ° C. was used as IL.

Also in the dehumidifier 400 shown in FIG. 15, IL whose compatibility with water 414 changes at 50 ° C. is used as the refrigerant absorbent. Therefore, the IL and the water 414 can be separated by the specific gravity difference between the IL and the water 414 only by sensible heating the mixture of the IL and the water 414 to 50 ° C. or higher. For this reason, also in the dehumidifier 400 shown in FIG. 15, since the latent heat is not used to separate the IL and the water 414, the energy efficiency of the dehumidifier 400 can be greatly improved.

In the present embodiment, for example, an IL using [P ₄₄₄₄ ] [TsO] is used as the refrigerant absorbent. However, the refrigerant absorbent may include a plurality of types of IL. Moreover, additives other than IL may be included in IL, for example, a surfactant may be included in IL. Further, the refrigerant absorbent may be other than IL, and examples of such embodiments are shown in FIGS.

FIG. 16 is a schematic diagram showing an absorption refrigerator 500. In FIG. 16, elements that are the same as those in FIG. The mixer 520 of the absorption refrigerator 500 shown in FIG. 16 further includes a separation unit 510 in addition to the absorber 30 and the liquid pump 70. In this embodiment, it is a lithium bromide aqueous solution that absorbs water vaporized by the absorber 30. As another example of the refrigerant absorbent, an aqueous solution of a substance having high deliquescence such as calcium bromide or calcium chloride may be used.

The aqueous lithium bromide solution that has absorbed water in the absorber 30 is conveyed to the separation unit 510 by the liquid pump 70. The separation unit 510 includes a semipermeable membrane 516, a first chamber 512 and a second chamber 514 separated by the semipermeable membrane 516. The aqueous lithium bromide solution is stored in the second chamber 514. Water contained in the lithium bromide aqueous solution permeates the semipermeable membrane and moves to the first chamber 512 that houses the IL. The permeation method of the semipermeable membrane may be reverse osmosis or forward osmosis. The IL that has absorbed the water in this way is sent to the regenerator 40.

The IL separated from the water in the regenerator 40 is transferred to the first chamber 512 of the separation unit 510 by the liquid pump 72 after being cooled by the cooler 50. The water containing IL recovered by the recovery unit 24 of the evaporator 20 is also sent to the first chamber 512 of the separation unit 510. In this way, IL is used again to absorb water passing through the semipermeable membrane. On the other hand, the aqueous lithium bromide solution in the second chamber is returned to the absorber 30 and used again for absorbing the vaporized water. Thereby, water can be efficiently absorbed by using a lithium bromide aqueous solution having high compatibility with water as a refrigerant absorbent. Moreover, IL and water can be efficiently separated based on the change in compatibility.

Next, another example of the absorption refrigerator 500 will be described. FIG. 17 is a schematic diagram showing an absorption refrigerator 550. In FIG. 17, elements that are the same as those in FIG. The absorption refrigerator 550 shown in FIG. 17 further includes a concentration controller 560. As the concentration controller 560, for example, a capacitive deionization (CDI) apparatus that performs electrochemical deionization processing may be used.

The lithium bromide aqueous solution sent from the separation unit 510 to the concentration controller 560 is divided into an aqueous solution containing lithium bromide at a high concentration and an aqueous solution containing a low concentration. The low-concentration lithium bromide aqueous solution is mixed with the lithium bromide aqueous solution conveyed from the absorber 30 to the separation unit 510. On the other hand, the high concentration lithium bromide aqueous solution is sent to the absorber 30. Thereby, the density | concentration of the lithium bromide aqueous solution which flows into the absorber after the water separation by a semipermeable membrane can be raised further.

Moreover, in this embodiment, the absorption refrigerator 10 provided with the evaporator 20, the absorber 30 which is an example of a mixer, the regenerator 40, and the cooler 50 each was shown. However, it is not restricted to the said structure, The evaporator 20, the absorber 30, the regenerator 40, and the cooler 50 may each be provided with two or more. Similarly, in the dehumidifier 400, a plurality of absorbers 410, regenerators 40, and coolers 50 may be provided.

As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

10, 150, 500, 550 Absorption refrigerator, 20 evaporator, 22 vaporizer, 24 recovery unit, 26, 28 thermometer, 30, 410 absorber, 40 regenerator, 42 heater, 44, 200, 300 separator , 50 cooler, 60, 62 expansion valve, 70, 72 liquid pump, 80 object, 84 external fluid, 82, 86 cooling water, 100 liquid mixture, 102 water layer, 104 IL layer, 110, 202, 204, 206 , 208, 302, 304, 306, 308 Container, 112, 310 Sensor, 114, 210, 212, 214, 216 Supply valve, 116, 118, 220, 222, 224, 226, 230, 232, 234, 236 Discharge valve , 120, 240 supply pipe, 122, 124, 242, 244, 320 discharge pipe, 152 heat Exchanger, 400 dehumidifier, 412 air, 414 water, 510 separation unit, 512 first chamber 514 second chamber, 516 a semi-permeable membrane, 520 a mixer, 560 concentration adjuster

Claims

A mixer for mixing the refrigerant with an ionic liquid whose compatibility with the refrigerant changes with temperature;
A regenerator that heats a mixture of the refrigerant and the ionic liquid mixed in the mixer and separates the ionic liquid and the refrigerant in a liquid state by a specific gravity difference between the ionic liquid and the refrigerant;
An evaporator that generates cold by vaporizing the refrigerant separated by the regenerator;
Absorption refrigerator equipped with.
The absorption refrigerator according to claim 1, wherein the mixer has an absorber that causes the ionic liquid to absorb the refrigerant vaporized by the evaporator.
The mixer is
An absorber for absorbing the refrigerant vaporized in the evaporator by a refrigerant absorbent different from the ionic liquid;
The absorption refrigerator according to claim 1, further comprising: a separation unit that is transported from the absorber and separates from the refrigerant absorbent that has absorbed the refrigerant.
The absorption refrigerator according to claim 3, wherein the separation unit separates the refrigerant from the refrigerant absorbent using osmotic pressure.
The absorption refrigerator according to claim 3 or 4, wherein the refrigerant absorbent contains lithium bromide, calcium bromide, or calcium chloride.
The evaporator includes a vaporization unit that vaporizes the refrigerant, a collection unit that collects the ionic liquid contained in the refrigerant,
With
The absorption refrigerator according to any one of claims 1 to 5, wherein the recovery unit recovers an ionic liquid contained in the refrigerant and conveys the recovered ionic liquid to the mixer.
The regenerator includes a heater and a separator,
The heater heats the ionic liquid that has absorbed the refrigerant and separates the ionic liquid from the liquid while the refrigerant remains in a liquid state.
The absorption refrigerator according to any one of claims 1 to 6, wherein the separator takes out the separated refrigerant and the ionic liquid separately.
The regenerator includes a plurality of the separators in parallel, and the heater supplies the refrigerant and the ionic liquid in order while switching the plurality of separators, and the separated refrigerant and the ionic liquid are supplied. The absorption refrigerator according to claim 7, wherein the refrigerant and the ionic liquid are taken out separately after a predetermined time has elapsed since the start.
The absorption refrigerator according to claim 7 or 8, wherein the separator takes out the refrigerant and the ionic liquid separately while leaving the refrigerant in the separator.
The absorption refrigerator according to claim 9, wherein the separator takes out the ionic liquid after taking out the refrigerant while leaving the refrigerant in the separator.
The regenerator further comprises a cooler,
The absorption cooler according to any one of claims 7 to 10, wherein the cooler cools the ionic liquid taken out by the separator.
The refrigerant is water;
The temperature at which the compatibility of the ionic liquid and the water changes when the ionic liquid and the water are mixed in an equal amount is within a range of 5 ° C to 70 ° C. The absorption refrigerator according to any one of claims 11 to 11.
The absorption refrigerator according to claim 12, wherein the heater is heated using a heat source of 60 ° C or lower, and a temperature at which the compatibility between the ionic liquid and the water changes is equal to or lower than the temperature of the heat source.
An absorber that absorbs the water contained in the air into an ionic liquid whose compatibility with water changes with temperature and outputs dehumidified air; and
A regenerator that heats the ionic liquid that has absorbed the water and separates the ionic liquid and the water in a liquid state by a specific gravity difference between the ionic liquid and the water;
A dehumidifier.