Hydrophobic hollow fiber membrane-based absorber in vapor absorption refrigeration system

Abstract

The present invention relates to an absorber for an absorption chiller, and more specifically, to an absorber for an absorption chiller using a hydrophobic hollow fiber membrane that effectively absorbs water vapor into an aqueous LiBr solution, effectively removes the heat of absorption generated during absorption, and enables the miniaturization and lightweighting of the absorber, and to an absorption chiller using the same. An absorber for an absorption chiller using a hydrophobic hollow fiber membrane according to the present invention comprises: a column-shaped housing having one end and the other end, the interior of which is formed of a hydrophobic hollow fiber membrane layer; a first channel mounted in the longitudinal direction of the housing within the housing, through which a high-concentration LiBr aqueous solution is supplied and moved from a regenerator of the absorption chiller; a cooling channel mounted in the longitudinal direction of the housing within the housing, through which cooling water is supplied and moved; and a second channel formed in the longitudinal direction of the housing within the housing, through which water vapor is supplied and moved from an evaporator of the absorption chiller. A through hole is formed around the first channel within the housing, and the high-concentration LiBr aqueous solution discharged from the first channel through the through hole into the hollow fiber membrane layer moves through the hollow fiber membrane layer and absorbs the water vapor supplied through the second channel to convert it to a low concentration, and the heat of absorption generated upon absorption of the water vapor is cooled by the cooling channel.

Description

Technology Field

[0001] The present invention relates to an absorber for an absorption chiller, and more specifically, to an absorber for an absorption chiller using a hydrophobic hollow fiber membrane that effectively absorbs water vapor into an aqueous LiBr solution, effectively removes the heat of absorption generated during absorption, and enables the miniaturization and lightweighting of the absorber, and to an absorption chiller using the same. Background Technology

[0002] An absorption chiller is a type of device that generates chilled water using the heat of vaporization of a refrigerant.

[0003] Such absorption chillers utilize waste heat or heat sources rather than electrical energy to produce a refrigeration effect, and generally vaporize the refrigerant within an evaporator that is close to a vacuum. When the refrigerant vaporizes, it is configured to generate cold water by exchanging heat with the heat transfer tubes inside the evaporator.

[0004] Water (H2O) is typically used as the refrigerant, and an aqueous solution of lithium bromide (LiBr) can be used as an absorbent to recover the refrigerant.

[0005] In particular, since such absorption chillers use water as a refrigerant, they are more environmentally friendly than compression chillers, and they also have the advantage of enabling efficient energy utilization by reusing waste gases as a heat source.

[0006] Typically, an absorption chiller may consist of a regenerator, a condenser, an evaporator, and an absorber, and is structured such that the refrigerant and absorbent liquid circulate through these components.

[0007] More specifically, in the evaporator, the liquid refrigerant vaporizes and undergoes a phase change into refrigerant vapor, and in this process, chilled water is generated through the heat of vaporization of the refrigerant.

[0008] The refrigerant vapor generated in the evaporator moves to the absorber and mixes with the absorbent solution (concentrated solution).

[0009] The diluted absorbent solution (dilute solution) mixed with refrigerant vapor is transferred to a regenerator, where it is heated by a driving heat source to separate the refrigerant vapor.

[0010] The separated refrigerant vapor moves to the condenser, where it is cooled and converted back into liquid refrigerant.

[0011] The liquid refrigerant is supplied back to the evaporator to repeat the aforementioned process.

[0012] Meanwhile, the absorber of a conventional absorption chiller applies a falling film structure to efficiently cool the heat of absorption generated when water vapor is absorbed into a high-concentration LiBr aqueous solution supplied from a regenerator.

[0013] However, in the thicker parts of the film structure where cooling is not effectively applied, water vapor is not well absorbed into the LiBr aqueous solution, and there is a problem in that absorption does not occur well due to changes in the shape of the film caused by tilting or vibration when the absorption refrigerator is applied to combustion devices, etc. Prior art literature

[0014] Registered Patent 10-1763796 Registered Utility Model 20-0285190 The problem to be solved

[0015] The present invention aims to solve the aforementioned problems by providing an absorber for an absorption refrigerator using a hydrophobic hollow fiber membrane that effectively absorbs water vapor into an aqueous LiBr solution, effectively removes the heat of absorption generated during absorption, and enables miniaturization and weight reduction, as well as an absorption refrigerator using the same. means of solving the problem

[0016] To achieve the above objective, an absorber for an absorption chiller using a hydrophobic hollow fiber membrane according to the present invention comprises: a column-shaped housing having one end and the other end, the interior of which is formed of a hydrophobic hollow fiber membrane layer; a first channel mounted in the longitudinal direction of the housing within the housing, through which a high-concentration LiBr aqueous solution is supplied and moved from a regenerator of the absorption chiller; and a cooling channel mounted in the longitudinal direction of the housing within the housing, through which cooling water is supplied and moved. The apparatus comprises a second channel formed lengthwise in the hollow fiber membrane layer within the housing and through which water vapor is supplied from the evaporator of the absorption chiller and moves, wherein a through hole is formed around the first channel within the housing, and a high-concentration LiBr aqueous solution discharged from the first channel through the through hole into the hollow fiber membrane layer moves through the hollow fiber membrane layer and absorbs water vapor supplied through the second channel to be converted to a low concentration, and the heat of absorption generated upon absorption of water vapor is cooled by the cooling channel.

[0017] The first channel is positioned at the center of the housing, the cooling channel is arranged radially around the first channel, and the second channel is arranged radially around the first channel at the outer edge of the cooling channel.

[0018] The above housing further comprises a plurality of baffles mounted internally to partially block the movement of the LiBr aqueous solution, wherein the LiBr aqueous solution discharged from the through hole to the hollow fiber membrane layer has its movement path extended by the baffles, thereby increasing the heat exchange efficiency with the cooling channel.

[0019] The above baffle comprises a first baffle and a second baffle spaced apart from each other within the housing, wherein a first movement groove for the movement of a LiBr aqueous solution is formed in the first baffle and a second movement groove for the movement of a LiBr aqueous solution is formed in the second baffle, and the first movement groove and the second movement groove are arranged at different angles when viewed from the longitudinal direction of the housing.

[0020] The above through hole comprises a first through hole through which a LiBr aqueous solution is discharged to the outside from the first channel, and a second through hole through which a LiBr aqueous solution from outside the first channel flows into the interior of the first channel, wherein the first through hole is formed adjacent to one end of the first channel through which the LiBr aqueous solution is supplied into the interior of the housing, and the second through hole is formed adjacent to the other end of the first channel through which the LiBr aqueous solution is discharged to the outside of the housing, and communication between the first through hole and the second through hole through the interior of the first channel is blocked.

[0022] In addition, to achieve the above objective, the absorption chiller of the present invention comprises a regenerator, a condenser, an evaporator, an absorber, and a heat exchanger, wherein the absorber is characterized by being composed of the absorber described above. Effects of the invention

[0023] According to the absorber for an absorption chiller using the hydrophobic hollow fiber membrane of the present invention as described above, and the absorption chiller using the same, the following effects are achieved.

[0024] Water vapor is well absorbed into the LiBr aqueous solution, and the heat of absorption generated during absorption can be effectively removed.

[0025] In addition, by controlling the flow of the LiBr aqueous solution within the absorption chiller, heat and mass transfer efficiency can be increased, enabling the construction of a compact and lightweight system. Brief explanation of the drawing

[0026] FIG. 1 is an overall configuration diagram of an absorber of an absorption chiller according to an embodiment of the present invention. FIG. 2 is a cross-sectional structural diagram of an absorber according to an embodiment of the present invention. Specific details for implementing the invention

[0027] The absorption chiller of the present invention comprises a regenerator, a condenser, an evaporator, an absorber, a heat exchanger, etc.

[0028] Since the above-mentioned regenerator, condenser, evaporator, heat exchanger, etc., are identical to the conventional configuration, a detailed description thereof is omitted.

[0029] As shown in FIGS. 1 and 2, the absorber of the present invention comprises a housing (10), a first channel (20), a cooling channel (30), a second channel (40), etc.

[0030] The above housing (10) is formed in the shape of a long column having one end and the other end.

[0031] A hydrophobic hollow fiber membrane layer (11) is inserted inside the above housing (10).

[0032] The first channel (20) is mounted inside the housing (10) along the longitudinal direction of the housing (10).

[0033] A high-concentration LiBr aqueous solution supplied from the regenerator of the absorption refrigerator is supplied into and moves through the first channel (20) mentioned above.

[0034] The first channel (20) may be mounted as a single tube along the longitudinal direction of the housing (10), or it may be divided into two and mounted at one end and the other end of the housing (10), respectively.

[0035] Through holes (11, 12) are formed around the first channel (20) inside the housing (10).

[0036] The above through holes (11, 12) are passages for the LiBr aqueous solution to move to the first channel (20) and the hollow fiber membrane layer (11).

[0037] The above cooling channel (30) is mounted lengthwise in the direction of the housing (10) inside the housing (10), and cooling water is supplied and moves inside.

[0038] The second channel (40) is formed lengthwise in the hollow fiber membrane layer (11) within the housing (10) in the longitudinal direction of the housing (10), and water vapor is supplied from the evaporator of the absorption chiller and moves through it.

[0039] The first channel (20) is positioned in the center of the housing (10) while penetrating the hollow fiber membrane layer (11).

[0040] A plurality of the above cooling channels (30) penetrate the above hollow fiber membrane layer (11) and are arranged radially around the first channel (20).

[0041] The second channel (40) is formed directly in the hollow fiber membrane layer (11) and is arranged radially around the first channel (20) at the outer edge of the cooling channel (30).

[0042] The high-concentration LiBr aqueous solution discharged from the first channel (20) to the hollow fiber membrane layer (11) through the through hole moves through the hollow fiber membrane layer (11) and absorbs water vapor supplied through the second channel (40) to be converted to a low concentration, and the heat absorbed when water vapor is absorbed is cooled by the cooling channel (30).

[0043] The through hole formed in the first channel (20) for the above LiBr aqueous solution to move is composed of a first through hole (21) and a second through hole (22).

[0044] The first through hole (21) is a passage through which the LiBr aqueous solution inside the first channel (20) is discharged to the outside of the first channel (20), i.e., to the hollow fiber membrane layer (11).

[0045] The second through hole (22) is a passage through which the LiBr aqueous solution of the hollow fiber membrane layer (11) flows into the interior of the first channel (20), that is, outside the first channel (20).

[0046] The first through hole (21) is formed adjacent to one end of the first channel (20) through which the LiBr aqueous solution is supplied into the interior of the housing (10).

[0047] The second through hole (22) is formed adjacent to the other end of the first channel (20) through which the LiBr aqueous solution is discharged to the outside of the housing (10).

[0048] Communication between the first through hole (21) and the second through hole (22) through the interior of the first channel (20) is blocked.

[0049] Therefore, the LiBr aqueous solution introduced into one end of the first channel (20) can only be discharged through the first through hole (21), and cannot be discharged through the second through hole (22).

[0050] And, the LiBr solution that flows into the second through hole (22) cannot be discharged back into the first through hole (21).

[0051] As shown in FIG. 2, the first channel (20) is formed long, with the first through hole (21) formed at one end and the second through hole (22) formed at the other end, and the middle part may be blocked.

[0052] Alternatively, the first channel (20) may be divided into two, with the first through hole (21) formed in one and the second through hole (22) formed in the other.

[0053] The present invention may further include a plurality of baffles mounted inside the housing (10) to partially block the movement of the LiBr aqueous solution.

[0054] The LiBr aqueous solution discharged from the first through hole (21) to the hollow fiber membrane layer (11) has its shortest travel path extended by the baffle, thereby increasing the heat exchange efficiency with the cooling channel (30).

[0055] The above baffles are formed by including a first baffle (51) and a second baffle (52) spaced apart from each other within the housing (10).

[0056] A first moving groove (51a) for moving the LiBr aqueous solution is formed in the first baffle (51), and a second moving groove (52a) for moving the LiBr aqueous solution is formed in the second baffle (52).

[0057] The first moving groove (51a) and the second moving groove (52a) are arranged at different angles when viewed from the longitudinal direction of the housing (10).

[0058] Due to this structure, the LiBr aqueous solution moved to the hollow fiber membrane layer (11) through the first through hole (21) must move through the first moving groove (51a) and the second moving groove (52a) as its shortest path is changed by the first baffle (51) and the second baffle (52), and thus comes into contact with the cooling channel (30) in between, thereby being cooled more effectively.

[0060] The operation process of the present invention, composed of the configuration described above, will be examined below.

[0061] A LiBr aqueous solution concentrated to a high degree in the regenerator of an absorption refrigerator is introduced into one end of the first channel (20) as shown in FIG. 2.

[0062] The LiBr aqueous solution introduced into one end of the first channel (20) is discharged to the outside of the first channel (20) through the first through hole (21) and moves through the hollow fiber membrane layer (11).

[0063] At this time, since the cooling channel (30) is arranged around the first channel (20), the LiBr aqueous solution moves toward the outer surface of the housing (10) while being cooled, and when the moved LiBr aqueous solution reaches the second channel (40), it absorbs the water vapor supplied to the second channel (40).

[0064] At this time, the heat absorbed by the LiBr aqueous solution as it absorbs steam is removed by the cooling water moving in the cooling channel (30).

[0065] The LiBr aqueous solution in which water vapor has been absorbed passes through the first moving groove (51a) of the first baffle (51) and the moving groove of the second baffle (52), thereby changing its movement path to be longer, and in the process, additional water vapor is absorbed and simultaneously cooled better by the cooling channel (30).

[0066] Through this process, the LiBr aqueous solution moved to the other end of the housing (10) is converted from a high-concentration LiBr aqueous solution into a low-concentration LiBr aqueous solution diluted, and moves into the interior of the first channel (20) through the second through hole (22).

[0067] As described above, the present invention allows water vapor to be effectively absorbed into an aqueous LiBr solution using a hydrophobic hollow fiber membrane layer (11), effectively removes the heat of absorption generated during absorption through a cooling channel (30) and a baffle, and reduces the overall volume of the absorber.

[0068] The present invention can enable the development of a high-efficiency, compact absorption chiller through the application of a hollow fiber membrane type isothermal absorber, as well as a regenerator of the same structure and heat and material recovery.

[0070] The absorber for an absorption chiller using a hydrophobic hollow fiber membrane according to the present invention and the absorption chiller using the same are not limited to the aforementioned embodiments and can be implemented with various modifications within the scope permissible by the technical concept of the present invention. Explanation of the symbols

[0071] 10 : Housing, 11 : Hollow fiber membrane layer, 20: 1st channel, 21: 1st through hole, 22: 2nd through hole, 30 : Cooling channel, 40 : Channel 2, 51 : 1st baffle, 51a : 1st movable groove, 52 : 2nd baffle, 52a : 2nd movable groove.

Claims

Claim 1 An absorber for an absorption chiller comprises: a column-shaped housing having one end and the other end, the interior of which is formed of a hydrophobic hollow fiber membrane layer; a first channel mounted in the longitudinal direction of the housing within the housing, through which a high-concentration LiBr aqueous solution is supplied and moved from a regenerator of the absorption chiller; a cooling channel mounted in the longitudinal direction of the housing within the housing, through which cooling water is supplied and moved; and a second channel formed in the longitudinal direction of the housing within the housing, through which water vapor is supplied and moved from an evaporator of the absorption chiller. A through hole is formed around the first channel within the housing, and the high-concentration LiBr aqueous solution discharged from the first channel through the through hole into the hollow fiber membrane layer moves through the hollow fiber membrane layer and absorbs the water vapor supplied through the second channel to convert to a low concentration, and the heat of absorption generated upon absorption of the water vapor is cooled by the cooling channel, and the first channel is positioned at the center of the housing. An absorber for an absorption chiller using a hydrophobic hollow fiber membrane, characterized in that cooling channels are arranged radially around the first channel, and second channels are arranged radially around the first channel from the outer edge of the cooling channels. Claim 2 delete Claim 3 An absorber for an absorption chiller using a hydrophobic hollow fiber membrane according to claim 1, further comprising a plurality of baffles mounted inside the housing to partially block the movement of an aqueous LiBr solution, wherein the aqueous LiBr solution discharged from the through hole to the hollow fiber membrane layer has its movement path extended by the baffles, thereby increasing the heat exchange efficiency with the cooling channel. Claim 4 An absorber for an absorption chiller using a hydrophobic hollow fiber membrane according to claim 3, wherein the baffle comprises a first baffle and a second baffle spaced apart from each other within the housing, wherein the first baffle has a first movement groove formed for the movement of a LiBr aqueous solution and the second baffle has a second movement groove formed for the movement of a LiBr aqueous solution, and wherein the first movement groove and the second movement groove are arranged at different angles when viewed from the longitudinal direction of the housing. Claim 5 An absorber for an absorption chiller using a hydrophobic hollow fiber membrane according to claim 1, wherein the through hole comprises a first through hole through which an aqueous LiBr solution is discharged to the outside from the first channel and a second through hole through which an aqueous LiBr solution from outside the first channel is introduced into the interior of the first channel, wherein the first through hole is formed adjacent to one end of the first channel through which the aqueous LiBr solution is supplied into the interior of the housing, and the second through hole is formed adjacent to the other end of the first channel through which the aqueous LiBr solution is discharged to the outside of the housing, and communication between the first through hole and the second through hole through the interior of the first channel is blocked. Claim 6 An absorption chiller comprising a regenerator, a condenser, an evaporator, an absorber, and a heat exchanger, wherein the absorber is characterized in that it is composed of the absorber of any one of claims 1, 3 to 5.

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