JP2015145740A - absorption refrigeration apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that, since a generator is warmed to evaporate a refrigerant absorbed by an absorption solution when starting up an absorption refrigeration apparatus, it may take time to warm the generator, supply of a liquid refrigerant to an evaporator may be delayed and a medium to be refrigerated cannot be sufficiently refrigerated.SOLUTION: The absorption refrigeration apparatus includes: the generator which heats a refrigerant absorbed by the absorption solution to generate refrigerant vapor and an absorption solution of low refrigerator concentration; a condenser which is connected to the generator and condenses the refrigerant vapor to produce the liquid refrigerant; the evaporator which evaporates the liquid refrigerant produced by the condenser to refrigerate an object; a refrigerant transportation pipe connected to the condenser and the evaporator and forming a passage in which the refrigerant flows; an absorber which is connected to the evaporator and makes the absorption solution of the low refrigerant concentration absorb the refrigerant vapor to produce an absorption solution of high refrigerant concentration; a first absorption solution transportation pipe and a second absorption solution transportation pipe connected to the generator and the absorber; and a refrigerant buffer tank provided in the refrigerant transportation pipe for storing the liquid refrigerant.

Description

  The present invention relates to an absorption refrigeration apparatus.

The absorption refrigeration apparatus transports the liquid refrigerant obtained by liquefying the refrigerant vapor evaporated in the generator to the evaporator and evaporates the liquid refrigerant in the evaporator to cool the cooling medium (for example, , See Patent Document 1).
Patent Document 1 JP 2000-337732 A

  When starting up the absorption refrigeration system, the generator is warmed to evaporate the refrigerant absorbed in the absorption solution. For this reason, it took time to warm the generator, the supply of the liquid refrigerant to the evaporator was delayed, and there was a problem that the medium to be cooled could not be sufficiently cooled.

  An absorption refrigeration apparatus according to an aspect of the present invention includes a generator that contains an absorption solution having a high refrigerant concentration, heats the refrigerant absorbed in the absorption solution, and generates refrigerant vapor and an absorption solution having a low refrigerant concentration. A condenser connected to the generator to condense the refrigerant vapor into a liquid refrigerant; an evaporator for evaporating the liquid refrigerant generated in the condenser to cool an object; the condenser; A refrigerant transport pipe connected to the evaporator and forming a path through which the refrigerant flows; and an absorber connected to the evaporator to absorb the refrigerant vapor in the absorbent solution having a low refrigerant concentration to obtain the absorbent solution having a high refrigerant concentration; A first absorbent solution transport pipe connected to the generator and the absorber and having a path through which the absorbent solution having a high refrigerant concentration flows; and an absorbent solution having a low refrigerant concentration connected to the generator and the absorber. The first route that flows And the absorption solution transport pipe, provided in the coolant transport tube, and a refrigerant buffer tank for storing the liquid coolant.

  The 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.

The schematic diagram of the absorption refrigeration apparatus which concerns on this embodiment is shown. The cross-sectional schematic diagram of the buffer tank for refrigerant | coolants is shown. The schematic diagram of the absorption refrigeration apparatus at the time of start-up is shown. (A) It is a cross-sectional schematic diagram which shows the state of the buffer tank for refrigerant | coolants at the time of starting. (B) It is a cross-sectional schematic diagram which shows the state of the buffer tank for refrigerant | coolants at the time of operation | movement. The schematic diagram of an absorption refrigeration apparatus in case cooling of a target object is stopped is shown. (A) It is a cross-sectional schematic diagram which shows the state of the buffer tank for refrigerant | coolants when cooling is stopped. (B) It is a cross-sectional schematic diagram which shows the state of the buffer tank for refrigerant | coolants at the time of stopping an absorption refrigerating apparatus. The partial schematic diagram of the other absorption refrigeration apparatus which concerns on this embodiment is shown. The cross-sectional schematic diagram of the other buffer tank for refrigerant | coolants which concerns on this embodiment is shown.

  Hereinafter, the present invention will be described through embodiments of the invention, but 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 shows a schematic diagram of an absorption refrigeration apparatus 10 according to the present embodiment. In FIG. 1, white valves and valves indicate open valves and valves.

  The absorption refrigeration apparatus 10 includes a supply side device 12 and an output side device 14. In the present embodiment, the supply-side device 12 and the output-side device 14 are provided apart from each other, and the supply-side device 12 and the output-side device 14 include the refrigerant transfer tube 100, the first absorbent solution transfer tube 102, The two absorbent solution transfer pipes 104 are connected.

  As the refrigerant used in the absorption refrigeration apparatus 10, an ammonia liquid can be used. In that case, an aqueous ammonia solution is used as an absorbent. Note that water can also be used as the refrigerant, and in that case, lithium bromide is used as the absorbent. In this embodiment, since it does not crystallize even at low temperatures, an example using an ammonia liquid as a refrigerant and an aqueous ammonia solution as an absorbent is shown. However, the present invention is not limited thereto, and water as a refrigerant and lithium bromide as an absorbent. It may be used.

  The supply side device 12 includes generators 50 and 52, rectifiers 54 and 56, a condenser 60, a heat exchanger 70, a reflux pump 94, and a cooling device 120. The generator 50 is provided connected to the rectifier 54, and the generator 52 is provided connected to the rectifier 56. Since the generator 52 and the rectifier 56 have the same configuration as the generator 50 and the rectifier 54, the description of the generator 52 and the rectifier 56 is substituted with the description of the generator 50 and the rectifier 54. . The generator 52 may be called a regenerator.

  The generator 50 contains a high-concentration aqueous ammonia solution containing a large amount of ammonia. The generator 50 heats the stored high-concentration aqueous ammonia solution using the exhaust heat 116 to generate ammonia gas. Since the difference in boiling point between ammonia and water is small, the ammonia gas generated from the generator 50 contains a large amount of water vapor and becomes a mixed vapor of ammonia and water. The remaining aqueous ammonia solution from which ammonia gas has been generated is an aqueous ammonia solution having a low ammonia concentration.

  The mixed steam of ammonia and water is conveyed to the lower part of the rectifier 54 connected to the generator 50. The rectifier 54 concentrates the mixed vapor of ammonia and water conveyed from the generator 50 into high-purity ammonia gas. The rectifier 54 has, for example, a bubble cap type tray. In the rectifier 54, the trays are installed in multiple stages. In each tray, the high-purity ammonia concentrated solution and the mixed vapor of ammonia and water come into gas-liquid contact, and the water vapor in the mixed vapor is absorbed by the concentrated ammonia solution. And the ammonia in a concentrated solution gasifies with the heat of condensation generated at the time of absorption. By repeating such a process in each tray, the mixed vapor is concentrated to high purity ammonia gas.

  The rectifier 54 returns the remaining low-concentration aqueous ammonia solution obtained by extracting high-purity ammonia gas by rectification to the generator 50. Since the low-concentration aqueous ammonia solution returned to the generator 50 is heated by the generator 50 and the rectifier 54, it is at a high temperature. The low-efficiency ammonia aqueous solution that has reached a high temperature passes through the heat exchanger 70 and is conveyed to the output-side device 14 through the second absorbent solution conveyance tube 104 that forms a path through which the low-concentration ammonia aqueous solution flows. The heat exchanger 70 gives the heat of the low-concentration aqueous ammonia solution transported from the generator 50 to the output-side device 14 to the high-concentration aqueous ammonia solution transported from the output-side device 14 to the generator 50. . And since the warmed high concentration ammonia aqueous solution is heated in the generator 50, the heating amount in the generator 50 can be decreased. By providing the heat exchanger 70 in this way, the utilization efficiency of the exhaust heat 116 in the generator 50 can be improved.

  In this embodiment, although the generator 50 showed the example which heats high concentration ammonia aqueous solution using the exhaust heat 116, heating of high concentration ammonia aqueous solution is not restricted to the case where exhaust heat 116 is used. The generator 50 may include a heating device instead of the exhaust heat 116, and heat the high-concentration aqueous ammonia solution using the heat of the heating device. Further, the high-concentration aqueous ammonia solution may be heated using the exhaust heat 116 and the heat of the heating device in combination.

  Moreover, in this embodiment, the example provided with the rectifiers 54 and 56 was shown. However, when water is used as the refrigerant and lithium bromide is used as the absorbent, the difference between the boiling point of lithium bromide and the boiling point of water is large, so that the rectifiers 54 and 56 need not be provided.

  Further, since the exhaust heat 116 is supplied to the generator 50 and the rectifier 54 and the exhaust heat 118 is supplied to the generator 52 and the rectifier 56, respectively, the generator 50 and the rectifier 54 are supplied with the exhaust heat 116. The generator 52 and the rectifier 56 may be provided in the vicinity of the factory to which the exhaust heat 118 is supplied. As a result, the exhaust heat 116 and 118 can be used effectively, and the heat insulation equipment for the pipes that transport the exhaust heat 116 and 118 can be reduced. Further, the number of combinations of the generator and the rectifier may be determined according to the total amount of exhaust heat required by the absorption refrigeration apparatus 10 and the amount of exhaust heat supplied on the exhaust heat supply side. The term “waste heat” is used in the sense of heat exhausted and used from a factory or the like, but the term “waste heat” may be used in the same meaning.

  The condenser 60 condenses the high-purity ammonia gas by using the cooling water 114 cooled by the cooling device 120 to produce ammonia liquid. The condensed ammonia liquid is transported to the output side device 14 using the refrigerant transport pipe 100. A part of the condensed ammonia liquid is transported to the rectifier 54 using the reflux pump 94 and used for rectification of the ammonia gas.

  The internal pressures of the generators 50 and 52, the rectifiers 54 and 56, and the condenser 60 constituting the supply side device 12 are approximately the same internal pressure. In the present embodiment, the internal pressure is 15 atmospheres. The internal pressures of the generators 50 and 52, the rectifiers 54 and 56, and the condenser 60 are adjusted by the conveyance pressure of the high-concentration aqueous ammonia solution that is conveyed from the output side device 14 to the generators 50 and 52.

  The output-side device 14 includes a refrigerant buffer tank 20, high-pressure evaporators 30 and low-pressure evaporators 32 having different internal pressures, absorbers 40 and 42, a solution pump 92, and a cooling device 120. The refrigerant buffer tank 20 is provided on the output side device 14 side of the refrigerant conveyance pipe 100 and stores an ammonia liquid as a refrigerant. Since the refrigerant buffer tank 20 is connected to the supply-side device 12 through the refrigerant conveyance pipe 100, the internal pressure of the refrigerant buffer tank 20 is the internal pressure of the supply-side apparatus 12 although there is a pressure loss due to the refrigerant conveyance pipe 100. And roughly the same. Therefore, when the internal pressure of the supply side device 12 is 15 atm, the internal pressure of the refrigerant buffer tank 20 is also approximately 15 atm. The refrigerant transport pipe 100 upstream of the refrigerant buffer tank 20 is provided with a valve 80, and the ammonia liquid from the supply-side device 12 to the refrigerant buffer tank 20 is controlled by controlling ON / OFF of the valve 80. Is controlled.

  The high pressure evaporator 30 has a higher internal pressure than the low pressure evaporator 32. In the present embodiment, the internal pressure of the high-pressure evaporator 30 is 4 atmospheres, and the internal pressure of the low-pressure evaporator 32 is 3 atmospheres. An expansion valve 82 is provided at the inlet of the high-pressure evaporator 30, and the pressure in the high-pressure evaporator 30 is maintained by the expansion valve 82. The supply amount of the ammonia liquid to the high-pressure evaporator 30 is controlled by adjusting the opening diameter of the expansion valve 82.

  The expansion valve 82 is opened, and the ammonia liquid is transferred from the 15 atm refrigerant buffer tank 20 to the high pressure evaporator 30 at 4 atm. The ammonia liquid is ejected toward the object 110, takes heat from the object 110, evaporates and gasifies. The input temperature of the object 110 is detected by the thermometer 34, and the output temperature is detected by the thermometer 36. Then, the supply amount of the ammonia liquid is controlled based on the detected input temperature and output temperature.

  In the case where the object 110 is cooled, when the input temperature of the object 110 is higher than a presumed temperature, the supply amount of the ammonia liquid is increased, and the input temperature of the object 110 is lower than the presumed temperature. In some cases, the supply amount of the ammonia liquid is reduced. Similarly, when the object 110 is cooled, the supply amount of the ammonia liquid is increased when the output temperature of the object 110 is higher than the required temperature, and the output temperature of the object 110 is lower than the required temperature. In addition, the supply amount of the ammonia liquid is reduced. The object 110 is transported and used for cooling an air conditioner or a freezer in a living space. As the object 110, air, water, ammonia liquid, or the like may be used.

  The expansion valve 84 is opened, and the ammonia liquid is conveyed from the 15 atm refrigerant buffer tank 20 to the 3 atm low pressure evaporator 32. The ammonia liquid is ejected toward the target object 112, takes heat from the target object 112, and evaporates and gasifies. Since the low-pressure evaporator 32 has a lower internal pressure than the high-pressure evaporator 30, the object 112 is cooled to a lower temperature than the object 110 by adiabatic expansion of the ammonia gas generated by evaporation. Thus, the high pressure evaporator 30 and the low pressure evaporator 32 cool the objects 110 and 112 to different temperatures.

  An expansion valve 84 is provided at the inlet of the low-pressure evaporator 32, and the pressure in the low-pressure evaporator 32 is maintained by the expansion valve 84. The supply amount of the ammonia liquid to the low-pressure evaporator 32 is controlled by adjusting the opening diameter of the expansion valve 84. As the target object 112, air, water, ammonia liquid, or the like is used in the same manner as the target object 110.

  The absorber 40 is provided connected to the high-pressure evaporator 30, and the absorber 42 is provided connected to the low-pressure evaporator 32. Thus, a plurality of absorbers 40 and 42 are provided corresponding to the internal pressures of the high-pressure evaporator 30 and the low-pressure evaporator 32. In the case of having a plurality of evaporators having different internal pressures, by providing a plurality of absorbers corresponding to the internal pressure of the evaporator, ammonia gas generated in the high-pressure evaporator 30 is generated in the absorber 40 and in the low-pressure evaporator 32. The ammonia gas can be conveyed to the absorber 42 without stagnation. When the internal pressures of the high-pressure evaporator 30 and the low-pressure evaporator 32 are the same, an absorber having a large common capacity may be connected to the high-pressure evaporator 30 and the low-pressure evaporator 32.

  The ammonia gas generated in the high pressure evaporator 30 is conveyed to the absorber 40. The absorber 40 absorbs the ammonia gas into the low concentration aqueous ammonia solution conveyed from the generator 50 to obtain a high concentration aqueous ammonia solution. Since the high-pressure evaporator 30 and the absorber 40 are connected to each other, the internal pressures of the high-pressure evaporator 30 and the absorber 40 are the same. However, when ammonia gas is absorbed, the volume of the absorber is reduced. The internal pressure inside decreases. Due to the internal pressure difference generated by the absorption of the ammonia gas, the ammonia gas is conveyed from the high-pressure evaporator 30 to the absorber 40.

  In addition, when a low concentration aqueous ammonia solution absorbs ammonia gas, the temperature rises due to the condensation heat of ammonia. The absorber 40 cools the aqueous ammonia solution having a low concentration using the cooling water 114 cooled by the cooling device 120. Thereby, the low concentration ammonia aqueous solution is cooled, and absorption of ammonia gas is promoted. The solution pump 92 transports the high-concentration ammonia aqueous solution that has absorbed the ammonia gas stored in the absorber 40 to the supply-side device 12 through the first absorbent solution transport pipe 102 that forms a path through which the high-concentration ammonia aqueous solution flows. .

  Ammonia gas generated in the low-pressure evaporator 32 is also transported to the absorber 42 by the same pressure difference. Also in the absorber 42, the ammonia gas generated in the low-pressure evaporator 32 is absorbed by the low-concentration aqueous ammonia solution conveyed from the generator 50 to obtain a high-concentration aqueous ammonia solution. In the absorber 42 as well, the low-concentration aqueous ammonia solution is cooled using the cooling water 114 cooled by the cooling device 120.

  The solution pump 92 is provided in the first absorbent solution transport pipe 102 and transports the high concentration aqueous ammonia solution stored in the absorber 42 to the supply side device 12 through the first absorbent solution transport pipe 102. The high-concentration aqueous ammonia solution sent out from the absorbers 40 and 42 merges at the connecting portion 106 and is conveyed to the generators 50 and 52 of the supply-side device 12. The internal pressures of the generators 50 and 52, the rectifiers 54 and 56, and the condenser 60 are controlled by the conveying pressure of the high-concentration aqueous ammonia solution in the solution pump 92. The low concentration aqueous ammonia solution generated in the generators 50 and 52 is transported to the absorbers 40 and 42 through the second absorbent solution transport pipe 104. The low-concentration aqueous ammonia solution may be conveyed by the pressure difference between the generator 50 and the absorber 40 generated by the solution pump 92 or the pressure difference between the generator 52 and the absorber 42, A separate solution pump may be provided in the second absorbent solution transport pipe 104, and a low concentration aqueous ammonia solution may be transported to the absorbers 40 and 42 using the solution pump.

  In the case where the absorbers 40 and 42 having different internal pressures are provided as in the absorption refrigeration apparatus 10 shown in the present embodiment, the absorbers 40 and 42 of the first absorbent solution transport pipe 102 and the connecting portion 106 are provided. A check valve 88 is provided. Thereby, it is possible to prevent the discharged aqueous ammonia solution from flowing backward from the absorber 40 having an internal pressure higher than that of the absorber 42 to the absorber 42 having an internal pressure lower than that of the absorber 40. Further, pressure reducing valves 86 are provided at the end portions of the second absorbent solution transport pipe 104 on the absorbers 40 and 42 side, respectively. Thereby, the internal pressure of the absorber 40 and the absorber 42 is maintained. A branch pipe connected to the second absorbent solution transport pipe 104 may be provided on the output side device 14 side and downstream of the solution pump 92. The branch pipe is provided with a flow rate adjusting valve, and according to the output of the object 110 in the high-pressure evaporator 30 and the output of the object 112 in the low-pressure evaporator 32, the first absorbent solution transport pipe is provided. The amount of the high-concentration aqueous ammonia solution flowing to 102 may be controlled.

  In the present embodiment, the output side device 14 is provided on the output side of the cooled object and in an urban area where the output is used. Thereby, while being able to use effectively the cooled target object outputted, the heat insulation equipment of the conveyance pipe which conveys a target object can be decreased.

  Moreover, in this embodiment, although the output side apparatus 14 showed the example containing two combinations of an evaporator and an absorber, it is not restricted to this. The output side device 14 may include three or more combinations of evaporators and absorbers according to the output temperature of the object, or may be one. Furthermore, when the output side device 14 includes a plurality of combinations of evaporators and absorbers, a plurality of combinations of evaporators and absorbers having the same internal pressure may be included.

  FIG. 2 is a schematic sectional view of the refrigerant buffer tank 20. In FIG. 2, the branching portion 109 to the refrigerant transport pipe having the expansion valve 84 is omitted for simplification of the drawing. The refrigerant buffer tank 20 includes a buffer container 24 that stores ammonia liquid, and a liquid level sensor 26 that detects the liquid level of the ammonia liquid in the buffer container 24.

  The ammonia liquid is stored in the refrigerant buffer tank 20 by opening the valve 80 with the expansion valve 82 closed. The ammonia liquid stored in the refrigerant buffer tank 20 is used by opening the expansion valve 82.

  FIG. 3 is a schematic diagram of the absorption refrigeration apparatus 10 at the time of start-up. In FIG. 3, the same elements as those in FIG. In FIG. 3, black valves and valves indicate closed valves and valves. As shown in FIG. 3, the valve 80 is closed when the absorption refrigeration apparatus 10 is started up. Therefore, the ammonia liquid stored in the refrigerant buffer tank 20 is used as the ammonia liquid used in the high-pressure evaporator 30 and the low-pressure evaporator 32. Thereby, even when the absorption refrigeration apparatus 10 is started up, the ammonia liquid is sufficiently supplied to the high-pressure evaporator 30 and the low-pressure evaporator 32, and the objects 110 and 112 can be sufficiently cooled. Then, the ammonia liquid stored in the refrigerant buffer tank 20 is diffused into the absorption refrigeration apparatus 10.

  FIG. 4A is a schematic cross-sectional view showing the state of the refrigerant buffer tank 20 at startup, and FIG. 4B is a schematic cross-sectional view showing the state of the refrigerant buffer tank 20 during operation. . At the time of start-up, as shown in FIG. 4A, the refrigerant buffer tank 20 stores an ammonia liquid as a refrigerant. The liquid level of the ammonia liquid is a predetermined position detected by the liquid level sensor 26. Note that the predetermined position is the amount of ammonia liquid used when the output side device 14 is operated at the maximum output during the time required for the startup preparation of the supply side device 12 and the time required for the startup preparation. It is good also as a position which can ensure the volume corresponding to the quantity of ammonia liquid multiplied by the safety factor.

  At startup, the ammonia liquid stored in the refrigerant buffer tank 20 is conveyed to the high-pressure evaporator 30 and the low-pressure evaporator 32. On the other hand, the valve 80 is closed until the preparation for starting up the supply side device 12 is completed. When the valve 80 is closed, the ammonia liquid condensed by the condenser 60 may be returned to the rectifiers 54 and 56 by the reflux pump 94. The preparation for starting up the supply side device 12 is, for example, that the generators 50 and 52, 54 and 56 are heated to generate ammonia gas, and the ammonia gas is condensed in the condenser 60 to become an ammonia liquid. This refers to a process until a predetermined amount of ammonia liquid is stored in the condenser 60.

  During operation, as shown in FIG. 4B, the valve 80 is opened, and the ammonia liquid is supplied from the supply side device 12 to the refrigerant buffer tank 20. For example, the valve 80 is automatically opened according to a predetermined time profile by a control unit provided in the absorption refrigeration apparatus 10. The valve 80 may be opened on the condition that the amount of ammonia liquid condensed in the condenser 60 is measured and exceeds a predetermined threshold, or may be opened manually by an operator.

  The ammonia liquid is supplied from the supply-side device 12 to the refrigerant buffer tank 20 by a pressure difference caused by a decrease in the pressure in the refrigerant buffer tank 20 due to the discharge of the ammonia liquid stored in the refrigerant buffer tank 20. Be transported. Even if the temperature in the condenser 60 of the supply side device 12 is made higher than the temperature in the refrigerant buffer tank 20, a pressure difference is caused between the condenser 60 and the refrigerant buffer tank due to the temperature difference. Good. Then, the ammonia liquid may be supplied from the supply side device 12 to the refrigerant buffer tank 20 by the generated pressure difference. Alternatively, a separate solution pump may be provided in the refrigerant transfer pipe 100 on the supply side device 12 side, and the ammonia liquid may be transferred to the refrigerant buffer tank 20 using the solution pump.

  The ammonia liquid is temporarily stored in the refrigerant buffer tank 20 and then supplied from the expansion valve 82 to the high-pressure evaporator 30. The supply rate of the ammonia liquid from the supply side device 12 may be such that an amount of the ammonia liquid corresponding to the usage rate of the ammonia liquid when the output side device 14 is operated at the maximum output may be supplied. The schematic diagram of the absorption refrigeration apparatus 10 during operation is the same as that in FIG. 1, and the valve 80, the expansion valve 82, and the expansion valve 84 are opened.

  FIG. 5 is a schematic diagram of the absorption refrigeration apparatus when the cooling of the objects 110 and 112 is stopped. After the cooling of the objects 110 and 112 is stopped, the expansion valve 82 and the expansion valve 84 are closed while the valve 80 is open. In this state, the solution pump 92 is driven, and a predetermined amount of ammonia liquid is stored in the refrigerant buffer tank 20.

  FIG. 6A is a schematic cross-sectional view showing the state of the refrigerant buffer tank 20 when the cooling of the objects 110 and 112 is stopped, and FIG. 6B is the case when the absorption refrigeration apparatus 10 is stopped. 3 is a schematic cross-sectional view showing a state of the refrigerant buffer tank 20. FIG. When the cooling of the objects 110 and 112 is stopped, the solution pump 92 is driven with the valve 80 opened and the expansion valve 82 closed as shown in FIG. As a result, the ammonia liquid diffused into the absorption refrigeration apparatus 10 is again stored in the refrigerant buffer tank 20, and the liquid level of the ammonia liquid in the refrigerant buffer tank 20 rises.

  As shown in FIG. 6B, when the liquid level of the ammonia liquid in the refrigerant buffer tank 20 reaches a position in contact with the liquid level sensor 26, the valve 80 is closed and the solution pump 92 is stopped. Then, after the solution pump 92 is stopped, the absorption refrigeration apparatus 10 is stopped. In this manner, in the absorption refrigeration apparatus 10, before the absorption refrigeration apparatus 10 stops, a predetermined amount of ammonia liquid is stored in the refrigerant buffer tank 20. As a result, even when the ammonia liquid is not supplied for a certain time at startup, the ammonia liquid can be supplied to the high-pressure evaporator 30 and the low-pressure evaporator 32 without delaying the supply of the ammonia liquid.

  As described above, the absorption refrigeration apparatus 10 according to the present embodiment includes the refrigerant buffer tank 20 that stores the ammonia liquid used in the high-pressure evaporator 30 and the low-pressure evaporator 32 when the absorption refrigeration apparatus 10 is started up. . Thereby, even when the absorption refrigeration apparatus 10 is started up, the ammonia liquid can be supplied to the high-pressure evaporator 30 and the low-pressure evaporator 32 without stagnation, and the objects 110 and 112 can be sufficiently cooled.

  The absorption refrigeration apparatus 10 is provided with the supply-side apparatus 12 and the output-side apparatus 14 separated from each other, and between the supply-side apparatus 12 and the output-side apparatus 14, an ammonia liquid that is a refrigerant and a high-concentration aqueous ammonia solution. And a low-concentration aqueous ammonia solution are respectively conveyed. The temperature of the ammonia liquid, the high-concentration aqueous ammonia solution, and the low-concentration aqueous ammonia solution, which are the refrigerants to be conveyed, may be any temperature. It is not necessary to provide heat insulation equipment for the absorbent solution transport pipe 102 and the second absorbent solution transport pipe 104. Furthermore, since the absorption refrigeration apparatus 10 uses thermal energy conversion including latent heat change, the transport amount of the heat medium can be reduced compared to sensible heat change. Thereby, the refrigerant | coolant conveyance pipe | tube 100, the 1st absorption solution conveyance pipe | tube 102, and the 2nd absorption solution conveyance pipe | tube 104 can be made compact compared with the cold water conveyance in the case of outputting the same cooling output. Furthermore, since the transport amount of the heat medium can be reduced, the solution pump power for transport can be reduced as compared with cold water transport when the same cooling output is output.

  When the supply capacity of the supply side device 12 is adjusted in accordance with the output performance of the output side device 14 for the purpose of suppressing excess equipment due to the excess capacity of the supply side device 12, the refrigerant buffer tank 20 Acts as a buffer. For example, even when the output of the cooled object in the high-pressure evaporator 30 exceeds the supply capability of the supply-side device 12 and temporarily increases, the ammonia liquid stored in the refrigerant buffer tank 20 is removed from the high-pressure evaporator. 30 can be accommodated. Thus, when adjusting the supply capability of the supply side device 12 according to the output performance of the output side device 14, by providing the refrigerant buffer tank 20, excessive facilities due to the excess capability of the supply side device 12 are suppressed. However, the risk of running out of ammonia liquid as a refrigerant can be reduced.

  FIG. 7 shows a partial schematic diagram of another absorption refrigeration apparatus 16 according to the present embodiment. In FIG. 7, the same elements as those of FIG. The absorption refrigeration apparatus 16 shown in FIG. 7 further includes two absorption solution buffer tanks 22 that are provided in the second absorption solution transport pipe 104 and store an aqueous ammonia solution having a low ammonia concentration, and two valves 80.

  The two absorbing solution buffer tanks 22 are respectively provided between the pressure reducing valve 86 and the absorber 40 and between the pressure reducing valve 86 and the absorber 42 in the second absorbing solution transport pipe 104. Further, the two valves 80 are provided between the absorbing solution buffer tank 22 and the absorber 40 and between the absorbing solution buffer tank 22 and the absorber 42, respectively. The absorption solution buffer tank 22 has the same configuration as that of the refrigerant buffer tank 20, and includes the buffer container 24 and the liquid level sensor 26 shown in FIG.

  Also in the absorption solution buffer tank 22, when starting up, the valve 80 is opened with the pressure reducing valve 86 closed, and the low concentration aqueous ammonia solution stored in the absorption solution buffer tank 22 is absorbed. Supply to vessels 40 and 42. As a result, the low-concentration aqueous ammonia solution stored in the absorption solution buffer tank 22 diffuses into the absorption refrigeration apparatus 16. Then, after the cooling of the air is stopped, the solution pump 92 is driven and the supply side device 12 is operated with the pressure reducing valve 86 opened and the valve 80 closed, thereby diffusing into the absorption refrigeration device 16. The predetermined amount of the low-concentration aqueous ammonia solution is again stored in the absorption solution buffer tank 22.

  When the ammonia gas stays in the high-pressure evaporator 30, the low-pressure evaporator 32, the absorber 40, and the absorber 42, the internal pressure is increased by the ammonia gas in the high-pressure evaporator 30 or the low-pressure evaporator 32, and the ammonia liquid is gasified. It is suppressed. Thereby, the cooling of the objects 110 and 112 may be hindered.

  The absorption refrigeration apparatus 16 according to this embodiment includes an absorption solution buffer tank 22 that stores a low-concentration aqueous ammonia solution that absorbs ammonia gas generated by the high-pressure evaporator 30 and the low-pressure evaporator 32 when the absorption refrigeration apparatus 16 is started up. including. Each of the buffer tanks 22 for absorbing solution absorbs a low-concentration aqueous ammonia solution that absorbs ammonia gas generated in the high-pressure evaporator 30 and the low-pressure evaporator 32 when the absorption refrigeration apparatus 16 is started up. To supply. Thereby, it is possible to prevent the ammonia gas from staying in the high-pressure evaporator 30, the low-pressure evaporator 32, the absorber 40 and the absorber 42, and the high-pressure evaporator 30 and the low-pressure evaporator 32 are the objects 110 and 112. Can be cooled sufficiently.

  FIG. 8 is a schematic cross-sectional view of another refrigerant buffer tank 28 according to the present embodiment. In FIG. 8, the same elements as those in FIG. The refrigerant buffer tank 28 shown in FIG. 8 further includes a solution pump 96 and a refrigerant transport pipe 108 that enters the buffer container 24.

  One end of the refrigerant transport pipe 108 enters the buffer container 24, and the other end is connected to the high-pressure evaporator 30 and the low-pressure evaporator 32. The solution pump 96 is a refrigerant transport pipe 108 and is provided between the refrigerant buffer tank 28 and the branching portion 109 between the high-pressure evaporator 30 and the low-pressure evaporator 32. The solution pump 96 conveys the ammonia liquid stored in the buffer container 24 to the high-pressure evaporator 30 and the low-pressure evaporator 32. Thus, the solution pump 96 is provided, and the ammonia liquid stored in the refrigerant buffer tank 28 is conveyed to the high-pressure evaporator 30 and the low-pressure evaporator 32. Thereby, the ammonia liquid to the high pressure evaporator 30 and the low pressure evaporator 32 can be stably supplied.

  In this embodiment, the supply side apparatus 12 and the output side apparatus 14 showed the example provided spaced apart. However, the supply-side device 12 and the output-side device 14 do not have to be separated from each other. For example, the supply-side device 12 and the output-side device 14 can be applied to the same room.

  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.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

DESCRIPTION OF SYMBOLS 10, 16 Absorption refrigeration apparatus, 12 Supply side apparatus, 14 Output side apparatus, 20, 28 Refrigerant buffer tank, 22 Buffer tank for absorption solution, 24 Buffer container, 26 Liquid level sensor, 30 High pressure evaporator, 32 Low pressure evaporator , 34, 36 Thermometer, 40, 42 Absorber, 50, 52 Generator, 54, 56 Rectifier, 60 Condenser, 70 Heat exchanger, 80 Valve, 82, 84 Expansion valve, 86 Pressure reducing valve, 88 Reverse Stop valve, 92, 96 Solution pump, 94 Reflux pump, 100, 108 Refrigerant transport pipe, 102 First absorbent solution transport pipe, 104 Second absorbent solution transport pipe, 106 Connecting part, 109 Branch part, 110, 112 Object , 114 Cooling water, 116, 118 Waste heat, 120 Cooling device

Claims (10)

A generator that contains an absorbing solution having a high refrigerant concentration, heats the refrigerant absorbed in the absorbing solution, and generates refrigerant vapor and an absorbing solution having a low refrigerant concentration;
A condenser connected to the generator to condense the refrigerant vapor into a liquid refrigerant;
An evaporator that evaporates the liquid refrigerant generated in the condenser and cools an object;
A refrigerant transport pipe connected to the condenser and the evaporator to form a path through which the refrigerant flows;
An absorber connected to the evaporator to absorb the refrigerant vapor in the absorbing solution having a low refrigerant concentration to form the absorbing solution having a high refrigerant concentration;
A first absorbent solution transport pipe connected to the generator and the absorber and forming a path through which the absorbent solution having a high refrigerant concentration flows;
A second absorbent solution transport pipe connected to the generator and the absorber and forming a path through which the absorbent solution having a low refrigerant concentration flows;
A refrigerant buffer tank that is provided in the refrigerant conveyance pipe and stores the liquid refrigerant;
An absorption refrigeration apparatus comprising: A solution pump provided in the absorbent solution transport pipe, for transporting the absorbent solution;
The absorption refrigeration apparatus according to claim 1, wherein after the cooling of the object is stopped, the solution pump is driven until a predetermined amount of the liquid refrigerant is stored in the buffer tank for refrigerant.   The absorption refrigeration apparatus according to claim 2, further comprising an absorption solution buffer tank provided in the second absorption solution transport pipe and storing the absorption solution having a low refrigerant concentration.   4. The solution pump according to claim 3, wherein, after the cooling of the object is stopped, the solution pump is driven until a predetermined amount of the absorbing solution having a low refrigerant concentration is stored in the absorbing solution buffer tank. 5. Absorption refrigeration equipment. The condenser and the generator are provided on a supply side of exhaust heat supplied to the generator,
The evaporator and the absorber are provided on the output side of the cooled object,
The absorption refrigeration apparatus according to any one of claims 1 to 4, wherein the condenser and the generator are provided apart from the evaporator and the absorber.   The absorption refrigeration apparatus according to claim 5, wherein the liquid refrigerant is transported from the condenser to the evaporator through the refrigerant transport pipe due to a difference in internal pressure between the condenser and the refrigerant buffer tank.   The absorption refrigeration apparatus according to claim 6, comprising a plurality of the evaporators having different internal pressures, wherein the plurality of evaporators cool the plurality of objects to different temperatures.   The absorption refrigeration apparatus according to claim 7, wherein a plurality of the absorbers are provided corresponding to the internal pressure of the evaporator.   The absorption refrigeration apparatus according to claim 8, further comprising a connecting portion that connects discharge ports of the plurality of absorbers, and a check valve provided on the absorber side of the connecting portion.   The absorption refrigeration apparatus according to any one of claims 5 to 9, wherein each of the generators is provided corresponding to the number of the exhaust heat supplied to the generator.

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