JP2008014598A - Bleeder for compression type refrigerating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bleeder for a compression-type refrigerating machine capable of dispensing with taking in and out of lubricant, saving power for an oil pump, and discharging a noncondensing gas in a bleeding tank to the outside of a system while reducing the wear amount of a refrigerant. <P>SOLUTION: In this compression-type refrigerating machine 1-1, a compressor 13, a condenser 17 and an evaporator 11 are connected by refrigerant piping 21, the bleeding tank 31 is connected with the condenser 17 by piping 33, and the noncondensing gas is collected in the bleeding tank 31. An absorption tank 35 filled with an absorbent 69 is connected with the bleeding tank 31 by piping 37, the noncondensing gas accumulated in the bleeding tank 31 is introduced to the absorption tank 35 to allow the refrigerant to be absorbed by the absorbent 69, and further the refrigerant vapor generated by being heated by an absorbent heater 71 is returned to a refrigerant circulating system of the evaporator 11 and the condenser 17 through piping 75 in regenerating the absorbent 69. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an extraction device for a compression refrigerator.

  Conventionally, a compression refrigerator (vapor compression refrigerator) is configured by connecting a compressor driven by an electric motor, a condenser, and an evaporator with a refrigerant pipe. And the non-condensable gas in the refrigerating cycle of a compression-type refrigerator accumulates in a condenser when this refrigerator is operated. This is because the space between the condenser and the evaporator is sealed with the refrigerant liquid liquefied at the outlet of the condenser. The non-condensable gas accumulated in the condenser increases the compression ratio during the operation of the refrigerator and consumes useless power. For this reason, conventionally, an extraction device for extracting non-condensable gas from the refrigeration cycle of the compression refrigerator has been developed.

For extracting non-condensable gas, a technique for reducing the refrigerant concentration in the mixed gas of non-condensable gas and refrigerant vapor by using lubricating oil as an absorbent that absorbs the refrigerant is disclosed in Patent Documents 1 and 2, for example. . Although these reduce the refrigerant partial pressure by absorbing oil, the oil used is a lubricating oil used in a lubricating system such as a bearing of a refrigerator or a speed increaser. Since the bearing and the gearbox are sealed in the refrigerator together with the refrigerant, the refrigerant is dissolved in the lubricating oil. In order to maintain (prevent) the viscosity of the lubricating oil, the refrigerant concentration does not rise above a predetermined value. However, since the viscosity is adjusted to a target value, the refrigerant partial pressure is relatively high. Therefore, the amount of refrigerant discharged tends to increase. Further, the place where the regeneration of the lubricating oil (reduction of the refrigerant concentration) is performed is in the lubricating oil circulation system, and the lubricating oil is taken into and out of the extraction tank by the lubricating oil pump. In addition, special control such as control of the oil flow in and out or the liquid level in the tank is required.
Japanese Patent Publication No. 1-55397 JP-A-5-10636

  The present invention has been made in view of the above-mentioned points, and its purpose is to eliminate the need to put in and take out lubricating oil, to reduce the power of the oil pump, and to reduce the amount of non-condensable gas in the extraction tank by reducing the amount of refrigerant consumed. Another object of the present invention is to provide a bleeder for a compression type refrigerator that can be discharged out of the system.

According to the first aspect of the present invention, the compressor, the condenser, and the evaporator are connected by a refrigerant pipe that circulates the refrigerant, and a non-condensable gas accumulated in the condenser is connected to the condenser by connecting an extraction tank. In a compression refrigerator that collects in an extraction tank, an absorption tank filled with an absorbent is connected to the extraction tank, non-condensable gas accumulated in the extraction tank is introduced into the absorption tank, and a refrigerant is supplied to the absorbent. A refrigerant refrigerating machine that absorbs and regenerates the absorbent, and returns the refrigerant vapor generated by heating with an absorbent heater provided in the absorption tank to the refrigerant circulation system of the evaporator and condenser. In the bleeder.
An economizer may be further installed in the refrigerant circulation system.

The invention according to claim 2 of the present application is the compression type bleeder of claim 1, wherein the absorbent heater of the absorption tank is the electric heater or the heat side of a heat pump. It is in the extraction device of the refrigerator.
The cold side of the heat pump may be air, or the refrigerant of the refrigerator condenser, or the refrigerant vapor or condensed liquid from the condenser of the extraction tank may be used.

According to a third aspect of the present invention, in the bleeder of the compression refrigeration machine according to the first aspect, an absorbent cooler is provided in the absorption tank, and when non-condensable gas is discharged from the bleed tank to the absorption tank, A bleeder for a compression type refrigerator is characterized in that the refrigerant vapor is absorbed while the absorbent cooler is operated to cool the absorbent.
The absorbent cooler preferably starts operating a predetermined time before the start of the non-condensable gas discharge operation.

  The invention according to claim 4 of the present application is the bleeder of the compression refrigerator according to claim 3, wherein the refrigerant liquid from the condenser is received on the cooling side of the absorbent cooler, and the absorbent on the cooled side is received. The refrigerant liquid is evaporated by the heat of the refrigerant, and the refrigerant vapor or the gas-liquid mixture is led to the evaporator or an economizer installed between the condenser and the evaporator. In the bleeder.

  The invention according to claim 5 of the present application is the bleeder of the compression refrigerator according to claim 3, wherein the absorbent cooler is a cold side of a heat pump capable of switching between a hot side and a cold side, and the absorbent At the time of regeneration, the bleeder of the compression refrigeration machine is characterized in that it is switched to the warm side and used as the absorbent heater.

  The invention according to claim 6 of the present application is the compression chiller extraction device according to any one of claims 1 to 5, wherein the non-condensable gas of the condenser is placed between the condenser and the extraction tank. The present invention resides in a bleeder for a compression type refrigerator having a bleeder compressor for compression.

  The invention according to claim 7 of the present application is the bleeder for a compression refrigeration machine according to claim 6, wherein a gas cooler is provided in the bleed tank, and a refrigerant liquid from the condenser is provided on the cooling side of the gas cooler. And the evaporated refrigerant vapor or gas-liquid mixture is returned to the condenser, returned to an economizer installed between the condenser and the evaporator, or returned to the evaporator. It is in the extraction device of the type refrigerator.

  The invention according to claim 8 of the present application is the bleeder for a compression refrigeration machine according to any one of claims 1 to 5, wherein a gas cooler is provided in the bleed tank, and a cooling side of the gas cooler is provided on the cooling side. In the extraction device of the compression type refrigerator, the refrigerant liquid from the condenser is introduced, and the evaporated refrigerant vapor or gas-liquid mixture is returned to the evaporator.

  Since an absorbent heater is provided in the absorption tank, it is not necessary to put in and out the lubricating oil as in the conventional case, so that the power of the oil pump that circulates the lubricating oil can be saved. Further, it is possible to improve the absorption capacity and reduce the amount of discharged refrigerant by adjusting the refrigerant concentration so that the vapor pressure of the refrigerant is not more than a predetermined value without considering the viscosity as the lubricating oil.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 is an overall schematic configuration diagram showing a compression refrigerator 1-1 configured by using the first embodiment of the present invention. The compression refrigerator 1-1 shown in the figure is a compression refrigerator that performs a vapor compression refrigeration cycle, and is composed of a closed system that encloses a refrigerant, and takes heat from cold water (a fluid to be cooled). An evaporator 11 that evaporates the refrigerant and exhibits a refrigeration effect, a compressor 13 that is rotationally driven by an electric motor (driving machine) 15 to compress the refrigerant vapor into high-pressure steam, and the high-pressure steam is cooled water (cooling fluid). The condenser 17 that cools and condenses the refrigerant and the expander 19 that decompresses and expands the condensed refrigerant and sends it to the evaporator 11 are connected by a refrigerant pipe 21 that circulates the refrigerant. Further, the compression refrigerator 1-1 includes a control device (control means) (not shown) that performs drive control of the electric motor 15 and various pumps described below, open / close control of various open / close means, and the like.

  Further, in the compression refrigerator 1-1, an extraction tank 31 is connected to the condenser 17 by a pipe 33, and an absorption tank 35 is connected to the extraction tank 31 by a pipe 37. A bleed compressor 39 is connected in the pipe 33, and a valve V 1 is connected in the pipe 37. A pipe 41 that cools the electric motor 15 with the refrigerant of the condenser 17 and returns to the condenser 17 is attached to the condenser 17, and a refrigerant pump 43 is installed in the pipe 41. On the discharge side of the refrigerant pump 43, the pipe 45 is branched, and further, the tip is branched by pipes 47 and 49, which are respectively introduced into the extraction tank 31 and the absorption tank 35. The cooling side of the gas cooler 51 and the absorbent cooler 53, respectively. The cooling side of the gas cooler 51 is connected to the condenser 17 by a pipe 55, and the cooling side of the absorbent cooler 53 is connected to the evaporator 11 by a pipe 57.

  A pipe 65 connected from the extraction tank 31 to the refrigerant pipe 21 between the condenser 17 and the evaporator 11 is attached to the lower part of the extraction tank 31. The bleed tank 31 has a pressure detection means 59 for detecting the gas pressure inside it, a temperature detection means 61 for detecting the temperature of the refrigerant liquid inside, and a level switch (liquid level detection) for detecting a predetermined liquid level. Means) 63 and a valve 67 connected to a pipe 65 controlled to be opened and closed by the level switch 63 are provided.

  On the other hand, the absorption tank 35 is filled with an absorbent 69 (in this embodiment, oil such as lubricating oil), and an absorbent heater 71 for heating the absorbent 69 is installed. The absorption tank 35 is provided with a pipe 73 and a valve V2 for discharging non-condensable gas into the atmosphere, and a pipe 75 and a valve V3 for returning the refrigerant to the evaporator 11 through the pipe 57. An expansion valve V0 is installed in the piping 47, and a valve V4 is installed in the piping 49. As the absorbent 69, the same lubricant as the bearing oil of the compressor 13 is preferable if it may leak from the absorption tank 35 into the refrigeration cycle for some reason. However, in terms of absorption and heat transfer, low viscosity (lubricant) oil is suitable for the absorbent, and it is reasonable to use a lubricant with the viscosity adjusted to a low level with the same type (same system) of lubricating oil. .

  The operation of the extraction device of the compression refrigerator 1-1 configured as described above will be described. The non-condensable gas in the condenser 17 is sucked and compressed by the extraction compressor 39 together with the refrigerant vapor and collected in the extraction tank 31. Thereby, the influence of the non-condensable gas on the condenser 17 can be reduced. On the other hand, at this time, a part of the refrigerant liquid in the condenser 17 is supplied to the cooling side of the gas cooler 51 through the expansion valve V0 and evaporated by the refrigerant pump 43, and the gas in the extraction tank 31 is cooled to remove the refrigerant in the gas. After condensing, it is returned to the condenser 17. Since it is compressed by the extraction compressor 39, the extraction tank 31 can condense the refrigerant at a temperature higher than the condenser temperature level. The condensed refrigerant is returned to the refrigerator circulation system by the pipe 65. At that time, the valve 67 is opened and closed by the level switch 63 so that the coolant level at a predetermined water level is maintained in the extraction tank 31, and the non-condensable gas in the extraction tank 31 is prevented from flowing out to the pipe 65 side by the liquid seal. I have to. In this embodiment, the liquid level is controlled by the level switch 63 and the valve 67, but the liquid level may be controlled using other means such as a float valve.

  On the other hand, as described above, oil is held in the absorption tank 35 as the absorbent 69, and after the absorbent 69 is heated and regenerated, it is left for a long time with the valves V1, V2, V3, and V4 closed to the vicinity of room temperature. It is decreasing. Then, the concentration state of the non-condensable gas is determined from, for example, the extraction tank pressure by the pressure detection unit 59 and the condensed refrigerant temperature in the extraction tank 31 by the temperature detection unit 61. The operation of discharging the non-condensable gas from the extraction tank 31 to the absorption tank 35 is started (or the operation of discharging the gas is performed when the extraction tank 31 reaches a predetermined pressure). For example, the degree of collection of non-condensable gas is determined from the extraction tank pressure P0 and the condensed refrigerant temperature T in the extraction tank 31, and when it is determined that a predetermined amount has been collected, the gas discharge operation is started (the refrigerant saturation temperature T0 relative to the pressure P0). Operation when the difference ΔT = T0−T with the refrigerant liquid temperature T is greater than or equal to a predetermined value, or the difference ΔP = P0−P between the extraction tank pressure P0 and the saturation pressure P with respect to the refrigerant liquid temperature T is greater than or equal to the predetermined value (ΔP becomes the partial pressure of the non-condensable gas)) or the gas discharge operation is started when the pressure P0 is equal to or higher than a predetermined value. Alternatively, the gas discharge operation is started at every predetermined operation time interval.

  First, the valve V4 is opened, the refrigerant liquid from the condenser 17 is supplied to the cooling side of the absorbent cooler 53 and evaporated, and the temperature of the absorbent 69 is lowered. Then, after a predetermined time or after the oil temperature reaches a predetermined value, the valve V1 is opened, and the gas in the extraction tank 31 is introduced into the absorption tank 35. The introduced non-condensable gas and refrigerant vapor form bubbles from the bottom of the absorption tank 35 and rise in the absorbent 69, and the refrigerant vapor is absorbed by the absorbent 69. After a predetermined time or after the pressure of the bleed tank 31 drops to a predetermined value, the valves V1 and V4 are closed. The valve V4 may be closed immediately after the valve V1 is opened. In this case, the refrigerant liquid remaining on the cooling side of the absorbent cooler 53 exhibits a cooling effect. The absorption of the refrigerant vapor ends almost simultaneously with the closing of the valve V1, but a slight time may be taken. Thereafter, the valve V2 is opened, and noncondensable gas is released to the atmosphere. The pressure after absorption in the absorption tank 35 can be estimated from the pressure in the extraction tank 31, and it is judged that the pressure is higher than the atmospheric pressure. However, for the sake of safety, the check valve 77 prevents the air from entering. . The absorption tank 35 may also be provided with pressure detecting means such as a pressure switch or a pressure sensor, and the valve V2 may be opened after confirming that the atmospheric pressure is exceeded. After a predetermined time or when the pressure is lowered to a predetermined pressure and it is determined that exhaust is complete, the valve V2 is closed and the discharge operation is completed. The valve V2 may be opened before the valve V1 is closed, and the noncondensable gas may be discharged while absorbing the refrigerant vapor. In this case, the movement amount of the noncondensable gas from the extraction tank 31 to the absorption tank 35 is increased. Can do. The closing timing of the valve V1 is preferably performed by time or the pressure of the extraction tank 31.

  When it is determined that the absorption capacity of the absorption tank 35 is sufficient, the gas discharge operation may be started again after waiting for the non-condensable gas to be accumulated in the extraction tank 31. After a decrease in the absorption capacity or after a predetermined number of times, the operation moves to a regeneration operation of the absorbent (oil) 69. The regeneration operation may be performed every discharge operation. In the regeneration operation, the absorbent 69 in the absorbent tank 35 is heated by the absorbent heater 71 while the valves V1, V2, V3, and V4 are closed. Then, the valve V3 is opened, the refrigerant in the absorbent 69 is evaporated and expelled to the evaporator 11 and the like. The temperature of the absorbent 69 rises to a predetermined temperature, and it is determined that regeneration is complete. Instead of judging by temperature, it can be judged that heating is completed.

  As described above, this compression refrigerator 1-1 introduces a gas having a high refrigerant partial pressure in the extraction tank 31 connected to the condenser 17 into the absorption tank 35 filled with the absorbent 69 intermittently. Then, after the refrigerant is absorbed by the absorbent 69 to reduce the refrigerant partial pressure, the non-condensable gas is released to the atmosphere, and the absorbent 69 is heated by the absorbent heater 71 after one or more releases to the atmosphere. The refrigerant is regenerated and the refrigerant generated at the time of regeneration is returned to the refrigerant circulation system of the refrigerator. In other words, the compression refrigerator 1-1 collects the non-condensable gas together with the refrigerant vapor from the condenser 17 in the extraction tank 31, condenses the refrigerant and returns it to the refrigerating machine circulation system, and the non-condensable gas enters the extraction tank 31. On the other hand, the refrigerant remains as a partial pressure corresponding to the condensation pressure (saturation pressure with respect to the condensation temperature), and if the gas in the extraction tank 31 is released (exhaust) to the outside as it is, the refrigerant is also released together with the noncondensable gas. Therefore, after making it contact with the absorber 69 of the absorption tank 35 and reducing a refrigerant vapor pressure, it is set as the structure discharge | released to air | atmosphere. As a result, it is possible to reduce the amount of wear of the refrigerant and release the non-condensable gas outside the system.

[Second Embodiment]
FIG. 2 is an overall schematic configuration diagram showing a compression type refrigerator 1-2 configured using the second embodiment of the present invention. In the compression refrigeration machine 1-2 shown in the figure, the same or corresponding parts as those in the compression refrigeration machine 1-1 shown in FIG. The items other than those described below are the same as those of the compression refrigerator 1-1 shown in FIG. The difference between the compression type refrigerator 1-1 and the compression type refrigerator 1-1 is that the extraction compressor 39 is omitted and the refrigerant supplied from the condenser 17 to the cooling side of the gas cooler 51 by the pipe 47. Is returned to the evaporator 11 by the pipe 55. The method of collecting non-condensable gas in the extraction tank 31 is different from that of the compression refrigerator 1-1.

  That is, the compression type refrigerator 1-2 guides the refrigerant liquid from the condenser 17 through the expansion valve V0 to the cooling side of the gas cooler 51 of the extraction tank 31, evaporates on the cooling side of the gas cooler 51, and then evaporates. It is configured to lead to the vessel 11. The cooling side of the gas cooler 51 is at the same low temperature as the evaporator 11. Since the refrigerant vapor from the condenser 17 to the extraction tank 31 by the pipe 33 is condensed on the cooled side of the gas cooler 51, the refrigerant vapor flows from the condenser 17 to the extraction tank 31 through the pipe 33 and is not condensed. The gas flows into the extraction tank 31 together with the refrigerant vapor. The refrigerant is condensed and returns to the refrigerator circulation system through the pipe 65. Non-condensable gas does not flow out by the liquid seal (holding the refrigerant liquid level in the extraction tank 31). In the case of this embodiment, the condenser refrigerant liquid is supplied to the cooling side of the gas cooler 51 of the extraction tank 31 via the refrigerant pump 43, but the condenser pressure and the evaporator are not via the refrigerant pump 43. Even if it supplies with the difference of pressure, it does not interfere.

  When the amount of non-condensable gas is collected from, for example, the pressure of the extraction tank 31 and the temperature of the condensed refrigerant in the extraction tank 31, or from the pressure of the extraction tank 31, the gas discharge operation to go into. The gas discharge operation and the absorbent regeneration operation are the same as in the case of the compression refrigerator 1-1.

  That is, the compression type refrigerator 1-1 has a bleed compressor 39 provided between the condenser 17 and the bleed tank 31 and collects refrigerant vapor and non-condensable gas while compressing (compressed bleed method). In this compression type refrigerator 1-2, a gas cooler 51 having a low temperature is provided in the extraction tank 31, the refrigerant vapor pressure in the extraction tank 31 is lowered, and the non-condensable gas is collected on the flow of steam. Method (thermal purge method).

[Third Embodiment]
FIG. 3 is an overall schematic configuration diagram illustrating a compression refrigerator 1-3 configured using the third embodiment of the present invention. In the compression refrigeration machine 1-3 shown in the same figure, the same or corresponding parts as those of the compression refrigeration machine 1-1 shown in FIG. The items other than those described below are the same as those of the compression refrigerator 1-1 shown in FIG. This compression refrigerator 1-3 is different from the compression refrigerator 1-1 in that an economizer 23 is installed in the refrigerant pipe 21 between the condenser 17 and the evaporator 11 and separated by the economizer 23. And the refrigerant supplied to the cooling side of the gas cooler 51 from the condenser 17 by the pipe 47 through the pipe 55 is sucked into the middle of the compression stage of the compressor 13 having multiple stages (two stages). The point which returned to the economizer 23 and the point which returned the refrigerant | coolant supplied to the cooling side of the absorber cooler 53 from the condenser 17 by the piping 49 to the economizer 23 by the piping 57. The compression refrigerator 1-1 changes the evaporating temperature on the cooling side of the gas cooler 51 of the extraction tank 31 and the temperature level of the suction cooler 53 of the suction tank 35.

  That is, the compression refrigerator 1-3 supplies the refrigerant liquid from the condenser 17 to the cooling side of the gas cooler 51 of the extraction tank 31 and communicates the outlet on the cooling side of the gas cooler 51 to the economizer 23. Therefore, it evaporates at the temperature level of the economizer 23. By reducing the evaporation temperature on the cooling side of the gas cooler 51, the condensation temperature and the condensation pressure in the extraction tank 31 can be lowered, and the refrigerant vapor partial pressure is lowered. Accordingly, the amount of refrigerant in the non-condensable gas sent to the absorption tank 35 can be reduced. However, since the refrigerant vapor is returned from the cooling side of the gas cooler 51 to the economizer 23, the work amount of the second stage compressor 13b is increased.

  Further, the outlet on the cooling side of the absorbent cooler 53 of the absorption tank 35 is changed from the evaporator 11 to the economizer 23. If the temperature level rises and the absorbent concentration is the same, the absorption capacity decreases, but the compression work of the first stage compressor 13a can be reduced. The absorption capacity is adjusted by adjusting the absorbent concentration (heating temperature during regeneration). Various combinations of the refrigerant return position from the cooling side of the gas cooler 51 of the extraction tank 31 and the refrigerant return position from the cooling side of the absorbent cooler 53 of the absorption tank 35 are considered as follows. The gas discharge operation and the absorbent regeneration operation are substantially the same as those of the compression refrigerator 1-1.

[Fourth Embodiment]
FIG. 4 is an overall schematic configuration diagram showing a compression refrigerator 1-4 configured using the fourth embodiment of the present invention. In the compression refrigeration machine 1-4 shown in the figure, the same or corresponding parts as those of the compression refrigeration machine 1-1 shown in FIG. The items other than those described below are the same as those of the compression refrigerator 1-1 shown in FIG. The difference between the compression refrigerator 1-1 and the compression refrigerator 1-1 in the compression refrigerator 1-4 is that, instead of the absorbent heater 71 and the absorber cooler 53 used in the compression refrigerator 1-1, the hot side and cold heat are used. The heat pump (absorbent heater / cooler) 79 capable of reversing the side is installed. That is, the absorbent heater 71 and the absorbent cooler 53 of the absorption tank 35 are different from the compression refrigerator 1-1. Like the compression refrigerator 1-4, the heat pump 79 capable of reversing the hot side and the cold side makes the absorption tank 35 the hot side, thereby serving as an absorbent heater (cooling at this time) The side may be the outside air, the refrigerant of the extraction tank 31, the condenser of the turbo chiller, etc., and the outside air is adopted in the figure.) On the contrary, the absorption tank 35 is set to the cold side, thereby serving as an absorbent cooler. (At this time, the heat side = the heat release side may be the outside air, the refrigerant in the extraction tank 31, the condenser of the turbo refrigerator, etc., and the outside air is used in the figure). The type of heat pump is not particularly limited, and it may be a compression heat pump or an electronic type using a Peltier element.

[Fifth Embodiment]
FIG. 5 is an overall schematic configuration diagram showing a compression refrigerator 1-5 configured by using the fifth embodiment of the present invention. In the compression refrigeration machine 1-5 shown in the figure, the same or corresponding parts as those of the compression refrigeration machine 1-1 shown in FIG. The items other than those described below are the same as those of the compression refrigerator 1-1 shown in FIG. The difference between the compression refrigerator 1-5 and the compression refrigerator 1-1 in the compression refrigerator 1-5 is that the refrigeration cycle of the compression refrigerator is doubled. ), The electric motor 15 and the bleeder of the present invention are shared. In this embodiment, the bleeder is connected to one (low pressure side) refrigeration cycle (A side).

  In a refrigerator having a double refrigeration cycle, there are two refrigeration cycles in one refrigerator. Therefore, the extraction device of the present invention may be applied to each cycle. However, as in this embodiment, the extraction system can be used for both cycles. The non-condensable gas collects in each of the two systems of condensers 17A and 17B. A connecting pipe 81 is provided between the high-pressure side condenser 17B and the low-pressure side condenser 17A to move a small amount of refrigerant vapor and non-condensable gas. If enabled, the non-condensable gas collects in the low pressure side condenser 17A. In order to consciously adjust the flow, a valve V5 may be provided in the communication pipe 81 and controlled. The low-pressure side condenser 17A and the extraction tank 31 are connected to perform extraction. As described above, various temperature levels of the gas cooler 51, the absorbent cooler 53, and the like can be selected.

  In this embodiment, the non-condensable gas is collected in the low-pressure side condenser 17A. However, it is also possible to provide a compressor in the connecting pipe 81 and increase the pressure to collect the non-condensable gas in the high-pressure side condenser 17B. The refrigerant between the two cycles tends to move from the high pressure side cycle to the low pressure side cycle through the seals of the electric motor 15 and the compressors 13A and 13B. It is also possible to move the noncondensable gas together with the refrigerant to collect the noncondensable gas in the high-pressure side condenser 17B.

[Sixth Embodiment]
FIG. 6 is an overall schematic configuration diagram of a compression refrigerator 1-6 configured using the sixth embodiment of the present invention. In the compression refrigerator 1-6 shown in the figure, the same reference numerals are given to the same or corresponding parts as those of the compression refrigerator 1-1 shown in FIG. Items other than those described below are the same as those in the embodiment shown in FIG. The compression refrigerator 1-6 differs from the compression refrigerator 1-1 in that a power recovery device 63 is installed in place of the expander 19.

  The power recovery device 63 used in this embodiment is a rotary power recovery expander that recovers the energy of the refrigerant flow from the condenser 17 to the evaporator 11, and has a nozzle and a turbine inside. Thus, the flow rate of the refrigerant liquid from the condenser 17 is increased and a swirling flow is applied, and this liquid flow is applied to the turbine to give a rotational force to the turbine. The power recovery device 63 includes a generator (power recovery machine) 65, and the generator 65 recovers the energy of the refrigerant flow as electric power. If the recovered electric power is supplied to the motor 15 and used for a part of the compression work, the input electric power (input power) from the outside can be reduced accordingly. Further, since the power is recovered from the refrigerant entering the evaporator 11 from the condenser 17, the enthalpy of the refrigerant entering the evaporator 11 is lowered, and thus the refrigerating capacity of the evaporator 11 is increased and the refrigeration effect is increased. .

  By the way, as the absorbent 69 used in each of the above-described embodiments, a lubricating oil compatible with the refrigerant is preferable. It may be the same as that used for the bearing of the refrigerator, or it may be the same system with a different viscosity. FIG. 7 shows the relationship between the refrigerant pressure and the refrigerant concentration of the absorbing solution, and FIG. 8 shows an example of the relationship between the dew point (refrigerant saturation temperature) and the absorbing solution (absorbent + refrigerant) temperature (refrigerant: R245fa, lubricating oil: polyol ester). ). Consider a case where this lubricating oil is used at a refrigerant concentration of 5%. When the refrigerant condensation temperature in the extraction tank 31 is 35 ° C., the saturation pressure is 213 kPa. However, when the mixed gas of the non-condensable gas and the refrigerant vapor is absorbed by contact with 10 ° C. and 5% lubricating oil, the dew point is −22. The refrigerant becomes 6 ° C. and a saturation pressure of 17 kPa, and the refrigerant contained in the mixed gas can be reduced to about 8%. This effect corresponds to setting the condensation temperature of the extraction tank 31 to −22.5 ° C. When the refrigerant is absorbed, the refrigerant concentration in the lubricating oil slightly increases. If the extraction tank 31 is about 5 liters and the amount of lubricating oil is about 2 kg, the concentration increases by about 0.3% and becomes 5.3% in one extraction operation (for 5 liters of tank). If the amount of lubricating oil is increased, the change in concentration can be suppressed. In order to return the refrigerant concentration of the lubricating oil to 5%, the lubricating oil may be heated to about 58 ° C. by connecting the absorption tank 35 to the evaporator 11 during regeneration and setting the dew point to about 6 ° C.

The following various flows are used to supply the refrigerant liquid to the cooling side of the gas cooler 51 of the extraction tank 31 and to discharge the refrigerant vapor (which may be mixed with liquid) from the cooling side of the gas cooler 51. The present invention can be applied.
(1) Refrigerant liquid of condenser 17 → refrigerant pump 43 → gas cooler 51 → condenser 17 (first embodiment, fourth embodiment, fifth embodiment, sixth embodiment)
(2) Refrigerant liquid in condenser 17 → (refrigerant pump 43) → gas cooler 51 → economizer 23 (third embodiment)
(3) Refrigerant liquid of condenser 17 → (refrigerant pump 43) → gas cooler 51 → evaporator 11 (second embodiment)
(4) Refrigerant liquid of economizer 23 → refrigerant pump 43 → gas cooler 51 → economizer 23
(5) Refrigerant liquid of economizer 23 → gas cooler 51 → evaporator 11
(6) Refrigerant liquid of evaporator 11 → refrigerant pump 43 → gas cooler 51 → evaporator 11

  The refrigerant pump 43 of (1), (2), (3) can also be used as a pump that sends the refrigerant liquid to the electric motor 15 for cooling the electric motor 15. In (2) and (3), the refrigerant can be supplied by the pressure difference without using the refrigerant pump 43. In (4) and (6), it is necessary to newly provide the refrigerant pump 43. Among these, the method of returning the refrigerant vapor (1) to the condenser 17 is efficient without increasing the compression work to the refrigerator. Next, the methods (2) and (4) for returning to the economizer 25 are efficient. All of (1) to (6) can be used for the compression bleed method, but (1) cannot be used for the thermal purge method, and (2) to (6) can be used. In the compression bleed system, it can be returned anywhere in the condenser 17, the economizer 25, the evaporator 11 or the refrigerant pipe 21 connecting them. In the thermal purge method, the refrigerant 11 is returned to the evaporator 11 or the refrigerant pipe 21 connected thereto. The method of returning to the condenser 17 does not apply a load to the refrigerator.

It is a whole schematic block diagram which shows the compression refrigerator 1-1. It is a whole schematic block diagram which shows the compression-type refrigerator 1-2. It is a whole schematic block diagram which shows the compression refrigerator 1-3. It is a whole schematic block diagram which shows the compression-type refrigerator 1-4. It is a whole schematic block diagram which shows the compression refrigerator 1-5. It is a whole schematic block diagram which shows the compression refrigerator 1-6. It is a figure which shows the example of the relationship between a refrigerant | coolant pressure and the refrigerant | coolant density | concentration of an absorption solution. It is a figure which shows the example of the relationship between a dew point and absorption solution temperature.

Explanation of symbols

1-1 Compression Refrigerator 11 Evaporator 13 Compressor 15 Electric Motor (Driver)
17 Condenser 19 Expander 21 Refrigerant Pipe 23 Economizer 31 Extraction Tank 35 Absorption Tank 39 Extraction Compressor 43 Refrigerant Pump 51 Gas Cooler 53 Absorbent Cooler 69 Absorbent 71 Absorbent Heater 1-2 Compressed Refrigerator 1-3 Compression type refrigerator 1-4 Compression type refrigerator 79 Heat pump 1-5 Compression type refrigerator 1-6 Compression type refrigerator

Claims (8)

In the compression type refrigerator that connects the compressor, the condenser, and the evaporator with a refrigerant pipe that circulates the refrigerant, and connects the extraction tank to the condenser and collects the non-condensable gas accumulated in the condenser in the extraction tank.
An absorption tank filled with an absorbent is connected to the extraction tank, non-condensable gas accumulated in the extraction tank is introduced into the absorption tank, and the refrigerant is absorbed by the absorbent.
A bleeder for a compression refrigeration machine, wherein, during regeneration of the absorbent, refrigerant vapor generated by heating with an absorbent heater provided in the absorption tank is returned to a refrigerant circulation system of the evaporator and condenser. In the bleeder of the compression refrigerator according to claim 1,
An extraction device for a compression type refrigerator, wherein the absorbent heater of the absorption tank is an electric heater or a heat side of a heat pump. In the bleeder of the compression refrigerator according to claim 1,
The absorption tank is provided with an absorbent cooler,
A bleeder for a compression refrigeration machine that absorbs refrigerant vapor while operating the absorbent cooler to cool the absorbent when discharging non-condensable gas from the bleed tank to the absorption tank. In the extraction apparatus of the compression refrigerator according to claim 3,
The refrigerant liquid from the condenser is received on the cooling side of the absorbent cooler, the refrigerant liquid is evaporated by the heat of the absorbent on the cooled side, and the refrigerant vapor or gas-liquid mixture is supplied to the evaporator or A bleeder for a compression type refrigerator, which is led to an economizer installed between the condenser and the evaporator. In the extraction apparatus of the compression refrigerator according to claim 3,
The absorbent cooler is a cold side of a heat pump capable of switching between a hot side and a cold side,
A bleeder for a compression refrigeration machine, wherein the absorbent heater is switched to the warm side during regeneration of the absorbent. In the extraction apparatus of the compression-type refrigerator in any one of Claims 1 thru | or 5,
A bleeder for a compression type refrigerator, wherein a bleed compressor for compressing a non-condensable gas of the condenser is provided between the condenser and the bleed tank. In the bleeder of the compression refrigerator according to claim 6,
A gas cooler is provided in the extraction tank,
An economizer in which the refrigerant liquid from the condenser is introduced to the cooling side of the gas cooler, and the evaporated refrigerant vapor or gas-liquid mixture is returned to the condenser or installed between the condenser and the evaporator. Or a bleeder for a compression type refrigerator, wherein the bleeder is returned to the evaporator. In the bleeder of the compression type refrigerator according to any one of claims 1 to 5,
A gas cooler is provided in the extraction tank,
A bleeder for a compression type refrigerator, wherein the refrigerant liquid from the condenser is introduced to the cooling side of the gas cooler, and the evaporated refrigerant vapor or gas-liquid mixture is returned to the evaporator.

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