JP2018141565A - Absorption type refrigeration system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorption type refrigeration system capable of starting an absorption type refrigerator in an environment in which a cooling water temperature is low.SOLUTION: An absorption type refrigeration system 1 includes: an absorption type refrigerator 21 for generating cold water; an engine for heating a heating medium to be supplied to a regenerator of the absorption type refrigerator 21; a cooling tower 25 for circulating the cooling water between a condenser and an absorber of the absorption type refrigerator 21; and a system controller 40 for performing control related to the absorption type refrigeration system 1. In this case, when determining a low-temperature state of the cooling water on the basis of a preset first determination temperature, the system controller 40 performs control to lower regeneration capacity of the regenerator.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an absorption refrigeration system.

  2. Description of the Related Art Conventionally, an absorption refrigeration system including an absorption chiller that obtains cold water used in external equipment by a circulation cycle using an evaporator, an absorber, a regenerator, and a condenser is known. In this type of absorption refrigeration system, when the absorption chiller is started, the temperature of the solution may be lower than the temperature of the solution during operation. For this reason, at the time of start-up, the amount of heat used in the regenerator may be larger than that during steady operation. Furthermore, when the temperature of the cooling water for cooling the absorption chiller is low, there is a problem that the heat consumption of the absorption chiller increases.

  For example, Patent Document 1 discloses an absorption heat pump that can be operated even when the temperature of the supplied cooling water is low. In this absorption heat pump, the cooling water supplied to the condenser is given heat other than the heat deprived from the refrigerant vapor, and the cooling water temperature rising device for raising the temperature of the cooling water, And a control device for adjusting and maintaining the concentration of the concentrated solution so as not to exceed a predetermined concentration.

Japanese Patent Laying-Open No. 2015-183967

  As described above, when heat exceeding the amount of heat on the heat source side is consumed in the absorption chiller, the heat source temperature falls below the operating temperature of the absorption chiller and is absorbed until the heat source temperature rises. The type refrigerator may be stopped. In this case, it stops until the heat source temperature rises again, and this cycle is repeated until the cooling water temperature and the solution temperature rise. Therefore, the temperature on the heat source side fluctuates greatly, and in the worst case, there is a problem that the heat source temperature does not recover and the absorption refrigerator cannot be started.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an absorption refrigeration system capable of starting an absorption chiller even in an environment where the cooling water temperature is low.

  In order to solve this problem, the present invention provides an absorption refrigeration system that supplies a cooled refrigerant to an external device that operates using the refrigerant. This absorption refrigeration system includes an absorption chiller that cools a refrigerant by a circulation cycle including an evaporator, an absorber, a regenerator, and a condenser, and a heat source that heats a heat medium supplied to the regenerator of the absorption refrigeration machine. A cooling tower that circulates cooling water between the condenser and the absorber of the absorption refrigeration machine, and a controller that controls the absorption refrigeration system, the controller being based on a preset determination temperature When the low temperature state of the cooling water is determined, control for reducing the regenerative capacity of the regenerator is performed.

  Here, in the present invention, the control for reducing the regeneration capability of the regenerator preferably limits the amount of the heat medium supplied from the heat source to the regenerator.

  In the present invention, it is preferable that the controller performs control to reduce the cooling amount of the cooling water by the cooling tower after finishing the control to reduce the regeneration capability of the regenerator.

  In the present invention, it is preferable that the controller restricts the solution flowing into the absorber after completing the control for reducing the regeneration capability of the regenerator.

  ADVANTAGE OF THE INVENTION According to this invention, even if it is an environment with low cooling water temperature, an absorption refrigerating machine can be started appropriately.

The block diagram which shows typically the absorption refrigeration system which concerns on this embodiment Configuration diagram schematically showing the configuration of an absorption refrigerator The flowchart which shows the control method of the absorption refrigeration system which concerns on this embodiment

  FIG. 1 is a configuration diagram schematically showing an absorption refrigeration system 1 according to the present embodiment. The absorption refrigeration system 1 according to the present embodiment heats a dilute solution of the absorption refrigeration machine 21 using the heat of a heat source. The first system 10, the second system 20, and the third system 30. And a system controller 40.

  The first system 10 is a system that recovers heat from a heat source, and includes an engine 11, a heat exchanger 12, an exhaust heat passage 13, a radiator 14, and an engine-side three-way valve 15.

  The engine 11 drives the generator 16, and is, for example, a reciprocating engine. In the absorption refrigeration system 1, the engine 11 corresponds to a heat source, and the exhaust heat of the engine 11 is recovered in the first system 10.

  The heat exchanger 12 heats the heat medium by exchanging heat between the exhaust heat of the engine 11 and the heat medium supplied to the second system 20.

  The exhaust heat passage 13 is a pipe that circulates the heat medium from the engine 11 through the heat exchanger 12 to the engine 11 again. Of the exhaust heat flow path 13, a flow path from the heat exchanger 12 to the engine 11 is referred to as a first exhaust heat flow path 13a, and a flow path from the engine 11 to the heat exchanger 12 is referred to as a second exhaust heat flow path 13b. The exhaust heat flow path 13 includes a third exhaust heat flow path 13c that passes through the radiator 14. One end of the third heat exhaust flow path 13c is located upstream of the first exhaust heat flow path 13a, and the other end is The first exhaust heat flow path 13a is connected to the downstream side.

  The radiator 14 is provided in the first exhaust heat flow path 13 a and radiates heat of the heat medium from the heat exchanger 12 toward the engine 11.

  The engine-side three-way valve 15 is disposed at a connection point between the third exhaust heat passage 13c and the first exhaust heat passage 13a. When the opening degree of the engine side three-way valve 15 is fully opened, the heat medium from the heat exchanger 12 bypasses the radiator 14 and flows to the engine 11. On the other hand, the ratio of the heat medium flowing to the radiator 14 increases as the opening degree of the engine side three-way valve 15 is limited.

  The 2nd system 20 is for obtaining the cold water used with the indoor unit 31 mentioned later, and is equipped with the absorption refrigerating machine 21, the heat-medium flow path 22, and the heat-medium pump 23. In the present embodiment, cold water is used in the indoor unit 31. However, the present invention is not limited to cold water, and other refrigerants may be used.

  FIG. 2 is a configuration diagram schematically showing the configuration of the absorption refrigerator 21. The absorption refrigerator 21 obtains cold water by a recycle cycle of a regenerator, a condenser, an evaporator, and an absorber. The absorption chiller 21 includes a regenerator 101, a condenser 102, an evaporator 103, and an absorber 104. The absorption refrigerator 21 is combined with a cooling tower 25 and a cooling water flow path 26.

  The regenerator 101 heats a dilute solution (solution having a low concentration of the absorbing solution) in which a refrigerant (for example, water) and lithium bromide (LiBr) serving as an absorbing solution are mixed. Hereinafter, the refrigerant vaporized is referred to as “refrigerant vapor”, and the refrigerant liquefied is referred to as “liquid refrigerant”. The regenerator 101 is provided with a heat medium flow path 22, and a dilute solution is sprayed on the heat medium flow path 22 and heated. The regenerator 101 generates a refrigerant vapor and a concentrated solution (a solution having a high concentration of absorption liquid) by releasing the vapor from the dilute solution by heating. A dilute solution is supplied from the absorber 104 to the regenerator 101 via the solution channel 29 (first solution channel 29a).

  The condenser 102 liquefies the refrigerant vapor supplied from the regenerator 101. In the condenser 102, a heat transfer tube 102a through which the cooling water cooled by the cooling tower 25 flows is provided. A cooling water channel 26 is connected to the heat transfer tube 102 a so that the cooling water can circulate between the heat transfer tube 102 a and the cooling tower 25. The evaporated refrigerant vapor is liquefied by the cooling water in the heat transfer tube 102a. The liquid refrigerant liquefied by the condenser 102 is supplied to the evaporator 103.

  The evaporator 103 evaporates the liquid refrigerant. In the evaporator 103, a cold water passage 32 connected to an indoor unit 31 described later is provided. Cold water heated by the indoor unit 31 flows through the cold water passage 32. Further, the inside of the evaporator 103 is in a vacuum state. For this reason, the evaporation temperature of water as a refrigerant is about 5 ° C. Therefore, the liquid refrigerant sprayed on the cold water passage 32 evaporates depending on the temperature of the cold water passage 32. On the other hand, the temperature of the cold water in the cold water flow path 32 is deprived due to evaporation of the liquid refrigerant. Thereby, the cold water flowing in the cold water flow path 32 is cooled, and the cooled cold water is supplied to the indoor unit 31.

  The absorber 104 absorbs the refrigerant evaporated in the evaporator 103. The concentrated solution is supplied from the regenerator 101 to the absorber 104 via the solution channel 29 (second solution channel 29b), and the evaporated refrigerant is absorbed by the concentrated solution to generate a diluted solution. In the absorber 104, a heat transfer tube 104a through which the cooling water cooled by the cooling tower 25 flows is provided. A cooling water flow path 26 is connected to the heat transfer tube 104 a so that the cooling water can circulate between the heat transfer tube 104 a and the cooling tower 25. Absorption heat generated by absorption of the refrigerant in the concentrated solution is removed by cooling water flowing through the heat transfer tube 104a. The dilute solution whose concentration is reduced by the absorption of the refrigerant is supplied to the regenerator 101 by the solution pump 104b. The heat transfer tube 104 a is connected to the heat transfer tube 102 a of the condenser 102 in order to share the cooling water of the cooling tower 25 with the condenser 102.

  In the present embodiment, a solution bypass channel 29c that bypasses the heat transfer tube 104a and supplies the concentrated solution supplied to the absorber 104 to the lower side of the heat transfer tube 104a is connected to the second solution channel 29b. ing. The solution bypass channel 29c is provided with a solution bypass valve 29c1 that switches the supply state (supply or cutoff) of the concentrated solution by opening and closing the solution bypass channel 29c. In the state where the solution bypass valve 29c1 is closed, the concentrated solution supplied from the regenerator 101 passes through the heat transfer tube 104a, so that the absorber 104 has a high absorption capacity. On the other hand, in the state in which the solution bypass valve 29c1 is opened, the concentrated solution supplied from the regenerator 101 increases the ratio of bypassing the heat transfer tube 104a. That is, the temperature drop of the evaporator 103 can be suppressed by limiting the solution flowing into the absorber 104.

  The cooling tower 25 supplies cooling water to the absorption chiller 21 and cools the cooling water warmed by the absorption chiller 21. The cooling tower 25 has, for example, a tank that stores cooling water at the bottom. This tank is supplied with water by upper and lower floats, and the tank stores a certain amount of cooling water. Moreover, the cooling tower 25 has the fan 25a and the heat exchange part 25b arrange | positioned under the said fan 25a in the upper part. The cooling water returned from the absorption chiller 21 is sprayed on the heat exchanging part 25b and cooled by passing through the heat exchanging part 25b. The cooling water cooled by the heat exchange unit 25b is stored in the tank.

  The cooling water channel 26 is a pipe that circulates the cooling water from the cooling tower 25 to the cooling tower 25 again through the absorber 104 and the condenser 102 of the absorption refrigerator 21. Among these, the flow path from the cooling tower 25 to the absorption chiller 21 is referred to as a first cooling water flow path 26a, and the flow path from the absorption chiller 21 to the cooling tower 25 is referred to as a second cooling water flow path 26b.

  The 1st cooling water flow path 26a is connected with the bottom part (bottom part of a tank) of the cooling tower 25, and the cooling water pump 27 is provided in this 1st cooling water flow path 26a. The cooling water pump 27 serves as a power source for circulating the cooling water. The 2nd cooling water flow path 26b is connected with the upper part (between the fan 25a and the heat exchange part 25b) of the cooling tower 25. FIG.

  Further, a cooling water bypass passage 26c that supplies the cooling water returning to the cooling tower 25 by bypassing the heat exchanging portion 25b is connected to the second cooling water passage 26b. A cooling water three-way valve 28 is disposed at a connection point between the second cooling water channel 26b and the cooling water bypass channel 26c. When the opening degree of the cooling water three-way valve 28 is fully opened, the cooling water from the absorption chiller 21 flows to the upper part of the cooling tower 25 and is supplied to the heat exchange unit 25b. On the other hand, as the opening degree of the cooling water three-way valve 28 is limited, the ratio of the cooling water flowing to the cooling water bypass passage 26c increases and the cooling capacity of the cooling tower 25 also decreases.

Further, the absorption chiller 21 includes a control unit 105. The control unit 105 includes a CPU (Central Processing Unit) and controls the entire absorption refrigerator 21. Moreover, this control part 105 becomes a structure which changes the control content regarding the absorption refrigerator 21 based on the control signal from the system controller 40 mentioned later.

  1 and 2, the heat medium flow path 22 is a pipe that circulates the heat medium from the heat exchanger 12 through the regenerator 101 of the absorption refrigerator 21 to the heat exchanger 12 again. Among these, the flow path from the heat exchanger 12 toward the regenerator 101 of the absorption refrigeration machine 21 is referred to as a first heat medium flow path 22 a, and the flow path from the regenerator 101 of the absorption refrigeration machine 21 toward the heat exchanger 12. Is referred to as a second heat medium flow path 22b. Further, the heat medium flow path 22 includes a third heat medium flow path 22c that bypasses the absorption refrigerator 21, and one end of the third heat medium flow path 22c is connected to the first heat medium flow path 22a. The other end is connected to the second heat medium flow path 22b.

  A heat medium pump 23 is provided in the first heat medium flow path 22 a of the heat medium flow path 22. The heat medium pump 23 serves as a power source for circulating the heat medium.

  A heat medium three-way valve 24 is provided at the connection point between the second heat medium flow path 22b and the third heat medium flow path 22c. When the opening degree of the heat medium three-way valve 24 is fully opened, the heat medium from the heat exchanger 12 flows to the heat exchanger 12 via the regenerator 101. On the other hand, as the opening degree of the heat medium three-way valve 24 is limited, the ratio of the heat medium flowing to the third heat medium flow path 22c, that is, the ratio of the heat medium bypassing the regenerator 101 increases. That is, when the heat medium three-way valve 24 is set on the regenerator 101 side (when fully opened), the entire amount of the heat medium from the heat exchanger 12 is supplied to the regenerator 101, so that the regenerator 101 is high. It becomes regenerative ability. On the other hand, when the heat medium three-way valve 24 is set to the bypass side (when the opening degree is limited), the supply of the heat medium to the regenerator 101 is limited, so that the regeneration capability of the regenerator 101 is reduced. It will be.

  The third system 30 supplies cold water obtained by the absorption chiller 21 to the indoor unit 31, and includes an indoor unit 31, a cold water flow path 32, and a cold water pump 33.

  The indoor unit 31 is connected to the cold water flow path 32 and is provided indoors. The indoor unit 31 is an air conditioner, and performs heat exchange between cold water supplied from the absorption chiller 21 and air taken in from the room. By this heat exchange, heat is taken from the air to the cold water, thereby cooling the air. The indoor unit 31 blows the cooled air into the room.

  The cold water flow path 32 is a pipe that circulates cold water from the indoor unit 31 through the evaporator 103 of the absorption refrigerator 21 to the indoor unit 31 again. Among these, the flow path from the evaporator 103 of the absorption chiller 21 to the indoor unit 31 is referred to as a first cold water flow path 32a, and the flow path from the indoor unit 31 to the evaporator 103 of the absorption chiller 21 is second. This is referred to as a cold water passage 32b.

  The chilled water pump 33 is provided in the second chilled water flow channel 32b of the chilled water flow channel 32, and serves as a power source for circulating the chilled water.

  The system controller 40 controls the entire absorption refrigeration system 1. Signals from various sensors are input to the system controller 40 as control inputs. The system controller 40 performs various calculations based on the control input, and outputs a control output according to the calculation result to each part of the absorption refrigeration system 1. As the system controller 40, a microcomputer mainly composed of a CPU, a ROM, a RAM, and an I / O interface can be used.

  The heat medium inlet temperature sensor 41 is a sensor that detects the temperature of the heat medium (heat medium inlet temperature) supplied to the regenerator 101 of the absorption chiller 21, and outputs a signal corresponding to the heat medium inlet temperature to the system controller 40. Output to.

  The heat medium outlet temperature sensor 42 is a sensor that detects the temperature of the heat medium flowing out from the regenerator 101 of the absorption refrigerator 21 (heat medium outlet temperature), and sends a signal corresponding to the heat medium outlet temperature to the system controller 40. Output.

  The cold water outlet temperature sensor 43 is a sensor that detects the temperature of the cold water (cold water outlet temperature) supplied from the absorption refrigerator 21 to the indoor unit 31, and outputs a signal corresponding to the cold water outlet temperature to the system controller 40.

  The cooling water outlet temperature sensor 44 is a sensor that detects the temperature of the cooling water that has flowed out of the cooling tower 25 (cooling water outlet temperature), and outputs a signal corresponding to the cooling water outlet temperature to the system controller 40.

  As one of the features of the present embodiment, when the system controller 40 determines the low-temperature state of the cooling water based on the preset determination temperature when the absorption chiller 21 is started up, Control is performed to limit the amount of heat input.

  Next, a control method of the absorption refrigeration system 1 according to the present embodiment will be described. FIG. 3 is a flowchart showing a control method of the absorption refrigeration system 1 according to the present embodiment. The process shown in this flowchart relates to the start-up operation of the absorption refrigeration machine 21 and is executed by the system controller 40 with the start of operation of the absorption refrigeration system 1 as a trigger.

  First, in step 1 (S1) to step 3 (S3), the system controller 40 operates the cold water pump 33, the heat medium pump 23, and the cooling water pump 27, respectively. Therefore, at this time, the operation of the solution pump 104b is not performed yet.

  In step 4 (S4), the system controller 40 determines whether or not the cooling water outlet temperature is equal to or higher than the first determination temperature T1 based on the detection signal of the cooling water outlet temperature sensor 44. This first determination temperature T1 is for determining whether or not the cooling water is so low that it is necessary to limit the supply of the heat medium to the regenerator 101, and an optimal value is set in advance through experiments and simulations. (For example, 15 ° C.). If the coolant outlet temperature is equal to or higher than the first determination temperature T1, an affirmative determination is made in step 4, and the process proceeds to step 5 (S5). On the other hand, if the coolant outlet temperature is lower than the first determination temperature T1, a negative determination is made in step 4, and the process proceeds to step 6 (S6).

  In step 5, the system controller 40 sets the heat medium three-way valve 24 to fully open. As a result, the heat medium from the heat exchanger 12 is supplied to the regenerator 101.

  On the other hand, in step 6, the system controller 40 determines whether the heat medium inlet temperature supplied to the regenerator 101 is equal to or higher than the second determination temperature T2 based on the detection signal of the heat medium inlet temperature sensor 41. . The second determination temperature T2 is a parameter for suppressing rapid heat input from the heat medium to the regenerator 101, and an optimum value is set in advance through experiments and simulations (for example, rated temperature −10 ° C. ( For example, 80 ° C.)). When the heat medium inlet temperature is equal to or higher than the second determination temperature T2, an affirmative determination is made in step 6, and the process proceeds to step 7 (S7). On the other hand, if the heat medium inlet temperature is lower than the second determination temperature T2, a negative determination is made in step 6, and the process proceeds to step 5.

  In step 7, the system controller 40 sets the opening degree of the heat medium three-way valve 24 to a limited state. For example, the opening degree is set to 30% to 50%. Thereby, supply of the heat medium to the regenerator 101 is restricted.

  In step 8 (S8), the system controller 40 determines whether the heat medium inlet temperature supplied to the regenerator 101 is equal to or higher than the third determination temperature T3 based on the detection signal of the heat medium inlet temperature sensor 41. To do. When the operation of the solution pump 104b is started, heat is input from the heat medium, and an extreme temperature drop of the heat medium may occur. The third determination temperature T3 is for determining whether the solution pump 104b can be operated, and an optimum value is set in advance through experiments and simulations (for example, 65 ° C.). When the heat medium inlet temperature is equal to or higher than the third determination temperature T3, an affirmative determination is made in step 8, and the process proceeds to step 9 (S9). On the other hand, if the heat medium inlet temperature is lower than the third determination temperature T3, a negative determination is made in step 8, and the process returns to step 8.

  In step 9, the system controller 40 operates the solution pump 104b.

  In step 10 (S10), the system controller 40 determines whether or not the cooling water outlet temperature is equal to or higher than the fourth determination temperature T4 based on the detection signal of the cooling water outlet temperature sensor 44. The fourth determination temperature T4 is used to determine whether or not the coolant outlet temperature has risen to a predetermined level through the operation from Step 1 to Step 9, and an optimum value is set in advance through experiments and simulations. (T1 <T4 (for example, 22 ° C.)). If the coolant outlet temperature is equal to or higher than the fourth determination temperature T4, an affirmative determination is made in step 10 and the process proceeds to step 11 (S11). On the other hand, if the coolant outlet temperature is lower than the fourth determination temperature T4, a negative determination is made in step 10, and the process proceeds to step 13 (S13).

  In step 11, the system controller 40 sets the cooling water three-way valve 28 to fully open. Thereby, the cooling water from the absorption refrigerator 21 is cooled in the heat exchange part 25b of the cooling tower 25. In step 12 (S12), the system controller 40 controls the solution bypass valve 29c1 in the automatic operation mode. This automatic operation mode is a control applied to the solution bypass valve 29c1 during normal operation of the absorption refrigerator 21. In this control, an optimum evaporator temperature that defines an optimum temperature state of the evaporator 103 is set through experiments and simulations (for example, optimum evaporator temperature = cold water outlet temperature−2 ° C.). The system controller 40 dynamically controls the opening degree of the solution bypass valve 29c1 so that the optimum evaporator temperature is reached.

  On the other hand, in step 13, the system controller 40 sets the cooling water three-way valve 28 to be fully closed. Thereby, the cooling water supplied from the absorption refrigeration machine 21 flows to the cooling water bypass passage 26c, and the cooling degree of the cooling water decreases (decrease in the cooling capacity of the cooling tower 25). In step 14 (S14), the system controller 40 controls the solution bypass valve 29c1 to open.

  In step 15 (S15), the system controller 40 determines whether or not the coolant outlet temperature is equal to or higher than the fifth determination temperature T5 based on the detection signal of the coolant outlet temperature sensor 44. The fifth determination temperature T5 is for determining whether or not the cooling water outlet temperature has increased to a predetermined level through the operation from step 1 to step 14, and an optimal value is set in advance through experiments and simulations. (T4 <T5 (for example, 28 ° C.)). If the coolant outlet temperature is equal to or higher than the fifth determination temperature T5, an affirmative determination is made in step 15 and the process proceeds to step 16 (S16). On the other hand, if the coolant outlet temperature is lower than the fifth determination temperature T5, a negative determination is made in step 15, and the process returns to step 15.

  In step 16, the system controller 40 operates the fan 25 a of the cooling tower 25.

  When these series of processes are completed, the system controller 40 ends the startup operation and shifts to the normal operation. In this starting operation, the temperature of the cooling water is at a low temperature (cooling water outlet temperature ≦ first determination temperature T1) and the temperature of the heat medium is within a certain temperature range with the rated temperature as the upper limit. In this case (heat medium inlet temperature ≧ rated temperature−10 ° C.), the heat medium three-way valve 24 is controlled so that the entire amount of the heat medium is not supplied to the regenerator 101. Thereby, since the regeneration capability of the regenerator 101 is reduced, rapid heat input from the heat medium to the regenerator 101 is suppressed.

  In order to suppress an extreme temperature drop of the heat medium, the solution pump 104b is not operated when the heat medium inlet temperature is equal to or lower than the third determination temperature T3. Thereby, since the regeneration capability of the regenerator 101 is reduced, rapid heat input from the heat medium to the regenerator 101 is suppressed.

  On the other hand, after the control for reducing the regeneration capability of the regenerator 101 is completed, the heat medium circulates, and the mixed solution of the absorption liquid and the refrigerant circulates in the solution flow path 29, so that heat input to the regenerator 101 is achieved. Is started. In this case, the cooling water three-way valve 28 is controlled, and the cooling water circulates around the heat exchange part 25b of the cooling tower 25. Thereby, radiation of the heat stored in the absorption chiller 21 by the cooling water is suppressed, and the temperature of the cooling water can be quickly raised.

  Moreover, in the condenser 102, since the input heat is radiated to the cooling water, the temperature of the cooling water can be quickly raised to a predetermined level. At this time, since the solution bypass valve 29c1 is opened, the amount of the concentrated solution passing through the heat transfer tube 104a of the absorber 104 is limited. Thereby, since the temperature fall of the evaporator 103 can be suppressed, freezing of a refrigerant | coolant can be prevented.

  When the temperature of the cooling water rises to some extent, the cooling water three-way valve 28 is fully opened, whereby the cooling water is supplied to the heat exchange unit 25b of the cooling tower 25. The solution bypass valve 29c1 is also switched to the normal automatic operation mode. In addition, when the temperature of the cooling water further rises, the fan 25a of the cooling tower 25 is operated. Thereby, it can transfer to a normal driving | operation.

  Thus, in the present embodiment, the absorption refrigeration system 1 is a system that supplies cooled cold water to the indoor unit 31 that is an external device that operates using cold water. The absorption refrigeration system 1 is supplied to an absorption chiller 21 that generates cold water by a circulation cycle of an evaporator 103, an absorber 104, a regenerator 101, and a condenser 102, and a regenerator 101 of the absorption chiller 21. A system that controls the absorption refrigeration system 1 and the cooling tower 25 that circulates cooling water between the engine 11 that is a heat source that heats the heating medium, the condenser 102 and the absorber 104 of the absorption refrigeration machine 21, and the like. And a controller 40. In this case, when the system controller 40 determines the low temperature state of the cooling water based on the preset first determination temperature T1, the system controller 40 performs control to reduce the regeneration capability of the regenerator 101.

  According to this configuration, since the amount of heat input to the regenerator 101 is limited by reducing the regenerative capacity of the regenerator 101, a situation in which a large amount of heat is taken from the heat medium to the absorption refrigerator 21 is suppressed. can do. As a result, a situation in which the temperature of the heat medium is remarkably lowered is suppressed, so that it is not necessary to stop the absorption refrigerator 21 until the temperature of the heat medium is recovered. As a result, the absorption refrigerator 21 can be smoothly started even at a cooling water temperature that cannot normally be started.

  Further, in the present embodiment, the control for reducing the regeneration capability of the regenerator 101 limits the amount of heat medium supplied to the regenerator 101 from the heat exchanger 12 that receives heat from the engine 11 and heats the heat medium. Is.

  According to this method, the regeneration capacity of the regenerator 101 can be reduced by limiting the amount of the heat medium supplied to the regenerator 101. Thereby, the amount of heat input to the regenerator 101 can be appropriately limited. As a result, the absorption refrigerator 21 can be smoothly started even at a cooling water temperature that cannot normally be started.

  The control for reducing the regeneration capability of the regenerator 101 is to stop the solution pump 104 b that circulates the solution between the regenerator 101 and the absorber 104.

  According to this method, since the circulation of the solution between the regenerator 101 and the absorber 104 is stopped, the regeneration capability of the regenerator 101 can be reduced. Thereby, the amount of heat input to the regenerator 101 can be appropriately limited. As a result, the absorption refrigerator 21 can be smoothly started even at a cooling water temperature that cannot normally be started.

  Further, in the present embodiment, the system controller 40 performs control to reduce the cooling water cooling amount by the cooling tower 25 after finishing the control for reducing the regeneration capability of the regenerator 101.

  According to this structure, since it can suppress that the heat input into the absorption refrigerator 21 is dissipated to cooling water, it can lead to the rise of the temperature of a solution. As a result, the start-up can be performed smoothly, the start-up time can be shortened, and temperature fluctuations toward the engine 11 can be suppressed.

  In the present embodiment, the system controller 40 limits the solution flowing into the absorber 104 after completing the control for reducing the regeneration capability of the regenerator 101. Specifically, the solution bypass valve 29c1 is opened.

  According to this configuration, since the temperature drop of the evaporator 103 is suppressed, the temperature of the solution can be increased. Thereby, crystallization of the solution can be avoided. Moreover, since the temperature drop of the evaporator 103 is suppressed, freezing of the refrigerant can be avoided. As a result, it is possible to solve the problem that the absorption refrigerator 21 cannot be started due to crystallization of the solution or freezing of the refrigerant. As a result, the start-up can be performed smoothly, so that the start-up time can be shortened, and temperature fluctuations toward the engine 11 can be suppressed.

  As described above, the present invention has been described based on the embodiment, but the present invention is not limited to the above embodiment, and may be modified without departing from the gist of the present invention.

  In the present embodiment, the engine is exemplified as the heat source, but various types can be used as long as the heat source is used. For example, the heat source may be a fuel cell.

1 Absorption Refrigeration System 10 First System 11 Engine (Heat Source)
DESCRIPTION OF SYMBOLS 12 Heat exchanger 20 2nd system 21 Absorption type refrigerator 101 Regenerator 102 Condenser 103 Evaporator 104 Absorber 25 Cooling tower 30 3rd system 31 Indoor unit 40 System controller (controller)

Claims (5)

In an absorption refrigeration system that supplies a cooled refrigerant to an external device that operates using the refrigerant,
An absorption refrigerator that cools the refrigerant by a circulation cycle by an evaporator, an absorber, a regenerator, and a condenser;
A heat source for heating a heat medium supplied to the regenerator of the absorption refrigerator,
A cooling tower for circulating cooling water between the condenser and the absorber of the absorption refrigerator,
A controller for controlling the absorption refrigeration system,
The absorption refrigeration system, wherein when the controller determines a low temperature state of the cooling water based on a preset determination temperature, the controller performs control to reduce the regeneration capability of the regenerator.   2. The absorption refrigeration system according to claim 1, wherein the control for reducing the regeneration capability of the regenerator limits the amount of heat medium supplied from the heat source to the regenerator.   The control for reducing the regeneration capability of the regenerator stops a solution pump that circulates a solution containing an absorbing liquid and a refrigerant between the regenerator and the absorber. Absorption refrigeration system described in 1.   The said controller performs control which decreases the cooling amount of the cooling water by the said cooling tower, after complete | finishing the control which reduces the reproduction | regeneration capability of the said regenerator. Absorption refrigeration system.   5. The controller according to claim 1, wherein after the control for reducing the regeneration capability of the regenerator is completed, the controller performs control for increasing the temperature of the solution containing the absorbing liquid and the refrigerant. The absorption refrigeration system described.

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