JP2008106983A - Absorption type heat pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorption type heat pump shortening a build-up time from the start to steady operation by securing the amount of solution flowing into an absorber 11 and a regenerator 1 from the start when there is no pressure difference between the absorber 11 and the regenerator 1. <P>SOLUTION: A second solution circulating pump 23 is disposed to receive the inflow of a dilute solution obtained after a dilute solution from the absorber 11 exchanges heat with a concentrated solution from the regenerator 1 in a solution heat exchanger 22, and the rotating speed of the second solution circulating pump 23 is controlled by the pressure difference between the absorber 11 and the regenerator 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an absorption heat pump that takes out a medium having a temperature higher than a heat source temperature, and more particularly to a solution circulation configuration.

  In general, this type of absorption heat pump supplies heat source medium to the evaporator and regenerator, and takes out the heated source medium at a temperature higher than the heat source temperature from the absorber, so that the pressure of the evaporator and absorber is high during steady operation. Since the pressure in the condenser and the condenser is low, the solution is circulated from the absorber to the regenerator by the pressure difference between the absorber and the regenerator. However, since there is no pressure difference between the absorber and the regenerator at start-up, a means for circulating the solution from the absorber to the regenerator is required. For example, in Patent Document 1, the solution is circulated from the absorber to the regenerator by the position head by installing the absorber at a position higher than the regenerator. Moreover, in patent document 2, while arrange | positioning an absorber to a position higher than a regenerator like patent document 1, it enables the solution from an absorber to circulate to a regenerator by bypassing a solution heat exchanger at the time of starting, A part of the solution discharged from the solution circulation pump for circulating the solution from the regenerator to the absorber is recirculated to the regenerator through the bypass pipe.

  In the case of Patent Document 1, since the solution is circulated only by the position head of the absorber and the regenerator at the start-up, the amount of solution circulation is small, and it takes time to concentrate the solution in the regenerator. It takes time until the refrigerant is introduced and sprayed by the evaporator. Moreover, since it is necessary to make the solution of an absorber into the height position which can circulate a solution to a regenerator with a position head, it will become an absorption type heat pump with a high height and few freedom in apparatus arrangement | positioning. Also, this type of absorption heat pump generally improves the performance of the absorber when the spraying density is increased. In addition, the amount of solution circulated during steady operation is controlled so that the amount of solution equivalent to the amount of solution flowing from the absorber to the regenerator flows from the regenerator to the absorber due to the pressure difference between the absorber and the regenerator. Therefore, there is a limit to the spray density in the absorber. That is, with the configuration of Patent Document 1, it may not be possible to achieve a spray density that can sufficiently exhibit the performance of the absorber.

  In the case of Patent Document 2, since a part of the solution circulating from the regenerator to the absorber is recirculated to the regenerator at the time of startup, the amount of spraying in the absorber is reduced. That is, until the refrigerant starts to be sprayed in the evaporator, the heated medium to be taken out from the absorber is heated to the solution sprayed in the absorber, but the sprayed amount of the absorber is reduced. Therefore, the heating source medium taken out from the absorber is not sufficiently heated. Also, until the temperature detected by the evaporator or absorber reaches the set value, the total amount of solution from the regenerator is not sprayed to the absorber through the solution heat exchanger, and the total amount of solution from the absorber is Since it is not led to the regenerator through the heat exchanger, heat recovery in the solution heat exchanger becomes insufficient, and it takes time to raise the temperature of the solution serving as a heating source of the heated source medium taken out from the absorber. Become. Moreover, since it is set as the structure which arrange | positions an absorber in the position higher than a regenerator like patent document 1, it will become tall.

  Further, unlike this type of absorption heat pump, the absorption chiller / heater of Patent Document 3 that takes out chilled / hot water from the evaporator has a solution circulation pump for circulating the solution from the absorber to the high-temperature regenerator at the outlet of the absorber. Between the absorber and the low-temperature heat exchanger. Specifically, the solution having the same temperature as the outlet of the absorber is configured to flow into the solution circulation pump. In the case of the absorption chiller / heater of Patent Document 3, the cooling operation is performed so that cold water of about 7 to 10 ° C. is taken out from the evaporator, and in the heating operation, hot water of about 50 to 60 ° C. is taken out of the evaporator. At this time, the solution temperature at the outlet of the absorber is about 40 to 45 ° C. in the cooling operation and about 80 to 90 ° C. in the heating operation. That is, in the configuration of Patent Document 3, the temperature of the solution flowing into the solution circulation pump at the absorber outlet is highest at about 80 to 90 ° C. during the heating operation. On the other hand, in this type of absorption heat pump that is the subject of the present invention, for example, when a heated source medium of about 130 ° C. is taken out from the absorber, the solution temperature at the absorber outlet is about 125 ° C., The temperature is considerably higher than the solution temperature at the absorber outlet during heating operation in the absorption chiller / heater of Patent Document 3.

JP 58-69372 A (page 4, FIG. 2) Japanese Patent Laid-Open No. 60-200062 (page 5, figure) JP-A-10-170091 (page 6, FIG. 1)

  In the above prior art, the amount of solution circulation from the absorber to the regenerator and the amount of solution circulation from the regenerator to the absorber are between the start-up and the pressure difference between the absorber and the regenerator during steady operation. Since the operation is performed in a state smaller than that in the steady operation, the amount of heat that can be recovered by the solution heat exchanger is reduced, and it takes time to raise the temperature of the solution sprayed to the absorber. As a result, it takes time to start up from startup to steady operation. Moreover, since it is necessary to arrange | position an absorber and a regenerator up and down, it is tall and has little freedom in apparatus arrangement.

  Further, as a method for improving the performance of this type of absorption heat pump, an increase in the spraying density of the absorber can be mentioned. As means for this, there are methods of increasing the amount of solution circulation, recirculating the solution in the absorber, or making the longitudinal section of the tube group cross section of the absorber. According to the configurations of Patent Document 1 and Patent Document 2, from the regenerator, the pressure difference between the absorber and the regenerator and the amount of solution circulation from the absorber to the regenerator that flows only by the height difference between the absorber and the regenerator. The amount of solution circulation to the absorber is determined. Among these, since the pressure difference between the absorber and the regenerator is determined by the operating conditions of the heat pump cycle, it is necessary to increase the position of the absorber in Patent Document 1 and Patent Document 2 when attempting to increase the solution circulation amount. As a result, the entire device becomes larger. Regarding the recirculation of the solution, it becomes necessary to newly add a pump and piping for recirculation, and the apparatus becomes complicated. Furthermore, the method of making the absorber tube group vertically long also leads to an increase in the size of the device. Therefore, with these configurations, it is difficult to improve the performance of the absorber by increasing the spray density under realistic equipment dimensions.

  Further, in this type of absorption heat pump, the solution temperature at the absorber outlet is about 125 ° C., so that, for example, in a solution circulation pump that has been installed in the absorption chiller / heater of Patent Document 3, the allowable temperature Because it exceeds, it cannot be supported. If the solution circulation pump tries to cope with a solution having a high temperature of about 125 ° C., it is necessary to review the specifications of the motor insulation class and seal material, etc., which increases the cost and increases the durability. The problem remains.

  This type of absorption heat pump is often used industrially by taking out a high-temperature / high-pressure heated source medium, and it is necessary to ensure safety against an excessive increase in the temperature and pressure of the heated source medium. However, there are no above-mentioned prior arts that take this into account.

  The present invention is made to solve the above problems, and the object of the present invention is to recycle the solution from the absorber to the regenerator without depending on the pressure difference between the absorber and the regenerator from the start. And providing an absorption heat pump that can quickly increase the temperature of the solution sprayed on the absorber to quickly start up from start-up to steady operation and secure the degree of freedom of equipment placement. .

  Furthermore, it is providing the absorption heat pump which can make the solution temperature which flows in into a solution circulation pump the same as the solution temperature of the absorber exit at the time of the heating operation of patent document 3. FIG.

  It is another object of the present invention to provide an absorption heat pump that can ensure sufficient safety so that the temperature or pressure of the heated source medium taken out from the absorber does not increase excessively.

  In order to achieve the above object, in the present invention, a regenerator, a condenser, an evaporator, an absorber, a solution heat exchanger, a refrigerant spray pump, a refrigerant circulation pump, and a solution for circulating a solution from the regenerator to the absorber. A solution / refrigerant circulation circuit is configured by connecting the first solution circulation pump with a solution pipe and a refrigerant pipe, and a heat source medium is introduced into the regenerator and the evaporator, and cooling water is passed through the condenser for absorption. In the absorption heat pump that takes out the heated source medium above the heat source temperature from the regenerator, the second solution circulation pump is connected to the second solution circulation pump. The dilute solution after heat exchange with the concentrated solution is arranged to flow in.

  Also, a first pressure sensor for detecting the pressure in the vessel provided in one of the regenerator and the condenser, and a second pressure sensor for detecting the inside of the vessel provided in one of the absorber and the evaporator. A control device is provided that can control the rotation speed of the second solution circulation pump according to the pressure difference. When the pressure difference increases, the control device decreases the rotation speed of the second solution circulation pump, and when the pressure difference decreases. Control is performed to increase the rotation speed of the second solution circulation pump.

  Further, the control device increases the rotation speed of the first solution circulation pump when the pressure difference between the first pressure sensor and the second pressure sensor increases, and decreases the rotation speed of the first solution circulation pump when the pressure difference decreases. Is controlling.

  According to the present invention, while the refrigerant that can be sprayed by the evaporator at the time of start-up is produced, the second solution circulation pump allows the second solution circulation pump to start the absorber and the regenerator without depending on the pressure difference between the absorber and the regenerator. Therefore, the temperature of the solution sprayed to the absorber can be sufficiently increased, and the start-up to the steady operation can be performed quickly.

  Furthermore, since the solution can be circulated from the absorber to the regenerator without depending on the pressure difference between the absorber and the regenerator, it can be configured without arranging the absorber and the regenerator up and down, and the equipment can be arranged freely. The degree can be increased.

  In addition, the second solution circulation pump is arranged to circulate the solution after heat exchange with the solution heat exchanger, so the solution circulation pump with the same specifications as the absorption chiller / heater can be used, It is possible to eliminate a decrease in durability and an increase in cost.

  In addition, since the first solution circulation pump and the second solution circulation pump are appropriately controlled by the pressure difference between the absorber and the regenerator, the rotation speed of each of them is particularly controlled. It is possible to provide an absorption heat pump that can reduce power consumption.

  Furthermore, when the temperature of the heated source medium taken out from the absorber exceeds the set value, the rotation speed of the refrigerant spray pump of the evaporator is decreased, so that the amount of refrigerant vapor generated in the evaporator is reduced. Because it can be operated to reduce the amount of heat absorbed by the absorption of refrigerant vapor in the absorber and lower the temperature of the heated source medium, it is possible to prevent abnormal temperature and pressure rises and to ensure sufficient safety. An absorption heat pump that can be secured can be provided.

  First, the best example 1 for carrying out the present invention will be described.

  FIG. 1 shows an embodiment of the present invention. A broken line in FIG. 1 indicates a signal line that connects each element to be described later and the control device 48. In the apparatus of this embodiment, water is used as the refrigerant, and an aqueous lithium bromide solution is used as the solution (absorbent).

  First, the structure of the absorption heat pump of the present invention and the operation of the refrigerant and solution side during steady operation will be described. In the regenerator 1, a dilute solution having a low concentration is introduced from the absorber 11 through the pipe 25 through the second solution circulation pump 23 to the spraying device 3 and sprayed to the heat exchange unit 2. The sprayed diluted solution is heated and concentrated by the heat source medium in the heat exchanging unit 2 to become a concentrated solution having a high concentration with the refrigerant vapor, and the concentrated solution is temporarily stored in the lower part of the regenerator 1. The refrigerant vapor separated from the concentrated solution is guided to the condenser 6 through the baffle 10 for preventing the concentrated solution from being misted. The refrigerant vapor guided to the condenser 6 exchanges heat with the cooling water flowing through the heat exchange unit 7 to be condensed and liquefied, and is temporarily stored in the lower part of the condenser 6. The refrigerant stored in the lower portion of the condenser 6 is adjusted in flow rate by the refrigerant float valve 9 by the refrigerant circulation pump 8, led to the evaporator 14 through the pipe 26. At this time, the refrigerant float valve 9 is controlled so that the opening degree increases when the liquid level rises, and the opening degree decreases when the liquid level drops. The refrigerant guided to the evaporator 14 is guided to the spraying device 15 through the pipe 20 by the coolant spraying pump 17, and the coolant is sprayed from the spraying device 15 to the heat exchange unit 16. The sprayed refrigerant exchanges heat with the heat source medium flowing in the heat exchanging section 16 to evaporate into refrigerant vapor, and is guided to the absorber 11 through the eliminator 21 for preventing mist up. The refrigerant that could not be evaporated by the evaporator 14 is again guided to the spraying device 15 through the pipe 20 by the coolant spraying pump 17.

  On the other hand, the concentrated solution stored in the lower part of the regenerator 1 is adjusted in flow rate by the solution float valve 5 by the first solution circulation pump 4, passed through the solution heat exchanger 22, and guided to the spraying device 12 of the absorber 11. At this time, the solution float valve 5 is controlled so that the opening degree increases when the liquid level rises and decreases when the liquid level drops. The concentrated solution guided to the spraying device 12 is sprayed to the heat exchange unit 13. The sprayed concentrated solution absorbs the refrigerant vapor flowing from the eliminator 21 and heats the heated source medium flowing in the heat exchanging unit 13 with the absorbed heat generated at this time. The diluted solution that has absorbed and thinned the refrigerant vapor passes through the solution heat exchanger 22 through the pipe 25, where it exchanges heat with the concentrated solution concentrated in the regenerator 1, and the second solution circulation pump 23 causes the regenerator 1. Guided to the spraying device 3. As described above, the refrigerant and the solution operate.

  The regenerator 1 is provided with a liquid level switch (not shown). This liquid level switch is connected to the control device 48. In order to prevent cavitation of the first solution circulation pump 4, the control device 48 performs control so that the first solution circulation pump 4 is not operated when the liquid level switch does not sense the liquid level. Similarly to the regenerator 1, a liquid level switch (not shown) is installed in the condenser 6, the absorber 11, and the evaporator 14, and these are connected to the control device 48. The control devices 48 control the refrigerant 6 so that the refrigerant circulation pump 8 is not operated in the condenser 6, the second solution circulation pump 23 is used in the absorber 11, and the refrigerant spray pump 17 is not operated in the evaporator 14 unless each of them senses the liquid level. To do.

In this embodiment, the absorber 11 has a second pressure sensor (P2) 44 for detecting the pressure inside the container, and the regenerator 1 has a first pressure sensor (for detecting the pressure inside the container). P1) 45 is installed. The output of each pressure sensor is connected to the control device 48. The control device 48 calculates a pressure difference between the first pressure sensor (P1) 45 and the second pressure sensor (P2) 44, and rotates the first solution circulation pump 4 and the second solution circulation pump 23 based on the calculation result. Control the number. The first pressure sensor 45 is not limited to being provided in the regenerator 1 and may be provided in the condenser 6 provided in the same container. Similarly, the second pressure sensor 44 is not limited to being provided in the absorber 11 but may be provided in the evaporator 14 accommodated in the same container.

Further, the absorber 11 is provided with a liquid level detector 27 for detecting the liquid level of the solution stored in the lower part of the absorber 11. The signal line of the liquid level detector 27 is connected to the control device 48. When the control device 48 detects that the liquid level detector 27 has fallen below a preset liquid level, the rotation of the second solution circulation pump 23 determined from the pressure difference between the first pressure sensor 45 and the second pressure sensor 44. The number of revolutions of the second solution circulation pump 23 is controlled to gradually decrease until the liquid level is restored to the set value. When the liquid level exceeds the set value, control is performed so that the second solution circulation pump 23 is operated at the number of rotations determined again from the pressure difference between the first pressure sensor 45 and the second pressure sensor 44. At the solution outlet portion of the absorber 11, when the liquid level becomes low, a vortex is generated at the solution outlet portion, and it becomes easy to entrain the refrigerant vapor. Therefore, the entrained refrigerant vapor amount is used for heating the heated source medium taken out from the absorber 11. It does not contribute to heat loss. Accordingly, the liquid level detector 27 of the absorber 11 always has a liquid level height higher than a preset level in order to prevent the refrigerant vapor from being entrained from the evaporator 14 at the solution outlet of the absorber 11. It is installed to control.

  Next, the operation of the cooling water will be described. A pipe 43 is connected so that the cooling water circulates between the cooling tower (not shown) and the heat exchange section 7 of the condenser 6. Then, the cooling water whose temperature is adjusted by the cooling tower is supplied to the heat exchange unit 7.

  Next, operations on the heat source medium side and the heated source medium side will be described. As the heat source medium, hot water or steam generated in a factory or the like is supplied through a pipe 37 as a drive source of an absorption heat pump. The pipe 37 is branched in the middle, and a part of the heat source medium is supplied to the heat exchange unit 2 of the regenerator 1 and the rest is supplied to the heat exchange unit 16 of the evaporator 14. The supplied heat source medium exchanges heat with the dilute solution in the heat exchange unit 2 of the regenerator 1 and exchanges heat with the refrigerant in the heat exchange unit 16 of the evaporator 14. The heat source medium that has exited the heat exchange unit 2 of the regenerator 1 passes through the flow rate adjustment valve 40, exits the heat exchange unit 16 of the evaporator 14, joins the heat source medium that has passed through the flow rate adjustment valve 41, and flows out through the pipe 38. . Further, a three-way valve 39 is provided in the pipe 38 exiting from the heat exchanging section 16 of the evaporator 14, and the heat source medium introduced from the pipe 37 can be bypassed by the three-way valve 39. The signal line of the three-way valve 39 is connected to the control device 48.

On the other hand, the heated source medium side is separated into steam and hot water by a flash tank 30 which is a gas-liquid separation means. The vapor | steam isolate | separated here is pressure-controlled with the pressure-reduction valve 33, and is guide | induced to the user side with the piping 32. FIG. On the other hand, the hot water flows into the heat exchange unit 13 of the absorber 11 by the hot water pump 31 through the pipe 28. The hot water that has flowed into the heat exchanging unit 13 is heated by the absorption heat generated when the concentrated solution sprayed on the heat exchanging unit 13 absorbs the refrigerant vapor, and flows again into the flash tank 30 through the pipe 29. The flash tank 30 is provided with a third pressure sensor (P3) 47 for detecting the pressure in the flash tank 30 and a liquid level detector 36 for detecting the level of warm water accumulated in the lower part of the flash tank 30. Has been. The third pressure sensor P3 and the signal line of the liquid level detector 36 are connected to the control device 48. In addition, a pipe 34 for connecting the flash tank 30 and the hot water pump 31 is provided with a pipe 34 for supplying hot water corresponding to the amount of steam guided to the user side through the pipe 32 via a flow rate adjusting valve 35 and is controlled. Connected to device 48. A temperature sensor (T) 46 for detecting the temperature of the hot water heated by the heat exchange unit 13 is installed in the pipe 29 connecting the heat exchange unit 13 and the flash tank 30 of the absorber 11. . The signal line of the temperature sensor 46 is connected to the control device 48.

  Here, when the pressure in the flash tank 30 detected by the third pressure sensor 47 exceeds a preset set value, the opening degree on the bypass side of the three-way valve 39 is increased by the control device 48. Thereby, a part of the heat source medium supplied by the pipe 37 is bypassed to the pipe 38, and the flow rate of the heat source medium supplied to the heat exchange unit 2 of the regenerator 1 and the heat exchange unit 16 of the evaporator 14 is reduced. By reducing the flow rate of the heat source medium, the heat exchanging unit 13 of the absorber 11 is controlled to reduce the amount of heating to the heated source medium and to reduce the pressure in the flash tank 30. Conversely, when the pressure in the flash tank 30 detected by the third pressure sensor 47 falls below a preset value, the controller 48 reduces the opening on the bypass side of the three-way valve 39. This reduces the amount of heat source medium that bypasses the pipe 37 to the pipe 38. By reducing the amount of the heat source medium, the flow rate of the heat source medium supplied to the heat exchange unit 2 of the regenerator 1 and the heat exchange unit 16 of the evaporator 14 is increased. Thus, the heat exchange unit 13 of the absorber 11 is controlled so as to increase the amount of heating to the heated source medium and increase the pressure in the flash tank 30.

In addition, when the temperature of the hot water heated by the heat exchanging unit 13 of the absorber 11 detected by the temperature sensor 46 reaches a temperature exceeding the preset first set value, the control device 48 sets the hot water pump 31. It is controlled to increase the circulation rate of hot water by increasing the number of revolutions. Thereby, the temperature detected by the temperature sensor 46 can be lowered. When the temperature detected by the temperature sensor 46 is lower than the first set value, the control device 48 performs control so as to decrease the number of circulations of the hot water by decreasing the rotation speed of the hot water pump 31. Thereby, the temperature detected by the temperature sensor 46 can be raised.

  Next, the relationship between the temperature sensor 46 and the control device 48 according to the present invention will be described. When the temperature detected by the temperature sensor 46 exceeds a preset second set value, the control device 48 reduces the amount of refrigerant generated in the evaporator 14 and decreases the amount of heat absorbed in the absorber 11. That is, the control device 48 performs control so as to decrease the rotational speed of the refrigerant spray pump 17 until the temperature detected by the temperature sensor 46 becomes lower than the second set value. The temperature set based on the temperature detected by the temperature sensor 46 is a second set value for controlling the rotational speed of the refrigerant spray pump 17 from the first set value for controlling the rotational speed of the hot water pump 31. Set higher for. The first set value is set so that the steam temperature desired to be taken out from the pipe 32 during steady operation is obtained, and the second set value is set higher than the first set value in order to prevent an abnormal temperature rise. Thus, by controlling the number of rotations of the three-way valve 39 with the detection value of the third pressure sensor 47 and the temperature of the hot water pump 31 and the refrigerant spray pump 17 with the detection value of the temperature sensor 46, the amount of steam on the user side, Even when the temperature at which the heat source medium flows or the temperature at which the cooling water flows changes, the absorption heat pump can be stably operated.

  Further, the liquid level height in the flash tank 30 detected by the liquid level detector 36 is controlled so as to be kept substantially constant regardless of the amount of steam guided from the pipe 32 to the user side. That is, the control device 48 adjusts the amount of hot water to be supplied to the pipe 34 by controlling the opening degree of the flow rate adjustment valve 35.

  During steady operation, the absorption heat pump according to the present invention shown in FIG. 1 operates and operates as described above. In the operation of the absorption heat pump, the temperature of the heated medium taken out from the absorber 11 is determined by the heat source temperature and cooling water temperature conditions that can be supplied to the absorption heat pump, and the heat source medium and cooling water flow rate conditions. For example, if the heat source medium is 90 ° C. warm water and the cooling water is 32 ° C., steam of about 130 ° C. can be taken out from the pipe 32 depending on the flow conditions of the hot water and the cooling water.

  Next, the operation and effect from the start to the steady operation according to the present invention will be described with reference to FIGS. In the absorption heat pump of the present invention, the second solution circulation pump 23 is installed between the solution heat exchanger 22 and the regenerator 1 in the pipe 25 connecting the absorber 11 to the regenerator 1. The second solution circulation pump 23 is controlled by the control device 48 from the pressure difference between the pressure in the regenerator 1 detected by the first pressure sensor 45 and the pressure in the absorber 11 detected by the second pressure sensor 44. The rotational speed of the second solution circulation pump 23 is determined. For example, the control is performed as shown by the solid line in FIG.

  As shown in FIG. 2, when there is no pressure difference ΔP, the rotational speed S of the second solution circulation pump 23 becomes the highest, and the rotational speed S of the second solution circulation pump 23 decreases as the pressure difference ΔP increases. Be controlled. Further, the first solution circulation pump 4 is controlled by the control device 48 between the pressure in the regenerator 1 detected by the first pressure sensor 45 and the pressure in the absorber 11 detected by the second pressure sensor 44. From the difference, the rotational speed of the first solution circulation pump 4 is determined. For example, as shown by the broken line in FIG. 2, the rotation speed S of the first solution circulation pump 4 when there is no pressure difference ΔP is the lowest, the pressure difference ΔP is increased, and the rotation speed S of the first solution circulation pump 4 is Controlled to go up. Here, the rotation speed S of the first solution circulation pump 4 is such that the amount of solution approximately equal to the amount of solution circulated from the absorber 11 to the regenerator 1 is the same as the amount of solution circulated from the regenerator 1 to the absorber 11 by the first solution circulation pump. The rotation speed S is set so as to be circulated in the range.

  Thereby, even if there is no pressure difference (DELTA) P of the absorber 11 and the regenerator 1 at the time of starting, it can ensure arbitrary solution circulation amount simultaneously with starting. That is, a sufficient amount of solution can be sprayed by the regenerator 1 and the absorber 11 simultaneously with the start-up. For this reason, from the start-up, the regenerator 1 can perform heat exchange between the heat source medium and a sufficient amount of dilute solution, and can be separated into refrigerant vapor and concentrated solution. In addition, since the refrigerant condensed and liquefied by the condenser 6 can be quickly guided to the evaporator 14, it is possible to shorten the time from the start-up until the refrigerant can be dispersed in the evaporator 14. That is, it is possible to contribute to shortening of the start-up from startup to steady operation.

  In addition, the temperature of the dilute solution in the regenerator 1 is increased by exchanging heat with the heat source medium during the period from the start until the refrigerant is sprayed on the evaporator 14. Since the concentrated solution whose temperature has risen is sprayed on the absorber 11, the heated source medium flowing in the heat exchanging section 13 can be heated. Further, the pressure difference ΔP between the absorber 11 and the regenerator 1 is always circulated from the absorber 11 to the regenerator 1 via the solution heat exchanger 22 until the pressure difference ΔP in the steady operation from the start-up. Since a concentrated solution amount substantially equal to the diluted solution amount can be circulated from the regenerator 1 to the absorber 11 via the solution heat exchanger 22, heat recovery can be performed efficiently. That is, the diluted solution that has become a high temperature by absorbing the refrigerant vapor by the absorber 11 can be used for heating the concentrated solution that is sprayed to the absorber 11 via the solution heat exchanger 22. Thereby, the temperature rise of the concentrated solution spread | diffused to the absorber 11 can be performed rapidly, and it can contribute to the shortening of the start-up from starting to a steady operation.

  Furthermore, since the second solution circulation pump 23 is installed, the solution can be circulated from the start-up when there is no pressure difference ΔP between the absorber 11 and the regenerator 1, so the absorber 11 needs to be positioned higher than the regenerator 1. Disappears. Therefore, when designing the absorption heat pump according to the present invention, the degree of freedom of equipment arrangement increases, which can contribute to downsizing of the absorption heat pump.

  Further, the first solution circulation pump 4 and the second solution circulation pump 23 are appropriately controlled by the control device 48 as shown in FIG. 2 from the pressure difference ΔP between the absorber 11 and the regenerator 1. Since it did in this way, it can contribute to reduction in the power consumption at the time of starting especially at the time of a pressure difference fluctuate | varied.

Further, since the second solution circulation pump 23 is installed between the solution heat exchanger 22 and the regenerator 1, the diluted solution that has absorbed the refrigerant vapor at the absorber 11 and has reached a high temperature becomes a solution heat. The dilute solution after heat exchange with the low temperature concentrated solution circulated from the regenerator 1 to the absorber 11 by the exchanger 22 can be caused to flow into the second solution circulation pump 23. Here, for example, when the heat source medium is 90 ° C. exhausted hot water, the cooling water is 32 ° C., and the flow rate conditions of the hot water and the cooling water are adjusted to take out steam at about 130 ° C. from the pipe 32, the absorber 11. Since the solution temperature at the outlet is about 125 ° C., and the regenerator 1 is heated with the waste water at 90 ° C., the temperature of the concentrated solution at the outlet of the regenerator 1 is about 83 ° C. depending on the flow rate of the waste water. It becomes. At this time, in the solution heat exchanger 22, a dilute solution having an inlet temperature of 125 ° C and a concentrated solution having a temperature of 83 ° C exchange heat. Here, if the temperature efficiency on the side circulating from the absorber 11 to the regenerator 1 of the solution heat exchanger 22 is 0.85, the outlet temperature of the solution heat exchanger 22 is 89.3 ° C., and at this temperature, the second temperature The solution can be introduced into the solution circulation pump 23. That is, the present invention is compared with about 70 to 90 ° C. in the heating operation in which the inflow temperature to the solution circulation pump of an absorption chiller / heater (not shown) that takes chilled / hot water from a general evaporator is highest. In the structure which concerns on this, the inflow temperature of the solution to the 2nd solution circulation pump 23 can be made into the temperature condition range used with a general absorption-type cold water heater. Thereby, in the absorption heat pump of this invention, the solution circulation pump of a general absorption-type cold / hot water machine can be used for the 2nd solution circulation pump 23. FIG. If the second solution circulation pump 23 is installed between the absorber 11 and the solution heat exchanger 22 in the same manner as in a general absorption chiller / heater in the absorption heat pump of the present invention, the second solution Since the solution inflow temperature to the circulation pump 23 is 125 ° C., it is impossible to use a solution circulation pump that has been used in a general absorption chiller / heater and has been proven to be durable. It is necessary to change the specifications of the class and the seal material, resulting in an increase in cost.

  In the absorption heat pump shown in FIG. 1 of the present invention, the solution float valve 5 is provided on the discharge side of the first solution circulation pump 4, but the cycle can be established without the solution float valve 5. However, when the solution float valve 5 is installed on the discharge side of the first solution circulation pump 4 as shown in FIG. 1, the liquid level in the regenerator 1 is directly detected so that the liquid level becomes constant. Since the opening of the solution float valve 5 is adjusted according to the liquid level, the liquid level in the regenerator 1 can be more reliably made constant if the solution float valve 5 is installed. Thus, the liquid level in the absorber 11 can also be made constant.

  In FIG. 2, the first solution circulation pump 4 and the second solution circulation pump 23 are configured so that the rotation speed S changes stepwise with respect to the pressure difference ΔP between the absorber 11 and the regenerator 1. . However, the present invention is not limited to this as long as a sufficient amount of solution to be spread on the absorber 11 and the regenerator 1 can be secured even if the pressure difference ΔP changes. For example, the rotation speed S of the first solution circulation pump 4 and the second solution circulation pump 23 may be controlled so as to continuously change with respect to the pressure difference ΔP. You may control combining.

It is a figure which shows the cycle flow of the absorption heat pump which concerns on embodiment of this invention. It is a figure which shows the control method of the 1st solution circulation pump 4 and the 2nd solution circulation pump 23 of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Regenerator 2,7,13,16 Heat exchange part 3,12,15 Spreading device 4 1st solution circulation pump 5 Solution float valve 6 Condenser 8 Refrigerant circulation pump 9 Refrigerant float valve 10 Baffle 11 Absorber 14 Evaporator 17 Refrigerant spray pump 18, 20, 24, 25, 26, 28, 29, 32, 34, 37, 38, 43 Pipe 19 Refrigerant blow valve 21 Eliminator 22 Solution heat exchanger 23 Second solution circulation pump 27, 36 Liquid level detection 30 Flash tank 31 Hot water pump 33 Pressure reducing valve 35, 40, 41 Flow rate adjusting valve 39 Three-way valve 48 Control device

Claims (6)

Regenerator, condenser, evaporator, absorber, solution heat exchanger, refrigerant spray pump, refrigerant circulation pump, and first solution circulation pump for circulating the solution from the regenerator to the absorber are connected by solution piping and refrigerant piping. Then, the solution / refrigerant circulation circuit is configured, the heat source medium is put into the regenerator and the evaporator, the cooling water is passed through the condenser, and the heat source medium above the heat source temperature is taken out from the absorber. In the type heat pump,
A second solution circulation pump for circulating a dilute dilute solution from the absorber to the regenerator is provided, and the second solution circulation pump is disposed between the solution heat exchanger and the regenerator. Absorption heat pump.   A first pressure sensor for detecting the pressure in the vessel provided in one of the regenerator and the condenser, and a second for detecting the pressure in the vessel provided in one of the absorber and the evaporator A control device is provided for controlling the rotation speed of the second solution circulation pump according to the pressure difference with the pressure sensor, and the control device decreases the rotation speed of the second solution circulation pump when the pressure difference increases, thereby reducing the pressure difference. The absorption heat pump according to claim 1, wherein the absorption heat pump is controlled to increase the rotational speed of the second solution circulation pump.   A first pressure sensor for detecting the pressure in the vessel provided in one of the regenerator and the condenser, and a second for detecting the pressure in the vessel provided in one of the absorber and the evaporator A control device is provided for controlling the rotation speed of the first solution circulation pump according to the pressure difference with the pressure sensor. When the pressure difference increases, the control device decreases the rotation speed of the first solution circulation pump and reduces the pressure difference. The absorption heat pump according to claim 1 or 2, wherein the first solution circulation pump is controlled to increase the rotational speed. A regenerator, a condenser, an evaporator, an absorber, a solution heat exchanger, a refrigerant spray pump, and a refrigerant circulation pump, and the first solution circulation pump for circulating the solution from the regenerator to the absorber is a solution pipe And a refrigerant pipe connected to form a solution / refrigerant circulation circuit, a heat source medium is introduced into the regenerator and the evaporator, cooling water is passed through the forward inclined condenser, and a heat source is supplied from the absorber. In the absorption heat pump that takes out the heated source medium above the temperature,
The refrigerant for providing a temperature sensor for detecting the temperature of the heated source medium taken out from the absorber, and for dispersing the refrigerant to the evaporator when the temperature detected by the temperature sensor exceeds a preset value An absorption heat pump, characterized in that a control device is provided for controlling the rotation speed of the spray pump to decrease. A regenerator, a condenser, an evaporator, an absorber, a solution heat exchanger, a refrigerant spray pump, and a refrigerant circulation pump, and the first solution circulation pump for circulating the solution from the regenerator to the absorber is a solution pipe And a refrigerant pipe connected to form a solution / refrigerant circulation circuit, a heat source medium is introduced into the regenerator and the evaporator, cooling water is passed through the forward inclined condenser, and a heat source is supplied from the absorber. In the absorption heat pump that takes out the heated source medium above the temperature,
The absorber is connected with a flash tank through which the heated source medium circulates and a hot water pump, and the flash tank is provided with a third pressure sensor for detecting the pressure in the flash tank,
A three-way valve is provided on the outflow side of the pipe for circulating the heat source medium to the regenerator and the evaporator, and one of the three-way valves is connected to the inflow side by a pipe,
When the pressure detected by the third pressure sensor exceeds a preset value, the opening of the three-way valve is adjusted so as to reduce the flow rate of the heat source medium input to the regenerator and the evaporator. The control device is provided for adjusting the opening of the three-way valve so as to increase the flow rate of the heat source medium input to the regenerator and the evaporator when the set value is lower than a preset value. Absorption heat pump. A regenerator, a condenser, an evaporator, an absorber, a solution heat exchanger, a refrigerant spray pump, and a refrigerant circulation pump, and the first solution circulation pump for circulating the solution from the regenerator to the absorber is a solution pipe And a refrigerant pipe connected to form a solution / refrigerant circulation circuit, a heat source medium is introduced into the regenerator and the evaporator, cooling water is passed through the forward inclined condenser, and a heat source is supplied from the absorber. In the absorption heat pump that takes out the heated source medium above the temperature,
A hot water pump for circulating the heated source medium is connected to the absorber by piping, and a temperature sensor for detecting the temperature of the heated source medium taken out from the absorber is provided, and is detected by the temperature sensor. When the temperature exceeds a preset value, a control device is provided to control the rotation speed of the hot water pump to be decreased and when the temperature is lower than the set value, the control device is provided to increase the rotation speed of the hot water pump. Absorption heat pump.

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