JPH06100400B2 - Absorption heat pump device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an absorption heat pump device (hereinafter, referred to as a heat pump device) capable of extracting a fluid to be heated whose temperature is higher than that of a heat source fluid supplied to the device.
This type of device)) improvement.

(B) Conventional technology As a conventional technology of this type of apparatus, for example, Japanese Patent Laid-Open No. 58-693
What is found in Japanese Patent Publication No. 72 (hereinafter referred to as "first conventional device")
And those found in JP-A-58-136956 (hereinafter, referred to
Known as a conventional device), a low temperature heat source fluid such as waste steam or waste hot water is supplied to a generator and an evaporator to take out high temperature water from an absorber. Then, in the first conventional device, in order to prevent the refrigerant liquid amount in the condenser from excessively decreasing, the pump for sending the refrigerant liquid from the condenser to the refrigerant liquid reservoir of the evaporator is controlled to be started and stopped. ing. Further, in the second conventional device, when the amount of the refrigerant liquid in the condenser changes due to the change in the amount of heat energy supplied to the generator and the evaporator (hereinafter referred to as heat input), the evaporation from the condenser The flow rate of the refrigerant liquid sent to the refrigerant liquid reservoir of the container is controlled.

(C) Problems to be Solved by the Invention In this type of device, the condenser and the generator are operated at a lower temperature and pressure than the evaporator and the absorber. Therefore, the low temperature refrigerant from the condenser is controlled by the pump start / stop control. When the liquid is intermittently sent into the high temperature refrigerant liquid in the refrigerant liquid reservoir of the evaporator, hunting occurs in the temperature of the refrigerant liquid in the refrigerant liquid reservoir.

Therefore, in the first conventional device, the operating temperatures of the evaporator and the absorber fluctuate every time the pump starts and stops, and the temperature and heat quantity (hereinafter referred to as heat output) of the hot water taken out from the absorber are unstable. There is a problem that becomes.

On the other hand, in the second conventional device, although the heat output can be stabilized, it is necessary to use an expensive flow rate control valve or a variable discharge amount pump and highly accurate control is required, so that the control mechanism is expensive. It has a complicated problem. Further, for example, Japanese Patent Laid-Open No. 58-69372 discloses an absorption heat pump in which the operation of a pump for sending a refrigerant from a condenser to an evaporator is controlled by a liquid level controller provided in the condenser. In the absorption heat pump, operating efficiency decreases when outside air enters the equipment from the connection part of the liquid level detector, so the confidentiality of the flow path becomes a demanding issue. When it is provided in the condenser which is the flow path of the refrigerant, there is a possibility that outside air may enter from the connecting portion.

In view of these problems, the present invention suppresses the invasion of the outside air into the flow paths of the refrigerant and the absorbing liquid, stabilizes the operation efficiency, and uses an inexpensive and simple control mechanism to evaporate with the fluctuation of the heat input. It is an object of the present invention to provide a device of this type capable of stabilizing the heat output by reducing the hunting of the operating temperature of the absorber and the absorber.

(D) Means for Solving the Problems In the device of this type, the present invention is used as a pump for sending the absorbing liquid from the generator to the absorber and as a pump for sending the refrigerant liquid from the condenser to the evaporator, and reverse energization. A reversible pump that sometimes discharges less liquid than when normally energized, a drain tank that is installed in the middle of the flow path of waste vapor and drain that flows out of the generator and evaporator, and a drain tank, and this drain tank When the liquid level detector and a signal from this liquid level detector are input and the detected value exceeds the set value, each reversible pump is energized normally, and when the detected value is below the set value, each reversible pump is energized reversely. And a control mechanism.

(E) Action In this type of device according to the present invention, as its action, the fluctuation range of the amount of condensed refrigerant sent to the refrigerant sump of the evaporator can be made smaller than that of the first conventional device, and the fluctuation of the heat input is increased or decreased. On the other hand, since the circulation amount can be controlled to increase or decrease while continuing the circulation of the absorbing liquid and the refrigerant liquid, the fluctuation of the amount of refrigerant generated is smaller than that of the first and second conventional devices, and the operating pressure of the device Reduced temperature hunting. In addition, the liquid level detector for operation control of the reversible pump is installed in the drain tank different from the circulation path of the refrigerant and the absorbing liquid, and even if a leak occurs at the connection part of the liquid level detector, the absorption heat pump device Ingress of outside air can be avoided and operation efficiency is stabilized. Further, since the control is to switch the energization of the pump based on the set value of the detected value, the control is similar to the on / off control, and a simple and inexpensive control mechanism can be used.

As described above, the device of this type according to the present invention can reduce hunting of the operating temperature of the evaporator and the absorber due to the fluctuation of the heat input by a simple and inexpensive control mechanism, and can prevent external air from entering the device. This device has a high practical value as a device that can avoid the intrusion and stabilize the heat output as compared with the conventional device.

(F) Embodiment FIG. 1 is a schematic structural explanatory view showing an embodiment of an apparatus of this kind according to the present invention. In FIG. 1, (1),
(2), (3), (4) and (5) are a generator, a condenser, an evaporator, an absorber and a solution heat exchanger, respectively, and (6), (7) and (8) are condensed respectively. Pumps for refrigerant, refrigerant liquid circulation, and absorption liquid. Then, these devices are equipped with pipes (9), (1
0), refrigerant liquid recirculation pipes (11), (12), absorption liquid sending pipes (13), (14), (15), absorption liquid flowing pipes (16), (17) Refrigerant [water] and absorption liquid [lithium bromide aqueous solution] similar to conventional devices of this type
It constitutes the circulation circuit of. In addition, (18) is a heat transfer coil built in the solution heat exchanger (5).

(19), (20), (21) and (22) are a heater, a cooler, and a supply unit built in the generator (1), the condenser (2), the evaporator (3) and the absorber (4), respectively. And (23), (24), (25) and (26) of the generator (1), condenser (2), evaporator (3) and absorber (4), respectively. It is a liquid reservoir. Further, (27) and (28) are sprayers for absorbing liquid, and (29) is a sprayer for refrigerant liquid.

(30), (31), (32), (33), (34) are heaters (1
9) and a heat supply device (21) connected in parallel to a pipe through which a low temperature heat source fluid such as waste steam or waste hot water flows, and (35) and (36) are cooling water and cooling connected to a cooler (20). Pipes (37) and (38) through which a cooling fluid such as working air flows are pipes through which a heated fluid such as hot water or hot air that is connected to the heated device (22) flows.

In the device configured as described above (hereinafter referred to as the present device), an absorption heat pump cycle is formed by circulation of the refrigerant and the absorbing liquid, as in the conventional device of this type, and the generator (1) and the condenser ( 2) operates at a lower temperature and pressure than the evaporator (3) and the absorber (4), and the absorption liquid sprinkled on the heated device (22) of the absorber (4) is the refrigerant vapor from the evaporator (3). The fluid to be heated having a temperature higher than that of the heat source fluid supplied to the evaporator (3) by the heat generated when absorbing the
It is obtained from 2).

(39) indicated by the chain double-dashed line in the figure is a drain tank when waste steam is used as the heat source fluid, and the waste steam and drain flowing out from the heater 19 and the heat absorber 21 are drained as indicated by the arrows. It flows into the tank (39). Further, the drain tank (39) is provided with a waste vapor discharge pipe (40), a drain discharge pipe (41) with a valve (V), and a liquid level detector (LS1). Here, when the waste steam of the heat source fluid is used, the amount of condensation of this waste steam in this device, that is, the increase / decrease change in the liquid level in the drain tank (39) indicates the increase / decrease change in the heat input of this device.

(C) is a controller that receives a signal from the liquid level detector (LS1), compares the detector with a reference set value, and switches the energization to the pump (6) and the pump (8) between normal and reverse directions. Is. The (6) and the pump (8) are reversible pumps in which the amount of discharged liquid is smaller during reverse energization than during normal energization. Fig. 2 shows an example of the performance curve of such a reversible pump.
With respect to the liquid discharge amount of, the liquid discharge amount is 60 to 40% in the reverse rotation during reverse energization.

Next, an operation example of this device using a reversible pump having the performance shown in FIG. 2 will be briefly described.

For example, when the heat input is reduced to half (50%) during the operation of this device, the heat input becomes insufficient with respect to the amount of the absorbed liquid sprayed to the heater (19), and the refrigerant vapor in the generator (1) The amount of generation decreases sharply. Along with that, the amount of condensation of the refrigerant vapor in the condenser (2) also decreases. Further, the amount of drain flowing into the drain tank (39) is reduced, and the drain liquid level becomes equal to or lower than the set value. Then, the energization of the pumps (6) and (8) is switched from normal energization to reverse energization via the controller (C) by the signal of the liquid level detector (LS1), and the liquid discharge amount of these pumps is almost halved. Reduced. As a result, the circulation amount of the absorbing liquid between the generator (1) and the absorber (4) is reduced to about half, and the amount of the absorbing liquid sprayed to the heater (19) is almost halved with respect to the half heat input. Therefore, the refrigerant vapor is efficiently and stably generated in the generator (1). Further, the outflow amount of the refrigerant liquid from the liquid reservoir (24) is almost halved, and is almost balanced with the amount of the refrigerant condensed while flowing from the generator (1) to the condenser (2).
The liquid level of the liquid reservoir (24) is maintained near the set value, and the refrigerant liquid is stably sent to the evaporator (3). Therefore, in this device, the operating temperature and operating pressure of the devices such as the generator (1), the condenser (2), the evaporator (3), and the absorber (4) are maintained at a value commensurate with the heat input at half. Stable operation is continued. Then, when the heat input returns to 100%, the energization of the pumps (6) and (8) is returned from the reverse energization to the normal energization again.

In this way, in this device, the fluctuations in the heat input, that is, the fluctuations in the amount of waste steam, are detected by the fluctuations in the drain amount in the drain tank (39), and the pumps (6) and (8) are controlled. As a result, hunting of the operating temperature and operating pressure of the device can be reduced and the operation can be stabilized. further,
As shown in FIG. 1, the liquid level detectors (LS1), (LS2), the temperature detector (TS) and the pressure detector (PS) are attached in the middle of the flow paths of the refrigerant and the absorbing liquid, and the pump (6), When (8) is controlled, there is a high possibility that outside air, which is a non-condensable gas, will enter, but when the liquid level detector (LS1) is provided in the drain tank (39) as in the present invention. In addition, it is possible to prevent outside air from entering the refrigerant flow path and the absorption liquid flow path of the absorption heat pump device from the mounting portion, and as a result, it is possible to maintain high operation efficiency.

(G) Effect of the Invention The present invention is an absorption heat pump device configured as described above, and it is possible to reduce the circulation amount of the absorbing liquid and the refrigerant liquid by reducing the heat input and reversely energizing the reversible pump. Therefore, the operation of the absorption heat pump device can be stabilized against the fluctuation of the heat input, and as a result, the hunting of the operating temperature of the device can be reduced as compared with the conventional device, and the heat output can be stabilized. Of course, since the detector for the liquid level that changes in relation to the increase or decrease of heat input, that is, the amount of waste steam, was installed in the drain tank different from the flow paths for the refrigerant and the absorbing liquid, The outside air can be prevented from entering the refrigerant channel and the absorbing fluid channel of the device, and as a result, the operating efficiency can be maintained high. In addition, the control mechanism is simple and easy to switch the energization of the reversible pump used as the pump for the condensed refrigerant and the pump for the absorbing liquid, so that the control mechanism is cheaper and simpler than the conventional device.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory view showing an embodiment of an apparatus of this type according to the present invention, and FIG. 2 is a diagram showing an example of a performance curve of a reversible pump used in the apparatus according to the present invention. (1) ... Generator, (2) ... Condenser, (3) ... Evaporator, (4) ... Absorber, (5) ... Solution heat exchanger,
(6), (7), (8) ... Pump, (19) ... Heater, (20) ... Cooler, (21) ... Heater, (22) ...
Heated device, (23), (24), (25), (26) ... Liquid reservoir, (27), (28), (29) ... Sprayer, (30), (3
1), (32), (33), (34) …… pipe, (39) …… drain tank, (C) …… controller, (LS ₁ ), (LS ₂ ), (LS ₃ ) ……
Liquid level detector, (PS) ... pressure detector, (TS) ... temperature detector.

Claims (1)

[Claims] 1. A generator, a condenser, so as to circulate a cooling fluid through a condenser, supply waste steam to a generator and an evaporator, and take out a heated fluid above a temperature level of waste steam from an absorber.
In a device with an evaporator and an absorber piped, it is used as a pump that sends absorption liquid from the generator to the absorber and as a pump that sends refrigerant liquid from the condenser to the evaporator. Reversible pump with few
A drain tank is provided in the middle of the flow path of waste vapor and drain that flows out from the generator and evaporator, and a drain level sensor is installed in this drain tank, and a signal is input from this level sensor. The absorption heat pump device is provided with a control mechanism for normally energizing each reversible pump when the detected value exceeds a set value and reversely energizing the reversible pump when the detected value is less than the set value.