JPH0670535B2 - Absorption heat pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to heat (hereinafter referred to as absorption heat) generated when a heat source fluid is supplied to an evaporator and a refrigerant of an absorbing liquid in an absorber is absorbed, and condensation of the refrigerant in a condenser. The present invention relates to improvement of an absorption heat pump that heats and heats a fluid to be heated such as hot water.

In this type of absorption heat pump, when the temperature of the heat source fluid supplied to the evaporator becomes too low or the temperature of the fluid to be heated supplied to the absorber becomes too high, saturated vapor of the absorption liquid sprayed to the absorber There is a problem that the pressure becomes higher than the refrigerant vapor pressure, the refrigerant vapor moves backward from the absorber to the evaporator and condenses in the evaporator, and normal heat pump operation cannot be performed.

That is, in this type of absorption heat pump, when the temperature of the heated fluid is higher than the temperature of the heat source fluid, the heat of the heated fluid supplied to the absorber is radiated to the heat source fluid supplied to the evaporator. There is a problem. When the temperature of the fluid to be heated here is higher than the temperature of the heat source fluid, the saturated vapor pressure of the absorbing liquid sprayed to the absorber by the temperature of the fluid to be heated and the heat source fluid temperature is higher than the refrigerant vapor pressure in the evaporator. It is said that there is a relationship that can be trained.

In view of this point, the present invention, in this type of absorption heat pump, uses a heat pump system for taking out a fluid to be heated by utilizing heat radiation from an absorber and a condenser, and heat of condensation of refrigerant vapor from a generator. A mechanism that constitutes a boiler system for taking out a fluid to be heated, detects a temperature of a heat source fluid supplied to an evaporator and a temperature of a fluid to be heated supplied to an absorber, and a heat pump system based on a signal from the mechanism. By adopting a configuration with a mechanism that switches between the and the boiler system,
The purpose is to stably raise the temperature of the fluid to be heated.

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, (1) has a combustion heating chamber (2) for kerosene or the like, and a generator that heat-separates the refrigerant vapor from the absorbing liquid, and (3) condenses and cools the refrigerant vapor from the generator (1). Condenser, (4)
Is an evaporator for vaporizing the refrigerant liquid from the condenser (3),
(5) is an absorber that absorbs the vaporized refrigerant from the evaporator (4) into an absorbing liquid, (6) is a solution heat exchanger, and these are refrigerant liquids having a refrigerant vapor pipe (7) and an on-off valve (8) A refrigerant pipe (9), a refrigerant circulation path (11) having a refrigerant pump (10),
Dilute liquid pipe (13) with solution pump (12) and concentrated liquid pipe (1)
4) Connected to form an absorption heat pump cycle.

(15) is a refrigerant liquid pipe with an on-off valve (16) that connects the condenser (3) and the generator (1), and the generator (1) and the condenser ( A refrigerant circulation cycle between 3) is formed.

(17) is a refrigerant blow pipe with an on-off valve (18) that connects the refrigerant circulation path (11) and the absorber (5), and (19) is a fuel supply pipe to the combustion heating chamber (2), A fuel control valve (20) is arranged in the pipe.

(21) is a heat source tube housed in the evaporator (4), (22) is a heated fluid take-out tube housed in the absorber (5) and the condenser (3), and has a three-way valve (23) in the tube. A bypass pipe (24) is provided to bypass the absorber (5).

(25) and (26) are detectors for detecting the temperature of the respective fluids supplied to the heat source pipe (21) and the heated fluid take-out pipe (22), and (27) are detectors (25), (26). Received the signal from
When the temperature of the heat source fluid is higher than the temperature of the fluid to be heated, the on-off valve (8) is opened, the absorber (5) side flow path of the three-way valve (23) is opened, the on-off valve (16) is closed, the three-way valve. The bypass pipe (24) side flow path of (23) is closed, and when the temperature of the heat source fluid is the same as or lower than the temperature of the fluid to be heated, the on-off valve (8) is closed, and the absorber of the three-way valve (23). It is a controller that closes the (5) side flow passage, opens the on-off valve (16), and opens the three-way valve (23) bypass pipe (24) side flow passage. The temperature of the heat source fluid and the temperature of the fluid to be heated are compared by comparing and calculating the signals from the detectors (25) and (26). This comparison operation
The heat source fluid temperature is x, the heated fluid temperature is y, and the temperature constant is k.
Then, which of the value of (x + k) and the value of y is larger is compared. The value of the temperature constant k is the absorber (5)
It is appropriately set according to the designed concentration of the absorbing solution to be sprayed on.

Then, a heat source fluid such as factory hot waste water or solar hot water is supplied to the heat source pipe (21), fuel is supplied to the combustion heating chamber (2) to drive the generator (1), and the heated object is heated. The fluid take-out pipe (22) is operated by flowing a heated fluid such as water.

(A) In the case of x + k> y (that is, in the case of heat source fluid temperature> heated fluid temperature) In this case, the controller (27) controls the on-off valves (16) (18)
Fully closed, the bypass pipe (24) side flow path of the three-way valve (23) is also fully closed, and the absorber (5) side flow path of the on-off valve (8) and the three-way valve (23) is opened for absorption. Heat pump operation,
A heated fluid to be heated is obtained from the take-out pipe (22).

That is, the heated fluid to be heated is taken out from the heat pump system that forms an absorption heat pump cycle and heats with the absorption heat in the absorber (5) and the refrigerant condensation heat in the condenser (3).

(B) When x + k ≦ y (that is, when heat source fluid temperature ≦ heated fluid temperature) In this case, the bypass pipe (24) side flow path of the three-way valve (23) is opened by the controller (27), The absorber (5) side flow path is closed, the on-off valve (16) is opened, and the on-off valve (8) is closed to operate, and the heated fluid to be heated is obtained from the take-out pipe (22).

That is, a heated fluid to be heated is taken out from a heat pump system that forms a refrigerant circulation cycle between the generator (1) and the condenser (3) and heats with the heat of refrigerant condensation in the condenser (3). .

In this case, open the on-off valve (18) to open the evaporator (4).
The non-evaporated refrigerant liquid inside is mixed with the absorption liquid inside the absorber (5) to dilute the concentration of the absorption liquid flowing back to the generator (1) to lower the absorption liquid boiling temperature inside the generator, It is preferable to save energy for raising the temperature. However, the refrigerant blow pipe (17) with the opening / closing valve (18) may not be provided.

In this way, by comparing the temperature of the heat source fluid and the temperature of the heated fluid and switching the heated fluid to either the absorption heat pump system or the boiler system, the reverse heat radiation from the heated fluid can be eliminated. It is possible to prevent and stably raise the temperature of the fluid to be heated.

Reference numeral (28) is a detector for detecting the temperature of the outlet side of the condenser (3) of the fluid to be heated, and the temperature controller (2
The opening of the fuel control valve (20) is controlled via 9), and the temperature at which the fluid to be heated is taken out is adjusted according to the load.

FIG. 2 is a drawing showing another embodiment of the present invention, in which the same elements as those in FIG. 1 use the same drawing numbers. In FIG. 2, (30) is a water heater attached to the generator (1), the upper part of the water heater is connected to the branch pipe (31) of the refrigerant vapor pipe (7), and the lower part is connected to the generator (1). ) Is connected to the refrigerant drain pipe (15) 'to form a refrigerant circulation cycle between the water heater (30) and the generator (1). (16) 'is an on-off valve arranged in the refrigerant drain pipe (15)'. Further, the heated fluid take-out pipe (22) housed in the absorber (5) and the condenser (3) is further housed in a water heater (30), and the heated fluid take-out pipe (22) has a three-way valve. (23) 'through absorber (5) and condenser (3)
A bypass pipe (24) 'is provided for bypassing. Also (2
5) 'is a pressure detector for detecting the vapor pressure in the evaporator (4), and (26)' is a pressure detector for detecting the vapor pressure in the absorber (5). In addition, (28) 'is a water heater (3
0) A detector that detects the outlet temperature.

Then, the signals from the pressure detectors (25) 'and (26)' are input to the controller (27) for calculation, and the internal pressure of the evaporator (4) is higher than the internal pressure of the absorber (5). In other words, when the temperature of the heat source fluid is higher than the temperature of the fluid to be heated, the controller (27) closes the flow path on the bypass pipe (24) 'side of the three-way valve (23)' and the open / close valve (16). ′ Is closed and the three-way valve (2
3) ′ opens the flow path on the condenser (3) side, forms an absorption heat pump cycle, and heats up with heat absorbed by the absorber (5) and heat of refrigerant condensation in the condenser (3). When the fluid to be heated is taken out and the internal pressure of the evaporator (4) is lower than the internal pressure of the absorber (5), in other words, when the heat source fluid temperature is lower than the heated fluid temperature, the controller (27)
To open the bypass pipe (24) 'side flow path of the three-way valve (23)' and open the on-off valve (16) 'to close the condenser (3) side flow path of the three-way valve (23)' to generate the generator ( A refrigerant circulation cycle is formed between 1) and the water heater (30), and the heated fluid to be heated is taken out from the boiler system that is heated by the heat of condensation of the refrigerant in the water heater (1).

Incidentally, instead of directly detecting the internal pressure of the absorber (5) and inputting a signal to the controller (27), a detector (26) ″ for measuring the specific gravity of the absorbing liquid dispersed in the absorber (5) and the absorption Control is performed by inputting a signal from a detector (26) that detects the temperature of the liquid into a calculator (32), calculating the concentration of the absorbing liquid and calculating the saturated vapor pressure of the absorbing liquid in the calculator. A signal may be input to the container (27).

As described above, according to the present invention, the generator, the condenser, the evaporator, the absorber, and the solution heat exchanger are connected by piping, and an absorption heat pump cycle is formed to heat the fluid to be heated by the absorption heat and the condensation heat of the refrigerant. Heat pump system and a boiler system that forms a refrigerant circulation cycle to heat the fluid to be heated with the heat of condensation of the refrigerant, and the temperature of the heat source fluid to be supplied to the evaporator and the fluid to be heated to be supplied to the absorber. A switch for extracting the heated fluid from the heat pump system when the temperature of the heat source fluid is higher and extracting the heated fluid from the boiler system when the temperature of the heated fluid is higher Since it has a mechanism, it is possible to prevent reverse heat radiation from the fluid to be heated and to stably raise the temperature of the fluid to be heated.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram of a circuit configuration showing one embodiment of the present invention, and FIG. 2 is a schematic explanatory diagram of a circuit configuration showing another embodiment of the present invention. (1) ... Generator, (2) ... Condenser, (4) ... Evaporator,
(5) ... Absorber, (6) ... Solution heat exchanger, (8) ... Open / close valve, (15) ... Refrigerant liquid pipe, (15) '... Refrigerant drain pipe,
(16) (16) '... open / close valve, (23) (23)' ... three-way valve,
(24) (24) '... bypass pipe, (25) (25)' ... detector, (26) (26) '(26) "(26) ... detector, (27)
… Controller, (30)… Water heater.

Claims (1)

[Claims] 1. A generator, a condenser, an evaporator, an absorber, and a solution heat exchanger are connected by piping to form an absorption heat pump cycle to heat a fluid to be heated by heat of absorption of refrigerant of absorption liquid and heat of condensation of refrigerant. Heat pump system and a boiler system that forms a refrigerant circulation cycle to heat the fluid to be heated with the heat of condensation of the refrigerant, and the temperature of the heat source fluid to be supplied to the evaporator and the fluid to be heated to be supplied to the absorber. A switch for extracting the heated fluid from the heat pump system when the temperature of the heat source fluid is higher and extracting the heated fluid from the boiler system when the temperature of the heated fluid is higher An absorption heat pump characterized by having a mechanism.