JPS602587B2 - Absorption heat pump heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to improve the heating performance of an absorption heat pump heating device that includes a liquid-cooled absorber as a component.

In general, air heat source heat pumps have a relationship in which the output decreases as the outside temperature decreases, while the heating load increases, so an auxiliary heat source is inevitably required.

Conventional electric compression heat pumps use electric Joule heating as an auxiliary heat source, resulting in low energy savings. In addition, with compression heat pumps, if the outside temperature becomes low and the cold pseudoliquid no longer evaporates in the air heat source evaporator, or if ice builds up on the evaporator and heat exchange is insufficient, the cold soot remains in liquid form. There is a risk of entering the compressor, causing liquid compression and destroying the compressor. Therefore, not only are various protective devices required, but when the heat pump is stopped, the output is only an auxiliary heat source and cannot cover the necessary heating load, so it can only be used in very warm areas. I have no choice. Heat pump heating using an absorption refrigeration cycle is highly energy efficient.
Also, since the ratio of heating output to cooling output is larger than that of compression heat pumps, it has the advantage of being suitable for colder regions.

However, even in absorption heat pumps, the contradiction between heating output and heating load mentioned earlier cannot be avoided, so an auxiliary heat source is necessary. The present invention relates to a method for adding an auxiliary heat source to an absorption heat pump.

First, the principle of an absorption heat pump will be explained with reference to FIG.

1 is a generator, and when heating is performed by burning gas etc. with a burner 2, refrigerant vapor is generated from a solution 3 in which the refrigerant is absorbed into an absorption liquid, and the refrigerant vapor is passed through a pipe 4 to a condenser installed in a heated space 5. It condenses at 6, and the condensation heat is used by the wind created by fan 7 to warm the indoor air.

The liquefied soot condensed in this step is transferred to the heated space 5 via piping 8.
evaporator 10 installed outdoors via a pressure reducing valve 9.
sent to. If the evaporation temperature is Te and the outside air temperature is Tam, if Te<Tam, the medium is evaporated in the evaporator 10 by extracting heat from the outside air. Air is forcibly sent to the evaporator 10 from the fan 11' to improve heat exchange with outside air.

The evaporated cold soot vapor flows into the absorber 3 through the pipe 12. On the other hand, in the absorber S3, a generator 1' is used to release cold soot vapor, and a high-temperature dilute solution with a reduced refrigerant content is transferred to the pipe 1.
4, passes through a heat exchanger 15, lowers its temperature by exchanging heat with a concentrated solution to be described later, passes through a flow rate regulating valve 16, and is poured into an absorber 13. There is also a cooling water pipe 17 inside the absorber turtle 3.
and the solution can be cooled.

The dilute solution poured into the absorber 13 absorbs the soot vapor and becomes a concentrated solution, but at this time a large amount of absorption heat is generated. This absorbed heat is taken away by the water flowing through the cooling water pipe 17. That is, the water leaves the absorber 13 heated. This hot water is sent to the radiator 19 installed in the heated space 5 through the piping 18, and heat is given to the indoor air by the wind generated by the fan 20, and the water is cooled and flows through the piping 21 and the water pump 22. After that, it returns to the absorber 13. On the other hand, the concentrated solution that absorbs refrigerant vapor in the absorber 13 and is cooled with cooling water passes through the pipe 23, is pressurized by the solution pump 24, and is heat exchanged with the high-temperature dilute solution in the heat exchanger 15. It is heated and fed into the generator 1 to complete the cycle.

As is clear from the above explanation, in the absorption heat pump, in addition to the heat given by the burner 2 in the generator 1, the heat given from the outside air in the evaporator 10 is
Since it is transferred to the air in the heated space 5 in the condenser 6 and the radiator 19, the heating output is the sum of both. The coefficient, that is, the value obtained by dividing the heating output by the heating input, is greater than 1, and is currently attracting much attention as an energy-saving device.

The important thing about this) is that, as explained above, unless the evaporation temperature Te is lower than the outside temperature Tam, evaporation will not occur.
Therefore, heat cannot be pumped up from outside air.

Therefore, when Tam<Te, the liquefied cold butterfly is transferred to the evaporator 1.
01 flows into the absorber 13 via the pipe 12 without being evaporated. In a compression heat pump, under such conditions, unevaporated liquid refrigerant will directly enter the compressor, creating an extremely dangerous situation. Generally, measures are taken to evaporate the soot, but in the case of an absorption type, there is no particular problem even if liquid refrigerant flows into the absorber; however, the amount of heat generated in the absorber is only the heat of mixing the liquid. Therefore, the heat of condensation is reduced compared to when absorbing the vaporizing medium, and the output is reduced to a fraction of that.

Also, even if the outside temperature Tam is higher than the evaporation temperature Te, the evaporator 10
If icing occurs, heat cannot be taken in from the air, and in this case as well, the liquefied cold soot flows into the absorber i3 without being evaporated, so the amount of heat generated in the absorber 13 decreases, but it does not interfere with operation. I don't want it. On the other hand, since the condensation of soot in the condenser 6 is independent of whether or not the soot is evaporated in the evaporator 10, the heat output from the condenser 6 is extracted regardless of outside air conditions.

However, the heat output from the radiator 19 naturally becomes smaller because the heat output from the absorber 13 is reduced. The present invention relates to means for compensating for this decrease in output.

FIG. 2 is a diagram illustrating the principle of an embodiment of the present invention.

The generator, condenser, and evaporator parts of the absorption heat pump are the same as in FIG. 1, and the common parts are given the same reference numerals.

In FIG. 2, the absorber 13 has a cooling water pipe 17, and the cooling water that enters from the cooling water inlet 25 is warmed by the absorbed heat generated in the absorber and comes out from the cooling water outlet 26.

In this case, if enough heat is absorbed from the outside air and the cold soot is completely evaporated in the evaporator 10, the absorber will generate heat corresponding to the condensation heat and mixing heat of the cold soot, and the water temperature at the cooling water outlet 26 will increase. reaches a temperature that can be used for heating, but when the outside temperature drops and the cold soot is no longer completely evaporated in the evaporator 10, the amount of heat generated in the absorber decreases by that amount, and when it no longer evaporates at all, The amount of heat generated in the absorber is reduced to a fraction of that of the mixed heat, and the heating output of this route is significantly reduced. Therefore, a heat exchanger 27 is provided in the middle of the pipe connecting the absorber cooling water outlet 26 and the radiator 19 provided in the space to be heated 5, and this is heated by combustion heat from the burner 28. Of course, this can be done by electric heating, but using electricity as heat is not a good idea from the standpoint of energy consumption. This burner 28 is controlled by a temperature detector 29 provided on the outlet side of the heat exchanger 27. If the temperature detected here falls below a predetermined temperature,
Burner 28 is ignited via controller 30. The control method may simply be an on/off control of ignition and extinguishing, but ``before the evaporation in the evaporator 10 reaches a state where it is not completely evaporated, there may be a state in which partial evaporation occurs, so at this time, the burner If the burner 28 outputs the same amount of heat output as when no evaporation is being performed, the output will be too large and the burner 28 will be turned on and off frequently. Therefore, it is better to perform proportional control so that the output of the burner 28 is proportional to the temperature difference. preferable.

It is also possible to provide a temperature detection point on the inlet side 301 of the heat exchanger 27, thereby enabling on-off control or stepwise control (including continuous control) of the burner.

Since this method does not form a negative feedback loop, the temperature of the water exiting the heat exchanger 27 is less stable than in the previously mentioned method, but it has the advantage of being easier to adjust. With the above configuration, even if the outside temperature drops significantly and, for example, it becomes impossible to evaporate cold soot in the 1QI evaporator, operation can be continued without reducing the heating output at all. .

In addition, by making it possible to manually change the set temperature that is the standard for turning on and off the burner 28, and by raising the set temperature above the hot water temperature that can be obtained during normal heat pump operation, the burner 28 can be turned on even when the heat pump is operating normally. Since it can be ignited, it is also possible to provide heating that exceeds the rated output of the heat pump.

This function is advantageous when you want to quickly heat a room, or when the outside temperature is extremely low and the heating load is large.

As described in detail above, the present invention takes advantage of the characteristics of absorption heat pumps to supplement the heat output of absorption heat pumps, has high energy efficiency, and is capable of reducing performance even when the outside temperature is low and the heating load increases. Not only does it not
It has an extremely superior effect, eliminating all the drawbacks of conventional electric compressor type heat pumps.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the principle of an absorption heat pump, and FIG. 2 is a diagram illustrating the principle of an absorption heat pump device in an embodiment of the present invention. 1... Generator, 2... Burner, 6... Condenser, 1
0...Evaporator, 13...Absorber, 17...
...Cooling water pipe, 19...Radiator, 22...
Water pump, 27...Heat exchanger, 28...
・Burner, 29. ．．・．． ．．・Temperature detector. Figure 1 Figure 2

Claims (1)

[Claims] 1 At least a generator, a condenser, an air heat source evaporator, and a liquid-cooled absorber form an absorption heat pump cycle, and the unevaporated refrigerant flows into the absorber. Also, a circulation path including a cooling liquid pipe of the absorber and a radiator, a heat exchanger provided between the high temperature side outlet of the cooling liquid in the absorber and the radiator, and the heat exchanger. An absorption heat pump heating device characterized in that a heating device is provided, and condensed heat in the condenser and absorbed heat radiated in the radiator are used as heat output. 2. The absorption heat pump heating device according to claim 1, wherein the heater is operated when the temperature of the cooling liquid becomes a predetermined temperature or lower.