JPH0646126B2 - Double-effect absorption refrigerating machine of cold temperature switching type - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention takes out cold water and other cold fluids by the latent heat of vaporization of a refrigerant, while hot water and other The present invention relates to a double-effect absorption refrigeration machine of a cold temperature switching type adapted to take out warm fluid (hereinafter referred to as a double-effect absorption refrigeration machine of this type).

(B) Conventional technology As a conventional technology of this type of double-effect absorption refrigerator, high-temperature refrigerant vapor generated in the high-temperature generator bypasses the generation condenser (can body) consisting of the low-temperature generator and the condenser. There is known a pipe provided with a cold / hot switching valve (valve) so as to flow to an evaporator (can barrel) [see, for example, Japanese Patent Publication No. 46-15823]. As another conventional technique, cold temperature switching is performed so that the high-temperature refrigerant vapor generated in the high-temperature generator and the heated high-temperature absorbing liquid bypass the generated condenser and flow to the evaporative absorber composed of the evaporator and the absorber. Those equipped with a pipe line equipped with a valve [cooling / heating switching valve] [for example, JP-A-51-148]
No. 858] is known.

(C) Problems to be solved by the invention In this type of double-effect absorption refrigerator, the resistance to the flow of refrigerant from the high temperature generator side to the evaporator side bypassing the condenser is generated from the high temperature generator side. It is smaller than that for the flow of refrigerant through the condenser to the evaporator side. Therefore, in the conventional double-effect absorption refrigerator of this type, during heating operation, most of the refrigerant vapor generated in the high temperature generator flows directly to the evaporative absorber side and almost flows to the generated condenser side. However, the internal pressure of the generated condenser tends to be lower than the internal pressure of the evaporative absorber. Then, during the cooling operation, the absorbing liquid already accumulated in the low temperature generator or the absorbing liquid gradually flowing from the high temperature generator side to the low temperature generator via the solution heat exchanger begins to stay in the low temperature generator as it is, and Since the refrigerant liquid in the condenser also does not flow to the evaporative absorber side, during the heating operation of this type of double-effect absorption refrigerator, the amount of liquid circulating between the absorber and the high temperature generator gradually decreases and the solution pump There was a problem that the cavitation and overheating of the high temperature generator were likely to occur.
In particular, this problem is likely to occur in a compact double-effect absorption refrigerator of this type, which has almost no valve in the solution pipe because it is necessary to maintain airtightness with the outside air.

In view of this problem, the present invention can reduce the retention of the liquid in the generated condenser during the heating operation, and can perform stable heating operation by preventing cavitation of the solution pump and empty heating of the high temperature generator. It is intended to provide a double-effect absorption refrigerator of a kind.

(D) Means for solving the problems The present invention is, as a means for solving the above problems, a high temperature generator side and a generation condenser side or a generation condenser side of a double-effect absorption refrigerator of this type. The evaporative absorber side is connected by a pressure equalizing pipe with an on-off valve that is opened during heating operation.

(E) Action In this type of double-effect absorption refrigerator according to the present invention,
During the heating operation, the action (work) of keeping the evaporative absorber side at a lower pressure than the generating condenser side or at the same pressure as the generating condenser side is provided. Due to this action, the liquid in the generation condenser flows to the evaporative absorber side, and the retention of the liquid in the generation condenser is alleviated, and the solution circulating between the high temperature generator and the absorber is excessively reduced. Therefore, it is possible to reliably prevent the cavitation of the solution pump and the overheating of the high temperature generator, which enables stable heating operation.

(F) Embodiment FIG. 1 is a schematic configuration explanatory view showing an embodiment of this type of double-effect absorption refrigerator according to the present invention. In FIG. 1, (1) is a high-temperature generator, (2) is a gas-liquid separator, (3) is a low-temperature generator (4) and a condenser (5) on the upper trunk side, and (6) )
Is an evaporative absorber on the lower trunk side consisting of an evaporator (7) and an absorber (8),
(9) and (10) are low-temperature and high-temperature solution heat exchangers, (11) is a bubble pump, (12) is an electric solution pump, and these devices have a pumping pipe (13) through which absorption liquid flows. Tube (14), (15), (16),
(17), pipes (18), (19), (20), (21) to which the absorption liquid is sent, pipes (22), (23), (24) through which the refrigerant flows, and pipes (2) through which the refrigerant liquid flows down.
5), absorption refrigeration using the same refrigerant [water] and absorption liquid [lithium bromide aqueous solution] as in the conventional double-effect absorption refrigerator of this type, which is connected by refrigerant liquid reflux pipes (26), (27) The cycle is structured. Then, cold water is obtained by the latent heat of vaporization of the refrigerant in the evaporator (7) in this absorption refrigeration cycle.

(T _B ) is a bypass line for refrigerant vapor and absorption liquid that connects the gas-liquid separator (2) and the evaporation absorber (6), and this line has a cold / hot switching valve such as a solenoid valve or a motorized valve. (V _CH ) is provided, and by opening this cold / hot switching valve, the cycle of the refrigerant and the absorbing liquid is configured as in the conventional absorption refrigerator of this type. Then, hot water is obtained by the latent heat of condensation of the refrigerant vapor in the evaporative absorber (6) in this cycle or by this heat and the sensible heat of the absorbing liquid.

(28) is the burner of the high temperature generator (1), (29) is the low temperature generator (4)
Heater, (30) cooler of condenser (5), (31) evaporator (7)
Heat exchanger, (32) is the cooler of the absorber (8), (33),
(34) is a load side heat exchange unit (not shown) and a heat exchanger (3
A pipe through which cold water or hot water that connects (1) and (35), (3
6) and (37) are cooling water flow pipes in which the coolers (32) and (30) are connected in series. In addition, (S _G ) and (S _A ) are low temperature generators, respectively.
(4) is a solution reservoir of the absorber (8), and (S _C ) and (S _E ) are refrigerant reservoirs of the condenser (5) and the evaporator (7), respectively.

Furthermore, (38) is an overflow pipe for absorbing liquid with a steam trap (39) that connects the gas-liquid separator (2) and the low temperature generator (4), and (40) is the low temperature generator (4). It is a U-shaped overflow pipe for absorbing liquid, which is connected to the absorber (8). Also,
(41) is a conduit with an orifice (42) connecting the U-shaped overflow pipe (40) and the pipe (19), and (43) connects the pipe (26) and the lower part of the absorber (8). This is a refrigerant blow conduit with a valve (44).

And (T _P1 ) is a pressure equalizing pipe that connects the low temperature generator (4) and the absorber (8), and this pipe opens and closes the manual valve, solenoid valve, motorized valve, etc. that are opened during hot water extraction operation. A valve (V _P ) is provided.

In the cold-temperature switching type dual-effect absorption refrigerator (hereinafter referred to as this machine) configured as described above, the switching valve (V _P ) is opened and the low temperature generator (4) is opened at the time of switching to the hot water extraction operation. ) In the solution reservoir (S _G ) flows down to the solution reservoir (S _A ) in the absorber (8) on the lower trunk side via the pressure equalizing pipe (T _P1 ), thereby generating the generated condenser (3). The evaporative absorber (6) is connected to equalize the pressure. For this reason, in this machine, when the hot water is taken out, it is generated like a conventional double temperature absorption refrigerating machine with a cold temperature switching type condenser.
The pressure on the (3) side never becomes lower than that on the evaporative absorber (6) side.
Then, during the hot water extraction operation, all of the absorbing liquid that gradually flows from the high temperature generator (1) side to the low temperature generator (4) via the pipes (14) and (15) passes through the pressure equalizing pipe (T _P1 ) and then the absorber. Solution reservoir of (8) (S _A )
The refrigerant liquid in the condenser (5) also flows down to the solution reservoir (S _A ) via the pipe (25) and the refrigerant liquid reservoir (S _E ) of the evaporator (7), and these liquids are in solution. It is returned to the high temperature generator (1) by the pump (12). In this way, in this machine, since the retention of the liquid in the generated condenser (3) during the hot water extraction operation is alleviated and the uneven distribution thereof is reduced, the cavitation of the solution pump (12) and the high temperature generator. It is possible to reliably prevent the dry heating of (1) and continue stable operation.

In addition, in this machine, connect the upper end of the pressure equalizing pipe (T _P1 ) to the low temperature generator.
Not only at the bottom of the solution reservoir (S _G ) of (4), but also at any place in the vapor condenser of the low-temperature generator (4), the condenser (5), etc. Is also good. When opened except for the bottom of the solution reservoir (S _G ), the absorbing liquid in the low temperature generator (4) mainly flows down to the absorber (8) via the pipes (16) and (17). Further, one end of the pressure equalizing pipe (T _P1 ) may be connected to the U-shaped overflow pipe (40).

FIG. 2 is a schematic structural explanatory view showing another embodiment of this type of double-effect absorption refrigerator according to the present invention (cold temperature switching type double-effect absorption refrigerator), and the embodiment shown in this figure. In FIG. 1, the same components as those of the embodiment shown in FIG. 1 are designated by the same reference numerals. In Figure 2, (T _P2 ) is the tube (22)
And a generating condenser (3), which is a pressure equalizing pipe, and this pipe is provided with an on-off valve ( _VP ) that is opened during the operation of taking out hot water. Note that (S _G1 ) and (S _G2 ) are the first and second solution reservoirs of the low temperature generator (4), respectively.

In the embodiment shown in FIG. 2, the on-off valve ( _VP ) is opened during the hot water extraction operation so that the gas-liquid separator (2), that is, the high temperature generator (1) side and the generator condenser (3) side are connected. Are communicated with each other and the pressures are almost the same, and the evaporation absorber (6) is kept at a lower pressure than the generation condenser. Therefore, almost all of the liquid in the generation condenser (3) flows to the evaporative absorber (6) side and is returned to the high temperature generator (1).

In this example, one end of the pressure equalizing pipe (T _P2 ) is connected to the pipe (2
It may be connected to 3) and the other end may be opened to the condenser (5) side. Further, although not shown, in the case of forming a gas phase part in the high temperature generator (1) itself (that is, in the case of an absorption refrigerator without using the gas-liquid separator (2)), the gas phase of this high temperature generator Pressure equalizing pipe (T
One end of _P2 ) may be opened.

(G) Effect of the invention As described above, in the cold-temperature switching type double-effect absorption refrigerator of the present invention, the evaporative absorber side is kept at the same pressure as the generated condenser side or a lower pressure than this when the warm fluid is taken out. Since almost all of the liquid in the generated condenser is returned to the high temperature generator via the evaporative absorber, uneven distribution of the liquid, cavitation of the solution pump and empty heating of the high temperature generator can be prevented.
The operation of taking out the warm fluid can be stably continued. Needless to say, the cooling water is cut off when the warm fluid is taken out.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory view showing an embodiment of this type of double-effect absorption refrigerator according to the present invention, and FIG. 2 is another embodiment of this type of double-effect absorption refrigerator according to the present invention. It is a schematic structure explanatory view showing an example. (1) …… High temperature generator, (2) …… Gas-liquid separator, (3) …… Generation condenser, (4) …… Low temperature generator, (5) …… Condenser, (6) ……
Evaporative absorber, (7) …… Evaporator, (8) …… Absorber, (9), (1
0) ... low temperature, high temperature solution heat exchanger, (12) ... solution pump,
(13) …… Pumping pipe, (14), (15), (16), (17) …… Pipe, (1
8), (19), (20), (21) ... tube, (22), (23), (24), (25)
…… Pipe, (31) …… Heat exchanger, (40) …… U-shaped overflow pipe, (T _B ) …… Bypass conduit, (V _CH ) …… Cold temperature switching valve, (S _G ), (S _G1 ), (S _G2 ), (S _A ) ... Solution reservoir, (S _C ), (S
_E ) …… Refrigerant reservoir, (T _P1 ), (T _P2 ) …… Pressure equalizing tube, (V _P ) ……
On-off valve.

Claims (1)

[Claims] 1. A refrigerant vapor generated in a high temperature generator and / or a heated absorption liquid bypasses a generation condenser composed of a low temperature generator and a condenser and flows to an evaporation absorber composed of an evaporator and an absorber. In a double-effect absorption refrigerator with a line with a cold / hot switching valve, with an on-off valve that connects between the high temperature generator side and the generation condenser side or between the generation condenser side and the evaporation absorber side A double-effect absorption refrigeration machine of the cold temperature switching type, which is equipped with a pressure equalizing pipe.