JPS62297672A - Absorption refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to an improvement in an absorption refrigerator of the type in which unvaporized refrigerant in an evaporator is recirculated to the evaporator by a refrigerant liquid pump. .

(Conventional Technology) As a conventional technology for the above-mentioned type of absorption refrigerator, as seen in, for example, Japanese Utility Model Publication No. 50-43416 and Japanese Utility Model Publication No. 51-16051, the lower end of the condensed refrigerant flow pipe is evaporated. A device connected to a refrigerant reservoir of a container (hereinafter referred to as the first conventional example 5) is known.As another conventional technique, for example, Japanese Patent Laid-Open No. 59-109753 and Japanese Patent Laid-Open No. 5
As seen in Japanese Patent No. 9-173666, there is a known method in which the lower end of a condensed refrigerant flow pipe is connected to a refrigerant liquid return flow path on the discharge side of a refrigerant liquid pump (hereinafter referred to as a second conventional example). .

P→ Problem to be Solved by the Invention In the first conventional example, the condensed refrigerant flows down to the low-pressure side evaporator at a temperature close to the condensation temperature and self-evaporates while flashing violently. In addition to this, the amount of heat exchanged with the refrigerant in the heat exchanger of the evaporator decreases, and in addition to this, the liquid level in the refrigerant reservoir of the evaporator violently ripples due to the flash, and a large amount of refrigerant liquid overflows into the solution reservoir of the absorber and is absorbed. There is a problem that it cannot be used for freezing purposes.

In the second conventional example, the condensed refrigerant joins the low-temperature unvaporized refrigerant sent by the refrigerant liquid pump and flows to the evaporator while lowering the temperature, so the refrigerant flashes as violently as in the first conventional example. However, on the other hand, when the pressure difference between the condenser and evaporator becomes small, such as during low load, when the cooling water temperature drops, or at startup, some of the unvaporized refrigerant discharged by the refrigerant liquid pump In some cases, the refrigerant flows back toward the condenser, or the condensed refrigerant hardly flows down, resulting in a reduction in the heat exchange area between the condenser cooler and refrigerant vapor, and the need to permanently install a cavity in the refrigerant liquid pump. However, there is a problem that depending on the pressure conditions, it may cause malfunction of the absorption chiller.

The present invention addresses these problems and easily achieves alleviation of flash evaporation of the refrigerant flowing into the evaporator and stagnation of the condensed refrigerant in the condenser at times of low load or when cooling water temperature drops. The purpose is to provide an absorption refrigerator that is capable of

B.) Means for solving the problems The present invention, as a means for solving the above problems,
In the absorption refrigerator of the above type, a flow rate control valve is provided in the refrigerant liquid return path from the refrigerant liquid pump discharge side to the connection part with the condensed refrigerant flow pipe, and condensation is controlled by the opening degree of this valve. It is configured to be controlled by a signal from a liquid level detector provided in the refrigerant liquid reservoir of the container.

(E) Effect According to the present invention, when the liquid level in the refrigerant liquid reservoir of the condenser begins to rise, the opening degree of the flow rate control valve is reduced by a signal from the liquid level detector, and the refrigerant liquid bonder is activated. Since the absorption refrigerating machine can have the effect of suppressing the flow of the unvaporized refrigerant being sent, the resistance of the unvaporized refrigerant to the condensed refrigerant flow at the confluence point of the unvaporized refrigerant and the condensed refrigerant is weakened, and the flow of the condensed refrigerant is promoted. As a result, even when the pressure difference between the condenser and the evaporator becomes small, such as when the cooling water temperature drops or when starting It is possible to easily alleviate stagnation within the country.

In addition, since the condensed refrigerant joins the unvaporized refrigerant and flows to the evaporator while lowering its temperature, flash evaporation of the refrigerant within the evaporator is also reduced.

(v) Embodiment The drawings are schematic configuration explanatory diagrams showing one embodiment of the absorption refrigerator according to the present invention, in which (1) shows a high temperature generator, (2) shows a low temperature generator (3) and a condenser (4). a generating condenser consisting of (5
) is an evaporator-absorber consisting of an evaporator (6) and an absorber (7), (8) is a low-temperature solution heat exchanger, (9) is a high-temperature solution heat exchanger, (P, ) is a refrigerant liquid pump, ( Pl) is a bonder for absorbing liquid, and by connecting these devices with piping, a circulation path for refrigerant [water] and absorbing liquid [lithium bromide aqueous solution] is formed, and an absorption refrigerator is constructed.

Ql is the combustion heating chamber of the high temperature generator (1), aυ is the heater of the low temperature generator (3), α2 is the cooler of the condenser (4), 03
) is the heat exchanger of the evaporator (6), 041) is the absorber (7)
al, 051... are combustion gas passages, (161 are combustion gas exhaust passages, (171, cold water pipes connected to QI & home heat exchanger Q31, 0!1, ■, υ
is cooler Q41. This is a cooling water pipe line in which α2 is connected in series.

(23, C! □□□, (2a, (c), 弼, (5) are the absorption liquid pipes, respectively, and (to) is the connection between the gas phase part of the high temperature generator (1) and the heater qυ. C32 is the refrigerant vapor conduit, and C32 is the refrigerant drain conduit connecting the heater (11) and the condenser (3).
1 is a refrigerant liquid distribution device installed in the heat exchanger 03 + upper evaporator (6), and (c) is a refrigerant liquid pipe connecting the refrigerant liquid reservoir c31) and the suction port of the refrigerant liquid pump (Pl). Road, 04
) is the refrigerant liquid bonder (PI) discharge port and refrigerant liquid sprayer 0)
These refrigerant liquid pipes and the refrigerant liquid pump (Pa) form a refrigerant liquid return path in the evaporator (6).

and (Sl), (S,) are the 11th condenser (4)
It is the second refrigerant liquid reservoir, and C351 has its upstream end as the second refrigerant reservoir.
This is a U-shaped refrigerant liquid flow conduit whose one downstream end is connected to the refrigerant liquid reservoir (St) bottom and connected to the refrigerant liquid conduit (b).

() is the refrigerant liquid pipe line 0 (1
) is a flow rate control valve provided in the second refrigerant reservoir (S, ), and the opening degree of this valve is determined by a signal according to the rise in the liquid level sensed by the liquid level detector (T, S) provided in the second refrigerant liquid reservoir (S, ). While it is controlled to decrease through the controller (C), it is controlled to increase in accordance with the drop in the sensing liquid level. The liquid level detector (LS) uses an electrode type liquid level sensor, an optical liquid level sensor, etc.

Note that when the condenser (4) does not have the second refrigerant liquid reservoir (S), the liquid level detector (LS) is connected to the first refrigerant liquid reservoir (S).
) will be deployed.

Next, an example of the operation of the absorption refrigerating machine (hereinafter referred to as the present machine) configured as described above will be explained.

During rated operation of the machine (for example, during mid-summer operation, the temperature of the cooling water flowing into the machine is about 32°C, and the condenser (4
) The internal pressure is maintained at about 56 miHP, and the difference between this and the internal pressure of the evaporator (6) is maintained at about 50 mmH5F,
When the liquid level in the second refrigerant reservoir (S2) is at approximately a predetermined height, the flow control valve (V) is opened at a predetermined opening degree.

By the way, in spring or autumn, when the temperature of the cooling water flowing into the machine is about 19°C, the internal pressure of the condenser (4) is about 28 x mHP, and the difference between this and the internal pressure of the evaporator (6) is about 22 x mH5'. When this machine is operated, the force with which the condensed refrigerant tries to flow down the refrigerant liquid flow pipe (toward) is reduced to about half of the rated operation, while the discharge force of the refrigerant liquid pump (Pl) increases. That is, at the confluence point of the condensed refrigerant and the unvaporized refrigerant, the force of the unvaporized refrigerant to block the flow of the condensed refrigerant becomes stronger, so that the second refrigerant liquid reservoir (S,
) begins to rise. In this case, if the liquid level continues to rise, the supply of condensed refrigerant to the evaporator (6) will decrease significantly, and the refrigerant liquid in the refrigerant reservoir Gυ will eventually run out and the refrigerant liquid bonder (Pa) The condensed refrigerant may fill the first and second refrigerant reservoirs m (81) and (Sm), causing cavitation in the low temperature generator (3).
The refrigerant vapor from this generator and the cooler (
The heat exchange area with 12 will be drastically reduced, leading to poor alignment and driving problems.

In this case, in this machine, the second refrigerant liquid reservoir (S,)
As the liquid level rises in the refrigerant, the flow rate control valve is narrowed down by the signal from the liquid level detector (T, S), the flow resistance of the unvaporized refrigerant at this valve increases, and the unvaporized refrigerant at the above-mentioned confluence point is reduced. Since the blocking force of the refrigerant against the flow of the condensed refrigerant is weakened, the flow of the condensed refrigerant is promoted. Then, the endless rise in the liquid level of the condensed refrigerant stops, the liquid level is maintained at a certain level, and the opening degree of the flow rate control valve (V) is also at a certain value [in this case, the opening degree is almost close to fully closed]. is fixed. As a result, the condensed refrigerant overflows to the low temperature generator (3) side and the refrigerant liquid pump (
P, ) cavitation is prevented and good operation continues. Note that when the cooling water inflow temperature becomes higher than 19°C, the internal pressure of the condenser (4) increases, and the second refrigerant liquid reservoir (S
, ) decreases, the opening degree of the flow control valve (■) increases.

In this way, in this machine, the condenser (4) and the evaporator (
6) Adjust the reflux resistance of the unvaporized refrigerant according to changes in the pressure difference between the refrigerant and the evaporator (6). The flow rate of the cooling water can be maintained approximately within a predetermined range, and operation when the cooling water temperature is low or at startup can be performed satisfactorily. This also applies when this device is used as a heat pump.

Furthermore, in this machine, the condensed refrigerant joins the unvaporized refrigerant at a low temperature (for example, about 6° C.) to lower its temperature, and then flows into the evaporator (6), so that flash evaporation is also significantly reduced.

In addition, in this machine, the refrigerant liquid reservoir 61) of the evaporator (6)
A means for increasing or decreasing the opening degree of the flow control valve (V) by installing a liquid level detector (LS) at the
(not shown), but since there is not necessarily a correlation between the change in the liquid level of the condensed refrigerant and that of the unvaporized refrigerant, the above method may cause an excessive liquid level of the condensed refrigerant. Not the preferred method.

(G) Effects of the Invention As described above, the present invention alleviates the stagnation of refrigerant liquid in the condenser when the pressure difference between the condenser and the evaporator is small, that is, the congestion of the flow of condensed refrigerant, and reduces the problem such as during startup. It provides an absorption chiller with the effect of improving the operation of the refrigerant and the effect of reducing flash evaporation of the condensed refrigerant to maintain high operating efficiency. It has high practical value.

It goes without saying that the present invention can also be applied to a single-effect absorption refrigerator.

[Brief explanation of the drawing]

The drawing is a schematic structural explanatory diagram showing one embodiment of an absorption refrigerator according to the present invention. (1)...High temperature generator, (3)...Low temperature generator,
(4)... Condenser, (6)... Evaporator, (7
)...Absorber, (8), (9)...Low temperature, high temperature solution heat exchanger, (P,)...Refrigerant liquid pump, 0
υ...Refrigerant liquid reservoir, 0)...Refrigerant liquid spreader, profit,
01... Refrigerant liquid pipe line, c39... Refrigerant liquid flow pipe line, (SI), (S,)... Refrigerant liquid reservoir part, (
LS)...liquid level detector, (C'5...controller,
Seki...Flow control valve.

Claims (1)

[Claims] (1) A refrigerant that connects equipment such as a generator, condenser, evaporator, and absorber with piping to form a circulation path for refrigerant and absorption liquid, and returns unvaporized refrigerant from the evaporator to the evaporator using a refrigerant liquid pump. In an absorption refrigerator that forms a liquid return path and connects the refrigerant liquid pump discharge side of this return path to the downstream end of a condensed refrigerant distribution pipe, a liquid level is formed in the refrigerant liquid reservoir of the condenser. A flow control valve, which is equipped with a detector and whose opening degree is adjusted to decrease or increase depending on the height of the detected liquid level, is connected from the refrigerant liquid pump discharge side of the refrigerant liquid return path to the condensed refrigerant distribution pipe. Absorption refrigerators are characterized by being deployed on the way to.