JPH0417338B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses an organic absorbent and refrigerant, and uses an absorption refrigeration cycle to produce an absorption refrigerator (hereinafter referred to as an absorption refrigerator) that is used for cold water cooling, ice making, heat pumps, etc. Regarding.

Absorption chillers have a mechanism that heats the liquid that has absorbed the refrigerant and reseparates the refrigerant, so it does not start steady operation until the absorption liquid reaches a certain temperature, so it has the disadvantage that it takes time to start. ing. For this reason, a mechanism as shown in FIG. 1, for example, has been used to quickly raise the temperature of the generator of the absorption chiller.
In other words, 1 is a generator of the absorption chiller, 2 is a condenser, 3 is an evaporator, and 4 is an absorber. The absorption liquid in the absorber 4 is returned to the generator 1 by a pump 7, and the absorption liquid pump 7 stops operating until the temperature of the liquid in the generator 1 rises. , the liquid temperature rose faster.

However, in absorption refrigerators that use organic liquids as working fluids such as absorbents or refrigerants, if the heating is done simply to raise the liquid temperature, the generator 1
This is not preferable because local heating of the liquid within the tank tends to cause deterioration of the working fluid.

The present invention was developed in view of these points, in order to prevent local heating of the working fluid in the generator and to quickly increase the temperature of the fluid in the generator, the suction side of the generator and the absorption fluid pump are connected to each other. The system is connected by a side pipe with an on-off valve, and when the absorption chiller starts operating, a pump is used to generate a flow of working fluid while transitioning to steady operation.An embodiment of the present invention is shown below. This will be explained according to the drawings.

Figure 2 shows Freon in the combination of refrigerant and absorbent.
22-Tetraethylene glycol dimethyl ether system, trifluoroethanol-N-alkyl 2-pyrrolidone system, or other organic refrigerant absorbent is used in the absorption chiller. , a generator that gasifies and separates the refrigerant from the absorption liquid by heating and boiling the absorption liquid that has absorbed a large amount of refrigerant (hereinafter referred to as concentrated liquid); 10 separates the absorbent component from the rising refrigerant gas flow; The rectifier 11 is a partial condenser in which the gas stream sent from the rectifier 10 is cooled by a heat exchanger 12 for final separation of absorbent components.

13 is an evaporator having a built-in heat exchanger 14, which is liquefied in a condenser 15, reduced in pressure by a pressure reducing valve 16, and vaporized by giving heat from the heat exchanger 14 to the sprayed liquid refrigerant; 17 in the generator 1; The absorption liquid (hereinafter referred to as diluted liquid) whose refrigerant concentration has been reduced by separating the refrigerant is depressurized by the pressure reducing valve 18 and sprayed from the sprayer 19, thereby absorbing the refrigerant gas vaporized by the evaporator 13, thereby causing evaporation. The absorber 13 is an absorber that continuously absorbs heat from the low temperature fluid flowing through the heat exchanger 14, and the concentrated liquid that has absorbed the refrigerant in the absorber 17 is transferred to the heat exchanger 21 by an absorption pump 20. The refrigerant is then dispersed from the liquid dispersion device 22 to the filling material 24 of the recovery section 23 of the rectifier, and flows down to the generator 8 while coming into contact with the gas flow rising from the generator 8, where the refrigerant is reseparated.

25 is the generator 8 and the absorption liquid pump 20.
This is a side pipe equipped with an on-off valve 26 that connects the suction side S of the on-off valve 26, and the opening and closing of the on-off valve 26 is controlled as described later by a controller 27 that receives the temperature or pressure of the generator 8 as input. Also, 28 is a demultiplexer 11, a condenser 1
5. Heat exchangers 12 and 2 built into the absorber 17
This is a switching valve that limits the amount of cooling fluid such as water or brine (air that is forced through in the case of an air-cooled heat exchanger) flowing through the heat exchangers 9 and 30.

The operation of such a configuration will be explained below. When the absorption chiller starts operating, the liquid temperature in the generator 8 is low and the pressure is also low, so the controller 27 which takes any of these physical quantities as input is the on-off valve 26.
is open, and in this state, the combustor 9 is ignited to start heating the concentrated liquid in the generator 8, and the absorption liquid pump 2 is turned on.
0, the absorption liquid of the generator 8 flows through the on-off valve 2.
6. It is sucked into the suction side S of the pump 20 through the side pipe 25, passes through the spargeer 22 and the recovery section 23, and is circulated again so as to flow down from the upper part of the generator 8.
The concentrated liquid in the generator 8 is forcedly circulated together with the convection generated by heating, and the probability that the liquid in the generator 8 is locally heated and deteriorates in quality can be reduced. At this time,
The cooling fluid is caused to flow only to the heat exchanger 30 of the absorber 17 by the switching valve 28, and to the condenser 15 and the demultiplexer 1.
1 is not cooled and the amount of heat dissipated is reduced, so the pressure of the generator 8 can be increased to quickly shift to steady operation as in the conventional case.

In this way, when the temperature of the concentrated liquid in the generator 8 rises and reaches the temperature and pressure that enable steady operation, the controller 27
closes the on-off valve 26 and stops the liquid flow passing through the side pipe 25, so that the refrigerant flow gasified in the generator 8 passes through the rectifier 10 and the demultiplexer 11 to the condenser 15. The diluted absorption liquid is distributed to the absorber 17, and is transferred to the heat exchangers 30 and 2 by the switching valve 28.
At 9 and 12, cooling fluid (heated fluid in the case of a heat pump) is passed through, and the operation shifts to steady state.

Although not clearly shown in the figure, in order to make it easier for the liquid to be sucked into the pump 20 through the side pipe 25 at the time of startup, the liquid outlet A of the generator 8 must be connected to the liquid suction port S of the pump 20. It is preferable to provide it at a higher position. Further, 31 is a controller for the switching valve 28.

FIG. 3 shows another embodiment of the invention, in which the same equipment as in FIG. 2 is designated by the same reference numbers.

In the embodiment shown in FIG. 3, an on-off valve 33 is attached to the dilute liquid pipe 32, and a switching valve 28' is attached to the fluid pipe 34.
A pump 35 for cooling fluid is provided. The operation of the on-off valve 26 and the switching valve 28 is the same as the explanation in FIG. 2, but the on-off valve 33 provided in the diluted liquid pipe 32 is closed at the time of startup, opened when transitioning to steady operation, and is opened when steady operation is started. At the same time, valve control is performed so that the diluted liquid is sprayed into the absorber 17.

The operation of the switching valves 28 and 28' is controlled by a controller having a sensor for detecting the cooling fluid temperature, similar to the sensor 35' and controller 31 of the absorption chiller shown in FIG. It is also possible to prevent the cooling fluid from flowing through all of the heat exchangers 30, 29, and 12 until steady operation is achieved.

In this way, in the absorption chiller of the present invention,
The liquid outlet of the generator of the absorption refrigeration cycle and the suction side of the absorption liquid pump are connected by a side pipe with an on-off valve, and the liquid in the generator is heated while flowing with the pump. Even when a refrigerant absorbent is used, the risk of the absorbent being altered by partial heating is reduced, and the temperature can be raised efficiently, which speeds up the transition to steady operation of the absorption chiller and improves the efficiency of conventional operation. Compared to similar absorption chillers, the heating device of the generator can be made smaller in size.

[Brief explanation of drawings]

Fig. 1 is a cycle configuration diagram showing an example of a conventional absorption chiller, Fig. 2 is a cycle configuration diagram showing an embodiment of an absorption chiller according to the present invention, and Fig. 3 is a cycle configuration diagram showing another embodiment. It is a diagram. 8~generator, 15~condenser, 13~evaporator, 1
7 - absorber, 20 - absorption liquid pump, 25 - side pipe, 26 - on-off valve, 27 - controller, 28, 28'
~Switching valve, 31~Controller.

Claims (1)

[Claims] 1. A generator that separates the absorbent component from the gas stream heated and vaporized by the generator and converts it into refrigerant gas, a condenser that cools and liquefies the refrigerant gas, and a device that obtains heat from the fluid from outside the machine and converts it into liquid refrigerant. The system is equipped with an evaporator that vaporizes the refrigerant, and an absorber that absorbs the vaporized refrigerant by dispersing an absorption liquid in which the refrigerant has been separated and the refrigerant components have been reduced in the generator, and these generators, condensers, evaporators, and absorbers In an absorption cooler using an organic absorbent and refrigerant, the absorbent and refrigerant are connected in an airtight manner to form a circulation cycle between the absorbent and the refrigerant, in which the absorbent at the bottom of the absorber is returned to the generator by a pump. a side pipe with an on-off valve that connects the generator and the suction side of the absorption liquid pump; a controller that opens the on-off valve at the start of operation and closes it during steady operation; and an absorber when the on-off valve is released. or a controller for controlling the flow rate of fluid supplied to a heat exchanger of a condenser.