JPH07243713A - Absorption chiller - Google Patents

Abstract

(57) [Summary] [Structure] The role of partitioning the condenser 13 and the evaporator 1 into a U-shape by the liquid refrigerant 4 during cooling, and the bubble pump that conveys the refrigerant in the evaporator 1 to the absorber 5 during heating. A gas-liquid separation duct 19 having a baffle 20 therein is provided in the middle of the heating steam pipe that shares the role of 16 to separate the liquid refrigerant 4 and the steam 14,
The vapor 14 is guided to the evaporator 1, the liquid refrigerant 4 is guided to a place where there is no absorber heat transfer tube, and the liquid refrigerant 4 necessary for heating operation is absorbed in the absorber 5
Supply to. [Effect] The liquid refrigerant can be returned to the absorber without directly sprinkling it on the absorber heat transfer tube.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption chiller-heater which forms a heating cycle for heating with steam from a condenser.

[0002]

2. Description of the Related Art A heating cycle of a conventional absorption chiller-heater is shown in FIG. The refrigerant vapor for heating is taken out from the condenser 13, blows through the vapor pipe 15, flows into the evaporator 1, and is used for heating hot water. At this time, since the liquid refrigerant condensed in the evaporator does not operate the refrigerant pump 2, the pipe 6 branched from the refrigerant pump discharge pipe through the inside of the stopped refrigerant pump.
As a result, it is guided to the valley of the steam pipe 15 and is conveyed to the absorber 5 by the action of the bubble pump 16 that sucks up the liquid refrigerant by using the refrigerant vapor flowing in the steam pipe 15 as a drive source.

[0003]

In the conventional cycle as shown in FIG. 1, the liquid refrigerant of the evaporator, which is conveyed to the absorber by the bubble pump 16 during the heating operation, is jetted to the absorber together with the vapor and absorbed. There is a large difference in concentration with the concentrated absorbent that circulates in the reactor, increasing the risk of corrosion of the heat transfer tubes on which the liquid refrigerant descends in the absorber, making operation impossible for many years.

[0004]

The present invention provides the following as means for solving the above problems.

(1) Before the liquid refrigerant condensed in the evaporator during heating is conveyed to the absorber by the bubble pump, a duct having a larger cross-sectional area than the heating steam pipe is provided, and only the vapor is guided from the duct to the evaporator.

(2) By providing a baffle plate while vapor and liquid refrigerant flow in the duct, the liquid refrigerant hits the baffle plate in the duct and collects in the duct without being conveyed to the absorber. . The steam passes between the baffles and flows into the evaporator, which contributes to heating.

(3) A pipe is provided in the lower part of the duct to connect it to a portion of the absorber where there is no heat transfer pipe.

[0008]

[Operation] By these means, there is the following operation.

(1) The liquid refrigerant condensed in the evaporator during heating is
After passing through the stopped refrigerant pump, it is guided from the refrigerant discharge pipe, flows in the heating steam pipe as a vapor-liquid two-layer flow of vapor and liquid refrigerant, and rises toward the inflow portion provided in the upper part of the evaporator. By providing a duct with a larger cross-sectional area than the heating steam pipe in the middle of this, the flow velocity of the vapor and liquid refrigerant drops, the liquid refrigerant with a large specific gravity falls down, and the vapor flows to the evaporator. Play a role.

(2) During heating, the vapor-liquid two-layer flow of the steam and the liquid refrigerant flowing through the heating steam pipe is reduced in the duct according to the present invention, and then the liquid refrigerant hits the baffle according to claim 2. Collect in the duct without being conveyed to the absorber. The steam passes between the baffles and flows into the evaporator, which contributes to heating.

(3) At the time of heating, the liquid refrigerant accumulated in the lower part of the duct by (1) and (2) is introduced from the lower part of the duct to a place where there is no absorber heat transfer tube, so that the liquid refrigerant having a large concentration difference is transferred to the heat transfer tube. Since it is not directly applied to the surface, corrosion does not progress.

[0012]

EXAMPLE An example of the present invention will be described with reference to FIG.

First, FIG. 2 shows a cooling cycle.

By operating the refrigerant pump 2 with the evaporator 1, the liquid refrigerant is sprayed from the refrigerant spraying device 3 to the heat transfer tubes 17 and evaporated. At that time, the cold water flowing through the heat transfer tube 17 is cooled and provided for cooling. The refrigerant vapor generated in the evaporator 1 is absorbed by the solution sprayed on the absorber 5. The absorbed heat generated at this time is radiated to the cooling water flowing in the heat transfer tube 18. The solution that has absorbed the refrigerant vapor in the absorber 5 is conveyed by the solution pump 7, is partially supplied to the high temperature regenerator 10 through the high temperature heat exchanger 9 and the low temperature heat exchanger 8, and is otherwise supplied. It is supplied to the low temperature regenerator 11. The solution in the high temperature regenerator 10 is heated by the heating source of the combustor 12 to generate a refrigerant vapor and concentrate it. On the other hand, the solution of the low temperature regenerator 11 is
The refrigerant vapor generated in the high-temperature regenerator 10 is heated as a heating source to generate and concentrate the refrigerant vapor. Here, the refrigerant vapor used as a heating source is liquefied and flows into the condenser 13 as a liquid refrigerant.

The refrigerant vapor generated in the low temperature regenerator 11 is cooled and condensed by the cooling water flowing in the heat transfer tube 18 in the condenser 13, and returned to the evaporator 1 together with the liquid refrigerant from the low temperature regenerator 11.

On the other hand, the low temperature regenerator 11 and the high temperature regenerator 1
The solution generated by generating the refrigerant vapor at 0 and concentrated is returned to the absorber 5 via the high-temperature heat exchanger 9 and the low-temperature heat exchanger 8 and is scattered.

In this cooling cycle, the steam pipe 1
5, the bubble pump 16 and the refrigerant supply pipe 6 function as follows.

During cooling, it is necessary to prevent the refrigerant vapor in the condenser 13 from escaping from the vapor pipe 15 to the evaporator 1. Therefore, the liquid refrigerant is supplied to the valley portion of the steam pipe 15 from the pipe 6 branched from the discharge of the refrigerant pump 2. The liquid refrigerant forms a U-seal, absorbs the pressure difference between the condenser 13 and the evaporator 1, and can partition the condenser 13 and the evaporator 1.

On the other hand, the upper liquid surface position of the liquid seal is elevated by a lift necessary for the refrigerant spraying device 3 to spray the liquid refrigerant, but the inlet portion to the evaporator 1 is located higher than the liquid surface. Therefore, the liquid refrigerant in the liquid seal is not transported to the absorber 5. The gas-liquid separation duct according to the present invention has no effect during cooling by being installed above the liquid level above the liquid seal.

Next, FIG. 3 shows a heating cycle.

The circulation route of the solution during heating is the same as that during cooling. The circulation of the refrigerant will be described. When heating
It is necessary to constantly transfer the liquid refrigerant in the evaporator 1 to the solution side to keep the solution concentration low. Further, the refrigerant pump 2 and the cooling water are stopped. Since the refrigerant pump 2 is stopped,
No liquid refrigerant is supplied to form the liquid seal.

The refrigerant vapor generated in the low temperature regenerator 11 flows into the vapor pipe 15 via the condenser 13. In addition, a part of the refrigerant vapor generated in the high temperature regenerator 10 passes through the condenser 13 as the refrigerant vapor together with the refrigerant vapor generated in the low temperature regenerator 11 through the steam pipe 15, and a part thereof is liquefied in the low temperature regenerator 11. The liquid refrigerant returns to the evaporator 1.

Since the liquid seal is not formed in the steam pipe 15 as described above, the refrigerant vapor flowing in the steam pipe 15 is
It serves as a drive source for the bubble pump 16. The bubble pump 16 guides the liquid refrigerant in the evaporator 1 through a pipe 6 branched from the discharge of the refrigerant pump 2 having a function of supplying the liquid refrigerant in order to form a liquid seal during cooling, and the liquid refrigerant and the refrigerant vapor are separated from each other. A two-layer flow is introduced together to the gas-liquid separation duct according to the present invention. The flow velocity of the liquid refrigerant is reduced in the duct, and when passing through the baffle plates, the liquid refrigerant has a large specific gravity and drops down to separate from the vapor and collect in the lower part of the duct. The steam passes between the baffles and flows into the evaporator, which contributes to heating. The liquid refrigerant accumulated in the lower part of the duct is guided to a place where there is no absorber heat transfer tube by the pipe according to the present invention, and serves to keep the absorber at a low concentration.

The refrigerant vapor thus flowing into the evaporator 1 heats the hot water flowing in the heat transfer tube 17 in the evaporator 1 and is liquefied to be a liquid refrigerant, which is guided to the bubble pump 16 as described above.

[0025]

In the heating operation, the vapor-liquid separation duct is provided in the heating vapor pipe that conveys the evaporator refrigerant from the bubble pump to the absorber, and the accumulated liquid refrigerant is guided to the absorber so that the liquid refrigerant flowing into the evaporator is removed. Since it can be minimized and the liquid refrigerant can be prevented from directly falling on the absorber heat transfer pipe, a long-life absorption chiller-heater can be realized. Further, since it is possible to use the conventional heating steam pipe, it is not necessary to draw a separate pipe for gas-liquid separation, which leads to downsizing and cost reduction of the absorption chiller / heater.

[Brief description of drawings]

FIG. 1 is an explanatory view of a conventional heating cycle.

FIG. 2 is an explanatory diagram of a cooling cycle according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a heating cycle according to another embodiment of the present invention.

[Explanation of symbols]

1 ... Evaporator, 2 ... Refrigerant pump, 3 ... Refrigerant spraying device, 4 ...
Liquid refrigerant, 5 ... Absorber, 6 ... Refrigerant supply pipe, 7 ... Solution pump, 8 ... Low temperature heat exchanger, 9 ... High temperature heat exchanger, 10 ... High temperature regenerator, 11 ... Low temperature regenerator, 12 ... Combustor, 13 ... Condenser, 14 ... Refrigerant vapor, 15 ... Steam piping, 16 ... Bubble pump, 17 ... Chilled water heat transfer tube, 18 ... Chilled water heat transfer tube, 19 ...
Gas-liquid separation duct, 20 ... Baffle plate, 21 ... Refrigerant return pipe.

Claims (1)

[Claims] 1. An absorption chiller-heater including an evaporator, an absorber, a low temperature regenerator, a high temperature regenerator, and a condenser, which has a U-shaped steam pipe for guiding steam from the condenser to the evaporator, An absorption chiller-heater characterized in that a duct having a larger cross-sectional area than the steam pipe is provided before entering the evaporator.