JPH07218028A - Absorption type refrigerating machine - Google Patents

Abstract

PURPOSE:To prevent chilled water and refrigerant from being supercooled by rapidly suppressing evaporation capacity in an evaporator and absorption capacity in an absorber. CONSTITUTION:The title refrigerating machine is equipped with a first system for detecting reductions in cooling load and in temperatures of chilled water and refrigerant, a second system capable of stopping cooling water within an absorber 5 to reduce the absorption capacity of the absorber 5 and a third system capable of simultaneously stopping a refrigerant pump 3 to reduce the evaporation capacity of an evaporator 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigerating machine, and more particularly, when the set temperature of the cold water outlet is low and there is a sharp decrease in the cooling load or when there is a margin to the subcooling trip temperature during low load operation. The present invention relates to an absorption chiller that can continue stable operation even when there is no such chiller.

[0002]

2. Description of the Related Art Conventionally, when there is a sharp decrease in the cooling load or when a low load operation below the heating source throttle control range is performed, as shown in Japanese Patent Application No. 4-157788, the absorber and evaporator are A method is known in which a solution and a refrigerant bypass pipe are provided to suppress the absorption capacity.

[0003]

The drawbacks of the prior art are reduced by bypassing the spray quantity by the refrigerant pump, so that the pump continues to operate. Therefore, it is necessary to prevent adverse effects such as pump cavitation, especially when the load is low.

[0004]

The above-mentioned problems are solved by stopping the refrigerant pump.

[0005]

The refrigerating capacity generated in the evaporator largely depends on the evaporation capacity of the evaporator and the absorption capacity of the absorber. Refrigerant capacity is immediately reduced by stopping the refrigerant pump to reduce the amount of evaporation of refrigerant on the heat transfer tubes in the evaporator and at the same time by stopping the cooling water pump to reduce the absorption capacity in the absorber. Therefore, the problem of chilled water temperature or refrigerant temperature being overcooled is solved.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

First, the cooling cycle of the absorption refrigerator will be described with reference to FIG.

The evaporator 1 is kept at about one-hundredth atmospheric pressure, in which the refrigerant 2 (water) is sprayed by the refrigerant pump 3 onto the evaporator heat transfer tube 4 through which the cold water passes, thereby removing the heat of the cold water. Evaporate to produce a cooling effect. The evaporated refrigerant vapor flows into the absorber 5 kept at a low pressure by the cooling water, and is absorbed by the aqueous solution of lithium bromide sprayed on the absorber heat transfer tube 6, and the aqueous solution of lithium bromide becomes rare. This dilute solution is sent to the high temperature regenerator 9 and the rest to the low temperature regenerator 10 through the heat exchanger 8 by the solution pump 7, and is heated by the direct heat source 11 such as a burner in the high temperature regenerator 9 and vaporized. And separated into a concentrated solution. In the low temperature regenerator 10,
The dilute solution is heated by the steam generated in the high temperature regenerator 9 and separated into steam and concentrated solution. The concentrated solution thus concentrated is sprayed again into the absorber 5 via the solution heat exchanger 8. The drain heated and condensed in the low temperature regenerator 10 is guided to the condenser 12. Further, the refrigerant vapor generated in the low temperature regenerator 10 is condensed in the condenser 12. The condensed refrigerant thus produced is guided to the evaporator 1 and sprayed to complete the cycle.

Next, an embodiment of the present invention will be described with reference to FIG. 1, a sensor 13 is added to the chilled water outlet, and a control device 15 for controlling the cooling water pump 14 and the refrigerant pump 3 is added to the chilled water outlet in accordance with the signals from the sensor 13. If the cooling load suddenly decreases or the load falls below the heating source throttle control range while the absorption chiller is in operation, the cooling capacity before the load decreases until the concentrated concentrated solution is diluted Therefore, there is a problem that the chilled water temperature and the refrigerant temperature become supercooled and the operation cannot be continued. Therefore, the sensor 13 detects that the cooling load has decreased or the chilled water temperature or the refrigerant temperature has dropped, and the control device 15 causes the refrigerant pump 3 and the cooling water pump 14 to operate.
To stop. As a result, the refrigerant evaporation capacity of the evaporator 1 is immediately suppressed, and at the same time, the absorption capacity of the absorber 5 is suppressed. This solves the problem that the cold water temperature and the refrigerant temperature are overcooled. Reference numeral 16 represents a cooling tower.

[0010]

According to the present invention, the stable operation can be continued without the cooling water and the refrigerant temperature being overcooled even when the load is sharply reduced or the cooling load is below the heating source throttle control range. An absorption refrigerator can be provided.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a cooling cycle of the absorption refrigerator.

[Explanation of symbols]

 1 ... Evaporator, 2 ... Refrigerant pump, 5 ... Absorber.

Claims (1)

[Claims] 1. An absorption refrigerating machine comprising an evaporator, an absorber, a condenser, a high temperature regenerator, a low temperature regenerator, a solution heat exchanger, a solution pump, a refrigerant pump, and a piping system for operatively connecting them. Detecting a decrease in cooling load, or a decrease in cold water temperature or refrigerant temperature, stop the cooling water pump that flows cooling water in the heat transfer tube in the absorber, and stop the refrigerant pump to increase the refrigerating capacity. An absorption chiller, which is equipped with a mechanism to reduce it.