JPH0451320Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a solution concentration adjusting device for an absorption chiller/heater.

[Background of the idea]

FIG. 1 shows a general example of a water-lithium chlorine absorption chiller/heater. This absorption chiller/heater is equipped with a device for adjusting the concentration of the solution, and the present invention relates to an improvement of this solution concentration adjusting device.

First, we will briefly explain the outline of absorption chiller/heater.
Refrigerant vapor A generated by the evaporator 1 is absorbed by an absorbent (concentrated solution of lithium salt aqueous solution, hereinafter referred to as concentrated solution) B in the absorber 2. Here, the solution C whose concentration has decreased by absorbing the refrigerant (hereinafter referred to as dilute solution) is transferred to the heat exchanger 4 by the solution circulation pump 3.
It is sent to the first regenerator 5 through the. A dilute solution C heated by a gas burner 6 in the high-temperature regenerator 5 is separated into a high-temperature refrigerant vapor D and an intermediate concentrated solution E by a gas-liquid separator 8 through a pipe 7. Among them, the high-temperature refrigerant vapor D is led to the low-temperature regenerator 9 and heats the intermediate concentration solution E introduced through the heat exchanger 4 again. This heating further increases the concentration of solution E and generates intermediate temperature steam G. The intermediate temperature steam G is liquefied in the condenser 10. This condensation is performed by the cooling water H flowing through the pipe 11. The liquefied solution I enters the evaporator 1 via the refrigerant tank 13,
Subjected to freezing action. On the other hand, the solution E is sent to the heat exchanger 4 via the pipe 14, and after its heat is transferred to the dilute solution C, it is sent to the absorber 2 via the pipe 15, where it acts as a concentrated solution B. Thereafter, freezing is performed by repeating the above-mentioned cycle.

Next, the density adjustment device will be explained. A pipe (hereinafter referred to as first pressure detection pipe) 16 for detecting the pressure of the evaporator 1 from the refrigerant tank 13 is disposed in the upper part of the solution concentration adjustment chamber 17, and is used to detect the pressure of the condenser 10 from the condenser 10. Piping for detection (hereinafter referred to as
This is called the second pressure detection pipe. ) 18 is arranged at the bottom of the solution concentration adjustment chamber 17. That is, this solution concentration adjustment device adjusts the pressure difference between the condenser 10 and the evaporator 1 as the cooling water inlet temperature increases.
The supply of liquid refrigerant to the evaporator 1 is gradually reduced to increase the storage of liquid refrigerant in the solution concentration adjustment chamber 17, and the concentration of the solution in the absorber 2 is increased to ensure the refrigerating capacity. As the inlet temperature decreases, the supply of liquid refrigerant to the evaporator 1 is gradually increased to dilute the concentration of the solution in the absorber 2 to prevent crystallization of the solution and freezing of the refrigerant.

However, in the above-mentioned conventional solution concentration adjustment device, when the operation of the absorption chiller/heater is stopped, the liquid refrigerant that has been stored is released into the machine, and when restarting the machine, the liquid refrigerant is reused to reach the optimum solution concentration. need to be stored.

Therefore, although the stored liquid refrigerant is discharged every time the cooling is stopped, this discharged refrigerant does not contribute to the refrigeration capacity at all and is an ineffective refrigerant, which deteriorates the refrigeration coefficient of performance. Furthermore, since the solution is excessively diluted when restarting the operation, there is a problem that the start-up time of the operation becomes longer.

[Purpose of invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a solution concentration adjusting device that can eliminate ineffective refrigerant during refrigeration operation and shorten the start-up time during restart.

[Structure of the idea]

In order to achieve the above object, the solution concentration adjustment device according to the present invention closes the second pressure detection pipe between the condenser and the solution concentration adjustment chamber when refrigeration operation is stopped, and stabilizes the operation of the absorption chiller/heater when restarting operation. The present invention is characterized in that a valve is provided that is controlled to open the second pressure detection pipe with a time delay.

According to this configuration, since the valve is closed when the refrigeration operation is stopped, release of ineffective refrigerant is prevented, and when the refrigeration operation is restarted, the valve is opened after waiting for the water chiller/heater to stabilize, so that the solution concentration can be maintained at an optimum state. Therefore, the start-up time can be shortened.

[Example of idea]

Embodiments of the solution concentration adjusting device according to the present invention will be described below with reference to the drawings.

FIG. 2 shows an embodiment of the present invention. In FIG. 2, the same parts as in FIG. 1 are given the same reference numerals, and their explanation will be omitted.

The main difference in FIG. 2 from FIG. 1, that is, the point related to the present invention, is that a solenoid valve 19 is provided in the second pressure detection pipe 18. This solenoid valve 19 is controlled to open and close as follows (see FIG. 3).
The solenoid valve 19 is kept open at Td during normal refrigeration operation of the absorption chiller/heater. By doing so, liquid refrigerant I matching the temperature of the cooling water H is stored in the concentration adjustment chamber 17. Next, at Ts when the refrigeration operation is stopped, the solenoid valve 19 is closed at the same time as the refrigeration operation is stopped. Then, the liquid refrigerant I at the time of stop remains stored in the concentration adjustment chamber 17, and discharge of the ineffective refrigerant is prevented. Next, when restarting the operation, the solenoid valve 19 is opened after a certain period of time Δt. The fixed time Δt is the time required for the operation of the absorption chiller/heater to reach a stable state. This delay time may be set, for example, by a timer 20 provided in a control circuit of an operation panel (not shown) of the refrigerator. Since the electromagnetic valve 19 is opened after entering a stable state in this manner, the liquid refrigerant I is not diluted unnecessarily, and therefore the operation start-up time is shortened and the refrigeration coefficient of performance is improved.

The above control is performed sequentially by a control circuit of an operation panel (not shown).

In this embodiment, a solenoid valve is used as the valve, but any other valve that can be controlled ON-OFF can be used, and the present invention is not limited to this embodiment.

[Effect of idea]

As described above, by providing a valve in the second pressure detection pipe and closing the pipe line to prevent the release of the stored refrigerant in the solution concentration adjustment chamber when the refrigeration operation is stopped, the release of the ineffective refrigerant is prevented, and the refrigerating operation is resumed. Since the valve is opened after a delay until the operation of the refrigerator becomes stable, the operation can be started with a high concentration of liquid refrigerant, and the operation start-up time can be shortened. . With such a configuration, an improvement in the coefficient of performance can be expected.

[Brief explanation of the drawing]

Fig. 1 is a piping diagram showing an example of a conventional absorption chiller/heater, Fig. 2 is a piping diagram showing an example of the solution concentration adjusting device according to the present invention, and Fig. 3 is an explanatory diagram of valve operation in the present invention. It is. DESCRIPTION OF SYMBOLS 1... Evaporator, 10... Condenser, 17... Solution concentration adjustment chamber, 18... Second pressure detection piping, 19...
...Solenoid valve, 20...Timer, H...Cooling water, I...
...Liquid refrigerant, Ts...When freezing operation is stopped, Tr...When restarting operation, △t...Delay time.

Claims (1)

[Claim for Utility Model Registration] Solution concentration adjustment in an absorption chiller/heater that increases the amount of liquid refrigerant stored in the solution concentration adjustment chamber in response to the pressure difference between the condenser and evaporator caused by an increase in cooling water inlet temperature. In the apparatus, when the refrigeration operation is stopped, a pipe arranged between the condenser and the solution concentration adjustment chamber is closed, and when the refrigerating operation is started, a valve is opened to open the pipe after a delay of time for the absorption chiller/heater to stabilize. A solution concentration adjusting device for an absorption chiller/heater, characterized in that it is provided in the pipe.