JPH0379627B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for starting an absorption chiller utilizing an absorption refrigerant cycle to obtain heated fluid used for space heating or hot water supply or cooled fluid used as a refrigerant.

Since the absorption refrigeration cycle has a mechanism that heats the liquid that has absorbed the refrigerant and reseparates the refrigerant, steady operation does not occur until the liquid temperature in the generator reaches a certain temperature. There are absorption coolers that cannot immediately resume steady operation even if the temperature reaches a certain level.

For example, an absorption chiller using an absorbent whose vapor pressure is not extremely low, such as an organic absorbent or a water-ammonia system, can be installed between a generator 1 and a condenser 2, as shown in Figure 1. A rectifier 3 is installed in the generator 1.
The absorbent component mixed in the refrigerant gas stream that is heated in the refrigerant gas flow and becomes gaseous and flows toward the condenser 2 side is reduced. In this rectifier 3, for example, the absorption liquid or the like aggregated in the partial condenser 4 is dripped from the liquid disperser 5 to wet the filler 6 housed in the rectifier 3, thereby generating the generator 1. The absorbent components are removed by bringing the gas into liquid contact with the gas flow rising from the side.

However, the liquid dripped onto the filling material 6 of this rectifier is no longer supplied when the operation of the absorption chiller stops, and the liquid that had wetted the filling material 6 is also flowed down or absorbed, and the filling material 6 becomes dry. Since the rectification function of the dry filling material is small, if the absorption chiller is started to operate as it is, the performance of the rectifier will remain low for a while, and the A large amount of absorbent components flowed through the condenser 2 to the evaporator 7, resulting in a decrease in the efficiency of the absorption chiller.

The present invention, which was created in view of these points, provides an absorption liquid supply device above the rectifier of the absorption chiller, and when the absorption chiller starts operating, the temperature of the absorption liquid in the generator reaches a constant temperature, and the temperature of the absorbent liquid in the generator reaches a constant temperature. Before starting operation, a large amount of absorption liquid is temporarily dropped from the top of the rectifier to pre-wet the filling material of the rectifier, and then the operation is switched to steady-state operation. This enables a prompt transition to steady operation of the absorption chiller and improves the operating efficiency of the chiller.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 2, 1 has a heating device using a combustor 8 of kerosene, gas, etc., and absorbs a large amount of refrigerant (hereinafter referred to as concentrated liquid). 3 is a rectifier for separating absorbent components from an ascending refrigerant gas stream; This is a partial condenser in which the incoming gas stream is cooled by a heat exchanger 9 for final separation of absorbent components. 7 has a heat exchanger 10, is liquefied in a condenser 2, and is liquefied in a pressure reducing valve 1.
1 is an evaporator that applies heat to the sprayed liquid refrigerant from the heat exchanger 10 to vaporize it; 12 is a 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 13 and sprayed from the disperser 14, thereby absorbing the refrigerant gas vaporized by the evaporator 7. The evaporator 7 continuously absorbs heat from the fluid flowing through the heat exchanger 10, and supplies the heated fluid to the outside of the machine via the heat exchangers 15, 16, and 9 (operates as an absorption heating machine) or exchanges heat. This absorber is capable of supplying the cooled fluid as it flows through the absorber 10 to the outside of the machine (operating as an absorption refrigerator). The refrigerant is distributed from the liquid distributor 18 through the heat exchanger 17 to the filling material 19 below the rectifier, and flows down to the generator 1 in contact with the gas flow rising from the generator 1, where the refrigerant is separated again. .

20 is a side pipe with an on-off valve 21 that connects the suction side S of the absorption liquid pump 16 and the lower part of the generator 1, and 22 is a three-way valve disposed on the discharge side D of the absorption liquid pump 16. , 23 is a liquid sprayer whose liquid inlet is connected to the three-way valve 22 and disposed above the filler 6 of the rectifier, and the on-off valve 21 and the three-way valve 22 are
A sensor 2 that detects the temperature (or pressure) of the generator 1
4 and a controller 27 that receives signals from a sensor 26 that detects the liquid level of the absorption liquid reservoir 25 at the bottom of the absorber.
The opening/closing is controlled as described below.

In such a configuration, control at the time of starting will be explained below. When the absorption chiller starts operating by igniting the heater 8 of the generator, etc., the liquid temperature (and pressure) in the generator 1 is low, so this temperature and pressure are detected by the sensor 24 and used as input. Controller 27
In this case, the on-off valve 21 is opened, the three-way valve 22 is opened to the liquid distributor 18 side in the middle of the rectifier, and the absorption liquid is transferred to the pump 16.
Accordingly, the generator 1, the side pipe 20, the on-off valve 21,
The liquid temperature is raised while circulating a short cycle in which the liquid is returned to the generator 1 via the pump 16, heat exchanger 17, three-way valve 22, and liquid distributor 18.

In this way, when the liquid temperature in the generator 1 rises and the liquid can be delivered at the internal pressure of the generator 1, the controller 27 closes the on-off valve 21, and the absorbing liquid is pumped by the pump 16. , the short cycle returns to the generator 1 via the generator 1, heat exchanger 17, pressure reducing valve 13, absorber 12, absorption liquid pump 16, heat exchanger 17, three-way valve 22, and liquid distributor 18. Although it is further heated while being circulated, the liquid temperature is still low in this state, so the refrigerant gas flow hardly flows into the condenser 2 and causes heat loss.

In this way, the heating of the absorption liquid in the generator 1 is approximately
When the temperature (or pressure) reaches the same temperature as in the steady operating state, the controller 27 switches the three-way valve 22 based on the input from the sensor 24 so that the absorption liquid discharged from the pump 16 is transferred to the upper part of the rectifier 3. A large amount of water is discharged from the sprayer 23, and the filling material 6 is completely wetted. When the amount of liquid in the absorption liquid reservoir 25 decreases due to the dispersion of such a large amount of absorption liquid and falls below a certain level, the controller 27 controls the three-way valve 22 to close the liquid again based on the signal input from the sensor 26. Switching to the disperser 18 side, a so-called normal absorption refrigeration cycle is formed.

Figure 2 shows one configuration for smoothly performing the above control, in which the flow resistance on the liquid distribution device 23 side is made smaller than the flow resistance on the liquid distribution device 18 side, and the absorption chiller is Although the filling material 6 is easily wetted at the beginning of operation, even if the pipe 28 is connected to the disperser 18 so that the liquid disperser 23 also serves as the liquid disperser 5, the liquid disperser 23 is not particularly provided. Even if the direction of the piping 28 is adjusted so that the filling material 6 is wetted by a large amount of absorption liquid at once, the object of the present invention can be sufficiently achieved, and the on-off valve 21 is also absolutely necessary. It's not even a thing.

In this way, in the present invention, by adopting a method of making the filler wet by temporarily causing a large amount of absorption liquid to flow down from the upper part of the rectifier at the start of operation of the absorption chiller, , even if the amount of reflux liquid dripping from the partial condenser 4 to the packing material 6 decreases during steady operation, this small amount of liquid will spread over the entire packing material and rise from the generator to a sufficient wetted surface. Since it is possible to secure a wide gas-liquid contact surface with the refrigerant gas flow, unlike conventional absorption chillers of this type, it takes time for the filler to get wet even after the transition to steady operation, and separation of the absorbent components. The desired cooling and heating capacity can be achieved quickly compared to chillers that were unable to perform the necessary functions, and in the aircraft design, an excess capacity was designed to provide rectifying function beyond what was necessary. The unit can also be made smaller compared to conventional absorption chillers, which are prepared for lower efficiency.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an example of a conventional absorption chiller, and FIG. 2 is a circuit diagram showing an embodiment of an absorption chiller implementing a starting method according to the present invention. 1 - generator, 2 - condenser, 3 - rectifier, 6 - filler, 22 - three-way valve, 27 - controller.

Claims (1)

[Claims] 1. A generator for separating an absorbent component from a gas stream heated and vaporized by the generator to obtain a refrigerant gas stream, and a rectifier for reducing the absorbent component mixed in the refrigerant gas stream.
The refrigerant is separated in the condenser that cools and liquefies the refrigerant gas, the evaporator that obtains heat from the fluid outside the machine and vaporizes the liquid refrigerant, and the generator. The generator is equipped with an absorber designed to absorb water, and the generator, condenser, evaporator, absorber, etc. are connected with airtight piping, and the absorbed liquid at the bottom of the absorber is returned to the generator using a pump. In the circulation cycle of the refrigerant and absorbent, an absorption liquid supply device is provided above the rectifier, and when the temperature of the generator reaches a certain temperature, the circulation cycle of the refrigerant and absorbent is switched to a normal operation cycle. A method for starting an absorption chiller, in which a larger amount of absorption liquid than usual is flowed through the absorption liquid supply device to pre-wet the filling material of the rectifier with the absorption liquid.