JPH0419406Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] This invention relates to an absorption refrigerator.

[Conventional technology]

As shown in Figure 3, this type of absorption refrigerator consists of a high-temperature regenerator 1 into which a dilute solution is introduced and heated, and a pump tube that pumps the high-temperature dilute solution heated and boiled in the high-temperature regenerator 1. The intermediate concentrated solution separated by the separator 3 is led to the high temperature heat exchanger 5 through the intermediate downcomer pipe 4, and High temperature heat exchanger 5
The temperature of the intermediate concentrated solution is lowered by heat exchange with the dilute solution, and the lowered temperature of the intermediate concentrated solution is introduced via the intermediate liquid rising pipe 6, and the introduced intermediate concentrated solution is passed from the separator 3. a low-temperature regenerator 8 that heats the high-temperature steam by passing through a steam pipe;
The refrigerant vapor generated by heating the intermediate concentrated solution in the low-temperature regenerator 8 and the liquid refrigerant in the steam pipe 7 that has been condensed by taking heat from the intermediate concentrated solution are introduced, and are transferred into the cooling water coil 9. a condenser 10 that is cooled and condensed by cooling water flowing through the condenser 1;
After the refrigerant condensed at
an evaporator 15 that is guided by a refrigerant dripper 13 and distributed over a chilled water coil 14 for evaporation;
Connecting pipe 1 for dropping the concentrated solution from the low-temperature regenerator 8
6 to a low-temperature heat exchanger 17, the heat exchanger 17 lowers the temperature of the concentrated solution, and the cooled concentrated solution is introduced through a concentrated solution inlet pipe 18 and sprayed onto the cooling water coil 9. an absorber 19 which absorbs the refrigerant vapor evaporated in the evaporator 15 to form a dilute solution and removes the absorption heat generated during absorption by the cooling water flowing in the cooling water coil 9; A solution circulation pump 21 that sends the dilute solution in the container 19 to the high temperature regenerator 1 via a dilute solution pipe 20 having heat exchangers 17 and 5, and a temperature detector 30 that detects the refrigerant temperature in the refrigerant dripper 13. , a control device 31 that compares the detection signal from the temperature detector 30 with a set temperature value to form a control signal, and a refrigerant solenoid valve 3 that opens and closes according to the control signal from the control device 31.
2, and the bypass pipe 33 is connected between the refrigerant inflow pipe 12 and the concentrated solution inflow pipe 18.

According to such an absorption refrigerator, when performing cooling operation at a low cooling water temperature, the temperature of the refrigerant provided at the upper part of the evaporator 15 is detected by the temperature detector 30, and this detected signal is detected. The control device 31 compares this with a set temperature value set at a temperature slightly higher than the temperature at which the refrigerant freezes, and a control signal obtained from the result is used to control the concentration solution inflow pipe 18 and the refrigerant inflow pipe 1.
The refrigerant electrode valve 32 provided in the bypass pipe 33 that connects the refrigerant and the refrigerant is set to the "open" state, and the concentrated solution is allowed to flow into the refrigerant inflow pipe 12, and the dilution heat generated by mixing the refrigerant and the concentrated solution and the refrigerant The freezing of the refrigerant at low vapor pressure is prevented by lowering the evaporation temperature of the refrigerant.

[Problem that the invention attempts to solve]

However, in such conventional technology, in order to lower the freezing temperature of the refrigerant, in other words, to lower the evaporation pressure of the refrigerant, a concentrated solution is flowed into the refrigerant liquid to form a solution-mixed refrigerant liquid. Yes, but
If this solution mixed refrigerant liquid is allowed to flow down while being evaporated on the surface of the evaporator 15, the refrigerant liquid portion of this solution mixed refrigerant liquid will be prioritized and evaporated.
Therefore, as the evaporation phenomenon progresses, the solution concentration in the mixed refrigerant solution gradually increases, and the evaporation pressure decreases compared to the initial stage of dropping, and evaporation becomes impossible with the vapor pressure in the atmosphere of the evaporator 15. Become.

In other words, in order to sufficiently evaporate the solution-mixed refrigerant liquid, although it is necessary to lower the solution concentration of the solution-mixed refrigerant at the time of dropping, the evaporation temperature increases, making the freezing phenomenon more likely to occur. Conversely, if emphasis is placed on preventing freezing, sufficient evaporation of the solution-mixed refrigerant becomes impossible.

Therefore, the degree of mixing must be determined from the viewpoints of freezing ability due to evaporation and prevention of freezing, and there has been a problem in that conventional techniques cannot satisfy both conditions.

This invention was made in view of the above points, and the purpose is to provide an absorption refrigerator that can prevent freezing and exhibit a refrigerating capacity at the same time as the normal cooling water temperature.

[Tasks to solve problems]

This idea consists of a high-temperature regenerator that heats the dilute solution,
a separator that separates the high-temperature dilute solution from the high-temperature regenerator into high-temperature steam and an intermediate concentrated solution; and a high-temperature heat exchanger that exchanges heat between the intermediate concentrated solution from the separator and the dilute solution introduced into the high-temperature regenerator. a low-temperature regenerator that heats an intermediate concentrated solution from the high-temperature heat exchanger with high-temperature steam from the separator to produce steam and a high-temperature concentrated solution; A condenser that cools the steam and the steam used for heating and converts it into a liquid refrigerant, and a high-temperature concentrated solution from the low-temperature regenerator and a dilute solution introduced into the high-temperature regenerator. A low-temperature heat exchanger for exchanging liquid refrigerant, an evaporator for evaporating the liquid refrigerant from the condenser, and the vapor refrigerant evaporated by the evaporator being absorbed into a concentrated solution introduced through the low-temperature heat exchanger to form a dilute solution. an absorber;
In an absorption refrigerator comprising a solution circulation pump that sends a dilute solution from the absorber to a high temperature regenerator via a high temperature heat exchanger and a low temperature heat exchanger, the high temperature heat exchanger and/or the low temperature the pressure and temperature of at least one of the absorber and the evaporator in order to bypass the intermediate concentrated solution or the hot concentrated solution introduced into the heat exchanger from the high temperature heat exchanger and/or the low temperature heat exchanger; A detection control means is provided for detecting either of the above and generating an opening/closing control signal depending on whether or not this detection signal exceeds a predetermined set value. A bypass pipe is provided which communicates with the inlet side of the intermediate concentrated solution or the high temperature concentrated solution and the outlet side of the concentrated solution from the low temperature heat exchanger, and the bypass pipe is operable by the opening/closing control signal. It is characterized by being equipped with a solenoid valve.

The bypass pipe is provided in communication with the introduction side of the high temperature concentrated solution to the low temperature heat exchanger and the outlet side of the high temperature concentrated solution from the low temperature heat exchanger, or the bypass pipe is connected to the high temperature It is desirable that the intermediate concentrated solution be provided in communication with the introduction side of the intermediate concentrated solution into the high temperature heat exchanger and the output side of the concentrated solution from the low temperature heat exchanger.

[Effect]

If the cooling water temperature becomes low during cooling operation,
The temperature of the refrigerant or the pressure of the absorber or evaporator is detected by the detection control means, and the detection signal is compared with a set value set slightly higher than the freezing temperature of the refrigerant, and when the temperature exceeds this, an open control signal is generated. is generated by the detection control means. The low-temperature heat exchange is bypassed by a bypass pipe provided with a solenoid valve that is opened by the opening control means from the detection control means, and the concentrated solution that is not subjected to heat exchange flows into the concentrated solution that has undergone heat exchange. Then, the temperature of the concentrated solution supplied to the absorber is increased by the amount of inflow of the concentrated solution before heat exchange, so that it will not freeze even if it is supplied to the absorber.

In the above description, the bypass pipe is connected to a part that bypasses the low-temperature heat exchanger, but of course it may be a part that bypasses both heat exchangers.

〔Example〕

This invention will be explained below based on the drawings. FIG. 1 is a block diagram showing a first embodiment of this invention. In FIG. 1, the same components as those shown in FIG. 2 are denoted by the same reference numerals, and explanations of the structure and the like will be omitted.

The configuration shown in FIG. 1 differs from the configuration shown in FIG. 3 by eliminating the refrigerant solenoid valve 32 and the bypass pipe 33 provided with the refrigerant solenoid valve 32, and by converting the concentrated solution concentrated in the low-temperature regenerator 8 to low-temperature heat. Concentrated solution-heat exchange connecting pipe 16 leading to exchanger 17 and low temperature heat exchanger 1
A bypass pipe 41 is provided that connects the concentrated solution inflow pipe 18 that guides the heat-exchanged concentrated solution from the absorber 19 to the absorber 19. A concentrated solution electromagnetic valve 42 is provided which is inputted into the control device 31 and opened and closed by an opening/closing control signal from the control device 31. Note that the detection control means is composed of a detector 30 and a control device 31.

The fabrication of the embodiment configured as described above will be explained.

If the cooling water temperature becomes low during cooling operation,
A temperature detector 30 detects the temperature of the refrigerant in the refrigerant dripper 13 provided above the evaporator 15 . The detection signal detected by the detector 30 is taken into the control device 31 and compared with a set value set at a temperature slightly higher than the temperature at which the refrigerant becomes frozen. When the detection signal is equal to or less than the set value, the control device 31 outputs a control signal for opening, and the concentrated solution solenoid valve 42 provided in the concentrated solution bypass pipe 41 is set to the "open" state. , the high temperature concentrated solution before heat exchange is allowed to flow into the low temperature concentrated solution after heat exchange.

Then, the temperature of the concentrated solution supplied to the absorber 19 is increased by the amount of inflow of the concentrated solution before heat exchange, so even if it is dropped into the absorber 19 and cooled, it will not reach the freezing temperature as in the conventional case. It becomes unnecessary. Therefore, the vapor pressure of this concentrated solution is such that the concentrated solution does not bypass the heat exchanger 1 as in this invention.
It becomes higher than the vapor pressure of the concentrated solution heat exchanged in step 7. Therefore, the vapor pressure of the evaporator 15 will not drop below the freezing temperature of the refrigerant, making it possible to prevent the refrigerant from freezing.

FIG. 2 is a block diagram showing a second embodiment of this invention.

In FIG. 2, the same components as those in FIG. 1 are designated by the same reference numerals, and their explanations will be omitted.

The second embodiment shown in FIG. 2 differs from the first embodiment in that a bypass pipe 41 provided with an electromagnetic valve 42 is connected between the intermediate liquid down pipe 4 and the concentrated solution inflow pipe 18.

Even with this configuration, the same effects as in the first embodiment can be obtained.

In both the first and second embodiments, the temperature detector 30 measures the temperature of the concentrated solution flowing into the absorber 19, etc.
The installation location does not matter as long as it can detect when the pressure of the absorber or evaporator has decreased.

Further, in each of the above embodiments, the pressure drop was detected by temperature, but the pressure may be directly detected.

[Effect of idea]

As explained above, according to this idea,
Since all of the refrigerant liquid obtained in the condenser can be evaporated in the evaporator, sufficient refrigerating capacity can be obtained and the refrigerant can be reliably prevented from freezing.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the first embodiment of this invention.
FIG. 2 is a block diagram showing a second embodiment of this invention, and FIG. 3 is a block diagram showing a conventional technique. 1... High temperature regenerator, 2... Lifting liquid pipe, 3... Separator, 4... Intermediate liquid downfall pipe, 5... High temperature heat exchanger,
6... Intermediate liquid up pipe, 7... Evaporation pipe, 8... Low temperature regenerator, 10... Condenser, 12... Refrigerant inflow pipe,
13... Refrigerant dripper, 15... Evaporator, 16...
Concentrated solution-heat exchanger freezing tube, 17... Low temperature heat exchanger, 18... Concentrated solution inflow tube, 19... Absorber, 2
0... Dilute solution tube, 30... Temperature detector, 31...
Control device, 41... Bypass pipe, 42... Solenoid valve.

Claims (1)

[Claims for Utility Model Registration] (1) A high-temperature regenerator that heats a dilute solution, a separator that separates the high-temperature dilute solution from the high-temperature regenerator into high-temperature steam and an intermediate concentrated solution, and a a high-temperature heat exchanger for exchanging heat between the intermediate concentrated solution and the dilute solution introduced into the high-temperature regenerator, and heating the intermediate concentrated solution from the high-temperature heat exchanger with high-temperature steam from the separator to generate steam and high-temperature solution. a low-temperature regenerator for converting into a concentrated solution, and a condenser for converting into a liquid refrigerant by introducing steam heated by high-temperature steam in the low-temperature regenerator and steam that has been heated and cooling them. , a low-temperature heat exchanger that exchanges heat between the high-temperature concentrated solution from the low-temperature regenerator and the dilute solution introduced into the high-temperature regenerator; an evaporator that evaporates the liquid refrigerant from the condenser; An absorber that absorbs vapor refrigerant into a concentrated solution introduced through a low-temperature heat exchanger to form a dilute solution, and an absorber that supplies the dilute solution from the absorber to a high-temperature regenerator through a low-temperature heat exchanger and a high-temperature heat exchanger. In an absorption refrigerating machine, the intermediate concentrated solution or the high temperature concentrated solution introduced into the high temperature heat exchanger and/or the low temperature heat exchanger is /or detecting the pressure and temperature of at least one of the absorber and evaporator to bypass the low-temperature heat exchanger; and opening and closing depending on whether or not this detection signal exceeds a predetermined set value. a detection control means for generating a control signal; and an introduction side of the intermediate concentrated solution or the high temperature concentrated solution to the high temperature heat exchanger or the low temperature heat exchanger and an output side of the concentrated solution from the low temperature exchanger. 1. An absorption refrigerating machine characterized in that a bypass pipe is provided which communicates with each other, and a solenoid valve operable by the opening/closing control signal is disposed in the bypass pipe. (2) A practical use characterized in that the bypass pipe is provided in communication with an inlet side of the high temperature concentrated solution to the low temperature heat exchanger and an outlet side of the concentrated solution from the low temperature heat exchanger, respectively. An absorption chiller according to claim 1 of the patent registration claim. (3) A practical use characterized in that the bypass pipe is provided in communication with an inlet side of the intermediate concentrated solution to the high temperature heat exchanger and an outlet side of the concentrated solution from the low temperature heat exchanger, respectively. An absorption chiller according to claim 1 of the patent registration claim.