JPH01266476A - Absorption refrigerator - Google Patents

Abstract

PURPOSE:To cool down vapor for heating a low temperature generator to a saturation temperature to convert it into saturated vapor, to improve heat exchange performance, and to minimize the low temperature generator by spraying a refrigerant liquid condensed by a heat exchanger for heating within the low temperature generator through a sprayer. CONSTITUTION:Refrigerant vapor separated by a high temperature generator 1 passes through the inside of a cooling chamber 21 and is sent into a heat exchanger 23, and then, said refrigerant vapor is condensed by exchanging heat with an absorption liquid within a low temperature generator 3. A refrigerant liquid within the heat exchanger 23 flows, by its own weight, into a sprayer 22 provided at a lower position than the heat exchanger 23. The sprayer 22 sprays the refrigerant liquid to superheated vapor passing through the inside of the cooling chamber 21. A portion of the refrigerant liquid is evaporated by absorbing heat from the superheated vapor in its direct contact therewith. The temperature of the superheated vapor is lowered down to a saturation temperature by this evaporation of the refrigerant liquid or the spray thereof. The refrigerant liquid accumulated in the lower part of the cooling chamber 21 is pushed up through the inside of a tube 27 by the difference between the pressure in the cooling chamber 21 and that in a condenser 4 is fed into the condenser 4.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a dual-effect absorption refrigerator, and more particularly to a device for adjusting the temperature of steam for heating an absorption liquid in a low-temperature generator.

(b) Conventional technology Conventionally, in this type of dual-effect absorption refrigerating machine, a high-temperature generator, a low-temperature generator that heats and separates the refrigerant in the absorbed [intermediate] liquid using the refrigerant vapor from the high-temperature generator, and a condensing A refrigeration cycle is constructed by connecting a container, an absorber, etc. with piping [
For example, see Japanese Patent Publication No. 60-40788].

(c) Problems to be Solved by the Invention However, this type of dual-effect absorption refrigerator has the following problems. The refrigerant vapor sent from the high-temperature generator to the low-temperature generator includes superheated steam and saturated steam heated above the saturation temperature, and the superheated steam exchanges heat with the absorption liquid in the low-temperature generator and becomes saturated. It turns into steam,
Alternatively, the saturated vapor exchanges heat with the absorption liquid and condenses.

The heat transfer coefficient of the above-mentioned hot steam is about two orders of magnitude smaller than that of saturated steam. Since superheated steam with this very small heat transfer coefficient exchanges heat with the absorption liquid, the heat exchange performance is poor and the temperature is low. A problem has arisen in that the heat transfer area of the generator has to become large (the low-temperature generator has no choice but to become large).゛The present invention has been made in view of the problems of the prior art described above, and aims to improve the heat exchange performance by cooling the steam that heats the low-temperature generator to the saturated temperature and converting it into saturated steam. The present invention provides a dual-effect absorption refrigerator whose generator is downsized.

(d) Means for solving the problems In order to solve the problems of the prior art mentioned above, the present invention provides the following:
In the absorption refrigerator, a cooling chamber having a lid made of refrigerant liquid dispersion on the upper part is provided at a lower position than the heat exchanger, and a path from the gas phase part of the high temperature generator to the condenser is connected to the gas phase part of the high temperature generator. and the cooling chamber; a pipe line connecting the cooling chamber and the heating heat exchanger; a heating heat exchanger; and a refrigerant for the heating heat exchanger. It consists of a pipe line that sends the liquid to the spraying device, and a pipe line that connects the lower part of the cooling chamber and the condenser and has a mechanism to maintain a pressure difference in the middle.

(E) Function During operation of the absorption refrigerator of the present invention, refrigerant vapor separated from the absorption liquid in the high-temperature generator is condensed in the heating heat exchanger in the low-temperature generator to become a refrigerant liquid. This refrigerant liquid flows under its own weight through the pipes to the refrigerant liquid distribution device.

The refrigerant liquid is distributed from the distribution device to the refrigerant (superheated) vapor passing through the cooling chamber. By this dispersion, the superheated steam is cooled to the saturation temperature (or close to the saturation temperature), and this cooled steam, that is, saturated steam (or superheated steam whose temperature is slightly higher than the saturation temperature) is used as the heating heat source for the heat exchanger. used as. The refrigerant liquid in the lower part of the cooling chamber is sent to the condenser due to the pressure difference between the cooling chamber and the condenser.

(f) Example An absorption refrigerating machine which is an example of the present invention is shown in the drawings, and will be described below with reference to the drawings. (1) is a high-temperature generator that heats a dilute liquid and separates the refrigerant as vapor; (2) is a heating steam pipe line that supplies steam as a heating heat source for this high-temperature generator; and (3) is a high-temperature generator ( 1) is a low temperature generator that further heats the intermediate liquid and separates the refrigerant as vapor; (4) is a condenser into which the condensed refrigerant liquid flows; ), (7) and (8) are the refrigerant pipes for sending to the evaporator (
6) refrigerant circulation pipes and refrigerant pumps for dispersing the unevaporated refrigerant in the water cooler (9) again, (10) and (11)
) is equipped with a tank liquid pipe and a solution pump for sending the diluted liquid in the absorber (12) to the high temperature generator (1), and (13) is equipped with a high temperature heat exchanger (14), and the high temperature generator (1 ) intermediate liquid pipe for conveying intermediate liquid from ) to the low temperature generator (3), (15)
is equipped with a low temperature heat exchanger (16) and a low temperature generator (3
) for sending the concentrated liquid from the absorber (12) to the absorber (12), (
17) is a cold water pipe having the water cooler (9), and (18) is a cooling water pipe having the cooler (19) (2G).

(21) has a tray or siphon [not shown] on the top.
It has a dispersion device (22) consisting of a low temperature generator (
The cooling chamber (24) is located at a lower position than the heat exchanger (23) in the cooling chamber (24) and the high temperature generator (
(25) is a steam pipe connecting the gas phase part of the cooling chamber (21) and the upper part of the heat exchanger (23); (26) is the steam pipe connecting the gas phase part of the cooling chamber (21) with the upper part of the heat exchanger (23); A refrigerant liquid pipe (2) connecting the lower part of the exchanger (23) and the distribution device (22);
7) is a refrigerant liquid delivery pipe that connects the lower part of the cooling chamber (21) and the condenser (4), and (28) is an orifice provided in this pipe as a mechanism to maintain the pressure difference. .

As a mechanism for maintaining the pressure difference, a capillary may be provided, the tube (27) may be made thin, or a steam trap may be provided.

The structure of the present invention has been described above, and next, it will be explained why superheated steam is less suitable as a heating heat source for a low temperature generator than saturated steam.

The heat transfer coefficients of superheated steam in the steam pipe (18), saturated steam in the heating heat exchanger (3), and intermediate liquid in the low-temperature generator (2) are α□, α35. α, then 60 each
．． 8000.1000 (unit: kcal/m”h℃)
That's about it.

And the heat transfer rate between superheated steam and intermediate liquid is 1/□
゛ is given by =1/α□+1/α, +δ/in, but the third term on the right side is extremely small compared to the first and second terms on the right side, so the heat transfer rate 1csst is α□・αA/(α□ It can be approximated by +αc.The heat transfer rate XSS between the saturated steam and the intermediate liquid can be similarly calculated by the heat transfer rate KsS−α3.・α.

/(α, S−αc).For these heat transfer rates, □.

When calculating K2S, each is 57,889 (unit: k
cal/m"h"c).

In this way, the heat transfer coefficient α□ of superheated steam is extremely small compared to the heat transfer coefficient α of the intermediate liquid that exchanges heat, and the heat transfer coefficient α,S of saturated steam, and therefore the heat transfer coefficient between the superheated steam and intermediate liquid is Passage rate! css+ is very small compared to the heat transfer rate Ls between the saturated steam and the intermediate liquid. Heat transfer rate □ is heat transfer rate XS
Because it is very small compared to S, the heat of superheated steam is less likely to be transferred to the intermediate liquid than the heat of saturated steam.In this way, even though the temperature of superheated steam is higher than that of saturated steam, it is difficult for heat to be transferred to the intermediate liquid, so it is lower in temperature. This means that it is not suitable as a heating heat source for the generator (2).

Next, the operation of the present invention will be explained. High temperature generator (1
) The refrigerant vapor (this vapor contains heating vapor) is sent through the cooling chamber (21) into the heat exchanger (23) and is mixed with the absorption liquid in the low temperature generator (3). Condenses through heat exchange. The refrigerant liquid in the heat exchanger (23) is disposed at a lower position than the heat exchanger (23) due to its own weight! Flows to (22). The spraying device (22) has a cooling chamber (2
1) Sprinkle refrigerant liquid onto the superheated steam passing through. A portion of the refrigerant liquid absorbs heat from the superheated vapor through direct contact and evaporates, and the evaporation of this refrigerant liquid or the dispersion of the refrigerant liquid lowers the superheated vapor to the saturation temperature (or superheated vapor slightly higher than the saturation temperature). . The refrigerant liquid accumulated in the lower part of the cooling chamber (21) is pushed up inside the pipe (27) by the pressure difference between the pressure inside the cooling chamber (21) and the inside of the condenser (4) of 650 mmHg. will be sent to.

In the present invention, since superheated steam with a low heat transfer coefficient is cooled by direct contact with a refrigerant liquid, superheated steam can be more effectively cooled to saturated steam (or heated steam whose temperature is slightly higher than the saturated temperature). In addition, when obtaining saturated steam by cooling superheated steam from the high temperature generator (1) with cooling water passing through a heat exchanger formed outside the steam pipes (24) and (25), the superheated steam is Since there is a risk of cooling (condensation), a device is required to control the flow rate of cooling water according to the amount of superheated steam, but in the present invention, there is no control.
For example, it does not require a device to control the amount of sprayed refrigerant liquid, nor does it require power to circulate the refrigerant liquid.

In addition, in the present invention, since the superheated steam is cooled by the refrigerant liquid in the heat exchanger (23), this refrigerant liquid is sent to the condenser (4) at approximately the same temperature, and the refrigerant liquid in the condenser (4) is When the superheated vapor is cooled with a refrigerant liquid or a refrigerant liquid in the evaporator (6), it has to be cooled again to the refrigerant liquid temperature at the original location, resulting in heat loss, but in the case of the present invention, the above-mentioned It has the advantage of no heat loss and no effect on the refrigerant circulation path.

(G) Effects of the Invention In the absorption refrigerator of the present invention, the steam used as the heating heat source for the low-temperature generator is converted into saturated steam [or steam whose temperature is slightly higher than the saturated temperature], so heat exchange in the low-temperature generator is achieved. This has the effect of increasing the amount of heat and making it possible to downsize the low-temperature generator.

[Brief explanation of the drawing]

The figure is a schematic structural explanatory diagram of an absorption refrigerator that is an embodiment of the present invention. (1)...High temperature generator, (3)...Low temperature generator,
(4)...Condenser, (21)...Cooling chamber, (
22)...Spreading device, (23)...Heat exchanger, (
24)...Steam pipe, (25)...Steam pipe, (2
6)...tube, (27)...tube, (28)...orifice.

Claims (1)

[Claims] (1) In an absorption refrigerating machine in which a refrigeration cycle is constructed by connecting a high-temperature generator, a heating heat exchanger that heats the absorption liquid in a low-temperature generator, a condenser, an evaporator, etc. with piping, a refrigerant liquid dispersion device is installed at the top. A cooling chamber having a cooling chamber is provided at a lower position than the heat exchanger, and a path from the gas phase portion of the high temperature generator to the condenser is connected to the gas phase portion of the high temperature generator and the cooling chamber; the cooling chamber; a pipe line connecting the cooling room and the heating heat exchanger; a heating heat exchanger; a pipe line for sending the refrigerant liquid of the heating heat exchanger to the dispersion device; An absorption refrigerator characterized by comprising a conduit connecting the lower part of a cooling chamber and a condenser and having a mechanism for maintaining a pressure difference in the middle.