JP3236721B2 - Regenerator for absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerator used for an absorption refrigerator, and more particularly to a regenerator using a plate-fin type heat exchanger.

[0002]

2. Description of the Related Art First, a schematic overall configuration of an absorption refrigerator is shown in FIG.
This will be described with reference to the block diagram of FIG. The absorption refrigerating machine heats the solution (for example, lithium bromide) with a heating means 7 so as to enhance the refrigerant absorption capacity of the aqueous solution (for example, lithium bromide) aqueous solution (hereinafter, simply referred to as a solution) having an excellent ability to absorb the refrigerant (for example, water). A regenerator 1 for heating and condensing, a condenser 2 for introducing vapor (refrigerant) separated from a solution in the regenerator 1 and cooling it to liquefy it, and a refrigerant liquefied by the condenser 2 An evaporator 3 that introduces and evaporates (vaporizes) under low pressure, and an absorber 4 that contains a solution (concentrated solution) concentrated in the regenerator 1 to absorb the vapor generated in the evaporator 3. A dilute solution reservoir 5 for storing a solution (dilute solution) diluted by absorbing the vapor in the absorber 4.
And a solution pump 6 for feeding the diluted solution to the regenerator 1 again for concentration.

One of the functions of an absorption refrigerator is a cooling function utilizing latent heat by evaporating (vaporizing) a refrigerant in an evaporator. In one example, when the cold water of about 12 ° C. passes through the evaporator 3 via the pipe 8 and reaches the evaporator outlet, it is cooled to about 7 ° C.

FIG. 3 is a During diagram showing the relationship between the temperature and the pressure in each part of the absorption refrigerator shown in FIG. 3 in FIG. 3 correspond to FIG.

FIG. 2 shows an example of a single-effect absorption refrigerator having one regenerator. However, a double-effect absorption refrigerator using two regenerators of a high-temperature regenerator 1a and a low-temperature regenerator 1b is shown. FIG. 4 shows an overall configuration of the refrigerator, and FIG. 5 shows a During diagram thereof. 5 correspond to FIG.

[0006] The vapor absorption capacity of an aqueous solution of lithium bromide is stronger as the solution temperature is lower and as the concentration is higher. Absorber 4
When the refrigerant vapor is absorbed in the solution, the heat of absorption substantially equal to the heat of condensation in the condenser 2 is added to the solution, so that the solution temperature increases and the concentration also decreases. Therefore, a cooling pipe 9 as a heat transfer pipe is provided in the absorber 4, and the absorption heat is removed from the solution by the cooling water flowing inside.

The conventional regenerators used in the above absorption refrigerators include a full type in which a plurality of heating pipes are continuously filled with a solution in a container in which a plurality of heating pipes are arranged close to each other. A plurality of solution introduction tubes having a plurality of downwardly drilled holes are arranged above the container, and the solution flows down to a plurality of heating pipes arranged below the solution introduction tubes. A falling liquid film type as described above is known.

As a conventional once-through regenerator, as shown in FIG. 6, there is a regenerator in which a pipe is spirally wound so that its axis is substantially vertical. The helical pipe 22 is installed in the passage 23 of the combustion gas as the heating fluid HF, and the dilute solution WS flows into the pipe with the lower part of the helical pipe 22 as an inlet and the upper part as an outlet to make the dilute solution WS circulate. While heating. The separation between the refrigerant vapor VR and the concentrated solution CS is performed after the outlet.

[0009]

Incidentally, the above-mentioned conventional liquid-filled regenerator is suitable in terms of uniform and stable heating of the solution, but the starting time is long because the amount of the solution is extremely large. In addition, there is a problem that the response to the load fluctuation is slow, the separation of the dilute solution and the concentrated solution is difficult, and the dilute solution is mixed into the concentrated solution.

In addition, the falling liquid film type regenerator requires a smaller amount of solution as compared with the full liquid type regenerator, and therefore responds quickly to load fluctuations. It is important to drop the solution evenly into the group,
A separate device is required for this, and there is a problem in making the device compact.

Furthermore, in a conventional once-through regenerator formed by spirally winding a single pipe, the solution is deflected in the pipe due to the effect of centrifugal force, and local heating is likely to occur. Causes corrosion. In addition, it is necessary to increase the volume of the helical pipe in order to secure a heat transfer area, and the entire device becomes large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and an object of the present invention is to uniformly dilute a dilute solution by a heating and heat exchange system that can effectively use low-temperature exhaust heat. An object of the present invention is to provide a compact regenerator that can be heated and can efficiently separate a refrigerant vapor and a concentrated solution.

[0013]

In order to achieve the above object, according to the main aspect of the present invention, a housing is formed by combining front, rear, left and right side plates that are substantially vertically erecting, and these side plates. And a top plate and a bottom plate respectively disposed at the upper and lower ends of the side plate, and integrally fixed to a lower inner wall of the side plate at a predetermined distance from the bottom plate so as to form a lower outer header. A lower flat sidebar, and an upper flat sidebar integrally fixed to an upper inner wall of the side plate at a predetermined distance from the top plate so as to form an upper outer header;
A plurality of sets of tube plates spaced apart from each other within the housing and erected through the lower and upper flat sidebars, each forming a narrow internal space extending vertically, and each internal space is Openings communicating with the lower and upper outer headers are provided at lower and upper ends, respectively, and between the lower and upper flat sidebars, the interior of the housing is liquid-tight, and the internal space in the upper outer header is provided. A baffle plate for gas-liquid separation provided above the upper end opening of the tube plate, and an outer wall surface of the tube plate located between the lower and upper flat side bars. Heat transfer fins each having a passage formed therein, wherein the dilute solution is provided with the lower outer head. And the heating fluid flows from the upper side to the lower side along the outer wall surface of each tube plate between the upper and lower flat side bars while contacting the heat transfer fins. The dilute solution flows in and is heated by the heat of the heating fluid transmitted through the heat transfer fins and the wall surface of the tube plate while the dilute solution rises along the internal space. It becomes a gas-liquid two-phase, further rises and flows out from the upper end opening of the internal space into the upper outer header, and the concentrated solution is separated from the refrigerant vapor by the baffle plate and collected. A regenerator for an absorption refrigerator is provided.

According to another aspect of the present invention, there is provided the regenerator for an absorption refrigerator according to the main aspect, wherein the inner space of each of the plurality of tube plates is also in contact with the inner side surface of the tube plate. A regenerator for an absorption refrigerator having a heat transfer fin is provided.

According to still another aspect of the present invention, there is provided a regenerator for an absorption refrigerator, wherein a heating fluid is caused to flow in a countercurrent to a dilute solution.

[0016]

In the flow-through type regenerator using the heat transfer fin type heat exchanger of the present invention, the dilute solution introduced into the lower outer header formed at the lower portion of the housing of the regenerator includes a plurality of dilute solutions provided inside the housing. While ascending along the inner space formed in each of the tube plates, the tube plate is heated by an effective heat exchange with a heating fluid flowing from the upper side to the lower side inside the housing outside the tube plate, and the refrigerant vapor and the concentrated solution And flows out into the upper outer header at the upper end of the housing. In the upper outer header, the concentrated solution and the refrigerant vapor are efficiently separated by the baffle plate. After separation, the refrigerant vapor is delivered to a condenser, while the concentrated solution is delivered to an absorber.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the accompanying drawings (FIG. 1).

The regenerator 1 according to the present invention comprises side plates 11 standing up, down, left and right to form a housing thereof.
And a top plate 12 and a bottom plate 13 fixed to the upper and lower ends of the side plates 11, respectively.

The lower and upper flat side bars 14 and 1 which are substantially parallel to the bottom plate 13 and the top plate 12, respectively, are spaced apart from the bottom plate 13 and the top plate 12 by predetermined spaces, respectively, on the lower and upper inner side wall surfaces of each side plate 11.
5 are integrally fixed. Thereby, the lower outer header 1 into which the dilute solution WS of the refrigerant absorbing solution is introduced between the bottom plate 13 and the lower flat side bar 14.
6, and an upper outer header 17 from which the concentrated solution CS and the refrigerant vapor VR flow out are formed between the top plate 12 and the upper flat side bar 15, respectively.

In the housing, a plurality of spaces are formed at intervals from each other, and are vertically erected through the lower and upper flat side bars 14 and 15, respectively, to form narrow internal spaces 18a each extending vertically. A tube plate 18 is provided. Each of these internal spaces 18a has an opening at its lower end and upper end,
Each lower end opening (not shown) communicates with the lower outer header 16 and each upper end opening communicates with the upper outer header 17, respectively.
Between 15 and 15, the inside of the housing is made liquid-tight.

In the upper outer header 17, baffle plates 20 are provided so as to be located above the internal spaces 18a of the respective tube plates 18. A hole 12a for sending the refrigerant vapor VR is formed in a central portion of the top plate 12 corresponding to the baffle plate 20. In addition, the upper flat side bar 15 is provided so as to be slightly inclined downward toward an outlet (not shown) in order to facilitate the recovery of the concentrated solution CS.

Further, a heat transfer fin 19a is provided on each outer wall surface 18b of each tube plate 18 sandwiched between the lower and upper flat side bars 14 and 15, so as to come into contact therewith. This heat transfer fin 19a
A plate fin obtained by bending a metal plate in a vertical direction in a zigzag manner is preferably used for the purpose of reinforcing the tube plate 18 and transferring heat, but is not limited thereto. An inflow passage 21a for a heating fluid HF such as hot water is formed between an upper end of the heat transfer fin 19a and the upper flat side bar 15, and a heating passage is formed between a lower end of the heat transfer fin 19a and the lower flat side bar 14. An outflow passage 21b for the fluid HF is formed.

Still more preferably, as shown in FIG.
Heat transfer fins 19b are also provided in the respective internal spaces 18a of the tube plates 18 so as to contact the inner wall surfaces of the tube plates 18. Thereby, heat transfer (heat exchange) from the heating fluid outside the tube plate 18 to the dilute solution WS inside the tube plate 18 is performed more efficiently, and the rigidity of the tube plate 18 is further increased.

Next, the operation of the embodiment having the above configuration will be described.

The dilute solution WS introduced into the lower outer header 16 passes through the lower end opening of each tube plate 18 and the respective internal space 18 of the tube plate 18.
a, and flows upward from below in each internal space 18a. Thereafter, while the dilute solution WS rises along the internal space 18a, the lower and upper flat side bars 1
4 and 15 introduced into the housing and the inflow passage 2
1a → the heat transfer fins 19a → the heat of the heating fluid sequentially flowing through the outflow passage 21b is effectively heated by being transferred to the dilute solution WS via the heat transfer fins 19a, the side walls of the tube plate 18 and the heat transfer fins 19b. As a result, a gas-liquid two-phase flow of the refrigerant vapor VR and the concentrated solution CS gradually increases, and further rises along the internal space 18a. The high-temperature refrigerant vapor VR and the concentrated solution CS that have been heated flow out into the upper outer header 17 from the upper end opening of the internal space 18a. Refrigerant vapor V flowing into upper outer header 17
R once hits the baffle plate 20, passes through the side of the baffle plate 20, and is delivered to an evaporator (not shown) through a hole 12 a formed in the top plate 12. On the other hand, the concentrated solution CS is efficiently separated from the refrigerant vapor VR after hitting the baffle plate 20, falls on the upper surface of the upper flat side bar 15 inclined downward toward the outlet, flows on the upper surface, and flows through the absorber. (Not shown).

As the heating fluid HF, in addition to the above-mentioned hot water, heating steam, high-temperature gas and the like can be used.

When hot water is used as the heating fluid HF, it is necessary to flow hot water so as to be countercurrent to the diluted solution WS which is the fluid to be heated. This is because the temperature difference between the warm water and the dilute solution side is small, and the temperature decreases rapidly due to heat exchange.

Even in the case of the heated steam, the heated steam is made to flow countercurrent to the dilute solution WS because it is necessary to remove the condensate of the steam.

In the case of a high-temperature gas, since the temperature difference between the high-temperature gas and the dilute solution WS is large, the flow may be any of a countercurrent flow, a cocurrent flow, and a crossflow with respect to the dilute solution WS.

[0030]

As is apparent from the above description, according to the present invention, the flow of the heating fluid with respect to the dilute solution is made to flow countercurrently,
The adoption of the once-through plate fin heat exchanger has the following effects. (1) Since the heat transfer area per unit volume is large,
Low temperature exhaust heat such as steam can be effectively used. (2) Efficient separation of refrigerant vapor and concentrated solution is achieved by improved flow patterns and upper outer header. (3) The heat exchange required for raising the temperature related to the concentration of the absorbing solution (dilute solution) is made uniform and effective. (4) The size can be reduced without reducing the rigidity. (5) The cooling capacity can be improved.

[Brief description of the drawings]

FIG. 1 is a partially omitted schematic perspective view showing an embodiment of the present invention.

FIG. 2 is a block diagram showing a general overall configuration of a single-effect absorption refrigerator.

FIG. 3 is a During diagram relating to the absorption refrigerator illustrated in FIG. 2;

FIG. 4 is a block diagram showing a general overall configuration of a double effect absorption refrigerator.

FIG. 5 is a During diagram relating to the absorption refrigerator shown in FIG. 3;

FIG. 6 is a schematic perspective view showing an example of a conventional once-through regenerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Regenerator 2 Condenser 3 Evaporator 4 Absorber 5 Dilute solution reservoir 6 Solution pump 7 Heating fluid 8 Piping 9 Cooling piping 11 Side plate 12 Top plate 13 Bottom plate 14 Lower flat side bar 15 Upper flat side bar 16 Lower outer header Reference Signs List 17 upper outer header 18 tube plate 18a inner space 18b outer side wall 19a heat transfer fin 19b heat transfer fin 20 baffle plate 21a heating fluid inflow passage 21b heating fluid outflow passage 22 spiral pipe 23 combustion gas passage WS dilute solution CS concentrated solution VR refrigerant vapor HF heating fluid

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Kitani 3-8-24-701, Nanko, Nakano, Suminoe-ku, Osaka-shi, Osaka (56) References JP-A-4-347469 (JP, A) 69568 (JP, U) JP-A-3-61263 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F25B 33/00

Claims (3)

(57) [Claims] 1. A front and rear left and right side plate which are substantially vertically upright, top and bottom plates respectively arranged at upper and lower end portions of a side plate so as to constitute a housing in combination with the side plate, and a lower portion. A lower flat side bar integrally fixed to the lower inner wall of the side plate at a predetermined distance from the bottom plate to form an outer header, and a predetermined distance from the top plate to form an upper outer header. An upper flat sidebar integrally secured to an upper inner wall of the side plate; and a width extending vertically, spaced apart from each other inside the housing and penetrating through the lower and upper flat sidebars. Tube plates with narrow internal space and each internal space At the lower and upper ends thereof have openings communicating with the lower and upper outer headers, respectively, and between the lower and upper flat sidebars, the interior of the housing is liquid-tight, and A baffle plate for gas-liquid separation provided above the upper end opening of the internal space, and provided on each outer wall surface of the tube plate located between the lower and upper flat sidebars, the upper and lower portions of the heating fluid Heat transfer fins each having an inflow and an outflow passage, wherein a dilute solution flows into the inner space of the tube plate from the lower outer header, and a heating fluid is supplied to the upper and lower flat side bars. Between the heat transfer fins from above to below along the outer wall surface of each tube plate. The dilute solution flows in while being touched, and is heated by the heat of the heating fluid transmitted through the heat transfer fins and the side wall of the tube plate while the dilute solution rises along each internal space, and gradually becomes refrigerant vapor and The concentrated solution becomes a gas-liquid two-phase, continues to rise, flows out of the upper end opening of the internal space into the upper outer header, and the concentrated solution is separated from the refrigerant vapor by the baffle plate and collected. A regenerator for an absorption refrigerator. 2. The regeneration for an absorption refrigerator according to claim 1, wherein heat transfer fins that contact the inner side surface of the tube plate are also provided in the internal space of each of the plurality of tube plates. vessel. 3. The method according to claim 1, wherein the heating fluid is caused to flow in a countercurrent to the dilute solution.
3. The regenerator for an absorption refrigerator according to any one of 2. and 2.