CN105444467B

CN105444467B - Absorption heat pump

Info

Publication number: CN105444467B
Application number: CN201510590557.XA
Authority: CN
Inventors: 竹村与四郎; 青山淳; 山田宏幸; 入江智芳
Original assignee: Ebara Refrigeration Equipment and Systems Co Ltd
Current assignee: Ebara Refrigeration Equipment and Systems Co Ltd
Priority date: 2014-09-19
Filing date: 2015-09-16
Publication date: 2020-02-14
Anticipated expiration: 2035-09-16
Also published as: JP6429550B2; JP2016061519A; CN105444467A

Abstract

The invention provides an absorption heat pump, which can restrain the heat conduction efficiency to the heated medium from reducing. The absorption heat pump is provided with an absorber (10) which heats a heating medium (W) flowing through a heat transfer pipe (12) by absorption heat generated when an absorption liquid (Sa) absorbs refrigerant vapor (Ve) and evaporates the heating medium (W) in the heat transfer pipe (12), wherein the heat transfer pipe (12) is provided with a preheating pipe (12p) which heats the heating medium liquid (Wq) and an evaporation pipe (12e) which evaporates the heating medium liquid (Wq) heated by the preheating pipe (12 p). The absorber (10) is configured such that one end of each of the evaporation tubes (12e) is connected to an evaporation tube distribution section (14es), the other end is connected to an evaporation tube collection section (14ec), the evaporation tube distribution section (14es) and the evaporation tube collection section (14ec) are each configured by one, and the medium (W) to be heated flowing in each of the plurality of evaporation tubes (12e) does not merge between the evaporation tube distribution section (14es) and the evaporation tube collection section (14 ec).

Description

Absorption heat pump

Technical Field

The present invention relates to an absorption heat pump, and more particularly, to an absorption heat pump that suppresses a decrease in heat transfer efficiency of transferring heat to a medium to be heated.

Background

An absorption heat pump is known in which refrigerant vapor generated in an evaporator is guided to an absorber, and in the absorber, liquid of a medium to be heated is heated by absorption heat generated when an absorption solution absorbs the refrigerant vapor, thereby generating vapor of the medium to be heated. In order to avoid the situation that when the liquid of the heated medium is changed into vapor, the flow of the heated medium becomes unstable due to the obstruction of the increase in volume, the absorber is configured as follows. A plurality of pipes for allowing a medium to be heated to flow therein are horizontally arranged in the absorber. And water cavities are respectively arranged at the two ends of the plurality of pipes. The water chamber is divided into a plurality of chambers by a plurality of partition plates. A plurality of tubes are connected to each water chamber partitioned by the partition plate. In addition, the partition plate should be set to: the water chamber is divided so that the heated medium flowing as a single flow as a whole in each of the tubes and the water chamber becomes a flow from the lower side to the upper side as a whole. In addition, the partition plate is provided with: the total area of the flow passage cross-sectional areas of a set of tubes through which a heating medium led out from a certain water chamber flows is equal to or larger than the total area of the flow passage cross-sectional areas of a set of tubes through which a heating medium introduced into the water chamber flows (see, for example, patent document 1).

Patent document 1: japanese patent laid-open No. 2010-164248 (paragraphs 0034 to 0037, etc.)

The medium to be heated flowing through the pipe is heated by the heat of absorption, and a part of the liquid is evaporated and flows along with the gas. In this case, for example, when the medium to be heated is water, the volume of the evaporated gas is several hundred times as large as the volume of the liquid, and therefore, when the medium to be heated flows out from the lower tube group and flows into the next upper tube group in a certain water chamber, there is a case where a tube into which only the gas flows but not the liquid flows occurs depending on the flow conditions. In the pipe into which only gas flows, the absorption heat cannot be efficiently transferred to the medium to be heated.

Disclosure of Invention

The present invention has been made in view of the above problems, and an object of the present invention is to provide an absorption heat pump having excellent heat transfer efficiency, which can prevent the generation of an evaporation tube in which a vapor of a medium to be heated flows into the evaporation tube without flowing into a liquid of the medium to be heated, and can suppress a decrease in heat transfer efficiency of transferring heat to the medium to be heated.

In order to achieve the above object, an absorption heat pump according to a first aspect of the present invention, as shown in fig. 3, for example, includes an absorber 10 that circulates a liquid Wq of a medium to be heated through a plurality of heat transfer pipes 12, drops an absorption liquid Sa outside the heat transfer pipes 12, heats the medium W to be heated that circulates through the heat transfer pipes 12 by absorption heat generated when the absorption liquid Sa absorbs a vapor Ve of a refrigerant, and evaporates the medium W in the heat transfer pipes 12, and the heat transfer pipes 12 include: a preheating pipe 12p for introducing and heating the liquid Wq of the medium to be heated; and an evaporation tube 12e for introducing and heating the liquid Wq of the medium to be heated, which has been heated by the preheating tube 12p, to evaporate the liquid, and arranging the evaporation tube 12e and the preheating tube 12p so that the absorption liquid Sa falls in the order of the evaporation tube 12e and the preheating tube 12p, wherein the absorber 10 has an outflow passage 84, and the outflow passage 84 is configured to: one end of each of the evaporation tubes 12e is connected to an evaporation tube distribution portion 14es that distributes the medium W to be heated to the plurality of evaporation tubes 12e, the other end of each of the evaporation tubes 12e is connected to an evaporation tube collection portion 14ec that collects the medium W to be heated from the plurality of evaporation tubes 12e, and the medium W to be heated is made to flow out of the absorber 10 from the evaporation tube collection portion 14ec, and the evaporation tube distribution portion 14es and the evaporation tube collection portion 14ec are each configured by one, and are configured such that: the medium W to be heated flowing through the plurality of evaporation tubes 12e does not merge from the evaporation tube distribution portion 14es to the evaporation tube collection portion 14 ec.

With the above configuration, it is possible to prevent the liquid of the medium to be heated flowing into each evaporation tube from evaporating before flowing into each evaporation tube, and it is possible to prevent the evaporation tubes from generating a vapor of the medium to be heated that flows into the evaporation tubes without flowing into the liquid of the medium to be heated, and it is possible to suppress a decrease in heat transfer efficiency of heat transfer to the liquid of the medium to be heated. In addition, since the liquid of the medium to be heated is preheated before being supplied to the evaporation tube, the generation of the steam of the medium to be heated in the evaporation tube can be efficiently performed.

In addition, an absorption heat pump according to a second aspect of the present invention is, for example, as shown with reference to fig. 3, configured such that: the heat received by the preheating tubes 12p from the absorption heat becomes heat that heats the liquid Wq of the medium to be heated flowing into the evaporation tube distribution portion 14es in a range that does not substantially include the steam Wv of the medium to be heated.

With the above configuration, it is possible to prevent, with a higher probability, the evaporation tubes from generating vapor that flows into the medium to be heated without flowing into the liquid of the medium to be heated.

In the absorption heat pump according to the third aspect of the present invention, for example, referring to fig. 3, the total heat transfer area of the plurality of evaporation tubes 12e is 1 time or more and 10 times or less the total heat transfer area of the preheat tube 12 p.

With the above configuration, it is possible to suppress the steam from being mixed into the medium to be heated introduced into the evaporation target liquid distribution portion.

An absorption heat pump according to a fourth aspect of the present invention, as shown in fig. 4, for example, includes: a gas-liquid separator 80 that separates a mixed fluid Wm of liquid and steam of the heated medium flowing out of the outflow flow path 84 into: vapor Wv of the heated medium and liquid Wq of the heated medium; a circulating liquid flow path 82 that guides the liquid Wq of the medium to be heated in the gas-liquid separator 80 to the evaporation tube distribution portion 14 es; and an introduction flow path 85 for introducing the liquid Wq of the heating medium W before heating by the absorption heat to the preheating pipe supply section 14ps for supplying the heating medium W to the preheating pipe 12 p.

With the above configuration, since the liquid of the heated medium from the gas-liquid separator having a high temperature is guided to the evaporation tube distribution portion, the efficiency of the heated medium when absorbing heat can be improved.

In an absorption heat pump according to a fifth aspect of the present invention, for example, as shown in fig. 4, a preheating pipe 12p is formed of a plurality of paths, and the plurality of paths are provided with: a plurality of preheating pipe supply parts 14ps and 14pm for supplying the heating medium W to the preheating pipe 12p, and a plurality of preheating pipe recovery parts 14pm and 14es for recovering the heating medium W heated by the preheating pipe 12 p.

With the above configuration, when the liquid of the medium to be heated having a low temperature is introduced for replenishment, the liquid of the medium to be heated introduced into the liquid distribution portion to be evaporated can be raised to a temperature close to the boiling temperature.

In addition, in an absorption heat pump according to a sixth aspect of the present invention, for example, as shown in fig. 3, the preheating pipe 12p is configured by a single path having: one preheating pipe supply section 14ps that supplies the heating medium W to the preheating pipe 12p, and one preheating pipe recovery section 14es that recovers the heating medium W heated by the preheating pipe 12 p.

With the above configuration, the heated medium introduced into the evaporation target liquid distribution portion can be prevented from being introduced in an evaporated state.

In an absorption heat pump according to a seventh aspect of the present invention, for example, as shown in fig. 5, the evaporation tube distribution unit 14es is configured to: the cross-sectional area of the surface orthogonal to the evaporation tube mounting wall 14Aj between the evaporation tube mounting wall 14Aj to which the plurality of evaporation tubes 12e are mounted and the inner wall 14Ag facing the evaporation tube mounting wall 14Aj is: the position where the medium W to be heated flows into the evaporation tube distribution portion 14es gradually decreases toward the evaporation tube 12e farthest from the preheating tube 12 p.

With the above configuration, variations in the flow rate of the liquid of the medium to be heated flowing into each evaporation tube can be suppressed.

In the absorption heat pump according to the eighth aspect of the present invention, for example, as shown in fig. 3, the absorber 10 has a purge discharge pipe 17, and the purge discharge pipe 17 is provided below the evaporation pipe distribution portion 14es and discharges the heating medium W.

With the above configuration, the evaporation residue generated in the evaporation tube can be appropriately discharged.

According to the present invention, it is possible to prevent the liquid of the medium to be heated flowing into each evaporation tube from evaporating before flowing into each evaporation tube, and thus it is possible to prevent the evaporation tubes from generating a vapor of the medium to be heated which flows into the evaporation tubes without flowing into the liquid of the medium to be heated, and it is possible to suppress a decrease in heat transfer efficiency of heat transfer to the liquid of the medium to be heated. In addition, since the liquid of the medium to be heated is preheated before being supplied to the evaporation tube, the generation of the steam of the medium to be heated in the evaporation tube can be efficiently performed.

Drawings

Fig. 1 is a schematic system diagram of an absorption heat pump according to an embodiment of the present invention.

Fig. 2 is a diagram of a dunline diagram of an absorption heat pump according to an embodiment of the present invention.

Fig. 3 is a sectional view around an absorber of an absorption heat pump according to an embodiment of the present invention.

Fig. 4 is a sectional view showing a first modification of the absorber provided in the absorption heat pump according to the embodiment of the present invention.

Fig. 5 is a sectional view showing a second modification of the absorber provided in the absorption heat pump according to the embodiment of the present invention.

Fig. 6 is a sectional view showing a third modification of the absorber provided in the absorption heat pump according to the embodiment of the present invention.

Fig. 7 is a sectional view showing a fourth modification of the absorber provided in the absorption heat pump according to the embodiment of the present invention.

Fig. 8 is a schematic system diagram of a two-stage heating absorption heat pump according to a modification of the embodiment of the present invention.

Description of reference numerals: 1 … absorption heat pump; 10 … absorber; 12 … heat conduction pipe; 12e … evaporator tube; 12p … preheat tube; 14ec … mixed fluid chamber; 14es … high temperature liquid storage chamber; 14pm … relay liquid chamber; 14ps … low temperature liquid storage chamber; 14Aj … tubesheet; 14Ag … inner wall; 17 … purge drain; 80 … gas-liquid separator; 82 … heated medium liquid pipe; 84 … outflow tube; 85 … make up water pipe; concentrated solution Sa …; ve … evaporator refrigerant vapor; w … heated medium; wm … mixing the heated media; wq … is heated with the medium liquid; wv … is heated by the medium steam.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or similar reference numerals are assigned to the same or corresponding members, and redundant description thereof is omitted.

First, an absorption heat pump 1 according to an embodiment of the present invention will be described with reference to fig. 1. Fig. 1 is a schematic system diagram of an absorption heat pump 1. First, the overall structure and operation of the absorption heat pump 1 will be described, and then the absorber 10, which is one of the components of the absorption heat pump 1, will be described in detail. The absorption heat pump 1 includes an absorber 10, an evaporator 20, a regenerator 30, and a condenser 40, which constitute main devices of an absorption heat pump cycle that performs absorption liquid S (Sa, Sw) and refrigerant V (Ve, Vg, Vf), and further includes a gas-liquid separator 80.

In the present specification, the absorbing liquid is generally referred to as "absorbing liquid S" or "solution S" in consideration of properties and the position on the heat pump cycle, although the absorbing liquid is referred to as "dilute solution Sw" or "concentrated solution Sa" in consideration of properties and the like so as to easily distinguish the absorbing liquid from the heat pump cycle. Also, regarding the refrigerant, in order to facilitate the distinction in the heat pump cycleThe terms "evaporator refrigerant vapor Ve", "regenerator refrigerant vapor Vg", "refrigerant liquid Vf" and the like are used depending on the properties and the position on the heat pump cycle, but are generically referred to as "refrigerant V" regardless of the properties and the like. In the present embodiment, an aqueous LiBr solution is used as the absorbent S (mixture of the absorbent and the refrigerant V), and water (H) is used₂O) as refrigerant V. The medium W is a generic name of a liquid Wq of the medium W to be heated as a liquid to be supplied to the absorber 10, a vapor Wv of the medium to be heated as a gas, a mixed medium Wm of the medium to be heated in a state where the liquid and the gas are mixed, and a makeup water Ws of a makeup liquid as a makeup liquid of the medium to be heated to be replenished from outside the absorption heat pump 1. In the present embodiment, water (H) is used₂O) as the heating medium W.

The absorber 10 has therein: a heat transfer pipe 12 that constitutes a flow path for the medium W to be heated; and a concentrated solution scattering nozzle 13 as an absorption liquid scattering device for scattering the concentrated solution Sa. The absorber 10 spreads the rich solution Sa from the rich solution spreading nozzle 13 and generates absorption heat when the rich solution Sa absorbs the evaporator refrigerant vapor Ve. The absorber 10 is configured to receive the absorption heat from the heating target medium W flowing through the heat transfer pipe 12 and heat the heating target medium W. The evaporator 20 has therein: a heat source pipe 21 that constitutes a flow path of heat source hot water h as a heat source fluid; and a refrigerant liquid distributing nozzle 22 that distributes the refrigerant liquid Vf to the heat source pipe 21. The evaporator 20 is configured to generate evaporator refrigerant vapor Ve by spreading refrigerant liquid Vf from the refrigerant liquid spreading nozzle 22 and evaporating the spread refrigerant liquid Vf using heat of the heat source hot water h flowing through the heat source tube 21. The absorber 10 and the evaporator 20 are formed in one tank body in such a manner as to communicate with each other. The absorber 10 and the evaporator 20 are configured to communicate with each other so that the evaporator refrigerant vapor Ve generated in the evaporator 20 can be supplied to the absorber 10.

The regenerator 30 has: a heat source pipe 31 through which a heat source hot water h serving as a heat source fluid for heating the dilute solution Sw flows; and a dilute solution dispersing nozzle 32 which disperses the dilute solution Sw. The heat source hot water h flowing through the heat source pipe 31 may be the same fluid as the heat source hot water h flowing through the heat source pipe 21 or may be a different fluid. The regenerator 30 is configured to be heated by the heat source hot water h by the dilute solution Sw sprayed from the dilute solution spraying nozzle 32, and to generate the concentrated solution Sa having an increased concentration by evaporating the refrigerant V from the dilute solution Sw. The refrigerant V evaporated from the dilute solution Sw is configured to move to the condenser 40 as the regenerator refrigerant vapor Vg. The condenser 40 has a cooling water pipe 41 through which cooling water c as a cooling medium flows. The condenser 40 is configured to introduce the regenerator refrigerant vapor Vg generated by the regenerator 30, and to cool and condense it with the cooling water c. The regenerator 30 and the condenser 40 are formed in one tank body in such a manner as to communicate with each other. The regenerator 30 and the condenser 40 are configured to communicate with each other, and thereby the regenerator refrigerant vapor Vg generated in the regenerator 30 can be supplied to the condenser 40. The absorber 10 and the evaporator 20 are disposed at a higher position than the regenerator 30 and the condenser 40, and are configured to be able to convey the absorption liquid S in the absorber 10 to the regenerator 30 and the refrigerant liquid Vf in the evaporator 20 to the condenser 40, respectively, by using a position head.

The portion of the regenerator 30 where the rich solution Sa is stored is connected to the rich solution distribution nozzle 13 of the absorber 10 with a rich solution pipe 35 through which the rich solution Sa flows. A solution pump 35p for pressure-feeding the concentrated solution Sa is provided in the concentrated solution pipe 35. The portion of the absorber 10 where the dilute solution Sw is stored is connected to the dilute solution distribution nozzle 32 with a dilute solution pipe 36 through which the dilute solution Sw flows. A solution heat exchanger 38 that exchanges heat between the rich solution Sa and the lean solution Sw is disposed in the rich solution pipe 35 and the lean solution pipe 36. The portion of the condenser 40 storing the refrigerant liquid Vf is connected to the refrigerant liquid distribution nozzle 22 of the evaporator 20 by a refrigerant liquid pipe 45 through which the refrigerant liquid Vf flows. A refrigerant pump 46 that pressurizes and conveys the refrigerant liquid Vf is disposed in the refrigerant liquid pipe 45. The portion of the evaporator 20 in which the unevaporated refrigerant liquid Vf is stored is connected to the condenser 40 by a refrigerant liquid pipe 25 that returns the unevaporated refrigerant liquid Vf distributed from the refrigerant liquid distribution nozzle 22 to the condenser 40. A refrigerant heat exchanger 48 is disposed in the refrigerant liquid pipe 25 and the refrigerant liquid pipe 45, and performs heat exchange between the refrigerant liquids Vf flowing through the respective pipes 25 and 45.

The gas-liquid separator 80 is a device that introduces the heating medium W heated by flowing through the heat transfer pipe 12 of the absorber 10 and separates the heating medium vapor Wv from the heating medium liquid Wq. The gas-liquid separator 80 and the absorber 10 are connected by a heating medium liquid pipe 82 that guides the heating medium liquid Wq in the gas-liquid separator 80 to the heat transfer pipe 12 and an outflow pipe 84 that is an outflow passage that guides the heated heating medium W to the gas-liquid separator 80. Further, a heating medium steam pipe 89 is connected to the gas-liquid separator 80, and the separated heating medium steam Wv is guided to the outside of the absorption heat pump 1. Further, a makeup water pipe 85 is provided to introduce makeup water Ws for replenishing the medium W to be heated, which is supplied mainly as steam to the outside of the absorption heat pump 1, from the outside of the absorption heat pump 1. The makeup water pipe 85 is connected to the heating medium liquid pipe 82, and is configured to join the makeup water Ws and the heating medium liquid Wq flowing through the heating medium liquid pipe 82. A makeup water pump 86 is disposed in the makeup water pipe 85 to pressurize and feed the makeup water Ws to the absorber 10.

The heat pump cycle of the absorption heat pump 1 will be described with reference to fig. 1 and the durin diagram of fig. 2. The durin diagram of fig. 2 is a diagram in which the vertical axis represents the dew point temperature of the refrigerant V (water in the present embodiment) and the horizontal axis represents the temperature of the solution S (aqueous solution of LiBr in the present embodiment). The upper right line represents the isoconcentration line of the solution S, with higher concentrations to the right and lower concentrations to the left. The line going to the upper right through the dew point temperature 0 deg.c in the figure is the line for solution concentration 0% (i.e. refrigerant only). Since the dew point temperature and the saturation pressure shown on the ordinate have a corresponding relationship, the internal pressure of the

main components

10, 20, 30, and 40 can be regarded as being shown on the ordinate in the heat pump cycle of the present embodiment in which the refrigerant vapors Ve and Vg are saturated vapors.

First, the refrigerant-side cycle is explained. In the condenser 40, the regenerator refrigerant vapor Vg evaporated by the regenerator 30 is received and cooled and condensed into the refrigerant liquid Vf by the cooling water c flowing through the cooling water pipe 41 (v 1). The condensed refrigerant liquid Vf is sent to the refrigerant liquid distribution nozzle 22 of the evaporator 20 by the refrigerant pump 46. The refrigerant liquid Vf sent to the refrigerant liquid distribution nozzle 22 is distributed to the heat source pipe 21, heated by the heat source hot water h flowing through the heat source pipe 21, and evaporated to become the evaporator refrigerant vapor Ve (v 2). The evaporator refrigerant vapor Ve generated by the evaporator 20 moves toward the absorber 10 communicating with the evaporator 20.

Next, circulation on the solution side will be described. In the absorber 10, the concentrated solution Sa is dispersed from the concentrated solution dispersing nozzle 13, and the dispersed concentrated solution Sa absorbs the evaporator refrigerant vapor Ve moving from the evaporator 20. The concentrated solution Sa having absorbed the evaporator refrigerant vapor Ve becomes a dilute solution Sw (j to k) with a decreased concentration. In the absorber 10, absorption heat is generated when the rich solution Sa absorbs the evaporator refrigerant vapor Ve. The medium W to be heated flowing through the heat transfer pipe 12 is heated by the absorption heat. The concentrated solution Sa having absorbed the evaporator refrigerant vapor Ve by the absorber 10 is reduced in concentration to become a dilute solution Sw and is accumulated in the lower portion of the absorber 10. The stored lean solution Sw flows toward the regenerator 30 in the lean solution pipe 36 due to gravity and a difference between the internal pressures of the absorber 10 and the regenerator 30, exchanges heat with the rich solution Sa in the solution heat exchanger 38, decreases in temperature (k to m), and reaches the regenerator 30. When the dilute solution Sw flows out of the solution heat exchanger 38 and enters the regenerator 30, the pressure (dew point temperature) decreases, and the temperature decreases (m to n) as a part of the refrigerant V in the dilute solution Sw evaporates.

The dilute solution Sw sent to the regenerator 30 is sprayed from the dilute solution spraying nozzle 32, and is heated by the heat source hot water h (about 80 ℃ in the present embodiment) flowing through the heat source pipe 31, so that the refrigerant in the sprayed dilute solution Sw evaporates to become the concentrated solution Sa (n to p), and is accumulated in the lower portion of the regenerator 30. On the other hand, the refrigerant V evaporated from the dilute solution Sw moves to the condenser 40 as the regenerator refrigerant vapor Vg. The rich solution Sa stored in the lower portion of the regenerator 30 is sent under pressure to the rich solution distribution nozzle 13 of the absorber 10 via the rich solution pipe 35 by the solution pump 35 p. The rich solution Sa flowing in the rich solution pipe 35 exchanges heat with the lean solution Sw in the solution heat exchanger 38, flows into the absorber 10(p to q) after the temperature rises, and is dispersed from the rich solution dispersion nozzle 13. The rich solution Sa is pressurized by the solution pump 35p and enters the absorber 10, and the temperature thereof rises (q to j) as the evaporator refrigerant vapor Ve is absorbed in the absorber 10. The rich solution Sa returned to the absorber 10 absorbs the evaporator refrigerant vapor Ve, after which the same cycle is repeated.

In the course of the absorption heat pump cycle in which the absorption liquid S and the refrigerant V are subjected to the above-described absorption heat pump cycle, the absorber 10 heats the heating medium liquid Wq to wet steam (mixed heating medium Wm) by absorption heat generated when the evaporator refrigerant steam Ve is absorbed by the rich solution Sa, and the heating medium steam Wv separated by being guided to the gas-liquid separator 80 is supplied to the outside steam utilization location of the absorption heat pump 1. That is, the heating medium steam Wv is taken out from the absorption heat pump. The medium W to be heated supplied to the outside is supplied from the outside of the absorption heat pump 1 as the makeup water Ws. The respective devices constituting the absorption heat pump 1 are controlled by a control device (not shown).

Next, the absorber 10 constituting the absorption heat pump 1 (see fig. 1) will be described in detail with reference to fig. 3. Fig. 3 is a sectional view around the absorber 10 of the absorption heat pump 1 shown in fig. 1. The absorber 10 is configured such that a heat transfer pipe 12 and a concentrated solution distribution nozzle 13 are housed in a tank 11, and a water chamber forming member 14 as a heated medium chamber forming member is provided outside the tank 11. The water chamber forming member 14 is a member that supplies the heating target medium W to the heat transfer pipes 12 or forms a water chamber as a heating target medium chamber in which the heating target medium W is collected from the heat transfer pipes 12. The can body 11 is typically formed in a horizontally long shape when installed.

In the present embodiment, the heat transfer pipe 12 is provided with a plurality of linearly formed members in the tank 11. The heat transfer pipe 12 is joined to one end of the rectangular can 11 and the other end on the opposite side. The surface of the can 11 to which the heat transfer tubes 12 are joined is formed as a tube plate (heat transfer tube plate) formed with a hole through which the heat transfer tubes 12 can be inserted. The interiors of the heat transfer pipes 12 joined to the tube plates at both ends of the tank 11 do not communicate with the interior of the tank 11. In other words, the medium W to be heated flowing through the heat transfer tubes 12 is not mixed with the absorbent S and the refrigerant V flowing out of and into the tank 11. In the specific example shown, the heat transfer tubes 12 are fixed by expansion to holes formed in the tube sheet of the tank 11.

The heat transfer pipe 12 is distinguished by its function as a preheating pipe 12p and an evaporation pipe 12 e. The preheating pipe 12p is a pipe for introducing the heating medium liquid Wq, and heating and raising the temperature of the introduced heating medium liquid Wq by the absorption heat. The evaporation tube 12e is a tube into which the heating medium liquid Wq heated in the preheating tube 12p is introduced and which evaporates the introduced heating medium liquid Wq by the heat of absorption. At least a part of the heating medium liquid Wq flowing in from one end of the evaporation tube 12e evaporates to flow out from the other end, and becomes the heating medium vapor Wv. The evaporation tube 12e is disposed above the preheating tube 12 p. In the present embodiment, each heat transfer pipe 12 is disposed so that the axes of the preheating pipe 12p and the evaporation pipe 12e are both horizontal. In consideration of heating and boiling the heating medium liquid Wq in the evaporation tube 12e, it is also conceivable to arrange the evaporation tube 12e such that the axis thereof is vertical. However, in the present embodiment, the evaporation tube 12e is disposed so that the axis thereof is horizontal, from the viewpoint of allowing the scattered absorption liquid S to contact as much as possible of the outer surface of the evaporation tube 12e as a thin liquid film. From the viewpoint of facilitating the production, the preheating pipe 12p is also arranged so that the axis thereof is horizontal, as in the evaporation pipe 12 e.

The preheating pipe 12p disposed at the lowermost portion in the vertical direction among the heat transfer pipes 12 provided in the tank 11 is disposed at a position where a portion (space) in which the dilute solution Sw is stored is secured. With such a configuration, during steady operation, the heat transfer pipe 12 does not enter the absorbent S, and the evaporator refrigerant vapor Ve is absorbed by the concentrated solution Sa spreading on the surface of the heat transfer pipe 12, so that the contact area between the concentrated solution Sa and the evaporator refrigerant vapor Ve can be increased, and the generated absorption heat can be rapidly transferred to the heating target medium W flowing through the heat transfer pipe 12, thereby accelerating recovery of the absorption capacity. On the other hand, the evaporation pipe 12e disposed at the uppermost portion of the tank 11 is disposed at a position where a space in which the concentrated solution scattering nozzle 13 can be disposed is secured.

The water chamber forming member 14 is attached to both surfaces (tube sheets) of the can body 11 to which the end portions of the respective heat transfer tubes 12 are joined. The water chamber forming member 14 is a rectangular parallelepiped member having an opening on one surface, and is attached to the tube plate of the tank 11 so that the opening surface covers one end of the plurality of heat transfer tubes 12 attached to the tube plate of the tank 11. Since the water chamber forming member 14 is attached to the tube plate of the tank 11, a space surrounded by the water chamber forming member 14 and the tube plate of the tank 11 becomes a water chamber. The water chamber communicates with the inside of each heat transfer pipe 12. That is, the medium W flows into and out of the water chamber. When a plurality of water chambers are formed by dividing the inside of the water chamber forming member 14, a partition plate 15 is provided inside the water chamber forming member 14. One end of heat transfer pipe 12 through which heating medium W flows into the water chamber and/or one end of heat transfer pipe 12 through which heating medium W flows out of the water chamber communicate with each water chamber partitioned by partition plate 15.

Partition plate 15 is provided with one or more heat transfer pipes 12 that allow heating medium W to flow into and out of one of the water chambers, and the water chambers on the opposite side communicate with different water chambers. Thus, the heating medium W flowing through the heat transfer pipes 12 and the water chamber is configured to: the absorber 10 is formed as a whole in a serpentine flow so that the flow from the most upstream water chamber flows in one direction through the heat transfer pipe 12 communicating with the water chamber, and the flow changes in the opposite direction and flows in the opposite direction through the other heat transfer pipe 12 communicating with the water chamber. The partition plate 15 is provided to partition the water chamber so that the medium W to be heated, which flows as a single liquid flow with the heat transfer pipes 12 and the water chamber as a whole, flows upward from below in the absorber 10 as a whole.

The water chamber in one of the two water chamber forming members 14 respectively installed on both sides of the tank 11, the water chamber in one water chamber forming member 14, is partitioned by a partition plate 15, and is thus partitioned into a low-temperature liquid storage chamber 14ps and a mixed fluid chamber 14 ec. In addition, the other water chamber forming member 14 is provided with no partition plate 15, and is formed as a high-temperature liquid storage chamber 14es as a whole.

One end of one or more preheating pipes 12p is connected to the low-temperature liquid storage chamber 14ps in the side sectional view shown in fig. 3. One end of the preheating pipes 12p is connected to the low-temperature liquid reservoir 14ps, and the other end thereof is connected to the high-temperature liquid reservoir 14 es. In this way, in the present embodiment, one kind of the preheating pipe 12p connecting the low-temperature liquid storage chamber 14ps and the high-temperature liquid storage chamber 14es is provided. Here, the low-temperature reservoir 14ps is a water chamber for supplying the heating medium liquid Wq to one type of the preheating pipe 12p, and corresponds to a preheating pipe supply portion. The high-temperature liquid reservoir 14es is a water chamber for recovering the heated medium liquid Wq heated by a kind of the preheating pipe 12p, and corresponds to a preheating pipe recovery section. In the present embodiment, one preheating pipe supply unit (low-temperature liquid storage chamber 14ps) and one preheating pipe recovery unit (high-temperature liquid storage chamber 14es) are provided, and the preheating pipe 12p is constituted by a single path. Here, the "route" means: the fluid flowing through one heat transfer pipe 12 does not join the fluid flowing through the other heat transfer pipe 12, and flows in the unit of the flow path flowing without changing 180 degrees. The number of the paths is not limited as long as the flow direction of the fluid flowing through the heat transfer tubes 12 is not changed by 180 degrees and the fluid does not join in the middle.

In addition to the above-described preheating pipe 12p, one end of a plurality of evaporation pipes 12e is connected to the high-temperature liquid storage chamber 14 es. One end of the evaporation tube 12e is connected to the high-temperature liquid storage chamber 14es, and the other end thereof is connected to the mixed fluid chamber 14 ec. In the present embodiment, one end of all the evaporation tubes 12e disposed in the tank 11 is connected to the high-temperature liquid storage chamber 14es, and the other end is connected to the mixed fluid chamber 14 ec. Here, the high-temperature liquid storage chamber 14es is a water chamber for distributing the heating medium liquid Wq to the plurality of evaporation tubes 12e, and corresponds to an evaporation tube distribution portion. That is, the high-temperature liquid storage chamber 14es serves as both the preheating pipe recovery section and the evaporation pipe distribution section. The mixed fluid chamber 14ec is a water chamber for collecting the heating medium W from the plurality of evaporation tubes 12e, and corresponds to an evaporation tube collection unit. A purge discharge pipe 17 capable of discharging the heated medium liquid Wq is provided at a lower portion (typically, a bottom portion) of the high-temperature liquid storage chamber 14 es. A purge discharge valve 17v is disposed in the purge discharge pipe 17. An outflow pipe 84 is connected to an upper portion of the mixed fluid chamber 14 ec. The preheating pipe 12p and the evaporation pipe 12e arranged as described above are designed in the following manner.

First, the temperature of the medium W to be heated introduced into the low-temperature liquid storage chamber 14ps and the temperature of the medium W to be heated in the mixed fluid chamber 14ec are set (a medium-to-be-heated temperature setting step). The temperature of the medium W to be heated in the mixed fluid chamber 14ec is the saturation temperature of the mixed medium Wm. Next, the heat transfer area of the preheating pipe 12p (the outer surface area of the preheating pipe 12p) is set so that the heat received by the preheating pipe 12p from the absorption heat becomes heat heated within a predetermined range (preheating pipe heat transfer area setting step). The predetermined range is a range in which the heating medium liquid Wq flowing into the high-temperature liquid storage chamber 14es does not substantially include the heating medium vapor Wv. The fact that the heated medium vapor Wv is not included means: when the heated medium W flows into each evaporation tube 12e from the high-temperature liquid storage chamber 14es, it is allowed to include the heated medium vapor Wv to such an extent that the evaporation tube 12e into which only the heated medium vapor Wv enters is not generated. The preheating pipe 12p is preferably formed to have a flow path cross-sectional area such that the flow velocity of the heating medium liquid Wq flowing inside is 0.5 to 2 m/s. The amount of heat supplied to the preheating pipe 12p varies depending on the heat transfer area of the preheating pipe 12p, the heat transfer method in the preheating pipe 12p, the flow rate of the heating medium liquid Wq flowing in the preheating pipe 12p, and the like. Next, the heat transfer area of the evaporation tube 12e (the outer surface area of the evaporation tube 12e) is set so that the evaporation tube 12e can obtain the medium-to-be-heated vapor Wv at a desired flow rate by absorbing the heat received by the heat (evaporation tube heat transfer area setting step). Further, the equivalent heat transfer area of the preheating pipe 12p is changed in accordance with the pressure of the medium-to-be-heated vapor Wv generated by the evaporation pipe 12e and the temperature of the medium-to-be-heated liquid Wq supplied to the low-temperature reservoir 14 ps. The ratio of the total heat transfer area of the evaporation tube 12e to the total heat transfer area of the preheating tube 12p may be set as follows when the pressure of the medium to be heated W is 0.1 to 0.8MPa (gauge pressure) and the temperature of the medium to be heated Wq supplied to the low-temperature liquid reservoir 14ps is 20 to 80 ℃. That is, from the viewpoint of suppressing the heating medium liquid Wq from evaporating inside the preheating tube 12p as the heat transfer area of the preheating tube 12p becomes excessively large, the total heat transfer area of the evaporation tube 12e may be 1 time or more, and more preferably 2 times or more, the total heat transfer area of the preheating tube 12 p. In addition, from the viewpoint of suppressing a decrease in the heat transfer area of the evaporation tube 12e for evaporation and deterioration in thermal efficiency due to a partial use of the heat transfer area of the evaporation tube 12e for preheating caused by a shortage of the heat transfer area of the preheating tube 12p, the total heat transfer area of the evaporation tube 12e may be 10 times or less, and more preferably 8 times or less, of the total heat transfer area of the preheating tube 12 p. It is to be noted that, when the turbulence promoter, the fin, the groove, or the like (hereinafter referred to as "turbulence promoter or the like") is provided on the inner and outer surfaces of the heat transfer pipe 12 to promote the heat transfer, a new equivalent heat transfer area obtained by multiplying a heat transfer area in the case where the turbulence promoter or the like is not provided by a ratio at which the heat transfer amount increases as compared with the case where the turbulence promoter or the like is not provided is evaluated as the heat transfer area defined herein.

The concentrated solution distribution nozzle 13 housed in the tank 11 is widely disposed over a wide range covering the heat transfer pipe 12 when viewed vertically upward so as to be able to distribute the concentrated solution Sa without spreading over the heat transfer pipe 12. The concentrated solution pipe 35 connected to the concentrated solution distribution nozzle 13 penetrates one surface of the tank 11. Further, as described above, the plurality of heat transfer tubes 12 are arranged horizontally in the tank 11, but the horizontal arrangement is not strictly required to be horizontal, and may be such a level that even if the medium W to be heated, which flows in a meandering manner in the absorber 10 as one liquid flow, changes from a liquid to a vapor in the evaporation tube 12e, the flow of the medium W to be heated is not hindered. However, from the viewpoint of increasing the amount of the concentrated solution Sa sprayed from the concentrated solution spraying nozzle 13 in contact with the outer surface of the heat conductive pipe 12, the closer to the level, the more preferable. The dilute solution pipe 36 for guiding the dilute solution Sw stored at the bottom of the tank 11 to the regenerator 30 (see fig. 1) is connected to the bottom of the tank 11.

The heating medium liquid Wq in the gas-liquid separator 80 is guided to the heating medium liquid pipe 82 of the absorber 10, and is connected to the low-temperature liquid reservoir 14ps which is the liquid reservoir at the most upstream side of the liquid flow of the heating medium W. The supplementary water pipe 85 is connected to the heated medium liquid pipe 82. According to this configuration, the connection portion of the pipe through which the medium W to be heated flows into the absorber 10 may be set to one position, and the configuration can be simplified, and the maintenance and inspection work when the water chamber is opened can be facilitated. The wet steam (mixed heating medium Wm) generated in the absorber 10 is guided to the outflow pipe 84 of the gas-liquid separator 80 and connected to the mixed fluid chamber 14 ec.

Next, the action around the absorber 10 will be described mainly with reference to fig. 3 and appropriately with reference to fig. 1. The concentrated solution Sa sprayed from the concentrated solution spraying nozzle 13 is pressure-fed from the regenerator 30 by the solution pump 35 p. When the concentrated solution Sa is sprayed from the concentrated solution spraying nozzle 13, it falls by gravity, first falls on the evaporation tube 12e, and the concentrated solution Sa that is not in contact with the evaporation tube 12e and that drops along the surface of the evaporation tube 12e falls on the preheating tube 12p, thereby wetting and spreading on the surface of each evaporation tube 12e and each preheating tube 12 p. The concentrated solution Sa, which has infiltrated and spread over the surfaces of the evaporation tubes 12e and the preheating tubes 12p, absorbs the evaporator refrigerant vapor Ve supplied from the evaporator 20, and heats the medium W to be heated, which flows inside, by the heat of absorption generated at this time. The rich solution Sa having absorbed the evaporator refrigerant vapor Ve becomes a lean solution Sw, and is temporarily stored in the lower portion of the tank 11 and then guided to the regenerator 30 through the lean solution pipe 36.

On the other hand, the heating medium liquid Wq from the gas-liquid separator 80 flows into the low-temperature liquid reservoir 14ps in the absorber 10 through the heating medium liquid pipe 82. The heating medium liquid Wq flowing into the low-temperature liquid storage chamber 14ps is mixed with the makeup water Ws by the makeup water pump 86 before flowing into the low-temperature liquid storage chamber 14 ps. The total flow rate of the heating medium liquid Wq flowing from the makeup water pipe 85 and the gas-liquid separator 80 into the high-temperature liquid reservoir 14es is typically about 2 to 10 times the flow rate of the heating medium vapor Wv generated by the absorber 10. The heated medium liquid Wq flowing into the low-temperature liquid reserving chamber 14ps flows through the preheating pipe 12p and flows into the high-temperature liquid reserving chamber 14 es. When the heating medium liquid Wq flows through the inside of the preheating pipe 12p, the heating medium liquid is heated by absorption heat generated when the evaporator refrigerant vapor Ve is absorbed by the concentrated solution Sa wetting and spreading on the outer surface of the preheating pipe 12 p. At this time, the temperature of the heating medium liquid Wq flowing through the preheating pipe 12p rises, but does not evaporate.

The heated medium liquid Wq in the high-temperature liquid storage chamber 14es flows into the evaporation tubes 12 e. At this time, since the medium-to-be-heated vapor Wv does not substantially exist in the high-temperature liquid reservoir 14es, the medium-to-be-heated liquid Wq flows into all the evaporation tubes 12 e. The heating medium liquid Wq flowing through each evaporation tube 12e is heated by absorption heat generated when the evaporator refrigerant vapor Ve is absorbed by the concentrated solution Sa wetting and spreading on the outer surface of the evaporation tube 12e until it reaches the mixed fluid chamber 14ec, and a part or all of the liquid is evaporated. Here, when the heating medium liquid Wq is water, if the water evaporates to become water vapor, the volume of the water vapor increases several hundred times as much as the water. For example, even if only 1% of the mass of water is evaporated, the volume of water vapor in the entire heating medium W increases by several times as large as that of water. Therefore, even when water having evaporated 1% of its mass flows from the preheating pipe 12p into the high-temperature liquid storage chamber 14es, the volume occupied by the water vapor as the gas exceeds that of the water as the liquid, and depending on the flow state of the heating target medium W, the evaporation pipe 12e through which only the water vapor flows from the high-temperature liquid storage chamber 14es may occur. If there is an evaporation tube 12e into which only gas flows without flowing the liquid of the heating target medium W, the efficiency of heat absorption and conduction to the heating target medium W in the evaporation tube 12e is deteriorated. In the absorption heat pump 1 of the present embodiment, the heating medium vapor Wv can be efficiently generated by flowing the heating medium liquid Wq into all the evaporation tubes 12e and efficiently transferring the absorption heat to the heating medium liquid Wq. The heated medium W flows through the evaporation tube 12e, becomes a mixed heated medium Wm, and reaches the mixed fluid chamber 14 ec. The mixed heated medium Wm in the mixed fluid chamber 14ec flows in the outflow pipe 84 and flows out from the absorber 10. The mixed heating medium Wm generated by the evaporation tubes 12e formed by one path in this way flows out of the absorber 10 without passing through the evaporation tubes.

The mixed heating medium Wm flowing out of the absorber 10 flows into the gas-liquid separator 80 through the outflow pipe 84. The mixed heating medium Wm that has flowed into the gas-liquid separator 80 collides against the baffle plate 80a to be separated into gas and liquid, and is separated into the heating medium liquid Wq and the heating medium vapor Wv. The separated heating medium steam Wv flows through the heating medium steam pipe 89 toward the steam utilization position outside the absorption heat pump 1. On the other hand, the heating medium liquid Wq separated by the gas-liquid separator 80 is stored in the storage portion 81 at the lower portion of the gas-liquid separator 80. The heating medium liquid Wq stored in the separation liquid storage unit 81 flows through the heating medium liquid pipe 82. The heating medium liquid Wq flowing through the heating medium liquid pipe 82 merges with the makeup water Ws from the makeup water pipe 85, flows into the low-temperature liquid reservoir 14ps, and thereafter repeats the above-described operation.

As described above, according to the absorption heat pump 1 of the present embodiment, since the medium W to be heated flowing from the preheating pipe 12p into the high-temperature liquid storage chamber 14es flows in as a liquid (the medium liquid Wq to be heated), evaporation can be avoided before the medium W to be heated flowing into each evaporation pipe 12e flows into each evaporation pipe 12 e. Therefore, the evaporation tubes 12e into which the heating medium vapor Wv flows without flowing into the heating medium liquid Wq can be prevented from being generated in the plurality of evaporation tubes 12e, and a decrease in heat transfer efficiency to the heating medium W flowing through the evaporation tubes 12e can be suppressed. Further, since the preheating pipe 12p is used to preheat the heating medium liquid Wq before it is introduced into the evaporation pipe 12e, the heating medium vapor Wv can be efficiently generated in the evaporation pipe 12 e. Further, since the preheating pipe 12p is constituted by a single path, overheating can be suppressed, and the risk of evaporation of the heating medium liquid Wq flowing into the high-temperature liquid storage chamber 14es can be reduced. Further, the flow path resistance of the preheating pipe 12p can be easily reduced, and the circulation of the heating medium W in the absorber 10A and the gas-liquid separator 80 can be enhanced. In addition, the height of the can body 11 is easily suppressed. Further, since the purge discharge pipe 17 is provided, the purge discharge valve 17v can be opened to appropriately discharge the evaporation residue generated along with the evaporation of the heating medium liquid Wq, and the heating medium liquid Wq in the tank body 11 can be substantially discharged, so that the possibility of the evaporation residue remaining can be minimized. Further, since there is one high-temperature liquid reservoir 14es (evaporation tube distribution portion) for distributing the heating medium liquid Wq to the evaporation tube 12e, there is only one purge valve 17v, and the purge operation can be performed by only operating one purge valve 17v, and the absorber can be operated easily.

Next, an absorber 10A of a modification will be described with reference to fig. 4. The absorber 10A is different from the absorber 10 (see fig. 3) in the following points. Inside the two water chamber forming members 14 attached to the two surfaces of the tank 11, there are provided one partition plate 15, respectively. The water chamber in one 14 of the two water chamber forming members 14 is partitioned by a partition plate 15 so as to be divided into a low-temperature reservoir 14ps and a high-temperature reservoir 14 es. In addition, the water chamber in the other water chamber forming member 14 is partitioned by a partition plate 15 to be divided into a relay liquid chamber 14pm and a mixed fluid chamber 14 ec. One end of one or more preheating pipes 12p is connected to the low-temperature liquid storage chamber 14ps in the side sectional view shown in fig. 4. The other ends of all the preheating pipes 12p connected at one end to the low-temperature liquid storage chamber 14ps are connected to the relay liquid storage chamber 14 pm. The relay liquid storage chamber 14pm is connected to one end of one or more than two preheating pipes 12p in addition to the preheating pipe 12p communicating with the low-temperature liquid storage chamber 14 ps. The other end of the preheating pipe 12p is connected to the high-temperature liquid storage chamber 14 es. In this way, in the present modification, two types of preheating pipes 12p are provided, a preheating pipe 12p connecting the low-temperature reservoir 14ps and the relay reservoir 14pm, and a preheating pipe 12p connecting the relay reservoir 14pm and the high-temperature reservoir 14 es. In the same manner as in the present modification, the low-temperature reservoir 14ps corresponds to a preheating pipe supply unit, and the high-temperature reservoir 14es corresponds to a preheating pipe recovery unit. In the present modification, the intermediate reservoir chamber 14pm is a water chamber for collecting the heating medium liquid Wq heated by one kind of the preheating pipe 12p and supplying the heating medium liquid Wq to the other kind of the preheating pipe 12p, and serves as both a preheating pipe supply unit and a preheating pipe collection unit. That is, in the present modification, two preheating pipe supply portions (the low-temperature reservoir 14ps and the relay reservoir 14pm) and two preheating pipe recovery portions (the relay reservoir 14pm and the high-temperature reservoir 14es) are provided, and the preheating pipe 12p is constituted by two paths.

In the present modification, the heating medium liquid Wq flowing through the heating medium liquid pipe 82 and the makeup water Ws flowing through the makeup water pipe 85 are configured not to merge before flowing into the low-temperature liquid storage chamber 14 ps. The heating medium liquid Wq in the gas-liquid separator 80 is guided to the heating medium liquid pipe 82 of the absorber 10A and connected to the high-temperature liquid storage chamber 14 es. With this configuration, the heating medium liquid Wq from the gas-liquid separator 80 having a high temperature is introduced into the high-temperature liquid chamber 14es, and the heating medium W in the evaporation tube 12e can be efficiently heated. In addition, since the heating medium liquid Wq in the gas-liquid separator 80 is a liquid from which the saturated temperature state of the heating medium vapor Wv is separated, there is no fear that the heating medium vapor Wv exists when being guided to the high-temperature liquid storage chamber 14 es. The supplementary water pipe 85 is connected to the low-temperature liquid storage chamber 14 ps. Therefore, the temperature of the makeup water Ws is the temperature of the medium W to be heated introduced into the low-temperature reservoir 14 ps. With this configuration, the low-temperature makeup water Ws flows into the preheating pipe 12p, and the steam can be prevented from being mixed into the heating medium liquid Wq flowing into the high-temperature liquid reservoir 14 es. In this modification, the heating medium liquid pipe 82 corresponds to a circulation liquid flow path, and the supplementary water pipe 85 corresponds to an introduction flow path. In the absorber 10A shown in fig. 4, the purge discharge pipe 17 (see fig. 3) is not provided, and the purge discharge valve 17v provided in the absorber 10 (see fig. 3) is disposed in the purge discharge pipe 17, but may be provided in the lower portion of the high-temperature liquid storage chamber 14 es. The absorber 10A is the same as the absorber 10 (see fig. 3) except for the above-described configuration.

In the absorber 10A configured as described above, the makeup water Ws is supplied to the low-temperature reservoir 14ps in the absorber 10A by the makeup water pump 86. The heated medium liquid Wq flowing into the low-temperature reservoir 14ps as the makeup water Ws flows through the preheating pipe 12p to reach the relay reservoir 14pm, changes its flow direction in the relay reservoir 14pm, flows through the other preheating pipe 12p, and flows into the high-temperature reservoir 14 es. When the heating medium liquid Wq flows through the inside of the preheating pipe 12p, the concentrated solution Sa wetting and spreading on the outer surface of the preheating pipe 12p absorbs the heat of absorption generated when the evaporator refrigerant vapor Ve is heated. At this time, the heating medium liquid Wq flowing through the preheating pipe 12p does not evaporate although its temperature rises. Since the preheating pipe 12p in the present modification has a low temperature of the heating medium liquid Wq flowing inside and is disposed at the lowermost portion of the heat transfer pipe 12, the temperature of the concentrated solution Sa spread from above is further lowered, and a large amount of absorption heat can be efficiently absorbed from the concentrated solution Sa. The heating medium liquid Wq heated by the preheating pipe 12p flows into the high temperature liquid storage chamber 14es, while the heating medium liquid Wq from the gas-liquid separator 80 also flows into the high temperature liquid storage chamber 14es through the heating medium liquid pipe 82. By causing the heated medium liquid Wq from the gas-liquid separator 80 to flow into the high-temperature liquid reservoir 14es without flowing into the low-temperature liquid reservoir 14ps, the preheating pipe 12p is efficiently preheated without increasing the temperature of the heated medium liquid Wq flowing through the preheating pipe 12p, and the heated medium liquid Wq flowing from the high-temperature liquid reservoir 14es into the evaporation pipe 12e is increased in temperature, so that the heated medium liquid Wq is easily evaporated in the evaporation pipe 12 e. Further, since the absorber 10 is constituted by a plurality of paths (two paths) in which the preheating pipes 12p having different flow directions are arranged in the upper and lower directions, the installation area of the absorber can be reduced.

Next, an absorber 10B according to a modification will be described with reference to fig. 5. The absorber 10B is different from the absorber 10A (see fig. 4) in the following points. Similarly to the absorber 10 (see fig. 3), one of the water chamber forming members 14 is divided into the low-temperature liquid reservoir 14ps and the mixed fluid chamber 14ec by one partition plate 15, and the other is provided with no partition plate 15 and is formed as a high-temperature liquid reservoir 14es as a whole. In the absorber 10B, the low-temperature liquid storage chamber 14ps corresponds to a preheating pipe supply section, the high-temperature liquid storage chamber 14es also serves as a preheating pipe recovery section and an evaporation pipe distribution section, and the mixed fluid chamber 14ec corresponds to an evaporation pipe collection section. The absorber 10B is provided with a single preheating pipe supply section (low-temperature liquid storage chamber 14ps) and a single preheating pipe recovery section (high-temperature liquid storage chamber 14es), and the preheating pipe 12p is formed by a single path. In the absorber 10B, the water chamber forming member 14A forming the high-temperature liquid reservoir 14es is configured to gradually decrease the cross-sectional area between the tube plate 14Aj to which the heat transfer tubes 12 are attached and the inner wall 14Ag facing the tube plate 14Aj, from the position where the heated medium liquid Wq flows from the preheating tube 12p into the high-temperature liquid reservoir 14es toward the evaporation tube 12e disposed farthest away. In the absorber 10B, the preheating tubes 12p are horizontally arranged below and the evaporation tubes 12e are horizontally arranged above, respectively, and therefore the area of the horizontal cross section between the tube plate 14Aj and the inner wall 14Ag gradually decreases from below to above. Further, the tube sheet 14Aj corresponds to an evaporation tube installation wall. Further, a purge discharge pipe 17 provided with a purge discharge valve 17v is provided at a lower portion (typically, a bottom portion) of the high-temperature liquid storage chamber 14 es. The absorber 10B is the same as the absorber 10A (see fig. 4) except for the above-described configuration. Therefore, a makeup water pipe 85 is connected to the low-temperature liquid chamber 14ps, a heated medium liquid pipe 82 is connected to the high-temperature liquid chamber 14es, and an outflow pipe 84 is connected to the mixed fluid chamber 14 ec.

According to the absorber 10B configured as described above, the area of the horizontal cross section between the tube plate 14Aj and the inner wall 14Ag is configured to gradually decrease from below toward above, so that variation in the flow rate of the heating medium liquid Wq flowing from the high-temperature liquid storage chamber 14es into the evaporation tubes 12e can be suppressed. The configuration of the absorber 10B in which the horizontal cross-sectional area between the tube plate 14Aj and the inner wall 14Ag of the high-temperature liquid storage chamber 14es is gradually decreased can be applied not only to the absorber 10 in which the preheating pipe 12p is a single path (see fig. 3), but also to the absorber 10A in which the preheating pipe 12p is a plurality of paths (see fig. 4).

In the above description, the evaporation tube 12e is formed linearly, but may be formed in a U-shape as in the absorber 10C shown in fig. 6. In this case, the high-temperature liquid storage chamber 14es (evaporation tube distribution portion) and the mixed fluid chamber 14ec (evaporation tube collection portion) are formed inside the same water chamber forming member 14 via the partition plate 15. The water chamber forming member 14 is configured such that the high-temperature liquid storage chamber 14es is formed in a lower portion and the mixed fluid chamber 14ec is formed in an upper portion, and the medium W to be heated flows upward from below in the evaporation tube 12 e. The inside of the other water chamber forming member 14 is divided into two spaces by a partition plate 15, one of which becomes a low-temperature liquid storage chamber 14ps (preheating pipe supply section), and the remaining space functions as a protection space for protecting the bent portion of the evaporation pipe 12e, and does not flow into the heating target medium W. The evaporation tube 12e of this example includes two horizontal tube portions in two rows, and the opposite end portions of the high-temperature liquid chamber 14es (evaporation tube distribution portion) are connected by inversion in a U-shape to form an uninterrupted heat transfer tube. In addition to this configuration, the evaporation tube 12e may be formed in an S-shape having three rows of horizontal tube portions, and the opposite end portion of the high-temperature liquid chamber 14es and the end portion of the high-temperature liquid chamber 14es may be connected to each other by reversing the U-shape in the flow direction of the heat transfer tube in an uninterrupted manner. Alternatively, the evaporation tube 12e may be formed into an M-shape having four rows of horizontal tube portions, and the ends of the tube portions may be connected one by reversing the U-shape to form an uninterrupted heat transfer tube, or may be formed into a serpentine heat transfer tube having more rows of horizontal tube portions, and the ends of the tube portions may be connected one by reversing the U-shape to form an uninterrupted heat transfer tube. In either case, the evaporator is composed of a plurality of uninterrupted evaporation tubes 12e in which the ends of the horizontal tube portions are connected one by U-shaped inverted portions so as not to intersect with other evaporation tubes, and the high-temperature liquid storage chamber 14es (evaporation tube distribution portion) and the mixed fluid chamber 14ec (evaporation tube collection portion) are connected to the inlet and outlet of the evaporation tubes 12e, respectively. Further, fig. 6 shows an example in which the preheating pipe 12p is constituted by one path, but the evaporation pipe 12e may be formed in a U-shape in addition to the preheating pipe 12p constituted by a plurality of paths. In the example shown in fig. 6, the preheating pipe 12p is formed linearly, but the preheating pipe 12p may be formed in a meandering shape such as a U-shape.

In the above description, the evaporation tube 12e is disposed with its axis horizontal, but may be disposed with an upward gradient as in the absorber 10D shown in fig. 7, that is: the connection portion with the mixed fluid chamber 14ec is located at a higher position than the connection portion with the high-temperature liquid storage chamber 14 es. The upward gradient of the evaporation tube 12e may be determined within a range in which a desired absorption heat can be obtained, in consideration of the range of the absorption liquid S that wets and spreads on the outer surface of the evaporation tube 12 e. If the evaporation tube 12e is inclined upward, the medium-to-be-heated vapor Wv generated in the evaporation tube 12e is easily released from the mixed fluid chamber 14 ec. On the other hand, when the evaporation tube 12e is horizontally disposed, the range of the absorption liquid S that wets and spreads on the outer surface can be enlarged. Although fig. 7 shows an example in which the preheating pipe 12p is constituted by one route, the preheating pipe 12p may be constituted by a plurality of routes and the evaporation pipe 12e may have an upward slope. In the example shown in fig. 7, the preheating pipe 12p is disposed horizontally, but the preheating pipe 12p may have an upward slope or a downward slope. When the preheating pipe 12p is provided with a gradient, the gradient may be determined within a range in which a desired absorption heat can be obtained. Alternatively, the preheating pipe 12p may be formed in a meandering shape such as a U-shape.

In the above description, the makeup water pipe 85 is connected to the heating medium liquid pipe 82 or the low-temperature liquid storage chamber 14ps, but may be connected to the gas-liquid separator 80 so that the makeup water Ws merges with the heating medium liquid Wq in the gas-liquid separator 80. In this case, the heated medium liquid Wq in the gas-liquid separator 80 may be guided to the low-temperature liquid storage chamber 14ps, and a pump for pressurizing and conveying the heated medium liquid Wq may be provided in a pipe for guiding the heated medium liquid Wq in the gas-liquid separator 80 to the low-temperature liquid storage chamber 14 ps. In the case where the makeup water Ws flowing through the makeup water pipe 85 merges with the heated medium liquid Wq flowing through the heated medium liquid pipe 82 and is introduced into the low-temperature liquid reservoir 14ps, or in the case where the makeup water Ws is introduced into the low-temperature liquid reservoir 14ps and the heated medium liquid Wq in the gas-liquid separator 80 is introduced into the high-temperature liquid reservoir 14es, a pump for conveying the heated medium liquid Wq under pressure may be provided in the heated medium liquid pipe 82 for introducing the heated medium liquid Wq in the gas-liquid separator 80 into the high-temperature liquid reservoir 14 es.

In the above description, the case where the absorption heat pump 1 is a single-stage pump has been described, but the absorption heat pump 1 may be a multi-stage pump.

Fig. 8 illustrates a structure of the two-stage absorption heat pump 8. The absorber 10 and the evaporator 20 in the absorption heat pump 1 shown in fig. 1 of the absorption heat pump 8 are divided into a high-temperature absorber 10H and a high-temperature evaporator 20H on the high-temperature side, and a low-temperature absorber 10L and a low-temperature evaporator 20L on the low-temperature side. The high temperature absorber 10H has a higher internal pressure than the low temperature absorber 10L, and the high temperature evaporator 20H has a higher internal pressure than the low temperature evaporator 20L. The high temperature absorber 10H and the high temperature evaporator 20H are communicated at the upper part thereof so that the vapor of the refrigerant V in the high temperature evaporator 20H can move to the high temperature absorber 10H. The low temperature absorber 10L and the low temperature evaporator 20L communicate with each other at the upper portion thereof so that the vapor of the refrigerant V in the low temperature evaporator 20L can move to the low temperature absorber 10L. The heating medium liquid Wq is heated by the high temperature absorber 10H. The heat source hot water h is introduced into the low-temperature evaporator 20L. The low-temperature absorber 10L is constituted by: the refrigerant liquid Vf in the high temperature evaporator 20H is heated by the absorption heat when the solution S absorbs the vapor of the refrigerant V transferred from the low temperature evaporator 20L, thereby generating the vapor of the refrigerant V in the high temperature evaporator 20H, and the heating medium liquid Wq is heated by the absorption heat when the generated vapor of the refrigerant V in the high temperature evaporator 20H is transferred to the high temperature absorber 10H and absorbed by the absorption liquid S in the high temperature absorber 10H. In this way, in the absorption heat pump 8, the configuration around the absorber shown in fig. 3 to 7 is applied to the high temperature absorber 10H. Even in the case of an absorption heat pump having three or more stages, the configuration around the absorber shown in fig. 3 to 7 can be representatively applied to an absorber having the highest internal temperature and internal pressure.

In the above description, the medium to be heated W is supplied as the medium to be heated Wv to the use steam position outside the absorption heat pump 1, but may be the refrigerant V used in the heat pump cycle. In this case, the configuration around the absorber shown in fig. 3 to 7 can be applied to the low-temperature absorber 10L of the absorption heat pump 8 shown in fig. 8, in other words, to an absorber other than the absorber having the highest internal temperature and internal pressure.

Claims

1. An absorption heat pump comprising an absorber for causing a liquid of a medium to be heated to flow through a plurality of heat transfer pipes and for causing an absorption liquid to fall outside the heat transfer pipes, wherein the absorption heat generated when the absorption liquid absorbs vapor of a refrigerant is used to heat the medium to be heated flowing through the heat transfer pipes and thereby evaporate the medium to be heated in the heat transfer pipes,

the heat conductive pipe has:

a preheating pipe for introducing and heating the liquid of the medium to be heated to raise the temperature of the liquid; and

an evaporation tube for introducing and heating the liquid of the medium to be heated, which has been heated by the preheating tube, to evaporate the liquid,

arranging the evaporation tubes and the preheating tubes in such a manner that the absorption liquid falls in the order of the evaporation tubes and the preheating tubes,

the absorber has an outflow passage configured to: one end of each of the evaporation tubes is connected to an evaporation tube distribution portion that distributes the heated medium to the plurality of evaporation tubes, and the other end of each of the evaporation tubes is connected to an evaporation tube collection portion that collects the heated medium from the plurality of evaporation tubes, and allows the heated medium to flow out from the evaporation tube collection portion to the outside of the absorber,

the evaporation tube distribution portion and the evaporation tube collection portion are each constituted by one, and are constituted such that: the heated medium flowing through the respective evaporation tubes does not merge between the evaporation tube distribution section and the evaporation tube collection section,

the evaporation tube distribution section also serves as a preheating tube recovery section for recovering the heated medium heated by the preheating tube,

the structure is as follows: the heat received by the preheating pipe from the absorption heat becomes heat that heats the liquid of the heated medium flowing into the evaporation pipe distribution portion in a range that does not substantially include the vapor of the heated medium.

2. An absorption heat pump comprising an absorber for causing a liquid of a medium to be heated to flow through a plurality of heat transfer pipes and for causing an absorption liquid to fall outside the heat transfer pipes, wherein the absorption heat generated when the absorption liquid absorbs vapor of a refrigerant is used to heat the medium to be heated flowing through the heat transfer pipes and thereby evaporate the medium to be heated in the heat transfer pipes,

the heat conductive pipe has:

the absorption heat pump further includes:

a gas-liquid separator that separates a mixed fluid of the liquid and the steam of the heated medium flowing out of the outflow flow path into: vapor of the heated medium and liquid of the heated medium;

a circulating liquid flow path that guides the liquid of the medium to be heated in the gas-liquid separator to the evaporation tube distribution portion; and

and an introduction flow path that guides the liquid of the medium to be heated before being heated by the absorption heat to a preheating pipe supply unit that supplies the medium to be heated to the preheating pipe.

3. An absorption heat pump according to claim 1,

the total heat conduction area of the plurality of evaporation tubes is more than 1 time and less than 10 times of the total heat conduction area of the preheating tube.

4. An absorption heat pump according to claim 2,

5. An absorption heat pump according to claim 2,

6. An absorption heat pump according to any one of claims 1 to 3,

the preheating pipe comprises many routes, many routes are provided with respectively: a plurality of preheating pipe supply units for supplying the heating medium to the preheating pipes, and a plurality of preheating pipe recovery units for recovering the heating medium heated by the preheating pipes.

7. An absorption heat pump according to claim 4,

8. An absorption heat pump according to any one of claims 1 to 3,

the preheating tube is constituted by a path having: a preheating pipe supply unit that supplies the medium to be heated to the preheating pipe, and a preheating pipe recovery unit that recovers the medium to be heated by the preheating pipe.

9. An absorption heat pump according to claim 4,

10. An absorption heat pump according to any one of claims 1 to 3,

the evaporation tube distribution portion is configured to: the sectional area of the surface orthogonal to the evaporating pipe mounting wall between the evaporating pipe mounting wall on which the plurality of evaporating pipes are mounted and the inner wall facing the evaporating pipe mounting wall is as follows: the position of the heated medium flowing into the evaporation tube distribution portion gradually decreases toward the evaporation tube farthest from the preheating tube.

11. An absorption heat pump according to claim 4,

12. An absorption heat pump according to any one of claims 1 to 3,

the absorber has a purge discharge pipe that is provided at a lower portion of the evaporation pipe distribution portion and discharges the heated medium.

13. An absorption heat pump according to claim 4,