JP2951029B2 - Direct-fired high-temperature regenerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct-fired high-temperature regenerator (hereinafter, referred to as a regenerator) used for an absorption refrigerator or an absorption heat pump.

[0002]

2. Description of the Related Art As a regenerator used for an absorption type refrigerator such as a lithium bromide-water system, Japanese Patent Publication No. 53-26858 is known.
Japanese Patent Application Laid-Open Publication No. H11-139,055 discloses a technique for reducing overheating of a solution and corrosion of members.

In the regenerator proposed here, heat transfer fins are not provided on the heat-heating portion of the heat-side heat transfer surface, but heat transfer fins or irregularities are provided on the liquid-contact-side heat transfer surface of the strong heat portion. The heat of the heated portion is quickly dissipated to the solution in a relatively large area through the heat transfer fins to prevent film boiling and decompose due to overheating of the solution (generation of non-condensable gas) and overheating of the heat transfer surface. At the same time to solve the corrosion due to.

[0004]

However, in the regenerator having the above-described structure, the solution surrounded by the heat transfer fins has a tendency to be overheated locally because it is difficult for the solution to flow. For this reason, there has been a demand for the development of a regenerator in which the solution easily circulates without stagnation and does not cause inconveniences such as decomposition of the solution due to overheating and corrosion of the heat transfer surface.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and the gist of the present invention is to spray or vapor-deposit or deposit fine metal particles on the liquid-contacting heat transfer surface. Is formed on the porous heat transfer surface by a cavity formed by welding or machining, and the heat generated when gas or the like is burned in the furnace tube is efficiently transferred to the solution, causing the solution near the heat transfer surface to boil and the refrigerant vapor Is efficiently generated and separated to increase the solution concentration, efficiently radiate heat to the solution side to prevent overheating of the heat transfer plate itself, and alleviate the corrosive environment. Further, the heat transfer surface on the liquid contact side is formed on the porous heat transfer surface by spraying a nickel-chromium alloy having a linear expansion coefficient similar to that of iron on the base material of iron, and forming the heat transfer surface even when the temperature rises during use. This is to prevent the layer of the porous heat transfer surface from peeling off.

[0006]

[Function] Since the porous heat transfer surface has a large contact area with the solution,
The heat generated when gas is burned is efficiently transferred to the solution through the increased heat transfer surface, the solution is quickly heated and boils near the heat transfer surface, the refrigerant vapor is separated, and the solution is concentrated. You. Since the heat transfer surface itself efficiently radiates heat, overheating is prevented and the corrosive environment is alleviated. Moreover,
Since there is no heat transfer fin or the like that hinders the flow of the solution, there is no longer a stagnation region of the solution, and the solution is not overheated.

[0007]

Embodiment 1 A first embodiment will be described with reference to FIG. 1. 1 is a regenerator body, 2 is a furnace tube, 3 is a burner, 4 is a smoke tube,
5 is a chimney, 6 is a diluent inlet, 7 is a vapor outlet, and 8 is a solution outlet. Porous transfer is made to the liquid contact surface of the rear tube sheet 22 of the furnace tube return chamber 21 communicating with the furnace tube 2 at the back. A hot surface A is formed.

The porous heat transfer surface A has, for example, an average particle size of 35
A nickel-chromium alloy having a thickness of 30 μm is sprayed on the surface of the base material of iron at an average thickness of 30 μm, and its porosity is approximately 5%.

In the regenerator having the above-described structure, when a gas or the like is burned by the burner 3, a flame is formed toward the inner part of the furnace tube 2, and the high-temperature combustion gas is reversed in the furnace tube return chamber 21 toward the burner inlet. Then, it is discharged from the chimney 5 through the chimney 4 to the outside of the device. In this process, the solution in the regenerator body is heated by the heat of the flame to separate the refrigerant vapor and increase the solution concentration, but in the regenerator of the present embodiment, the rear pipe heated directly by the flame and strongly heated Since the liquid contact surface of the plate 22 is the porous heat transfer surface A, bubbles are easily generated in the holes of the heat transfer surface. As a result, the solution near the porous heat transfer surface A quickly boil.

At the porous heat transfer surface A, a strong ascending gas-liquid two-phase flow is generated by the pumping action of the bubbles which are generated one after another by the boiling and vigorously rise, and change the flow laterally after reaching the surface layer. Flows to the burner opening side. Then, under the rising gas-liquid two-phase flow, a low-temperature solution always flows in from the burner firing port side, and a large and strong convection over the entire device occurs, so that the solution stays in a specific area and becomes overheated. ,
It does not cause a problem that the concentration is abnormally increased and crystallization is caused to accelerate the corrosion of the member. The refrigerant vapor is separated, and a part of the solution flowing from the rear portion of the surface layer to the burner opening from the rear portion of the furnace tube is discharged from the solution outlet 8.

The rear tube sheet 22 ignited by the flame is:
Since heat is efficiently radiated to the solution through the porous heat transfer surface A, the solution does not overheat. Further, the heat of the combustion gas is efficiently radiated to the solution via the porous heat transfer surface A, and the
Since the temperature at the time of flowing into the tube is sufficiently low, the corrosive environment of the smoke tube 4 is also alleviated. Therefore, the life of the device is significantly longer than that of the conventional device.

[0012]

Embodiment 2 In the regenerator of Embodiment 2 illustrated in FIG. 2, the porous heat transfer surface A is provided on the rear tube sheet 22 and the liquid contact surface of the furnace cylinder return chamber 21 is changed to the porous heat transfer surface A. Formed on the same porous heat transfer surface B2.

In this regenerator, when gas or the like is burned by the burner 3 as in the first embodiment, heat is efficiently exchanged not only on the porous heat transfer surface A but also on the porous heat transfer surface B. Boiling more vigorously than in Example 1 on the rear side of the furnace tube, and a strong circulating force is generated. For this reason, strong and large convection of the solution occurs over the entire apparatus. Further, since the amount of heat radiated from the combustion gas to the solution further increases, the temperature of the combustion gas flowing into the smoke tube 4 further decreases, and the corrosive environment on the smoke tube inlet side is further alleviated. Therefore, the life of the device is longer than that of the first embodiment.

[0014]

Third Embodiment A regenerator according to a third embodiment illustrated in FIG. 3 has a porous heat transfer surface C formed on the liquid contact surface of the smoke tube 4 on the furnace tube return chamber 21 side. The porous heat transfer surface C is formed on the surface of a base material (iron) by a stainless steel having an average particle diameter of 40 μm (for example, SUS).
304) is electrodeposited to an average thickness of 60 μm,
The porosity is approximately 10%.

In the present regenerator, the solution is effectively heated by the porous heat transfer surface C formed on the liquid contact surface of the smoke tube 4, and the boiling tube is vigorously generated in the vicinity of the solution. Since the heat is dissipated and the temperature is reduced, the corrosive environment of the smoke tube 4 is improved.

[0016]

Embodiment 4 In the regenerator according to Embodiment 4 illustrated in FIG. 4, a plurality of rib-shaped rectifying plates 23 are vertically attached to a liquid contact surface of a rear tube plate 22, and the surface of the rectifying plate 23 is machined. Thus, a porous heat transfer surface D having a cavity 24 is formed.

The porous heat transfer surface D is formed, for example, by machining a plurality of angled ridges 241 on one surface of the base material at appropriate intervals as shown in FIG. Is formed, and the notch 242 is formed by processing the tip so that the notch 242 is expanded by, for example, roll pressing. Moreover, the porous heat transfer surface D is
3 can also be formed by spraying metal particles on the surface.

In the present regenerator, the rising speed of the solution is increased by the rectifying action of the rectifying plate 23, and the heat is efficiently exchanged by the porous heat transfer surface D on the surface to activate the boiling. Great circulation effect. Further, since the rectifying plate 23 has a fin effect and the heat transfer area is remarkably increased, the amount of heat radiated from the combustion gas to the solution further increases, and the temperature of the combustion gas flowing into the smoke pipe 4 decreases, thereby reducing the corrosion environment of the member. Is remarkably alleviated.

[0019]

Fifth Embodiment A regenerator according to a fifth embodiment illustrated in FIG. 5 has a plurality of water pipes 25 provided vertically in a smoke pipe and a furnace return chamber 21.
A porous heat transfer surface E is provided on the liquid contact surface of the water pipe 25 on the side. The porous heat transfer surface E is obtained by spraying a metal compound, for example, alumina having an average particle diameter of 20 μm to an average thickness of 30 μm on the surface of the base material (iron), and has a porosity of approximately 10%.
It is.

In this regenerator, the boiling of the solution flowing in the vicinity of the porous heat transfer surface E becomes active, and the water tube 25 itself radiates heat efficiently to lower the temperature of the heat transfer surface. The environment is significantly improved.

Since the present invention is not limited to the above embodiment, the configuration and shape of the regenerator and the materials used can be changed as appropriate. As for the material, for example, nickel or aluminum may be used as the metal particles forming the porous heat transfer surface on a base material such as iron, and the metal compound may be a metal oxide such as titania or stabilized zirconia, or a nitride. A metal nitride such as aluminum or silicon nitride may be used. The particle diameter is 10 to 44 μm
m, the thickness is preferably about 30 to 60 μm.

[0022]

As described above, according to the regenerator according to the present invention, since the solution is heated and boiled effectively through the porous heat transfer surface, a strong circulating force is generated and a large convection occurs over the entire apparatus. Happens. For this reason, a part of the solution is not heated and crystallized or decomposed. Further, the heat in the furnace tube is efficiently radiated to the solution side through the porous heat transfer surface, and is not overheated, so that the corrosive environment of the heat transfer surface is reduced. Further, since the heating efficiency is improved, it is possible to reduce the size of the entire apparatus, and it is also applicable to a regenerator for high load combustion.

[Brief description of the drawings]

FIG. 1 is a partially cutaway explanatory view of a first embodiment.

FIG. 2 is a partially broken explanatory view of a second embodiment.

FIG. 3 is a partially cutaway explanatory view of a third embodiment.

FIG. 4 is a partially cutaway explanatory view of a fourth embodiment.

FIG. 5 is an explanatory sectional view of a fifth embodiment.

FIG. 6 is an explanatory view showing a step of forming a cavity.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Regenerator body 2 Furnace 3 Burner 4 Smoke tube 5 Chimney 6 Dilute liquid inlet 7 Steam outlet 8 Solution outlet 21 Furnace cylinder return room 22 Rear tube plate 23 Rectifier plate 24 Cavity 25 Water tube A Porous heat transfer surface B Porous heat transfer Surface C Porous heat transfer surface D Porous heat transfer surface E Porous heat transfer surface

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-48-63352 (JP, A) Jikken Sho 49-1100 (JP, Y1) (58) Fields investigated (Int. Cl. ⁶ , DB name) F25B 33/00

Claims (8)

(57) [Claims] In a direct-fired high-temperature regenerator having a furnace tube and a smoke tube, or a furnace tube and a liquid tube, a furnace tube return chamber communicating with a liquid transfer side heat transfer surface of a furnace tube rear tube plate and a furnace tube rear portion. Wherein at least one of the heat transfer surfaces on the liquid contact side is formed on the porous heat transfer surface by thermal spraying, vapor deposition or electrodeposition of fine metal particles. 2. A direct-fired high-temperature regenerator provided with a furnace tube and a smoke tube or a furnace tube and a liquid tube, wherein a heat transfer surface on a liquid side of a smoke tube or a water tube located on the furnace tube return chamber side has fine metal. A direct-fired high-temperature regenerator formed on a porous heat transfer surface by thermal spraying, vapor deposition, or electrodeposition of particles. 3. A direct-fired high-temperature regenerator equipped with a furnace tube and a smoke tube or a furnace tube and a liquid tube, wherein the surface of the rectifying plate vertically attached to the liquid-contacting surface of the rear tube plate of the furnace tube has a fine metal surface. A direct-fired high-temperature regenerator formed on a porous heat transfer surface by thermal spraying, vapor deposition, or electrodeposition of particles. 4. In a direct-fired high-temperature regenerator equipped with a furnace tube and a smoke tube or a furnace tube and a liquid tube, a furnace tube return chamber communicating with a liquid transfer side heat transfer surface of a furnace tube rear tube plate and a furnace tube rear portion. A direct-fired high-temperature regenerator characterized in that at least one of the liquid-contact-side heat transfer surfaces is formed on the porous heat transfer surface by a machined cavity. 5. A direct-fired high-temperature regenerator having a furnace tube and a smoke tube, or a furnace tube and a liquid tube, wherein a heat transfer surface on the liquid contact side of the smoke tube or the water tube located on the furnace tube return chamber side is machined. A direct-fired high-temperature regenerator characterized by having a cavity formed on a porous heat transfer surface. 6. A direct-fired high-temperature regenerator provided with a furnace tube and a smoke tube or a furnace tube and a liquid tube, wherein a surface of a flow straightening plate vertically attached to a liquid-contacting surface of a rear tube plate of the furnace tube is machined. A direct-fired high-temperature regenerator characterized by having a cavity formed on a porous heat transfer surface. 7. In a direct-fired high-temperature regenerator equipped with a furnace tube and a smoke tube or a furnace tube and a liquid tube, a heat transfer surface on a liquid contact side is made by spraying a nickel-chromium alloy onto an iron base material to form a porous body. A direct-fired high-temperature regenerator formed on the heat transfer surface. 8. A direct-fired high-temperature regenerator provided with a furnace tube and a smoke tube, or a furnace tube and a liquid tube, wherein the heat transfer surface on the liquid contact side is made of a nickel-chromium alloy having a particle diameter of 10 to 44 μm on an iron base material. 3
A direct-fired high-temperature regenerator formed on a porous heat transfer surface by thermal spraying to a thickness of 0 to 60 μm.