JPS59147902A - Device for heating liquefied thermal medium - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates to an apparatus for heating a fluid heat medium in a closed cycle. More particularly, the present invention relates to an apparatus for heating a cryogenic fluid, such as liquefied petroleum gas, to convert it from a liquid to a gaseous state.

Prior Art: In the past, cryogenic fluids were heated using natural draft radiant heaters. This type of heater has the disadvantage that sufficient heat transfer is difficult to achieve when the heat source is in the form of radiant energy. In most cryogenic fluid processing, process pipes drop below freezing and a layer of ice forms on the surface of the pipe. Ice has extremely low thermal conductivity. Therefore, radiant heaters are rarely used to date for heating cryogenic fluids.

Convection heaters are used to transfer heat by flowing the heated products of combustion over a group of process pipes (usually finned pipes) in which a cold fluid circulates. Convection heaters are typically fan recirculating,
Jet recirculation type.

Alternatively, an air-excess type is used. These types σ)
The heater was found to be effective compared to radiant heaters. However, these types had the disadvantage of being relatively expensive.

Submerged waste heat heaters have also been used in which the hot products of combustion are passed through water to form froth. In boiler heaters, heat exchange pipes that circulate cold fluid are immersed in water. Submerged waste heat heaters have two basic problems. That is, (1) high temperature products and water are brought into direct contact, which may contaminate the water and oxidize it; and (2) combustion occurs by overcoming the water head, that is, the pressure of the water. This type of heater typically requires a higher horsepower blowley than other types of heating systems.

The most efficient heaters to date are large tank indirect heaters. The calciner sends combustion gases into a pipe immersed in a water bath. The process coil is immersed above the combustion pipe in the same large tank. The heated water moves to the top and natural convection transfers the heat to the process pipe where the cold fluid circulates. Although this Type 0 heater has been successful to date, it is not efficient in terms of energy transfer. When I looked at it, it wasn't that high. In fact, the thermal efficiency in a standard unit was only about 70 factors.

Accordingly, it is an object of the present invention to provide an improved heater for heating cryogenic fluids such as liquefied petroleum gas (LPG). The present invention relates to an improvement in indirect type aquarium heaters and also has the advantages of aquarium type heaters since the combustion gases are passed through the combustion pipe.

The process coil, ie, the process pipe through which the cryogenic fluid passes, is immersed in a water bath and is never exposed to combustion gases. Furthermore, the present invention is superior to conventional systems in terms of thermal efficiency, reaching a value of 95%. In today's world where energy costs are soaring and fuel protection is becoming more important, the present invention has great significance in that it can dramatically reduce energy consumption.

More specifically, it is an object of the present invention to provide an apparatus for heating cryogenic fluids such as liquefied petroleum gas whose heat transfer efficiency, i.e. thermal efficiency, is significantly improved compared to conventional types of heaters. .

SUMMARY OF THE INVENTION: According to the present invention, an apparatus for heating a closed cycle liquid heat transfer medium, such as liquefied petroleum gas (LPG), is provided.

The device of the invention is in the form of a closed vessel, such as a horizontal tank. A combustor housing is provided within the tank and in communication with one end thereof. A liquid heat transfer medium, such as water, fills the tank around the incinerator housing. The combustor is used to provide thermal energy and has a fuel inlet and a combustion air inlet. The combustor also has a flame outlet that communicates with the interior of the combustor housing through an opening in the end wall of the tank.

A flue is connected to an end of the combustor housing opposite the combustor. A flue extends from within the combustor housing through a sealed opening in the tank, thereby venting the exhaust gas to the atmosphere. A liquid heat transfer medium heat exchanger is supported outside the combustor housing within the water tank and communicates into the tank through a sealed opening. A liquid medium to be heated, such as liquefied petroleum gas, is moved through a heat exchanger. Combustion heat within the combustor housing is transferred to the heat medium, water, and thereby to a heat exchanger positioned within the heat medium, water. In order to improve the thermal efficiency of the unit, ie to extract as much combustion heat as possible, a liquid transfer heat exchanger is positioned in front of the flue in the combustor housing. A liquid transfer type heat exchanger includes a number of heat transfer pipes.

The liquid heat carrier, water, in the tank is circulated through these heat transfer pipes, so that the heat of combustion of the combustion gases passing through the liquid transfer heat exchanger is extracted.

Examples: Hereinafter, a cryogenic fluid heating device according to the present invention will be explained in detail using the drawings.

1-6, a preferred embodiment of a heating device according to the present invention is illustrated. The heating device includes a sealed tank 10. The illustrated tank 10 has the shape of a horizontally placed cylinder. That is, the tank 1o is supported on the member 12 with its axis pointing horizontally.

Tank 10 has end walls 10A and 10B. On the first end wall 10A are an air population 16 and a fuel inlet 1.
A combustor 14 having 8 is supported. An opening 10C is provided in the tank 10.

Fuel and gas are mixed in the combustor 14 and the combustion gas is sent into the tank 10. A combustor housing 2o is positioned within the tank 1°.

The combustor housing 20 has a cylindrical shape,
and an end wall 2OA common to the end wall 10''A of the tank 1o.
have. Opposite end wall 20 of the combustor housing
At position B, there is an opening 20 communicating with the flue chamber 22.
C is provided. In the flue chamber, “Tank 1
A flue 24 extending through the opening 10D in a sealed manner is connected thereto. Combustion heat from combustor 14 heats the interior of combustor housing 20 and combustion gases are exhausted through flue chamber 22 to flue 24 and to the atmosphere.

A liquid transfer heat exchanger 26 in the form of a looped finned pipe is positioned within the flue chamber 22 . A horizontal perforated distribution pipe 28 is positioned above the combustor housing 2o. The dispersion pipe 28 is
It is connected in series to a liquid transfer heat exchanger 26.

The inside of the tank 10 is filled with 3° of a heat exchange medium such as water. In order to extract maximum heat from the combustion of the fuel, water is drawn off through a pipe connected to the lower end of the tank 1o and pumped by a pump 34 through a pipe 66 connected to the fluid transfer heat exchanger 26. It is passed through and circulated. The circulated water passes through a heat exchanger 26 and is discharged through holes in a distribution pipe 28.

A liquid heat medium type heat exchanger 68 is positioned in an upper portion inside the tank 10 . In the illustrated embodiment, the liquid heat exchanger filter 8 has the form of a horizontally arranged finned pipe 40 extending through the end wall 10B of the tank 10. As previously mentioned, the liquid medium to be heated, such as a cryogenic fluid such as liquefied petroleum gas (LPG), passes through the length of the finned pipe 40 and exits the tank 10. The liquid to be heated is always confined within the liquid heat medium heat exchanger 38, and this liquid medium to be heated does not come into contact with the heat transfer medium 60 in the tank 10. In this manner, no contact occurs between the combustion gases confined within the combustor housing 20 and the liquid heat transfer medium heat exchanger 38. Combustion to liquid heat medium type heat exchanger 6 in the combustor housing 20
All of the heat transfer to the heat transfer medium 30 takes place as described above (in the form of water).
is the combustor housing 20. Heating is caused by contact over a large area of the flue chamber 22 and flue 24. Heater) All combustion heat not absorbed in the pufferfish 20 is heat exchanged by the liquid transfer type heat exchanger 26 when the combustion gas moves through the liquid transfer type heat exchanger 26 to the flue 24. This dramatically increases the thermal efficiency of the unit. In practice, thermal efficiencies of up to 95 inches have been achieved.

Heat transfer from the combustion heat to the cryogenic fluid via the liquid transfer heat exchanger 68 is accomplished by circulating water through the pump 34 to extract heat from the liquid transfer heat exchanger 26 to improve heat transfer. This is done by discharging it from the dispersion pipe 28. In this manner, by circulating the water and discharging it through the perforated distribution pipe, turbulence is created around the liquid heat transfer medium heat exchanger 68. Further, suitable operating parameters are used to control the amount of heat transfer medium 60, water, circulated by pump 64, such that the water is at least partially converted to steam within liquid transfer heat exchanger 26. You can also make it so that This steam is discharged through a perforated distribution nozzle 28. This further agitates the water surrounding the liquid heat transfer medium heat exchanger 38 and increases the efficiency of heat transfer from the liquid heat transfer medium to the cold fluid flowing within the finned pipes 40. A cryogenic liquid, such as liquefied petroleum gas, absorbs heat when it passes through heat exchanger 38 and is converted from liquid to gas. The unit emits gas and can therefore be used as a gaseous fuel, eliminating the need for cryogenic storage. Therefore, the heating device that achieves the above-mentioned object of the present invention provides a low temperature fluid heating means in which the efficiency of heat transfer from combustion of fuel to low temperature fluid is greatly improved. Furthermore, the heating device according to the invention has the advantage that the entire heat transfer takes place via the liquid heat transfer medium 30. The contact between the products of combustion and the heat transfer medium 60 is completely free (and therefore free of contamination and without the need for displacement or chemical treatment).

Referring to FIGS. 4 and 5, another embodiment of the present invention is illustrated. This embodiment is basically the same as the embodiment shown in FIGS. 1-6, except that the arrangement of the liquid transfer heat exchanger is different. In this embodiment, the heat transfer medium 30 is caused to flow through the liquid transfer heat exchanger 26A by natural convection, as opposed to the use of a pump as in the first embodiment. For this reason, the liquid transfer heat exchanger 26A takes the form of a number of finned pipes 42 arranged vertically within the flue chamber 22. Each finned pipe 42 communicates with the top and bottom of the flue chamber through an opening. Therefore, the heat transfer medium 60 is transferred to the finned pipe 42
can freely pass upwards through the As the combustion gases flow through the heat exchanger 2.6A and the finned pipe 42, this heat is transferred to the water therein, causing the heated water to rise and cause natural convection. being done.

In yet another embodiment, the outlet vibrator 3 of the pump 64
(S'A can also be directly connected to the distribution pipe 28A. The pump 64 circulates the heat transfer medium from inside the tank 1o and discharges it below the liquid heat medium heat exchanger 68. increases the agitation of the heat transfer medium and improves the efficiency of heat transfer to the cold fluid flowing within the heat exchanger 68.

Each of the embodiments of the present invention described above achieves extremely high thermal efficiency by maximizing the effective heat from the combustion gas in the combustor 20. Most of the remaining heat is extracted by liquid transfer heat exchanger 26 or 26A and transferred to heat transfer medium 30.

Although the invention has been described with some particularity and with reference to the accompanying drawings, it will be obvious that various modifications and changes may be made therein without departing from the spirit of the invention.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a device for heating a closed cycle liquid heat transfer medium according to the present invention. FIG. 2 is a cross-sectional view taken along line 2--2 in FIG. FIG. 6 is a cross-sectional view taken along line 6--6 in FIG. FIG. 4 is a longitudinal sectional view of another embodiment of the device for heating a closed cycle liquid heat medium according to the present invention in which the liquid transfer heat exchanger uses natural convection. FIG. 5 is a cross-sectional view taken along line 5--5 in FIG. 4. 10...Tank 10A, 10B...End wall 10C...Opening 12...Support member 14...Combustor 16...Air inlet 18
... Fuel population 20 ... Combustor no. 22 ... Flue chamber 24 ... Flue 26.
...Liquid transfer type heat exchanger 28...Perforated distributed vibro 0...Heat transfer medium Filter 4...Pump 68...
・Liquid heat medium type heat exchanger (4 people)

Claims (1)

[Scope of Claims] (1) An apparatus for heating a liquid heat exchange medium in a closed cycle, comprising a sealed tank having the liquid heat exchange medium inside; a combustor housing having a portion immersed in said liquid heat exchange medium; a combustor having a fuel inlet, a combustion air inlet, and a flame outlet communicating with the interior of said combustor housing; spaced apart from said flame outlet; a flue connected to the combustor housing at a location, the flue extending sealingly through the tank wall and communicating with the atmosphere; including inlet and outlet vibes sealingly extending through the tank wall; a liquid heat transfer medium heat exchanger comprising at least one elongated horizontal pipe within the upper portion of the tank and supported externally of the combustor housing; the sinterer flame outlet within the combustor housing; and said flue, having an inlet and an outlet sealingly penetrating at least said incinerator housing wall, and comprising means for circulating a liquid heat exchange medium therethrough. a liquid transfer heat exchanger; a pump having an inlet and an outlet communicating with the tank; and receiving a flow of liquid heat exchange medium from the pump;
the underside of said liquid heat transfer medium heat exchanger, comprising at least one elongated horizontal perforated pipe connected to discharge and discharging a sparge pipe positioned parallel thereto; (2. The device according to claim 1, wherein the liquid heat medium type heat exchanger is an elongated horizontal finned pipe. (3) The apparatus of claim 1, wherein the combustor housing comprises a horizontally disposed tank having the combustor outlet at one end and a flue chamber extending therefrom at the other end. and connected to the flue chamber/bar, the liquid transfer heat exchanger being positioned within the flue chamber. (4) A device according to claim 3. In the apparatus, the liquid transfer heat exchanger comprises a number of pipes positioned within the flue chamber, each pipe having a lower inlet opening and an upper outlet opening communicating with the liquid heat exchange medium. (5) The device according to claim 1 is heated at °C.
The liquid transfer heat exchanger comprises a plurality of vertical pipes, each pipe having a lower inlet end communicating with the flue chamber through the opening and an upper outlet end. Device.