JPH0416067Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is based on liquefied natural gas (hereinafter referred to as LNG),
The present invention relates to an apparatus for vaporizing liquefied gases such as liquefied petroleum gas, liquid nitrogen, and liquid oxygen using the atmosphere.

(Prior technology) The vaporization equipment at LNG vaporization terminals includes a method in which an aluminum finch tube is installed vertically and contacts seawater, a method in which LNG is passed through a coil through hot water heated by underwater combustion, or an intermediate method such as propane. There are methods that indirectly vaporize using a medium, but these devices are becoming more complex due to the use of icing, combustion equipment, and intermediate media.

There are also air-temperature vaporizers that use vertical finch tubes to exchange heat with the atmosphere for LNG vaporization terminals in cities far from the coast, but these are economically-scale devices that keep the heat transfer area to a certain level. During normal vaporization operation, moisture in the atmosphere freezes on the finch tube due to insufficient heating by the atmosphere, and the device has to stop operating after about 4 hours and thaw the ice by sprinkling water. It is affecting work efficiency.

As another prior art, Japanese Utility Model Application Publication No. 59-175798 describes a heat recovery device for evaporation of liquefied gas which uses a heat pipe and is heated by an air flow. That is, a heat pipe condensing section is inserted through the peripheral wall into a vaporization tank into which liquefied gas is introduced, and air is circulated toward an evaporation section to vaporize the liquefied gas.

(Problem to be solved by the invention) However, in the device described in the above-mentioned Japanese Utility Model Application No. 9-175798, only the temperature difference between the atmospheric temperature and the evaporation section is transmitted through the heat pipe condensing section built in the vaporization tank. It is only used for evaporation of liquefied gas, and no consideration is given to the temperature difference between the low temperature inside the vaporization tank and the high temperature outside air.If this temperature difference is also used for evaporation of liquefied gas, thermal efficiency will be improved. As described above, conventional devices have problems in terms of thermal efficiency, and because the heat pipe condensing part is inserted in the diametrical direction of the vaporization tank, there are disadvantages such as a large amount of dead space inside the tank. Furthermore, due to the reduction in heat transfer due to the freezing of moisture in the atmosphere, operations were halted and ice melting operations were forced by water spraying.
There are many problems such as a shortened gasification operation time and a corresponding decrease in work efficiency.

(Means for solving the problem) In view of the above, the present invention utilizes the high temperature atmosphere outside the vaporization tank in the prior art to evaporate the liquefied gas kept at a low temperature inside the tank. The surface area of the tank is expanded using fins to actively increase heat transfer to the liquefied gas at ambient temperature, and the casing and heat pipe are made into a double tube structure to eliminate dead space, increasing the amount of heat transfer. The aim is to reduce the amount of ice formed, extend operating time, and improve work efficiency.

(Embodiment) Figures 1, 2, and 3 show an embodiment of the present invention, in which a heat pipe 1 is arranged, for example, in a vertical shape, and both upper and lower ends 2, 2' are sealed as usual. A working fluid such as Freon R-22 is sealed inside, and a heat dissipating section 3 for condensing the working fluid is in the shape of a bare tube and is housed in the casing through a bottom plate 5 of the casing 4 with a gap 6 in between. The casing 4 is provided with a liquefied gas inlet 7 and an outlet 8, and further has vertical fins 9 installed on the outside and exposed to the atmosphere. The casing 4 is preferably cylindrical so as to form a double pipe structure with the heat pipe 1 in order to eliminate dead space, and if a large number of grooves are provided on the outer surface of the heat pipe heat dissipation section 3, the heat transfer effect will be increased.

The heat receiving part 10 at the other end of the heat pipe 1 has vertical fins 9
is planted, exposed to the atmosphere, and the lower end 2'
is fitted and supported in a hole 12 of a mounting base 11, and the upper casing 4 is retained by a spacer 13 to maintain its position.

A plurality of the heat pipe type liquefied gas air heating devices described above are connected in series as appropriate depending on the vaporization capacity, but in this case, they are connected as a pair using the curved pipe 14 and connected to the downstream casing via the connecting pipe 15. If they are connected, the piping becomes simple, and moreover, this curved pipe 14 can participate in the vaporization of the liquefied gas.

FIG. 4 shows another embodiment, in which the heat pipe type liquefied gas air temperature vaporization device is installed horizontally and slightly inclined to facilitate the flow of the working fluid in the pipes, and has a configuration in which a plurality of heat pipes are stacked upward. An annular fin 16 is provided.

(Function) In the heat pipe type liquefied gas air temperature vaporizer having the above configuration, the low-temperature LNG introduced from the inlet 7 is heated to a temperature difference from the atmospheric temperature by the vertical fins 9 of the casing 4 exposed to the atmosphere. Sideways
The LNG is heated from the outside, while the heat pipe heat dissipation section 3 releases the latent heat of condensation of the working fluid through heat exchange with the LNG in contact with the outer surface of the tube, heating the LNG from the inside. more heated.

The working fluid heated through the vertical fins 9 by natural ventilation in the finned heat receiving section 10 of the heat pipe is evaporated in the pipe, and the generated steam is conveyed to the heat radiating section 3, where it is condensed as described above and then evaporated again. It is returned to the heat receiving section 10.

The LNG heated by heat transfer from both the inside and outside passes through the curved pipe 14 and enters a pair of adjacent air temperature vaporizers, where it is heated and then sequentially flows down through the connecting pipe 15. , LNG to be introduced
Although the operation of the tube group depends on the capacity of
In the latter stage, the vaporized gas is heated, and from the final outlet 17 it is supplied to the consumer at the normal operating temperature, for example, about 20°C. Of course, the heat pipe type liquefied gas air temperature vaporizer can be arbitrarily selected according to the vaporization capacity, such as the size and number of fins of the casing, the length of the heat pipe heat receiving part, and the number of fins. For this reason, when the heat pipe is arranged in a rigid manner, the fins are preferably vertical, and when the heat pipe is arranged horizontally, the fins are preferably annular. In addition, liquefied gas is not limited to LNG, but also liquid nitrogen, liquid oxygen,
Can be widely used for liquefied propane, liquefied butane, etc.

(Effect) In the present invention, the heat pipe has its heat dissipation part covered with a casing with fins with a gap in between, and fins are planted in the heat receiving part, and the casing with fins and the heat receiving part with fins are exposed to the atmosphere. Therefore, the liquefied gas introduced into the casing is heated from the outside through the casing wall surface and from the inside through the tube wall of the heat pipe heat dissipation section, and is heated from both the inside and outside sides. Compared to heating, although the device is more compact, the heat transfer area is approximately twice as large, and the heat transfer coefficient is approximately 3.75 times higher.If many grooves are provided on the outer surface of the heat pipe heat dissipation section, the heat transfer coefficient is further increased by approximately 3.75 times. It can be increased by 1.5-2.0 times.

Therefore, conventionally, when heating only from the inside, the amount of heating heat is insufficient, and moisture in the atmosphere freezes not only in the vaporization tank that houses the heat pipe heat dissipation section but also on the fins of the heat receiving section, significantly inhibiting heat transfer. Although complicated operations such as stopping operations and melting ice by sprinkling water are often required, the number of operations can be reduced, the vaporization operation time can be doubled, and efficiency is improved.

In addition, the narrower the gap, the higher the flow rate of the liquefied gas and the better the heat transfer, so if the casing and heat pipe heat dissipation part have a double pipe structure as shown in the figure, it is easier to form a narrow gap. Moreover, there is no dead space as seen in the prior art,
The effects are significant, such as alleviating the freezing of moisture on the outside of the fins due to the accumulation of liquefied gas.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is a partially cutaway side view, Figs. 2 and 3 are enlarged cross-sectional views taken along lines - and -, respectively, of Fig. 1, and Fig. 4 shows another embodiment. FIG. 3 is a side view in an example. 1... Heat pipe, 2, 2'... Both ends, 3...
...Heat radiation part, 4...Casing, 5...Bottom plate, 6...
...Gap, 7...Inlet, 8...Outlet, 9...Vertical fin, 10...Heat receiving part, 11...Mounting stand, 12...
Hole, 13... Spacer, 14... Curved pipe, 15
...Communication pipe, 16...Annular fin, 17...Final exit.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A heat pipe has a heat dissipating part covered with a casing with fins with a gap in between, and fins are planted in the heat receiving part, and the casing with fins and the heat receiving part with fins are exposed to the atmosphere. A heat pipe type liquefied gas air temperature vaporization device which heats and vaporizes the liquefied gas introduced into the casing gap from both the inside and outside by the casing with fins and the heat radiation part. (2) The heat pipe type liquefied gas air temperature according to claim 1, which is a utility model registered claim, in which casings each attached to a plurality of heat pipes are successively communicated at the tips and bases so as to form one flow path. vaporizer.