JPH04169790A - Open rack type vaporizer - Google Patents

Abstract

PURPOSE:To prevent bowing generated at a lower header tank by introducing liquefied gas from an upper header tank, sprinkling water from sprinklers arranged above a standing panel to vaporize the gas, and feeding down the evaporated gas from the lower tank. CONSTITUTION:The upper ends of fin tubes connected to the entire outer periphery of an upper header tank 2 are covered with a heat insulator 6 to be insulated. Overflowing water from a sprinkler 4 is first brought into contact with the insulator 6 under the tank 2, and then fed down on a heat exchanging panel 1. With such a structure, liquefied gas is introduced from the tank 2, heat exchanged with parallel flow of sprinkled marine water to be vaporized, and discharged from a lower header tank 3 to constitute a down-flow type vaporizer. Since the tank 2 and the vicinity are insulated, a temperature difference between the upper and lower surfaces of a tube does not occur, and hence bowing can be eliminated.

Description

[Detailed Description of the Invention] Field of Application This invention relates to an open rack type vaporizer for vaporizing liquefied natural gas, in which liquefied gas is introduced from an upper header tank of a heat exchange panel with a series of fin tubes, and water is sprinkled. This invention relates to a down-flow molded vaporizer that exchanges heat in parallel with a heated heat medium, and a down-flow open rack vaporizer that prevents the bowing phenomenon and calorie hunting phenomenon that occur in the header tank of conventional up-flow vaporizers.

BACKGROUND ART As shown in FIGS. 3 and 4, for example, an open rack type vaporizer has a fin tube in which a pair of fins protrudes in the diametrical direction and is arranged in the fin direction to form a single panel. A heat exchange panel (1) is constructed by providing header tanks (2×3) at the upper and lower ends, and a water sprinkler (4) is arranged above the heat exchange panel (1) by arranging a plurality of such panels in parallel.
This structure allows seawater, which is a heat medium, to flow down onto the surface of the heat exchange panel (1).

As shown in Fig. 3, the heat exchange mechanism of the conventional vaporizer described above is such that ultra-low temperature liquefied gas flows from the lower header tank (3) into each fin tube and is vaporized, and is then transferred to the upper header tank (2) as room temperature gas. This is a flow to be sent out, and is what is called an upflow.

In the upflow of an open rack type vaporizer, the lower header tank (3) has ultra-low temperature liquid in the lower part of the pipe, while the upper part of the pipe receives heat input from the water sprinkling from the heat source, so it has a lower temperature than the lower part. The temperature becomes high, which causes a temperature difference between the top and bottom of the tube, causing a bowing phenomenon as shown by the Wei line in Figure 3.

When such a bowing phenomenon occurs, the lower part of the fin tube, especially the part where the lower end of the fin is cut off during assembly to be welded to the header tank during assembly, becomes bent, and stress increases due to the change in shape caused by the fin cutting. There are durability issues such as the possibility of damage to the internal parts and equipment due to
In order to prevent this, weld overlay on the fin cut-out part (Actually, it is not fair).

20549 Publication) etc. are required.

In addition, in upflow, the heat input to the lower header tank (3) as described above causes the liquid inside the header to evaporate, especially at low flow rates with small loads, which causes a hunting phenomenon in the delivered gas flow rate and calories. There are problems that arise.

Summary of the Invention In view of the above-mentioned current situation, the object of the present invention is to provide an open rack type carburetor that can prevent the bowing phenomenon that occurs in the lower header tank and extend the life of the panel, and that has a simple structure and is easy to install. As a result of various studies, in order to prevent the low-temperature liquid inside the header tank from being affected by water spraying, we decided to use a down-flow type vaporizer that introduces the ultra-low temperature liquid into the upper header tank and sends room temperature gas to the lower header tank. The structure is simple and the heat exchange efficiency is excellent.
It was discovered that an open rack type vaporizer that eliminates the hunting phenomenon and has excellent durability can be obtained.

That is, the present invention comprises a heat exchange panel with fin tubes arranged in series and header tanks provided at the upper and lower ends, liquefied gas is introduced from the upper header tank, and water sprinklers are installed above each of the upright panels. This is an open rack type vaporizer that is characterized by a downflow system that vaporizes liquefied gas by sprinkling water and extracts the vaporized gas from a lower header tank.

In addition, in the above configuration, the present invention includes: a) inserting a sparge pipe having a plurality of upward spout holes into the upper header tank and introducing the liquefied gas so as to divide the flow evenly; and b) the entire upper header tank and its immediate vicinity. A heat insulating material is attached to the outer surface of the fin tube to keep it cool and block other heat input.Water can be sprinkled from the fin tube part with the insulating material attached to prevent freezing, and a spiral plate or spiral core is installed inside each C1 fin tube. This is an open rack type vaporizer characterized by inserting a turbulence promoting material such as turbulence promoting material to prevent free fall of the liquid.

DISCLOSURE OF THE INVENTION BASED ON DRAWINGS FIG. 1 is an explanatory front view of an open rack type vaporizer according to the present invention. FIG. 2 is a longitudinal side view showing the upper header tank and water sprinkler.

Structure As shown in FIG. 1, the open rack type carburetor according to the present invention has, for example, a fin tube with a plurality of pairs of fins protruding from the periphery arranged in a predetermined fin direction to form a single panel. Header tanks (2
Although not shown, the heat exchange panels (1) are suspended in a plurality of sub-rows, and each header tank is orthogonally connected to one manifold.

That is, the upper header tank (2) is orthogonally connected to the liquefied gas supply manifold, and the lower header tank (2) is orthogonally connected to the liquefied gas supply manifold.
3) is orthogonally connected to a manifold for deriving vaporized gas.

In addition, the upper header tank (2) has a sparge pipe (5) inserted therein which has multiple ejection holes facing upward, and distributes the supplied liquefied gas evenly to each fin tube of the heat exchange panel (1). be able to.

Although not shown, a turbulence promoting material is inserted into each fin tube of the heat exchange panel (1) to prevent the liquefied gas from falling and improve the heat exchange efficiency. Turbulence promoting materials include:
- A spiral plate made of twisted sheets or a spiral core made of a twisted cross-section rod can be used.

As shown in Fig. 2, the structure is such that seawater as a heat medium overflows from the water sprinkler (4) placed above the heat exchange panel (1) and flows down the surface of the heat exchange panel (1). The upper end of each fin tube connected to the entire outer circumferential surface of the tank (2) is covered with a heat insulating material (6) to keep it cool, and the water sprinkler (
4) The overflowing water first hits the insulation material (6) below the upper header tank (2) and then flows down the surface of the heat exchange panel (1).

Effects With this structure, the open rack type vaporizer according to the present invention introduces liquefied gas from the upper header tank (2), and while it falls through each fin tube of the heat exchange panel (1), the liquefied gas is sprinkled with water. It vaporizes by co-current heat exchange with seawater, and constitutes a down-flow vaporizer that is led out from the lower header tank (3).

By inserting the sparge pipe (5) in the upper header tank (2), the liquefied gas is evenly distributed in the heat exchange panel (1), and stable heat exchange performance can be obtained.

In addition, since the upper header tank (2) and its vicinity are kept cool, even if ultra-low temperature liquefied gas flows into the upper header tank (2), the area around the pipes will not receive any other heat input due to the cold insulation. Since the hunting phenomenon is eliminated and there is no temperature difference between the upper and lower surfaces of the tube, the bowing phenomenon can also be eliminated, and the durability of the entire vaporizer is significantly improved.

Furthermore, the upper header tank (2) and the heat exchange panel (1)
) Since cold insulation is installed on the upper part and water is sprinkled on the cold insulation part, freezing does not occur in the area near the water spraying, a good water sprinkling condition can be obtained, and stable heat exchange performance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory front view of a down-flow open rack type vaporizer according to the present invention. FIG. 2 is a longitudinal side view showing the upper header tank and water sprinkler. FIGS. 3 and 4 are a front view and a side view of a conventional up-flow open rack type carburetor. 1... Heat exchange panel, 2... Upper header tank,
3... Lower header tank, 4... Water sprinkler, 5...
・Sparge pipe, 6...insulation material.

Claims (1)

[Scope of Claims] 1 A heat exchange panel is constructed by arranging fin tubes and providing header tanks at the upper and lower ends, and liquefied gas is introduced from the upper header tank, and water sprinklers are respectively arranged above the upright panels. This open rack type vaporizer is characterized by a down-flow system that vaporizes liquefied gas by sprinkling water and extracting the vaporized gas from a lower header tank. 2. A sparge pipe with multiple upward spouting holes was inserted into the upper header tank to introduce liquefied gas, and insulation was attached to the entire upper header tank and the outer surface of the fin tube in its immediate vicinity to keep it cool. 2. The open rack type vaporizer according to claim 1, wherein water can be sprinkled from the fin tube portion, and a turbulence promoting material is inserted into each fin tube.