JP2008128306A - Air-temperature type liquefied-gas vaporizer and method for liquefied-gas vaporization - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable air-temperature liquefied-gas vaporizer and method for liquefied-gas vaporization which positively prevent a fracture such as cracks from occurring in a welded part by adopting the structure that a strain caused by temperature change is absorbed in a heat-transfer pipe-line itself as well as a decrease in vaporization performance by suppressing occurrence of unstable flow of gas-liquid two-phase flow in the heat-transfer pipe line for vaporizing the liquefied gas. <P>SOLUTION: The air-temperature type liquefied-gas vaporizer is provided with an up-and down bend heat-transfer pipe-line 2 comprising an up-and-down bend heat-transfer pipe-line 2a for vaporization for forming vaporization gas by vaporizing the liquefied gas through heat-exchange with air, and an up-and-down bend heat-transfer pipe-line 2b for heating through heat-exchange the vaporization gas formed in the up-and-down bend heat-transfer pipe-line 2a for vaporization. In the air-temperature type liquefied-gas vaporizer 1, a twisted-tape members 6 are inserted to be fixed in heat-transfer pipes 3 at least in the up-and-down bend heat-transfer pipe-line 2a for vaporization. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an air temperature type liquefied gas vaporizer for vaporizing and regasifying a low temperature liquefied gas such as liquefied natural gas (LNG) by using air (atmosphere) as a heat source at the time of use. It is about the method.

  Conventionally, as an example of this kind of air temperature type liquefied gas vaporizer, there is what was shown by JP, 2004-44750, A (patent documents 1), and this is explained using Drawing 11 and Drawing 12. FIG. 11 is a front view showing a conventional air temperature type liquefied gas vaporizer, and FIG. 12 is a sectional view taken along line II-II in FIG.

  11 and 12, the air temperature type liquefied gas vaporizer 51 has a plurality of evaporation units (parallel heat transfer conduits) 53 arranged in parallel at intervals in the front-rear direction (front-depth direction in FIG. 11). And a heating unit 54 in which a plurality of finned meandering pipes (vertical bending heat transfer pipes) 55 are arranged in parallel at intervals in the front-rear direction. The evaporation unit 53 includes a pair of manifold pipes 56 and 57 that are arranged in parallel with each other at an interval in the vertical direction and extend in the left-right direction, and the length direction of the manifold pipes 56 and 57 between the manifold pipes 56 and 57 ( 11 are provided with finned tubes (heat transfer tubes) 58 that are arranged at intervals in the left and right direction and whose upper and lower ends are welded to both manifold tubes 56 and 57, respectively. Therefore, the evaporation section 52 is configured by arranging a plurality of evaporation units (parallel heat transfer conduits) 53 in parallel in a direction orthogonal to the manifold tubes 56 and 57 and the finned tube 58.

  Both ends of the upper manifold pipe 56 of the evaporation unit 53 are closed by blind flanges 59. The left end of the lower manifold pipe 57 in the front half evaporation unit 53 and the left end of the lower manifold pipe 57 in the rear half evaporation unit 53 are connected to each inlet header pipe 61. A branch pipe 62 is connected to the inlet header pipe 61, and an inlet flange 63 is connected to the center of the branch pipe 62. The right end of the lower manifold pipe 57 is closed by a blind flange 64.

  The finned tube 58 of the evaporation unit 53 is made of, for example, an aluminum extruded profile, and a plurality of fins 58a extending in the vertical direction are integrally formed radially on the outer peripheral surface. In each evaporation unit 53, the fins 58a of the finned tubes 58 adjacent in the left-right direction are connected by connecting members 65 at both upper and lower ends. The connecting member 65 has, for example, an S-shaped cross section so that the upper and lower manifold pipes 56 and 57 can be absorbed when they expand and contract in the length direction due to the influence of heat.

  When the inner diameter of the lower manifold pipe 57 of each evaporation unit 53 is D and the inner diameter of the finned pipe 58 is d, the dimensions satisfy the relations D ≧ 30 mm, d ≧ 24 mm, and D / d ≧ 1.25. It has been.

  The heating unit 54 arranges the finned meandering pipes (vertical bending heat transfer pipes) 55 in parallel on the right side of each evaporation unit 53 so as to come to a position corresponding to the evaporation unit 53 in the front-rear direction. It is configured. Each finned meandering tube 55 is formed, for example, by connecting a plurality of straight tubular finned tubes (heat transfer tubes) 66 by U-bend tubes 67. The straight tubular finned tube 66 has the same configuration as the finned tube 58 of the evaporation unit 53, and the upper and lower ends of the fins 66 a of the adjacent straight tubular finned tubes 66 are connected by a connecting member 65. One end of each finned meandering tube 55 is connected to the right side of the rightmost finned tube 58 in the upper manifold tube 56 of each evaporation unit 53, and the other end is arranged below the heating unit 54. The outlet header pipe 68 extends in the front-rear direction. An outlet flange 69 is connected to the central portion of the outlet header pipe 68. Reference numeral 70 denotes a leg portion for supporting the air temperature type liquefied gas vaporizer 51.

  In the air temperature type liquefied gas vaporizer 51 having the above-described configuration, the liquefied gas stored in the storage tank is fed into the inlet header pipe 61 through the branch pipe 62 from the inlet flange 63 which is an inlet portion, and passes through the inlet header pipe 61. Then, it flows into the lower manifold pipe 57 of each evaporation unit (each parallel heat transfer pipe) 53. The liquefied gas that has flowed into the lower manifold pipe 57 is diverted to all the finned pipes 58 and is regasified by exchanging heat with the atmosphere (air) while flowing upward in the finned pipes 58. The gas flows into the finned meandering pipe (vertical bending heat transfer pipe) 55 of the heating section 54 through the upper manifold pipe 56 and exchanges heat with the atmosphere at a predetermined temperature while flowing in the finned meandering pipe 55. For example, it is heated to 0 ° C. or higher. The heated gas flows into the outlet header pipe 68 and is sent out from the outlet flange 69 serving as the outlet portion to the consuming equipment.

  Thus, this conventional air temperature type liquefied gas vaporizer 51 has D ≧ when the inner diameter of the lower manifold pipe 57 of the evaporation unit (parallel heat transfer pipe) 53 is D and the inner diameter of the finned pipe 58 is d ≧ D ≧ The dimensions are such that the relationships of 30 mm, d ≧ 24 mm, and D / d ≧ 1.25 are satisfied. Thereby, in each evaporation unit 53, by equalizing the flow of the liquefied gas from the lower manifold pipe 57 to each finned pipe 58, the amount of frost formation on each finned pipe 58 becomes uniform, and the evaporation performance is uniform. To improve the overall performance of the vaporizer. Further, by equalizing the flow of the liquefied gas from the lower manifold tube 57 to each finned tube 58 in each evaporation unit 53, the height of the liquid level in each finned tube 58 is also uniformed, and each finned tube The temperature difference of 58 becomes smaller. As a result, the amount of heat shrinkage of each finned tube 58 is made uniform, and large distortion is prevented from occurring in the welded portion of the upper and lower manifold tubes 56 and 57 with the finned tube 58.

  However, in the above-described conventional air temperature type liquefied gas vaporizer, the evaporation portion has parallel heat transfer pipes formed by welding the upper and lower end portions of the heat transfer tubes 58 to the upper and lower manifold tubes 56 and 57, respectively. Even if the dimensions of the inner diameter D of the lower manifold pipe 57 and the inner diameter d of the heat transfer pipe 58 are defined so as to satisfy the predetermined relationship, the upper and lower manifold pipes 56, 57 have fins. There is a limit to reducing the distortion generated in the welded portion with the tube 58, and this is not always sufficient.

JP 2004-44750 A (paragraphs [0005] to [0009], FIG. 1) Japanese Patent Publication No.56-48038 (full text)

  Therefore, the problem of the present invention is that it is possible to reliably eliminate the occurrence of breakage such as cracks in the welded portion by adopting a structure that can absorb the distortion caused by the temperature change in the heat transfer pipe itself. By suppressing the occurrence of unstable flow of gas-liquid two-phase flow in the heat transfer pipe line that vaporizes the gas, it is possible to prevent a reduction in evaporation performance, thereby providing a highly reliable air-temperature liquefied gas vaporizer and The object is to provide a method for vaporizing a liquefied gas.

  In order to solve the above problems, the present invention takes the following technical means.

  The invention according to claim 1 is the vaporization generated in the vertical bending heat transfer conduit for vaporization for generating the vaporized gas by vaporizing the liquefied gas by heat exchange with air, and the vaporization generated in the vertical bent heat transfer conduit for vaporization A vertical bending heat transfer pipe formed from a heating vertical bending heat transfer pipe for heating the gas by heat exchange with air is provided, and at least the (straight tubular) transfer of the vaporization vertical bending heat transfer pipe An air temperature type liquefied gas vaporizer characterized in that a twist tape member is inserted and fixed in a heat pipe.

  Invention of Claim 2 vaporizes the liquefied gas by the heat exchange with air, and produces | generates a vaporization gas, The vaporization produced | generated by the vertical bending heat-transfer conduit part for vaporization, and the said vertical bending heat-transfer conduit part for vaporization In the vaporization method of liquefied gas using a vertically bent heat transfer conduit formed from a vertically bent heat transfer conduit for heating gas by heat exchange with air, at least the above-mentioned vertically bent heat transfer conduit for vaporization In this heat transfer tube, a twisted tape member is inserted and fixed, and this is a method for vaporizing liquefied gas.

  The air temperature type liquefied gas vaporizer or the method of vaporizing liquefied gas according to the present invention includes a vertically bent heat transfer conduit that evaporates liquefied gas and a vertically bent heat transfer conduit that heats the vaporized gas. The heat transfer pipe section is formed, and the structure that can be expanded and contracted by the temperature change to absorb the strain (thermal stress) by the vertically bent heat transfer pipe itself, so each heat transfer pipe is welded to the upper and lower manifold pipes. Unlike those having parallel heat transfer pipes formed in this way, the occurrence of breakage such as cracks in the welded portion can be reliably eliminated. In addition, since the twist tape member is inserted and fixed in the heat transfer pipe of the vertical bending heat transfer pipe for vaporizing the liquefied gas, the gas-liquid two-phase flow flowing through the vertical bending heat transfer pipe for vaporization is It is possible to greatly suppress the occurrence of unstable flow, and to prevent a reduction in evaporation performance. Therefore, according to the present invention, it is possible to provide a highly reliable air temperature type liquefied gas vaporizer and a method for vaporizing a liquefied gas, in which there is no occurrence of breakage in the welded portion and no reduction in evaporation performance.

  Hereinafter, the present invention will be described in more detail. The air temperature type liquefied gas vaporizer of the present invention includes a vertically bent heat transfer conduit for vaporizing liquefied gas by a vertically bent heat transfer conduit, and a vertically bent heat transfer for heating for heating the vaporized gas. A heat pipe section is formed. In this case, it is necessary to prevent an unstable flow of the gas-liquid two-phase flow as much as possible in the vertical bending heat transfer pipe portion for vaporization through which the gas-liquid two-phase flow flows.

  Here, generally, the unstable flow of the gas-liquid two-phase flow in the vertically bent pipe will be described. FIG. 10 is a diagram for explaining the unstable flow of the gas-liquid two-phase flow in the vertically bent pipeline.

  In general, when a gas-liquid two-phase flow flows through a vertically bent pipeline, the direction of the buoyancy of bubbles (gas) in the ascending path and the descending path is opposite to the flow direction of the gas-liquid two-phase flow, The flow pattern of the gas-liquid two-phase flow that flows through the up and down bent pipes is very complicated due to the stagnation of bubbles in the vent part) and the descending path. Then, the flow mode in which unstable flow of gas-liquid two-phase flow occurs will be explained. Although the slag flow is in the ascending path, the falling liquid film flow and the slag flow are alternately generated in the descending path. . In this case, from the state of the falling liquid film in the descending path as shown in FIG. 10A, the liquid is accumulated in the lower part of the air column as shown in FIG. Since the differential pressure between the head of the ascending path and the descending path decreases, the liquid column is swept into the ascending path at a certain moment. As a result, air columns are formed again in the descending path. In this manner, the flow of (a) and (b) in FIG. 10 is repeated, thereby causing a large flow artery movement and a differential pressure pulsation.

  In the vertically bent heat transfer pipe section for vaporization in the air temperature type liquefied gas vaporizer, vaporization of the liquefied gas is mainly performed by slug flow (Slug Flow: large bubbles (gas slag) satisfying the flow path cross section) and small bubbles. Liquid flow containing liquid (liquid slag) alternately, churn flow (churn flow: the flow of gas slag is long and the sea surface is pulsating, and the liquid slag contains many bubbles. And the flow of gas-liquid two-phase flow (the boundary with the gas slag is unclear), and the gas flowing in the vertically bent heat transfer pipe section for vaporization due to the uneven distribution of the gas section An unstable flow will occur in the liquid two-phase flow. Therefore, in the air temperature type liquefied gas vaporizer of the present invention, the vertical bending heat transfer pipe for vaporization is formed by inserting and fixing a twist tape member which is a spiral member in the heat transfer pipe of the vertical bending heat transfer pipe portion for vaporization. The occurrence of unstable flow in the gas-liquid two-phase flow flowing through the section is suppressed.

  That is, by inserting and fixing the twist tape member in the heat transfer tube of the vertically bent heat transfer tube section for vaporization, the liquid is guided to the heat transfer tube wall by the centrifugal force by the twist tape member which is a spiral member. Stable vaporization is possible by avoiding a state in which only the gas exists in the heat pipe wall portion. In addition, at the top of the heat transfer tube in the vertically bent heat transfer tube where the gas flow rate is faster than that of the parallel heat transfer tube, if there is no twist tape member, a droplet entrainment state occurs in which the droplet and gas move together. Due to the presence of the member, the liquid is not blown up to the upper part of the heat transfer tube by being guided to and collided with the heat transfer tube wall. Similarly, even in the descending path of the vertical bending heat transfer pipe section for vaporization, the liquid is not led to the lower part of the heat transfer pipe by being led to the heat transfer pipe wall and colliding with it. In this way, it is possible to suppress the occurrence of an unstable flow of the gas-liquid two-phase flow in the vertical bending heat transfer pipe portion for vaporization that vaporizes the liquefied gas.

  In addition, the vaporization parallel heat transfer pipe formed by welding the heat transfer pipes to the upper and lower manifold pipes is different from the vertically bent heat transfer pipe in which a plurality of heat transfer pipes are connected in series while meandering. Since the liquefied gas was vaporized in each of the parallel heat transfer tubes, the flow rate was slow, and the friction pressure loss in the tubes was a very low value of about several tens of mmAq (0.0001 MPa). On the other hand, in the vertically bent heat transfer pipe, the flow velocity is about 10 times faster than the parallel heat transfer pipe, and the friction pressure loss in the heat transfer pipe is several hundred to several thousand mmAq (0.001 to 0.01 MPa). ) To occur. As a result, the friction pressure loss in each heat transfer tube becomes dominant, and the liquefied gas flow distribution among a plurality of (for example, 12 rows) vertical bent heat transfer conduits can be made uniform. Stable flow can be suppressed.

  Next, embodiments of the present invention will be described with reference to the drawings. 1 is a front view of an air temperature type liquefied gas vaporizer according to an embodiment of the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a cross-sectional view of the heat transfer tube in FIGS. It is a front view which abbreviate | omits this fin and shows the principal part of an air temperature type | mold liquefied gas vaporizer. In this specification, the term “aluminum” includes aluminum alloy in addition to pure aluminum.

  1 to 4, the air temperature type liquefied gas vaporizer 1 includes a plurality of books arranged in parallel in the front-rear direction (front-depth direction in FIG. 1, left-right direction in FIG. 2). In the embodiment, 12 rows of vertically bent heat transfer pipes 2 are provided. Reference numeral 11 denotes an inlet flange through which the liquefied gas is led from the liquefied gas storage tank through a pipe. Two inlet header pipes 13 made of aluminum are connected to the inlet flange 11 via an aluminum branch pipe 12, and each of the inlet header pipes 13 has six rows of vertically bent heat transfer pipes. A straight pipe 3a constituting the heat transfer pipe 3 at the head of the path 2 is connected by welding.

  In this embodiment, each of the vertically bent heat transfer pipes 2 is formed in a meandering shape (vertically bent shape) by welding and connecting 12 heat transfer pipes 3 (straight pipes 3a) in series with a U-shaped vent pipe 4. ing. In this embodiment, the liquefied gas is vaporized by heat exchange with air by the seven heat transfer tubes 3 and the six U-shaped vent tubes 4 from the top to the seventh to generate the vaporized gas. A vertically bent heat transfer pipe portion 2a for vaporization is formed (see FIG. 4). Further, the vaporized gas generated in the vertical bending heat transfer pipe section 2a for vaporization is heated by heat exchange with air by the eighth to twelfth heat transfer pipes 3 and the five U-shaped vent pipes 4. A vertical bending heat transfer pipe section 2b for heating is formed (see FIG. 4).

  The rearmost heat transfer pipe 3 of each vertical bent heat transfer pipe 2 (the rearmost heat transfer pipe 3 of the heating vertical bent heat transfer pipe section 2a) is welded to the aluminum outlet header pipe 14. . An aluminum outlet flange 15 is connected to the outlet header pipe 14. Gas that is regasified by the vertical bending heat transfer pipe portion 2a for vaporization and heated to, for example, 0 ° C. or more by the vertical bending heat transfer pipe portion 2b for heating, is sent to the consumption equipment through the outlet flange 15. It has become. Reference numeral 16 denotes legs for supporting the air temperature type liquefied gas vaporizer 1. 17 is an upper frame for supporting a heat transfer tube, and 18 is a lower frame.

  Next, the heat transfer tube 3 will be described. Each heat transfer tube 3 of the aluminum extrusion mold is integrally formed on a straight tube 3a extending in the vertical direction (vertical direction) and an outer peripheral portion of the straight tube 3a. Eight fins 3b extending in the longitudinal direction of 3a are provided, and the fins 3b are connected to each other at a vertical position of the straight pipe 3a via an inverted S-shaped aluminum joining plate 5.

  FIG. 5 is a perspective view of a cross twist tape member showing an example of the twist tape member according to the present invention (a part of the longitudinal twist tape member is shown in the longitudinal direction), and FIG. 6 is shown in the heat transfer tube of the vertically bent heat transfer conduit for vaporization according to the present invention. It is sectional drawing for demonstrating the cross twist tape member inserted and fixed.

  In each of the vertically bent heat transfer pipes 2 provided in the air temperature type liquefied gas vaporizer 1, at least the heat transfer pipe 3 (straight pipe 3a) of the vertically bent heat transfer pipe part 2a for vaporization is a spiral member. As an example of the twist tape member, a cross twist tape member 6 as shown in FIGS. 5 and 6 is inserted and fixed. In this embodiment, the top of all seven heat transfer tubes 3 constituting the vertical bending heat transfer tube portion 2a for vaporization and the five heat transfer tubes 3 constituting the vertical bending heat transfer tube portion 2b for heating. A cross twist tape member 6 is inserted into and fixed to the heat transfer tube 3.

  The cross-twist tape member 6 is an aluminum extrusion mold, inserted into the heat transfer tube 3 (straight tube 3a), and welded to the heat transfer tube 3 (straight tube 3a) tube wall at the upper end and lower end thereof. It is fixed. As can be seen from FIG. 5 and FIG. 6, four spiral space passages that spirally extend in the vertical direction are formed in the heat transfer tube 3 (straight tube 3 a) by the cross twist tape member 6. The gas-liquid two-phase flow flows through the cylindrical space passage. The fixing of the cross twist tape member 6 is not limited to fixing by welding, and appropriate fixing means such as fixing by caulking can be employed.

  The cross twist tape member 6 is inserted over almost the entire length of the heat transfer tube 3 (straight tube 3a) in the longitudinal direction. Moreover, the twist pitch P of the cross twist tape member 6 is, for example, 40 mm (180 ° twist pitch) (see FIG. 6).

  As described above, the air temperature type liquefied gas vaporizer 1 of the present embodiment is used for heating by heating the vertically bent heat transfer pipe portion 2a for vaporizing the liquefied gas and the vaporized gas by the vertically bent heat transfer pipe 2. Since the vertically bent heat transfer pipe section 2b is formed, and a structure in which the vertical bent heat transfer pipe 2 itself can absorb the strain (thermal stress) by expanding and contracting due to temperature change, the respective heat transfer pipes are transferred to the upper and lower manifold pipes. Unlike those having parallel heat transfer pipes formed by welding the hot tubes, it is possible to reliably eliminate the occurrence of breakage such as cracks in the welded portion. In addition, since the cross twist tape member 6 is inserted and fixed in the heat transfer tube 3 of at least the vertical bending heat transfer pipe portion 2a for vaporization, it is incapable of gas-liquid two-phase flow flowing through the vertical bending heat transfer pipe portion 2a for vaporization. It is possible to greatly suppress the occurrence of stable flow, and to prevent a decrease in evaporation performance.

  Next, experimental examples according to the present invention will be described. FIG. 7 is a diagram related to the present invention and is a diagram for explaining an experimental air temperature type vaporizer.

  As shown in FIG. 7, the heat transfer pipe 3 ′ with fins extending in the vertical direction and having an outer diameter of 25 mm, an inner diameter of 20.4 mm, and a length of 4850 mm is vertically bent and transmitted by four U-shaped vent pipes 4 ′. While constructing a heat pipe, an experimental air temperature type vaporizer was manufactured by inserting and fixing the cross twist tape member shown in FIGS. 5 and 6 in the five heat transfer tubes 3 ′. Liquefied nitrogen is vaporized and heated using an experimental air temperature type vaporizer equipped with this one row of vertically bent heat transfer pipes. It was investigated whether or not stable flow occurred. In this investigation, as shown in FIG. 7, the presence or absence of the unstable flow was determined by measuring the temperature of each part # 1 to # 21 in the vertically bent heat transfer pipe.

  FIG. 8 is a graph showing an example of an experimental result by the experimental air temperature type vaporizer shown in FIG. 7, and FIG. 9 is a graph showing an example of the experimental result.

  FIG. 8 is a graph showing the temperature of each part of # 1 to # 21 and # 57 of the vertically bent heat transfer pipe at the time of 4 hours after the start of operation at a flow rate of 84 kg / h in liquid nitrogen, The results are shown when there is a cross twist tape member (shown by a solid line) and when there is no cross twist tape member (shown by a broken line). As can be seen from the figure, in the case of no cross-twist tape member, a temperature reversal phenomenon occurred in part # 5 and part # 6, and an unstable flow of gas-liquid two-phase flow occurred in this part. Was recognized. On the other hand, in the case of the presence of the cross twist tape member, the temperature reversal phenomenon at the upstream portion and the downstream portion was not recognized.

  FIG. 9 is a graph showing the temperature of part # 5 and part # 6 measured over 240 minutes from the start of operation at a flow rate of 84 kg / h in liquid nitrogen, and (a) shows the case with a cross twist tape member. (B) shows the case without the cross-twist tape member. The graph of the part # 5 is indicated by a thin line, and the graph of the part # 6 is indicated by a thick line. As can be seen from FIG. 9 (b), in the case of no cross twist tape member, a temperature reversal phenomenon occurred, and it was recognized that an unstable flow of gas-liquid two-phase flow occurred. On the other hand, as can be seen from FIG. 9A, in the case of the presence of the cross twist tape member, the reverse phenomenon is not recognized, and the cross twist tape member can suppress the unstable flow of the gas-liquid two-phase flow. It could be confirmed.

It is a front view of the air temperature type liquefied gas vaporizer by one embodiment of the present invention. It is a side view of FIG. It is sectional drawing of the heat exchanger tube in FIG. 1, FIG. It is a front view which abbreviate | omits the fin of a heat exchanger tube and shows the principal part of an air temperature type liquefied gas vaporizer. It is a perspective view (a part is shown in the longitudinal direction) of a cross twist tape member which shows an example of a twist tape member concerning the present invention. It is sectional drawing for demonstrating the cross twist tape member inserted and fixed in the heat exchanger tube of the vertical bending heat exchanger tube part for vaporization which concerns on this invention. It is a figure concerning the present invention, and is a figure for explaining an experimental air temperature type vaporizer. It is a graph which shows an example of the experimental result by the air temperature type | formula carburetor for an experiment shown in FIG. It is a graph which shows an example of the same experimental result. It is a typical explanatory view for explaining unstable flow when a gas-liquid two-phase flow flows through a vertically bent pipe. It is a front view which shows the conventional air temperature type | mold liquefied gas vaporizer. It is the II-II sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Air-temperature type liquefied gas vaporizer 2 ... Vertical bending heat-transfer pipe line 2a ... Vertical bending heat-transfer pipe part 2b for vaporization 2b ... Vertical bending heat-transfer pipe part for heating 3, 3 '... Heat-transfer pipe 3a ... Straight pipe 3b ... Fin 4, 4 '... U-shaped vent pipe 5 ... Joint plate,
6 ... Cross twist tape member,
DESCRIPTION OF SYMBOLS 11 ... Inlet flange 12 ... Branch pipe 13 ... Inlet header pipe 14 ... Outlet header pipe 15 ... Outlet flange

Claims (2)

  Vaporization vertical bending heat transfer pipe section for generating vaporized gas by vaporizing liquefied gas by heat exchange with air, and heat exchange of vaporized gas generated in the vaporization vertical bending heat transfer pipe section with air A vertical bending heat transfer pipe formed from a heating vertical bending heat transfer pipe for heating by a twist tape member is inserted and fixed in at least the heat transfer pipe of the vertical bending heat transfer pipe for vaporization. An air-temperature liquefied gas vaporizer characterized by   Vaporization vertical bending heat transfer pipe section for generating vaporized gas by vaporizing liquefied gas by heat exchange with air, and heat exchange of vaporized gas generated in the vaporization vertical bending heat transfer pipe section with air In the method of vaporizing liquefied gas using a vertically bent heat transfer conduit formed from a vertically bent heat transfer conduit for heating by heating, at least a twist tape in the heat transfer tube of the vertically bent heat transfer conduit for vaporization A method for vaporizing a liquefied gas, wherein a member is inserted and fixed.

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