JP2002147979A - Piping structure for heat storage material unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently aggregate and line up heat storage material units in a heat storage tank used for an LNG cold energy system. SOLUTION: The system consists of a vertical supply pipe 11 for flowing down low temperature liquid, a branch line network 12 which is connected to the lower end of the pipe 11, a heat exchange piping group 13 which communicates with the network 12 and in which a plurality of the pipes are set up parallel to the pipe 11 from the pipe surface so as to have substantially the same height therewith for flowing up the low temperature liquid, a header 14 wherein the upper end of the piping group 13 is connected to individual portions for collection of the low temperature liquid, and a return pipe 15 which is connected to the header 14. The system except its upper part is embedded in a curing thermal storage material unit 10 of substantially narrow and long rectangular shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe structure of a heat storage material unit. The present invention relates to a piping structure of a heat storage material unit in which units can be arranged collectively.

[0002]

2. Description of the Related Art As means for effectively utilizing LNG energy,
An LNG cold energy utilization system is being planned. The LNG cold energy utilization system has not been actively used in the past.
G Large-scale cold heat storage tank and liquefied gas storage tank capable of storing heat up to ultra-low temperatures are provided in the system for the purpose of using cold energy with high efficiency. Used to liquefy and store other useful gases. Since the LNG cold energy utilization system is operated in the daytime operation mode and the nighttime operation mode, it experiences a heat cycle from room temperature to extremely low temperature in a one-day cycle. For this reason, a large temperature difference occurs inside, and therefore, when constructing a large-sized cold heat storage tank, it is necessary to establish various techniques such as a heat storage tank construction technique and heat shielding.

As shown in FIGS. 3 and 4, a cold heat storage tank constructed in a heat storage tank building of this LNG cold heat utilization system is composed of a plurality of heat storage material units 50 having a predetermined shape. Is mainly composed of a heat storage material aggregate in which the heat storage materials are aligned and arranged so as to contact vertically and horizontally. It is assumed that the scale has a plane area of 30 to 40 m square and a volume of about 20 m depth.

[0004] Each heat storage material unit 50 has an elongated rectangular parallelepiped shape in which a heat exchange pipe 51 is provided inside and a concrete 54 is filled as a heat storage material around the heat exchange pipe 51. The size of the heat storage material unit 50 is one side. It is 1m, about 20m high, and its outer surface is covered with heat insulating material. In FIG. 3, this heat storage material unit 50 is aligned and buried in an excavation space excavated into a predetermined shape surrounded by an underground continuous wall 52, and 64 (8 × 8 rows) plan views are shown. An example is shown in which a block 53 is constructed as a rectangular block, and a plurality of blocks 53 are assembled to form a cold / heat storage tank. As shown in FIG. 4, a heat exchange pipe 51 connected to each heat storage material unit 50 has a header 56 disposed above each unit.
A supply pipe 57 and a return pipe 58 are provided via (56A, 56B).

FIG. 5 (a) shows the L in the heat storage material unit 50.
It is the schematic sectional drawing which showed the piping example of the heat exchange piping 51 of the cold liquefied gas, such as NG. As shown in FIG.
The low-temperature liquid of the cryogenic liquefied gas sent through the inside of the heat storage material unit 50 at a predetermined liquid pressure through a liquid inlet side header 56A disposed above the heat storage material unit 50 has a lower end 51a.
Is sent into a large number of heat exchange pipes 51 piped over the entire height so as to form a U-shape. It is sent to the next process. With such a configuration, in each heat storage material unit 50, during operation, the low-temperature liquid in the heat exchange pipe 51 is transferred to the heat storage material 5 around it.
It is vaporized by heat exchange with 4.

[0006]

At this time, in the pipe of the heat storage material unit through which the low-temperature liquid flows, when the low-temperature liquid is vaporized in the pipe, it is expected that the flow path of the liquid flowing down will be blocked. For example, in a U-shaped heat exchange pipe as shown in FIG. 5 (a), the liquid flow is dispersed in a downwardly flowing pipe portion, so that there is a possibility that vapor lock occurs in a downwardly flowing low-temperature liquid. Is high. For this reason, there is a problem when applied to a structure such as an LNG pipe in which a change from a liquid phase to a gas phase may occur. Therefore, it is desirable that the flow of the low-temperature liquid is circulated so as to rise upward from below the pipe.

FIG. 5 shows a pipe designed from this viewpoint.
There is a heat exchange pipe shown in FIG. In other words, this heat exchange pipe 63 connects the supply pipe 61 to the lower end thereof along the side surface of the heat storage material unit 60, and enters the heat storage material unit 60 through the liquid inlet side header 62 disposed below the bottom 60a of the unit. Heat exchange pipes 6 arranged in parallel along the vertical direction
3 and supply the low-temperature liquid into the heat exchange pipe,
The liquid flows upward from the lower end in the pipe, and is collected by the return pipe 58 via the liquid outlet header 58 at the upper part of the unit. However, in this piping structure, the supply pipe 61 is installed on the side of the heat storage material unit,
It is necessary to install the heat storage material unit support base 64 at the bottom, and it is necessary to secure a work space therefor, and there has been a problem that the installation of the entire heat storage material unit and the workability of piping are reduced.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a piping structure of a heat storage material unit having a low-temperature liquid heat exchange piping which efficiently utilizes the space of the heat storage material unit. To provide.

[0009]

In order to achieve the above object, the present invention provides a vertical supply pipe for flowing a low-temperature liquid of a cryogenic liquefied gas, a branch pipe network connected to a lower end of the vertical supply pipe, and a branch pipe. A plurality of heat exchange pipes which communicate with the pipe network and are arranged in parallel from the pipe surface to stand in parallel with the vertical supply pipe until the height thereof is substantially equal, and which allows the low-temperature liquid to flow upward; The upper end of the group is connected to each part, the header for collecting the low-temperature liquid, and the upper part of the system consisting of the return pipe connected to the header, other than the upper part of the system, is embedded in the substantially elongated rectangular parallelepiped curable heat storage material. Features.

[0010] The vertical supply pipe is piped at a substantially central position on a plane in the curable heat storage material along a longitudinal direction of the curable heat storage material, and the branch pipe network is formed around the lower end of the vertical supply pipe. Preferably, the pipes are arranged radially.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the piping structure of a heat storage material unit according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view in which a part of the heat storage material 1 is cut away so that a pipe state in the heat storage material unit 10 can be understood. As shown in the figure, a supply pipe 11 for flowing a low-temperature liquid to the bottom of the heat storage material unit 10 in the heat storage material unit 10 and a pipe connected radially and / or circumferentially to the supply pipe 11 at the bottom. A bottom branch pipe network 12 that is integrally connected; a heat exchange pipe 13 that is connected to a predetermined position of the bottom branch pipe network 12 and that is arranged so that the pipe itself extends in the vertical direction of the heat storage material unit 10. A header 14 in which a plurality of heat exchange pipes 13 connected to the upper end of the heat storage material unit 10 are gathered, and a return pipe 15 for joining and returning the return flow from the header 14 are provided.

As shown in FIG. 1, the supply pipe 11 comprises a horizontal pipe 11A and a vertical pipe 11B bent at a right angle downward by an elbow 11a and vertically piped to the center of the plane of the heat storage material unit 10. Then, the low-temperature liquid supplied into the pipe via a compressor not shown flows down to the lower end of the heat storage material unit 10. In this embodiment, a stainless steel tube having a diameter of 150 mm and a thickness of 3 mm is used. As a tube material, a copper tube having high thermal conductivity, exhibiting a non-corrosive property in concrete, and having a high thermal conductivity other than stainless steel is suitable.

In this embodiment, the bottom branch pipe network 12 is
As shown in FIGS. 1 and 2A, a radial pipe 12A extending radially from the lower end of the supply pipe 11 in eight directions, and a triple circumferential pipe 12B connecting the radial pipes 12A in the circumferential direction. Each pipe is assembled by welding a stainless steel pipe in the same manner as the supply pipe 11.

Further, the lower ends of a plurality of heat exchange pipes 13 are connected to the upper surface of each pipe of the bottom branch pipe network 12 at a predetermined interval. As shown in FIG. 1, a part of the heat exchange pipe group 13 extends from the bottom branch pipe 12 to the upper end of the heat storage material unit 10, and the header 14 (FIG.
The low-temperature liquid that has been joined in (c) and rises in the heat exchange pipe 13 is collected in the header 14. At this time, FIG.
As shown in (b), at the intermediate position of the heat storage material unit 10, the heat exchange pipes 13 are arranged in the heat storage material 1 at substantially equal intervals. For this reason, the cold heat radiated from the heat exchange pipe 13 conducts heat uniformly to the surrounding heat storage material 1,
The entire heat storage material 1 can be uniformly cooled. As shown in FIG. 2C, the plurality of headers 14 are connected to a return pipe 15 provided above the heat storage tank. This return pipe 15
A part of the cryogenic liquid that has been heat-exchanged
It merges with the return flow from another heat storage material unit 10 and is supplied to the next process (not shown) in the cycle.

The above-mentioned main body of the supply pipe 11, the bottom branch pipe network 12 and the heat exchange pipe 13 are all assembled in advance in a mold for the heat storage material unit 10, and concrete as a heat storage filler is hardened around the body. The heat storage material unit 10 is filled and cured in the mold until a predetermined curing time has elapsed, and when the concrete reaches a predetermined strength, the heat storage material unit 10 is manufactured. As concrete, in addition to ordinary concrete, use of concrete mixed with non-corrosive metal-containing aggregates, slag, and the like is considered from the viewpoint of enhancing thermal conductivity. As described above, the heat storage material unit 10 has the heat exchange pipes 13 buried therein so that the outer shape becomes an elongated rectangular parallelepiped. Is formed, and a plurality of blocks are assembled to form a compact cold heat storage tank, and the volume of the heat storage tank can be minimized.

Note that the pipe network layout, the pipe diameter, the number of heat exchange pipes 13 and the like of the bottom branch pipe network 12 are set to one.
It is preferable to design according to the volume of the heat storage material unit 10 per unit and the required heat exchange heat quantity. At this time, in order to increase the heat exchange efficiency between the heat exchange pipe 13 and the heat storage material 1, it is preferable to provide a radiation fin around the pipe. It goes without saying that various pipes may be used as long as the pipes are made of a metal pipe having good thermal conductivity and non-corrosive properties in concrete.

[0017]

As described above, the heat exchange pipe can be efficiently buried in the heat storage material unit, and the heat storage material units can be efficiently aligned and assembled in the cold / heat storage tank. It is effective in design and construction such as later earthquake resistance. In addition, there is an effect that work under the heat storage material unit can be eliminated also in terms of maintenance management of the heat exchange piping equipment.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a piping structure of a heat storage material unit according to an embodiment of the present invention.

FIG. 2 is an end view and a cross-sectional view of the piping structure of the heat storage material unit shown along the arrows and the cross-sectional lines shown in FIG.

FIG. 3 is a schematic plan view showing an example of a cold heat storage tank.

FIG. 4 is a cross-sectional view of the cold heat storage tank shown in FIG. 3, taken along the line IV-IV.

FIG. 5 is a cross-sectional view showing an example of a conventional planned piping structure of a heat storage material unit.

[Description of Signs] 1 heat storage material 10 heat storage material unit 11 supply pipe 12 bottom branch pipe network 13 heat exchange pipe 14 header 15 return pipe

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoji Nishikawa 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Tadashi 1-2-3 Shibaura, Minato-ku, Tokyo Shimizu Corporation F term in the company (reference) 3E070 AA02 AA13 AB32 DA03 EA04

Claims (2)

[Claims] 1. A vertical supply pipe through which a low-temperature liquid of a cryogenic liquefied gas flows down, a branch pipe network connected to a lower end of the vertical supply pipe, and a plurality of pipes connected to the branch pipe network on a pipe surface, A heat exchange pipe group that rises in parallel with the vertical supply pipe until the height thereof is substantially equal to the low temperature liquid, and an upper end of the heat exchange pipe group is connected to each part to collect the low temperature liquid. A piping structure of a heat storage material unit, characterized in that a part other than an upper part of a system including a header and a return pipe connected to the header is buried in a substantially elongated rectangular parallelepiped curable heat storage material. 2. The vertical supply pipe is piped along a longitudinal direction of the hardenable heat storage material at a substantially central position on a plane in the hardenable heat storage material, and the branch pipe is provided around a lower end of the vertical supply pipe. 2. The net according to claim 1, wherein the net is radially piped.
The piping structure of the heat storage material unit described.