JPS60164099A - Ambient ground heating device for cryogenic underground structure - Google Patents

Abstract

PURPOSE:To improve the heating efficiency against the ambient ground of cryogenic underground structure by filling viscous substance between a protective tube inserted into a drilled hole and the inner wall of drilled hole while inserting a hot water tube into the protective tube. CONSTITUTION:Water permeable protective tubes 3 having many through-holes 3a are inserted into holes C drilled into outercircumferential ground A of cryogenic underground tank 1 while surrounding said tank 1 then granular material D such as fine stones is filled between the outercircumference of said tube 3 and the drilled holes C. While not water tube 9 for circulating hot water is inserted into said tube 3 to construct an ambient ground heating system for cryogenic underground tank.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating device for controlling and limiting freezing of the ground surrounding low-temperature underground structures, such as low-temperature underground tanks and low-temperature underground warehouses.

Conventional equipment of this type has a triple-pipe structure consisting of a double-pipe section through which hot water circulates, and a storage pipe with a sealed structure that is buried in the ground surrounding the underground structure and protects the double-pipe section. , the filler such as sand was torn horizontally between the protective tube and the double tube.

In this way, in the conventional device, only granular materials such as sand are filled between the protective tube and the double pipe section through which hot water circulates, resulting in poor thermal conductivity (and heating efficiency). In addition, when attempting to repair the double tube section of the heating section, sand or the like is filled between the double tube section and the protective tube, making it difficult to pull out the double tube section.

In order to eliminate such defects, if water is filled in addition to particulate matter between the double pipe section and the protection tube, there is a risk that the inner surface of the protection tube will corrode. In order to prevent corrosion on both sides, a corrosion protection device is required, which makes it uneconomical.

The present invention was proposed to solve these problems, and involves inserting a perforated protection pipe into an excavation hole installed in the ground surrounding a low-temperature underground structure, and connecting the outer periphery of the protection pipe with the excavation hole. The surroundings of a low-temperature underground structure characterized in that granular materials such as fine stones and gravel are laterally split between the inner wall of the hole and a hot water pipe is inserted into the protection pipe with a gap between the pipe and the same. This relates to ground heating equipment.

As described above, the surrounding ground heating device for a low-temperature underground structure according to the present invention involves inserting a perforated maintenance pipe into an excavation hole provided in the surrounding ground of a low-temperature underground structure, and drilling the outer periphery of the protection pipe. Since the space between the holes is filled with granular materials such as fine stones and gravel, groundwater enters into the protection pipe through the perforated part, and water from the hot water pipe inserted into the protection pipe with a gap from the protection pipe. Heat conduction is improved, and heating efficiency for the surrounding ground of low-temperature underground structures is improved. At this time, underground water is filtered by the granular material that is laterally split between the protection pipe and the excavated hole, and foreign matter is prevented from entering the perforated protection pipe.

Furthermore, according to the present invention, as described above, since groundwater enters the perforated protection pipe, there is no need to fill it with particulate matter.
When attempting to repair hot water pipes, the pipes can be easily accessed and removed.

Furthermore, according to the present invention, since the protection pipe is manufactured from a concrete pipe or the like, the problem of corrosion is eliminated, and corrosion prevention treatment only needs to be applied to the outer periphery of the hot water pipe.
The present invention has many advantages, such as improved economic efficiency.

The present invention will be described below with reference to the illustrated embodiments.

(1) is a low-temperature underground tank, (2) is an underground continuous wall, and the excavated hole (C) surrounding the tank (1) is made with concrete in the outer ground (A) of the tank (1). A water-permeable perforated protection tube (3i) having a large number of through holes (3α) made of steel, synthetic resin, etc. is inserted, and fine stones are inserted between the outer periphery of the protection tube (31) and the excavation hole (C). , granular materials such as gravel (D
) to split horizontally. Furthermore, a hot water pipe for circulating hot water is inserted into the protection pipe (3) to constitute a ground heating device around the low temperature underground tank.

As shown in Fig. 2, the hot water pipe has an outer pipe (4) and an inner pipe (
5), hot water flows through the inner pipe (5) as an outgoing path, the outer pipe (4) as a return path, and circulates through the return pipe (6) connected to the outer pipe (4).

In addition, insert several spacers (7) into the outer tube (4) and attach the protective tube (
3), and also serves as a guide member when the hot water pipe enters and exits.

Since the illustrated embodiment is configured as described above, the groundwater (B) in the ground (AJ) enters the protection pipe (31) through the through hole (3a), and enters the outer pipe (4). Since the gap is filled, the heat from the hot water pipe is efficiently transmitted to the surrounding ground (A). Also, by applying anti-corrosion treatment to the outer surface of the outer pipe (4), corrosion of the outer surface can be prevented. In the figure ( 8) is a corrosion-resistant treated layer.

FIG. 3 shows another embodiment of the present invention, in which hot water pipes (9) with a U-shaped pipe structure are used instead of the hot water pipes with a double pipe structure in the previous embodiment.
using one pipe (9α) for the outbound route and the other pipe (9α) for the outbound route,
Heat is transferred to the outer ground (N) of the low-temperature underground tank (1) by circulating hot water with the same pipe diameter using b) as the return path.

In the embodiment shown in FIG. 3, the hot water pipe is a U-shaped pipe, so that the flow velocity inside the pipe is constant, and the flow rate calculation,
Thermal calculations are easy to perform, and since the round trip path for hot water has the same diameter, there is no air accumulation at the top of the hot water pipe unlike in hot water pipes with a double pipe structure, eliminating the need for an air bleed device, and the round trip path is also open. Because of its structure, it is easy to manufacture, and there are no parts such as bolt tightening, making it possible to manufacture it with an entirely welded structure, which has the advantage of improving the reliability of the device.

In the drawings, parts equivalent to those of the above embodiment are given the same reference numerals.

Although the present invention has been described above with reference to embodiments, the present invention is of course not limited to such embodiments (and various modifications to the design may be made without departing from the spirit of the present invention). be.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing an outline of the surrounding ground heating device for a low-temperature underground tank according to the present invention, and FIGS. 2 and 3 are enlarged vertical cross-sectional views of the main parts of the device according to the present invention. 4 is an enlarged view of the left half and right half of the heating device, FIG. 4 is a view taken from the arrow jV-IV in FIG. 2, and FIG. 5 is an enlarged view taken from the arrow v-
■It is a figure. (1)...Low temperature underground tank, (3)...Storage, (
3a)...Through hole, (4)...Outer pipe, (5)...Inner pipe, (9)...Hot water pipe, (A)...Peripheral ground, (B
)...groundwater in the outer ground, (C)...excavation hole, F
D+: Granular materials such as fine stones and gravel. Agent Patent attorney Shige Okamoto 3 people outside of the text Figure 2 Figure 3 O Figure 40 5th

Claims (1)

[Claims] A perforated protection pipe is inserted into an excavation hole arranged in the ground surrounding the low-temperature underground structure, and granular materials such as fine stones and gravel are laterally split between the outer periphery of the protection pipe and the inner wall of the excavation hole. A ground heating device for a low-temperature underground structure, characterized in that a hot water pipe is inserted into a storage pipe with a space between the storage pipe and the storage pipe.