JPH08310592A - Early extinction facility structure in floating-roof reservoir - Google Patents

Abstract

PURPOSE: To provide an early extinction facility structure in a floating-roof reservoir which can be constructed with a simple structure at a low cost, while halogen is not used as fire extinguisher so that the extinguisher may not adversely effect natural environments. CONSTITUTION: A floating roof 12 is placed at an opening of a reservoir body 11 between its periphery and an inner side wall face 11A of the reservoir body 11 via a sealing member 20. A fire extinguisher chamber 23 is formed inside the sealing member 20, wherein nitrogen gas is sealed in the chamber 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing member between a floating roof and a side wall of a main body, which is used mainly for storing a liquid containing a volatile component and which has an upper opening. The present invention relates to an initial fire extinguishing equipment structure in a floating roof type storage tank that is arranged via a space.

[0002]

2. Description of the Related Art A floating roof type storage tank is generally used for mass storage of volatile liquids such as petroleum.

As shown in FIG. 3, which is a cross-sectional view of a schematic structure of a floating roof type storage tank, a storage tank of a floating roof type is provided inside a cylindrical storage tank main body 31 opening upward, and at a peripheral portion of a disk-shaped deck 32A. A floating roof 32 with a pontoon 32B is arranged,
The floating roof 32 is brought into close contact with the liquid surface of the stored liquid 40 stored in the storage tank main body 31 by the buoyancy of the pontoon 32B and floats to prevent evaporation from the liquid surface. A seal member 33 is provided on the outer peripheral edge of the pontoon 32B, and the seal member 33 is pressure-bonded to the side wall inner peripheral surface 31A of the storage tank main body 31 to maintain airtightness inside and outside the storage tank.

By the way, in the storage of a flammable liquid, there is a possibility that a flammable gas leaking from a seal part may catch fire and a fire may occur, and such a fire extinguisher or a fire extinguisher may be extinguished at an early stage. Equipment must be provided. FIG.
In the fire extinguisher of the storage tank shown in FIG. 1, a fire extinguisher pipe 34 is arranged in a ring shape along the seal member 33 on the upper side of the seal member 31, and a jet nozzle 35 directed to the seal portion is circumferentially arranged in the fire extinguisher pipe 34. A plurality of fire extinguishing tubes 34 are provided at predetermined intervals.
The fire extinguishing agent storage container 37 provided on the deck 32A is connected by a plurality of pipes 36 arranged radially. The ejection nozzle 35 is closed by a material that is melted by the heat of fire. In the fire extinguisher having this configuration, halon is used as a fire extinguishing agent, and when the seal part fires, the closed part of the jet nozzle 35 is melted and opened by the heat of the fire, so that the halon contained in the extinguishant container 37 is contained. Is ejected toward the fire site through the fire extinguishing pipe 34, the pipe 36, and the ejection nozzle 35, thereby extinguishing the fire.

[0005]

However, in the fire extinguisher having the above structure, the extinguishant container 3 on the deck 32A is provided.
7 and the fire extinguishing pipe 34 at the peripheral portion must be connected by a plurality of pipes 36, and a structure for obtaining a large buoyancy is required to levitate them, resulting in a complicated structure and an increase in manufacturing cost. It was a thing.

[0006] Halon, which is used as a digestive agent, is considered to have a higher ozone depleting ability than CFCs because it contains bromine. Therefore, it is regulated as an ozone depleting substance in the same manner as specified CFCs. There is a problem that it cannot be used in the future because it has been decided internationally that it will be completely abolished by the year.

The present invention has been made in view of the above problems, and can be constructed at a low cost with a simple structure.
It is an object of the present invention to provide an initial fire extinguishing equipment structure for a floating roof storage tank, which does not use halon as an extinguishing agent and does not adversely affect the natural environment.

[0008]

In order to achieve the above object, an initial fire extinguishing system structure for a floating roof type storage tank has a structure in which a floating roof seals between an upper opening of a storage tank main body and an inner surface of a side wall of the main body. In the floating roof type storage tank arranged via a member, the seal member is provided with a fire extinguishant enclosing space formed along the seal member by a heat-melting material at an upper portion thereof. It is characterized in that the fire extinguishing agent is enclosed in.

The extinguishing agent is nitrogen gas.

[0010]

According to the above construction, when the flammable gas leaking from the seal part burns to cause a fire, the seal member at the fire part melts and breaks, and the extinguishant sprays from the extinguishant enclosure space to extinguish the fire. To do.

Nitrogen gas as a fire extinguishing agent extinguishes the fire by filling the surroundings of the fire site with interruption of oxygen supply.
Since it is the main component of air, it does not adversely affect the environment.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a floating roof type storage tank equipped with an embodiment of an initial fire extinguishing system structure for a floating roof type storage tank according to the present invention, and FIG. 2 is a partially enlarged view of a seal portion thereof.

In the illustrated floating roof type storage tank 1, a floating roof 12 having a pontoon 12B at the peripheral portion of a disk-shaped deck 12A is arranged inside a cylindrical storage tank main body 11 opening upward. A seal member 20 is provided on the outer peripheral edge, and the seal member 20 is pressure-bonded to the side wall inner peripheral surface 11A of the storage tank body 11 to maintain airtightness inside and outside the storage tank.

The seal member 20 is a urethane foam 21.
The cross-sectional shape is formed to have a height substantially equal to the thickness of the outer peripheral edge of the pontoon, and is thicker in the radial direction than the distance between the outer peripheral surface of the pontoon and the side wall inner peripheral surface of the storage tank body, and the surface thereof is It is covered with the skin member 22.

Further, inside the uppermost portion in the height direction, there is provided a fire extinguishing agent chamber 23 as a space for extinguishing agent having a circular cross-section with a predetermined diameter.

The fire extinguishing agent chamber 23 extends along the entire circumferential direction of the floating roof along the extending direction of the seal member 20, and the circumferential direction is divided (isolated) into a predetermined length. Each extinguishant chamber 23 is a ventilation pipe 23 leading to the outside
A is provided.

The vent pipe 23A is provided with a valve 23B, which is normally closed and hermetically sealed.

Nitrogen gas is injected into the fire extinguishing agent chamber 23 through the ventilation pipe 23A and sealed at a predetermined pressure, and the pressure of the nitrogen gas is regularly inspected and always maintained above a predetermined pressure. .

In the seal member 23 having the above structure, the urethane foam 21 is elastically deformed, so that the pontoon 1 is formed.
2B is interposed between the outer peripheral surface of the storage tank body 11 and the inner peripheral surface 11A of the side wall of the storage tank main body 11, and the outer surface of the urethane foam 21 is pressed against the inner peripheral surface 11A of the storage tank main body 11 by the elastic restoring force to form the floating roof 12. Maintains airtightness with the storage tank main body 11.

If a flammable gas leaking from the seal part is ignited and a fire occurs, the heat of the skin member 22 of the seal member 20 at the site where the fire has occurred melts and damages the extinguishant chamber 23 to the outside. Communicate. As a result, the high-pressure nitrogen gas filled in the fire extinguishing agent chamber 23 is ejected toward the fire site, and the periphery of the fire part is filled with nitrogen gas to extinguish the fire.

In the present embodiment, the extinguishant chamber 23, which is the extinguishant filling space, is filled with nitrogen gas as the extinguishing agent, but the extinguishing agent is not limited to this and may be another inert gas. It may be present, and the normal state is not a gas but a liquid or a solid that produces an inert gas by the heat of fire. In the case of a gas fire extinguisher, it is conceivable that the fire extinguishing agent housing space is widely formed inside the seal member 20 and the elasticity due to the compressibility of the enclosed gas is used for the sealing pressure. Since the sealing pressure decreases due to the release of the gas, and the leakage of the flammable gas increases, it is not preferable to completely depend on the sealing pressure of the gas in the extinguishant filled space, and the sealing member 20 alone is the minimum seal. It must be configured to obtain pressure.

[0022]

As described above, according to the structure of the initial fire extinguishing system in the floating roof type storage tank according to the present invention, the fire extinguisher is simply enclosed in the extinguishant enclosure space formed in the seal member. According to the configuration, when a flammable gas leaking from the seal part burns to cause a fire, the seal member at the fire part is melted by heat, and the extinguishant can be ejected from the extinguishant enclosed space to extinguish the fire. Therefore, it is not necessary to provide a structure on the floating roof, and not only the fire extinguishing equipment but also the floating roof itself can be configured at low cost.

Further, by using nitrogen gas as the extinguishing agent, there is no adverse effect on the natural environment, it is easily available and can be constructed at low cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a semi-underground floating roof type storage tank floating to which an embodiment of an initial fire extinguishing equipment structure in a floating roof type storage tank according to the present invention is applied.

FIG. 2 is a partially enlarged view of the floating roof seal portion.

FIG. 3 is a cross-sectional view of a floating roof storage tank equipped with an initial fire extinguishing facility having a conventional configuration.

[Explanation of symbols]

 1 Floating Roof Storage Tank 11 Storage Tank Main Body 11A Side Wall Inner Surface 12 Floating Roof 20 Sealing Member 23 Extinguishant Chamber (Extinguishant Filling Space)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hirochi Setaka 3-2-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toyosu General Office

Claims (2)

[Claims] 1. A floating roof type storage tank, wherein a floating roof is disposed at an opening of a storage tank main body having an upper opening through a seal member between the main body and a side wall inner surface of the main body. A floating roof type liquid storage tank having an extinguishant enclosing space formed along the seal member by a heat-melting material, the extinguishant being enclosed in the extinguishant enclosing space. Initial fire extinguishing equipment structure in. 2. The initial fire extinguishing equipment structure in a floating roof liquid storage tank according to claim 1, wherein the extinguishing agent is nitrogen gas.