JPS627071B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention is a floating roof type tank for oil storage, etc., which cools the floating roof by discharging water from the upper edge of the tank side plate in response to a fire outbreak. This invention relates to a heat-insulating structure, in particular, a plurality of ring-shaped aquifer grooves are provided in a descending manner toward the center on the upper surface of a downwardly sloping concave-shaped upper plate provided on the bottom plate of a floating roof to prevent overflow. This invention relates to a heat-insulating structure in which the water dissipated from the upper stage overflows through a weir to minimize the amount of water for cooling.

<Prior art> Storage tanks for petroleum, etc. cannot be built with unlimited large capacity from end bases due to their structural limitations, and therefore, in most cases, multiple tanks are installed in groups, as is generally seen in petroleum complexes. It is.

Fire is the most worrisome accident in tanks, and explosions caused by fires are a serious problem, so set intervals are set and prescribed disaster prevention equipment is installed.

By the way, there are various types of seed storage tanks, but so-called floating roof tanks are becoming widely adopted because of their advantages in structure, operating conditions, cost, etc.

Therefore, it goes without saying that the seed floating roof tank is also equipped with disaster prevention equipment, including not only the set spacing between adjacent tanks, but also the installation of water curtains between the tanks and the installation of water curtains on the side walls of the tank. In addition to having a radiant heat structure, such as by applying reflective paint, it also cools the floating roof by discharging water to remove the heat of vaporization as a measure to prevent ignition from the floating roof and to prevent pontoon foam seals from catching fire. It has a structure.

<Problems to be Solved by the Invention> However, in order to cool a floating roof using diffused water, the entire surface of the floating roof must be uniformly cooled by spray heads, which requires a large number of spray heads to be installed and increases the water pressure. This has the disadvantage that the pumping facility becomes complicated, and as a result, the amount of water used increases considerably, so there is the disadvantage that the cost is not cheap, and securing space for the facility and managing the equipment are complicated. There was a problem.

When the entire surface of the floating roof is covered with water and cooled, the floating roof sinks into the stored liquid, which increases the load on the roof.
As a result, there was a problem that in the event of a fire, the entire tank would catch fire.

Therefore, it was not possible to supply cooling water to the entire floating roof.

<Object of the Invention> The object of the present invention is to solve the technical problem of the disaster prevention structure of the floating roof tank based on the above-mentioned prior art, and to solve the problem of the disaster prevention structure of the floating roof tank based on the above-mentioned prior art. In the energy industry, a multi-stage ring-shaped aquifer is installed to collect water, utilize precipitation, reduce the amount of water aquifer, and simplify the facility so that it can fully fulfill the disaster prevention function. It is an object of the present invention to provide an excellent thermal insulation structure for floating roof tanks that will benefit the field of tank technology application.

<Means/effects for solving the problems> In order to solve the above-mentioned problems, the structure of the present invention, which is based on the above-mentioned claims in accordance with the above-mentioned object, has been designed to solve the above-mentioned problems, but it has been found that there is a risk of fire spreading to the floating roof tank. In this case, the water is discharged from the upper edge of the side wall of the tank, and the cone-shaped upper plate that slopes downward toward the center is placed on the bottom plate of the floating roof. When the outermost aquifer is aquifered, the overflow of the aquifer passes over the overflow weir on the inside of the aquifer and is aquifered to the next inner aquifer. A minimum amount of water is placed in the water gutter and stretched over the floating roof to cool the floating roof board by heat of vaporization, and depending on the design, the outermost water aquifer and the inner surface of the tank side wall may be connected to each other. A fire extinguishing agent such as foam is sprayed in between to seal the evaporated gas from the foam seal of the pontoon and prevent it from catching fire.In case of precipitation, water is collected from the center of the floating roof and drained outside the tank. This is a technical measure that prevents the floating roof from sinking and ensures that the disaster prevention function is fully utilized.

<Embodiment - Configuration> Next, an embodiment of the present invention will be described below based on the drawings.

Reference numeral 1 designates a floating roof tank for oil storage, and on the upper edge 3 of its side wall 2, there are sprinkler pipes 5, 5, which communicate with a water supply pipe 4 connected to a water supply source (not shown), which is smaller than the number of conventional spray heads. The nozzles 6, 6, . . . are provided facing inward.

Further, on the upper edge 3, extinguishing agent injection nozzles 8, 8, .
and the first overflow weir.

9 is a floating roof, and a form seal 12 forming a pontoon as a well-known sealing mechanism is attached to the inner surface of the tank side wall 2 of the side wall flange 11 of the bottom plate 10.
Corncave-shaped upper plate 14 sloping downward toward 3
Concentric float chambers 16, 16 are formed by interposing a ring-shaped partition wall concentrically between the bottom plate 10 and the bottom plate 10.
...is formed.

Ring-shaped overflow weirs 17, 17, . A drainage pipe 20 is provided on the side wall 2 via a flexible hose 19 that serves as a water collection channel.
It is connected to the.

Therefore, concentric aquifers 21, 21 are formed between each overflow weir 17, 17..., and the floating roof 9
A minimal weight aquifer can be placed on top.

Incidentally, since the aquifer groove 21 is ring-shaped, in extreme cases, only one nozzle 6 is sufficient.

Although the outermost overflow weir 17 does not exactly have an overflow function, it forms a retention zone 23 for the fire extinguishing foam 22 between it and the inner surface of the side wall 2.

In addition, 24 is aquifer and 25 is stored petroleum.

<Embodiment - Effect> In the above-described configuration, the floating roof tank 1 is operated by raising and lowering the floating roof 9 as shown by arrow A depending on the receiving and discharging state of the stored oil 25.

If a fire breaks out in an adjacent tank (not shown), fire extinguishing water is immediately supplied to the water supply pipe 4 via an operation mechanism (not shown), and a fire extinguishing agent is also supplied from the supply pipe 7.

Therefore, water is sprayed from the nozzles 6, 6, . . . to the outermost aquifer 21.

Then, the water that fills the outermost aquifer 21 overflows the weir 17 and starts to aquifer the next inner aquifer 21, and then sequentially in each inner aquifer 21.
The water that fills the innermost water aquifer 21 overflows from the overflow pipe 18 and is discharged to the outside of the system through the drainage channel of the hose 19 and the drain pipe 20.

Therefore, the amount of water supplied to the water supply pipe 4 can be adjusted as appropriate by checking the state of drainage from the drainage pipe 20.

The aquifer on the floating roof 9 flows through a cone-cave-shaped upper plate 14 and a weir 17 into a stepped aquifer 2.
1, 21, . . . , the amount is the minimum required amount even in a full water state, and an excessive aquifer load is not applied to the floating roof 9.

Also, regarding the timing when the water aquifer becomes full on the floating roof 9, the upper plate 14 and the weir 17,
By setting the size of 17..., the process can be completed early.

In this way, the water aquifer 24 is spread uniformly over the entire surface of the floating roof 9, and the heat of vaporization cools the floating roof 9, insulating it from heat, and prevents the oil level on the lower surface of the floating roof 9 from evaporating.

In this case, in a state where precipitation has been deposited in advance, water supply by water supply is quickly completed.

On the other hand, at the same time as the aquifer 24 is stretched, the extinguishing agent from the feed pipe 7 is injected downward from the injection nozzles 8, 8..., and the ring between the outermost overflow weir 17 and the inner surface of the side wall 2 is The retention zone 23 is filled with foam fire extinguishing agent 22 in multiple layers to prevent ignition of the foam seal 12 and leakage of petroleum vapor from the foam seal 12.

During this time, since the retention zone 23 between the inner surface of the side wall 2 and the outermost overflow weir 17 is ring-shaped, the water is reliably stored without overflowing to the inside, and the sealing function is effectively exerted.

In this way, the heat and disaster prevention treatment for the floating roof 9 and the seal portion for the inner side 2 is smoothly performed.

During the disaster prevention process, as mentioned earlier, the weight of the water on the floating roof 9 does not become that large even when it is full, so the floating roof 9 does not sink into the stored liquid, and therefore, in the event of a serious situation such as a fire in the entire tank, Not enough.

In the summer, the temperature rise due to sunlight on the floating roof 9 is extremely high, and therefore, in this case, the steam generation on the oil surface on the lower surface of the floating roof 9 is likely to cause ignition and ignition.

To deal with this, it is also possible to constantly cool and heat-insulate the building by making the rain water aquifer, or by periodically replenishing the water aquifer.

Therefore, it goes without saying that the embodiments of the present invention are not limited to the above-mentioned embodiments, and that various other embodiments can be adopted, and in terms of design changes, the water spray device is not limited to the nozzle. It may be made to directly face the outermost aquifer via a flexible hose.

Further, the depth, slope, etc. of each aquifer may be made different from each other, and there are various degrees of freedom in design.

If it is undesirable to constantly collect water due to rainfall, it is also possible to design the weir so that rainwater drain holes are provided in the weir.

Depending on the design, sealing with fire extinguishing foam may not be performed.

<Effects of the Invention> As described above, according to the present invention, in the thermal insulation structure of a floating roof tank in which a water discharge device is placed on the upper edge of the tank side wall facing the floating roof, a cone cave that slopes downward at the center provided on the bottom plate of the floating roof is provided. By arranging multiple aquifer grooves concentrically on the upper surface of the top plate of the shape, descending down to the center via an overflow weir, basically overflow can be prevented by simply discharging water into the outermost aquifer grooves. Water can be aquifered to the lower aquifer through the flow weir, and therefore the entire surface of the floating roof can be aquifered using an extremely small waterway, and at a lower pressure than before. It requires fewer pumps, has simple facilities, is easy to maintain, and has the excellent effect of being able to cool and heat aquifer water with less power and water consumption.

In that case, by specifying the slope of the upper surface of the floating roof plate, the height of the weir, etc., the depth of the aquifer can be designed to be as small as possible, and the entire surface is aquifer. Not only can the appearance of the water be carried out quickly, but the amount of aquifer water can be kept to the necessary minimum, and therefore the weight of the floating roof can be reduced, and the floating roof can be cooled without being submerged in the liquid. Can fully demonstrate its functions,
It also has the effect of making disaster prevention possible.

Furthermore, by installing a water collection device in the center of the floating roof and discharging water outside the tank, not only is there no risk of excess water due to excess water discharge, but the amount of water supplied can be adjusted based on the amount of overflow water. There are some benefits to doing so.

Furthermore, in addition to cooling by forced water supply, natural water aquifers due to precipitation can be used throughout the area, and as long as this is possible, natural disaster prevention and heat protection can be achieved at all times, floating roof heating in summer can be achieved, and emergency It also has the advantage of requiring less hydrophobicity.

[Brief explanation of the drawing]

The drawings are explanatory diagrams of one embodiment of the present invention, with FIG. 1 being a schematic cross-sectional view of the whole, and FIG. 2 being an enlarged perspective view of the same portion. 1...Floating roof tank, 2...Side wall, 3...Top edge, 9...Floating roof, 13...Center, 18...Water collection device, 19, 20...Drainage channel, 14...Top surface, 2
1...Aquifer, 17...Overflow weir.

Claims (1)

[Claims] 1 In a heat-insulating structure in which a water discharge device is provided at the upper edge of the tank side wall of a floating roof tank to face the floating roof, and a water collection device provided at the center of the floating roof is connected to a drainage channel connected to the tank side wall. , a plurality of ring-shaped aquifers descending toward the center are concentrically provided on the upper surface of the downwardly sloping concave-shaped upper plate provided on the bottom plate of the floating roof, and adjacent aquifers overflow. Thermal insulation structure of a floating roof tank characterized by being partitioned by a weir.