JPS6117035Y2 - - Google Patents

Description

[Detailed description of the invention] This application relates to a ventilation system for a floating roof tank with a fixed roof, which takes outside air into the tank for effective ventilation and prevents air from entering the tank when outside air is taken out. The purpose of this is to separate and remove the water that comes from the tank and prevent it from entering the stored liquid.

Generally, when storing highly volatile substances, tanks are used that are equipped with floating roofs that move up and down to follow the rise and fall of the liquid in order to suppress evaporation of the liquid from the standpoint of pollution prevention and safety. Among these tanks, tanks that are constructed in places with particularly severe external conditions such as weather conditions, and tanks that store substances that are extremely sensitive to moisture intrusion, are equipped with a fixed roof to block out external influences. Floating roof tanks are often used.

In such a floating roof tank with a fixed roof, a large amount of flammable paper that was present on the underside of the floating roof is released onto the floating roof when liquid is being received, creating an extremely dangerous situation. Vent holes are usually provided in the upper side panels or fixed roof edges to introduce air and dilute the concentration of combustible paper accumulated on the floating roof below a dangerous level.

Furthermore, as mentioned above, these types of tanks often store substances that are extremely sensitive to water or other contamination, so it is essential to take measures to prevent rainwater from entering through the vents. .

Several measures have been proposed in the past to prevent rainwater from entering, but all of them involve blocking rainwater from outside the tank. This has the disadvantage that the presence of this material significantly obstructs the inflow of air into the tank.

For example, as shown in FIGS. 6 and 7, a vent C is bored near the top of the side wall B of the storage tank A, and a cover D covering the top and sides is attached to the outside of the vent C. Alternatively, since the lower opening of the cover D is provided with a shielding plate E made of a breathable mesh or punched metal, the presence of the cover D significantly obstructs the inflow of air into the tank.

The present invention was devised in view of the above-mentioned circumstances.The outside air is effectively introduced into the tank using the air intake guide, and after colliding with a drain plate or wire mesh to separate and remove moisture, the air is removed from the guide plate. By guiding the air downward, it mixes with and dilutes the flammable paper accumulated on the floating roof, quickly reducing the paper concentration to below the dangerous concentration, making the inside of the tank safe, and also draining rainwater into the storage liquid. To provide a ventilation system for a floating roof type tank with a fixed roof, which prevents the intrusion of such substances.

Now, in order to achieve the above-mentioned purpose, one embodiment will be described.In the vicinity of the connecting part between the fixed roof 3 and the side wall 4 of a storage tank 2 with a fixed roof, in which a floating roof 1 is installed vertically movably, A vent hole 5 is bored in the fixed roof 3 or the side wall 4, and an air intake guide tube 6 with a large diameter outer end opening is provided outside the vent hole 5. A rainwater tray 7 having a raised edge plate 7a around the circumference wider than the ventilation hole 5 is fixed to the side wall 4 at a position close to the ventilation hole 5,
The rainwater tray 7 is located at the upper part of the rainwater tray 7 and is located closer to the side wall 4 than the rising edge plate 7a inside the rainwater tray 7.
A draining member 8 whose lower end portion 8a is located close to the bottom plate 7b of the screen is fixed to the inner surface of the fixed roof 3 or the inner surface of the side wall 4, and the width W of the draining member 8 is It should be sufficiently wider than the width W' of the rainwater tray 7, and a drain pipe 9 should be installed at the bottom center of the rainwater tray 7.
This relates to a ventilation system for a floating roof type tank with a fixed roof, in which the upper ends of the drain pipe 9 are connected through an open connection, and the other end of the drain pipe 9 projects outside from the side wall 4.

The draining member 8 is formed so as to cover the upper and side parts with wire mesh, punched metal, or a thin flat plate,
It is formed with an opening 8b only in the lower part.

Furthermore, to describe the shape of the draining member 8 in detail, in the case of FIGS. 2 and 3, the upper end of the draining member 8 is fixed inside the fixed roof 3 above the vent 5, and both ends of the draining member 8 are fixed to the inside of the fixed roof 3. The fixed roofs 3 are connected by an air guide 10 formed of a flat plate to close both sides, and the lower part is opened to form an air retention space 12, and the lower part of the draining member 8 is formed into a wide trapezoid. Therefore, the air guides 10 on both sides are provided so as to widen from the top to the bottom.

In the case of FIGS. 4 and 5, the air guide 11 is made of a flat plate and has a semicircular cross section, and the central horizontal portion 11a of the air guide 11 is positioned above the vent 5 and fixed to the inner surface of the side wall 4. with air guide 1
A draining member 8 is vertically fixed to the inner end surface of the draining member 1, and the upper side and inner surface are surrounded by the air guide 11 and the draining member 8, and an air retention space 12 is formed with the lower part open.

The present application has the air intake guide tube 6 with the above configuration.
Air or a mixture of air and rainwater is introduced into the storage tank 2 through the opening and enters the air retention space 12, and the rainwater collides with the drainage member 8 and falls through the drainage member 8.
Fallen rainwater is collected in a rainwater tray 7 and drained to the outside of the storage tank 2 via a drain pipe 9, and the inflowing air or air from which rainwater has been removed is collected in a draining member 8 and an air guide 1.
0 and 11 are used as air flow guides to forcibly feed the air downward.

As described above, in the storage tank 2 with a fixed roof, in which the floating roof 1 is movably moved up and down, a ventilation hole is provided in the fixed roof 3 or in the side wall 4 in the vicinity of the connection between the fixed roof 3 and the side wall 4. 5, and an air intake guide cylinder 6 having a large diameter outer end opening is provided on the outside of the vent 5, and a vent is provided inside the side wall 4 at a position below the vent 5 and close to the vent 5. A rainwater catcher 7 having a rising edge plate 7a on the periphery wider than 5 is fixed to the side wall 4. A draining member 8 whose lower end 8a is located close to the bottom plate 7b of the drain member 8 whose side and upper portions are closed.
is fixed to the inner surface of the fixed roof or the inner surface of the side wall 4, the width W of the drainage member 8 is made sufficiently wider than the width W' of the rainwater catcher 7, and the upper end of the drain pipe 9 is opened at the lower center of the rainwater catcher 7. Connect the other end of the drain pipe 9 to the side wall 4.
Since it protrudes further outward, it reduces the resistance when introducing the air inside the storage tank, and at the same time forces the air flowing into the storage tank to the bottom of the tank, and furthermore, it prevents rainwater that has entered the storage tank from being removed from the floating roof. This has the effect of being able to discharge the liquid to the outside of the storage tank without causing it to fall onto the top.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the entire storage tank, Figure 2 is an enlarged sectional view of the main parts, Figure 3 is a rear view of the same part, Figure 4 is an enlarged sectional view of the main parts of another example, and Figure 5 is the same. 6 and 7 are cross-sectional views of the conventional structure. 1...Floating roof, 2...Storage tank, 3...Fixed roof,
4...Side wall, 5...Vent, 6...Guide tube, 7
...Rainwater tray, 7a...Rising edge plate, 8...Draining member, 8a...Lower end, W...Width, W'...Width,
9... Drain pipe.

Claims (1)

[Scope of utility model registration request] A ventilation hole 5 is bored in the fixed roof 3 or the side wall 4 in the vicinity of the joint between the fixed roof 3 and the side wall 4 of the storage tank 2 with a fixed roof in which the floating roof 1 is movable up and down. An air intake guide tube 6 having a large diameter outer end opening is provided on the outside of the side wall 4, and is located at a position near the vent 5 at the bottom of the vent 5 inside the side wall 4 and has a circumference wider than the vent 5. A rainwater catcher 7 having a rising edge plate 7a is fixed to the side wall 4, and is located at the upper part of the rainwater catcher 7 on the side wall 4 side than the rising edge plate 7a inside the rainwater catcher 7, and close to the bottom plate 7b of the rainwater catcher 7. The draining member 8 with the side and upper portions closed where the lower end portion 8a is located is fixed to the inner surface of the fixed roof 3 or the inner surface of the side wall 4, and the draining member 8 is fixed to the inner surface of the fixed roof 3 or the inner surface of the side wall 4.
The width W is sufficiently wider than the width W′ of the rainwater tray 7,
This ventilation device for a floating roof type tank with a fixed roof is constructed by connecting the upper end of a drain pipe 9 to the lower center of a rainwater tray 7 through an open connection, and protruding the other end of the drain pipe 9 to the outside from a side wall 4.