JPS5911916Y2 - Gas main seal unit device in inert gas explosion-proof system - Google Patents

Description

[Detailed description of the invention] The present invention is used in an inert gas explosion-proof system in which inert gas such as carbon dioxide gas or nitrogen gas is supplied and filled into the gas phase of a cargo oil tank or the like for the purpose of explosion-proofing the tank. A gas main seal unit device that can prevent unexpected situations from occurring due to gas backflow in the gas main pipe that communicates the air supply source and the explosion-proof part due to an abnormality occurring inside the tank, especially explosion-proofing the cargo oil tanks of oil tankers. The present invention relates to a gas main pipe seal unit device in an inert gas explosion-proof system.

When explosion-proofing the cargo oil tank of an oil tanker, the inert gas filled into the gas phase of the cargo oil tank desulfurizes and de-sulfurizes the combustion gas from the boiler installed in the engine room of the oil tanker.
It is advantageous to use it after removing dust and cooling it.

This invention was made especially from this perspective,
Examples thereof will be described below based on the drawings.

1 is a boiler (not shown), which is an example of an air supply source installed in the engine room of an oil tanker.

), this flue is connected to a cargo oil tank 2, which is an example of an explosion-proof part, through a gas main pipe 3, and the inert gas in the flue 1 is fed into the cargo oil tank 2 to drain the tank. 2 is explosion-proof.

The main gas pipe 3 consists of an upstream gas main pipe 3A and a downstream gas main pipe 3B, which are connected to each other via a seal unit device 4.

As is clear from FIG. 2, the seal unit device 4 is
A small-capacity water storage tank 6 is located on the upper side of the sealed casing 5.
A water seal tank 7 having a diameter smaller than that of the casing 5 is provided at the bottom.

A water supply port 8, an overflow roller 9, and an air belt 10 are provided at the upper part of the water storage tank 6, and a water supply pipe 12 with a seawater pump 11 interposed therein is connected to the water supply port 8.

On the other hand, the water seal tank 7 has a heating steam pipe 13 disposed therein, and has an upper half of its side wall as a dam 14 projecting into the casing 5, and a lower half projecting outside the casing 5. ing.

The water seal tank 7 is connected to the water storage tank 6 by a downcomer pipe 15A having an on-off valve 15 in the lower half of its side wall.
It is connected to the bottom.

The downcomer pipe 15A is arranged with its entire length outside the casing 7
By not penetrating the outer wall of the casing 5, there is no need to use special materials for the piping.
Economical.

The casing 5 has an inert gas outlet 16 in its upper wall and a drain 17 in its bottom wall.

Further, a demister 18 is provided between the inert gas outlet 16 and the water seal tank 7 inside the tank.

A gas inlet pipe 19 is arranged at the axial center of the casing 5, and its tip is inserted into the water seal tank 7.

And the end of the upstream gas main pipe 3A is connected to its upper end.

Interposed in the middle of the upstream gas main pipe 3A are a scrubber 20, a demister device 21, and two air supply fans 22A and 22B arranged in parallel with each other in order from the upper side.

A cooling seawater injection pipe 25 having a pump 23, a flow meter 24, etc. is connected to the scrubber 20.

Also, between the flue 1 and the scrubber 20 and the air supply fan 2
On-off valves 26 . 27 intervening.

As mentioned above, two air supply fans 22A and 22B are installed in parallel with each other, and these are connected to inlet vanes 28A and 28B and outlet vanes 29A and 29B, respectively.
and a wash water supply pipe 3 passing through the internal flow path.
It has 0A and 30B.

Outlet vane 29A of air supply fans 22A, 22B
, 29B outlet is connected to the lower part of the scrubber 20 by a return pipe 31 branched from the upstream gas main pipe 3A, and an on-off valve 32 is interposed in this return pipe 31.

A pressure transmitter 33 is installed in the downstream gas main pipe 3B, and the internal pressure of the cargo oil tank 2 is detected by this pressure transmitter, and this can be converted into an electric signal for predetermined control.

The downstream gas main pipe 3B communicates with the cargo oil tank 2 via branch pipes 34A and 34B.

In addition, 35 is an oxygen meter, 36 is a play force, 37 is a vent post, 38 is a fresh air introduction pipe, 39A, 39B are on-off valves provided in the branch pipes 34A, 34B, and among these, the fresh air introduction pipe 38 Air can be taken in from above the oil tank deck 40.

In the above, the seawater pump 11 is constantly operated to continuously supply water to the water storage tank 6.

Prior to filling the cargo oil tank 2 with inert gas, the scrubber 20 and the air supply fans 22A and 22B are stopped, the on-off valves 26 and 27 are closed, and only the on-off valve 15 is opened, and the water storage tank 6 is passed through the downcomer pipe 15A. Water seal tank 7
Supply water inside.

Since the water seal tank 7 has a smaller diameter than the casing 5, when the on-off valve 15 is opened, water immediately fills inside and overflows from the weir 14.

The overflow water is discharged from the drain port 17, merges with the overflow water from the water storage tank 6, and is dumped overboard.

In this state, the tip of the gas manifold pipe 19 is immersed in the seal water in the water seal tank 7.

Next, filling of the cargo oil tank 2 with inert gas is started.

That is, while starting the scrubber 20, the on-off valve 2
6 is opened and the inert gas in the flue 1 is removed from the scrubber 20.
and perform operations such as cooling, dust removal, and desulfurization.

Then, the air supply fans 22A and 22B are operated, and at the same time, the on-off valve 15 in the downcomer pipe 15A is closed, water supply to the water seal tank 7 is stopped, and seal water is stored in the water seal tank 7. .

Next, when the on-off valve 27 is opened, the inert gas is sent into the seal unit device 4 by the air supply fans 22A and 22B, and is ejected from the tip of the gas inlet pipe 19 due to its discharge pressure.

Therefore, the seal water in the water seal tank 7 is blown outward from the tank 7 and discharged from the drain port 17 to the outside of the boat.

As a result, the water seal at the tip of the gas inlet pipe 19 is broken, and the inert gas passes through the demister 18 to remove entrained water, and then passes through the inert gas outlet 16, the downstream gas main pipe 3B, and the branch pipes 34A, 34B. The cargo oil is filled into the cargo oil tank 2 through the

The tip of the gas inlet pipe 19 is resealed as follows.

First, by stopping the air supply fans 22A and 22B, the on-off valves 26 and 27 are closed, and at the same time, the on-off valve 15 is opened.

As a result, water is instantly supplied from the water storage tank 6 into the water seal tank 7 through the downcomer pipe 15A.

This performs resealing. In addition, the difference in wood head when supplying water from the water storage tank 6 to the water seal tank 7 is based on the casing 5.
Since the pressure is higher than the inert gas pressure in the tank, water can be supplied to the water seal tank 7 quickly and reliably.

In addition, on-off valves 15, 26, 27, 32, air supply fan 22A
, 22B, and the scrubber 20 are connected to each other or are limited to necessary ones through detection of the internal pressure of the cargo oil tank 2 by the pressure transmitter 33, etc.

As is clear from the above explanation, according to the present invention, it is possible to supply inert gas in a dry type, which is not only advantageous in terms of corrosion prevention, but also enables quick and reliable water sealing in the middle of the gas main pipe in an explosion-proof system. In addition, since the seal release operation is also used as the inert gas supply start operation, control is easy.

Furthermore, since the water seal tank is configured to have a smaller diameter than the casing, the amount of water required for water sealing is reduced, and therefore, water sealing and water seal release operations can be performed more quickly. Furthermore, in the case of an explosion-proof system for a ship, the amount of movement of the water surface in the water seal tank due to the movement of the ship body is reduced, and a reliable water seal effect is exhibited.

Furthermore, since the entire length of the downcomer pipe that connects the water storage tank and the water seal tank is provided outside the casing, there is no need for piping made of special materials, which is advantageous in terms of economy and workability.

[Brief explanation of the drawing]

FIG. 1 is a flow diagram of an inert gas explosion-proof system using an apparatus according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of the apparatus according to the embodiment. 1... Flue, 2... Oil tank, 3.
...Gas main pipe, 3A...Upstream gas main pipe,
3B...downstream gas main pipe, 4...seal unit device, 5...closed type kennising, 6...
...Water storage tank, 7...Water seal tank, 8
...Water inlet, 9...Overflow,
11...Seawater pump, 12...
Water supply pipe, 14... Weir section, 15... Opening/closing valve, 15A... Downpipe, 16... Inert gas outlet, 17... Drain port, 18...
...Demister, 19... Gas inlet pipe.

Claims (1)

[Scope of utility model registration request] A water storage tank is provided in the upper part of a closed type casing having an inert gas outlet, and a water seal tank with a diameter smaller than that of the casing is provided in the lower part, a water supply port and an overflow are provided in the water storage tank, and this water storage tank and the water seal tank are provided The bottoms of the water-sealed tank are connected to each other on the outside of the casing by a downcomer pipe having an on-off valve, and the upper end of the side wall of the water-sealed tank is used as a dam, and inside this water-sealed tank, there is a gas inlet that communicates with the air supply fan outlet. A gas main pipe sealing unit device in an inert gas explosion-proof system, wherein a pipe tip is inserted, the casing has a drain port at its bottom, and a demister between the inert gas outlet and a water seal tank.