JP2001199389A - Cleaning system in ballast tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently remove precipitated mud in a ballast tank. SOLUTION: Pressurized washing water is supplied from a fire-fighting water pipe 2 to the ballast tank 1 through a connection hose 3 and a washing water supplying pipe 4. A nozzle 6 is attached near the bottom 5 of the ballast tank, and the washing water is injected from it. The precipitated mud and the washing water pushed to one side in the ballast tank 1 by the injection of the washing water is sucked through a suction port 10 by an elector 8 connected to a large capacity pump 9, and discharged out of a ship through the ship bottom 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a petroleum tanker,
The present invention relates to a ballast tank cleaning system for washing mud settled in ballast tanks of all ships such as LNG ships, bulk carriers, and PCC ships.

[0002]

2. Description of the Related Art Ships that carry cargo are equipped with ballast tanks in their hulls and inject seawater into them to obtain navigation stability in an empty hold state. The seawater injected into the ballast tank is injected at the port where the ship departs, is maintained in the tank during navigation, and is discharged when loading cargo at the partner port. In addition, the seawater is generally injected into the ballast tank at the port where the ship departs. On this occasion,
The seawater at the port will be pumped up, but since the water depth of the port is relatively shallow, it will pump up mud near the seabed and inject it into the ballast tank. The mud injected in this manner settles at the bottom of the tank during navigation, and remains in the tank simply by discharging the ballast water at the partner port.

In recent years, in view of the fact that seawater transportation accompanying the above-mentioned ballast navigation has a high possibility of causing environmental pollution or ecosystem collapse at the partner port, legislation for regulating this has been advanced internationally. , Cleaning in the ballast tank can no longer be ignored. For this reason, recently, when a ship docks, it is customary to manually clean the ballast tank.
Specifically, only a ballast tank with a wide frontage and a simple shape is used for cleaning by inserting a cleaning machine from the upper deck, while a ballast tank with a narrow frontage or a complicated shape is visually inspected by seafarers. While cleaning the ballast tank manually.

[0004]

However, in the above-mentioned prior art, since cleaning is basically performed manually, it is troublesome, and in a ballast tank having a complicated shape in which the bottom of the tank cannot be seen, the removal of mud is substantially impossible. There was a problem that it was difficult. Such residual mud leads to an increase in the weight of the hull, resulting in a decrease in loadable cargo.

[0005] In addition, if legislation such as a treaty that ballast water pumped at a port at the time of departure cannot be drained as it is at the partner port is established, it is necessary to replace ballast water with clean seawater once in the ocean during navigation. However, even in such a case, simply replacing the ballast water does not eliminate mud settled at the tank bottom. Even more, it is virtually impossible to manually clean a plurality of ballast tanks while sailing.

The present invention has been made in view of the above, and provides a ballast tank cleaning system which is provided in advance in each ballast tank at the time of shipbuilding, and which efficiently removes sediment in the ballast tank without human power. The purpose is to provide.

[0007]

In order to achieve the above object, a ballast tank cleaning system according to claim 1 includes a water source for supplying pressurized cleaning water and a water source in a ballast tank of a hull. A washing water supply pipe that guides washing water from the tank, an eductor with a suction port located near the bottom of the ballast tank, a suction pump connected to the eductor, and a discharge port that discharges muddy water sucked by the suction pump to the outside of the ship. It is provided with.

[0008] The pressurized cleaning water from the water source is guided into the ballast tank through the cleaning water supply pipe, and is injected into the ballast tank from the tip of the cleaning water supply pipe. The mud accumulated at the bottom of the ballast tank by this injection is pushed out to the side opposite to the cleaning water supply pipe. Then, the extruded mixture of the washing water and the mud is sucked by an eductor connected to the suction pump, and is discharged from the discharge port to the outside of the boat.
The water source may be, for example, a combination of a tank and a compressor.

In the ballast tank cleaning system according to the present invention, the water source is a fire extinguishing main pipe, and pressurized cleaning water is supplied from the fire extinguishing main pipe to the cleaning water supply pipe by a communication hose. Is to lead to. Ships of a certain size or more are always equipped with fire extinguishing water pipes for fire prevention. Therefore, if this fire extinguishing water pipe is used as the water source, and is connected to the washing water supply pipe with a connecting hose therefrom, seawater can be easily guided to the ballast tank.

According to a third aspect of the present invention, in the ballast tank cleaning system, the cleaning water supply pipe has a nozzle in the ballast tank, and the nozzle has a divergent shape. . Since the nozzle has a divergent shape, pressurized cleaning water can be supplied to a wide area of the ballast tank, and a wide range of mud can be pushed to the eductor side.

In the ballast tank cleaning system according to a fourth aspect of the present invention, in the ballast tank cleaning system, the ballast tank cleaning system is further attached to the cleaning water supply pipe so as to be rotatable within a certain range, and is provided in the cleaning water supply pipe. The apparatus includes a nozzle having a protruding flow conduit that is resistant to the flow of cleaning water in a portion to be buried, and switching means for switching a direction of the cleaning water flowing through the cleaning water supply pipe.

The cleaning water supply pipe in the ballast tank has a nozzle, and the nozzle is rotatably mounted within a certain range. And since the part buried in the washing water supply pipe has a protruding flow conduit that is resistant to the flow of the washing water, the nozzle is left or right depending on the flow direction of the washing water flowing in the washing water supply pipe. Will shake his head. By this action and the switching means for switching the direction of the washing water flowing through the washing water supply pipe in the ballast tank, the washing water can be jetted while simultaneously aligning the directions of the nozzles in the ballast tank. In addition, by changing the flow direction of the washing water, it is possible to widely remove mud settling in the ballast tank.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a ballast tank cleaning system according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited by the embodiment.

(Embodiment 1) FIG. 1 is a sectional view showing a ballast tank cleaning system according to Embodiment 1 of the present invention. FIG. 1 (a) is an L-shaped ballast tank often seen in large ships. Cross-section view from the side,
(B) is a cross-sectional view as seen from above. In FIG. 2B, some components shown in FIG. 2A are omitted. Cleaning water is supplied to the ballast tank 1 from a fire extinguishing water pipe 2 via a communication hose 3 and a cleaning water supply pipe 4.
A nozzle 6 for injecting the washing water is provided near the bottom 5 of the ballast tank 1, and the supply and shutoff of the washing water is provided between the fire extinguishing water pipe 2 and the washing water supply pipe 4. This is performed by the valve 7. It is preferable that the shape of the nozzle 6 be widened toward the outlet in order to spray the cleaning water as widely as possible. In addition, spraying may be performed over a wide range by attaching a sprinkler.

An eductor 8 is disposed near the bottom 5 of the ballast tank 1 and at the end opposite to the nozzle 6. The pipe from the eductor 8 is connected to a large capacity pump 9, and the pipe from the large capacity pump 9 is connected to the ship side 11.

Next, the operation of the ballast tank cleaning system will be described. A fire extinguishing water pipe 2 as fire protection equipment is provided in a wide area of the hull of a large ship having a certain size or more such as a tanker. Generally, the fire water pipe 2 is filled with seawater pressurized so that seawater can be sprayed when a fire occurs. The in-ballast tank cleaning system uses pressurized seawater from the fire extinguishing water pipe 2 as a water source. That is, when cleaning is required, the valve 7 is opened to guide the cleaning water as pressurized seawater in the fire-extinguishing water pipe 2 into the ballast tank 1 through the communication hose 3 and the cleaning water supply pipe 4. At the bottom 5 of the ballast tank 1, the washing water is injected from the nozzle 6, and the settled mud is pushed out in the opposite direction to the nozzle 6.

The sediment mud and the washing water which have been pushed to one side by the injection of the washing water are sucked by the eductor 8 connected to the large capacity pump 9 and discharged out of the ship from the side 11 of the ship (FIG. 1 (a)). , Indicated by arrows). Further, if the jetting of the washing water and the suction from the eductor 8 are performed at the same time, a constant flow is generated in the ballast tank 1, and the mixture can efficiently suck and discharge the mixture of the washing water and the mud.

FIG. 2 is a sectional view showing a modified example in which the arrangement of the washing water supply pipe shown in FIG.
(A) is a sectional view of the ballast tank viewed from the side, (b)
Is a cross-sectional view of the same as viewed from above. Thus, by arranging the washing water supply pipes 4 and 21 vertically and horizontally in the ballast tank 1 and connecting the plurality of nozzles 6 to the washing water supply pipes 4 and 21, the water flow vector generated by the jetted washing water is obtained. Becomes as indicated by the arrow 22, and the suction efficiency of the eductor 8 can be improved.

In the cleaning system in the ballast tank shown in FIGS. 1 and 2, the cleaning water supply pipes 4 and 21 are arranged along the outer side surface and the bottom portion 5 of the ballast tank 1; It may be arranged along the upper surface of the tank. In this case, the cleaning water is sprayed with the nozzle 6 directed slightly downward to promote the mud stirring action.

As described above, according to the cleaning system in the ballast tank, the cleaning water supply pipes 4 and 21 in the ballast tank 1 and the eductor 8 are combined.
Sediment can be removed efficiently. In addition, if the opening and closing of the valve 7 is automated by an electromagnetic valve or the like, the sediment in the ballast tank 1 can be automatically cleaned with one button,
Cleaning can be easily performed not only when the ship enters the dock but also at sea. As a result, it is possible to clear the water quality standards for ballast drainage in ports that will be regulated in the future.

(Embodiment 2) FIG. 3 is a sectional view around a nozzle of a cleaning system in a ballast tank according to Embodiment 2 of the present invention. This in-ballast tank cleaning system is characterized in that the nozzle 31 has a rotating structure. The other configuration is the same as that of the first embodiment, and the description thereof is omitted. The nozzle 31 has a spherical body 32 at its body portion, and this portion is connected to the washing water supply pipe 3.
3 and the mounting cover 34. This is a structure for rotating the nozzle 31 within a certain range, and is not limited to the one using the spherical body 32 in particular, but may be one using a cylindrical shape or the like. The washing water supply pipe 33
The washing water supply pipe 33 and the mounting cover 34 are provided with appropriate seals (not shown) in order to prevent the washing water, which is pressurized seawater, from leaking.

The nozzle 31 is provided with a washing water supply pipe 33.
A flow conduit 35 protruding from the spherical body 32 is provided in a portion buried in the space, that is, a portion exposed to the washing water flow, and an opening thereof is opened in both the left and right directions. The flow conduit 35 has a resistance to the flow of the cleaning water in the cleaning water supply pipe 31, and is inclined in the downstream direction around the center of the spherical body 32 as a fulcrum. Therefore, the nozzle 31 is inclined in the upstream direction of the washing water, opposite to the flow conduit 35.

FIG. 4 is a configuration diagram showing an entire ballast tank cleaning system according to a second embodiment of the present invention. The ballast tank 1 is provided with cleaning water supply pipes 41 and 42 and nozzles 43 and 44 in both vertical and horizontal directions. The cleaning system in the ballast tank includes the cleaning water supply pipes 41 and 42 in the ballast tank 1.
Means for switching the direction of the washing water flowing through the washing machine. That is, the two cleaning water supply pipes 41 and 42 are provided with a pipe 4 for supplying cleaning water from a water source such as a fire-extinguishing water pipe to each end.
5 to 48 are connected together with the valves 49 to 53, and by operating these valves 49 to 53, the directions of the washing water flowing to the washing water supply pipes 41 and 42 arranged vertically and horizontally are independently controlled. I am trying to do it.

For example, when the valves 49, 50 and 52 are opened and the valves 51 and 53 are closed, the nozzles 43 and 44 are inclined in the directions shown in FIG. As a result, a counterclockwise flow of the washing water as shown by an arrow 54 is generated, and the mud entrained therein is sucked by the suction port 10 of the eductor located at the center of the ballast tank 1. The reason why the flow of the washing water is formed counterclockwise is to utilize the fact that Coriolis acceleration occurs counterclockwise in the Northern Hemisphere. Therefore,
In the southern hemisphere, the flow of cleaning water may be formed clockwise. In this case, the valves 49, 51, and 53 may be opened and the valves 50 and 52 may be closed to generate a clockwise flow of the washing water.

As described above, according to the cleaning system in the ballast tank, in addition to the effect of the first embodiment, the flowing direction of the cleaning water in the cleaning water supply pipes 41 and 42 is changed by operating the valve. , 44
Can be inclined, so that a swirling flow can be created in the ballast tank 1, and as a result, the sediment can easily be entrained and the sediment can be removed efficiently. By operating the valves 49 to 53, the cleaning water supply pipe 4 is operated.
If the flow direction of the washing water is changed alternately in 1, 42, the stirring action of the washing water and the settling mud can be induced, and a wide range of mud can be eliminated.

[0026]

As described above, according to the ballast tank cleaning system of the present invention (claim 1), the equipment necessary for cleaning the ballast tank is provided in advance in the ballast tank as fixed equipment for the ship. There is no need to work manually. Also,
Even when the ballast tank has a complicated three-dimensional structure, such as one utilizing a double bottom gap of a ship, mud at the tank bottom can be efficiently drained. Thus, the ballast tank can be easily and efficiently cleaned not only when the ship enters the dock but also when performing ballast water replacement work on the sea.

Further, if cleaning becomes possible easily during the voyage, the seawater in the ballast tank can be kept clean, so that future legislation that requires a high quality standard of ballast water discharged from ships at the loading port is also required. It is possible to respond. Further, since the present invention has a relatively simple configuration, the in-ballast tank cleaning system can be realized at low cost.

According to the ballast tank cleaning system according to the present invention (claim 2), the existing fire extinguishing water pipe is used as a water source, and the connecting fire hose is connected to the cleaning water supply pipe. It is not necessary to provide the seawater, and the seawater serving as the washing water can be easily guided to the ballast tank. Further, according to the cleaning system in the ballast tank according to the present invention (claim 3), the nozzle is formed to have a divergent shape, so that the efficiency of removing settled mud can be improved.

Further, according to the ballast tank cleaning system according to the present invention (claim 4), the spray direction of the nozzle attached to the cleaning water supply pipe can be taken in a wide range, and the mud settling in the tank can be reduced. More can be eliminated. In addition, since it has a relatively simple configuration, a cleaning system in a ballast tank can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a ballast tank cleaning system according to a first embodiment of the present invention;

FIG. 2 is a cross-sectional view showing a modification in which the arrangement of the cleaning water supply pipe shown in FIG.

FIG. 3 is a sectional view showing the vicinity of a nozzle of a ballast tank cleaning system according to a second embodiment of the present invention;

FIG. 4 is a configuration diagram showing an entire ballast tank cleaning system according to a second embodiment of the present invention;

[Description of Signs] 1 Ballast tank 2 Fire extinguishing water pipe 3 Communication hose 4, 21, 33, 41, 42 Cleaning water supply pipe 5 Bottom part 6, 31, 43, 44 Nozzle 7, 49-53 valve 8 Eductor 9 Pump 10 Suction port 32 Spherical body 35 Flow conduit 45-48 Piping

Claims (4)

[Claims] 1. A water source for supplying pressurized cleaning water, a cleaning water supply pipe for guiding cleaning water from the water source into a ballast tank of a hull, and an eductor having a suction port near a bottom of the ballast tank. A suction pump connected to the eductor; and a discharge port for discharging muddy water sucked by the suction pump to the outside of the ship. 2. The cleaning system in a ballast tank according to claim 1, wherein the water source is a fire extinguishing main pipe, and pressurized cleaning water is led from the main fire extinguishing pipe to a cleaning water supply pipe by a communication hose. 3. The cleaning system according to claim 1, wherein the cleaning water supply pipe has a nozzle in the ballast tank, and the nozzle has a divergent shape. 4. A cleaning device according to claim 1, wherein said cleaning water supply pipe is provided with a protruding flow conduit which is rotatably mounted within a predetermined range and which is buried in said cleaning water supply pipe. The cleaning system in a ballast tank according to any one of claims 1 to 3, further comprising: a nozzle having the nozzle; and switching means for switching a direction of the washing water flowing through the washing water supply pipe.