WO2018178099A1

WO2018178099A1 - System for discharging a dredged material comprising a floating monobuoy

Info

Publication number: WO2018178099A1
Application number: PCT/EP2018/057817
Authority: WO
Inventors: Juan Jose NOVAS ROSALES; Alberto DOPICO MARTINEZ; Carlos Duran Neira; Miguel DURAN LOPEZ; Aaron MARTINEZ ROMERO; Dario SOSA CABRERA; Luis Alberto SANCHEZ CRESPO; Jose Antonio Vilan Vilan; Pablo Izquierdo Belmonte; Pablo YAÑEZ ALFONSO; Xulio Fernandez Hermida
Original assignee: Nodosa, S.L.; Centro De Investigaciones Submarinas, S.L.; Nodosafer, S.L.; Subsea Mechatronics, S.L.
Priority date: 2017-03-31
Filing date: 2018-03-27
Publication date: 2018-10-04
Also published as: ES2684404B1; ES2684404A1

Abstract

The invention relates to a system for discharging a dredged material from the barge of any vessel, hopper or dredger, that is going to discharge to the bed, minimizing dispersion of pollutants and turbidity, and facilitating the connection with the vessel and the discharge, comprising a floating monobuoy and means for guiding material, where the means for guiding material comprise: a) a first section is a floating hose (1) connected between the vessel and an input flange (11); b) a second section is a redirecting circuit of the material; and c) a third submerged section; where the monobuoy (10) is made of two halves that are coupled by means of a screwed joint (14) and where one of the halves of the monobuoy (10) comprises the second section and monobuoy.

Description

SYSTEM FOR DISCHARGING A DREDGED MATERIAL COMPRISING A

FLOATING MONOBUOY

Field of the invention

The present invention relates to floating devices. More specifically, it relates to buoys for discharging materials in a controlled manner, for example, materials produced by dredging, minimizing the impact thereof and the dispersion of pollutants. Background of the invention

The operations for discharging materials are usually carried out from the surface of the vessels to the sea floor. To prevent the dispersion of materials through the water, techniques for encapsulating the materials are commonly used. However, sometimes this encapsulation technique is not feasible and the material disperses upon contact with the water.

This causes the discharged materials to be suspended in the water, and therefore leads to an increase in turbidity until said materials settle to the floor. The area where the materials are finally deposited is larger, and even the internal currents, thermoclines and haloclines of the water can carry the deposited material to an undesirable area.

Therefore, for the purpose of mitigating the environmental impact of this activity, it would be desirable to be able to concentrate the material, prevent dispersion, and eliminate turbidity throughout the water column in the discharge area.

The closest prior art in the state of the art is the document ES1 135628U, belonging to the same inventor. It discloses a circular buoy with a discharge pipe situated in the center thereof and through the buoy, with which it intends to discharge materials while limiting the turbidity close to the floor, thus reducing the effect of the currents and preventing diffuse pollution. Said device has shortcomings that limit the effectiveness thereof or require the support vessel to satisfy certain standards, which is corrected by means of the constituent elements and the new configuration herein presented.

The document E88202515 discloses a discharge system with fabric that has the drawback of excluding from the operations the vessels that do not enable the hull thereof to be opened and the dredged material to descend inside the geotextile to the sea bed.

Meanwhile, P200930047 discloses a continuous method for discharging dredged materials of the state of the art which does not address the problem of minimizing turbidity in the water column.

The following refers to some terms used throughout the present document.

Block is understood as the concrete, stone or anchor block that is used to secure the floating device to the sea bed or floor.

Dredger is understood as the ship equipped with pumps or machinery needed to take materials from the sea floor to transfer them to another location.

Hopper is understood as a flat craft, with the bow and stern having the same shape, which is used to deposit granular materials into the sea.

Swing margin is understood as the free path of movement of the buoy with respect to the mooring or anchor point to the sea floor.

Mooring system is understood as the chain and block assembly that holds the device to the sea floor.

Description of the invention

The present invention solves the problems existing in the state of the art by means of a floating device or monobuoy to confine the material to be discharged in a pipeline and guide it close to the floor, limiting turbidity to the final meters. It provides improved distribution of the emptying system by means of a hose that facilitates the connection with the boat and prevents interference with the signaling systems; an improved design of the spaces for equipment and of work ergonomics; a hydrodynamic design that reduces the force that it has against the currents and waves, especially in offshore operations; and improvements related to protection against impacts.

The present invention presents a system for discharging the dredged material from the barge of any vessel to the bed by means of the use of a system comprising an integrated floating buoy and means for guiding the material to the sea floor.

The system is moored to one or more blocks allowing for more specific or zonal discharge areas according to the swing margin that is given to the mooring system. Said means for guiding comprise three sections; the first section is a floating hose that connects to one side of the monobuoy; the second section is a metal pipe with an inverted "L" shape that forms an integral part of the monobuoy; and the third section is a non-floating or constrained pipe that is joined to the buoy on the lower end thereof, with a length adapted to the mooring depth at the point at which the monobuoy is installed. The material is discharged into the means for guiding by impulsion and is guided to the floor by the force of gravity. The monobuoy does not have pumping equipment, this action is carried out from the ship.

With this system, the content of the barge is emptied to the sea, preventing the dispersion of the dredged material, enabling the deposit thereof to be concentrated on the sea floor, and thereby reducing the environmental, ecological and biological impact on the surrounding area where said discharge is carried out.

Furthermore, upon adjusting the discharge area to limits provided by the manager of the discharge point, it could be sealed upon completing the discharge, using a suitable material.

Likewise, upon carrying out the discharge task, the monobuoy also signals the discharge point. To do so, it incorporates signals in accordance with the IALA (International Association of Lighthouse Authorities) Maritime Buoyage System regulations, including a blinking yellow light signal. The lamp installed on the monobuoy is stand-alone equipment powered by solar panels.

Brief description of the drawings

In order to make the invention more readily understandable, by way of illustration and not limitation, an embodiment of the invention that refers to a series of figures is described below.

Figure 1 shows a schematic view of the invention upon depositing material onto the sea floor.

Figure 2a shows an upper detailed view in the direction A of Figure 1 . Figure 2b shows a view: Detailed side view corresponding to the area B of Figure 1 .

Figure 3 shows a perspective view of the preferred embodiment of the present invention.

Figure 4 shows a side view of the monobuoy of Figure 3.

Figure 5 shows a plan view of the monobuoy of Figure 3. Detailed description of the invention

The discharge monobuoy (10) is part of a floating system that is installed in the area intended for discharging the materials and which allows the dredged materials to be emptied in an ecological manner. Its overall purpose is to manage the dredged material transported in a craft, hopper or any dredger that is currently operational to the vicinity of the bed, minimizing the dispersion of pollutants and turbidity in the area. To do so, it must have the characteristics described below.

It has a system for fastening to the floor or a mooring system (3) that, as shown in Figure 1 , fastens the monobuoy to one or two blocks (4), such that the position thereof is maintained in the area intended for discharging (20), which can be specific or zonal according to the swing margin that is given to the mooring system (3).

Figure 2b shows the eye bolts (12) arranged to secure the chains of the mooring system (3). Preferably, each chain has a first, lighter part and a second, heavier part located near the floor. Optionally, since mooring of the monobuoy is always temporary, a well-shaped anchor could be an alternative to mooring with a block, such as, for example, in situations of discharges with little volume.

The upper part of the monobuoy has fastening points or bitts (17) for crafts, hoppers or dredgers that transport the dredged material. Suitable fastening will allow a swing margin to be obtained where the buoy and ship assembly can move together with the currents and winds throughout the entire discharge process.

The means for guiding the discharge material to the sea floor, which enable continuous discharge by the force of gravity, are included as an integral part of the invention. Said means for guiding are presented as a pipeline composed of three sections joined together, where:

- the first section is a floating hose (1 ) that is joined on one of its sides to the monobuoy (10), while the other end is enabled for the joining thereof to the discharge heads of the craft;

- the second section is a metal pipe with an inverted "L" shape that forms part of the welded structure that makes up the monobuoy; and

- the third section is a non-floating hose (2), or constrained hose, joined to the lower end of the monobuoy, with a length adapted to the mooring depth at the point at which the monobuoy is installed.

In one preferred embodiment, the floating hose (1 ) has a quick coupling on its joining end to the discharge pipes of the ships.

The second section comprises a side inlet flange (1 1 ) and a lower outlet flange (13) connected to each other. Thus, the second section is adapted to receive the discharge flow from the floating pipe (1 ) via the inlet flange (1 1 ) located on one side of the monobuoy and redirect it to the vertical to transfer it to the non-floating hose (2) through the outlet flange (13). Optionally, the second section is a curved metal tube that extends between both flanges (1 1 , 13).

Preferably, the three sections are joined by means of screwed flanges. The hose (2) can be similar to the one used by refineries, often used in sand discharges for beach regeneration, without flotation. Moreover, any plastic, rubber or metal tube with a suitable diameter can be used as an alternative that is lighter and easier to handle. However, it is recommended that it be made from divided sections that are flanged in order to facilitate the transportation and installation thereof.

These divided sections can be slightly flexible in order to adapt to the working conditions. Furthermore, the hose (2) independently has a mooring system (3).

Advantageously, the configuration herein described makes it so that in order to connect the monobuoy to the ship, hopper or dredger that is going to discharge, it is enough to only drag the floating hose (1 ), and not the entire assembly, since there is no load transfer of the section that remains submerged.

Another advantage of the use of the floating hose (1 ) with respect to a rigid pipe suspended on the buoy is that it prevents interference with the signaling systems, located on the upper surface of the monobuoy, in particular a vertical sign (16) that, in accordance with IALA, includes an "X" mark (Saint Andrew's Cross), a polyhedral radar reflector and a light source or lamp, which must be yellow by law, just like the color of the monobuoy body. The lamp is configured to emit a blinking light signal and operates independently, powered by energy sources, such as, for example, renewable energy, which can be solar panels, wave energy generation equipment or other equipment for generating electricity through movement. Furthermore, during the periods of time when no material is discharged, the hose (1 ) can be gathered circling the monobuoy and it will be fastened to it. Finally, the pounding of the sea should not be a problem for the type of hose to be used due to its flexibility.

Structurally, the monobuoy is made of two symmetrical halves that are coupled by means of a screwed joint (14). In one preferred embodiment, one of the halves corresponds to the emptying circuit and the other to the watertight spaces for monitoring equipment. Furthermore, each half has a double hull that has sufficient flotation volume in the case that a breach occurs in the outer hull of the monobuoy, such that it does not sink. In this regard, the buoyancy characteristics of the monobuoy must correspond to the weight that must be supported given the chain or chains of the mooring system (3). Furthermore, dividing the buoy into two bodies facilitates the transportation thereof in ISO standard containers of 6 or 12 meters (20 or 40 feet).

The geometry of the monobuoy is especially designed to reduce the force that the structure has against the currents and waves. As shown in the figures in plan view, the outside thereof has an approximately oval shape, which allow the buoy to orient itself with the currents, reducing the pounding of the waves. Nevertheless, anti-impact systems are provided which include rubber belts or protection straps (15) arranged on the outside of the buoy to avoid possible impacts with floating elements or with the ships during the discharge maneuver.

The monobuoy has the capacity to monitor the discharge point and the surroundings thereof, gathering ocean and meteorological data, so that it can self-validate the correct operation thereof. For this reason, the monobuoy incorporates monitoring means that include a system for sampling at different depths, different sensors for ocean and meteorological characterization, an antenna and data transmission equipment and a power supply system made up of renewable energy converters and batteries.

Preferably, the upper part of the buoy has a non-slip surface to improve the work ergonomics and prevent the loss of tools.

Advantageously, some of the functions of the present monobuoy include marking the mooring point and also supporting and redirecting the discharge hose to the floor. In turn, the swing redistributes the material in a more uniform manner, preventing accumulations. Moreover, it is possible to carry out the subsequent sealing of the discharge point by means of clean materials. Uncontaminated sediment with a particle size similar to that of the floor used can be used as clean materials.

The monobuoy is especially advantageous for being able to discharge in an ecological manner without tainting the water column, in other words, without turbidity or dispersion of pollutants, in the dredgers that are able to discharge through the bow. In other word, those that do not have an opening on the keel and can discharge by impulsion through the bow, meaning that the monobuoy can be used in many current dredgers that could discharge in an ecological manner without the cost being too high.

The maneuver for discharging is the same used by traditional dredgers for discharging through the bow by means of floating hoses. In the case of the monobuoys, the hose is situated vertically, without reaching the floor.

To empty the material, the craft must include a low power pumping station. The requirements for pumping are minimal, where it is enough to supply water from the surroundings and drag the dredged material through it away from the craft and to the section of the pipeline.

During operation, the lower end of the hose (2) must remain at a distance with respect to the floor, otherwise a mound would be created in a localized area and could even block the emptying. The optimal distance from the lower end of the hose (2) to the bed will depend on different factors, including:

- the installation time (complete volume of material to be discharged);

- the depth at the point of installation, which conditions the mooring system and therefore, the swing radius of the buoy; if the radius is very large, the hose (2) can be moved closer to the bed and less dispersion will occur;

- the currents and/or the meteorological conditions that cause more or less forced dispersion, meaning that the hose (2) can be moved closer to or further from the bed.

However, generally and without creating any limitations, two measures are recommended: one for shallow depths up to 50 m and the other for depths greater than 100 m.

One preferred embodiment of the present invention relates to a system for discharging a dredged material from the barge of any vessel, hopper or dredger, that is going to discharge to the bed, minimizing dispersion of pollutants and turbidity, and facilitating the connection with the vessel and the discharge, comprising a floating monobuoy that is moored to one or more blocks and means for guiding material to the bed, where the means for guiding comprise three sections joined together, where:

- a first section is a floating hose (1 ) connected between the vessel and an inlet flange (1 1 ) located on one side of the monobuoy;

- a second section is a redirecting circuit of the material that forms an integral part of the monobuoy (10); and

- a third submerged section that consists of a non-floating hose (2) connected to an outlet flange (13) on the lower end of the monobuoy (10). Where the monobuoy (10) is made of two symmetrical halves that are coupled by means of a screwed joint (14) and where one of the halves of the monobuoy (10) comprises the second section.

Preferably, the blocks are an integral part of at least one mooring system (3) connected to eye bolts (12) of the monobuoy (10) to define a discharge area (20).

Furthermore, each mooring system (3) further comprises a chain with a first, lighter part and a second, heavier part located near the floor.

In one embodiment, the redirecting circuit of the material of the second section is a metal pipe with an inverted "L" shape that forms part of the welded structure that makes up the monobuoy. Alternatively, the redirecting circuit of the material of the second section is a curved metal pipe.

Preferably, the three sections are joined by means of screwed flanges. Preferably, the floating hose (1 ) has a quick coupling on its connecting end to the vessel.

Preferably, the hose (2) is independent of the mooring system (3).

Preferably, the hose (2) is made from divided sections that are flanged, enabling it to be adapted to the mooring depth at the point at which the monobuoy is installed.

Furthermore, each half of the monobuoy (10) has a double hull that has sufficient flotation volume in the case that a breach occurs in an outer hull of the monobuoy.

The monobuoy (10) has an outside with an approximately oval shape. During the operation of discharging the material, the vessel has a low power pumping station.

In a manner that is consistent with the prior system, the present invention further protects a monobuoy for discharging a dredged material from the barge of any vessel, hopper or dredger, that is going to discharge to the bed, minimizing dispersion of pollutants and turbidity, and facilitating the connection with the vessel and the discharge, which is moored to one or more blocks and works together with means for guiding material to the bed, such that the monobuoy (10) is made of two halves that are coupled by means of a screwed joint (14) and where one of the halves of the monobuoy (10) comprises a second section of the means for guiding material; said means comprise three sections joined together, where:

- the second section is a redirecting circuit of the material that forms an integral part of the monobuoy (10); and

- a third submerged section that consists of a non-floating hose (2) connected to an output flange (13) on the lower end of the monobuoy (10).

In one embodiment, the redirecting circuit of the material is a metal pipe with an inverted "L" shape that is part of the welded structure that makes up the monobuoy.

In an alternative embodiment, the redirecting circuit of the material is a curved metal pipe.

Preferably, it incorporates monitoring means of the discharge point and the surroundings thereof, gathering ocean and meteorological data, which comprise:

- a system for sampling at different depths;

- different sensors for ocean and meteorological characterization;

- an antenna and data transmission equipment; and

- a power supply system made up of renewable energy converters and batteries.

Furthermore, according to the IALA regulations, the monobuoy has a lamp that is configured to emit a blinking yellow light signal and operates independently, powered by renewable energy converters and batteries.

Claims

1 . A system for discharging a dredged material from the barge of any vessel, hopper or dredger, that is going to discharge to the bed, comprising a floating monobuoy that is moored to one or more blocks and means for guiding material to the bed, CARACTERIZED in that the means for guiding material comprise three sections joined together, where:

a) a first section is a floating hose (1 ) connected between the vessel and an input flange (1 1 ) located on one side of the monobuoy;

b) a second section is a redirecting circuit of the material that forms an integral part of the monobuoy (10); and

c) a third submerged section that consists of a non-floating hose (2) connected to an output flange (13) on the lower end of the monobuoy (10); where the monobuoy (10) is made of two symmetrical halves that are coupled by means of a screwed joint (14) and where one of the halves of the monobuoy (10) comprises the second section.

2. The system of claim 1 , CHARACTERIZED in that the blocks are an integral part of at least one mooring system (3) connected to eye bolts (12) of the monobuoy (10) to define a discharge area (20).

3. The system of claim 2, CHARACTERIZED in that each mooring system (3) further comprises a chain with a first, lighter part and a second, heavier part located near the floor.

4. The system of claim 1 , CHARACTERIZED in that the redirecting circuit of the material of the second section is a metal pipe with an inverted "L" shape that forms part of the welded structure that makes up the monobuoy.

5. The system of claim 1 , CHARACTERIZED in that the redirecting circuit of the material of the second section is a curved metal pipe.

6. The system of claim 1 , CHARACTERIZED in that the three sections are joined by means of screwed flanges.

7. The system of claim 1 , CHARACTERIZED in that the floating hose (1 ) has a quick coupling on its connecting end to the vessel.

8. The system of claim 1 , CHARACTERIZED in that the hose (2) is independent of the mooring system (3).

9. The system of claim 1 , CHARACTERIZED in that the hose (2) is made from divided sections that are flanged, enabling it to be adapted to the mooring depth at the point at which the monobuoy is installed.

10. The system of claim 1 , CHARACTERIZED in that each half of the monobuoy (10) has a double hull that has sufficient flotation volume in the case that a breach occurs in an outer hull of the monobuoy.

1 1 . The system of claim 1 , CHARACTERIZED in that the monobuoy (10) has an outside with an approximately oval shape.

12. The system of claim 1 , CHARACTERIZED in that for discharging the material, the vessel has a low power pumping station.

13. A monobuoy for discharging a dredged material from the barge of any vessel, hopper or dredger, that is going to discharge to the bed, which is moored to one or more blocks and works together with means for guiding material to the bed, CHARACTERIZED in that it is made of two halves that are coupled by means of a screwed joint (14) and where one of the halves of the monobuoy (10) comprises a second section of the means for guiding material; said means comprise three sections joined together, where:

b) the second section is a redirecting circuit of the material that forms an integral part of the monobuoy (10); and

c) a third submerged section that consists of a non-floating hose (2) connected to an output flange (13) on the lower end of the monobuoy (10).

14. The monobuoy of claim 13, CHARACTERIZED in that the redirecting circuit of the material is a metal pipe with an inverted "L" shape that forms part of the welded structure that makes up the monobuoy.

15. The monobuoy of claim 13, CHARACTERIZED in that the redirecting circuit of the material is a curved metal pipe.

16. The monobuoy of claim 13, CHARACTERIZED in that each half of the monobuoy (10) has a double hull that has sufficient flotation volume in the case that a breach occurs in an outer hull of the monobuoy.

17. The monobuoy of claim 13, CHARACTERIZED in that it comprises monitoring means of the discharge point and the surroundings thereof, gathering ocean and meteorological data, which comprise:

a) a system for sampling at different depths;

b) different sensors for ocean and meteorological characterization;

c) an antenna and data transmission equipment; and

d) a power supply system made up of solar panels and batteries.

18. The monobuoy of claim 13, CHARACTERIZED in that it comprises a lamp that is configured to emit a blinking yellow light signal and operates independently, powered by solar panels and batteries.