WO2023227844A1

WO2023227844A1 - Ship for gathering floating algae

Info

Publication number: WO2023227844A1
Application number: PCT/FR2023/050723
Authority: WO
Inventors: Benjamin LERONDEAU
Original assignee: Efinor Sea Cleaner
Priority date: 2022-05-24
Filing date: 2023-05-22
Publication date: 2023-11-30

Abstract

A ship for gathering floating algae comprises a raising system (1) for bringing the algae up on board the ship in a working position in which an entry zone is below the waterline of the ship, the ship being characterized in that the raising system (1) can be moved between the working position and a stowed position in which the entry zone (E) is above the waterline (F).

Description

DESCRIPTION

TITLE: VESSEL FOR COLLECTING FLOATING ALGAE

Domain

The invention relates to a vessel for collecting floating algae, in particular sea lettuce or sargassum. anterior

Phenomena of proliferation of so-called green algae occur very frequently in certain coastal regions, with the conjunction of environmental and geographical factors. These algae are also called sea lettuce and are of the genus “Ulva”. Depending on weather phenomena, they can fail and accumulate along certain beaches and enter a putrefactive phase, making visiting these beaches unpleasant, or even dangerous due to the release of hydrogen sulphide.

In addition to efforts to limit the causes of proliferation, it is necessary to collect algae accumulations before they decompose. Until now, this collection is carried out by tractors which drive on the beaches. However, it was noted that the rolling of vehicles on the beaches had a deleterious effect on their natural environment.

In other regions, sargassum is the problem. Sargassum can form drifting islets on the surface of the sea. It happens that these islets wash up on the coast. If the coastline is busy, it is often necessary to be able to evacuate this organic matter.

We know from the document CN206902678U a vessel for collecting algae comprising a front subdivided into two hulls and between which a lifting system is placed. The lift system is a looped mat, installed with an incline such that the front of the lift system dips below the water surface. The movement of the belt allows floating algae to be lifted up and stored in tanks on the ship.

We note that the capabilities of this vessel are limited, particularly in terms of processing width and the possibility of approaching the coastline.

The invention aims to provide an algae collection vessel which is productive and particularly suitable for intervention as close as possible to the coast.

With these objectives in view, the invention relates to a vessel for collecting floating algae comprising a lifting system for raising algae onto the vessel in a working position in which an entry zone is below 'a flotation level of the ship, the ship being characterized in that the lifting system is movable between the working position and a storage position in which the entry zone is above the flotation level.

By using a mobile lifting system between a working position and a storage position, it is possible to give the lifting system a large width, which allows for high collection efficiency. In addition, this makes it easier to maneuver the vessel outside of collection operations, because the lifting system does not interfere with the storage position.

According to an improvement, the entry zone comprises at least one stop wheel intended to come to rest on the seabed so as to determine the working position of the lifting system. With a vessel whose lifting system includes a stop wheel, the lifting system can be operated as close as possible to the seabed and pick up any algae that rests on the bottom. This is made possible by the mobility of the lift system. In practice, several thrust wheels are used to provide support whatever the rolling position of the ship.

According to a constructive arrangement, the lifting system comprises at least one belt loop driven such that an upper strand of the loop moves from bottom to top. In the forward movement of the ship, the algae are moved to the upper strand of the loop and this carries the algae with it upwards to be loaded onto the vessel. The mat is for example an assembly of chain sleepers leaving spaces between the sleepers for the flow of water and retaining only the algae.

According to a constructive arrangement, the lifting system comprises a frame pivotally mounted on a hull of the ship along a lifting axis, the frame comprising a front crosspiece parallel to, and opposite to, the lifting axis, the front crosspiece carrying the thrust wheel. Changing from the working position to the storage position is a simple pivot, which is easy to achieve. According to an improvement, the frame pivots between the working position and the storage position over an angle greater than 210°, preferably greater than 230°. Thus, it is possible to place the frame of the ascent system substantially horizontally in the storage position, which avoids creating a visual obstacle in the pilot's field of vision and also limits the elevation of the center of gravity. In the working position the frame can be inclined between 30 and 60° relative to the horizontal.

According to a constructive arrangement, the lifting system comprises at least one lifting mechanism comprising a pair of links articulated together, a first of the links being articulated on the hull, a second of the links being articulated on the frame, the lifting mechanism comprising in addition a first cylinder pivotally mounted on the one hand on the hull and on the other hand on a pivot fixed on one of the links. The link mechanism allows the translational movement of the cylinder to be transformed into pivoting of the frame.

According to an improvement, the lifting mechanism further comprises a second cylinder pivotally mounted on the one hand on the hull and on the other hand on a pivot fixed on one of the links, the second cylinder being configured to act in an oblique direction relative to the axis of the first cylinder when the mechanism is in a position in which the first cylinder is close to a cusp point. When the first link pivots, a turning point is reached, beyond which the translational movement of the cylinder reverses. At the cusp, the cylinder can no longer transmit pivoting torque. By adding a second cylinder, we can thus control the pivoting of the links beyond the cusp point and thus, we can increase the amplitude of the controlled movement.

According to another characteristic, the ship comprises a collection system for directing the harvested algae towards at least one storage container, the collection system comprising at least one lateral conveyor belt providing a lateral movement intended to receive the algae raised by the transport system. ascent. The lateral conveyor belt thus allows the collected algae to be refocused. In particular, two mats can be used which bring the algae from each edge towards the center.

According to an improvement, the collection system includes a hopper for distributing the algae collected downstream of the lateral conveyor belt to at least two containers. The hopper can be fed directly or by a hopper conveyor belt which receives the algae at the end of the side conveyor belt(s). By distributing the collection to several containers, we can manage the change of containers without interrupting the collection. According to an improvement, the hopper is removable. We can therefore organize the collection differently, in particular by directly loading a large container.

According to another characteristic, the ship has at least two motorized front wheels on either side of the lifting system. This gives the ship amphibious capabilities, which allows it to get fairly close to the coast and have the means to escape from a grounding.

According to an improvement, the front wheels are steerable. It is thus possible to steer the front of the ship when the wheels are resting on the seabed.

According to another improvement, the front wheels are motorized independently of each other. In addition to or instead of the steerability of the wheels, it is possible to also steer the ship by acting on the difference in movement between the wheels.

According to another characteristic, the ship includes at least one rear wheel at one end of the ship opposite the lifting system. The ship is thus able to roll while being completely out of the water.

According to another characteristic, the ship includes a powertrain and a cooling system comprising an exchanger integrated into the hull to cool the powerplant. Cooling is achieved directly by contact between the hull and the water. Thus, the powertrain is not dependent on a cooling circuit created by pumping water which could be blocked by algae.

According to one embodiment, the vessel includes a central well to receive the harvested algae. The central well forms a tank in which the algae can be stored.

According to an improvement, the central well is in fluid communication with the underside of the ship. The central well is able to contain sea water, so that the algae remain floating in this water. This is particularly useful for unloading, particularly by pumping, in which the water that is pumped serves as a vector for transporting the algae. In addition, the balance of the ship is not modified by its loading, it maintains a constant waterline and stability whatever the loading level.

According to a constructive arrangement, the central well has a grid delimiting its bottom. The size of the mesh of the grid can be adapted to the nature of the algae collected. The exchange of water volume can be very rapid in one direction or the other, which allows the stability of the vessel. Brief description of the figures

The invention will be better understood and other particularities and advantages will appear on reading the description which follows, the description referring to the appended drawings among which:

• Figure 1 is a perspective view of a ship conforming to a first embodiment of the invention in working position;

• Figure 2 is a view similar to Figure 1 in which a lifting system is in the storage position;

• Figure 3 is a top view of the ship of Figure 1;

• Figure 4 is a side view of the ship of Figure 1;

• Figure 5 is a schematic view of the powertrain cooling circuit;

• Figure 6 and a partial view of the front of the ship showing in particular the lifting system in the stowed position;

• Figure 7 is a view similar to Figure 6 in an intermediate position between a working position and the storage position;

• Figure 8 is a view similar to Figure 6 with the lifting system in the storage position;

• Figure 9 is a view similar to Figure 4 of a ship according to a second embodiment of the invention;

• Figure 10 is a detailed perspective view of the ship of Figure 9.

A vessel for collecting floating algae in accordance with a first embodiment of the invention is shown in Figures 1 to 4. The vessel includes a lifting system 1 for raising algae onto the vessel, placed at the bow of the ship. The ship also includes a pilot cabin 2, a hydraulic unit 3 capable of putting a hydraulic fluid under pressure, two propulsion assemblies with steerable and lifting propellers. Each propeller is driven by a motor receiving the hydraulic fluid supplied by the hydraulic unit 3. A bridge 4 extending between the cabin 2 and the lifting system 1 makes it possible to receive flexible bins 5, 5' intended to contain the harvested algae.

The ship has at least two motorized front wheels 6 on either side of the lifting system 1 and two rear wheels 7 on either side of the cabin 2 at one end of the ship opposite the lifting system 1. The wheels before 6 are adjustable. The front wheels 6 and the rear wheels 7 are motorized independently of each other. The wheels 6, 7 protrude from the bottom of the vessel at a height typically between 20 and 50 cm.

The lifting system 1 comprises a frame 10 pivotally mounted on a hull 8 of the ship along a lifting axis R, the frame 10 comprising a front crosspiece 101 parallel to, and opposite to, the lifting axis R. lifting system 1 comprises three belt loops 12 arranged side by side on the frame 10 and extending between an entry zone E and an exit zone S. The belt loops 12 are driven by a hydraulic motor powered from the hydraulic unit so that an upper strand of the loop moves from bottom to top.

The lifting system 1 is movable between a working position I and a storage position IL. In the working position of the lifting system 1, as shown in Figures 1, 3, 4 and 8, the entry zone is at -below a waterline level F of the ship. In the storage position, as shown in Figures 2 and 6, the entry zone E is above the flotation level F. The frame 10 passes from the working position to the storage position by pivoting around the rise axis R over an angle greater than 210°.

The entry zone E comprises four stop wheels 11 carried by the front crosspiece 101 and intended to come to rest on the seabed so as to determine the working position of the lifting system 1.

The lifting system 1 comprises a lifting mechanism 13 comprising a pair of links 131, 132 articulated together on an axis 137, a first of the links 131 being articulated on the shell 8, a second of the links 132 being articulated on the frame 10 on a pivot 136. The lifting mechanism 13 further comprises a first cylinder 133 pivotally mounted on the one hand on the hull 8 and on the other hand on a pivot 135 fixed on the first link 131. The lifting mechanism 13 comprises in in addition to a second cylinder 134 pivotally mounted on the one hand on the shell 8 and on the other hand on a pivot 135 fixed on the first link 131, the second cylinder 134 being configured to act in an oblique direction relative to the axis of the first cylinder 133 when the mechanism is in a position in which the first cylinder 133 is close to a cusp. The cusp is characterized by the alignment in the same plane of the pivot 135 with the mounting axis of the first link 131 on the shell 8 and the mounting axis of the first cylinder 133 on the shell 8. In practice, the first cylinder 133 extends in one direction substantially horizontal. The first and second cylinder 133, 134 pivot on the same axis 135 linked to the first link 131.

On deck 4, the ship has a collection system 9 to direct the collected algae towards storage containers 5, 5'. The collection system 9 has two side conveyor belts

91 providing a lateral movement intended to receive the algae raised by the lifting system 1. The two lateral conveyor belts 91 operate opposite each other to bring the algae towards the center of the vessel on a central conveyor belt 92.

In a first configuration, as shown in Figure 1, the collection system 9 further comprises a hopper 93 for distributing the algae collected by the central conveyor belt

92 towards three containers 5. The containers 5 are for example thick textile bags provided with handles to hold them in position during filling and for their handling. The supply of each of the containers 5 can be closed by a hatch to be able to change the container 5 while the filling of the others continues. When a container 5 is full, it can be moved using a handling crane to be placed in a storage location on deck 4.

The hopper 93 is removable to move into a second configuration. In this second configuration, the filling is carried out in a large container 5', as shown in Figure 2. When the large container 5' is filled, a capstan and a sling are used to slide the container 5' onto the deck 4 and place it in a storage location. Another large empty 5' container is then put in place to resume collection operations.

The hydraulic unit 3 comprises a cooling system 30 comprising two exchangers 301, 302 integrated into the hull 8 below the waterline to cool the hydraulic unit 3, as shown schematically in Figure 5. One of the exchangers 301 is connected to a cooling circuit for a heat engine, while the other of the exchangers 302 is connected to another cooling circuit 30 for the hydraulic pump. The heat exchange is carried out through the wall of the hull 8 with the water in which the ship floats.

The vessel is designed for the recovery of green algae near the coast in areas with shallow draft. When the lifting system 1 is in the working position, the thrust wheels 11 are supported on the seabed and the hydraulic pressure in the cylinders is released so that the movement of the frame 10 is free. 12 carpet loops are driven so as to raise the algae above deck 4 at the level of the bow of the ship. The algae are then dumped onto the side conveyor belts 91, then onto the central conveyor belt 92 and finally into the hopper 93. From the hopper 93, the algae are distributed into the different containers 5. When one of the containers 5 is full , a hatch allows its supply to be closed and the container 5 is moved to deck 4 using the crane 40 to be replaced by an empty container 5. The hatch is opened again to resume filling container 5.

In the open sea, the ship slaloms across a patch of algae. Close to the bank, a back and forth perpendicular to the bank allows the collection of algae. The stop wheels 11 make it possible to follow the bathymetry of the bottom. If necessary, the ship can roll on the bank, possibly relying only on the front wheels 6 or on all the wheels. Wheels 6, 7 also allow the vessel to move even if the water has receded.

When the collection work is completed, the lifting system 1 passes from the working position, as shown in Figure 6, to the storage position, as shown in Figure 8. To do this, the output of the second cylinder 134 which actuates the first link 131 in a pivoting in the counterclockwise direction as seen in Figures 6 to 8. The first link 131 exerts traction on the second link which thus causes the pivoting of the frame 10 in the anticlockwise direction -hourly. At the same time, the retraction of the first cylinder 133 is controlled. When the frame 10 is in an intermediate position as shown in Figure 7, the operation of the second cylinder 134 is released so as to allow the continuation of the movement of the first cylinder 133 , until reaching the storage position II as shown in Figure 8. The deployment towards the working position I follows a reverse movement.

In a second embodiment, as shown in Figures 9 and 10, the ship differs from the first embodiment in that it includes a central well 80 to receive the harvested algae. The central well 80 forms a tank in which the algae can be stored. The central well 80 includes a grid 801 delimiting its bottom, such that the central well 80 is in fluid communication with the underside of the ship. The hull 8' thus forms two floats 81 on either side of the central well 80.

During use, the algae coming from the collection system 9 are discharged directly into the central well 80 by the central conveyor belt 91. The vessel is equipped with a transfer system, not shown, comprising a pump for sucking up the mixture of water and algae in the central well 80 to evacuate the algae and reject the mixture towards a installation in another vessel or at dock. This type of collection is particularly well suited to collecting sargassum.

Claims

CLAIMS Vessel for collecting floating algae comprising a lifting system (1) for lifting algae onto the vessel in a working position in which an entry zone is below a waterline level of the vessel, the vessel being characterized in that the lifting system (1) is movable between the working position and a storage position in which the entry zone (E) is above the waterline level (F). Vessel according to claim 1, in which the entry zone comprises at least one stop wheel (11) intended to come to rest on the seabed so as to determine the working position of the lifting system (1). Vessel according to claim 1 or 2, wherein the lifting system (1) comprises at least one carpet loop (12) driven such that an upper strand of the loop moves from bottom to top. Ship according to one of claims 2 or 3 in combination with claim 2, in which the lifting system (1) comprises a frame (10) pivotally mounted on a hull (8) of the ship along a lifting axis (R) , the frame (10) comprising a front crosspiece (101) parallel to, and opposite, the lifting axis (R), the front crosspiece (101) carrying the thrust wheel (11). Vessel according to claim 4, in which the frame (10) pivots between the working position and the storage position over an angle greater than 210°, preferably greater than 230°. Vessel according to one of claims 4 or 5, in which the lifting system (1) comprises at least one lifting mechanism (13) comprising a pair of links (131, 132) articulated together, a first of the links (131 ) being articulated on the hull (8), a second of the links (132) being articulated on the frame (10), the lifting mechanism (13) further comprising a first cylinder (133) pivotally mounted on the one hand on the shell (8) and on the other hand on a pivot (135) fixed on one of the links (131, 132). Vessel according to claim 6, in which the lifting mechanism (13) further comprises a second cylinder (134) pivotally mounted on the one hand on the hull (8) and on the other hand on a pivot (135) fixed on the one of the links (131, 132), the second cylinder (134) being configured to act in a direction oblique to the axis of the first cylinder (133) when the mechanism is in a position in which the first cylinder (133) is close to a cusp.

8. Vessel according to one of the preceding claims, characterized in that it comprises a central well (80) to receive the harvested algae.

9. Vessel according to claim 8, wherein the central well (80) is in fluid communication with the underside of the vessel.

10. Vessel according to claim 9, in which the central well (80) comprises a grid (801) delimiting its bottom.

11. Vessel according to one of claims 1 to 7, characterized in that it comprises a collection system (9) for directing the harvested algae towards at least one storage container (5), the collection system (9) comprising at least one lateral conveyor belt (91) providing lateral movement intended to receive the algae raised by the lifting system (1).

12. Vessel according to claim 11, in which the collection system (9) comprises a hopper (93) for distributing the algae collected downstream of the lateral conveyor belt (91) to at least two containers (5).

13. Vessel according to claim 12, wherein the hopper (93) is removable.

14. Vessel according to one of the preceding claims, characterized in that it comprises at least two motorized front wheels (6) on either side of the lifting system (1).

15. Ship according to claim 14, in which the front wheels (6) are steerable.

16. Ship according to one of claims 14 or 15, in which the front wheels (6) are motorized independently of one another.

17. Vessel according to one of claims 14 to 16, characterized in that it comprises at least one rear wheel (7) at one end of the vessel opposite the lifting system (1).

18. Ship according to one of the preceding claims, characterized in that it comprises a hydraulic unit (3) and a cooling system (30) comprising an exchanger integrated into the hull (8) to cool the hydraulic unit (3) .