Improved efficiency seaweed harvesting device

Abstract

The invention relates to a seaweed harvesting device (SWD) according to an advantageous embodiment of the invention, comprising: a harvesting comb (PC) comprising a plurality of flat blades (LP1, LP2…LPn) substantially parallel to each other and attached to a frame (CS) encompassing said blades; and traction means (FT1, FT2, PC) for said frame (CS). According to the invention, the blades (LP1, LP2…LPn) are attached to the frame (CS) by means of fastening means (FX) allowing adjustment of the spacing (PR) between said blades. The invention makes it possible to adjust the spacing (PR) between the blades (LP1, LP2…LPn) to the size of the seaweed to be collected. Reference: Figure 1

Description

Title of the invention: Improved efficiency seaweed harvesting device for seaweed harvesting

[0001] The invention relates generally to a device for collecting seaweed at sea. Technical field

[0002] The invention falls within the general field of preservation and enhancement of the marine environment, and more particularly within the field of the cultivation, harvesting and processing of algae for the purpose of their enhancement. Previous technique

[0003] A seaweed collection device is known from French patent FR 3001103. This document describes a dredge including a collection comb comprising a plurality of flat blades substantially parallel to each other and attached to a frame encompassing said blades, and means for pulling said frame in a direction substantially parallel to said blades.

[0004] This dredge is designed to be placed and moved along the seabed by towing from a surface vessel, for example, an oyster barge. The algae to be collected, which will generally be so-called "green" algae, also known as "Ulva," are suspended in the water and become trapped between the blades of the collecting rake when the dredge is set in motion. The dredge is then simply lifted out of the water and emptied by tilting it to cause the algae to be discharged into a tank, for example, a barge positioned at the end of the oyster barge.

[0005] The algae to be collected vary in size, are adherent, even sticky, and tend to quickly clog the collection combs of known harvesting equipment, thus reducing their productivity. Furthermore, the device described above is designed to rest on the seabed, and its movement, although facilitated by ski-like skids, is likely to significantly degrade the local ecosystem. Moreover, the algae to be collected have the particular property of being able to detach very easily from the seabed and often form drifting clouds that can be found near the seabed, on the surface, or in midwater, depending on the relative densities of the water and the algae.These unattached algae continue to grow while drifting, so their volume will be considerably greater when they wash ashore, complicating their collection on land and increasing the nuisance they will then cause. However, the seaweed collection device known from French patent FR 3001103 is only designed to collect algae located near the seabed. Principle of the invention

[0006] The inventors, having identified the drawbacks inherent in the aforementioned prior art, have designed a collection device that will be less vulnerable to saturation due to the effects of algae clogging. Advantageously, a variant of this collection device will be capable of collecting algae not only near the seabed, but also at the surface or in midwater. Another variant of such a collection device will allow it to be moved along the seabed while limiting the disturbance caused by such movement to the local ecosystem. Summary of the invention

[0007] According to a first aspect, the present invention thus proposes a device for collecting seaweed at sea comprising: . a collection comb comprising a plurality of flat blades substantially parallel to each other and attached to a frame encompassing said blades; and . means for traction of said frame; device characterized in that the blades are secured to the frame by means of fixing allowing adjustment of a pitch separating said blades.

[0008] The invention makes it possible to adjust the space between the blades to the size of the algae to be collected. Indeed, since algae have a great variability in their dimensions depending on the time, species and place where they are observed, the invention advantageously makes it possible to adapt this spacing before harvesting.

[0009] According to an advantageous embodiment of the invention, the collection comb is made in the form of a self-contained box including all the blades and removable from the chassis.

[0010] This embodiment of the invention allows for easy and quick adjustment of the pitch of the collection comb, carried out by dismantling a box including blades having a certain pitch between them to replace it with another box including blades having a different pitch better suited to the configuration of the algae to be collected.

[0011] Alternatively, in other embodiments of the invention, the setting of the pitch of the collection comb may be achieved by means of an individual mounting / dismounting system for the blades.

[0012] According to a particular embodiment of the invention, the spacing of the collection comb is greater than or equal to half the average dimensions of the algae to be collected. Such spacing between the blades produces optimal collection efficiency.

[0013] According to another particular embodiment of the invention, the blades of the comb are provided with front edges inclined towards the rear.

[0014] Such an embodiment of the blades facilitates the sliding of algae into the compartments they delimit as the device advances. At their base, the blades will preferably have a dimension at least equivalent to half the average size of the algae to be collected, in order to avoid their entanglement, that is to say the formation of knots of algae at the back of the blades which would be likely to hinder their extraction once the collection is completed.

[0015] According to a second aspect of the invention, the chassis having two outer sides substantially parallel to the blades of the collection comb, the traction means include a traction fork composed of two symmetrical arms, each having one end connected by means of a pivot link to one of the sides of the chassis, the other ends of said arms being connected together in a central part intended to cooperate with a traction member.

[0016] Such an embodiment of the traction means allows a pivoting of the traction fork which will naturally adopt an inclination parallel to an instantaneous angle at which the traction force will be exerted on the traction means, which promotes the vertical stability of the device during its operational implementation.

[0017] According to an advantageous embodiment of this second aspect, said pivot links are located at a height greater than the position adopted by the center of gravity of the device, on the one hand, and set back from said position of the center of gravity with respect to a direction of traction force exerted on said device when it is in operational use, on the other hand.

[0018] Such an arrangement of the pivot links makes it possible to further increase the vertical stability of the device during its operational implementation, the traction force exerted on the device when it is towed from a surface vessel generating by reaction on the front part of the device a downward vertical force.

[0019] According to a particular embodiment of this second aspect of the invention, the chassis is provided in the upper part with an anchor point to which the traction member must be attached, and the central part of the fork includes an opening intended to be traversed by said traction member.

[0020] Such an embodiment makes it possible to pull the top of the front part of the collection device downwards when the traction force is exerted, and thus to compensate for the vertical component inherent in this traction force when it is exerted by a surface vessel while the device rests on the seabed.

[0021] According to a particularly advantageous embodiment of this second aspect of the invention, the central part of the traction fork is provided with a hooking loop, the arms of said traction fork having a length greater than a distance separating the locations of the pivot links from an edge of the chassis which is furthest away from it.

[0022] Such an embodiment allows the chassis of the device to tilt relative to the fork when the central part of the latter is pulled upwards, for example in order to cause the accumulated contents between the comb blades during collection operations to spill out.

[0023] According to a particularly advantageous embodiment of the invention, a device such as described above further includes at least one ballast capable of compensating for all or part of the weight of the device when it is immersed.

[0024] Such an implementation method will allow the device according to the invention to carry out collections by moving not only on the seabed, but also between two waters as well as on the surface depending on the configurations of the algae fields to be collected.

[0025] According to another particularly advantageous embodiment of the invention, a device such as described above further includes a running gear arranged in the lower part of the chassis.

[0026] Such an implementation method not only allows for relatively environmentally friendly movement of the device on the seabed ecosystem, but also for easier movement of the device out of the water. Advantageously, the rolling elements included in the running gear will have an adjustable height.

[0027] According to yet another particularly advantageous embodiment of the invention, a device such as described above further includes at least one wing-profile stabilizer bar arranged transversely with respect to a direction of movement of the device.

[0028] Such a stabilizer bar may be mounted at the front and / or rear of the chassis, and will advantageously be adjustable according to speed, angle of traction and sea state, to improve the stability of the collection device. Brief description of the drawings

[0029] Other features and advantages of the invention will become more apparent upon reading the following description of a particular embodiment, given by way of illustrative and non-limiting example, and with reference to the accompanying drawings, among which: Fig. 1

[0030] [Fig.1] is a perspective view of a collection device according to an advantageous embodiment of the invention; Fig. 2

[0031] [Fig.2] is a front view of this collection device; Fig.3

[0032] [Fig.3] is a functional diagram that represents two interchangeable trays allowing adjustment of the comb pitch in a collection device according to the invention; Fig. 4

[0033] [Fig.4] is a diagram which represents, from the left view, a collection device conforming to the invention during operation; Fig. 5

[0034] [Fig.5] is a diagram which represents, from the left view, a collection device conforming to the invention being hoisted; Fig. 6

[0035] is a diagram which represents, in left-hand view, a collection device according to the invention in the emptying position; and Fig. 7

[0036] [Fig.7] is a diagram which represents, from the left view, a collection device in accordance with the invention during operation between two waters. Description of the implementation methods

[0037] Figures 1 and 2, considered together, represent a DSP device for collecting seaweed at sea according to an advantageous embodiment of the invention, including: a PC collection comb comprising a plurality of flat blades (LP1, LP2...LPn) substantially parallel to each other and attached to a CS frame encompassing said blades; and . traction means (FT1, FT2, PC) of said chassis.

[0038] According to the invention, the blades (LP1, LP2.. .LPn) are secured to the chassis CS by means of FX fixing means allowing adjustment of a pitch PR separating said blades.

[0039] The invention allows the spacing PR between the blades to be adjusted to the size of the algae to be collected. Since algae exhibit significant variability in size depending on the time, species, and location of observation, the invention advantageously allows this spacing to be adjusted before harvesting. In this embodiment of the invention, it is sufficient to remove every other blade (LP2, LP4...LPn-1) to double the spacing of the collection comb.

[0040] Preferably, the spacing of the collection comb will be adjusted to be greater than or equal to half the average dimensions of the algae to be collected. The inventors' work has indeed enabled them to determine that such a spacing between the blades produces optimal collection efficiency.

[0041] In the embodiment shown here, the fastening means consist of corner strips, each having two orthogonal lengths, one of which is fixed to the CS frame and the other onto which one end of a flat blade (LP1, LP2...LPn) can be screwed. Thus, each flat blade is easily removable and re-mountable.

[0042] In the embodiment of the invention shown here, the chassis CS has two outer sides substantially parallel to the blades (LP1, LP2...LPn) of the collection comb PC, and the traction means include a traction fork composed of two symmetrical arms (FT1, FT2), each having one end connected by means of a pivot joint (PV) to one of the sides of the chassis CS. The other ends of said arms (FT1, FT2) are connected together in a central part PC intended to cooperate with a traction element OT, which in this example consists of a chain attached to an anchor point AT located at the top of the chassis CS, and which passes through a tube integral with the central part PC of the traction fork. Two oblique bars OBI and OB2 further form a hook GA, the purpose of which will be explained later in the description.

[0043] The DSP device described herein further includes a TRL running gear arranged in the lower part of the CS chassis, which not only allows for relatively environmentally friendly movement of the device on the seabed, but also facilitates the removal of the DSP device from the water. Advantageously, the rolling elements included in the TRL running gear have an adjustable height, for example by means of a set of interchangeable wheels of different diameters.

[0044] Fig. 3 is a functional diagram which represents an alternative embodiment of the invention to that which has been described above, in which the collection comb is made in the form of a self-contained box including all the blades and removable from the chassis.

[0045] This embodiment of the invention allows for easy and quick adjustment of the pitch of the collection comb, carried out by dismantling a box (CAI or CA2) including blades having a certain pitch between them (PR1 or PR2) to replace it with another box (CA2 or CAI) including blades having between them another (PR2 or PR1) pitch better adapted to the configuration of the algae to be collected.

[0046] The first and second interchangeable cassettes (CAI, CA2) have identical external dimensions so that both can be inserted into the same housing provided in the CS chassis of the DSP device. In the example described here, the comb formed by the first cassette CAI comprises three blades delimiting four inter-blade spaces, while the comb of the second cassette CA2 comprises five blades delimiting six inter-blade spaces for the same cassette width, which implies that the PR2 pitch of the comb formed by the second cassette CA2 is equal to two-thirds of the PR1 pitch of the comb formed by the second cassette CA2

[0047] Figure 4 schematically represents, from the left, a DSP collection device in operation. In this embodiment, the traction means include a traction fork composed of two symmetrical arms, only one of which A branch FT2 is visible in the figure. One end of each branch is connected by means of a pivot link PV to one of the sides of the chassis CS, the other ends of said branches being connected together in a central part PC intended to cooperate with a traction element OT.

[0048] Such an embodiment of the traction means allows a pivoting of the traction fork which will naturally adopt an inclination parallel to an instantaneous angle [3 at which the traction force ET will be exerted on the traction means, which promotes the vertical stability of the DSP device during its operational implementation.

[0049] In the advantageous embodiment described here, said pivot links PV are located at a height greater than the position adopted by the center of gravity CDG of the device, on the one hand, and set back from said position of the center of gravity CDG with respect to a direction of traction force ET exerted on said device DSP when it is in operational use, on the other hand.

[0050] Such an arrangement of the PV pivot links makes it possible to further increase the vertical stability of the device during its operational implementation, the traction force ET exerted on the DSP device when it is towed from a surface vessel generating by reaction on the front part of the DSP device a downward vertical force.

[0051] In this advantageous embodiment of the invention, the chassis is provided at its upper part with an anchor point AP to which the traction member OT is to be attached, the central part PC of the traction fork comprising two openings intended to be traversed by said traction member OT, in this case the ends of a tube integral with said central part PC as shown in [Fig. 2]. In other embodiments of the invention, the tube may be replaced by a ring which will then delimit a single opening.

[0052] Such an embodiment makes it possible to pull the top of the front part of the DSP collection device downwards when the traction force ET is exerted, and thus to compensate for the vertical component specific to this traction force ET when it is exerted by a surface vessel while the DSP device rests on the seabed.

[0053] Finally, in this particularly advantageous embodiment of the invention, the DSP device further includes at least two wing-profile stabilizer bars SB1 and SB2 arranged transversely with respect to a direction of movement HZD of the DSP device.

[0054] These stabilizer bars SB1 and SB2 are mounted respectively at the front and rear of the CS chassis, and will advantageously be adjustable in height and inclination according to the speed, the angle of traction [3 and the state of the sea, to improve the stability of the DSP collection device.

[0055] Figures 5 and 6 schematically represent, from left view, a drainage sequence of a collection device according to a particularly advantageous embodiment of the invention, in which the central part of the traction fork is provided with a hook loop, the arms of said traction fork have a length greater than a distance separating the locations of the pivot links from an edge of the chassis that is furthest from it.

[0056] As illustrated in [Fig.5], when the DSP device is lifted vertically out of the water by means of a hook CR previously inserted in the hooking loop and connected to a traction device such as a crane placed on the boat which produced the traction force, the traction member OT is simultaneously kept under tension so that the traction fork adopts under the effect of gravity a substantially vertical orientation in line with the pivot joint AP, which causes the chassis to tilt backwards and thus ensures that the algae harvested inside it are kept in place during the transport of the DSP device to a disposal area, for example a tank placed on the deck of the towing boat.

[0057] As illustrated in [Fig. 6], when the DSP device reaches its discharge zone, the traction member OT is released, allowing the DSP device to tilt forward under the weight of the algae that have accumulated between the blades of the collection comb, primarily in the front part of the CS frame. Since the arms of the traction fork are longer than the distance between the pivot joint locations PV and the upper edges of the frame, the traction member OT can be allowed to unwind until the CS frame is sufficiently inclined to allow the ALV algae contained within it to be discharged by gravity.

[0058] This embodiment therefore does not require the implementation of any mechanical effort to empty the DSP collection device, except that required to lift it out of the water in order to bring it above a collection area.

[0059] Figure 7 schematically represents, from the left, a collection device capable of operating at different depths, and in particular suspended above the seabed (GND) as illustrated here. Indeed, in this embodiment, the DSP collection device as described above also includes at least one BLS ballast capable of compensating for all or part of the weight of the DSP device when it is submerged.

[0060] Such an implementation method will allow the device according to the invention to carry out collections by moving not only on the seabed, but also between two waters as well as on the surface depending on the configurations of the algae fields to be collected.

[0061] In the example shown here, the ballast BAL is connected to the chassis CS by means of links LV1 and LV2 which will preferably be of adjustable length, which will allow adjustment of the depth at which the collection device DSP will operate below the surface of the water SLV.

[0062] In addition to enabling collections on the seabed GND, on the surface SLV or between two waters, the ballast also has the advantage of forming a means of signaling the presence of the DSP device when it is submerged, and thus contributing to securing navigation in the vicinity of it.

Claims

Demands

1. Seaweed collection device, including: . a collection comb (PC) comprising a plurality of flat blades (LP1, LP2...LPn) substantially parallel to each other and attached to a frame (CS) encompassing said blades; and . traction means (TM) of said frame (CS); device characterized in that the blades (LP) are attached to the frame (CS) by means of fastening means (FX) allowing adjustment of a pitch (PR) separating said blades.

2. Collection device according to claim 1, characterized in that the collection comb (PC) is made in the form of a self-contained box including all the blades (LP) and removable from the chassis (CS).

3. Collection device according to any one of claims 1 or 2, characterized in that the pitch (PR) of the collection comb (PC) is greater than or equal to half the average dimensions of the algae to be collected.

4. Collection device according to any one of claims 1 to 3, characterized in that the blades (LP) of the collection comb (PC) are provided with rearward inclined front edges.

5. Collection device according to any one of claims 1 to 4, characterized in that, the chassis having two outer sides substantially parallel to the blades of the collection comb, the traction means (TM) include a traction fork composed of two symmetrical arms (FT1, FT2) each having one end connected by means of a pivot link (PV) to one of the sides of the chassis (CS), the other ends of said arms being connected together in a central part (PC) intended to cooperate with a traction member (TC).

6. Collection device according to claim 5, characterized in that said pivot links (PV) are implanted at a height greater than the position adopted by the center of gravity (CDG) of the device, on the one hand, and set back from said position of the center of gravity (CDG) with respect to a direction of traction force (ET) exerted on said device when it is in operational use, on the other hand.

7. Collection device according to one of claims 5 or 6, characterized in that the chassis is provided in the upper part with an anchor point (AP) to which the traction member (OT) is to be attached, and in that the central part (PC) of the fork includes an opening intended to be traversed by said traction member.

8. Collection device according to claim 7, characterized in that the central part (PC) of the traction fork is provided with a hook loop (GA), the arms (FT1, FT2) of said traction fork having a length greater than a distance separating the locations of the pivot links from an edge of the chassis (CS) which is furthest away from it.

9. Collection device according to any one of claims 1 to 8, characterized in that it further includes at least one ballast (BLS) capable of compensating for all or part of the weight of the device when it is immersed.

10. Collection device according to any one of claims 1 to 9, characterized in that it further includes a running gear (TRL) arranged in the lower part of the chassis (CS).

11. Collection device according to any one of claims 1 to 10, characterized in that it further includes at least one wing-profile stabilizer bar (SB1, SB2) arranged transversely with respect to a direction of movement (HZD) of the device.

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