PROCESS OF ELIMINATION OF SARGASS ALGAE AND COASTAL ZONE BY DEEP AND DEFINITIVE IMMERSION OF ALGAE

Abstract

A method for eliminating sargassum seaweed in coastal areas by deep and permanent immersion of the algae in the sea. The method involves giving the algae negative buoyancy by applying sufficient pressure, allowing for the degassing of the tissues and an increase in their density. This pressurization can be achieved through various methods, the common basic principle of which is the forced immersion of the algae to a certain minimum depth until it reaches a relative density greater than 1, thus eliminating its buoyancy and allowing its subsequent deep and permanent immersion in the sea by gravity alone.

Description

Title of the invention: METHOD FOR ELIMINATION OF SARGASSE ALGAE IN COASTAL AREA BY DEEP AND DEFINITIVE IMMERSION OF ALGAE

[0001] CONTEXT

[0002] Since the significant increase in the arrival of sargassum in the Caribbean in the 1990s, their stranding on coastal areas has posed serious environmental and navigation problems, as well as public health problems in inhabited coastal areas.

[0003] For several years, numerous techniques for managing sargassum beds have been tested and sometimes implemented: collection systems, floating barriers, floating or land-based crushing units, clap barge, etc., without an ideal solution having been identified or updated.

[0004] This patent presents a new technique for managing and eliminating sargassum directly at sea, without producing secondary waste.

[0005] PROPOSED TECHNICAL SOLUTION

[0006] This technical solution was the subject of the filing of the Soleau envelope number DSO2023005918. It offers a new solution for treating sargassum directly offshore.

[0007] The process consists of giving the algae negative buoyancy by applying sufficient pressure, allowing degassing of the tissues and an increase in their density.

[0008] This pressurization can be achieved by different processes, one of the principles of which The common base consists of a forced immersion of the algae to a certain minimum depth until it gives a relative density greater than 1, thus allowing its buoyancy to be cancelled and then allowing its deep and definitive immersion in the sea by simple gravity.

[0009] PRINCIPLE OF DEEP IMMERSION TREATMENT

[0010] This idea is based on the following principles: a. Sargassum, in its natural state, has positive buoyancy which allows it to drift on the surface of the oceans, aggregate into large patches, and then wash up on coastal areas. b. This positive buoyancy is the result of an assembly of organic matter, water and gases dissolved in the tissues of the algae. This buoyancy is slightly positive. c. The laws of thermodynamics (including Clapeyron's law: PV=nRT) predict that any compressible body subjected to increasing pressure, all other things being equal, sees its volume decrease inversely proportional to the pressure. If this body is immersed in a quasi-incompressible medium such as water, the famous Archimedes' law predicts that the buoyancy of this body will decrease inversely proportionally to the decrease in its volume. These two laws combined make it possible to theoretically explain a phenomenon well known to divers and freedivers: any compressible body with positive surface buoyancy (relative density <1), immersed to a certain depth, ends up exhibiting negative buoyancy (relative density >1), and begins to sink on its own in the water column by gravity. These principles of thermodynamics apply to Sargassum seaweed, which can be considered a compressible body.Brought to a certain depth by various technical means, some of which are described later, the sargassum algae will then complete its immersion on its own, by simple gravity, until it reaches the ocean floor.

[0011] In July 2023, a test bench was set up to confirm the reality of this principle. The tests were carried out over the period August / September 2023. This experimental device made it possible in particular to determine the minimum immersion depth allowing the sargassum algae to achieve negative buoyancy in water (relative density greater than 1).

[0012] TECHNICAL MEANS FOR IMMERSION OF ALGAE

[0013] Sargassum seaweed immersion techniques can be carried out using different processes:

[0014] Solution 1): Immersion by pumping

[0015] A mixture of sargassum and sea water is pumped directly to the surface. This mixture is sent, through a discharge pipe, to the necessary depth allowing the sargassum to have a relative density greater than 1. Once released from the discharge pipe, the sargassum will complete its immersion by gravity.

[0016] [Fig.l] shows a schematic diagram of this solution.

[0017] In order to artificially increase the pressure inside the discharge pipe, it would be possible to add a pressure loss device to the end of the latter. This modification will lead to an increase in the pressure in the pipe, as well as the phenomena of degassing of the algae, and therefore a complementary loss of their buoyancy at the outlet of the discharge pipe. This device allows a shortening of the discharge pipe compared to the theoretical minimum immersion depth.

[0018] This technical solution of immersion by pumping is the simplest to implement of the three techniques presented in this document. It can be deployed from small floating units, such as fishing boats. The sargassum removal strategy can thus be supported by numerous floating units with limited equipment costs and maintenance charges.

[0019] Solution 2): Immersion by chimney

[0020] The treatment vessel (boat or barge) collects the sargassum present on the surface and transports it (via a conveyor belt for example, or pumping, or any other system) to an immersion chimney. This chimney is supplied with seawater by a pumping system which will load the water column in the chimney and cause a vertical flow descending into it. This chimney is of sufficient length to reach the depth beyond which the sargassum will complete its immersion by gravity.

[0021] The water extraction for pumping could be carried out at a great depth, allowing water at a colder temperature than that present at the surface to be added to the top of the chimney, and which therefore has a higher density than the warmer surface water. This difference in density creates a downward current. The downward circulation of water allows the sargassum to be carried to the bottom.

[0022] [Fig.2] shows a schematic diagram of this solution.

[0023] Solution 3): Immersion by “elevator”

[0024] Immersion by "elevator" is carried out through a three-step sequence

[0025] -Step: the sargassum is gathered and contained in a surface enclosure (for example a trap, a net, a box, a container, etc.). This enclosure is called here an "elevator" for convenience.

[0026] -Step 2: the elevator is brought to the desired depth by any system (ballast, cables connected to floats or surface vessel, buoys, propellers, etc.). The elevator allows the sargassum to be transported during immersion.

[0027] -Step 3: Once the desired depth is reached, the elevator releases or abandons the sargassum so that it can complete its immersion by gravity. The elevator is then brought back to the surface and can resume a collection and immersion cycle.

[0028] [Fig.3] shows a schematic diagram of this solution.

Claims

Claims

1. Method for eliminating sargassum seaweed in a coastal area characterized by the principle of pressurizing said seaweed, allowing degassing and a reduction in the density of its tissues until they have a relative value greater than 1, then making it possible to cancel the buoyancy of the seaweed and allow its deep and definitive immersion in the sea by simple gravity.

2. Method according to claim (1), characterized by the implementation of a forced immersion deep into the sea of ​​the sargassum algae, by different hydraulic or mechanized techniques, with the objective of reaching the pressure necessary to give it a relative density greater than 1, thus making it possible to cancel the buoyancy of the algae and to allow its deep and definitive immersion in the sea by simple gravity.

3. Method according to claim (2), characterized by the implementation of pumping a mixture of water and sargassum algae to the surface, and a discharge pipe allowing the mixture to be discharged at a sufficient depth to give it a relative density greater than 1, thus making it possible to cancel the buoyancy of the algae and to allow its deep and definitive immersion in the sea by simple gravity.

4. Method according to claim (3), characterized by the implementation of a voluntary over-pressurization of the pumping discharge pipe, thus making it possible to reach more quickly (i.e. with a shorter pipe) the depth and therefore the pressure necessary to give the algae a relative density greater than 1, cancel its buoyancy, and thus allow its deep and definitive immersion in the sea by simple gravity.

5. Method according to claim (2), characterized by the implementation of a vertical chimney in which a downward hydraulic flow is generated by hydraulic pressure by pumping sea water, and in which the sargassum algae is injected and transported to a sufficient depth until it gives a relative density greater than 1, then making it possible to cancel its buoyancy and allow its deep and definitive immersion in the sea by simple gravity.

6. Method according to claim (2), characterized by the implementation of an "elevator" making it possible to mechanically contain sargassum algae, transport them to a sufficient depth until they give them a relative density greater than 1, and then release them to allow their deep and definitive immersion in the sea by simple gravity

Images