Systems and methods for recovering and concentrating rare earth elements from seabed sediment deposits using seabed excavators and shipboard processing systems.

A method for deep sea mining includes generating an upward flow of valuable matter in a riser line from the bottom of a body of water to a matter processing platform; processing the matter at the processing platform; generating a return flow in a return pipe of a mixture of seawater and a non-valuable part of the matter from the processing platform towards the bottom of the body of water; and controlling the pressure in the return pipe for avoiding collapse of the return pipe and/or cavitation of the return pipe, in particular for avoiding collapse of or cavitation in an upper part of the return pipe.

The invention relates to a sheet (1) to be placed in relation to a split barge (100) for encapsulating a bulk of material (101) to be dumped when the bulk of material is released, the sheet comprising a material containing portion (4) and at least one material free portion (3) extending from at least two opposed sides of the material containing portion, wherein that the immersed sheet encapsulating the bulk of material comprises an encapsulated body (20) encapsulated by the material containing (4) portion and a self-closing portion (22) being at least a part of the material free portion (3) both extending from an assembly point (21), wherein a closing length of the self-closing portion (22) correspond to at least 5% of the circumventing length of the encapsulated body (20), the circumventing length extending from the assembly point (21) to the assembly point (21). The invention further relates to a method of encapsulating a bulk of material by means of a sheet.

A system for seafloor mining comprising a vertical riser anchored to the seafloor; a mining machine to deliver seafloor ore to the vertical riser; a lifting system to pass the ore through the vertical riser; and a transport vessel removably connected to the vertical riser to receive ore from the vertical riser.

A seafloor haulage system (10), for lifting seafloor materials from the seafloor to the surface, that has a line member (150), preferably synthetic rope, that extends at least partially between the seafloor and the surface and a container (400), preferably a plurality of containers, capable of carrying a load connected to the line member (150). The containers have a steerable element (410), such as a rudder, that enables the container to manoeuvre as it is propelled, typically towed by the line member, through the water.

A floating filtering apparatus is used to separate solid material in a slurry by size, so that the filtered slurry and/or solid material that has been separated from the slurry can be further processed. The floating filtering apparatus comprises a filtering assembly, a first submergible tank, a first pump, and a receptacle for secondary material. The floating filtering system is contained in or supported by a vessel that floats on water and can move and/or be moved about on the surface of the water.

Marine pump vessels and wing fluidizer support vessels, and methods of using same. Wing fluidizer support vessels are configured to deploy a wing fluidizer including thrusters capable of fluidizing sediments from a first seabed location and moving it to a second seabed location. Pump vessels include one or more pumps deployable from a separate vessel and stowable thereon.