Described are a vessel and vessel/barge systems for dredging underwater surfaces. The vessel includes a hull with a bottom, bow portion, stern portion, port side, and starboard side. The vessel also includes a deck supported by the hull and a pump system mounted within the hull. A drag arm pivotably couples to the pump system. The vessel additionally includes a void defined by contiguous watertight walls or bulkheads joined to and extending upward from the bottom of the hull. The contiguous watertight walls or bulkheads are (i) vertically extensive of a perimeters of an aperture in the bottom of the hull, (ii) outboard, astern, and forward the aperture, or (iii) some combination thereof. The barge is releasably coupled to the vessel. Moreover, the barge is in fluidic communication with the drag arm.

A dredge head assembly is disclosed. The assembly includes: a shroud having a generally open bottom end and a top end; a screen structure covering the generally open bottom end of the shroud; a suction pipe with a first end connected to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction; a handle connected to and extending from the shroud and having at least one grasping portion; and one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver. Dredging systems and methods of dredging are also disclosed.

The present application discloses a dredging system for a pre-paved gravel foundation bed surface in open sea deep water, including a dredging mechanism, which includes a dredging suction head, a power component and a dredging pipeline, wherein the dredging suction head is connected with the dredging pipeline; the dredging pipeline is communicated with the power component; the dredging suction head includes at least one ridge surface suction port and at least one furrow suction port; the openings of all the furrow suction ports are lower than those of all the ridge surface suction ports; a lifting mechanism, which is connected with the dredging suction head and is used for lifting the dredging suction head to the gravel foundation bed surface; a moving mechanism, which is connected with the lifting mechanism and is used for driving the dredging suction head to move within a dredging range of the gravel foundation bed surface. By the adoption of the dredging system for the pre-paved gravel foundation bed surface in the open sea deep water of the present application, the dredging suction head includes the ridge surface suction ports and the furrow suction ports, and may suck mud on the top surfaces of gravel ridges and the mud in furrows between two gravel ridges at the same time, thereby guaranteeing the dredging quality of the gravel foundation bed surface and improving the working efficiency. The dredging system is simple in structure, convenient to use and good in dredging effect.

A piece of submarine mining equipment comprises an equipment body, a plurality of adaptive submarine mining collectors and respective mineral delivery pipes. The equipment body and the adaptive submarine mining collectors are connected through the mineral delivery pipes. The lengths, stretching out of the equipment body, of the mineral delivery pipes can be adjusted under control. The adaptive submarine mining collectors are provided with tracked traveling mechanisms and can autonomously travel under control. An underwater detector is used for detecting the submarine topography and mineral distribution in the vicinity of an operation area, and the traveling path of the submarine mining collectors and a mineral storage vehicle is reasonably planned according to detected information. The multiple adaptive submarine mining collectors simultaneously and independently work and are made light and small, thus reducing damage of mining operations to the submarine ecological environment. The equipment body can travel along flat submarine paths and avoid rough paths. Horizontal vortexes induced by the mining collectors can enhance the mining effect and improve the collecting power under unit power consumption so that fewer water pumps with smaller sizes can be configured, and the mining collectors have a smaller principle dimension, thereby greatly reducing energy consumption and being more environmentally friendly.

The liquid pump includes an inner and an outer tube. The inner tube can have a distal end that is position within interior volume of the outer tube. A conical filter is on the distal end of the inner tube. A gas pump provides compressed air which is output through a plurality of inner tube holes on an inner surface of the inner tube on a distal portion of the inner tube and a plurality of annular space holes which are adjacent to an annular space between the inner tube and the outer tube.

Described are a vessel and vessel/barge systems for dredging underwater surfaces. The vessel includes a hull with a bottom, bow portion, stern portion, port side, and starboard side. The vessel also includes a deck supported by the hull and a pump system mounted within the hull. A drag arm pivotably couples to the pump system. The vessel additionally includes a void defined by contiguous watertight walls or bulkheads joined to and extending upward from the bottom of the hull. The contiguous watertight walls or bulkheads are (i) vertically extensive of a perimeters of an aperture in the bottom of the hull, (ii) outboard, astern, and forward the aperture, or (iii) some combination thereof. The barge is releasably coupled to the vessel. Moreover, the barge is in fluidic communication with the drag arm.

Device for removing alluvial deposits (24) from the bed (29) of a body of water, whereby the device (1) consists of a bell (2) with an open bottom (3), whereby this device (2) is provided with means to control the water level (30) in the bell (2) and with suction means to suck up alluvial deposits (24), whereby a section of the sidewall (8) of the bell (2) is open at the bottom, whereby the opening (10) can be closed by a partition (12) that can be moved between a raised and a lowered position, and that the device (1) is provided with a drive (13) to be able to drive the partition (12) into the alluvial deposits (24).

There is disclosed an excavation apparatus (5), such as an underwater excavation apparatus, having means for producing, in use, at least one vortex, spiral or turbulent flow in a laminar flow of fluid, e.g. water. The excavation apparatus (5) comprises a rotor (10) having a rotor rotation axis (A), wherein, in use, flow of fluid past or across the rotor (10) is at a first angle (?) from the axis of rotation (A). The excavation apparatus (5) comprises the rotor (5) and means or an arrangement for dampening reactive torque on the apparatus (5) caused by rotation of the rotor (10), in use. The turbulent flow is provided within, such as within a (transverse) cross-section, of the laminar flow.

The invention relates to a cutter head for removing a mixture comprising water and solid materials from a water bottom, comprising rotating blades each provided with cutting means on a leading edge thereof, said cutter head being rotatably coupled to a tube for transporting said mixture, the shape of the leading edge of said rotating blades being defined by substantially fitting a rounded cone with a rotation axis, wherein each rotating blade at a middle part is coupled to a connecting ring and at a top part is linked to a top part of another rotating blade. The cutter head is characterized in that the rotation axis of said blades is substantially aligned with a rotation axis of said ring; in that a trailing edge of part at least one of said blades is positioned closer to said rotation axis than a leading edge of said blades so as to provide a suction function towards said tube upon rotation of said cutter head; and in that said blades as viewed from said top part at a bottom part of said blades extend to a position beyond said connecting ring. A preferred embodiment comprises a method for using the cutter head according to the invention.

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