Microdredging systems comprising a pumping platform and loading platform are described. In certain embodiments, system operates autonomously and is adapted to allow the loading platform undock from the pumping platform for disposal of the removed sediment.

A vehicle and method of use in subsea operations related to crushing concrete mattresses including at least one lift assembly, at least one crushing roller, at least one blow out pipe cable of blowing crushed concrete mattress fragments into a rubble container. In a preferred embodiment, the vehicle has at least one fork lift connected to the lift assembly, a digger chain assembly arrangement, treads, an interface connected to the vehicle and capable of engaging the rubble container, and each rubble container is detachable from the interface.

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 deep sea mining method includes providing a deep sea mining system for mining matter from a bottom of a body of water, the mining system including: a slurry line coupled with a pump system to transport the slurry from the bottom of the body of water; and a return line in fluid communication with the slurry line and distinguishable from the slurry riser, for transporting non valuable slurry part to the bottom of the body of water, the return line having a return line outlet proximate the bottom. The deep sea mining method further includes spreading the non valuable slurry part over the bottom of the body of water in a controlled manner.

A system and method of off shore mining for retrieval and extraction of heavy mineral concentrate from placer deposits or other suitable materials. The system comprises a dredge vessel and a barge, coupled in conjunction to the dredge vessel. The dredge vessel having thereon a dredging unit, at least one gravity separator and spiral separators for procurement of total heavy minerals from dredged sediment and debris. The barge is configured to acquire and process the total heavy minerals, wherein the barge has thereon at least one magnetic separator, electro-magnetic separators, and density separators for separation of desired minerals based on their physical properties. The system further comprises at least one discharge conduit for tailing of wastes, leftover after extraction and separation of desired minerals, back into water bodies.

A method of forming a structure includes a) excavating a material; b) homogenizing the material; c) ensuring aluminosilicate levels in the material; d) increasing alkaline levels of the material; e) foaming the material; and f) injecting the material onto a surface, wherein the material forms into a foam-like structure when injected.

An overflow system for a hopper dredger includes an overflow tube; and a plurality of canals adjacent and substantially parallel to the overflow tube. The plurality of canals have inlets at different heights for taking in head water from the hopper. The plurality of canals fluidly connect to the overflow tube at a point downstream from the inlets.

The present invention relates to a system for collecting, lifting, and recovering seabed mineral resources, specifically, a device wherein hydrogen gas is evolved on the seabed, resources are lifted by the buoyancy of the gas to the sea surface, and the hydrogen gas which has become an excess buoyancy source during the lifting and recovering is absorbed into an organic substance including toluene, thereby yielding hydrogenated compounds including cyclomethylhexane to recover the energy required for hydrogen gas production.

A system and method of off shore mining for retrieval and extraction of heavy mineral concentrate from placer deposits or other suitable materials. The system comprises a dredge vessel and a barge, coupled in conjunction to the dredge vessel. The dredge vessel having thereon a dredging unit, at least one gravity separator and spiral separators for procurement of total heavy minerals from dredged sediment and debris. The barge is configured to acquire and process the total heavy minerals, wherein the barge has thereon at least one magnetic separator, electro-magnetic separators, and density separators for separation of desired minerals based on their physical properties. The system further comprises at least one discharge conduit for tailing of wastes, leftover after extraction and separation of desired minerals, back into water bodies.

Systems and methods include a wing tool configured to be operable from work vessel(s), the wing tool including thrusters capable of fluidizing sediments from a first seabed location and moving it to a second seabed location, the second seabed location including a trench or differently shaped collection sump previously made by the wing tool and/or an extraction pump. The extraction pump operates from a second work vessel having sufficient capacity to pump fluidized sediments from the trench. Certain systems include a separation unit that separates sand from silts and clays and water from collected sediment. Systems and methods for reclamation of reservoirs, moving sand waves, for pre-trenching and/or recovering marine pipelines and cables, for removing cover from marine archaeological sites and for disposing of contaminated bottom materials in an environmentally acceptable manner.