Abstract: 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.

Abstract: The invention relates to a seabed foundation (1) for an offshore facility, comprising a primary pressure chamber (7) connected to a primary pump (8) and one or more secondary pressure chambers (9) connected to one or more secondary pumps (10). According to an embodiment of the invention, said primary pump is a suction pump and said secondary pump is a pressure pump. The invention further relates to a method (12) of installing said foundation on the seabed (19), which comprises the steps of activating (14) said primary pump to create negative pressure in the primary pressure chamber (7), so that the foundation sinks into the seabed, and activating (15) said one or more secondary pumps (10) to create positive pressures in the secondary pressure chambers (9), so as to control the alignment of the foundation with respect to a substantially horizontal axis (16) during the sinking into the seabed.

Abstract: A fluidified inert material spreading device configured to bury a pipeline in a body of water is configured to travel in the body of water in a travelling direction along and over the pipeline, and has a hull, which extends along a longitudinal axis, houses at least one expansion chamber for fluidified inert material, is connected to at least one feed port to feed the fluidified inert material to the expansion chamber, and has a quantity or number of outlet ports configured to release the fluidified inert material from the expansion chamber, close to the pipeline, and which as a whole define a flow cross section greater than the flow cross section of the feed port.

Abstract: A method and apparatus for selectively removing fine sediments from a water body bottom using a dredging head with one or more intake openings situated to accelerate flows through the interior of the head and across the water body bottom causing fine particles to become suspended in a slurry outflowing from the head for disposal, while coarser, heavier, bottom gravels remain in place. The stream cleaner dredging head includes a main body having at least one intake, at least one plate attachment feature, a discharge point, and an at least partly open bottom; a flow-adjusting plate that is adjustably connected to the at least one plate attachment feature and configured to adjust a fluid flow through the main body from the at least one intake, and a hose attachment connected to the discharge point of the main body.

Abstract: A dredging apparatus is described for removing sediments from a bed of an expanse of water, comprising: a suction apparatus including a) a submersible pump including: a housing body provided with an inlet mouth and with a discharge opening and an impeller rotatably supported in the body between the inlet mouth and the discharge opening and rotatably driven by a respective driving device; and b) a suction head associated to the inlet mouth of the housing body of the pump and provided at the bottom with a suction opening of the sediments; wherein the suction opening of the head has a value of the cross-section area dimensioned to achieve in the working range of the pump a suction speed capable of removing the sediments by means of the fluid dynamics removal action carried out by the water sucked into the head. The invention also describes a dredging method which may be carried out by means of such an apparatus.

Abstract: A drag head of a trailing suction hopper dredger. The drag head comprises a rotatable visor connected to a suction pipe for discharging soil via the suction opening of the visor, wherein the visor is provided with a catching construction for undesirable objects. The catching construction closes the suction opening except for passage openings, wherein at least a number of passage openings have a variable passage area. A method for breaking up and/or dredging at least partially hard grounds under water using a trailing suction hopper dredger equipped with a drag head.

Abstract: There is disclosed an underwater excavation apparatus (5) comprising: means (10) for disturbing or excavating an underwater location, comprising mass flow excavation means (20); and means (15) for extracting or sucking excavated material from the location to another location comprising further mass flow means (25). Means (30) to restrict spoil and/or direct spoil to the suction means (25) are provided and comprises a baffle (35) provided within a cavity (45) of a housing (40) having an open base (60). An outlet (105) of the mass flow means (20) and an inlet (110) of the suction means (25) are located within the housing (40), while an inlet (100) of the mass flow means (20) and an outlet (115) of the suction means (25) are located external of the housing (40).

Abstract: The sludge treatment system is comprised of a dam passage penetrated through a dam (D); an induction pipe (11) for discharging a sediment retained by the dam (D) and having an inlet (11a) toward the floor of the dam (D) and an outlet connected to an inner end of the dam passage; an induction force action pipe (13) connected to an outer end of the dam passage and extended in a height for utilizing an atmospheric pressure as an induction force of the sediment; a U shape air control pipe (14) connected to the induction force action pipe (13), and preventing for an air from coming into the induction force action pipe (13); a drain pipe (15) connected to the air control pipe (14) for discharging the sediment; and an air vent pipe (16) connected to a horizontal flat portion of the air control pipe (14) for dissipating the induction action of both the air control pipe (14) and the drain pipe (15).

Abstract: A drag head of a trailing suction hopper dredger. The drag head comprises a rotatable visor connected to a suction pipe for discharging soil via the suction opening of the visor, wherein the visor is provided with a catching construction for undesirable objects. The catching construction closes the suction opening except for passage openings, wherein at least a number of passage openings have a variable passage area. A method for breaking up and/or dredging at least partially hard grounds under water using a trailing suction hopper dredger equipped with a drag head.

Abstract: Contaminated fine sediment is removed from surfaces beneath a body of water by a shrouded, self-cleaning, wheel-guided, open suction attachment for a swinging ladder suction dredge with articulating capabilities. The attachment comprises a wheel-guided, suction assembly in which the slurry is contained in a shroud. The shroud is attached to a head plate, and is designed to both enclose the solid particles suspended as a result of the removal operation, and to direct the suspended material to the mouth of the suction pipe. Inside the area surrounded by the shroud is a gatling plate rotated by a hydraulic motor mounted just above the shroud and head plate.

Abstract: Dredge heads, for use with a dredging system, include one or more movable members, e.g. grate members, adapted and configured to selectively extend across the opening of the dredge head. The movable member(s) enables a user to clear the dredge head of plugging masses or blockages without having to de-energize the dredge system pump. Also, the movable member(s) enable a user to clear the dredge head of plugging masses or blockages without requiring the user to manually, by using his or her hand, withdraw the plugging masses or blockages from the opening of the suction/dredge heads.

Abstract: A vacuum truck solids handling apparatus includes a truck having an internal combustion engine and a truck frame. A vacuum source, a solids collection container and a separator assembly are all mounted on the truck frame. The separator assembly is adapted to separate solids from a fluid stream drawn under vacuum by the vacuum source. The separator assembly has a pivotally mounted discharge, which pivots between a closed discharge position and an open discharge position. In the closed discharge position, the discharge discharges solids into the solids collection container. In the open discharge position, the discharge discharges solids externally.

Abstract: A tool for excavating an object comprises a jetting system having a nozzle arranged to receive a fluid and abrasive particles via an abrasive particle inlet, and arranged to impinge the object to be excavated with a jetted stream of the fluid mixed with the abrasive particles, the tool further having a recirculation system arranged to recirculate at least some of the abrasive particles from a return stream, downstream of the impingement of the jetted stream with the object to be excavated, back to the jetting system via the abrasive particle inlet, the abrasive particle inlet having an entrance window in which a device in a path fluidly connecting the return stream with the entrance window keeps the abrasive particle inlet free from objects of the same size or larger than the size of the window while allowing passage of the abrasive particles.

Abstract: A non-motorized apparatus for collecting particulate materials, including gold, in stream placer deposits, comprising a first tubular member, a second tubular member, a third tubular member with perforated ridges, a skirt for enveloping the tubular members, and a fibrous matting disposed over the third tubular member. The third tubular member with the fibrous matting is held entirely inside the second tubular member. The second tubular member is connected to one end of the first tubular member in a way to have high velocity stream flowing into the first tubular member, creating a suction pressure in the second tubular member. The particulate matter settles in grooves formed by the ridges in the third tubular member and passes through the perforations to be trapped in the fibrous matting as the stream is sucked into the second tubular member.

Abstract: A sludge removal apparatus includes a sludge removal head (10) with a sludge suction duct and an water supply duct with open end portions alongside each other, and a filter (32) adjacent to the open ends of the suction duct (36) and the water supply duct (38) so that the sludge is extracted through the filter (32). A drive mechanism moves the filter so that regions of the filter pass successively over the open ends of the suction duct, where it may become partially blinded with sludge, and then over the water supply duct where it is backwashed.

Abstract: An intake conduit apparatus comprises an intake conduit adapted at a downstream output end thereof for connection to an intake of a vacuum conveyor, and adapted at an upstream input end thereof to facilitate entry of granular material. Ramps slope inward and downstream from the interior wall of the intake conduit, and there is a vent hole through the wall of the intake conduit adjacent to a downstream end of each ramp such that air enters the intake conduit adjacent to the downstream end of each ramp.

Abstract: An excavation system comprises a bucket, defining an outlet at its base, in fluid communication with a suction tube in fluid communication with a jet pump, configured to create a suction in the suction tube. A related method of excavating comprises loading excavation material into a bucket which defines an outlet at its base, sizing the excavation material by sieving action of a guard substantially covering the bucket outlet, and suctioning the sized material though the bucket outlet using a vacuum created by a jet pump.

Abstract: A method and apparatus for remediating wastewater holding areas and the like includes a closed, foraminous dewatering membrane that is positioned adjacent to the wastewater holding area. Sludge and adjacent water on the bottom of the wastewater holding area are pumped in the form of a sludge slurry into the interior of the dewatering membrane. The water is removed from the sludge slurry by allowing gravitational forces to flow water through the dewatering membrane. The dewatering membrane is then opened, and the dewatered sludge is removed for depositing at an appropriate site.

Abstract: A method is described for removing sediments during dredging operations to minimize the release of contaminants at marine locations containing sediments that are deemed contaminated and require removal. The preferred method comprises the use of a specially designed marine vessel that establishes a negative differential pressure gradient between a dredge control zone and the external ambient water environment, thereby preventing the release of contaminants dispersed during the dredge process into the ambient water environment. The preferred method also includes the use of marine vessels to remove contaminants contained within said control zone and to provide for the management of solids collected in the process.

Abstract: A system and method removes contaminated sediments during dredging operations to minimize the dispersion of particulate matter that normally occurs during conventional mechanical or hydraulic dredging operations. The system uses a specially designed pressure controlled enclosure or enclosed excavator that houses a mechanical bucket. The enclosure is designed to capture suspended particles that are dispersed into the water column during the mechanical dredging process. The system also includes the use of a self-contained membrane filtration treatment vessel to remove fine particulate matter from dredge drainage waters collected in the process.

Abstract: A screening device including a screen having a first side for presentation to material to be screened and a second side, a plurality of screen openings in the screen extending between the first and second side thereof, a plurality of tines mounted on a support device disposed on the second side of the screen, each tine being moveable in a first direction along a path at least part of which includes one of the screen openings whereby the tine is receivable in and moveable along the screen opening, the tine extending beyond the first side of the screen for at least part of the movement thereof along the screen opening, the tines being moveably mounted on the support device for deflection away from said first direction while continuing to move in said first direction upon encountering an obstruction.

Abstract: A placer gold separating method includes subjecting placer gold-and gold ore-containing sand and gravel layers accumulated on the bottom of the water of a river and placer gold- and gold ore-containing sand and gravel layers formed deep in the ground to excavation or suction excavation by utilizing a water pressure difference. This causes a mixture of the excavated or suction excavation placer gold- and gold ore-containing sand, gravel and water to flow horizontally by the action of a pressure fluid. The placer gold and gold ores are separated by utilizing a specific gravity difference while the mixture is flowing. A placer gold mining boat used to practice this method is provided thereon with a combination of a suction excavation component, a mixture transfer component, a component for separating placer gold by utilizing a specific gravity difference, and a component for discarding the remaining mixture from which the placer gold has been separated.

Abstract: A screening device including a screen includes a first side for presentation to a body of material to be screened and a second side. A plurality of elongate screen openings are formed in the screen extending between the first and second sides thereof. A plurality of tines mounted on support means disposed on the second side of the screen. Each tine is movable along a cyclical path at least part of which includes one of the elongate screen openings whereby the tine is receivable in and movable along the elongate screen opening. The tine extends beyond the first side of the screen for at least part of the movement thereof along the screen opening. The screening device may be incorporated in various machines including a recovery head for an underground mining apparatus.

Abstract: The present invention pertains to debris exclusion devices designed for use on a small augerhead type hydraulic dredge system for operations in debris laden channels that can cause the system's pump to malfunction. Debris to be excluded by these devices include portions of trees, woody-stemmed plants, pieces of lumber, pieces of metal or even unexploded ordinance. A first embodiment comprises vertical grates with curved front surfaces mounted in front of a spoils inlet of a dredgehead shroud with cooperating cutter assembly attached to the auger. These grates are spaced to allow passage of spoils and small debris, but not larger injurious debris that is detrimental to the system's pump. A second embodiment is a tapered transition box device attached to the augerhead's shroud disposed between the grates of a spoils inlet leading through these grates and a hose feeding the system's pump. The box is a clean-out device which is self-regulated and also maintains smooth transitional flow to the system's pump.

Abstract: A method of hydraulic dredging employing apparatus and a procedure for subsidence dredging for subsurface removal of sandy strata which results in subsidence, or drop in elevation of the bottom deposits of a body of water, wherein sand is mined laterally beneath the surface by a combination jetting/siphoning device and is transported from the site of dredging by pipeline apparatus connected to pumping apparatus to an adjacent beach location; and wherein the procedure employs removal of hydraulic pressure which results in subsidence or sinking of the upper layer of marine deposits where the amount of subsidence is directly related to the subsurface quantity of material removed and the removed material is used for beach nourishment with minimal damage to shellfish or finfish inasmuch as the surface beneath the deposits are left intact.