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.

The invention relates to a method for ground-working at a bottom of a body of water and a cleaning device for cleaning an underwater ground-working apparatus. The cleaning device has an enclosing body which extends substantially from a bottom of a body of water to above the water surface and enclosing an inner space, along which the ground-working apparatus can be moved, and a separating device, through which in the enclosing body an upper portion of the inner space can be separated off to form a cleaning area, in which the ground-working apparatus can be received and soil and contamination cleaned from it.

The invention relates to a method for ground-working at a bottom of a body of water and a cleaning device for cleaning an underwater ground-working apparatus. The cleaning device has an enclosing body which extends substantially from a bottom of a body of water to above the water surface and enclosing an inner space, along which the ground-working apparatus can be moved, and a separating device, through which in the enclosing body an upper portion of the inner space can be separated off to form a cleaning area, in which the ground-working apparatus can be received and soil and contamination cleaned from it.

A hydrovac having a chassis, a mud tank and water tank assembly mounted on the chassis, a hydraulic lift assembly capable of raising the mud tank and water tank assembly through a dump angle, the mud tank having a floor, and the floor of the mud tank deepens forwardly. A belt drive is provided for a blower of the hydrovac, along with belt tensioning system.

A hydrovac having a chassis, a mud tank and water tank assembly mounted on the chassis, a hydraulic lift assembly capable of raising the mud tank and water tank assembly through a dump angle, the mud tank having a floor, and the floor of the mud tank deepens forwardly. A belt drive is provided for a blower of the hydrovac, along with belt tensioning system.

The invention relates to a diaphragm wall cutter for cutting a cutting trench in the ground, comprising a cutting frame, at least one rotatably drivable cutting wheel which is mounted on an lower side of the cutting frame, a suction nozzle, which is arranged in the region of the at least one cutting wheel and is provided with at least one suction opening, and a suction pump which is configured for suctioning slurry from the cutting trench during cutting via the suction nozzle, the suction pump being connected to the suction nozzle via a suction line. According to the invention, it is provided that at least one filling port is provided for filling the suction pump and the suction line with a liquid when the suction line is shut-off, wherein the suction line and the suction pump are filled with liquid for starting the suction pump.

A pneumatic excavator is configured to be pneumatically actuated using a safety mechanism, and includes a primary actuator; a secondary actuator fluidly coupled to the primary actuator; a flow valve fluidly coupled to the primary actuator; a shuttle valve fluidly coupled to the primary actuator, the secondary actuator and the flow valve; and a barrel coupled to an egress of the flow valve, the barrel defining an outlet of the pneumatic excavator. Actuating the primary and secondary actuators causes compressed air to be transmitted from the secondary actuator to the primary actuator and then to the flow valve to open the flow valve such that the compressed air exits through the outlet. Actuating one actuator and not the other causes the compressed air to be transmitted to the exit port of the shuttle valve and then to the flow valve to close the flow valve and prevent air flow therethrough.

A pneumatic excavator for delivering pulsed compressed air includes an actuator; a controller valve; a flow valve; a barrel defining an outlet of the excavator; and a pulse control line extending between the controller valve and a port downstream from an egress of the flow valve. As compressed air flows through the egress of the flow valve, the pulse control line is pressurized and shifts the controller valve to an actuated position, causing the compressed air from the actuator to close the flow valve, thus preventing the air flow from passing through a primary flow passage and through the outlet. The pulse control line being no longer pressurized by the air flow, then causes the controller valve to move to an unactuated position to cause compressed air from the actuator open the flow valve and permit the air flow through the outlet and again pressurize the pulse control line.

A pneumatic excavator configured to be pneumatically actuated includes an actuator; a flow valve fluidly coupled to the actuator an air actuation conduit; and a barrel coupled to an egress of the flow valve, where the barrel defines an outlet of the pneumatic excavator. Actuating the actuator causes compressed air to be transmitted from the actuator through the an air actuation conduit to a first port of the flow valve to open the flow valve and compressed air from a supply of compressed air passes through the flow valve and the outlet of the pneumatic excavator. Releasing the actuator causes the compressed air to be transmitted from the actuator through the at least one air actuation conduit to a second port of the flow valve to cause the flow valve to close and the flow valve prevents the compressed air from the supply of compressed air from passing therethrough.

An aero-excavation apparatus for collecting a fractured soil material using a vacuum hose, the apparatus comprising: a main frame; a motor mounted on the main frame; a traction and direction system in driving arrangement with the motor for driving and operating the main frame; and a blower in driving engagement with the motor; wherein the blower is in fluid communication with the vacuum hose for collecting the fractured soil material.