Patent ID: 7950463

Claim:
A method for removing submerged items from the seabed or from great sea depths, the method comprising: positioning a platform or a vessel above an offshore location; extending a riser from the vessel or platform so as to position the lower end of the riser at a selected subsea depth, said riser being vented to the atmosphere, said lower end being open to seawater surrounding said lower end, said riser being configured with an outlet at a level below the water surface, said outlet connected to a pump system having a return line running to a selected location; sucking said submerged items suspended in a fluid with an inflow of said fluid into the open lower end of said riser to the outlet, said fluid being mainly sea water drawn from a region external to but proximal to said open lower end of said riser; and removing said particles and fluid from the riser via the outlet and return line to the selected location while keeping the level of the fluid in the riser at a level between the outlet and the sea surface corresponding with a selected pressure in the lower end of the riser substantially lower than the sea water pressure at the lower end of the riser by use of the pump system.