Dredging Methods for Deep-Ocean Mineral Recovery

A great deal of interest has been generated in recent years in possible recovery of minerals from the marine environment. Mineral resources of the sea are listed and the most promising dredging methods are discussed. These include the suction dredging method and air-lift principle. When a pump is located on a ship or a floating platform the dredging depth may be extended to 600 ft by means of jet pumps in the suction line. When a dredge pump is located at the bottom, the dredging depth may be increased to 15,000 ft–18,000 ft, provided sufficient power is available. Equipment is being developed for specific purposes such as submersible dredge for beach nourishment projects, or an air-lift method for deep ocean mining. Need for research into the effects of shallow and deep ocean mining on the ecology and environment and need for international.