Ocean mining operations

TLDR: In this paper, the authors compared various methods of dredging, especially bucket dredging and suction dredging in the offshore mining field, and concluded that an overlaying horizontal layer of granular material, it is concluded, can best be removed using a trailing hopper dredger.

Abstract: The ever increasing size of bulk carriers of deeper draft requires dredging at ever increasing depths and distances from the coast. This article compares various methods of dredging, especially bucket dredging and suction dredging. In deep areas suction dredging is usually the preferred method. It is shown how a centrifugal pump system has about twice the economy of a venturi system. The article then discusses the application of dredging plants to offshore mining, considering the area to be mined and the type of mineral to be removed. An overlaying horizontal layer of granular material, it is concluded, can best be removed using a trailing hopper dredger. To penetrate the bottom to greater depths suction dredgers provide the best method. A cuttersuction unit is best for gradual excavation over a certain height and width.