VERTICAL LIFT STUDY FOR HARVESTING OF SEABED MINERALS FOR DEEP SEA MINING

Abstract

The vertical lift technology is one of the four main areas of study in the process of harvesting of seabed minerals from a depth of 4500m below the ocean to the surface. In this thesis, a brief overview of the full scale process will be described and some conceptual ideas for the vertical lift technology will be discussed, among which, one of them will be the focus of the study, namely lifting the nodules in a riser via a hydraulic method. After which, an experimental study of the flow of nodules in a vertical pipe will be explored. The minimum lift conditions such as minimum flowrate, time taken for transportation of nodules as well as the interaction of the nodules with the flow stream will be investigated in detail and the implications of this on the system will be explored. Furthermore, we will look into the drag coefficients involved in the transportation firstly for a single nodule, and then for a swarm of nodules. The experimentally obtained data will then be validated with known theoretical models. We will then evaluate what are the implications of the experimental findings on the real life scenario.