Effect of particle motion on the hydraulic collection of coarse spherical particles

Deep-sea mining,through which shattered coarse solid mineral resources are hydraulically collected and transported,is a promising solution for problems associated with resource exhaustion.This study reports some interesting phenomena observed in a series of upward pumping experiments conducted on a coarse sphere with a 2-cm radius.The sphere was hydraulically lifted using a vertical pipe with a 5-cm radius suspended above the sphere.Remarkably,the tangential motion benefited the collection.The discrete element method-computational fluid dynamics was used to investigate the collection mechanism;this method was used to simulate the collecting processes of the sphere under different initial motion conditions.The simulated results agreed well with the experimental observations.The vortices over the sphere induced by its motion coupled with the main stream mainly provide sufficient lift force to raise the sphere.