Comminution of Polymetallic Nodules with a High-Pressure Water Jet

This paper presents an original method for the comminution of polymetallic nodules in a hydro-jet mill of our own design, having the water jet pressure in the range of 70-200 MPa. The best comminution results are ensured by equipping the mill with a water jet having a diameter d(w) = 0.7 mm and a comminution-homogenization tube having a diameter d(h) = 2.4 mm, and by setting a distance s = 10 mm from the outlet of the homogenization tube to the comminuting disc. Particles of concretions comminuted under such conditions are characterized by a fairly regular isometric shape and favorable morphology represented by intense development of the specific surface.