A superconducting magnet system for a very high intensity magnetic mineral separator

The basic cryogenic engineering requirements for building a superconducting magnet system for the magnetic separation of minerals are considered. The different construction problems for solenoids and non-circular coils are considered. The solution adopted is epoxy impregnation with high density glass-fibre inserted to control the difference in expansion coefficient between epoxy resins and the winding material of the superconducting magnet. The short hold-time cryostat required for preliminary measurements is described and proposals made for a small scale pilot plant machine with continuous refrigeration.