Archimedes Plasma Mass Filter

The Archimedes’ Plasma Mass Filter is a novel plasma‐based mass separation device. The basic physics of the Filter concept and a description of its primary application for nuclear waste separation at Hanford will be presented along with initial experimental results from a Demo device. The Demo is a 3.89 m long cylindrical device with a plasma radius of 0.4 m and an axial magnetic field up to 1600 Gauss. The plasma is produced by helicon waves launched by two four‐strap antennas placed symmetrically either side of a central source region. One strap of each antenna is powered by one of four phase controlled 1 MW transmitters operating in the frequency range from 3.9 – 26 MHz. Each end of the device has ten concentric ring electrodes used to apply an electric field to rotate the plasma. Application of a parabolic voltage profile results in a rigid body rotation. Heavy ions above the cut‐off mass number are extracted radially and collected by a heavy ion collector surrounding the source injection region while light ions are collected at the ends of the cylinder. Initial experiments will use noble gas and trace metals to demonstrate separation before attempting to operate with complex waste characteristic of Hanford.