AN APPARATUS FOR ON-LINE DETECTION OF MAGNETIC RESONANCE SIGNALS FROM A TARGET MATERIAL IN A MINERAL SLURRY

摘要

An apparatus is provided for on-line detection of magnetic resonance signals from a target in a mineral slurry. The apparatus comprises (i) an electrically conductive housing, (ii) an electrically non-conducting (ENC) pipe to enable throughput of a mineral slurry and configured to pass through the electrically conductive housing, (iii) a first primary coil configured to encircle a section of the ENC pipe within the housing, the or each primary coil defining a measurement zone, (iv) a capacitor unit coupled to a terminal of the or each respective primary coil, where a value of each capacitor unit value is selectable so that a primary coil series resonance is formed close to the value of the magnetic resonance frequency of the target, (v) an RF transmitter operable to transmit a signal to one or more drive coil electrical networks, where an operating frequency of the RF transmitter is set approximately equal to the magnetic resonance frequency of the target, (vi) at least a first drive coil and an associated drive coil electrical network, where the number of drive coils equals the number of primary coils, and where each drive coil and associated drive coil electrical network is positioned relative to a single primary coil to magnetically couple said drive coil to said primary coil, (vii) an impedance monitor coupled to each drive coil electrical network and operable to measure a complex input impedance of said drive coil electrical network; and (viii) an RF receiver adapted to receive from the first or each drive coil electrical network, magnetic resonance signals from the target, the RF receiver forming an output signal of detected signals.