The Uranium Ore Discriminator measures the gamma radiation emitted by a uranium ore truck load and establishes the average uranium ore grade on the truck so uranium ore could be stockpiled more accurately within the required uranium ore grade range.
The RDS uranium ore discriminator is based on the detection of the gamma radiation by two independent Gamma Detector Units (GDUs) situated approximately 1 – 1.3 m from both sides of the uranium ore truck tray. Each GDU contains 3 – 4 pairs of lead shielded gamma radiation detectors (GRDs) coupled with high voltage/amplifier boards. It has been estimated by computer modeling that the maximum error due to an incorrect parking of the truck is approximately +/- 6 %. Provided the truck with uranium ore parks closer to one GDU its higher gamma count is compensated for by the lower count of the second GDU that is situated further from the side of the truck tray.
The Discriminator Control Panel (DCP) can process the gamma count of up-to 4 left and 4 right pairs of GRDs in 10 s, 20 s or 30 s counting windows. The counts of the Left and Right GDUs (CL and CR respectively) are displayed separately on the bottom line of the DCP. The measured average U3O8 concentration is displayed on the top line and is calculated from the net left and right truck gamma count (the left GDU and the right GDU background counts are programmed into the DCP memory and are automatically subtracted from the total left GDU and the right GDU 'truck' signal counts).
The DCP and a PC in the control room communicate via a radio. When the truck stops between GDUs the truck driver reports by radio to the operator. The operator enters the truck number into the spread sheet and starts counting. When the count is finished the DCP reports the total count and the assessed ore grade to the PC. The operator directs the truck driver by the radio where the uranium ore load is to be dumped.
The discriminator has 10 programmable uranium ore grade cutoffs. The DCP and 2 GDUs are powered by a 12 V acid gel battery coupled with a solar panel.