Abstract:
Current technologies for the detection and extraction of diamonds involve the repeti tive mechanical crushing of kimberlite ore, resulting in the damage of real diamonds.
In particular, the breakage of large diamonds into smaller constituents decreases
their value drastically, resulting in huge financial losses to mining companies. This
dissertation focuses on testing a newly developed technology for the detection of di amonds in the kimberlite ore prior to crushing processes, thus preventing breakage
and retaining their value. This technology is based on the tagged neutron method
which involves the irradiation of the ore by fast neutrons of 14.1 MeV and the detection of characteristic gamma rays from the inelastic scattering of neutrons. The
criterion for diamond detection is the presence of increased carbon concentration
within a certain area of the kimberlite sample.
This dissertation presents the results of the testing of the pilot prototype called
Diamant-1000 where the neutron source is a portable neutron generator with inbuilt
256 channel alpha-detector from gallium arsenide. The characteristic gamma-rays
are detected by a system of 22 bismuth germanium oxide detectors in coincidence
with signals from the alpha detector. The Diamant-1000 prototype was tested
on kimberlite ore from the Archangelsk mine in Russia and the Letseng mine in
Lesotho. Diamond imitators ranging from 8 to 20 mm are inserted in the kim berlite stones ranging from 30 to 150 mm, which are placed in trays and passed
through the neutron module. The minimum size of the diamond imitator detected
was 8 mm (5 carats). The prototype had a throughput of about 1 ton/hour (1060
kg/hr) with false alarms rate of 3%. The probability to detect diamonds hidden in
kimberlite ore of the range -150 + 100 mm is 95%, whereas for the kimberlite ore
within the range of -90 + 40 mm the probability is 97%. The electric consumption
of prototype is 0.6 kW/ ton of ore.
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The study demonstrates that the tagged neutron method has the potential to be
of significant benefit to mining industries in terms of profits, minimum waste and
minimal impact on the environment. This method is especially valuable for pre venting damages of large diamond
Motswakae, S (2024). Detection of diamonds using the tagged neutron method. Afribary. Retrieved from https://track.afribary.com/works/detection-of-diamonds-using-the-tagged-neutron-method
Motswakae, Sebele "Detection of diamonds using the tagged neutron method" Afribary. Afribary, 30 Mar. 2024, https://track.afribary.com/works/detection-of-diamonds-using-the-tagged-neutron-method. Accessed 24 Dec. 2024.
Motswakae, Sebele . "Detection of diamonds using the tagged neutron method". Afribary, Afribary, 30 Mar. 2024. Web. 24 Dec. 2024. < https://track.afribary.com/works/detection-of-diamonds-using-the-tagged-neutron-method >.
Motswakae, Sebele . "Detection of diamonds using the tagged neutron method" Afribary (2024). Accessed December 24, 2024. https://track.afribary.com/works/detection-of-diamonds-using-the-tagged-neutron-method