Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
th
, 2014
10135-200-46 - Rev. 0
24-2
24.3 Process Description
Conceptual process flow diagrams were developed that could be used to recover the
by-products that have been identified. These processes would need to be validated
using bench scale and pilot scale studies
24.3.1 By-Product Recovery - Gold
Measureable amounts of gold exist in both the Bull Hill and Whitetail mineralization.
Gold could be recovered from the leach solution, right after the leach solution filter, by
means of a solvent extraction process. Gold is selectively extracted into the organic
phase using solvent extraction.
24.3.2 By-Product Recovery - Aluminum and Iron
Aluminum and Iron could be recovered as hydroxides by selective precipitation. The
solid residue recovered from the distillation column bottom is dissolved in water and
sent to the Al-Fe Neutralization reactor where the solution is neutralized to a pH of
approximately 3.5 using sodium carbonate. Sodium carbonate was chosen in this
design because it represents a significant cost savings over sodium hydroxide. The
Al and Fe hydroxide solids are then filtered and disposed of in the tailings storage
facility while the depleted solution is sent to the uranium recovery unit. If possible,
the Fe/Al hydroxide mixture can be sold or given away (as a mixed metal) to reduce
the amount of material going to the tailings unit.
24.3.3 By-Product Recovery - Uranium
Uranium could potentially be recovered through an ion exchange column containing
uranium specific resin. Uranium is not currently considered as a product because its
production would require additional licensing.
24.3.4 By-Product Recovery - Lead
Lead is separated from the main solution by selective precipitation using sodium
hydroxide. The precipitation is achieved in a neutralization reactor where the solution
is neutralized to a pH of 5.5. The solid precipitate is filtered and calcined to yield a
lead oxide product. The lead-free solution is sent to the zinc recovery unit.
