Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
th
, 2014
10135-200-46 - Rev. 0
13-25
concentrates were performed by SGS using pressure filters. Testing showed that by
using a pressure filter, all slurries could be filtered to produce a filter cake that is
below 15% moisture with the exception of Comp 1A (Bull Hill oxide ore). Comp 1A
showed borderline moisture content data as far as the prerequisite (demand) to meet
15%moisture target is concerned. In operations, Comp 1A (pure BH HG ox) will not
be processed alone for too long. Comp 1 A to will be blended with other ores that
filter well to achive an acceptable filter cake moisture. Note that Comp 4 filter cakes
all had moisture contents of around 30%. This is not an issue as there will never be a
need to store Comp 4 as a filter cake in a bin.
The data was found to be on borderline for White Tail but not good for Bull Hill
precon. Jenike and Johanson recommended keeping moisture below 15% to store
the pre-concentrate in a silo.
13.6.6 SGS – Hydromet Plant Testing
Process Flow Diagrams (PFDs) for the Hydromet Plant are found in Chapter 17,
Figures 17.10 to 17.30. These illustrate the process flows and the process
equipment in the Hydromet Plant.
13.6.6.1 Leach Testing
Using samples generated in the PUG pilot tests, Hydromet bench scale and pilot
testing were undertaken. Three major pilot testing campaigns took place. In the
initial campaign, co-current leaching was carried out at high temperature. Testing
was also carried out to optimize the leach temperature and the concentration of
hydrochloric acid used in the leach to maximize recovery of REO. Figure 13.8
illustrates the recovery of REO using various acid dosages at 90°C.
