The testing is being conducted at the University of Minnesota-Duluth's Natural Resources Research Institute (NRRI) in partnership with Weir Minerals. During the testing, which is expected to take several weeks, approximately 3t of Elk Creek drill core will be reduced to the 1mm size needed for hydrometallurgical testwork.
HPGR technology is an energy efficient and low-emission alternative for reducing the size of the ore to enable the recovery of niobium, scandium, titanium and potential rare earth products. NioCorp said that the use of HPGR in the project reinforces its commitment to the environment and designing a sustainable operation.
The testwork is expected to provide key data that will be used to properly size the HPGR unit for the potential ore throughput at the Elk Creek project once project financing is secured and the project is operational.
NioCorp is currently evaluating next steps in its overall metallurgical testwork programme, which will focus on optimising and streamlining the existing processing flowsheet as well as establishing process routes for the potential recovery of rare earth products.
In March, NioCorp launched a review of the economic potential of expanding its planned product suite from the Elk Creek superalloy materials project to also include rare earth products. The rare earth products that are currently of the most interest to the company are neodymium-praseodymium oxide, terbium oxide and dysprosium oxide.
Scott Honan, COO of NioCorp, said: "After witnessing testing at NRRI, I was impressed with how the HPGR was able to handle the Elk Creek ore quickly and efficiently, with minimal noise and dust. We look forward to completing this phase of the testwork and moving on to look at further improvements to the existing flowsheet, including our new emphasis around the rare earths."
Weir Minerals and NRRI also teamed up in June 2020 to test HPGR technology in the Iron Range region of Minnesota, US. In April this year, Weir won a major comminution technology order from Ferrexpo in Ukraine that included its Enduron HPGRs.