Michael Masterman, Chairman of W Resources PLC LON:WRES said: “As we make good progress at La Parrilla, we are pleased to see our plant design and mine development underpinned by strong 70% plus metal recoveries. These results underpin the low capital and operating cost of the project and pave the way for plant engineering which is now underway and we remain on track for first production by the end of 2016.”
W Resources Plc (LON:WRES), the tungsten, copper and gold exploration and development company with assets in Spain and Portugal, has told DirectorsTalk about strong metal recovery results for its La Parrilla Fast Track Mine (‘FTM’) in Spain, from extensive test work conducted in Europe over the last quarter. End to end recoveries through the process plants circuit are estimated at 71% overall WO(3) recovery.
The results confirm that the coarse grain nature of the tungsten and tin mineralisation at La Parrilla allows very efficient gravity recovery of the tungsten and tin concentrate at low cost. Waste is easily separated without the need for advanced technologies. Metal recovery is achieved in phase 1 by a jig and mill circuit and upgraded in the existing concentrator. The plant will be designed to optimise recovery with a production rate of 1,300 tonnes per annum (‘tpa’) of concentrate with the in-built capacity to expand at very low cost to 2,600 tpa.
In addition, comprehensive X-Ray ore sorting has confirmed >93% metal recoveries can be achieved by treating two sized feed streams. The development plan and start-up design will allow installation of ore sorters in the crushing plant in phase 3 to increase capacity to 5,000 tpa of concentrate allowing an efficient expansion. Incorporation of X-Ray sorters in the later phase allows a streamlined initial start-up in the most critical phase 1.
Concentrator optimisation tests revealed further WO(3) recoveries can be captured by applying simple gravity separation techniques. A 4% gain in WO(3) recovery was measured during feed size optimisation testing. Basic modelling indicates that a further 10% metal can be recovered when simulating the process flowsheet in closed circuit for a total of 14% increase in metal recovery over and above baseline testing.
The increase in metallurgical recovery above the previous baseline testwork program is realised primarily by segregating the feed streams into discrete sizes prior to processing and returning high grade tails streams, and middling streams back to the feed while maintaining product quality. W anticipates producing a tungsten product at 66% WO(3) with arsenic levels less than 0.15% and all deleterious elements reporting below analytical detection limits.
