allmineral to process Spanish ore at global market quality

Customer Projects 

W Resources deploys a trio of solutions from technology leader allmineral for the construction of its new processing plant in La Parrilla.

The tungsten and tin mine in La Parrilla, Spain, has fully committed to allmineral’s cutting-edge processing technology in order to achieve its ambitious production targets. Having already commenced the design planning and construction of the ‘pre-concentrator’ using two alljig® jiggers, the system specialist received a further order from the mine operator in January 2018. As a result, allmineral will shortly undertake the on-site commissioning of a tailor-made processing plant that represents the final step in the tungsten ore enrichment process.

Located near the Portuguese border, the La Parrilla facility is one of five sites along the Iberian peninsula at which mineral resources are mined by W Resources (WRES). The two alljig® fine-grain jiggers and the adjoining processing plant will help double annual production in the Extremadura region to 5,000 tons within the near future while maintaining the high product quality suitable for the global market.

The mine operator expects that this innovative processing technology will help them recover at least 90% of the metal from the processed ore minerals in the future. Key to this is scheelite, a tungsten mineral that is suitable for enrichment through gravimetric sorting and can even be enriched to form concentrates with a tungsten content of over 66%. La Parrilla also hosts the production of cassiterite, which features a theoretical tin content of 78.8% and is the most important tin ore in the world.

Providing a throughput of 350 t/h, the two alljig® jiggers will ensure reliable and adaptable sorting, enrichment and cleaning of the pre-ground ore. These twin air-pulsed machines conserve resources and remain physically stable during operation, which is a prerequisite for ensuring an optimum jig stroke together with minimum energy consumption. In the alljig® process, the feed material is first fluidised with pulsed water in order to layer the grains according to their density. The jiggers then specifically separate the lighter low-scheelite stock from the heavier scheelite-rich ore in the layered material bed. The jig movement to separate the grains does not cause any wear and is induced by the addition of air, meaning that the stroke movement (frequency, amplitude and waveform) can be configured within a wide range of operating parameters.

Ordered by W Resources in January 2018 as the third core component of the plant infrastructure, the ‘Concentrator’ project will see allmineral perform installation, adjustment and on-site commissioning including all auxiliary units.

Downstream of the pre-concentration performed by the alljig® jiggers, the processing plant with a capacity of 155 t/h will ensure that the tailings are separated from the usable material and thereby achieve 65% WO3 recovery.

The fines generated via several stages of processing will be recovered in a special circuit.

For the Chairman of W Resources, Michael Masterman, the commissioning of the ‘Concentrator’ project from allmineral represents an important milestone and a core component of the development and financing programme at La Parrilla. All the key plant components have now been contractually agreed and adapted in line with the 30 million dollar credit financing. allmineral is responsible for the planning, construction and delivery of the central machine units, which will help simplify and accelerate the implementation of the overall plant in keeping with the specified timeframe and budget.

allmineral wishes to thank W Resources for placing its trust in the company and looks forward to this upcoming collaboration.

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