DeGrussa Paste Backfill Plant
Sandfire Resources NL (ASX:SFR)
900km north of Perth and approximately 150Km north of Meekatharra
Scope of work:
GR Engineering was appointed by Sandfire Resources NL to undertake the design and construction of a 120m3/hr paste backfill plant at the DeGrussa mine site. The project was completed under an EPC based contract.
Sandfire free issued to GR Engineering a 96m2 horizontal belt filter and associated equipment. This included a vacuum pump, filtrate receiver and filtrate pump, all to be incorporated into the paste plant design. The engineering and design was completed by GR Engineering's design team. Process design was overseen by Bill Gosling who has a wealth of experience in design and commissioning of paste plants.
GR Engineering contracted the supply of a 600t cement storage, delivery and mixing system to Batchcrete International. All other major equipment for the project was procured locally.
The process involves the pumping of deslimed tails from the concentrator, a distance of 2km, to the paste plant location. Material is then stored in a 1000m3 agitated filter feed tank and from there pumped across to the horizontal cloth filter. Filter cake is then conveyed to a paste mixer where at this point controlled cement and water is dosed to achieve the desired paste mix. Paste is then gravity fed down the underground bore hole. To increase flexibility of the paste backfill plant it has been designed to introduce alternate material to the mixer independent of the filter operation. The result is a hybrid system that can produce paste solely from concentrator live tailings, solely from other materials or a combination of both. The designed operating volumetric flow is 85m3/hr with excursions to 120m3/hr being allowed for.
The project was completed without a lost time injury, on schedule and within budget.