Zinc-focused Trevali Mining Corporation (TMC) says that the ramp-up of the processing plant serving its zinc/lead/silver-producing Santander mine, in west- central Peru, is progressing well, having recorded a 75% use of its capacity in August, with the expectation that it will operate at full capacity by 2014.

Since the start of production at the mine in August, TMC has seen mill performance and commissioning ramp up steadily, improving from 500 t/d to between 1 500 t/d and1 600 t/d, which is about 75% of its nameplate 2 000 t/d capacity, the company adds.

“We are encouraged with the excellent progress being achieved in the Santander mill commissioning, which is a testament to the dedication and skills set of the operations team,” says Trevali president and CEO Dr Mark Cruise.

The metallurgical recovery circuits are also seeing steady improvements as the reagent/ flotation process gets balanced through the ramp-up process. During the month of August, the processing plant processed low-grade material to allow operators to become acquainted with the plant.

The Santander team is now steadily increasing mineral head grades in addition to increasing the mill feed towards expected nameplate hard-rock/stockpile production levels.

To date, processing has yielded 35 000 tonnes, according to TMC, with zinc concetrate production accounting for 1 200 tonnes at an average of 49% zinc. Lead/silver concentrate production accounts for 1 300 tonnes at an average of 49% lead and 47 oz/t silver.

Since start-up, zinc recovery has been recorded at 73%, compared with lead at 78% and silver at 58%. To date, zinc recovery has increased by 4%, lead recovery by less than 1% and silver by 6%.

The company says, now that sufficient initial mineral processing and concentrate data has been acquired, Trevali’s consulting metallurgist will be on site to help further improve plant operations and increase recoveries. It is also expected that commissioning of the office automation system/courier system – a real-time plant geochemical analysis system – later in the month should also have an additional positive effect on mineral recoveries.
The company currently has about 160 000 t of mineralised materials stockpile at its crusher pad that is feeding the mill.
“With significant concentrate inventory now in our on-site warehouse facilities, our maiden concentrate shipments are scheduled to start in late September,” says Cruise.