Batu Hijau Copper-Gold Mine, Indonesia

Batu Hijau is definitely an open-pit mine. Ore is transported towards the priMtw Series Trapezium Mill Supplier mary crushers using P&H 4100 electric mining shovels and a fleet of 220t-capacity Caterpillar 793C mechanical-drive haul trucks. The mine typically handles around 600,000t d of ore and waste, the ore grading an average 0.49% copper and 0.39g t gold.

Following primary crushing, the ore is transported to your concentrator by an overland conveyor, 1.8m wide and 6.8km long. The concentrator circuit consists of two-train SAG and ball mills, followed by primary and scavenger flotation cells, vertical regrind mills and cleaning flotation cells to produce a copper-gold concentrate grading 32% copper and 19.9g t gold. Counter-current decantation thickeners are used to dewater the concentrate to a slurry, which is pipelined 17.6km from the plant towards the port at Benete. Here it is dewatered further, then stocked in an 80,000t-capacity storage area prior to shipment by sea.

PRODUCTION

During 2005, Batu Hijau produced and shipped 1.1Mt of copper concentrate containing 325,500t of copper and 719,000oz of gold.

TAILINGS DEPOSITION

The tailings from the operation flow by gravity from the process plant towards the ocean where they are deposited 3km from the coast at a depth of about 108m. From there, the tailings, which are non-toxic and non-hazardous, migrate towards the Java Trench and are ultimately deposited at depths in excess of 4,000m.

ENVIRONMENT

There are considerable environmental challenges at Bata Hijau, including steep terrain and widely dispersed facilities stretching over 40km. The site has a tropical monsoonal climate with high rainfall, and an extended arid season with almost no rainfall. Other environmental considerations include significant seismic activity, with the associated risk of tsunamis, and acid rock drainage, not to mention the existence on site of an endangered species, the yellow-crested cockatoo.

Considerable...