Echo Bay Mines Materials Handling System

Echo Bay Mines' expansion of its existing heap leach operation to 35,000 tons per day (tpd) involved a large infrastructure scope of work including a new townsite, airstrip, material handling, gold concentrator and process facility. Fluor Daniel performed the detail design, equipment procurement, contract specification and commissioning for the material handling.

Fluor also performed detail engineering and procurement for an 8,000-tpd gold concentrator. The process included primary crushing, single stage SAG milling, two-stage high frequency screening, and three stages of spiral gravity concentration followed by two stages of shaking table gravity concentration. Key aspects of the design included integration of the concentrator into the existing heap leach operating facilities.

Client's Challenge

Echo Bay Mines had sanctioned the investment for a significant capital expansion and infrastructure for its Round Mountain gold mine to increase the capacity and productivity of the operation.

The new, moveable 60/89 crushing plant was designed to produce minus 8 inch crushed ore at a rate of 5,000 tph. To support the increased gold operation output, the expansion also incorporated physical infrastructure for the town and air transportation facilities

Fluor's Solution

Fluor's responsibilities included:

Detailed design of the system from primary crusher to deposition of material on the reusable leach pads
For the new 8,000 tpd gold concentrator, the spiral middlings stream was treated through a cyanide leach/CIP circuit
Technical consulting services for the moveable 60/89 gyratory crushing plant contract
Assistance during evaluation of contract packages
Equipment procurement
Commissioning assistance

The primary crushed ore is stockpiled on a kidney shaped stockpile by a radial, luffing stacker. Reclaim is by four apron feeders to conveyors which transport the material to the crushing and screening plant.

This plant consists of two secondary crushers, four tertiary crushers and four double deck screens. A series of overland belt conveyors transport the 3/8 inch leach pad feed to two reusable leach pads which are 4,000 feet long by 350 feet wide by 40 feet high. The material is deposited by a series of trippers and stackers, and a crawler-mounted bridge conveyor.

Conclusion

A sophisticated series of programmable logic control systems monitor and control the entire operation. The project was completed on schedule and under budget.