Iron Road optimises planned mine in South Australia and reduces CAPEX Wednesday, 14 October 2015

Iron Road has completed Class 3 mine optimisation studies at its Central Eyre Iron Project in South Australia, lowering the proposed mine and plant’s operating costs, improving efficiencies and reducing delivery risks.

Opportunities for vendors, subcontractors and Engineering Procurement Construction contractors are likely to arise shortly.

The Central Eyre Iron Project (CEIP) is a second generation and coarse-grained magnetite development. It includes a proposed long-life mine, processing plant, and rail and port infrastructure.

Iron Road engaged with industry experts to assist with the optimisation studies, including Thiess RWE and MMD.

A major part of the optimisation studies was to assess the use of In-Pit Crushing and Conveying (IPCC) processes in the proposed open pit mine, rather than conventional truck and shovel, load and haul mining. This would result in reduced diesel consumption, and also ensure the operation moved material such as waste rock, ore and tailings in the most efficient way possible.

The optimisation studies also enhanced the flowsheet design, with a simpler plant layout, smaller footprint, and lower overall power demand compared with existing magnetite operations. The new design calls for the use of semi-autogenous grinding technology, with waste progressively separated and removed between grinding and recovery stages, in order to simplify material handling throughout the system.

The project will also make use of a modularised approach for its Ore Processing Facility, which will process up to 175 Mtpa (dry) of feed material. The process modules will be fabricated, pre-assembled and commissioned off-site, on the southeast edge of the proposed pit.

The facility will have three discrete processing trains, each incorporating seven main modules: Semi-Autogenous Grinding Mill; Rougher Magnetic Separator; Gravity Beneficiation Circuit; Regrind Mill; Ball Mill; Cleaner Magnetic Separator; and Tailings Filter Building.

Optimisation has resulted in revised capital expenditure associated with the project: total CAPEX has dropped from US$4575.64 million as estimated on 31 March 2015, to US$4305.38 million.

According to Iron Road managing director Andrew Stocks, the optimisation work improves on the findings of the 2014 Definitive Feasibility Studies, by addressing in detail both the mine plan and the full suites of associated plant required over the life of the operation.

“The optimisation work has achieved its aim of reducing delivery risk and operating costs estimates through detailed planning and improved flexibility, especially in the new mine design,” Stocks said.

“We have continued to fine-tune the process plant layout and modularisation strategy and we are now updating our reserve estimate accordingly.”

Stocks noted that the optimised rail and port facilities will have sufficient capacity for an expansion of operations. Capacity could also be leased out to third parties such as grain producers.