Phoenix Project - Newmont Gold 

The Phoenix Project was a low capital cost venture into reopening a shut-down Copper & Gold operation. The Flowsheet includes primary crushing followed by a single stage SAG Mill circuit and two Ball mills, Flotation circuit for the bulk sulfides (Cu/Au/Ag),Coarse gold recovery circuit on the copper concentrates, desliming cyclones on the flotation tails prior to agitated CN leach circuit and a lined tailings dam. The plant was completed 15 months after first pour of concrete at slightly above budget.

Tintaya Oxide - BHP Copper

High grade but small capacity SXEW circuit built in Southern Peru that was capital cost efficient. Flowsheet includes a two-stage wet screening for slimes removal and a separate in a CCD circuit using E-Cat high capacity thickeners for treatment. The coarse ore fraction is then crushed and placed on a “Dynamic” Heap Leach pad. Leach solutions are combined and treated in a reverse-flow SX configuration before going to the EW circuit, where "acid mist" is captured by individual cell hood system. The plant achieved design rates within the first month of operation at below forecasted Opex.

Project Management

Freeport Indonesia - FCX

Starting in 1985, the mine went into a series of expansions and the mill capacity was doubled every 18 months from 12.5k to 52k mtpd. During this expansions plant improvements were also made  that resulted in metal recovery increases; Copper by 5% and Gold by as much as 10%. These improvements included: Inclined cyclones with Flash Flotation, crusher speed increases achieving a 5 micron product combined with primary wet screening, two-stage column flotation for final concentrate cleaning, Tower mill regrinding for concentrate pipe transport (100k) protection, and Expert Process Controls systems for both grinding and flotation column circuits.

 

Continuous Improvement

Jerritt Canyon - Freeport Gold

Original Grinding Circuits were single stage SAG mills followed by  Ball mills. Because the initial Oxide ores were "Jasperoid " and had higher than expected work index, the mill capacity was less than 50% of design. By successfully converting to an  ABC grinding circuit, the throughput was increased to over 15% of design while lowering operating cost to less than plan.

What Really Matters 

The Most Important Thing is to define Your Goals 

JohnsonMCS will assist in this process for each stage. Below is an example of key discussion topics for the Project Identification or Concept Development Phase:

  • Define outcomes to be achieved (Strategic Business Objectives or SBOs)
  • Identify minimum scope required to achieve the SBOs  
  • Initially engage stakeholders
  • Screen potential projects and options
  • Ensure that an initial risk register has been assembled and that large areas of uncertainty have been identified together with the strategies to reduce these uncertainties in the next stage
  • Define resource allocations in terms of time, money and management
  • Confirm that adequate managerial and other resources exist to undertake the next steps in the program

Inputs considered during this stage may include:

  • Competitor Intelligence or Other Competitive Studies
  • Environmental Constraints and Regulations
  • Value Added Assessments
  • Technology Assessments including Required R&D
  • Estimates by Others
  • Stakeholder Surveys and Other Assessments
  • Program or Product Development
  • Business Objectives