2. Simulation Modelling A Tool to Inform and Support Decisions In Iron Ore Mining Dr Steven Richardson

3. Simulation Models Simulation models are used to imitate real world processes/systems. They are used to study of the system behaviour under specific conditions and based on predetermined assumptions. They allow aspects of the real world to be studied in an accelerated time frame.

4. Uses Identify likely outcomes of specific scenarios; -Evaluating the feasibility/sustainability of potential projects -Comparing alternate mine plan strategies -Maintenance scheduling -Inventory planning Identify key/sensitive operating parameters; Gauge potential variability in core outcomes.

5. What is Involved? The first step is a clear problem statement – What specifically do you want to know about the system? Need to identify output metrics – How will the system performance be measured? Need to identify relevant data/input – Data availability/form guides model boundaries and detail.

6. Process Map

7. Current Projects 1.Decision Support Simulation Model for Tyre Management: Tyre Inventory Levels (ECU/Rio Tinto Iron Ore) 2.Integrated Simulation Model of Mine Haulage and Truck Shop Operations. (ECU/UWA/Rio Tinto Iron Ore)

8. Tyre Management Some of the Questions: – How many tyres will be used at the mine in the next year? – What minimum level of inventory should be maintained in order to avoid significant risk of production losses? – When should tyres be rotated from front to back?

9. Truck Shop Simulation Some of the Questions: – How do Truck Shop resource levels impact production? – What impact does Truck Shop priority strategy impact production? – What is the best frequency with which to schedule Planned/Preventative maintenance?

10. Input Data Example Inputs Travel time between truck shop and shovel Travel time between shovel and crusher/ and return Normal Travel time between crusher and truck shop Loading time at shovel Unloading time at crusher Failure distribution for each truck Failure distribution for each shovel Truck repair time distribution for scheduled work Shovel repair time distribution for scheduled work PM Inspection interval (for each truck) PM Inspection interval (for each shovel)

11. The Model

12. Output Number of repair resources Shovel has Priority Average Production (no of loads) Average Truck Availability Average Shovel Availability 1No1113476.675.1 1Yes11744 (+5.5%)73.3 (-4.3%)83.4 (+11.1%) 2No1463187.686.9 2Yes14713 (+0.6%)87.5 (-0.1%)87.5 (+0.7%) 3No1500588.588.4 3Yes14991 (-0.1%)88.5 (+0.0%)88.4 (+0.0%) 4No1501588.688.4 4Yes15012 (-0.0%)88.6 (+0.0%)88.4 (+0.0%)

13. Conclusion Both projects still in very early stages Interest from Industry Many questions still to be answered