AAOM Handbook
[OFFICIAL]
INTERNAL USE ONLY
Step 1: Modelling the Mine ‘Unconstrained Output’ of valuable mineral: The Unconstrained column is the column that indicates the process’s stable, independent and representative operating performance, as dependent variation has been excluded. This is determined from the Control Chart of the process measure. The distribution and its associated parameters of the unconstrained column are obtained from historical data of the specific process, as the base-case scenario over the calibration period. The accountable person will need to type in the equation as depicted in Figure 11 into the first empty cell of period 1. Figure 11 - Pert distribution used to calculate the unconstrained column • The formula depicted in Figure 11 references the inputs recorded in the Inputs tab. The format of the PERT distribution is RiskPert(min, most likely, max), where cell D22, D23, D24 represent minimum, most likely and maximum respectively. The RiskPert function is an @Risk function. • The accountable person then drags this formula down initially for a period 365 days if the operating level is applicable for the full year or assign different input parameters as defined in the Inputs as shown in Figure 12 below. A period of 1 year is sufficient as a base case scenario to calibrate the model, however scenarios and performance targets have to be generated over 5 years as required by the Business Expectations in the 5-year Business Plan. Figure 13 shows an example normalized to valuable mineral.
MINE Unconstr. Output (Total tonnes)
Unconstr. Output (FGO tonnes) - Total
Unconstr. Output (FGO tonnes) - MSC
Unconstr. Output (FGO tonnes) - MNC
Unconstr. Output (FGO tonnes) - Baobab
Unconstr. Output (VLGO tonnes) - Total
Unconstrained Output (Waste Tonnes) - Total
9,166 39,310 68,054 63,204
2,750 11,793 20,416 18,961
6,416 27,517 47,638 44,243
0 0 0 0
10,801 8,466 2,426 15,590
212,706 284,002 195,619 156,245
232,673 331,778 266,099 235,040
Figure 12 - Example Mine Process modelling
Design
Mine
Beneficiate Beneficiate (MSC) Beneficiate (MNC) Beneficiate (Baobab)
Unconstr. (Pt oz)
Unconstr. Prod'n (Pt oz)
Unconstr. Prod'n (Pt oz)
Unconstr. Prod'n (Pt oz
Unconstr. Prod'n (Pt oz)
Unconstr. Prod'n (Pt oz)
1,165 1,823 1,233
334
1,425 1,507 1,264
370 370 411
988 978 765
0
1,386 2,399
98 95
Figure 13 - Example Normalized valuable mineral across value stream
Operational Planning: Building a Business Structure Performance Model Page 16 of 39
Made with FlippingBook - Online Brochure Maker