Forge - December 2008

Mine planning with dynamic, interactive Chronos scheduling

Codelco Norte’s development and planning teams generated a mining sequence delivering significant advantages for operational capacity using dynamic interactive block programming.

During September 2008, Codelco Norte’s Mining Resources and Development Management - Chuquicamata Mine Planning and Development team developed a fortnightly mining plan for the 2009-13 period using Maptek™ Chronos.

One of the main goals was to establish in Chronos the operative load conditions in different sectors of the pit, and the equipment performance that defines the loader fleet in each of these operative conditions. To better represent these situations, 5 load types were defined; the first one corresponding to the ramp opening, up to the last, bench cleaning.

Corresponding operative conditions were assigned to every solid. A performance matrix was then defined, relating the different equipment that makes up the fleet to the different operative conditions. Thus, each of the solids loaded in Chronos has the same information, and can be potentially mined by any equipment match-ing the required conditions. This allows the planners to determine the exact amount of load time needed to mine every block.
Another innovative aspect of this plan was the use of different cut-off grades for every phase in any period. The team was able to specify in detail the material that could be assigned to plant, stockpile or a secondary process. The result was a mine plan which took into account mine requirements, as well as both ore quality and quantity, to optimise the process.

Load targets were also defined for each item of equipment based on the number of operational days per period at Chuquicamata Mine. The mining sequence can be controlled within every phase based on the availability of all equipment.

The location of each item of equipment can be determined accurately on any day during the sequence, thus avoiding interference between equipment located in the same phase.

The inclusion of a worksheet of cut-off grades controlled by phase and period allowed programming to better visualise and plan suitable handling of material to and from the already created stockpiles. The mine plan generates all the information needed for evaluation. It also provides reports at each level of Pit, Phase and Equipment. Codelco Norte’s use of Chronos has delivered significant advantages for operational capacity.