Hybrid configurations for block cave operations

Authors: Eustace, C; Hynard, K; Mariager, S; Fargher, M Download Paper

Cite As:
Eustace, C, Hynard, K, Mariager, S & Fargher, M 2024, 'Hybrid configurations for block cave operations', in Daniel Johansson & Håkan Schunnesson (eds), MassMin 2024: Proceedings of the International Conference & Exhibition on Mass Mining, Luleå University of Technology, Luleå, pp. 1522-1536.



Abstract:
A hybrid operating strategy is planned for Block Cave production at BHP’s Carrapateena mine, located in South Australia. The strategy combines the efficiency of a conventional drawpoint to tipple (direct-tip) operation with an Extraction Drive (EXD)-loop configuration to significantly increase production capacity. Drawpoints closer to the tipple are bogged using a direct-tip configuration, while drawpoints further from the tipple are bogged using an EXD-loop configuration, which allows more Load-Haul-Dump machines (LHD’s) to operate effectively within a pair of EXD’s. In addition to increasing capacity, the approach also provides flexibility to improve management of draw rates across the production footprint. A detailed simulation model of the production level operations is used to test the capacity of the Block Cave while maintaining strict draw compliance. The model includes all LHD movement details, automation system processes and battery change details for scenarios where battery-electric LHD’s are used. Hang-ups, oversize and secondary break requirements and the interface with downstream materials handling systems are also accounted for in the model. This paper provides an assessment of the capability of the Carrapateena Block Cave production level operating under a hybrid configuration, highlighting the decision logic used to maintain draw compliance and throughput at production targets. The assessment demonstrates that throughput can be scaled to approximately double what would otherwise be able to be achieved using a conventional direct-tip approach. Production performance outcomes are broadly applicable to other block cave operations, particularly those that will move to, or are being designed as an electric mining operation.