Ultra-Fast Pit Optimizer

GeoMine’s FlowPit is an ultra-fast open pit optimization module. FlowPit implements the industry standard Lerchs-Grossmann’s 3D pit optimization algorithm, but with a novel implementation. FlowPit’s highly efficient and scalable implementation achieves a superior magnitude speed-up in comparison to competitors. For small block models (with about 1 million non-air blocks), FlowPit takes seconds to complete a single optimization run as opposed to hours. For very large block models (with 15~30 million non-air blocks), FlowPit takes full advantage of today’s multi-core CPUs to determine the optimum final pit limit within half an hour. For huge block models (with 50~100 million non-air blocks), without super-blocking, FlowPit Ultimate can determine the optimum pit limit within 3 hours on modern i7 PCs equipped with 32gb ram.

In order to arrive at a solution in a realistic time frame for large block models, most of the existing mine planning software for open pit mining (pit optimisers) use super-blocking to drastically reduce total block counts. Consequently, this materially affects the solution accuracy which has not been quantifiable up until now. Usually a single careless 2x2x2 reblocking can result in a final pit with up to 7% profit loss and a slight pit slope change (please refer to the Impact of Reblocking on Pit Optimization for a detailed analysis). With FlowPit, mine planners no longer need to super-block their block model and even if they do, they now have a proper tool to evaluate the impact of their chosen reblocking configuration on their block model. This advance in computational speed with guaranteed optimality makes FlowPit an effective tool not just for determining the optimal pit limit, but also for Sensitivity Analysis that allows the planner to quickly conduct reliable “what if?” scenario analyses.

FlowPit features a powerful slope modeling sub-module: not only can pit slope angles be varied by sectors and levels, but also can they be varied by both regions and rock types within regions (where other competitors that we know of can only vary the pit slope angle by either regions or by rock types, not both). 

FlowPit also offers a unique Stochastic Optimization option which allows a group of block model realizations as input and thus enables mine planners to quantify, in a single optimization run, geological uncertainty and risks inherent in ant mineral resource projects.