Polygon Based, Maximum Value Pit Design System and Method

摘要

A system and method for pit design that that operates directly on a geological model without creating a three dimensional block model thereby minimizing modeling dilution. A resource in a deposit may be divided into a set of base resource units that closely conform to the resource geometry and value distribution and that can be mined by the equipment assumed to perform the excavation. A resource increment (RI) is defined by a base resource unit and any resource and waste over the base resource unit which is assumed to be excavated in conformance with slope stability and safe practices forming an approximation of a truncated inverted cone. A systematic sorting and grouping process of the RIs iterates down a list of RIs and identifies RIs and/or RI groups that add value to the pit while excluding RIs and/or RI groups that do not add value. The sorting and grouping process operates on the recognition that, for RIs analyzed later in the RI list, the cost of intersections of waste overlaying the RIs base resource unit is carried by RIs analyzed earlier in the list. The sorting and grouping process allows intersecting RIs to be evaluated, grouped into RI groups, and either included or not included in the pit so that a maximum valued pit is defined. One aspect of the novel sorting and grouping process is the identification and grouping of interdependent RIs and RI groups. Another novel aspect of this pit design system is the application of over lapping RI bases with size defined large enough to represent the minimal accessible mining space for the equipment proposed. Larger sized bases should lead to reduction in the complexity of intersecting RIs and computational time. The end result is a model of the pit including a list of RIs and/or RI groups to include in the pit and resource and/or reserve statements.

主权项

1. A method implemented by a pit design system to maximize a value of a pit excavated in a mining operation, said method comprising:
(a) receiving into the processing system a geological model representing resources to be mined; (b) dividing, by the pit design system, resources in the geological model into base resource units; (c) generating, by the pit design system based on the defined base resource units and the geological model, a set of resource increments to excavate the base resource units, each resource increment comprising of a base resource unit and of overlaying material approximating an inverted truncated cone extending upward from the base resource unit to a surface of the pit or the surface reflecting the excavation of all previously processed resource increments; (d) grouping, by pit design system, the resource increments into RI groups comprised of one or more resource increments requires:
(i) identifying two or more interdependent resource increments; and(ii) combining the interdependent resource increments into resource increment groups. (e) determining, by said pit design system, a resource group value for each resource group; (f) sorting, by said pit design system based on the resource increment group values, the resource groups into a first set of resource groups and a second set of resource groups such that:
(i) no resource group in the first set can, if removed from the set, increase the value of the first set of resource groups; and(ii) no resource group in the second set can, if added to the first set, increase value of the first set of resource groups; (g) generating, by the pit design system based on the set of equal to or greater than 0 value resource groups, a list of resource increments to be excavated from the pit.