Este trabalho propõe uma metodologia inovadora de seqüenciamento de lavra em minério de ferro a qual, além de considerar os parâmetros operacionais e econômicos das técnicas tradicionais, permite uma abordagem ambiental proativa para sequenciar a lavra de forma a antecipar a exaustão de parte da cava para disposição do estéril dentro da cava final. A metodologia proposta de seqüenciamento ordenado de lavra permite reduzir a área degradada a ser reabilitada na mina, com significativos benefícios associados à reducão do impacto ambiental, sem comprometer as metas de produtividade e competitividade econômica da lavra. A metodologia de seqüenciamento ordenado de lavra foi aplicada em um estudo de caso de projeto de lavra de minério de ferro, e os resultados alcançados comprovaram os benefícios esperados com a aplicação da metodologia proposta. / This paper presents a innovative approach for an environmentally pro-active mine scheduling process. The proposed methodology has been developed for identifying a mine sequence that meets all operational and economical constraints in iron-ore mining, and takes into account a pro-active approach for scheduling the mine according to environmental criteria. The proposed methodology allows a significant reduction of the environmental impact related to the mining operation without compromising productivity and the economical feasibility of the mine. The methodology has been applied to a case study of iron ore mining in Brazil, where the expected benefits have been proven.

Este trabalho propõe uma metodologia inovadora de seqüenciamento de lavra em minério de ferro a qual, além de considerar os parâmetros operacionais e econômicos das técnicas tradicionais, permite uma abordagem ambiental proativa para sequenciar a lavra de forma a antecipar a exaustão de parte da cava para disposição do estéril dentro da cava final. A metodologia proposta de seqüenciamento ordenado de lavra permite reduzir a área degradada a ser reabilitada na mina, com significativos benefícios associados à reducão do impacto ambiental, sem comprometer as metas de produtividade e competitividade econômica da lavra. A metodologia de seqüenciamento ordenado de lavra foi aplicada em um estudo de caso de projeto de lavra de minério de ferro, e os resultados alcançados comprovaram os benefícios esperados com a aplicação da metodologia proposta. / This paper presents a innovative approach for an environmentally pro-active mine scheduling process. The proposed methodology has been developed for identifying a mine sequence that meets all operational and economical constraints in iron-ore mining, and takes into account a pro-active approach for scheduling the mine according to environmental criteria. The proposed methodology allows a significant reduction of the environmental impact related to the mining operation without compromising productivity and the economical feasibility of the mine. The methodology has been applied to a case study of iron ore mining in Brazil, where the expected benefits have been proven.

Underground mining is a complex operation that requires careful planning. The short-term scheduling, which is the scheduling of the tasks involved in the excavation process, is an important part of the planning process. In this master thesis we propose a new method for short-term scheduling of a cut-and-fill mine operated by the mining company Boliden AB. We include a new aspect of the problem by incorporating a priority between the excavation locations of the mine. The priority feature allows the user to control the output of the scheduling and to direct resources to the locations where they are most needed according to the long-term plans. Our solution method consists of two components: a constructive heuristic method that construct a complete solution by solving partial scheduling problems containing subsets of tasks, and a logic-based Benders decomposition scheme for solving these partial problems. The computational performance of the proposed method is evaluated on industrially relevant largescale instances generated from data provided by Boliden. Comparisons are made with applying a constraint programming solver on the complete problem and with replacing the logic-based Benders scheme by applying a constraint programming solver on the partial scheduling problems, respectively. Results show that the heuristic method combined with the logic-based Benders decomposition scheme outperforms the other two methods on all instances.

The task of scheduling mining operations is a strikingly tough task yet it is still largely done manually by hand or with the help of simple gantt planning tools. This thesis aim is to explore the feasibility of an automatic scheduling solution that can incorporate the constraints specific to mining operations. A constraint programming based solution is presented and evaluated based on its correctness, viability and performance. With its rich set of operators, the constraint programming library OR-Tools is able to capture most of the mining specific constraints and two different objective functions are developed to suit different use cases. One is the well established makespan objective which purpose is to minimize the completion time of the last task. The second objective function, named the sub goal deviation objective, minimizes the deviation from the overall production goal divided into sub goals.  The underlying scheduling problem is notoriously hard to solve optimally for large instances. This is supported by several related studies and also by experimental results. To mitigate the performance degradation for large scheduling instances, an iterative solver strategy is presented. With this strategy the scheduler is able to solve much larger instances and initial tests resulted in the same objective values as the optimal strategy. A rescheduling procedure is presented to support schedule maintenance due to unforeseen circumstances such as delays or machine breakdowns. It is concluded that automatic scheduling and rescheduling is feasible but that it first needs to be evaluated by experienced schedulers in the field before being applied in a production environment.