Ingeniero Civil de Minas / En la gran minería a cielo abierto, los sistemas pala-camión son ampliamente usados para realizar la labor de carguío y transporte. Actualmente este ítem abarca cerca del 50% de los costos de operación y en donde las principales mejoras se logran a través de una gestión óptima de la disponibilidad, confiabilidad y mantenimiento del sistema. En el caso de la minera en estudio, el costo Planta asciende al 48% del costo de caja, y el 25% de este último corresponde al costo del chancado. El principal objetivo de este estudio es determinar el ritmo de producción de Minera Antucoya en plena operación, en base a las variables y supuestos determinados en la fase de proyecto y construcción, incluyendo en cada uno de los equipos del procesamiento de mineral, sus tiempos de reparación y entre fallas, aplicados en base a distribuciones de probabilidad. La metodología aplicada a este trabajo consta del desarrollo de un modelo de simulación basado en un modelo conceptual, que detalla supuestos, parámetros, variables, criterios de diseño y operación utilizados, que permiten una comprensión del sistema modelado. La codificación el modelo en la plataforma ProModel® obtiene como resultado una producción anual de 30,77 Mt. Luego de calcular la simulación terminante, se comprueba que con sólo una corrida es suficiente. El paso siguiente fue calibrar el modelo para generar un sistema que soporte capacidades de emergencia en caso de déficit de producción. Luego de esto se validaron por partes y verificaron los indicadores para equipos principales de las tres etapas de chancado. Su resultado fue una producción de 32,76 Mtpa, lo que equivale a un beneficio marginal de US$ 27,4 MM. Se recomienda continuar este estudio, de manera de poder replicar las condiciones de la operación con una base de datos actualizada, considerando al menos aumentar el límite de batería hasta las pilas de lixiviación, para de esta forma obtener estimaciones más cercanas a su real desempeño. / In large scale open pit mining, shovel-truck system are widely used for loading and haulage labors. Actually, this item represents nearly 50% of operating costs, where main improvements are achieved through optimal management of availability, reliability and maintenance of the system. In this particular study case, processing costs reach 48% of cash costs, where 25% of this given cost comes into the crushing step. Main purpose of this study is to determine the production rate of Antucoya Mining in full operation, based on variables and suppositions determined during the project and construction phases, including for each processing unit, its maintenance times between malfunctions applied on probabilistic distributions. The methodology applied for this study includes the development of a simulation model based on a conceptual model, which specifies suppositions, parameters, variables, design and operation criterion that allow a comprehensive patterned system. The code lines of the model used in ProModel® platform delivers an annual production rate of 30.77 Mt. After calculating the finishing simulation, it is proven that a single run is enough. The next step is to calibrate the model to generate a system that supports emergency capacities in case of a lacking production. After this, the indicators for the 3 main crushing stages were validated and verified individually. With this, a new production of 32.76 Mtpa is achieved which represent a marginal profit of US$ 27.4M. It is advised to further continue this study in order to replicate the operating conditions using updated data and increasing at least the battery limit to leaching piles, allowing the model to obtain more realistic estimations. / 28/7/2021

The present project discusses the application of screening techniques in large-scale simulation models with the purpose of determining whether this kind of procedures could be a substitute for or a complement to simulation-based optimization for bottleneck identification and improvement. Based on sensitivity analysis, the screening techniques consist in finding the most important factors in simulation models where there are many factors, in which presumably only a few or some of these factors are important. The screening technique selected to be studied in this project is Sequential Bifurcation. This method consists in grouping the potentially important factors, dividing the groups continuously depending on the response generated from the model of the system under study. The results confirm that the application of the Sequential Bifurcation method can considerably reduce the simulation time because of the number of simulations needed, which decreased compared with the optimization study. Furthermore, by introducing two-factor interactions in the metamodel, the results are more accurate and may even be as accurate as the results from optimization. On the other hand, it has been found that the application of Sequential Bifurcation could become a problem in terms of accuracy when there are many storage buffers in the decision variables list. Due to all of these reasons, the screening techniques cannot be a complete alternative to simulation-based optimization. However, as shown in some initial results, the combination of these two methods could yield a promising roadmap for future research, which is highly recommended by the authors of this project.