Metodologia de avaliação econômica para flexibilização operacional e aproveitamento dos minérios e frentes marginais em uma mina subterrânea

Abstract

Business structures increasingly require creative effort, technological and engineering development, as well as a constant critical review of existing practices, seeking to maximize financial returns and minimize negative socio-environmental impacts among those involved. In the mining context, this demand is no different. Mining projects need to be attractive in terms of business, which requires high technical and management performance. The usual fluctuations in commodity prices put pressure on projects till the point of making them economically unviable or unattractive, therefore, a series of risks and opportunities need to be evaluated with due care and attention. The present research aims to present an economic evaluation methodology for underground mines, focusing on the use of ore and marginal fronts to increase the flexibility and financial margin of the business. However, it is intended to detail the production costs, according to the type (SIB, G&A, fixed and variable) and location (Stope, development and metallurgical plant), calculate the standard and marginal cutoff grade, economically evaluate an underground mine, identify bottlenecks and operational idleness, classify the marginal options at a technical/economic level and financially compare sequenced production plan. The rational and methodological use of marginal ores provide financial maximization of the mining enterprise, with 5.5% reduction in AISC and 16.3% increase in revenue, improving operational flexibility and the use of installed resources.