Comparison between the application of the conventional mine planning and of the direct block scheduling on an open pit mine Project

Pedro Henrique Alves Campos,Carlos Enrique Arroyo Ortiz,Ivo Eyer Cabral,Nelson Morales

doi:10.1590/0370-44672017710037

Abstract

Abstract Historically, since the 60's, traditional mine planning consists of several distinct stages: 1) Definition of the ultimate pit - the portion of the blocks that results in the greatest total value; 2) Pushback selection - based on the generation of nested pits, obtained with the change in the value of the ore price; 3) Long-term production scheduling. Although considered quite satisfactory, this methodology presents some flaws: The stages, even if considered individually optimal, may not be when put together. The opportunity cost is not considered and the cut-off is fixed. Due to the recent computational advances, a new technique has been growing and is more reliable: the direct block sequencing. In this methodology, the steps are consolidated into only one process, improving the economic results, reducing the total execution time and obtaining, in fact, an optimal planning. The aim of this work is to compare the results of the two planning methods applied in a database of a Brazilian iron ore mine and to show the real advantages and disadvantages of each one. To solve the direct block sequencing technique, Doppler was used, a tool developed by Delphos Mine Planning Laboratory, located at the University of Chile. The traditional methodology was executed through Whittle software. Lastly, a medium-term scheduling was performed using Deswik software.

Highlights

Comparison between the application of the conventional mine planning and of the direct block scheduling on an open pit mine project AbstractHistorically, since the 60's, traditional mine planning consists of several distinct stages: 1) Definition of the ultimate pit - the portion of the blocks that results in the greatest total value; 2) Pushback selection - based on the generation of nested pits, obtained with the change in the value of the ore price; 3) Long-term production scheduling
As a result of Whittle's strategic was obtained with 1.56 billion tons of NPV of $ 2.88 billion (Figure 3). planning, a 43-year production plan ore mined, 86 million of waste, and
The production plan generated with Whittle was developed according to what is done by the mineral industry, that is, accomplished through the analysis and experience of the planner, where a feasible production plan with satisfactory economic results was sought

Summary

Introduction

Since the 60's, traditional mine planning consists of several distinct stages: 1) Definition of the ultimate pit - the portion of the blocks that results in the greatest total value; 2) Pushback selection - based on the generation of nested pits, obtained with the change in the value of the ore price; 3) Long-term production scheduling. Due to the recent computational advances, a new technique has been growing and is more reliable: the direct block sequencing. In this methodology, the steps are consolidated into only one process, improving the economic results, reducing the total execution time and obtaining, an optimal planning. The traditional methodology was executed through Whittle software. A medium-term scheduling was performed using Deswik software

Objectives

Methods

Results

Discussion

Conclusion