A decision support tool for circular stockpile management using simulation

[摘要] ENGLISH ABSTRACT: The aim of a blending stockpile is to minimise the natural variation in properties of a material deposit. Ingeneral the reduction in variation will result in a more efficient and cost effective downstream process.Stockpile management is an important part of the production manager's duties, as it has a significantimpact on the quality and consistency of the product delivered. Decisions in this regard are mostly drivenby experience and specialised expertise, and a need has been identified to implement scientific methods inthe decision-making process.A representational model-driven personal decision support system was designed which aims to assist thedecision making process of a production planner/manager by providing information about the expectedoutput grade variation from a circular stockpile. The core of the decision support tool is a model thatsimulates the behaviour of a continuous circular blending pile. The development of the simulation modelextended work done by other authors by eliminating the assumptions of constant stacker flow and verticalreclaimer slices. A user interface was developed that makes the complex calculations behind the simulationeasily accessible to planning and operational personnel.The validity of the simulation model was evaluated by using data from a case study. It was found that theconeshell model offers a reasonable representation of reality in the way that it simulates the movement ofthe stacker and reclaimer units around the pile, and proved able to predict peaks and troughs in the outputgrade to within 4% of the recorded values. Preliminary validation of the chevcon model delivered positiveresults, but further validation measured against recorded data would be necessary before implementationis considered.The simulation model was also used to investigate the sensitivity of blending efficiency to various inputparameters. Under optimised conditions the output variance generated by the chevcon model was half ofthat achieved with coneshell stacking, proving that the investment in chevcon stacking infrastructure is onethat every production facility seeking improvement in output grade consistency should consider.The research objectives set at the start of the study have been achieved, and results indicate that thedecision support tool can be used to predict and the consistency of material grade as reclaimed from acircular blending pile.

[发布机构] Stellenbosch University