Douglas Batista Mazzinghy

HPGR simulation from piston-die tests with an itabirite ore

The Minas Rio project, owned by Anglo American, has HPGRs in open circuit operated as a tertiary/quaternary crushing stage. Currently this type of equipment is designed from HPGR tests on laboratory scale and pilot scale tests. This paper presents a methodology for simulating HPGR from piston-die tests on laboratory scale and a mathematical model developed in Hacettepe University in Turkey. The parameters determined from the results of the piston-die tests were used to validate the HPGR testing on pilot scale. Finally, the model was used to predict the particle size distribution in the HPGR product on industrial scale.

PRÁTICAS DO PMBOK® APLICADAS A ÁREA DE DESENVOLVIMENTO DE PROCESSOS

Resumo Atividades de pesquisa e desenvolvimento (P&D) possuem efeito positivo nos indicadores econômico-financeiros das organizações. Essas atividades possuem características de projetos, e, por isso, podem ser submetidas aos processos de gerenciamento recomendados pelo PMBOK. As atividades da gerência de P&D do Minas-Rio da Anglo American foram submetidas à alguns desses processos. Inicialmente, foram estratificados os processos por magnitude de esforço e de impacto. Oito processos foram classificados como de baixo esforço e alto impacto e, por isso, totalmente implementados. A criação e aplicação de três ativos organizacionais padronizados para todas as atividades realizadas permitiu o desenvolvimento de grande parte dos processos considerados mais importantes. Um questionário de avaliação do grau de maturidade em gerenciamento de projetos foi respondido por parte da equipe antes e depois da adoção formal de tais processos. O grau de maturidade aumentou significativamente, 150%, em dois anos, passando do nível conceitual para padronizado. Além disso, foi observada um aumento significativo, igual a 731%, no número de atividades realizadas pela área. Palavras-chave: Gerenciamento de projetos; laboratório de pesquisa e desenvolvimento; PMBOK.

Simulations of Vertimill Pilot Scale tests for Itabirite

The Minas-Rio Project is the biggest project from Anglo American in the world and considers Vertimill in the regrinding circuit to adequate the particle size distribution to feed slurry pipeline that will pump the ore from Conceicao do Mato Dentro in Minas Gerais State to Acu Port in Rio de Janeiro State, Brazil. A Vertimill pilot test campaign was carried out at Metsos pilot plant facility located in York city, Pennsylvania State, USA, to provided information to sizing the industrial grinding circuit. The main objective of this work is proposing a way to simulate the industrial Vertimill using the population balance model, normally used to simulate ball mills. The simulations were based on the selection and breakage functions determined from the laboratory tests using a batch ball mill. The simulations were performed using a Vertimill model implemented in the ModsimTM plant-wide simulator. The results of simulations shows that was possible to simulate the pilot tests, with good accuracy, considering simple laboratory tests with small quantities of samples.

Simulation of a ball mill operating with a low ball charge level and a balanced ball size distribution

The optimization of industrial grinding circuits has been successfully performed using mathematical models that describe the industrial scale data from breakage parameters determined in laboratory grinding tests. The test material studied here is a gold ore ground in a closed ball mill circuit with hydrocyclone classification. Several sampling campaigns were carried out aiming to produce mass balances and provide material for laboratory tests. The parameters determined in the laboratory tests were used to predict, by simulation, the circuit behavior with a low ball charge level and a balanced ball size distribution.