Influence of goethite on the Transportable Moisture Limit of iron ore fines
Influência da goethita no Limite de Umidade Transportável de finos de minério de ferro
Raphael Lessa de Paula; Rodrigo Fina Ferreira; Rosa Malena Fernandes Lima
Abstract
Iron ore is a major seaborne commodity, and its transport is regulated by the International Maritime Organization (IMO). To prevent excess moisture related accidents, the IMO sets a Transportable Moisture Limit (TML) for iron ore fines, which is the moisture content at which the material reaches 80% saturation, determined through laboratory tests. Recent research has shown that TML is influenced by a variety of factors, including particle size distribution, mineralogical composition, and solids density. However, the influence of goethite on TML has not been fully explored, and this was the subject of the present work. The results show that goethite content is positively correlated with TML. Samples with higher goethite content exhibited reduced compaction, leading to larger void volumes within the compacted material. This reduced packing density likely contributes to the higher TML observed. Goethite’s lower solids density is also a relevant contributing factor. Further research is needed to understand the specific mechanisms underlying the differences in compaction behaviour and its impact on different iron ore compositions.
Keywords
Resumo
O minério de ferro é uma das principais commodities transportadas via marítima e seu transporte é regulamentado pela Organização Marítima Internacional (IMO). Para prevenir acidentes relacionados a excesso de umidade da carga, a IMO estabelece um Limite de Umidade Transportável (TML) para os finos de minério de ferro, que corresponde à umidade na qual o material atinge 80% de saturação, determinada por testes laboratoriais. Pesquisas recentes demonstraram que o TML é influenciado por diversos fatores, incluindo granulometria, composição mineralógica e densidade dos sólidos. No entanto, a influência da goethita no TML não foi explorada a fundo, tendo sido o objeto de estudo do presente trabalho. Os resultados mostraram que o teor de goethita está positivamente correlacionado com o TML. Amostras com maior participação de goethita apresentaram menor compactação, levando a um maior volume de vazios no material compactado. Esta menor densidade de empacotamento contribui para o TML mais elevado. A menor densidade dos sólidos da goethita também é um fator contribuinte relevante. Pesquisas adicionais são necessárias para entender os mecanismos específicos relacionados às diferenças no comportamento frente à compactação e seu impacto em diferentes composições de minério de ferro.
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References
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Submitted date:
01/25/2024
Accepted date:
07/08/2024