All articles published by MDPI are made immediately available worldwide under an open access license. No special permission is required to reuse all or part of the article published by MDPI, including figures and tables. For articles published under an open access Creative Common CC BY license, any part of the article may be reused without permission provided that the original article is clearly cited.
Feature Papers represent the most advanced research with significant potential for high impact in the field. Feature Papers are submitted upon individual invitation or recommendation by the scientific editors and undergo peer review prior to publication.
The Feature Paper can be either an original research article, a substantial novel research study that often involves several techniques or approaches, or a comprehensive review paper with concise and precise updates on the latest progress in the field that systematically reviews the most exciting advances in scientific literature. This type of paper provides an outlook on future directions of research or possible applications.
Editors Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to authors, or important in this field. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.
Filippov, L.O.; Silva, K.; Piarra, A.; Lima, N.; Santos, I.; Bicalho, L.; Filippova, I.V.; Peres, A.E.C. Iron Ore Slimes Flotation Tests Using Column and Amidoamine Collector without Depressant. Minerals 2021, 11, 699. https://doi.org/10.3390/min11070699
Filippov LO, Silva K, Piarra A, Lima N, Santos I, Bicalho L, Filippova IV, Peres AEC. Iron Ore Slimes Flotation Tests Using Column and Amidoamine Collector without Depressant. Minerals. 2021; 11(7):699. https://doi.org/10.3390/min11070699
Filippov, Lev O., Klaydison Silva, Alexandre Piarra, Neymayer Lima, Iranildes Santos, Leandro Bicalho, Inna V. Filippova, and Antonio E.C. Peres 2021. "Iron Ore Slimes Flotation Tests Using Column and Amidoamine Collector without Depressant" Minerals 11, no. 7: 699. https://doi.org/10.3390/min11070699
This investigation addressed the processing of ultrafine tailings (slimes) from an iron ore concentrator via reverse cationic flotation to produce pellet feed fines, despite the traditional view that ultrafine particles do not float.
Following size analyses, chemical and mineralogical characterisation, desliming and flotation tests were performed aiming at verifying the flotation behaviour of the slimes. Different dosages of collector and depressant were used.
The promising results of the laboratory scale tests led to carrying out pilot scale tests with the currently produced slimes, and the slimes that will be generated in the future, after the commissioning of the mining companys expansion project.
It was observed that a reverse cationic column flotation process, using high depressant dosage, was selective, yielding high grade concentrates with low impurity content at high levels of iron recovery, approximately 60% mass recovery and 80% metallic recovery in the flotation stage. Excellent valuable product grade (less than 1% silica) and reject product grade (approximately 12% iron) were achieved, resulting in high selectivity levels. The overall mass recovery reached 20%.
Iron ore slimes recovery is the most important issue in iron ore industry in Brazil.Two slimes sample from Quadrilterro Ferrfero (Brazil) were studied in this work.Collector type amide-amine and column flotation were applied to reverse flotation.Flotation results indicates distinct behavior depends on the slime sample.Very good flotation results were obtained with one of the slime sample.
In general, the industrial flowsheets for the beneficiation of itabirite iron ores from the Quadriltero Ferrfero (Minas Gerais state) in Brazil involves grinding, desliming, magnetic separation and cationic reverse flotation using both mechanical and columns flotation cells. At Brazilian plants, it is estimated that Fe losses generated at the slimes stage range between 8% reaching values higher than 20%. Slimes generated at hydrocyclone containing particle sizes of approximately 99%<45m, 25%>10m, 45%<5m and 15%<1m, 3% of solids by weight and between 35% and 45% of Fe grade. This work aims at evaluating the technical feasibility of concentration of two slimes samples from two different plants in operation at the Quadriltero Ferrfero using the column flotation technology without prior desliming. Despite the similarity in terms of mineralogy, grade and particle size distribution, the flotation results indicate a very distinct behavior considering similar process conditions, including variables such as collector type and dosage, depressant dosage, pH and circuit configuration. A final concentrate containing an Fe grade higher than 60%, 4% SiO2 and 3.1% Al2O3 with an Fe recovery up to 75% in rougher column flotation can be obtained from Sample 1 with 45.2% Fe, 28.6% SiO2 and 3.1% Al2O3, when a collector type amide-amine (Flotinor 5530) was used in substitution of a conventional amine collector. On the other hand, it was not possible to obtain a final concentrate containing an Fe grade higher than 55% from Sample 2 with 39.6% Fe, 33.4% SiO2 and 5.1% Al2O3, using both types of collector (amide-amine and amine) even when applying different types of column flotation circuits (rougher or rougher/cleaner). Based on literature review and the results obtained in this study, it can be observed the non-existence of a standard solution for an efficient slimes processing in the iron ore industry. Considering flotation as the most suitable technology for the treatment of such type of material, future research should focus on a deep fundamental study of the collector-depressant mechanism interaction with the iron-bearing and gangue minerals, especially in those ores with a high amount of alumina-containing minerals. Considerations about the effect of bubble generator device to flotation columns and its impact on the metallurgical performance are also discuss regarding to application at industrial scale to slimes concentration.