Armando Corrêa de Araujo

ArcelorMittal · Department of Research & Development

The final disposal of tailings in the form of paste is a technological alternative. The objective of the present study is to obtain knowledge and compare different operational conditions that are favorable to the production of paste with the fine tailings generated after final desliming stage, obtained from the processing of metallic and non-metall...

The interactions of polymers (corn starch, dextrin from maize starch, humic acid sodium salt and sodium carboxymethylcellulose) with iron oxides (hematite and magnetite) have been investigated by measuring adsorption isotherms and by electrophoresis. According to the electrophoresis measurements at pH 7 both iron oxides present negative surface cha...

This article summarises the efforts to reduce the energy consumption in grinding in a magnetite ore beneficiation plant. ArcelorMittal Kryvyi Rih ore beneficiation plant produces magnetite concentrate at 65% Fe and 8% SiO2, of which the D80 is approximately 44µm after three stages of grinding with ball mills and magnetic separation. Characterisatio...

Reverse cationic flotation is the most widely used technique for upgrading iron ore concentrates and has been the subject of many studies in recent years. However, the mineralogical composition of the iron ores previously studied-mostly composed of hematite and quartz, has changed a lot over the years. The iron ore mining industry is increasingly f...

Starch is the most widely used depressant in the reverse cationic flotation of iron ores. There is however, an indication from recent studies, that other polysaccharides may successfully replace them. When starches are used in the flotation of iron ores in the presence of quartz as gangue mineral, their strong adsorption on the surface of iron oxid...

Moisture can be a villain, so new technologies have been explored to make more viable the production of high moisture iron ores. The current work presents the attempt of the utilization of a superabsorbent polymer (SAP) to aid in the screening process and in the ore handling process, such as stockpiles reclaiming and vessels/trains discharge in sub...

Today many types of tailings are generated in the mining operations. Particularly, in the iron ore industry, although 99% of the generated tailings are composed by non-toxic elements, it came into attention especially by the volumes that are being placed into structures as tailings dams. Those structures are expensive and usually have big footprint...

Froth flotation of iron ores is one of the most widely used methods to upgrade iron ore into highgrade concentrates. In recent years, reverse cationic flotation of iron ores has been specifically the subject of several studies. Since quartz is the most common gangue mineral in iron ores, understanding the behaviour of this mineral was the main targ...

In support of the development of its Liberian iron ore project, ArcelorMittal Mining Research and Development (AM Mining R&D) has performed characterisation and beneficiation test work on drill core samples received from the proposed mine area. In addition to this, a sinter feed product was composed by blending and processing the drill cores in ord...

ArcelorMittal is among the largest world’s producers of iron ore. With a geographically diversified portfolio of iron ore and coal assets, it is strategically positioned to serve the network of steel plants, as well as supply the external global market. ArcelorMittal Mining has a global portfolio of 14 iron ore operating units across Brazil, Bosnia...

The Iron Quadrangle district is a world-class iron ore mining district in the region of Belo Horizonte, capital of Minas Gerais state, in Brazil. Many mining companies have been mining high-grade hematite ores for decades throughout the region. The mines reserves often include itabirite ores which are available in high volumes, but have lower iron...

Phosphorus in iron ores is considered as a deleterious component to iron making reflecting in cold shortness of the produced steel. The present study investigates the phosphorus migration pattern resulting from thermal treatment of an oolitic-type iron concentrate with and without additives. To this end focused mineralogical and microscopic observa...

ArcelorMittal is among the largest world’s producers of iron ore. With a geographically-diversified portfolio of iron ore and coal assets, it is strategically positioned to serve the network of steel plants, as well as supply the external global market. While ArcelorMittal steel operations are important customers, the supply to the external market...

Cationic reverse flotation of quartz is largely applied in iron ore in order to concentrate the iron bearing particles. Amine and starch are the most common reagents used as collector and depressant respectively and the selection of those reagents is very important to the definition of the beneficiation route. An iron ore from Liberia, which is com...

The main source of lithium in Brazil is associated with the so-called Eastern Pegmatite Province in the northern region of the Minas Gerais state. Spodumene is the main mineral of lithium that occurs in pegmatites and is frequently associated with the minerals quartz, feldspar and mica. Beneficiation and particularly flotation studies of lithium mi...

ArcelorMittal Liberian deposits are situated in the North of Nimba region, in the North East of Liberia. Only one deposit is nowadays exploited to produce a DSO product (Direct Shipping Ore). The exploitation of other deposits in the area is yet to be defined, but it is expected in a near future. The Liberian iron ore is amenable to produce several...

In a scenario each day more deifier for the mining industry, it’s really necessary to study alternatives witch will optimize several process, decreasing costs. Inside this same context, a great difference is the physical and chemical quality of the ore produced. In Peña Colorada’s case, it was identified that even after several steps of grinding th...

RESUMO Em um cenário cada vez mais desafiador para a indústria mineral, faz-se necessário estudar alternativas que otimizem os desempenhos dos diversos processos, diminuindo seus custos. Dentro deste mesmo contexto, um grande diferenciador é a qualidade química e física do produto final. No caso de Peña Colorada, foi identificado que mesmo após div...

RESUMO A mina de Kryvyi Rih da ArcelorMittal na Ucrânia produz atualmente um concentrado de magnetita com 64 a 66% Fe e aproximadamente 8% de sílica. O alto conteúdo de sílica limita a utilização desse concentrado de minério de ferro. O potencial de enriquecimento desse concentrado por flotação foi portanto investigado. Foi demonstrado que a flotaç...

O presente artigo discute as interferências causadas pelo incremento gradual de umidade nos minérios produzidos atualmente, especialmente aqueles produzidos diretamente para carregamento. O aumento de umidade representa um desafio constante no transporte e tratamento dos materiais produzidos, uma vez que a simplificação dos fluxogramas pode também...

With increasing demand for steel and depletion of high-grade iron ore deposits, more research efforts are being directed toward extending the life of existing ore reserves and developing technology to treat low-grade iron ore resources. Among all the reported technologies, biotechnologies in mineral processing - specifically bioleaching and microbi...

Pellets are the main iron input to the blast furnace at ArcelorMittal Lazaro Cardenas iron and steel making facility in Mexico. Pellets are made at this facility using the concentrates generated and shipped from their captive mines viz., Las Truchas, Pena Colorada, Volcan Sonora. The concentrating plants, after grinding the ore to the liberation si...

The iron ore beneficiation plant at Serra-Azul Mines of ArcelorMittal, Brazil operates at a rated capacity of 3.2 million tons per year. The ore is concentrated using magnetic separation, jigging, hydrocyclones and spiral concentrators. The tailings from the process plant are generated from classifier overflow of 135 tons per hour dry solids and th...

Thickening tailings until they reach a paste-consistency configuration is a process in which many factors are implied. Lab scale work is required prior to studying the feasibility of paste thickening technologies for a given tailing. The global objective is to determine if a representative sample of non-thickened tailings can be engineered at labor...

Beneficiation routes aimed at dephosphorisation of oolitic gravity magnetic concentrate and involving a combination of roasting, re-grinding, magnetic separation and water and acid leaching are investigated. Roasting was carried out at 900 °C for 1 h without or with lime or sodium hydroxide as roasting additives. When additives were used, cement ph...

The presence of relatively moderate quantities of ferromagnetic pyrrhotite in magnetite ores considerably restricts their amenability to conventional magnetite processing techniques employing multiple stages of wet grinding and low intensity magnetic separation. Bench flotation experiments on a skarn-type magnetite ore from Kazakhstan containing 2....

The present study is devoted to improvement of the leaching efficiency during phosphorous removal from high phosphorous gravity-magnetic concentrate. Before leaching the concentrate has been subjected to roasting with the addition of either Ca(OH) 2 or CaO. The oolitic iron ore is roasted at 900°C for one hour. This reflects in reaction between alk...

The reverse apatite flotation with fatty acids has been widely used for the reduction of phosphorus content of magmatic origin iron ores. However, the occurrence of phosphorus intensely disseminated as secondary minerals such as wavellite renders the anionic reverse flotation a challenge. Zeta potential measurements and microflotation tests of wave...

The kaolinite presence in bauxite ores increases caustic soda consumption during the digestion step in the Bayer process. Depending on the kaolinite content, the utilization of the ore in the Bayer process may be unfeasible. This investigation addressed the variables involved in kaolinite flotation through microflotation experiments in a Hallimond...

The oolitic iron ore reserves in Lisakovsky, North Kazakhstan represent quite a challenging deposit both from a technological and from a resource point of view. The diffi culties in processing such types of ore are connected with the extremely fi ne dissemination of phosphorus and gangue minerals inside the oolitic formations. The goethite crystals...

The number of studies addressing kaolinite flotation is steadily increasing, mainly, due to Chinese research contributions. The Chinese bauxites present high amounts of aluminosilicates, for example kaolinite, hindering the application of the Bayer process to the ore. Herein are presented the results of kaolinite microflotation tests with three ami...

The present work presents a study of the characterization and flotation amenability for the concentration of a raw barite sample aiming at achieving concentrates with at least 60% BaO with less than 6,5% of SiO 2. The first procedure was a characterization program of the sample to identify its mineralogical make up and morphology. After that, a stu...

Laboratorial and industrial trials were conducted at Companhia Siderurgica Nacional (CSN), Casa de Pedra mine, using a novel co-depressant developed by Georgia-Pacific (GPR-855), in association with corn starch, as depressant. Bench flotation experiments were performed partially replacing starch by GPR-855. The best results were achieved with 30% r...

Apatite flotation presents considerable challenges related to selectivity, especially when one takes into consideration the rather loose structure of this family of minerals and the several possible substitutions in its lattice. Hence, the state of dispersion of apatite gains considerable relevance when flotation is considered. The present work des...

Studies on kaolinite flotation are being driven by Chinese bauxite characteristics, presenting low alumina:silica weight ratios. This paper addresses the effect of the presence of cetyl pyridine chloride (CPC) and cetyl trimethyl ammonium bromide (CTAB) on kaolinite floatability and zeta potential. The reagents were dosed at three concentrations an...

In the last years, the disposal of tailings in the form of pastes and/or high-density slurries has gained importance as it may present significant advantages in comparison to more traditional disposal techniques. The knowledge of physical chemical characteristics of the material to be disposed, as well as the interactions that result from the use o...

Phosphorous occurs in complex associations on sedimentary and meta-sedimentary iron ore deposits, mostly associated to the iron oxides/hydroxides crystal structures. The fluids generated during the weathering of these deposits may release phosphorous and several other elements into solution. After the dissolution of apatite, the released phosphorus...

The main purpose of this work is to describe the experience obtained from laboratorial, pilot plant and industrial test runs of cationic reverse flotation of iron ores in the presence of both amine and frothers. Enhanced iron recovery is the main gain obtained from the synergic interaction of amines and frothers when jointly applied for the flotati...

The present work describes the effect of combining depressants to enhance selectivity and recovery in the reverse cationic flotation of iron ores. Cationic reverse flotation of iron ores employs starches and their derivatives as selective depressants during the amine flotation of quartz at alkaline pH conditions. A novel polymeric depressant added...

Iron ore concentration through flotation represents an important application of chemicals in minerals processing. Selective separation between iron oxides and siliceous gangue minerals can only be achieved, in most cases, through the proper application of depressants, pH modifiers and collectors. The purpose of the present work is to describe the u...

A mineral paste can be defined as a colloidal system presenting characteristics of homogeneous fluid in which no particle size segregation takes place and, when water does not exudate from the paste. The objective of this work is to determine the rheological characteristics of paste mineral systems prepared from iron ore flotation tailings and slim...

Only a small number of mineral processing plants currently dispose tailings as pastes in Latin America. Most plants, inclusive of all iron ore beneficiation facilities, utilizes conventional sub-aqueous disposal of tailing on the basins of tailings dams. This is the case in Chile as well as in Brazil. Several advantages of paste disposal in compari...

Iron ore concentration through flotation represents an important application of chemicals in minerals processing. Selective separation between iron oxides and siliceous gangue minerals can only be achieved, in most cases, through the proper application of depressants, pH modifiers and collectors. The purpose of the present work is to describe the u...