Iron ores occur in igneous, metamorphic (transformed), or sedimentary rocks in a variety of geologic environments. Most are sedimentary, but many have been changed by weathering, and so their precise origin is difficult to determine. The most widely distributed iron-bearing minerals are oxides, and iron ores consist mainly of hematite, which is red; magnetite, which is black; limonite or bog-iron ore, which is brown; and siderite, which is pale brown. Hematite and magnetite are by far the most common types of ore. The upgraded ore, or concentrate, is in the form of a very fine powder that is physically unsuitable for blast furnace use. It has a much smaller particle size than ore fines and cannot be agglomerated by sintering.
Iron Ore Bluedust
Mineralogical observations indicate that the Blue Dust is mainly composed of haematite, martite and goethite while quartz and kaolinite are the gangue minerals. Silica removal is the primary control of iron enrichment. Geochemical and field observations indicate that the Blue Dust in these deposits is regarded to be of supergene-modified hydrothermal origin. In the first stage, the early hydrothermal process affects the primary unaltered Banded Iron Formation by simultaneously oxidising magnetite to martite and replacing quartz with hydrous iron oxides. In the second stage, the supergene processes upgrade the hydrous iron oxides to fine grain microplaty haematite. The supergene process causes the leaching of remnant silica from hydrothermally upgraded iron ore under a suitable Eh and pH condition and leads to the formation of Blue Dust.
Iron Ore Fine
Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the form of magnetite, hematite, goethite, limonite, or siderite. Lower-grade sources of iron ore generally require beneficiation, using techniques like crushing, milling, gravity or heavy media separation, screening, and silica froth flotation to improve the concentration of the ore and remove impurities. The results, high-quality fine ore powders, are known as fines.
Iron Ore Lumps
As-mined iron ore contains lumps of varying size, the biggest being more than 1 metre (40 inches) across and the smallest about 1 millimetre (0.04 inch). The blast furnace, however, requires lumps between 7 and 25 millimetres, so the ore must be crushed to reduce the maximum particle size. Crushed ore is divided into various fractions by passing it over sieves through which undersized material falls. In this way, lump or rubble ore (7 to 25 millimetres in size) is separated from the fines (less than 7 millimetres). If the lump ore is of the appropriate quality, it can be charged to the blast furnace without any further processing. Fines, however, must first be agglomerated, which means reforming them into lumps of suitable size by a process called sintering.
The supplies of india mill scale are from small & medium sized steel, one month about 50 - 500 tons quantity per month.Our Company has a long term good relationship with India major exporters in mill scale and iron ore business which could gurantee the stable quality, quatity and cargo competitive price. Current allotments of materials are available in volumes of 10 to 20 k tons per month. Spot purchases or potential long term contracts are our specialty. All material we sell is produced in the India, is screened clean, low residuals and will meet most standard specification needs. These materials are a very good material for use in steel making.In India many factories mix a certain amount of this material with their iron ore fines before they are sintered to help boost the iron content. We can supply quality single source, low residual mill scale for use in the Petro Refining, Cement Manufacturing, Counterweights and Sinter Plant Feed-stock.
What is Mill Scale?
Mill scale is basically the rust coating which forms on the poured steel or newly cast surface.The material appears flaky and can be seen easily on the red hot surface. The materials are produced on the plates outer surface, profiles or sheets. Production starts by rolling the steel billets and hot iron in steel rolling mills.
Is mill scale hazardous?
Mill scale is not generally hazardous. Oily mill scale is not immediately hazardous as well but long term exposure to oil can potentially be harmful. Standard precautions advised, gloves and eye protection.
What are Mill Scale Prices?
Mill scale prices change with the scrap, ore and steel markets. Mill scale is generally sold under yearly bids or spot purchases. There are services that provide current mill scale pricing.
Bauxite is a sedimentary rock with a relatively high aluminium content. It is the world's main source of aluminium and gallium. Bauxite consists mostly of the aluminium minerals gibbsite, boehmite and diaspore, mixed with the two iron oxides goethite and haematite, the aluminium clay mineral kaolinite and small amounts of anatase and ilmenite. Bauxite is usually strip mined because it is almost always found near the surface of the terrain, with little or no overburden. Bauxite rocks are typically classified according to their intended commercial application: metallurgical, abrasive, cement, chemical, and refractory. Usually, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution at a temperature of 150 to 200 °C (300 to 390 °F). At these temperatures, the aluminium is dissolved as sodium aluminate (the Bayer process).
Manganese ore is required in iron making to control the manganese content of the hot metal in the desired range. Unlike other plants, where manganese ore lump is used directly in blast furnace, in VSP, it was proposed to use manganese ore fines in sinter productions. This would ensure much more consistent manganese content in the hot metal. Manganese ores contain manganese in various oxide forms ranging from MnO2, Mn2O3, Mn3O4, to MnO. Manganese oxides higher than MnO are unstable and decompose to MnO in the presence of CO below the smelting temperature, and MnO is reduced by carbon at the smelting temperature. The behavior of manganese oxides higher than MnO affects the efficiency of the smelting operation. Their contents in ores are quantified by the concept of available oxygen, which is defined as the oxygen content in excess of that of MnO.