i was just wondering how iron ores were formed and how those ores change to iron?
Iron ore is just a rock -- in fact it would probably be hard to tell iron ore from a piece you found lying out in your backyard. It's what mines produce, and it needs to be burned to separate it into its different elements. Iron is an element. It is the purest form of the metal. Steel is mostly iron, but it is not pure iron. To make steel you must burn coke (another kind of rock) along with the iron ore. The coke adds carbon to the iron, producing steel which is stronger than pure iron.
Many of the world's large iron ore deposits were formed early in the pre-cambrian era; when there was no free oxygen in the atmosphere. It is thought that the action of bacteria in the oceans produced oxygen; which combined with the dissolved iron minerals in the water to form iron oxide; which precipirated out and fell to the bottom. These formed a particular type of roock called Banded Iron Formation; a mix of iron oxide and silica. Very much later, these deposits were altered by circulating waters, which concentrated the iron, and leached out the silica; forming the rich iron ores we have today. To extract the iron; the rock is first crushed and treated to remove as much unwanted material as possible; sometimes being pelletised for easier transport. The ore is then a mix of iron oxide and some silica, with small amounts of other minerals. The ore is placed in a blast furnace together with coke and limestone. When hot air is blown through the mixture, the coke burns and combines with the oxygen to form carbon dioxide, leaving molten iron. The limestone reacts with the non-iron minerals to produce slag, which is lighter, and floats to the surface. The iron can then be drawn off as 'pig iron'; but needs further treatment before it can be used or alloyed with other materials to make steel. There are good articles about iron ore and banded iron in pedia
Iron is the most widely used. Iron ore is mainly used for iron and steel industry, smelting iron and steel according to the different carbon content. The so-called iron ore deposits are the main target of industrial development and utilization. Iron ore beneficiation plant is generally divided into several stages, crushing, grinding, classification and separating. How can we design our iron ore processing plant? Maybe a professional manufacturer and supplier is one of the best choices. Before we talk about designing of iron ore processing plant, we need learn the working flow of iron ore processing first. Raw iron ore will be sent to primary crushing equipment first. In primary crushing equipment, we can crush them into small particles. After primary crushing, the secondary and tertiary crushing equipment will crush iron ores into the finesse size which is below 12mm.
