Iron is the most commonly used metal, especially the highest percentage of metal on the earth, the earth’s outer core and the kernel of the main ingredients, is high crustal abundance on the fourth element. Iron is a chemical element, which chemical symbol is Fe, its atomic number is 26. It is a kind of transition metals. Iron is a shiny silver metal, hard and malleable, melting point is 1538 ℃, boiling point is 2750 ℃, have very strong ferromagnetic, and good plasticity and thermal conductivity. The crystal structure of body centered cubic structure, lattice constant a = 2.87 Mr.
Iron usually contains carbon in everyday life ,which lead to electrochemical corrosion when it exposure to oxygen and encounter water.and easy exposure to oxygen in water under the condition of , and high purity iron law is not easy be corrosiones.In theory, any mineral contain iron or iron compounds can be referred to as the iron ore. However, in industry or business, the iron ore not only have contain iron, but also must have a use value.
Existing in the nature of iron minerals can be used as raw material for ironmaking. There are mainly magnetite, hematite, limonite and siderite, etc. Natural iron ore after crushing, grinding, magnetic separation, flotation, re-election and other procedures gradually selected out the iron.
Iron ore is often divided into rich ore (iron mass fraction is higher than 50%) and lean ore (iron mass fraction below 45% ~ 50% by the iron it contains. When assessing the grade and quality of iron ore , in addition to see beyond the iron content of the iron ore, we also need to look at its gangue composition and the harmful impurities (like sulfur, phosphorus) it contains.
The world’s iron ore resources concentrated in Australia, Brazil, Russia, Ukraine, kazakhstan, India, the United States, Canada, South Africa and other countries.
The world’s 10 largest iron ore produceThe annual output (thousands of metric tons)
In daily life, iron can be regarded as the cheapest ,the most useful,the most abundant,and the most important metals. Iron is the most important industrial material and agricultural production.It is the basic structure of materials, and ferroalloy have a widely use in our life . such as national defence and war need iron , construction and production need iron ,and even the steel production capacity is a represents of the modernization level of a country.
For human body, iron is an indispensable trace elements. In the ten kinds of essential trace elements, iron both on the importance and the number is in the first place. A normal adult body contains more than 3 grams of iron, equivalent to the quality of a small nails. Hemoglobin in the blood of the human body is iron complexes, which has the function of fixed oxygen and oxygen. The human body lack of iron can cause anemia. As long as you are not a partial eclipse, not bleeding, adults usually does not lead to iron deficiency.
The so-called gas poisoning (carbon monoxide poisoning), is also due to the heme iron ion on the connection of oxygen originally occupied by a carbon monoxide, which lesd to the heme lost the ability to absorb oxygen,and then make the person suffocate poisoning and death.
The iron is also a indispensable catalyst for plant to make chlorophyll. If a potted plant is lacked of iron, the flowers will lose their color and aroma, also turns the leaves yellow and wilt. Usually soil also contains a lot of iron.