Manufacture Of Iron By Blast Furnace Process
Iron is a naturally occurring element in its ore form (Haematite),
however for iron to be of any use the impurities must be removed. This
is done by a process involving a blast furnace. Extremely high
temperature in the range of 870°C are reached within the blast furnace
and this heat causes reactions to occur within the blast furnace that
remove some of the impurities from the iron ore. The materials placed
in the blast furnace are iron ore, coke and limestone. Coke is the
reducing agent [substance that causes the substance it is reacting
with to be reduced and in turn is oxidised], when hot air is blasted
into the furnace it reacts with the coke to form carbon monoxide, this
carbon monoxide then goes on to react with the iron oxides which are
present in the iron ore to reduce [removal of oxygen from a substance]
the oxides to metallic iron. The limestone is simply present to react
with the impurities removed from the ore forming calcium silicate.
Without the limestone Iron Silicate would form therefore reducing the
yield of metallic iron. The Calcium Silicate and other impurities sit
on top of the molten metallic iron forming a layer known as slag.
Therefore the metallic iron can be tapped off and removed for further
refining.
Below is a diagram of a blast furnace you can see at the top the
reactants are fed into the blast furnace and at the bottom the molten
iron is being tapped off and taken away in carriages.
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There is a lot of waste products in the layer of slag that is formed
when the process of obtaining molten iron is carried out. The table
below shows the usual composition of slag showing the different waste
products created:
Name of Compound
Symbol of compound
Percentage Composition
Calcium oxide
CaO
38%
Silicon dioxide
SiO2
36%
Alumina
Al2O 3
12%
Iron is a trace element, which is a group of minerals present in small quantities in the body. Other trace elements include copper, zinc, selenium, manganese and iodine. These minerals cannot be synthesized by the body and must therefore be supplied in the diet. Iron is the most common trace element in the human body; adult males have approximately 3.5 g iron in total, or 50 mg per kg body weight while females have about 2g total iron or 35 mg per kg bodyweight. Iron can exist in oxidation states from -2 to +6, but mainly exists in the ferrous (+2) and ferric (+3) states in biological systems. As iron has the ability to accept and donate electrons readily, it can interconvert between these two forms with ease. Thus, iron can participate in
For over half a century the Pittsburgh region was the largest concentration of steel making in the world. Its collapse was spectacular. The mill towns strung along the Monongahela Valley have now suffered forty years of decline. Much of their shabby infrastructure and buildings (at best homely even in their prime) has decayed, most of their population has fled to the metropolitan suburbs or left the region, and those that remain, for the most part poor, struggle or live off memories. Regeneration is a continuing problem for public policy makers as the mill towns struggle on life-support systems — public welfare for individual households; funding from federal, state and local agencies for public services, projects and a plethora of `initiatives´. Re-born they are not.
...d deep in the earth) or poisons gas, and collapses were not uncommon. In an attempt to avoid these issues they set up ventilation and had young children called trappers open and close them so coal trucks could pass through. They also deemed it would protect the rest of the coal if an explosion were to occur. But convenient inventions were soon devised; the air pump (1807 john bundle) and the safety lamp (1815 sir Humphrey Davy).The air pump was used to move poisonous or explosive gases and the safety lamp prevented explosions too by encoding the candle in a barrier of glass and metal. Despite all the safety changes the mine still remained immensely dangerous. Coal mines were especially inhumane to children some trappers were employed as young as five and were expected to carry bundles of coal much too heavy for them which caused many deformities in the children.
Iron comes from the Latin word ferrum. From ferrum its symbol became Fe. The atomic number of iron is 26, and its atomic weight is 55.845. Iron is a magnetic, bendable, shiny white metallic element.
The crucible and cover were placed on the triangle, and they were heated until they turned red hot. Afterwards, they were removed from the fire with the tongs and placed on the wire gauze to cool for ten minutes. Then, the mass of the crucible and cover was measured and recorded in the data
In the early part of this century was a time when industry was booming with growth around the installation of major railroads. With this growth came the transatlantic cable, the telegraph, and a whole lot of steel. Steel would be needed in the construction of these new transportation systems and communications were now possible between businesses and industries. (Wren, 2005)
This waste should not be pressured upon a geographical area if they do not create it. A clean and healthy environment is the only thing many lesser-developed countries have to cherish.
Solid waste can be classified as all waste materials except hazardous waste, liquid waste and atmospheric emissions (Liu & Liptak, 2000). The world consumption of non- renewable sources of energy as raw materials are predominantly getting depleted and on the contrary waste produced is increasing massively, solid waste is one of the major problems faced by the world and the construction industry today. In New Zealand, construction and demolition waste produced constitutes a high percentage of the total solid waste produced in the country. The Ministry for Environment reports around 1 million tonnes of construction and demolition waste goes to landfills each year and about 40% of that originates from residential construction.
Literally let’s talk trash, even in an environmental conscience society no one really wants to talk about how they dispose of their garbage and whether they recycle or not. Regardless, the next time you throw something in the trash bin, stop and consider where well your garbage end up, most likely in an over-crowded landfill. According to estimated statistic taken in 2006 “55% (percent) of our waste will be buried in landfills, 33% (percent) will get recycled, and 12% (percent) will be burned in incinerators” (Human Footprint). Our garbage, whether it is buried, burned, or dumped is something that should concern every one of us. Consequently most landfills constructed in the early 1930’s were not properly designed to prevent leakage. Therefore lechate a toxic liquid created from waste has been known to percolate into the air, contaminate the ground water and infiltrating the soil which will ultimately affect our health and environment. Unfortunately, for our own health and environment once our garbage is out of sight it is also out of mind.
Waste incineration units produce a lot of carbon dioxide gas approximately around one third of the greenhouse gasses. It also impacts people’s health as they get exposed to the toxic emissions by breathing in the air or consuming contaminated food and water. Additionally, when the garbage gets burnt by the incinerators they end up as ashes which are then emitted from the chimneys, including the toxic materials and end up in specialist landfill sites for hazardous waste.
In order to achieve different levels of contaminant removal, individual waste-water treatment procedures are combined into a variety of systems, classified as primary, secondary, and tertiary waste-water treatment. More rigorous treatment of waste-water includes the removal of specific contaminants as well as the removal and control of nutrients. Natural systems are also used for the treatment of waste-water in land-based applications. Sludge resulting from waste-water treatment operations is treated by various methods in order to reduce its water and organic content and make it suitable for final disposal and reuse.
Solid waste can be classified in different types, depending on their source, household waste is generally classified as municipal waste; industrial waste as hazardous waste or hospital waste as infections waste. It quite obvious that South Africa environment is deteriorated by the illegal dumping area that around here. Solid waste is a major problem this country is facing at the moment. The province that is experience this major problem is Gauteng province, this an urban area am taking about, and since it’s clear that over population is the cause of the problem. Gauteng province is an over populated than rural area .solid waste pollution is refuse or garbage that people use in their everyday life in their house, such as plastic
Left behind are tailings, which are large piles of crushed rock left over when minerals have been extracted from rocks that once contained them. These tailings are then left prone to wind dispersion and water erosion. This wind dispersion occurs since the sand-like tailings are easily swept up by the atmosphere by wind and spread throughout the environment as dust particles. Figure 1 shows the wind erosion of a mine tailings pile being blow up into the air, creating dust. These tailings contain metal contaminants like arsenic, lead, and cadmium, which creates a problem for the environment and they can persist for decades due to the low pH levels and can cause problems in soil stabilization (arizona.edu, 2008).
All organic solvents, soluble organic waste and as well as paraffin is disposed by incineration. Other miner wastes and controlled waste materials are collected into bins and then disposed later by using proper procedure.