2011年9月22日 星期四

Recycling of metals


What will happen to the world if there are no more metals?

If there are no more metals, the world will be backward and all tools will make of wood. The war will never start again unless you have to use wood weapon to fight.
And we use several different metals in our bodies for different functions. Calcium makes our bones stronger, for example, and iron is an important part of hemoglobin, which lets us distribute oxygen throughout our bodies. Potassium is important for providing ions in our central nervous system's electrical circuits and considering the core of the Earth consists of Nickel which is a metal. If there do not have metals, we do not have a planet.
So we cannot live without metal. It is impossible.

Is it important to recycle metal? Thus what are the reasons to recycle metals?

Obviously it makes more sense to make use of available resources, particularly when it is easy to do so, rather than to continually deplete the earth's natural resources. The main environmental benefits involved in recycling metal are as follows:

1.      Save energy, fuel and money

2.      Saves valuable finite natural mineral resources

3.      Reduce greenhouse gas emissions

4.      Reduce pollution of landfill, water and air

5.      Decrease environmental damage caused by mining

6.      Lowers waste

Isn’t it easier to obtain metals through its original form through extraction of metals?

It depends. The metals like sodium, potassium, calcium, magnesium and aluminium are extracted by the process of electrolysis. Highly electro positive metals are extracted by electrolysis.. Metals which are higher in electrochemical series are extracted by electrolysis.
Generally speaking, the method of extraction depends on the metals position in the reactivity series
The reactivity series of metals can be presented to include two non-metals, carbon and hydrogen, to help predict which method could be used to extract the metal.



Ways to recycle

The recycling process for metal is similar to those of other materials. It is best described in four stages:
1.      Collection
2.      Processing
3.      Shredding
4.      Selling




1. Have the delivery company for your new appliance, take the old with them. These companies can either recycle the unit or properly dispose of it

2. Have a professional disassemble your appliance and take the appropriate materials to recyclers in your area

3. If the appliance is still working, sell it on online, donate it to ta charity or give it to a friend.

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