Monday, May 20, 2013


The Human physical body is composed of “Saptadhatus”.“Saptadhatus” is a Sanskrit word, which means seven constituent elements (Sapta=seven, dhatus=elements).As the human body, the physical world also composed up of some Elements(dhatu) and Minerals ,which gives rise to many lives from a unicellular to multicellular organism . We named it as ‘Earth’. The whole animal and plant kingdom is being nurtured by it .Hence we call it as “Mother Earth”. With the sand dunes of time the human civilization has been regarded by the use of metals, from the stone age to bronze age, iron age, gold age and now we call this age as the age of Aluminium.
On the year 1808, Sir Humpry Davy identified the existence of metal base of alum, which he first termed as alumium and later as aluminum.
Since then, Aluminium has been remained as a key metal for many scientist and chemists  to produce it in a cost effective way for day to day use. Later on the year 1887 a Austrian chemist Carl Josef Bayer invented the cost effective way to produce Aluminium from Bauxite. The process began to gain importance in metallurgy together with the invention of the electrolytic Aluminium process invented in 1886. Together with the cyanidation process invented in 1887, the Bayer process marks the birth of the modern field of hydrometallurgy.
Today, the process is virtually unchanged, succeeding by Hall-Herault process for smelting and it produces nearly all the world's alumina supply as an intermediate in aluminium production.

Bauxite is the ore of Aluminium. For a tribe aluminium is his blood and some soil. For a Metallurgist it is some bauxite and current, for a businessman a handful of dollar and a luxury car, for the consumer society it a wrapper of a tobacco and insulator of a medicine. For the students who are studying in D.P.E.P schools it is the utensils of a common man, for the imperialistic nations like USA and Britain it is supersonic fighter planes and deadly weapons.
The environmental impacts of aluminium production.
To produce Aluminium products from Bauxite, the following 4 processes are necessary
 Mining – To extract raw Bauxite from the earth
 Refining – To refine raw Bauxite into Alumina powder
 Smelting – To convert Alumina into liquid Aluminium
 Casting – To produce Ingots, Wire-rods and Billets from liquid Aluminium

To produce one ton aluminium around 5 to 6 ton bauxite(grade) , 8 to 10 ton water , 1.5 ton coal , 0.6 ton anode carbon, 0.25 ton fuel, 0.2 ton caustc soda, 0.1 ton fluride salt, o.r ton calcin and petroleum, 0.15 ton of coke or pitch and 15000-16000 KW current.
Every one ton aluminium discharges 18 ton of poisonous wastes. From each ton of aluminium 6 ton red mud(a mixture  of sodium aluminate and undissolved bauxite residues containing iron, silicon, and titanium,14 rare earth elements,& some radioactive elements like HF,U,Th etc.),which contains  50 k.g of deadly poison called as Spent Pot lining(SPL) and many other cancer causing harmful agents like cyanides, heavy meatals etc.
Mining Bauxite causes many environmental hazards then any other mineral explorations, though  Aluminium is mainly produced from bauxite and over 90% of the world’s bauxite resources are concentrated on the tropical and sub-tropical belt in Australia, Guinea, Jamaica, Surinam, Brazil, and India(Odisha shares the highest 55% Bauxite reserve). It totally stops the perennial water streams and reduces the ground water level causing the area totally infertile and barren. The bauxite dusts which produce during mining excavations and conveying can travel up to 15 to 20 km on air and can contaminate the air and water so critically that  to cause a desert like surrounding.The aluminium refinery needs minimum 4 to 5 ton of water for refining.If the refinery runs a thermal power plant then it produces tons of  fly ash which ll be later collected on a ash pond and it emits a tons of carbon dioxide to the environment.Smelting plant emits many HFCs(Hydro floro carbons) like CF4, Hexafluoroethane which are the main substance for Ozone layer depletion and global worming.

Keeping on view of the above facts, mining Bauxite is no less hazardous than any nuclear disasters. While we are only busy on focusing on the nuclear disasters ignoring this mining activity, which might create another human made catastrophe and can turn this blue planet like  Mars.

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