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.
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.