Good job bringing this to light. People won't realise how huge the problem is and municipalities are woefully ill equipped to...
Agreed; mining can never be sustainable, but then how do you get the metals to make all the things you need in the course of...
Very good piece.
ONCE Upon a time, potters eked out
a comfortable living by producing
earthen wares. Today, not too many
people use their products and their
market has shrunk considerably.
Besides, they have to buy firewood at
exorbitant rates, while, earlier they
collected the same from nearby forests.
These two factors have made them
the most economically backward
community in the country.
Traditional kilns in Orissa use 1.2 kg
of firewood for sintering (blending a
mixture into a solid mass by heating)
each kg of thin-section pottery
like earthen pots and two to three kg
for making roof tiles. Sintering is
conducted at a low temperature of
600'C. Hence, the products are poor in
strength and have a short life. Also, temperature gradient in traditional kilns is
not uniform with the result that 10 to 20
per cent of pots are rejected after every
firing. due to under-or over-heating
or breakage. Traditional kilns also
release a lot of smoke, thus polluting the
environment. After firing, they are tom
down and reconstructed to enable
unloading- of the sintered pottery and
loading of unbaked pottery, thus
increasing labour costs.
In -an effort to counter these
problems, the Bhubaneshwar-based
Regional Research Laboratory has
developed a low cost pottery kiln named
'Queen'. The 'Queen' kiln is bottle-shaped with the chimney at the place
of the mouth. It uses low-grade raw
coal to bake products like domestic
earthen ware, handicrafts, roof tiles,
floor tiles, etc.
The 'Queen', a permanent structure
made of red bricks, clay and sand,
has been in operation in Orissa and
West Bengal for the past two years.
The pottery is loaded and unloaded
through a door, cutting down drastically on labour. The On design ensures
an uniform high temperature of
800-900'c during baking, which reduces
loss due to breakage and also increases
the life and strength of the products.
Firing time is also reduced in the
'Queen', which takes a total of seven to
12 hours depending on the moisture
content of the pottery, while traditional
biomass kilns take up to
48 hours. For firing
Y one kg of pottery, 125-
175 gm of F-grade coal
is utilised thus saving
60 per cent energy. The
pollution caused by the
kiln is minimal as the
coal is totally burnt. By
switching over from
kilns to traditional
'Queen' kiln, the overall
cost of production goes
down by 50 per cent.
the size, the construction costs of these kilns
range from Rs 6,000
to Rs 18,000 in rural
areas. The average life
of the kilns is five to 10
years depending on the