Fly
ash, Lime calcined gypsum and sand, with requisite quantity of
Water
is mixed in proper proportions which produces slow setting
Cement,
the resultant mass pressed is in to bricks of any desired strength. These bricks
can be used in building constructional activities instead of common burnt clay
bricks. These bricks are lighter in weight and stronger than common burnt clay
bricks. The generation of fly ash in India by thermal power stations is
more than 100 million tones per annum (in December 2010). One kilogram of coal
of fired yields fly ash ranging from 200 to 500 grams. At present only 6% fly
ash being utilized.
180 billion tones of common burnt clay bricks are consumed annually.
Approximately 340 billion tones of clay – about 5000 acres of top layer of soil
dug out for bricks manufacture. Soil erosion, and emission from coal
burning or fire woods which causes deforestation are the serious problems posed
by brick industry. The above problems can be reduced some extent by using fly
ash bricks in dwelling units.
Demand
for dwelling units likely to rise to 80 million units by
year
2015 for lower middle and low income groups, involving an
Estimated
investment of $670 billion, according to the Associated
Chamber
of Commerce and Industry (Assocha). Demand for dwelling
units
will further grow to 90 million by 2020, which would requires a
minimum
investment of $890 billion. The Indian housing sector at
present
faces a shortage of 20 million dwelling units for its lower middle and low
income groups which will witness a spurt of about 22.5 million dwelling, units
by the end of Tenth plan period. There is ample scope for fly ash brick and
block units.
So by using this type of
bricks we not only conserve our environment from degradation, also made a
positive step to preserve our precious top soils.