RAW MATERIALS
Fly Ash s the inorganic mineral residue obtained after burning of
coal/lignite in the boilers. Fly Ash is that portion of ash which is
collected from the hoppers of ESP’s and pond ash is collected from the
ash ponds. Bottom ash is that portion of ash which can be collected fro
the bottom portion of the boilers. The characteristics of fly ash depend
upon the quality of lignite/coal and the efficiency of boilers.
India depends upon primarily on coal for the requirement of power
and her power generation is likely to go up from 60,000MW in the year
2010. While generation of power from bituminous sources is on
increase. The generation of fly ash is also likely to increase. The fly ash
generation in India Thermal Stations is likely to shoot up to 170 million
tones in 2010 from the present level of 100 million tones. The disposal of
fly ash in the present method will be a big challenge to environment,
especially when the quantum increases from the present level.
The proposed unite will be using both type of fly ash depends upon the
availbality
MANUFACTURING PROCESS
Fly ash (70%)Lime (10%) Gypsum (5%) and sand(15%) are manually
feed into a pan mixer where water is added to the required proportion for
homogeneous mixing. The proportion of raw material may vary
depending upon quality of raw materials. After mixing, the mixture are
allowed to belt conveyor through feed in to automatic brick making
machine were the bricks are pressed automatically. Than the bricks are
placed on wooden pallets and kept as it is for two days there after
transported to open area where they are water cured for 10 -15 days. The
bricks are sorted and tested before dispatch.
INSPECTION AND QUALITY CONTROL
The Bureau of Indian Standards has formulated and published the
specifications for maintaining quality of product and testing purpose. IS :
12894 :2002. Compressive strength achievable: 60-250 Kg/Cm.Sq. Water
absorption: 5 – 12 %; Density: 1.5 gm/cc Co-efficient of softening
(depending upon water consistency factor) Unlike conventional clay
bricks fly ash bricks have high affinity to cement mortar though it has
smooth surface, due to the crystal growth between brick and the cement
mortar the joint will become stronger and in due course of time it will
become monolithic and the strength will be consistent.
