About Rice Husk Ash
milling industry generates a lot of rice husk during milling of paddy which
comes from the fields. This rice husk is mostly used as a fuel in the boilers
for processing of paddy. Rice husk is also used as a fuel for power generation.
Rice husk ash (RHA) is about 25% by weight of rice husk when burnt in boilers.
It is estimated that about 70 million tones of RHA is produced annually
worldwide. This RHA is a great environment threat causing damage to the land and
the surrounding area in which it is dumped.
During milling of paddy about 78 % of weight is received as rice , broken
rice and bran .Rest 22 % of the weight of paddy is received as husk . This husk
is used as fuel in the rice mills to generate steam for the parboiling process .
This husk contains about 75 % organic volatile matter and the balance 25 % of
the weight of this husk is converted into ash during the firing process , is
known as rice husk ash ( RHA ). This RHA in turn contains around 85 % - 90 %
So for every 1000 kgs of paddy milled , about 220 kgs ( 22 % ) of husk is
produced , and when this husk is burnt in the boilers , about 55 kgs ( 25 % ) of
RHA is generated.