we are facing a problem with high free lime although the lsf is quite low 94-95 in clinker and the kiln is hot enough.
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Belite
There could be a number of reasons of which the most common probably are too coarse raw meal (combinability) or early formation of clinker "balls" with high free lime in the core.
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Raj Sahu
A decrease of one of the following parameters will decrease the free lime by approximately 1% at 1400 degree centigrade (This is only strictly correct if it were possible to change one parameter without affecting the others):
Decrease of:
0.5 Silica Modulus or,
2% Coarse Calcite +125 micron or,
1% Coarse Quartz +45 micron,
will decrease clinker free lime by 1% total at 1400 degree centigrade.
Finer grinding will help to reduce Coarse Calcite minerals.
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I.Flex
thank you and i think it's realy related to the high sieve of the raw meal.