HIGH FREE CAO.....

friends on this clinker chemistry our free lime is very high so now wat to do.....

SIO2           22.14

AL203         6.41

CAO           3.20

MGO           1.82

SO3             0.41

NA2O          0.05

K2O            0.63

LSF            90.40

SM             2.30

AM             1.99

Liquid phase  28.80

C3S              49.29

C2S              26.28

C3A               11.58

C4AF             9.75

LITR WT       1280

 FREE CAO    3.36%

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Re: HIGH FREE CAO.....

Dear Mr. Armankhan,

Your given clinker specification is not correct, please recheck. The problem of high free lime is due to process only. Sending my calculated clinker composition as per your specification.

Vikpro

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Re: HIGH FREE CAO.....

Hello Armankhan,

Yes, as Vikpro pointed out, you made an error in typing your clinker analysis results. I assumed that the 3.2% for CaO was actually Fe2O3 and then calculated the CaO from your LSF of 90.4 and got the following corrected analysis;-

From this, I can't see any chemical reason why you should be getting such a high free lime, as long as the raw meal is ground fine enough and you don't have too much coarse silica and/or calcite.

I have a couple of questions;-

What is your raw meal residue on +212um and +90um (or equivalent) sieve?

Have you ever checked your raw meal for coarse silica (>32um) and coarse calcite (>90um)?

What is your hot meal (ex bottom cyclone) SO3 content? (average value and range)

Is the free lime consistently >3% or intermittently very high then low?

Do you have buildups/slabs regularly falling into the kiln?

Do you measure your burning zone temperature? If so, what is the average value and typical range?

Regards,

Ted.

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