4 posts
TimePosted 07/10/2016 09:36:05
K.B says

Alite polymorphs

Dear all,

Most of clinker alite crystals are of the monoclic phase, as either M1 or M3.

1. My first question is which one is really the most reactive? Indeed, there are those who say alite rich in M1 polymorph is desirable to easy grind the clinker and this is maybe why some say that alite M1 is considered more reactive. But I also heard that  it is not really proven that alite M1 is more reactive than the alite M3. 

2. My second question concerns the influence of SO3 and MgO. Is it always true that an increase in SO3 in the clinker favours M1 and an increase in MgO favours M3? 

3. I heard that the C3A content in the matrix influences the ratio M1/M3. May I know why? It is because impurities in alite crystals? Suppose there is an increase in C3A content, whichever alite M1 or alite M3 will be predominant?

4. I read in the litterature that with slow initial cooling it might form too much M3. But with slow precooling at the kiln exit (a long black plume for example), there should be a partial reversible transformation from alite M3 to alite M1 thus leading to an increase in alite M1 and not in alite M3. Am I right?

5. What if you have a long burning time in the sintering zone on considering bigger alite crystals formation? Impurities in alite is less but what about the ratio M1/M3, does it remain constant? Does favor more alite M1 or alite M3? Or does it depend on the maximum temperature of alite formation?

Kind Regards,


Know the answer to this question? Join the community and register for a free guest account to post a reply.