DEAR TED
I HAVE 0.4 TO 0.5% TITANIA IN MY RAW MIX ALONG WITH OTHER OXIDES .
MY QUESTION IS DOES TITANIA HELPS IN LIQUID % , IT'S VISCOSITY , COATING INSIDE KILN, CLINKER QUALITY , BURNABILITY ETC.
IN THE LIQUID % CALCULATION FORMULA IS THERE ANY FACTOR TO INCORPORATE FOR TITANIA OR OTHER SIMILAR OXIDES?
DOES THE AMOUNT OF TITANIA IN RAW MIX REPLACES SOME AMOUNT OF ALUMINA/IRON OR BOTH?
PLEASE DO REPLY.
THANKS
SIDHANT
Hello Sidhant,
TiO2 is present in all clinker phases, expecially ferrite (C4AF) in which it has a maximum solubility of 18% (compared to only about 1 or 2 % in the other clinker phases). Therefore it certainly contributes to the liquid phase, but I am not aware of any liquid phase formula that takes TiO2 into account. However, since it substitutes for iron you could probably use the following formula;-
% Liquid Phase (1450 Deg.C) = 3.0*Al2O3 +2.25*(Fe2O3 + TiO2) +MgO +K2O + Na2O +SO3
1% TiO2 in clinker also promotes clinkerisation and lowers the temperature at which the liquid phase first appears by about 50-100 Deg.C. It also activates alite and therefore increases cement 3-90day strengths at the same concentration. Hence TiO2 encourages
better burnability.
Colour is considered to be darker when TiO2 is present in the ferrite phase.
Although TiO2 enhances the hydraulic reactivity of alite and improves strengths, it also retards setting time, so it is not recommended that TiO2 levels exceed about 1% in clinker.
Titanium (+4) substitutes for iron (+3) in ferrite, the freed Fe2O3 can then consume additional CaO and Al2O3 to form more ferrite, effectively increasing the amount of ferrite present.
Hope this helps...
Regards,
Ted.
I would also like to add further to the response of MrTed,
A higher Ti:
1.Results in sharp redction in C3S content with equal gain in C2S content and appreciable variations in other phases.
2.Reduce viscosity and surface tension of the melt
3.Reduces grain size of alite and belite
4.Causes slower setting and lower early strength
5.Forms darker colour clinker