1. Modified Bauxite Residue as an Alternative Supplementary Cementitious Material
Pithchai Sivakumar
KU Leuven (Belgium)

2. Current scenario Possible alternative
Cement industry = 8 to 10 % of global CO2 emission, to 5 billions tonnes of cement production
Alumina industry = 150 to 180 millions tonnes of bauxite residue
Possible alternative
Can we use bauxite residue in cement industry?
Yes! As a SCM after modification
Faculty of Engineering Science, Department of Materials Engineering

3. Experimental procedure
81.5% BR
9.25% SiO2
9.25% B2O3
Thermodynamic calculation
64 wt% liquid
36 wt% hematite
1 h
1200 °C
Quenching
BR Slag mortar
40% (BR Slag) + 60% (OPC)+ Sand + Water
“BR Slag”
Faculty of Engineering Science, Department of Materials Engineering

4. Results and discussion
Characterisation of BR slag
“BR Slag”
Amorphous
(Ti, Al) Hematite
Component
Al2O3
SiO2
B2O3
CaO
Fe2O3
TiO2
Na2O
wt% 28 26 14 11 8 6 3
Composition of amorphous phase (mass balance)
Faculty of Engineering Science, Department of Materials Engineering

5. Compressive strength Conclusion “BR Slag mortar”
Use of B2O3 and SiO2 as fluxing admixtures in a thermal process.
BR slag mortar: compressive strength = 66 MPa after 28 d, exceeding the OPC.
Process contributes to minimising the volume of disposed BR.
Faculty of Engineering Science, Department of Materials Engineering

6. Thank you...