A study on blended Portland cements containing residual rice husk ash and limestone filler

The cement industry is responsible for large CO2 emissions. Residual rice husk ash (RRHA) can contribute both to a reduction of the environmental impact of cement manufacturing as well as to the agro-energy chain. The objective of this study is to obtain Blended Portland Cement (BPC) with up to 35% substitution of cement by RRHA and limestone filler. On the analysed mixtures, properties required by BPC standards, alkali-silica reaction, and effects of mineralogy and microstructure on BPC properties are discussed. The mixtures satisfy standard BPC requirements and lead to a reduction in CO2 emissions when compared to Portland cement.