Influence of calcium/silica ratio on the formation belite cement clinker from geothermal sludges

Cement industry is seeking alternative raw material and process to reduce the energy consumption and environmental impacts from conventional cement manufacture. This paper describes process of belite cements synthesis. Geothermal sludges, an undesired waste from Dieng Geothermal Power Plant as amorphous silica source and calcium hydroxide were used to form belite cement at elevated temperatures. Experimental results showed that principal phase of belite cement (larnite or β-Ca2SiO4) was formed at temperature as low as 800 ºC. Thus, the geothermal silica is shown to be very promising starting material for the low-temperature production of belite cement. © 2019 Trans Tech Publications Ltd, Switzerland.