Out of aluminium waste
To reduce natural raw material use, the cement industry is increasingly considering byproducts from other industrial processes such as spent pot liners supplied by the aluminium industry. However, these often need to be refined to adapt them to the demands of the end-product. By Dr Yves C Zimmermann, Regain Services Pty Ltd, Australia.
Figure 1: molar alkali-sulphur balance in Portland cement clinker
Refined byproducts derived from the primary aluminium industry’s spent pot lining (SPL) waste can become a valuable source of fluoride, alkali, alumina and carbon for clinker manufacturing. As a result, significant savings in terms of energy, CO2 emissions, natural raw material consumption and ultimately production costs can be achieved.
