The fly ashes produced in Australian power stations are light to mid-grey in colour and tend to resemble the appearance of cement powder. They exhibit a range of values in their physical and chemical properties. These are determined by the interaction of a variety of factors, principally the coal type, coal source, minerals and primary elements present in the coal, furnace type, plant age and the specific combustion conditions experienced by the coal.
The particles in FA are irregular to spherical in shape, with sizes ranging from less than 1 µm to larger than 300 µm. In Australia, the majority of CCPs produced is categorised as Class F — being mainly SiO2 and Al02 (<70% ) and >10% CaO. Class F ash is highly pozzolanic and reacts with various cementitious materials.
Current and potential uses of FA include:
