Study of parameters influencing the properties of sintered fly ash aggregates

Pelletization is a promising process for making artificial aggregates from fine-grained materials like fly ash, which facilitates its high volume utilization as lightweight aggregate in concrete. A review indicates that only limited studies are reported on pelletization of fly ash aggregates. A study on the process of pelletization for the influences of angle of pelletizer disc, moisture content, affect of fineness of fly ash, and sintering temperature and its duration was undertaken. The salient observations are; i) for a chosen diameter of the pelletizer disc and the speed of revolution, the optimal angle of pelletizer has to be determined to maximise the pelletization efficiency, ii) adjustment of moisture content results in production of pellets of different size, and iii) for a given temperature and duration of sintering, pellets made with finer fly ash yield relatively higher strength.