In this paper the effect on energy consumption and pollution of fuzzy autom
atic control of a rotary kiln is investigated. The computer-based fuzzy con
trol system is installed at the Larko ferronickel plant in Larymna, Greece,
by the Danish firm F.L. Smidth & Co. A/S. Operation characteristics for th
e manual operation against automatic control are defined and compared. Prel
iminary results show substantial energy savings and reduced pollution level
s. Payback period for the investment was calculated at approximately 1.2 ye
ars.