Analysis of the Operation of a Rotary Cement Kiln Using Unconventional Fuels.

Industrial wastes such as acid sludges, hardened rubber materials, bleaching earth, etc. , can be satisfactorily disposed of in a rotary cement kiln as long as the sulfur content in the waste material is below a specified value. The SO//3 content in the reacting powder, sampled in the transition zone at about 800 degree C, can be assumed to be the control parameter. An analysis of long-term operation of the kiln with these fuels made it possible to draw up an economic balance and to estimate the resulting energy saving.