Cement kilns-a real control problem

For many years the cement industry has been searching for a means to improve combustion control in cement kilns so that temperatures and product quality can be optimised. Because of the variable composition of the raw materials used, the long residence times in kilns and instrumentation difficulties, kilns are fundamentally difficult to control. However, work during the last decade using knowledge and rule based techniques has shown that these problems can be overcome, there now being several proprietary systems available which can significantly improve kiln control and optimisation.