DISTRIBUTED CONTROL SYSTEMS IN CEMENT PROCESSING PLANTS.

The development of automated process control in the cement industry has followed an evolutionary path similar to that taken by many other industrial process plants. In the early days process control meant a man walking round the plant adjusting hand wheels. Today it is a computer-based technology using distributed microprocessor control systems. This development has been achieved in four basic stages over a period of about 80 years. These stages are described in this article. Particular attention is obviously given to present day systems but a brief look at long-term future developments is also offered.