Computer Control of Rotary Kilns

A dynamic lime kiln simulation model has been developed and validated by extensive test data from pulp mill lime kilns. The simulation is used to evaluate control and equipment requirements during transient or upset conditions. Control strategies and equipment, or kiln subsystem modifications can be perfected and implemented with a high degree of confidence in rapid installation and startup. This approach has been used to develop a computer-based rotary kiln control system which has been field-proven to meet design goals of: lower energy consumption, improved product quality, reduced equipment wear and tear, and automatic closed-loop control within days of initial installation. The rotary kiln control system is in operation at a Magnesia plant and at two West Coast pulp mills, where the systems have demonstrated an 8% - 10% fuel efficiency improvement in addition to other operational benefits.