Kamyr digester monitoring and control

This paper addresses the implementation of a control loop performance monitoring system (CLPM) in a pulp and paper mill. The system chosen for the study is a continuous Kraft pulp digester which includes both fast and slow process dynamics, interactions and consequent disturbances. The aim is to track the performance of the control strategies implemented for this system, and to detect any significant deviation from control objectives and to give an indication about performance degradation. Different control strategies are used for the control of the digester: PID schemes, advanced model based control, and adaptive control schemes. When the actual control is not satisfactory, improvements are investigated.