Performance evaluation of pulper consistency control with dead-time compensation
De Bruyne, Franky * De Pauw, Eric * van Laer, Maarten * Hanssens, Guy * Wauman, Walter * Schoonjans, Stijn * Vidts, Jeroen * Saey, Philippe * × Verhiest, Gilbert * #
Technical Association of the Pulp and Paper Industry
Tappi vol:84 issue:3 pages:1-10
In this paper, we study the implementation of a pulper consistency controller for the recycled
paper industry. Variations in the weight and the quality of the raw material, i.e. recovered board
and paper, are known to cause consistency variations which, in turn, cause variations in the basis
weight and the moisture level of the end product, i.e. recycled paper. The first step towards
rejecting these consistency variations is to implement a consistency controller in the pulper itself.
We propose a combination of feedforward and feedback with dead-time compensation as the
paper dissolving process is characterized by a dead time that is large in comparison with the time
constant of the process. We describe the implementation of the controller from the pulper
modeling phase to the discussion of the experimental results.