Malfunctions on pressure screens are usually detected in pulp mills by
measuring the differential pressure between the feed line and the acc
ept line of the screen as a warning signal. This method has several dr
awbacks. Tests performed in a pilot plant have shown the potential for
using a mathematical model of the pressure screen as a fault detectio
n tool. The objective of this approach is to monitor the process param
eters of the screen included in the model to detect incipient malfunct
ions and to prevent screen failure. The pressure screen model, based o
n mechanistic principles, is part of a general strategy for diagnosing
and controlling pressure screens which is being developed at the Pulp
and Paper Centre in The University of British Columbia, in collaborat
ion with Paprican.