Timetable:

Begin: 2000-01-01

End: 2003-03-31

Description:

Flotation is a difficult process to run efficiently. One way to make flotation performance better is to improve cell level control. However, controlling pulp levels in flotation cells is a complex control task because of strong interactions between the levels in the flotation cells. Therefore advanced controllers are needed to give good level control. This research dealt with a model of six flotation cells in series. Simulations were performed to compare different control strategies. Four control strategies were considered: one SISO controller and three different MIMO controllers. It was shown that level control performances of the MIMO controllers are significantly better that of the classical SISOcontroller.
The difference between different MIMO systems were somewhat smaller. All the controllers performed robustly to disturbances in pulp feed and to set point changes. The decoupling controller had the best IAE and IDE indices. However, the decoupling controller is sensitive to model uncertainties. This also means that process changes can strongly degrade the control performance.

Researchers:

Petteri Kämpjärvi

             This info last modified 2005-08-15 by Jerri Kämpe-Hellenius