Many of the models used in the flowsheet simulation of solids processes are more or less empirical. In order the get reliable results from a flowsheet simulation it is often necessary to adjust model parameters to measured data. Because measured values are always erroneous to some degree in the first step a data reconciliation calculation has to be performed. Based on the reconciled data that fulfil the balance equations the adjustment of the model parameter can be done by use of numerical optimization methods. In the present work a method for data reconciliation as well as for the adjustment of model parameters has been developed with respect to solids processes. The developed methods have been implemented as extensions of the flowsheet simulation system SolidSim. The practical application of the developed extensions is illustrated by example of a process for the dressing of brown coal operated by RWE Power AG in Germany. (c) 2007 Elsevier B.V. All rights reserved.