Optimization of the Pulp Mill Economical Efficiency; study on the behavior effect of the economically significant variables

In the recent paper Castro and Doyle (2004) have proposed the Pulp Mill benchmark model, having the standard architecture with a Kamyr digester, a bleaching plant and a chemical recovery. Further Mercangöz and Doyle (2008) have performed the optimization of the benchmark model. The optimization is based on the approximation of the steady state values of the economically significant variables by linear functions of the decision variables (the decision variables are mainly setpoints of the control loops, the economically significant variables are mainly the most important manipulated variables of the plant).