OPTIMIZATION OF DRYERS FOR PAPER INDUSTRY

Abstract

The purpose of this paper is to present a state variable model. for the drying section of a paper-making machine. 1.This model is based on the mass and energy balance relationships written for steam, paper, cylindrical heater wall, and moisture. These relationships give a set of six nonlinear partial derivative equations. The form of these equations changes somewhat from one cylindrical heater to another. The solution for this model yields the operating parameters needed to achieve the desired steam temperature while obtaining good paper drying. Boundary conditions are specified by a stochastic generator, and initial conditions are obtained by solving the static model. The dynamic model is presented in [1]. In this paper, we present only the state variable model for the paper drying, as well as comparing the obtained results with dynamic model results. Solving the set of differential equations with respect to the boundary conditions, we obtain the standard form of the state representation, which represents the dynamic version of the model used for process control. In conclusion, it can be said that the consistency of the model with experimental results seems to be reasonably good and can be used for process control. New multiport dryer technology for the forest industry could greatly improve , the efficiency of dryers used in paper mills. The photo shows a fully assembled Multiport dryer insert installed in Kadant Johnson half-dryer. As machine operating speed increases, unbalance forces increase dramatically, leading to equipment reliability and product quality problems. Correcting dryer unbalance presents significant technical challenges, due to slow rotational speeds and phase influence of nearby dryers. A revolutionary new technique has been developed, using regular maintenance shutdowns as the opportunity for incremental corrections. This approach has proven especially valuable during speed-up projects. This paper describes the challenges, solutions, and benefits of the In-Situ [1 Roll Balancing technique.