Case studies

Abstract

The aim of this chapter is to apply the results developed in the previous chapters to different real plants. The first application is about control of pH degree in a stirred tank, where a solution of high concentration of the acid ClH is mixed with water to obtain a liquid of controlled pH. The second application concerns the control of a nonlinear biological nitrogen removal process. Thus, design steps of an observer-based control scheme applied to the linearized model of a phenomenological model of the process are illustrated. The estimation algorithm is combined with the control technique to monitor the process. The goal of the control is the removal or at least the reduction of organic waste. The control law is based on the positive invariance concept that had shown efficiency in handling control constraints. The efficiency of both the control and the estimation is demonstrated via computer simulations.