| Processes with recycle are thoroughly studied in this document. Then, the control of such processes is analysed.; Because of the complex nature and the variety of industrial processes with recycle, a first-order model is used in a first step. In a second step, more complex models with physical non-linear equations are used.; For all these processes, two control strategies are compared. In the first one, the knowledge that the process is a process with recycle is ignored. In the second one, the controller is split into two parts: a controller for the direct (feedforward) path and a controller for the recycle (feedback) path.; Overall, the thesis demonstrates that the negative effects of the recycle on the process dynamics can be overcome when the effects of recycle can be anticipated even though the model of the recycle path is not precise. |
