\chapter*{Preface}
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This master's thesis was written as the final part of the study program Chemical Engineering at the Norwegian University of Science and Technology (NTNU). The thesis was written for the Process System Engineering group at the Department of Chemical Engineering in cooperation with Norske Skog Skogn.


I would like to thank my supervisor Prof. Sigurd Skogestad, and my co-supervisors Andreas Burheim Volden and Cristina Zotica. They have all three been extremely helpful throughout the work with this thesis and vital for the completion of it. I would also like to thank Norske Skog Skogn for letting me write my thesis in collaboration with them.  
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\section*{Declaration of Compliance}

\textit{I declare that this is an independent work according to the exam regulations of the Norwegian University of Science and Technology (NTNU).}


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Trondheim, 08.12.2018\\[3pc]
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Eirik Torp
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