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Abstract In the petroleum industry, several trends are leading to the increase of hydrogen demand in oil refineries. The petroleum refinery industry aims to generate profit by converting heavy fraction of oils into valuable products. Hydrotreating and hydrocrackng are the major consumers of hydrogen in which a series of reactions convert heavier fractions to valuable products. At the same time, large amounts of hydrogen are produced as a by-product from catalytic reformer. Also, hydrogen can be recovered from off-gas of many processes such as delayed coking and catalytic cracking. The present study is divided into five main parts. The first part of this thesis addressed the problem of actual hydrogen distribution at Medor refinery plant at Alexandria-Egypt in which cascade analysis and mathematical optimization techniques were applied to minimize the consumption of hydrogen and the hydrogen discharge. The second part represents a proposed superstructure - based linear optimization model for the synthesis of hydrogen network with partitioning regenerators. Many methodologies based on process integration have been developed for hydrogen network in the past two decades. Some of these developed works consider the use of regeneration unit to further reduce fresh hydrogen intake after direct reuse/recycle potential is exhausted. However, there are limitations in these works that need to be overcome and has been addressed in this thesis. In this thesis, the optimization model proposed that there is one regenerator for each source (cascade regenerators), and there is no mixing of the regenerated sources. An industrial case study and three case studies from the literature are solved to illustrate the ease and applicability of the proposed method. In the third part, the inter- plant hydrogen integration model with selection the optimum purifier is represented. The inter- plant hydrogen integration is considered as a new technique that can be applied on hydrogen integration. This technique can be used in reducing the hydrogen consumption and the hydrogen discharge for different hydrogen networks in eco industrial plants. The two different schemes, direct and indirect inter- plant hydrogen integration are discussed. Five case studies were solved to illustrate the methodology of the models. In the fourth part, a multi-period approach for design of inter- plant hydrogen integration is represented to address the effect of changing in the operating conditions of refinery processes on the IPHI network. Two case studies are solved for the two schemes direct and indirect IPHI with multiperiod consideration. The multi-period inter- plant network design can operate under multiple periods of operation with lower total annualized cost compared to the hydrogen network designed without multi-period IPHI. In the final part, as an extension of the work done for inter- plant hydrogen integration in part three, different models for the selection of the optimum regenerators for inter- plant water integration are represented. One case study is solved by these different models to illustrate the difference between them. |