الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The demand for high value petroleum products such as middle distillate, gasoline and lube oil is increasing, while the demand for low value products such as fuel oil and residua based products is decreasing. Therefore, maximizing of liquid products yield from various processes and valorization residues is of immediate attention to refiners. At the same time, environmental concerns have increased, resulting in more rigorous specifications for petroleum products, including fuel oils. These trends have emphasized the importance of processes that convert the heavier oil fractions into lighter and more valuable clean products. A number of technologies have been developed over the years for residual oil upgrading.
Catalytic hydrotreating (HDT) is a mature process technology practiced in the petroleum refining industries to treat oil fractions to remove impurities (such as sulfur, nitrogen, metals). Hydrotreating of the whole heavy crude oil before it goes to a crude oil distillation unit (CDU) is a new technology and is regarded as one of the more difficult tasks that have not been reported widely in the public domain. Recently published papers have demonstrated the significant improvement in middle distillate yields and quality of crude oil in terms of contaminants present when it is pre-hydrotreated.
Crude petroleum is a natural material containing thousands of chemical compounds. The refinery converts the crude into a wide range of products from transportation fuels and petrochemical feedstocks to asphalt and coke. All of these products must meet demanding specifications while the refinery stays within tight environmental constraints.
Small improvements in the design and operation of a refinery can deliver large economic value.
Computer models are used routinely today to model petroleum refining processes. Engineers use them to design new refineries, to improve the operation of existing refineries, to make decisions on purchasing crude, and to optimize the planning of production. The ability to accurately model each step in the refining process is the key to optimizing the performance of the integrated refinery.
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Modeling a refinery is challenging because crude petroleum consists of thousands of chemical compounds. The refinery takes the large molecules in crude oil and cracks them into the smaller molecules of transportation fuels. It must also carry out chemical reactions to tailor the composition of products to meet specifications.
These reactions take place through a complex set of reaction pathways.
The simulation process has the ability to input and modify the configuration of the process flow sheet and to perform design evaluations by considering the complete process flow sheet, before they are tried on the real plant. In this way it is possible to model and predict the behavior of the process flow sheet and to study different operation scenarios (Such as various feedstocks, high flow rates, modified operating conditions, etc.)
The main object of this contribution is to investigate simulation model for whole crude oil hydrotreating unit before any thermal treatment followed by atmospheric distillation unit to the resulted hydrotreated crude oil (non-conventional arrangement for refinery processes) in the sake of improving crude properties and consequently increasing the efficiency of the refining processes.
MIDOR (Middle East Oil Refinery) is an Egyptian refinery company used hydrotreating process to naphtha, and diesel petroleum products after distillation of crude oil (conventional arrangement for refinery processes), so it was chosen to be the main case study of this work in order to compare the results between MIDOR units conventional arrangement, and the suggested non-conventional units arrangement of this study; to show the change in crude productivity and products purity.
The validation of the suggested model was done through the experimental Iraqi crude oil hydrotreating unit pilot plant to Aysar Talib Jarullah; to ensure the validity of the results when applied to case studies; which are two case studies; the first one is MIDOR feedstock (50/50%mix of light and heavy Arabian crudes), and the other case study is the heaviest crude in MIDOR feed stock (Arabian heavy crude oil).
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The simulation model results showed a significant improvement in the characteristics of crude oil after hydrotreating process. Distillation products of resulted hydrotreated crude oil have enhanced properties with increasing in crude productivity of middle distillate fractions. Aspen Hysys V.9 was used as a chemical process simulator.