الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In a petrochemical plant, gases separation and fractionation process is a very important step in which the desired final product is recovered. In the propane dehydrogenation plant (PDH), developed by Uhde for the Egyptian propylene and polypropylene company (EPP), propane is partly converted into propylene and hydrogen through the main dehydrogenation reaction. Lighter hydrocarbons and CO2 are formed due to side reactions. Heavier components which are present in the fresh feed are also found. Reaction effluent is compressed for further processing which involves CO2 removal followed by light gases separation and fractionation to have final product of polymer-grade propylene which is further processed in the polypropylene plant (PP) into a final product of polypropylene. However, the claimed conversion and selectivity were not achieved. In another aspect, reaction effluent changed in both composition and conditions from that stated by design. Consequently, the gas separation and fractionation unit could not handle this situation efficiently. Propane/propylene recovery was 5.92% less than that expected by design due to the lower efficiency of the deethanization process. Therefore, a modification included changes in process configuration and some operating conditions, was proposed, in order to achieve accepted propane/propylene recovery. A comparative process simulation by HYSYS was done for three cases; design basis process, real operating process and the modified process. Simulation results showed that the modification can increase Propane/propylene recovery by 5.77%. Although the modified process was less CO2 tolerant than the original operating process, it was able to handle other operational problems like increased carryover in the deethanizer composite column. The modified procedure was applied in the existing plant and the lab analyses showed good agreement with the simulation results.