الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Nowadays, gas processing for Condensate, NGLs (Natural Gas Liquids) and LPG (Liquefied Petroleum Gas) recovery has gained a great interest due to the increase of the market demands as well as the higher prices of these products. However, many of the current Condensate, NGL and LPG recovery units in operation don’t give the expected revenue. This research is based on two major issues: 1. Optimization of the Existing Plant Operating Conditions Based on production data and operating conditions of the ABU-SANNAN Condensate Stabilization Unit (General Petroleum Company-Egypt) and by close monitoring of butanes content in stabilizer feed stream, overhead gases and bottom product (stabilized condensate), it is noticed that the process of the existing Condensate Stabilization Unit favors enrichment of butanes in the bottom product at the expense of pentanes plus (C5+) (Poor Fractionation). So, the need to achieve the highest efficient performance, maximum productivity rate, stable operation and reducing the operating cost of the existing Condensate Stabilization Unit by Optimization of the process operating conditions has led to this work. The Existing Condensate Stabilization Unit is simulated by using the Aspen HYSYS simulator V8.8 which is based on PENG-ROBINSON equation of state for calculations. Model results are verified by testing against the actual process operating conditions. Statistical analyses of the real operating plant data and simulation results are conducted to check for any deviation between them. The most important process variables and constraints that directly affect the production and performance ratio of the stabilization unit are discussed firstly to illustrate the relationship between the process operating conditions and the change could be appearing on the objective functions. Subsequently the optimal operating conditions are developed to achieve a stable column operation. The most effective operating variables investigated in this work are: outlet temperature of process gas from the mechanical refrigeration unit, stabilizer feed drum pressure, stabilizer column pressure, stabilizer feed temperature, stabilizer bottom temperature, stabilizer feed tray location, and stabilizer reflux ratio. IV The results show that, after development of the optimum process operating conditions, stabilizer bottom product purity increased by 0.80% and condensate productivity increased by 6.25% (33 BBLs/D), while total consumed power reduced by 4.16% (2.56 MMBTU/D). The economical analysis shows that there is excess revenue in the gross profit by about $ 1,594,050 per year as a result of optimization. The efforts done in this work are helpful and can be applied for plants in operation as well as the plants under design for increasing their profits. 2. Retrofitting the Existing Plant The current research work proposes a possible modification of ABU-SANNAN Condensate Recovery Plant to produce Liquefied Petroleum Gas (LPG) from Natural Gas Liquids (NGLs), instead of producing lighter hydrocarbon gases during the stabilization process, in addition to the current condensate and sales gas products. New process equipments selection, sizing and rating are performed by using Aspen HYSYS simulation program V8.8. The results show that the retrofitted plant can produce 87 Tons/Day of LPG. The produced LPG can participate to solve the LPG shortage problem in Egypt. The economic evaluation for the Retrofitted Plant is conducted by using Aspen Capital Cost Estimator V 8.8, to ensure rapid return of investment and good profitability over the expected lifetime. It was remarkable that the Retrofitted plant has a great value from the economic point of view as the total capital investment will be paid back within Two Years, so the Retrofitted plant will achieve high and rapid return on investment (ROI).