چكيده لاتين
In recent years, due to the increase in energy carrier prices and the necessity to reduce environmental pollutants, attention to energy efficiency in process industries, especially in the petrochemical industry, has become increasingly important. The Sulfur Recovery Unit (SRU) is one of the high energy-consuming units in petrochemical and refinery complexes, aimed at converting sulfur compounds present in gas streams into elemental sulfur. In this study, the complete process of the sulfur recovery unit at Ilam Petrochemical Complex was simulated using Aspen Plus software, and the simulation results were compared and validated against operational data. After ensuring the accuracy of the simulation model, an exergy analysis was conducted to determine the exergy destruction and exergy efficiency of all process equipment. The results showed that the highest exergy destruction occurred in the distillation columns, which consume the most energy for heating and cooling services, indicating a high potential for thermodynamic performance improvement in the system.
Next, to identify the effective parameters on exergy destruction and unit exergy efficiency and to reduce energy consumption, a sensitivity analysis was performed on operational parameters such as temperature, pressure, and flow rates. Then, two objective functions, including minimization of energy consumption and minimization of exergy destruction, were defined. Optimization was carried out using the COOT metaheuristic algorithm with constraints reported by Ilam Petrochemical Company. To ensure the performance of the COOT algorithm, optimization was also performed using the Differential Evolution (DE) algorithm. Comparison of the algorithmsʹ performance showed that the greatest reduction in energy consumption was achieved by the COOT algorithm with the energy consumption objective function, resulting in annual savings of 18 billion Iranian Rials in auxiliary service consumption. Following that, the DE algorithm with the energy consumption objective function achieved annual savings of 17.8 billion Rials in auxiliary services. Regarding optimization with the exergy destruction objective function, the COOT and DE algorithms yielded annual savings of 14 and 15 billion Rials, respectively.
