Exergy assessment of the separation train of a real production onshore oil and gas platform using Aspen Plus

Abstract

The petrochemical and chemical industries are among the most energy-intensive industries, accounting for more than a third of global industrial energy consumption. Rising raw material, infrastructure, and energy prices are squeezing profit margins in the chemical industry. The chemical industry is looking for more energy-efficient equipment and process design to reduce energy consumption. Exergy analysis can be a valuable approach for finding energy waste in such a situation. Exergy analysis can also be utilized to provide a high-level depiction of process change and environmental protection. This study investigated the separation trains of the ALRAR gas separation facility in Algeria, as well as prospective options for reducing exergy losses, and specifically answered the following research questions, which sections of the separation train suffer from high energy loss, and what are the potential solutions for boosting the exergy efficiency of the separation train, using a combination of both Aspen Plus and Aspen HYSYS simulations. This study aims to simulate the ALRAR separation train using Aspen Plus and Aspen HYSYS, conduct exergy analysis, pinpoint potential suggestions to improve the ALRAR separation train’s energy efficiency, and state meaningful thermodynamic performance parameters for plant evaluation. The results show that the air coolers (E-101) and (E-105) in the ALRAR gas plant have significant exergy losses, while the heat exchangers (E-104) and (E-103) have low exergy efficiency. Moreover, the exergy analysis resulted in the formulation of actionable recommendations to improve the train's exergy efficiency. Additionally, this work made a notable contribution by demonstrating how to integrate exergy analysis with Aspen Plus and Aspen HYSYS, as well as how to compute physical exergy with Aspen HYSYS.