Simulation and optimisation of Sahel gas sweetening unit in Libya
DOI:
https://doi.org/10.14311/AP.2026.66.0344Keywords:
natural gas, sweetening process, acid gas removal, piperazineAbstract
The gas sweetening process is one of the most important operations in the natural gas treatment system. This work explores the potential for enhancing the performance of the Sahel gas sweetening unit by adding 0.2 wt.% piperazine (PZ) to the conventionally used MDEA. The Aspen HYSYS software was used to simulate and optimise the process. The objective of the optimisation was to maximise the throughput. The optimisation variables were the lean amine temperature, the flow rate of the lean amine relative to the raw gas, and the multiple amine feed stage locations. The results show that the lean amine temperature has a more pronounced impact on the extraction of H2S than CO2. Compared to the reference case (only MDEA), the absorption of CO2 with added PZ has improved by 66 %; however, the H2S concentration increased from 2.901 ppm to 4.23 ppm. These findings show that MDEA is more effective than MDEA+PZ at increasing the throughput and capturing carbon, however, adding PZ to MDEA allows more CO2 to be absorbed than H2S.
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Copyright (c) 2026 Asma Etoumi, Mohamed Alhansh, Marwan Almabrouk
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