A Technical Review on Optimization of a Natural Gas Conversion Process for Liquefied Petroleum Gas (LPG) Production

Liquefied Petroleum Gas (LPG) production from Natural Gas Liquids (NGLs) is an energy-intensive process that relies heavily on efficient distillation operations, particularly within deethanizer, depropanizer, and debutanizer columns. This review examines recent advances in the optimization of natural gas conversion processes for LPG production, with emphasis on improving energy efficiency, reducing operational costs, and minimizing carbon dioxide (CO₂) emissions. Various optimization approaches reported in the literature are analyzed, including thermodynamic modeling, exergy analysis, Response Surface Methodology (RSM), Genetic Algorithms (GA), Artificial Neural Networks (ANN), and driving force methods. The reviewed studies commonly employed simulation tools such as MATLAB, AVEVA PRO/II, and ChemSep for modeling and optimization of distillation systems. The reviewed works demonstrate that optimization of operating variables such as reflux ratio, column pressure, and sequence configuration can significantly reduce energy consumption while maintaining product purity requirements, but little study have been made on the simultaneous optimization of debutanizer and depropanizer columns using integrated simulation platforms such as Aspen HYSYS while considering multiple interacting variables such as: Feed tray location, column Pressure and Reflux Ratio. 

Energy efficiency, Distillation column optimization, Aspen Hysys, Liquefied Petroleum Gas LPG

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