Sensitivity analysis and process optimization of a natural gas dehydration unit using triethylene glycol

Dehydration of natural gas by absorption using triethylene glycol (TEG) is a common industrial offshore procedure to ensure the compliance with the required water dew point specifications for midstream transportation. Two thermodynamic models, the UMR-PRU and the TST/NRTL, are applied for the process simulation while a preliminary economic evaluation has been conducted revealing that both yield overall similar results as for the fixed capital cost which is found to be in good agreement with reported literature values. Moreover, sensitivity analysis of several operational parameters of the process has been performed and optimized values are suggested aiming to reduce its energy requirements. It is concluded that the optimized conditions do not actually affect the capital cost, but result in considerable reduction of the operating cost.