Investigation of Hydrate Inhibition System for Shallow Water Gas Field: Experimental Evaluation of KHI and Simulation of MEG Regeneration Process

Abstract

In this study, a hydrate inhibition system is investigated for shallow water gas fields. Mono-ethylene glycol (MEG) injection has been used as a typical method for inhibiting hydrate formation in gas fields; therefore, most offshore platforms are equipped with MEG injection and regeneration processes. A recent application of a kinetic hydrate inhibitor (KHI) has reduced the total volume of MEG injection and hence reduce the operating cost. Experiments are designed and performed to evaluate and verify the KHI performance for inhibiting hydrate formation under shallow water conditions. However, the shut-in and restart operation may require the injection and regeneration of MEG. For this operation, the MEG concentration must be optimized while considering the cost of MEG regeneration. The obtained results suggest that decreasing MEG concentration from 80 wt% to 70 wt% can reduce the life cycle cost (LCC) of MEG regeneration process by approximately 5.98 million USD owing to reduced distillation column cost. These results suggest that the hydrate inhibition system must be evaluated through well-designed experiments and process simulations involving LCC analysis.