Whey protein as a sustainable hydrate inhibitor for enhancing flow assurance in natural gas pipelines: implications for environmental sustainability

To maintain the efficient operation of the oil and gas industry, ensuring the continuous and unobstructed transport of hydrocarbons through pipelines is essential, particularly in preventing flow disruptions caused by hydrate formation. Kinetic hydrate inhibitors (KHIs) have emerged as a widely studied solution due to their ability to effectively delay hydrate formation at low concentrations, typically between 0.5 and 2% of the water phase. This approach enhances both operational safety and efficiency. However, a major drawback of conventional KHIs is their non-biodegradable nature, raising environmental concerns and regulatory restrictions. Consequently, there is a pressing need to identify, develop, and rigorously evaluate sustainable and biodegradable alternatives. This investigation explores the potential of whey protein as a natural hydrate inhibitor, assessing its effectiveness in mitigating hydrate formation while addressing environmental sustainability challenges. To evaluate its effectiveness as a hydrate inhibitor, the induction time (IT, denoted as t_i) for hydrate formation was recorded under varying conditions, specifically at concentrations of 0.25, 0.5 and 1 wt.%. Experiments were conducted using methane (CH₄) gas at a pressure of 7.6 MPa, where the equilibrium temperature (T_eq) for hydrate formation is 10.45 °C. The cooling rate was systematically controlled at 1 °C/h below this equilibrium threshold. Findings from the study indicated that while whey protein displayed slightly reduced inhibitory efficiency in comparison with commercially available KHIs, it presents a promising biodegradable alternative to conventional, non-sustainable KHIs. This is particularly significant for offshore applications where environmental concerns take precedence. The ability of whey protein to effectively inhibit hydrate formation, combined with its natural origin and biodegradable properties, positions it as an attractive candidate for future research in the field of deep-sea hydrate risk management.