Using Casein Peptone as a Sustainable and Natural Solution for Mitigating Gas Hydrate-Induced Flow Assurance Challenges in Natural Gas Pipelines

Abstract

Abstract Casein peptone efficacy as a hydrate inhibitor is investigated, as is its potential for synergy with two eminent kinetic hydration inhibitors (KHIs), polyvinylcaprolactam (PVCap) and polyvinylpyrrolidone (PVP), to improve hydrate inhibition performance. The induction time (IT) / hydrate formation delay time and the average hydrate growth rate (AHGR) post-hydrate formation at concentrations of 0.25 wt%, 0.5 wt%, and 1 wt% of casein peptone were evaluated for methane gas at 7.6 MPa, with a hydrate equilibrium temperature of 10.45°C. 1°C/h constant cooling rate is used in the hydrate formation tests. The individual effectiveness of casein peptone, PVP, and PVCap is evaluated. The synergy between common KHIs (PVP and PVCap) and casein peptone is assessed by creating 1:1 blends of casein peptone with PVP and PVCap, with the individual performance of PVP and PVCap at an equivalent total inhibitor concentration (KHI + synergist and KHI) for a fair comparison. Casein peptone is found to have a promising hydrate inhibiting performance in the study. At similar concentrations, it outperformed the conventional KHI PVP40K, demonstrated similar efficacy to the conventional KHI PVP10K, and exhibited only slightly lower performance than the conventional high performing KHI PVCap 40K. This finding highlights the potential of casein peptone as a viable alternative to traditional KHIs, particularly for offshore locations where environmental concerns are a priority. The ability of casein peptone to inhibit hydrate formation at levels comparable to existing conventional inhibitors, coupled with its natural origin and biodegradable properties, make it an attractive candidate for future research in the field of deep-sea hydrate risk management.