A Review of Kinetic Hydrate Inhibitors from an Environmental Perspective

Abstract

Kinetic hydrate inhibitors (KHIs) have been used in the upstream petroleum industry for about 25 years to prevent plugging of flow lines with gas hydrates. The main ingredients in current commercial KHI formulations are one or more water-soluble polymers which contain both hydrophobic and hydrophilic functionalities. Although the vast majority of KHIs are low in acute toxicity and bioaccumulation, very few commercial products show good biodegradability, and for that reason, there is always some concern of long-term chronic toxicity from partially degraded products if discharged into the environment. This report reviews all efforts to develop more biodegradable KHIs, and outlines the fact that some classes of so-called "green" chemicals are not necessarily readily biodegradable or low in toxicity. The review also covers methodologies to recover or destroy KHIs and reduce their discharge to the environment.

The effect of surfactants on hydrate particle agglomeration in liquid hydrocarbon continuous systems: a molecular dynamics simulation study

“…Surface adsorption can also occur in KHIs those inhibit the formation and growth kinetics behaviours of hydrate crystals. 23,64 Based on previous studies, some AAs exhibit the same kinetic effects in the petroleum industry. 17,25 Therefore, additional simulations and experiments were performed to investigate whether the adsorption of the model surfactants could affect gas hydrate growth, and the initial simulation conguration is shown in Fig.…”

Performance of Waterborne Polyurethanes in Inhibition of Gas Hydrate Formation and Corrosion: Influence of Hydrophobic Fragments

“…Besides, many ionic liquids are simultaneously toxic [17] and low biodegradable materials [18,19]. In addition, all ionic liquids studied to date are poor KHIs [20]. Amino acids, such as glycine, alanine, valine, leucine, isoleucine, tyrosine, serine, arginine, and lysine have also been studied as inhibitors of methane and carbon dioxide hydrate formation [12,20,21].…”

“…In addition, all ionic liquids studied to date are poor KHIs [20]. Amino acids, such as glycine, alanine, valine, leucine, isoleucine, tyrosine, serine, arginine, and lysine have also been studied as inhibitors of methane and carbon dioxide hydrate formation [12,20,21]. However, they are not sufficiently effective, stable in solutions, and also promote the growth of microorganisms, since they are a nutrient substrate for them [22,23].…”

Inhibition Effect of Kinetic Hydrate Inhibitors on the Growth of Methane Hydrate in Gas–Liquid Phase Separation State

“…The natural gas required in various cities and industrial sites is mainly transported through pipelines, and generally the pipelines are in high-pressure and low-temperature environments. Therefore, hydrates may form and block the pipelines and valves and other components, causing serious industrial problems [1,2]. The traditional solution is to add thermodynamic inhibitors (TIs) to the system.…”