Development and Application of Kinetic Hydrate Inhibitors in the North Sea

Abstract

Low dose kinetic hydrate inhibitors, developed as an alternative to thermodynamic inhibition of gas hydrates, are a branch of specialty treatment chemicals that is still considered "novel". Such inhibitors have only been a commercially viable alternative to hydrate prevention treatment in the last three years. During and subsequent to this kinetic inhibitors have been deployed and developed successfully for both mature assets and new developments in the North Sea. The kinetic inhibitors developed are termed Kinetic Hydrate Inhibitors, or KHI. Currently a KHI is being successfully deployed in the Hyde West Sole system in the Southern North Sea, and in May of 1998 the Eastern Trough Area Project (ETAP) will start up operations and will use KHI from day one of production. Much has been learned from the development and introduction of KHI products with careful consideration being given to any potential effect that will compromise, not only the production operations, but also the efficacy of any additional additives. Experience has shown that each system must be treated as an individual and the inhibitor tailor made to suit. Here water chemistry, gas composition, temperature, and application all play a major role in the decision process. The use and application of this information, enabling the selection of the most appropriate material can be termed as a complete systems approach. This paper highlights the rationale behind this approach and elaborates on the aspects associated with the deployment of KHI, that experience has shown to be major limiting factors. P. 397

Synthesis and application of a novel combined kinetic hydrate inhibitor

“…as hydrate inhibitors provide a guideline for the development of new green KHIs recently. There are varieties of KHIs utilized in the Gulf of Mexico, the Middle East for nearly a decade [17][18][19][20]. However, due to high cost for importing KHIs, there is few application in China, and the current technique to inhibit hydrate formation is still to inject alcohols such as methanol and ethylene glycol into pipelines.…”

Is subcooling the right driving force for testing low-dosage hydrate inhibitors?

“…At the present time, gas hydrates are generally prevented by injecting the so-called thermodynamic inhibitors, such as methanol, glycol, etc. However, these inhibitors may not be economical at high water cuts, and may pose many environmental and logistical issues (Phillips and Grainger, 1998). The Petroleum industry has responded to the economic and HS&E concerns by identifying and testing alternative low-dosage hydrate inhibitors (LDHIs).…”

Kinetic Hydrate Inhibitors - Sensitivity towards Pressure and Corrosion Inhibitors

“…KHIs have been successfully applied [11][12][13][14][15][16][17] , especially in the UK sector of the North Sea. Injection of LDHIs in place of thermodynamic inhibitors has been considered as the most interesting option regarding new methods to prevent hydrate blockages.…”