South-Pars Phases 2 and 3: The Kinetic Hydrate Inhibitor (KHI) Experience Applied at Field Start-up

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractSouth-Pars Phases 2&3 development in Iran is a "wet scheme" base design: no process is performed offshore, all the produced fluids (sour gas + condensate + water) are directly sent to shore through two 32" 109 km long sea lines. Corrosion and hydrate protection is based on buffered glycol (MEG+MDEA) which is regenerated onshore and sent back to the platforms through two 4½" piggyback lines.The concomitant injection of a Kinetic Hydrate Inhibitor (KHI) and a Corrosion Inhibitor (CI) was initially considered as a back-up solution. This paper presents the field experience with KHI and CI injection which had to be applied for the field start-up during respectively 125 days and 80 days for each sea line.This case represents the first large field application of KHI in the Middle-East and the potential of such Low Dose Hydrate Inhibitor (LDHI) is underlined.

Kinetic Hydrate Inhibition by Lambda-Carrageenan and Its Synergistic Compositions with Ethylene Glycol, 4-Methyl-1-Pentanol, Polyvinylpyrrolidone, and Polyvinylcaprolactam

“…In our previous studies, ,− we have conducted several similar experiments and have found a similar variation in the results with variations around ± 5–15%. A similar variation in results has been observed by several other researchers. − , Therefore, we can expect a similar 5–15% variation in all the results reported in this study.…”

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Rheological evaluation of kinetic hydrate inhibitors in NaCl/n‐heptane solutions

“…If the contents of hydrocarbon multiphase pipelines are at thermodynamically favourable conditions (low temperatures and high pressures), hydrate crystal formation may occur . The solid hydrate particles may aggregate with time and can then block the flow .…”

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