Three-Phase Wet Sour Gas Transmission in a Pipeline

Abstract

The basis of a wet process scheme involves minimum offshore processing. The reservoir
fluid is collected on a wellhead platform and routed without treatment via a three-phase
subsea pipeline to the shore where it is processed to deliver gas and condensates at
specifications. The concept and design will be applied to produce wet sour gas
transmission from offshore to shore via a subsea pipeline, resulting in a lower capital
investment. As a consequence two highly undesirable situations can exist at the same
time, severe corrosion and hydrate blockage, leading to system failure and the complete
shutdown of production. Therefore, both corrosion and hydrate inhibitors can be required
to effectively treat these phenomena. A solution of monoethylene glycol (MEG) is used for
hydrate prevention and an amine (methyldiethanolamine [MDEA]) will be added as a
buffering agent to maintain pH at a neutralizing value to managed corrosion. This
requires proper quality assurance of topside and subsea pipelines but will result in lower
capital costs as well as lower operational costs. In the proposed “Three-Phase Wet Sour
Gas Transmission in a Pipeline”, excellent engineering team will focus on the application
of a pH control system for carbonate reservoirs in order to prevent scaling.