Multifaceted Approaches for Controlling Top-of-the-Line Corrosion in Pipelines
This paper reviews the mechanisms of initiation and the prevention of top-of-the-line corrosion (TLC). Practical, multifaceted techniques based on the most recent research and developments will be described and then illustrated with documented sources to arrive at the best practices for control of this significant corrosion manifestation.
The rapid expansion of the production of oil and gas from unconventional sources requires the annual construction of thousands of miles of new pipelines, which will experience a bewildering and changing range of conditions that will require the use of new and innovative internal-pipeline-corrosion-protection methods that have been tested in field applications. These new corrosion-protection methods will be needed because of the complex corrosive environment of multiphase- and stratified-flow pipelines (including gathering lines), which is frequently observed in new shale-play production.
Conventional corrosion-inhibition methods (continuous or intermittent injection) may not be effective for inhibiting the pipelines because physical contact of the inhibitors is difficult to achieve in multiphase flowing systems at the top of the line (TOL). In addition, the pipelines must be piggable to be cleaned and treated properly, and traditional slug- or continuous-treatment methods have been found to be less than adequate where conditions exist for TLC to occur.
Several innovative methods are being developed to provide effective and long-lasting protection to the entire pipeline surface, including the use of pig trains with inhibitor slugs, improved inhibitor chemistries, inhibitors added to gels and foams, and special pigs that provide a 360° spray of inhibitor chemicals. The newer methods will be compared with the older technologies.
Improving Gas Dehydration With Preinhibited Glycol
The paper discusses dehydration performance of two units in two plants—with preinhibited glycol/antifoam/pH adjuster blend vs. neat glycol with periodic injection of antifoam and pH-adjuster inhibitors. The insights present an opportunity for significant operating and capital costs reduction.
Localized Pitting Corrosion of Superduplex Stainless Steel in a Seawater Application
During the dismantling and removal of fire-water-pump columns of superduplex stainless steel barely 1 year after plant startup in a redeveloped brownfield offshore Nigeria severe localized pitting corrosion was observed in the columns. This paper explores the findings and identifies the reasons.
Offshore Production in the Gulf of Thailand
Oil and gas producers in the Gulf of Thailand face unique technical challenges. This review of papers illustrates some of the innovative solutions used in the region.
07 November 2017
01 November 2017
14 November 2017