Unmasking Heavy Hydrocarbon Blockages

Unmasking Heavy Hydrocarbon Blockages

From LNG Unlocked by AI by OSSA LNG

March 16, 2026 · 21 min

About this episode

This episode investigates the chemical processes causing heavy hydrocarbon blockages in LNG vessels and discusses operational solutions to prevent them.

Unmasking Heavy Hydrocarbon Blockages in LNG Vessels In this episode, we conduct a deep-dive investigation into a recurring nightmare for LNG cargo engineers: the total blockage of low-duty (LD) flow meters and cryogenic compressors. What often looks like a mechanical failure or a faulty sensor is actually an insidious chemical process occurring inside the ship's pipework. We explore the "invisible sludge" caused by heavy hydrocarbon fractions (C6+, pentane, butane) and carbon dioxide that freeze solid at temperatures where methane remains a gas. This episode breaks down the "sourdough starter" effect of failing to rotate heel tanks , which concentrates these heavy molecules into a thick, brown brine that chokes the system. Key topics covered in this episode: The CoQ Discrepancy: Why official Certificates of Quality can report "zero" heavy hydrocarbons while your filters are physically "choking on solid pentane ice". The Pre-cooling Trap: How a necessary operational step can accidentally trigger the Joule-Thompson effect , manufacturing ice directly onto protective 600-micron strainers. Tactical vs. Permanent Fixes: A guide to the nitrogen purging temporary fix and the…

People in this episode

Host: OSSA LNG

Topics covered

  • heavy hydrocarbon blockages
  • LNG cargo engineering
  • cryogenic processes
  • mechanical failures
  • operational procedures
  • chemical processes

Keywords

  • LNG
  • heavy hydrocarbons
  • cryogenic compressors
  • flow meters
  • nitrogen purging
  • hot gassing
  • sourdough starter effect
  • heel tanks

Mentioned in this episode

Organizations: LNG

Products: low-duty (LD) flow meters, cryogenic compressors, sourdough starter, nitrogen purging, hot gassing, 600-micron strainers, Certificates of Quality, heavy hydrocarbons, pentane, butane

More episodes of LNG Unlocked by AI

Explore listener stats, chart rankings, contacts and more on the LNG Unlocked by AI podcast page.