Clueless on LNG Cargo Operations-Loading

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LNG Unlocked by AI

Technology

Welcome back to our next episode, where we explore the hidden complexities of the world around us!

In this episode, we take you on a fascinating journey into the meticulous process of loading liquefied natural gas (LNG) onto massive tankers—a crucial operation that plays a vital role in the global energy supply chain.

Join us as we sit down with a seasoned ship captain who shares firsthand insights from the frontlines of LNG operations. Discover the intricate choreography between ship and shore, where safety protocols and precise procedures are paramount. From the extensive preparations that begin at sea to the final checks before departure, we uncover the detailed steps involved in this high-stakes operation.

Key Takeaways:

  • Learn about the critical ship-shore safety checklist that ensures seamless communication and safety before any loading begins.
  • Understand the importance of managing heel quantity and how it prepares tanks for subsequent loading.
  • Dive into the technology behind the custody transfer and measurement system (CTMS), which guarantees accurate tracking of LNG volumes transferred.
  • Hear about the innovative water curtain system that protects vessels during loading and mitigates risks associated with potential leaks.

With compelling anecdotes and comprehensive explanations, this episode provides a unique look into an industry often overlooked by the public. Whether you're a seasoned professional or just curious about how LNG is handled, this episode promises to be both enlightening and engaging.

Press play now to explore the intricate world of LNG loading!


Pre-Loading Preparations

  1. Ship Arrival and Mooring: The L arrives at the terminal,d is securely moored at the berth[6].
  2. Safety Checks: A safety inspection is conducted by terminal and ship representatives to ensure all safety equipment is in place[6].
  3. Connections:
  • The shore gangway is fitted for access between terminal and ship[6].
  • ESD (Emergency Shutdown) cables are connected[6].
  • Loading arms are connected to the ship's manifold[5].
  1. System Purging: Loading arms and manifold pipes are purged with nitrogen to reduce oxygen content below 2%[4][7].

Cool-Down Process

  1. Line Cool-Down: The terminal begins pumping LNG at a slow rate for about 15 minutes to cool down the loading lines[7].
  2. Gradual Cooling: This prevents thermal shock to the primary containment system and avoids vapor lock formation in pipelines[7].
  3. Temperature Target: The system is cooled to around -110°C to -130°C[4].

Loading Operation

  1. ESD Testing: A cold ESD test is performed to ensure valves close properly at low temperatures[6].
  2. Commencement: Loading begins at a slow rate, typically around 1,000 m³/hr[3].
  3. Ramp-Up: The loading rate is gradually increased to full rate, which can range from 8,000 to 13,000 m³/hr[3][4].
  4. Pressure Management:
  • Boil-off gas is managed using compressors to return vapor to shore[7].
  • Tank pressures are monitored closely[7].
  1. Balancing: Deballasting is performed to maintain ship stability as cargo is loaded[3].
  2. Distribution: Cargo is evenly distributed among tanks using a staggered filling approach[3].

Completion and Disconnection

  1. Rate Reduction: About one hour before completion, the loading rate is ramped down[6].
  2. Final Measurements: Custody transfer measurements are taken to confirm loaded quantity[3].
  3. Draining and Purging:
  • Loading arms and lines are drained of remaining LNG[5].
  • Systems are purged with nitrogen to create a non-combustible atmosphere[6].
  1. Disconnection: Loading arms are safely disconnected from the ship's manifold[5].

Throughout the operation, constant communication between ship and shore personnel is maintained, and all safety protocols are strictly followed[1][2]. The entire process is carefully monitored and controlled to ensure safe and efficient loading of the LNG cargo.

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