Session: 12-06-01 Blue Economy VI: Offshore Decommissioning, Circular Economy, and Maritime Emissions Reduction

Submission Number: 181550

Reducing Boil-Off Gas (BOG) Emissions of LNG Fueled Ships (Phase 2: Application to Ships Under Construction) 

This study presents the development and field application of a shore-based boil-off gas (BOG) treatment system designed for LNG-fueled vessels during berthing. During the commissioning phase, when propulsion and auxiliary systems are inactive, onboard BOG consumption is significantly reduced. Consequently, ambient heat entering the LNG fuel tank induces vaporization and pressure buildup, often resulting in the release of BOG into the atmosphere. Given methane’s high global warming potential, such uncontrolled emissions pose a serious environmental concern.

To address this issue, a compact and modular BOG treatment unit was developed in a containerized configuration. Housed within a 40-foot container, the system comprises an oil-free BOG compressor, a heat exchanger, and an odorant injection module. It supports flexible deployment either onshore or onboard and operates using vessel-supplied utilities or external power sources. Remote operation is enabled via a secure private 5G network, ensuring safe and reliable control even under limited access or manpower conditions. Key design considerations included minimizing utility consumption, maintaining oil-free operation to prevent fuel contamination, and ensuring seamless integration with existing shipyard infrastructure.

Operational challenges, such as odorant injection instability and thermal limitations in the control panel, were addressed through engineering refinements. Verified through actual vessel commissioning, the system demonstrated stable performance and practical effectiveness in mitigating methane emissions. Beyond shipyard deployment, the system is extendable to port-side operations, particularly in regions where shore power is mandated and onboard BOG utilization is restricted—a condition commonly referred to as cold ironing. Under such constraints, LNG-fueled vessels often rely on temporary measures such as pressure holding, which involves absorbing ambient heat to increase tank pressure. With appropriate port infrastructure, the system enables efficient BOG treatment and reuse. Furthermore, integration with existing city gas pipelines allows the recovered BOG to be utilized as a clean energy source, contributing to more sustainable port operations.

Overall, the system provides a viable solution for methane emission reduction during LNG vessel commissioning and berthing, supporting the broader transition toward maritime decarbonization.

Presenting Author: Jaeseung Roh HD Korea Shipbuilding & Offshore Engineering Co., Ltd.

Presenting Author Biography: 4 years of experience in risk assessment and safety engineering for offshore plant projects.
Over 9 years of expertise in process design and engineering of Fuel Gas Supply Systems (FGSS) for LNG-fueled vessels, including alternative fuel integration.
Master of Science (M.S.) in Chemical Engineering

Authors:

Jaeseung Roh HD Korea Shipbuilding & Offshore Engineering Co., Ltd.
Duhee Lee HD Hyundai Heavy Industies Co., LTD.
Hyungwook Park Donghwa Pneutec
Sung-In Park HD Korea Shipbuilding & Offshore Engineering Co., Ltd.