Gas Solutions

Wärtsilä Gas Solutions offers innovative and energy efficient systems and solutions related to a number of oil & gas segments. The scope includes marine LNG and LPG cargo systems, fuel gas systems for marine vessels, onshore gas terminals, biogas systems, flare gas ignition, oil separation and tank control systems. The business unit has end-to-end responsibility from sales to commissioning of complete systems.

LNG Reliquefaction Systems

Wärtsilä has been a pioneer in this field since the early 2000s, and is today a leading designer, developer and supplier of energy efficient LNG BOG reliquefaction plants. We supply complete and integrated systems including BOG reliquefaction and fuel gas supply systems as compressor solutions, and LNG pump solutions required for feeding engines with low and/or high-pressure gas.

Our BOG reliquefaction process is based on reversed nitrogen Brayton cycle refrigeration technology, using commercial grade nitrogen to extract heat from the boil-off gas. During this reliquefaction, the cargo is kept cool and at the right pressure under all operating conditions. The systems allows a portion of the BOG to be used as fuel for the ship’s engines, while the excessive liquefied gas is returned to the main tanks to be sold as cargo. The systems can be designed to handle all boil-off gas, or only the excessive gas not used by the engines (partly liquefaction).

Wärtsilä’s Compact Reliq module is our updated offering, translated into a compact and reliable module. The Compact Reliq is also instrumented for remote monitoring and online operational support as part of Wärtsilä’s OPERIM programme.

BOG Reliquefaction site

LNG Regasification Systems

To use liquified natural gas (LNG) for purposes like fuel, power generation, heating and cooking, the LNG must be converted back to its gaseous state. This process is known as regasification, and typically takes place where LNG carriers discharge their cargo.

Wärtsilä Gas Solutions offers a range of regasification technologies for floating storage regasification units (FSRUs), barges, jetties, and onshore terminals. Our portfolio represents an industry benchmark in terms of energy efficiency, robustness, and operational flexibility.

Our track record includes delivery and commissioning of numerous floating LNG regasification plants based on either closed loop regasification technology, using steam with water/glycol as the intermediate heating medium, or open loop regasification technology using sea water with propane as the intermediate heating medium. In FSRU projects, Wärtsilä also offers engineering for the complete conversion – including integration of regasification modules like BOG compressors and power module, along with all the other systems for cargo handling, upgrading and utilities.

Our modularised regasification plants for jetty installations facilitate a much shorter construction time compared to conventional land-based terminals

Wärtsilä LNG Regasification Systems Site

VOC Recovery

Reducing VOC emissions primarily benefits our environment and climate
Volatile organic compounds (VOC) are light components of crude oil, which evaporate during loading operations or during the carriage of high-volatility crude oil cargoes. Traditionally this cargo vapour has been vented into the atmosphere to prevent the cargo tank pressure to exceed the design pressure. Such venting represents both an environmental problem and a great loss of energy. In total, the emissions of VOC from global sea transportation account for a total of more than 5 million tonnes per year.

The Wärtsilä VOC recovery system not only prevents these harmful compounds from being emitted to the atmosphere, it also condensates the VOC into two fuel fractions. One is used to power the recovery system itself– making it self-supplied with energy. Today, several shuttle tankers in the North Sea are utilizing this technology to increase the sustainability of their operations.

Wärtsilä VOC Recovery systems Site

Cargo Handling for small LNG Carriers

There is a growing demand for small-scale transportation of LNG to end users that are located in areas where pipelines are not feasible or economically viable. Typically, such end users are power generation plants, land based industries, and suppliers of LNG as fuel for vehicles or ships. Wärtsilä has developed a Cargo Handling System, the design of which is based on the extensive experience that Wärtsilä Gas Solutions has accumulated in delivering such systems for LPG, LEG and LNG carriers. The available scope includes:

  • Cargo handling system
  • Boil-off gas handling
  • Cargo tank design and complete tank delivery
  • Ship design
  • LNG fuel supply system

We provide designs for small size LNG Carriers carrying LNG only, or Multi Gas Carriers able to carry all types of gas cargo. Typically these ships are between 4 000 and 40 000 m3.

Cargo Handling for Small Scale LNG

Useful Downloads

Compact Reliq


VOC Recovery Systems