---

With liquefied natural gas (LNG) becoming increasingly viable and popular as a marine fuel, Finland's Wärtsilä is continuing to develop technical solutions that are designed to facilitate this trend. The latest Wärtsilä developments in this field involve an upgraded version of the Wärtsilä LNGPac, a fully integrated fuel gas handling system, and improvements to the Wärtsilä Gas Valve Unit (GVU).

Wärtsilä introduced the LNGPac in 2010. It comprises a complete system for LNG fuel handling, which when introduced included the bunkering station, the LNG tank and tank connection space with the required process equipment, the heating media skid, and the control and monitoring system.

The system has proven to be a valuable enabler of LNG fuel for marine applications with more than 20 LNGPac systems in operation or under construction.

By upgrading the system into a more compact and technically advanced version, Wärtsilä says that safety and reliability will be enhanced, while the capital and operating expenditures will be reduced.

The new system has fewer moving parts, and therefore, in theory, less maintenance will be required. Furthermore, the compact design and advanced integration of components is said to make installation at the shipyard faster and easier.

The heating media skid, used to evaporate LNG for pressurising the storage tank and to provide the engine with the correct gas temperature, has now been removed as have the pumps. In looking beyond the fuel gas system, Wärtsilä has integrated multiple interfaces within the LNGPac. The new LNGPac directly utilizes the engine's cooling water, which results in fewer interfaces and less installation work for the shipyard. By eliminating electrical consumers, Wärtsilä enables the vessel to become even more environmentally friendly.

A similar improvement is made to Wärtsilä's cold recovery solution, which enables the cold energy of the LNG to be utilized by the ship's heating, ventilating, and air conditioning (HVAC) system. In the new cold recovery system, Wärtsilä directly connects the ship's HVAC (or other refrigeration systems) to the tank connection space, thus removing a complete circuit consisting of heat exchangers, valves and pumps.

The Wärtsilä GVU is a module located between the LNG storage system and the dual-fuel engine. It is used to regulate the gas pressure and ensure a safe disconnect of the gas system should that be necessary. By combining the LNGPac and the GVU into a single, fully integrated system, considerable space can be saved and a simple 'plug and play' solution will save installation time and costs for the yard, according to Wärtsilä.

New solutions have been applied to a number of aspects of the new, compact fuel gas system. These include an integrated airlock and control cabinet, a more compact bunkering station, an enclosed or integrated gas valve unit, and maximised LNG storage volume. Several of the features have been patented by Wärtsilä.

Wärtsilä is an industry leader in the development of duel-fuel engine technology, and has played a key role in developing a complete value chain of systems, solutions and bunkering arrangements - both onboard and shore-based - to accelerate the use of environmentally sustainable and economically competitive LNG fuel.

The upgraded LNGPac system is being officially launched this week at the Offshore Northern Seas 2014 (ONS 2014) conference and exhibition, in Stavanger, Norway from August 25 to 28. Wärtsilä experts will be on hand at stand number K115 to further explain the benefits of these latest innovations.

The new LNGPac will also be featured at the SMM 2014 exhibition being held in Hamburg from September 9 to 12, stand 305 in Hall A4.

Image: Wärtsilä's LNGPac fully integrated fuel gas handling system.