Wärtsilä targets high injection pressure for methanol

Wärtsilä 32M has proven itself as a diesel engine for years and is now in deliveries for greener operation with methanol enabled by a robust gas diesel (GD) fuel system, says Wärtsilä.

When the demand in the marine market started to increase for a fast-to-market, reliable and efficient solution, Wärtsilä decided to lean on nearly 30 years of industry-leading experience with the GD technology. The base for the first newbuild implementation was the Wärtsilä 32 platform with an updated version of the GD system adapted for methanol use.

The main advancement to older designs includes an uprated injector to allow for a significant increase in injection pressure up to 600 bar as well as a re-designed accumulator and flow fuse system to ensure reliable and safe operation at high pressures. Special stand-alone pump units were designed to make the installation of the methanol equipment flexible and not be limited by the space available in the engine room.

Key benefits of this higher injection pressure are that it ensures the highest level of fuel efficiency and supports in achieving a good emissions profile for methanol combustion.

In June 2023, Wärtsilä was contracted by Swedish ferry operator Stena Line to convert some of its vessels to operate with methanol fuel. The conversions will include the fuel supply system and engine modifications, as well as integrating the new installations with the ships’ existing systems.

The full scope of Wärtsilä’s supply package will include fuel tank instrumentation and valves, transfer pumps, low pressure pump skid, fuel valve trains, Methanol Fuel Pump Units and the automation of the system, engine conversions, and automation upgrade for the engine control room. The conversions are scheduled to take place in 2025.

On the newbuilding front, Wärtsilä will supply its hybrid propulsion system for four new heavy lift vessels being built at the Wuhu Shipyard for SAL Heavy Lift. Wärtsilä’s hybrid system will feature a variable-speed Wärtsilä 32 main engine capable of operating with methanol fuel. The hybrid system also includes energy storage, a PTO/PTI generator and motor, a multidrive converter, and the Wärtsilä Energy Management System for controlling and optimising the hybrid operations. The ships are scheduled for delivery in 2025.