Ammonia for shipping

Liquid ammonia can be stored at a pressure above 8.6 bar at ambient temperature (20°C). To keep it  liquid  when the ambient temperature increases, many ammonia tanks are designed for approximately 18 bar.

Ammonia can be used as an alternative fuel. Research explores the use in different sectors. The two-stroke ammonia engine by MAN Energy Solutions will offer the possibility to use this future fuel as a resource for shipping.

There are several challenges concerning ammonia.

• Ammonia is more difficult to ignite compared to other fuels. It burns slowly and has a high evaporation enthalpy. Furthermore, the emission characteristics will be different from conventional engines. 
• Another factor to recognize is the on-board handling and safety. Ammonia itself is toxic and possesses an unacceptable odor even in low concentrations. Although the handling is known from ammonia tankers, it is significantly more difficult than that of LPG or methanol. Also, no venting to the surroundings is permitted

• Ammonia is carbon- and sulphur-free and gives a clean combustion with near-zero generation of CO₂ or SO_X
• Its volumetric energy density is higher than that for hydrogen.
• As it is already widely used in the industrial process as an agricultural fertilizer, it is a commercially attractive product.