LHV gas heater

A gas heater in a marine LNG fuel system raises the temperature of vaporized natural gas to the value the dual-fuel engine needs before the gas enters the fuel line, working with the vaporizer in the Fuel Gas Supply System (FGSS). On low-pressure systems it is usually a shell-and-tube heater; high-pressure ME-GI type systems use coil-wound exchangers downstream of the pump and vaporizer unit. The heater conditions gas temperature, and with the vaporizer adjusts the methane number, so the engine sees fuel within spec. The label LHV (lower heating value) is not a standard name for this component; the engine maker’s term is gas heater or gas conditioning heater.