Marine vessels can be fuelled by LNG (Liquified Natural Gas). Clearly, as also with LNG, marine vessels need to be refuelled or bunkered at certain intervals. The bunkering operation usually takes place in port, but may also take place at other locations, e.g. at a floating bunkering facility out at sea.
The bunkering operation of an LNG fuelled marine vessel usually takes a long time. The reason for this is the temperature difference between LNG (normally about −162° C.) and the bunkering line (normally in ambient temperature, around +20° C.). This temperature difference causes the LNG to boil in the bunkering line, which leads to a two-phase flow of gas and liquid. The two-phase flow causes control problems and pressure pulses, which are harmful for the supply procedure and for the piping arrangements of the bunkering line. Consequently, in order to arrive at a functioning bunkering operation, the LNG flow rate has to be kept very low in the beginning of the operation in order to minimize, or at least in order to attempt to keep the pressure pulses at an acceptable level. After the bunkering line starts to cool down, the flow rate may slowly be increased. The bunkering operation consequently takes a very long time.
A typical practice and trend in marine vessel operation of today is shortened port times and high operating speeds, the latter with high energy consumption, which would necessitate a transfer of large amounts of fuel to the marine vessel in a short time. Such fast transfer of fuel is not available in the prior art.