Patent ID: 8656726

Claim:
An apparatus for supplying natural gas fuel, comprising: a compressor having a compressor inlet for receiving a primary stream of natural gas from an ullage space of at least one liquefied natural gas storage vessel, and a compressor outlet communicating with a natural gas supply pipe; a forced liquefied natural gas (LNG) partial vaporiser comprising a vaporiser inlet for receiving a secondary stream of natural gas from a liquid storage region of the liquefied natural gas storage vessel, and a vaporiser outlet in communication with the natural gas supply pipe downstream from the compressor, the forced liquefied natural gas partial vaporiser including: a vaporisation chamber having heat transfer means, an inlet to the vaporisation chamber for the liquefied natural gas, a mixing chamber downstream of and in communication with the vaporisation chamber, a first inlet to the mixing chamber in communication with an outlet from the vaporisation chamber, a second inlet to the mixing chamber in communication with a source of liquefied natural gas: means for disengaging unvaporised liquefied natural gas in communication and operatively associated with the mixing chamber; valve means for controlling relative flows of the liquefied natural gas to the vaporisation chamber and the mixing chamber; and a programmable logic controller operatively associated with the forced liquefied natural gas LNG partial vaporiser means, the programmable logic controller comprising an algorithm for determining a temperature at which the forced liquefied natural gas LNG partial vaporizer means is operated and for determining compositions of the unvaporised liquefied natural gas and the vaporized natural gas.