A LG module for a marine vessel (1), said LG module (10) comprising a support structure for loading and unloading said LG module (10) onto said marine vessel (1), at least one LG tank (12) and a LG gas processing unit (13) for processing LG to fuel, said fuel fulfilling the requirements of an engine of said marine vessel (1).

A methane transportation system is provided. The system may include a methane source configured to dispense methane at a first location, and an underwater vehicle. The underwater vehicle may include a propulsion system configured to transport the underwater vehicle underwater from the first location to a second location and a vessel defining a storage chamber configured to receive water and the methane from the methane source. The storage chamber of the vessel may have a pressure exceeding one atmosphere and a temperature during transport from the first location to the second location sufficient to form methane clathrate in the storage chamber. The system may further include a methane receiver configured to receive the methane released from the storage chamber at the second location. Related methods are also provided.

A plant for regasification of LNG includes a pump boosting LNG pressure, an LNG/coolant heat exchanger producing NG from LNG from the boosting pumps, and a closed coolant loop extending through the LNG/coolant heat exchanger and including a heat exchanger. The coolant from the heat exchanger is passed through the LNG heat exchanger as a gas and leaving in a condensed state to produce NG by thermal exchange. A heating medium is used within the heat exchanger to provide coolant in a gaseous state. An NG/coolant heat exchanger is arranged in connection with the LNG/coolant heat exchanger and is connected to the closed coolant loop. LNG is preheated within the LNG/coolant heat exchanger and NG is trim heated within the NG/coolant heat exchanger using liquid coolant from at least one heat exchanger.

A system for loading and storing CNG onboard of a ship and for unloading it therefrom comprises CNG loading facilities for loading CNG on board of the ship, CNG storage facilities for storing the loaded CNG on board of the ship at nominal storage pressure and temperature, and CNG unloading facilities for unloading CNG to a delivery point. The delivery point requires the unloaded CNG to be at delivery pressure and temperature generally different from the storage pressure and temperature. Thus, the CNG unloading facilities comprise a CNG heater for heating the to-be-unloaded CNG prior to unloading, and a lamination valve for allowing the to-be-unloaded CNG to expand from its storage pressure to the delivery pressure. A compressor may also be provided to compress CNG that would not otherwise be spontaneously delivered.

A liquid gas vaporization and measurement system, and associated method, for efficiently vaporizing a continuous sample of liquid gas, such as liquid natural gas (LNG), and accurately determining the constituent components of the gas. A constant flow of liquid gas sampled from a mass storage device is maintained in a vaporizing device. Within the vaporizing device the liquid gas is flash vaporized within heated narrow tubing. The liquid gas is converted to vapor very quickly as it enters one or more independently operating vaporizer stages within the vaporizing device. The vapor gas is provided to a measuring instrument such as a chromatograph and the individual constituent components and the BTU value of the gas are determined to an accuracy of within +/0.5 mole percent and 1 BTU, respectively.

Disclosed are a boil-off gas treatment system and method. The boil-off gas treatment system includes: a compressor compressing boil-off gas generated in a storage tank provided to a ship or a marine structure; a compressed gas heat exchanger disposed downstream of the compressor and performing heat exchange of the compressed boil-off gas with seawater or fresh water; and a boil-off gas heat exchanger disposed downstream of the compressed gas heat exchanger and performing heat exchanged of the compressed boil-off gas with boil-off gas to be supplied to the compressor.

A cold energy power generation system increases the efficiency in utilizing the cold exergy of liquefied gas while freely controlling the gas supply pressure on the outlet side of a secondary expansion turbine. The system includes a pressure-increasing pump for increasing the pressure of a low-temperature liquefied gas to a pre-overboost pressure while maintaining the liquid gas in a liquid state, a Rankine-cycle-type primary power generation apparatus, a heater for heating a vaporized gas, and a direct-expansion-type secondary power generation apparatus. Since the cold exergy of the liquefied gas is more efficiently utilized as pressure exergy than as temperature exergy, the system converts the cold exergy more preferentially to pressure exergy, and the optimal operating conditions that maximize the conversion efficiency can be determined by the composition of the liquefied gas, the temperature of the heating source, and the gas supply pressure.

The present invention relates to a system for CO.sub.2 storage, comprising a subsea CO.sub.2 storage unit having at least one inlet for receiving liquid CO.sub.2 and at least one outlet connected to at least one injection well in a subterranean reservoir, the subsea storage unit comprising at least one pipeline, the subsea storage unit being configured to contain and store CO.sub.2 and to transfer heat from the surrounding seawater to the contained CO.sub.2. The invention also relates to a method for CO.sub.2 storage.