A system for increasing the efficiency of heating cryogenic fluid flowing in a downstream direction through a fluid conduit includes a heating mechanism, an upstream valve, a downstream valve, and a controller. The heating mechanism heats the cryogenic fluid, resulting in conversion of a portion of the cryogenic fluid into a buoyant flow moving in an upstream direction. The upstream valve is located upstream of the heating mechanism and controls an upstream-valve mass flow rate of the cryogenic fluid. The downstream valve is located downstream of the heating mechanism and controls a downstream-valve mass flow rate of the cryogenic fluid. The controller adjusts the upstream valve to a choked position at which: an upstream-valve non-buoyant mass flow rate substantially matches the downstream-valve mass flow rate, and the upstream valve at least partially blocks the buoyant flow from flowing in the upstream direction past the upstream valve.

Draining a cryogenic storage vessel to remove a pump is timing consuming, expensive and can result in increased greenhouse gas emissions. A cryogenic storage vessel comprises an inner vessel defining a cryogen space and an outer vessel spaced apart from and surrounding the inner vessel, defining a thermally insulating space between the inner and outer vessels. A receptacle comprises an outer sleeve and an inner sleeve, and defines passages for delivery of liquefied gas from the cryogen space to outside the cryogenic storage vessel. The outer sleeve intersects opposite sides of the inner vessel, with the opposite ends of the outer sleeve defining an interior space in fluid communication with the thermally insulating space that is sealed from the cryogen space. The inner sleeve has an open end supported from the outer vessel, and extends into the interior space defined by the outer sleeve, and a closed end opposite the open end, defining a receptacle space that is fluidly isolated from the thermally insulating space. A fluid communication channel extends from the cryogen space to the receptacle space, and can be selectively closed to allow the pump to be removed.

A CO.sub.2 energy storage system includes a storage tank that stores a CO.sub.2 slurry, including dry ice and liquid CO.sub.2, at CO.sub.2 triple point temperature and pressure conditions. The storage system also includes a first pump coupled in flow communication with the storage tank. The first pump is configured to receive the CO.sub.2 slurry from the storage tank and to increase a pressure of the CO.sub.2 slurry to a pressure above the CO.sub.2 triple point pressure. The energy storage system further includes a contactor coupled in flow communication with the first pump. The contactor is configured to receive the high pressure CO.sub.2 slurry from the pump and to receive a first flow of gaseous CO.sub.2 at a pressure above the CO.sub.2 triple point pressure. The gaseous CO.sub.2 is contacted and then condensed by the melting dry ice in the slurry to generate liquid CO.sub.2.

A vessel for the transport of liquefied gas has a hull, a cargo storage tank arranged in the hull for storing liquefied gas and an engine to propel the ship. A compressor has a compressor inlet connected to a vapour space of the at least one cargo storage tank for receiving boil-off gas at a first pressure and a compressor outlet for supplying pressurized boil-off gas to the at least one engine at a second pressure exceeding the first pressure. A boil-off gas recovery system is provided for recovery of boil off gas. The boil-off gas recovery system has a cooling section with a cooling section inlet connected to the compressor outlet to recondense at least part of the pressurized boil-off gas and a boil-off gas storage tank having a boil-off gas storage tank inlet connected to the cooling section outlet for storing the recondensed pressurized boil-off gas.

The present invention relates to a method for removing helium from a pressurized container, wherein supercritical helium is removed from the pressurized container; wherein the removed supercritical helium is actively cooled by means of a cooling device and/or passively cooled by means of a Joule-Thomson expansion; and thereby at least partially forms liquid helium.

A multi-stage gas compression system useful at the production site and at central collection points, having an energy efficient and effective intercooler system. The system includes a reciprocating compressor having a plurality of compressor valves and cylinders configured in series to provide staged compression to the natural gas. Coupled with the compressor are an inlet port for receiving natural gas to be compressed, and an outlet port for delivering compressed fluid from the compressor to a discharge line, to the transmission pipeline or storage. Facilitating transmission and intercooling of the natural gas between cylinders are a plurality of pipes, each pipe in close proximity with an intercooler. The rate of cooling of the intercooler is determined by a control system coupled therewith, including a temperature sensor positioned within pipe proximal to the intercooler, and means to compare the temperature measured by the temperature sensor and an optimal temperature or temperature range, and determine appropriate levels of cooling provided by the intercooler.

The invention relates to a method for adjusting a hydrogen outlet temperature at a filling station, comprising inter alia a liquid reservoir (1), a cryopump (2), a heat exchanger (6), a gas reservoir (11) and a mixing point (7), wherein a cold hydrogen stream and a warm hydrogen stream are intermixed such that the temperature at the mixing point (7) lies between 30 and 45 C.

Apparatus and methods for vaporizing LNG while producing sufficient volume of compressed natural gas at sufficient pressure to meet the needs of internal combustion engines, gas turbines, or other high consumption devices operating on natural gas or on a mixture of diesel and natural gas. The LNG vaporizer of the present invention incorporates a reciprocating pump to provide vaporized LNG to an output at rates and pressures as required by the particular application. The heat rejected into the engine coolant and the exhaust stream from an artificially loaded internal combustion engine, as well as the hydraulic heat resulting from artificially loading the engine, is transferred to the LNG as the LNG passes through a heat exchanger. Exhaust heat is transferred to the engine coolant after the coolant passes through the heat exchanger.

A method and system are provided for operating refueling station tube-trailers and compressors to reduce hydrogen refueling cost. A hydrogen refueling station includes a two-tier fuel supply of pressure vessels on a refueling station tube-trailer, with a first tier and a second tier of pressure vessels including at least one or more pressure vessels connected together. A separate control unit is coupled to the first tier and the second tier of pressure vessels with each of the control units coupled to a compressor. The compressor is coupled to a high pressure buffer storage by a separate control unit. In operation, pressure is monitored in the each tier. Hydrogen is consolidated selectively between the first tier of pressure vessel banks, the second tier pressure vessels, and the high pressure buffer. Based upon monitored pressures, one of the first tier of pressure vessels, the second tier pressure vessel banks, and the high pressure buffer is used to refuel vehicles.

A cryotank that includes an inner tank for receiving a medium stored in the cryotank; an outer container enclosing the inner tank; an insulation space arranged between the inner tank and the outer container; a first heat exchanger arranged outside the inner tank and the outer container; an extraction device for the medium, the extraction device having at least one extraction line arranged in the insulation space to facilitate conveying of the medium out of the inner tank to the first heat exchanger; and a recirculation line back arranged in the insulation space in thermal contact with the at least one extraction line to facilitate conveying a recirculation partial flow back into the inner tank and an extraction partial flow downstream of the first heat exchanger to a consumer.