An air-sparged hydrocyclone for separating a vapor from a carrier gas is disclosed. The cyclone comprises a porous sparger covered by an outer gas plenum. A cryogenic liquid is injected to a tangential feed inlet at a velocity that induces a tangential flow and a cyclone vortex in the air-sparged hydrocyclone. The carrier gas is injected into the cyclone through the porous sparger. The vapor dissolves, condenses, desublimates, or a combination thereof, forming a vapor-depleted carrier gas and a vapor-enriched cryogenic liquid. The vapor-depleted carrier gas is drawn through a vortex finder and the vapor-enriched cryogenic liquid is drawn through an apex nozzle outlet. In this manner, the vapor is removed from the carrier gas.

The system is provided for generating a mixed methane gas feed stream using at least one source of biogas and an alternate source of methane gas. The system includes a biogas subsystem, a control device for the methane gas from the at least one alternate source of methane gas, and a vertically-extending gas mixing vessel. A method of controlling a methane gas mass flow rate of a mixed methane gas feed stream is also disclosed. The proposed concept is particularly well adapted for situations where an uninterrupted and relatively constant input of methane gas is required to ensure an optimum operation of, for instance, a LMG production plant.

A marine vessel and method for carbon capture and sequestration are described. The marine vessel includes a buoyant hull, a cryogenic storage tank within the hull, and a gaseous carbon dioxide loading manifold. The marine vessel also includes a carbon dioxide liquefaction system in fluid communication with the cryogenic storage tank downstream of the carbon dioxide liquefaction system and with the gaseous carbon dioxide loading manifold upstream of the carbon dioxide liquefaction system. Finally, the marine vessel includes a carbon dioxide supercritical system in fluid communication with the cryogenic storage tank. In operation, the marine vessel moves between multiple locations, where gaseous carbon dioxide is onboarded, liquified and stored. Thereafter, the marine vessel transports the liquified carbon dioxide to a location adjacent an offshore geological reservoir. The liquefied carbon dioxide is then pressurized to produce supercritical carbon dioxide, which is then injected directly into the reservoir from the marine vessel.

Oxidative dehydrogenation is an alternative to the energy extensive steam cracking process presently used for the production of olefins from paraffins. Various embodiments of an oxidative dehydrogenation chemical complex designed to allow removal of sulfur containing contaminants that collect in the gas mixer unit and in the feed lines leading to the ODH reactor are disclosed herein.

A system and method for cooling and liquefying a gas in a heat exchanger that includes compressing and cooling a mixed refrigerant using first and last compression and cooling cycles so that high pressure liquid and vapor streams are formed. The high pressure liquid and vapor streams are cooled in the heat exchanger and then expanded so that a primary refrigeration stream is provided in the heat exchanger. The mixed refrigerant is cooled and equilibrated between the first and last compression and cooling cycles so that a pre-cool liquid stream is formed and subcooled in the heat exchanger. The stream is then expanded and passed through the heat exchanger as a pre-cool refrigeration stream. A stream of gas is passed through the heat exchanger in countercurrent heat exchange with the primary refrigeration stream and the pre-cool refrigeration stream so that the gas is cooled. A resulting vapor stream from the primary refrigeration stream passage and a two-phase stream from the pre-cool refrigeration stream passage exit the warm end of the exchanger and are combined and undergo a simultaneous heat and mass transfer operation prior to the first compression and cooling cycle so that a reduced temperature vapor stream is provided to the first stage compressor so as to lower power consumption by the system. Additionally, the warm end of the cooling curve is nearly closed further reducing power consumption. Heavy components of the refrigerant are also kept out of the cold end of the process, reducing the possibility of refrigerant freezing, as well as facilitating a refrigerant management scheme.

A hydrocyclone for separating a vapor from a carrier gas is disclosed. The hydrocyclone comprises one or more nozzles. A cryogenic liquid is injected to a tangential feed inlet at a velocity that induces a tangential flow and a cyclone vortex in the hydrocyclone. The carrier gas is injected into the cryogenic liquid, causing the vapor to dissolve, condense, desublimate, or a combination thereof, forming a vapor-depleted carrier gas and a vapor-enriched cryogenic liquid. The vapor-depleted carrier gas is drawn through a vortex finder and the vapor-enriched cryogenic liquid is drawn through an apex nozzle outlet. In this manner, the vapor is removed from the carrier gas.

Embodiments described herein provide methods and systems for separating a mixed ethane and CO.sub.2. A method described includes generating a liquid stream including ethane and CO.sub.2. The liquid stream is flashed to form an ethane vapor stream and solid CO.sub.2. The solid CO.sub.2 is accumulated in an accumulation vessel and the gas is removed from the top of the accumulation vessel.

The present invention relates to methods of increasing the operability, capacity, and efficiency of natural gas liquefaction processes, with a focus on mixed refrigerant cycles. The present invention also relates to natural gas liquefaction systems in which the above-mentioned methods can be carried out. More specifically, a refrigerant used in a pre-cooling heat exchanger of a natural gas liquefaction plant is withdrawn from the pre-cooling heat exchanger, separated into liquid and vapor streams in a liquid-vapor separator after being cooled and compressed. The vapor portion is further compressed, cooled, and fully condensed, then returned to the liquid-vapor separator. Optionally, the fully condensed stream may be circulated through a heat exchanger before being returned to the liquid-vapor separator for the purpose of cooling other streams, including the liquid stream from the liquid-vapor separator.

A flare recovery method includes receiving a flare gas inlet stream that has C.sub.1-C.sub.8 hydrocarbons. The flare gas inlet stream is separated in a recovery column to produce a C.sub.1-C.sub.2 hydrocarbon stream and a C.sub.3-C.sub.8 hydrocarbon stream. The C.sub.3-C.sub.8 hydrocarbon stream is separated in a separation column to produce a C.sub.3 hydrocarbon stream and a C.sub.4-C.sub.8 hydrocarbon stream. The C.sub.4-C.sub.8 hydrocarbon stream is transported to a location for blending with crude oil. The C.sub.3 hydrocarbon stream is optionally recovered as a saleable product or is combined with the C.sub.1-C.sub.2 hydrocarbon stream to produce a flare gas stream.

A method for separating a vapor from a carrier gas is disclosed. A hydrocyclone is provided with one or more nozzles on the wall of the hydrocyclone. A cryogenic liquid is provided to the tangential feed inlet at a velocity that induces a tangential flow and a cyclone vortex in the hydrocyclone. The carrier gas is injected into the hydrocyclone through the one or more nozzles. The vapor dissolves, condenses, desublimates, or a combination thereof, forming a vapor-depleted carrier gas and a vapor-enriched cryogenic liquid. The vapor-depleted gas is drawn through the vortex finder while the vapor-enriched cryogenic liquid is drawn through the apex nozzle outlet. In this manner, the vapor is removed from the carrier gas.