A method for loading liquefied nitrogen (LIN) into a cryogenic storage tank initially containing liquid natural gas (LNG) and a vapor space above the LNG. First and second nitrogen gas streams are provided. The first nitrogen stream has a lower temperature than the second nitrogen gas stream. While the LNG is offloaded from the storage tank, the first nitrogen gas stream is injected into the vapor space. The storage tank is then purged by injecting the second nitrogen gas stream into the storage tank to thereby reduce a natural gas content of the vapor space to less than 5 mol %. After purging the storage tank, the storage tank is loaded with LIN.

A process for producing an olefin having N carbon atoms is proposed in which using a dehydrogenation a process gas is formed which contains at least the olefin having N carbon atoms, a paraffin having N carbon atoms and a hydrocarbon having N1 carbon atoms and in which using at least a portion of the process gas a separation input is formed which is subjected to a low temperature separation in which the separation input is cooled stepwise over a plurality of temperature levels and condensates are separated from the separation input, wherein the condensates are at least partly subjected to a first low temperature rectification to obtain a first gas fraction and a first liquid fraction, wherein the first gas fraction contains at least the olefin having N carbon atoms in a lower proportion than in the condensates and the hydrocarbon having N1 in a higher proportion than in the condensates. It is provided that the first gas fraction is at least partly subjected to a second low temperature rectification using a liquid reflux containing predominantly or exclusively the hydrocarbon having N1 carbon atoms in which the first gas fraction undergoes depletion in the olefin having N carbon atoms. A corresponding plant (100) likewise forms part of the subject matter of the invention.

Methods and systems for removing moisture from refrigerant that use a desiccant-based moisture removal unit can be used in the production of liquid natural gas (LNG). For example, a method can include: compressing a refrigerant; conveying at least a portion of the refrigerant to a moisture removal unit comprising a desiccant to form dehydrated refrigerant; cooling and condensing the dehydrated refrigerant to provide a cooled dehydrated liquid refrigerant; conveying the cooled dehydrated refrigerant to a heat exchanger; and passing a LNG stream rich in methane through the heat exchanger to cool at least part of the LNG stream by indirect heat exchange with the cooled dehydrated refrigerant.

A reliquefaction system and process for innovative reliquefaction of LNG boil-off gas (BOG), where the reliquefaction is propelled by LNG gas fuel. The reliquefaction system is preferably installed on shipboard including LNG carrier or harbor tug, where the LNG carrier and harbor tug use a gas fuel engine.

This method comprises passing a residual stream into a flash drum to form a gaseous overhead flow and liquid bottom flow, and feeding the bottom flow into a distillation column,

It comprises cooling the overhead flow in a heat exchanger to form a cooled overhead flow.

It comprises the extraction of a gaseous overhead stream at the head of the distillation column, and the formation of at least one effluent stream from the overhead stream and/or from the top stream.

The separation of the cooled overhead flow flow comprises passing the cooled overhead flow into an absorber, and injecting a methane-rich stream into the absorber to place the cooled overhead flow in contact with the methane-rich stream.

A gas separation and utilization method includes the steps of: (a) providing an ascending flow of a liquid containing carbon dioxide gas and methane gas; (b) extracting at least a fraction of the methane gas from the liquid to provide a methane enriched gas; (c) extracting at least a fraction of the carbon dioxide gas from the liquid to provide a carbon dioxide enriched gas, which is extracted from the ascending flow of the liquid downstream of the methane enriched gas; (d) collecting the methane enriched gas; (e) feeding the carbon dioxide enriched gas as a fuel into an oxyfuel power generation system; (f) generating power from the oxyfuel power generation system; and (g) expelling an exhaust from the oxyfuel power generation system, wherein the exhaust comprises carbon dioxide and water vapor. A system configured to perform the method and a grid balancing method using the system are also disclosed.

A method for removing heavy hydrocarbons from a feed gas by: feeding, into an absorber, a top reflux stream and a second reflux stream below the top reflux stream, wherein the absorber produces an absorber bottom product stream and an absorber overhead product stream; depressurizing and feeding the absorber bottom product stream to a stripper to produce a stripper bottom product stream and a stripper overhead product stream; cooling and feeding a portion of the absorber overhead product stream back to the absorber as the top reflux stream; and pressurizing and feeding the stripper overhead stream back to the absorber as the second reflux stream. A system for carrying out the method is also provided.

A method for loading liquefied nitrogen (LIN) into a cryogenic storage tank initially containing liquid natural gas (LNG) and a vapor space above the LNG. First and second nitrogen gas streams are provided. The first nitrogen stream has a lower temperature than the second nitrogen gas stream. While the LNG is offloaded from the storage tank, the first nitrogen gas stream is injected into the vapor space. The storage tank is then purged by injecting the second nitrogen gas stream into the storage tank to thereby reduce a natural gas content of the vapor space to less than 5 mol %. After purging the storage tank, the storage tank is loaded with LIN.

A method and apparatus for recovering carbon dioxide (CO2) from an oxyfuel combustion engine exhaust stream is described. The method comprises: providing and separating an oxyfuel combustion engine exhaust stream to provide a first liquefied CO2 stream and a first waste gas stream; condensing at least a portion of the first waste gas stream to provide a partly condensed waste gas stream; and separating the condensed waste gas stream to provide a second waste gas stream, and a second liquefied CO2 stream.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.