Abstract: There is provided a process for the separation of a gaseous feed comprising a mixture of nitrogen, hydrocarbons and at least 0.005 mol % carbon dioxide, the process comprising: (i) cooling and at least partially condensing the gaseous feed, and (ii) separating in one or more stages the cooled and at least partially condensed gaseous feed into a hydrocarbon rich product stream low in nitrogen and a nitrogen rich reject stream low in hydrocarbons, and wherein refrigeration is provided to one or more stages of the separation process by a heat pump system in which a heat pump refrigerant fluid is compressed and subsequently expanded at one or more pressure levels below the condensing pressure, and subsequently heated in heat exchange with the gaseous feed and/or one or more streams generated by the separation process to provide refrigeration thereto; and further wherein at least part of the heated refrigerant is recycled through the heat pump system.

Abstract: The present application is concerned with processes and apparatuses for the separation of nitrogen from liquefied natural gas feeds. The processes comprise the steps of: (i) cooling the feed and passing the feed to a fractionation column; (ii) withdrawing from the fractionation column an overhead vapour stream having an enriched nitrogen content, and a liquid stream having a reduced nitrogen content; (iii) dividing the overhead vapour stream from step (ii) into at least first and second overhead streams; (iv) compressing, cooling and at least partially condensing at least the first overhead stream from step (iii); and (v) expanding the stream from step (iv) and passing the expanded stream to the fractionation column as reflux, and wherein cooling in step (iv) is provided, at least in part, by heat exchange with one or more streams from the fractionation column.

Abstract: The invention provides a process and apparatus for the separation of a gaseous feed comprising a mixture of hydrocarbons and nitrogen gas, the process comprising the steps of: (i) cooling and at least partially condensing the gaseous feed; (ii) feeding the cooled and at least partially condensed feed from step (i) to a fractionation column comprising reboil to produce an overhead hydrocarbon vapour stream enriched in nitrogen and a condensed hydrocarbon product stream low in nitrogen, wherein prior to the fractionation, the feed stream is divided into at least two streams including: a) a first stream which is expanded and fed to the fractionation column; b) a second stream which is expanded, heated and fed to a lower stage of the fractionation column than the first stream, (iii) removing a hydrocarbon product stream low in nitrogen from the fractionation column; and (iv) removing a hydrocarbon vapour stream enriched in nitrogen from the fractionation column.

Abstract: The invention provides a process and apparatus for the separation of nitrogen from a gaseous feed comprising a mixture of hydrocarbons and nitrogen gas, the process comprising the steps of: (i) cooling and at least partially condensing the gaseous feed; (ii) feeding the cooled and at least partially condensed feed from step (i) to a first fractionation to produce an overhead vapour stream having an enriched nitrogen content and a condensed product having a reduced nitrogen content which is subjected to a second fractionation, which comprises reboil, at a lower pressure than the first fractionation; (iii) partially condensing the overhead vapour stream, and separating to provide a liquid stream, which is used to provide reflux to the first fractionation, and a separated vapour stream, which is condensed to provide reflux to the second fractionation; and (iv) sub-cooling the condensed product of the first fractionation and dividing the resulting sub-cooled product into at least two streams: a first stream being

Abstract: A process is described for separating the heavier hydrocarbons from a gaseous hydrocarbon feed wherein a first separator is employed to separate partially condensed gaseous feed and wherein the vapour portion undergoes work expansion and is fed to a fractionation column. The liquid portion is subcooled in heat exchange with the overhead vapour from the fractionation column, expanded, evaporated to provide refrigeration at a low temperature level, and fed to the fractionation column. The rewarmed residual vapour is subsequently compressed to a pressure suitable for export, with a portion of the compressed gas being cooled, condensed and recycled back to reflux the top section of the fractionation column. Also described is a process wherein a first separator is employed to separate partially condensed gaseous feed and wherein the vapour portion undergoes work expansion and is fed to a high pressure wash column. The liquid portion is expanded and fed to the base of the high pressure wash column.

Abstract: A process is described for separating the heavier hydrocarbons from a gaseous hydrocarbon feed wherein a first separator is employed to separate partially condensed gaseous feed and wherein the vapour portion undergoes work expansion and is fed to a fractionation column. The liquid portion is subcooled in heat exchange with the overhead vapour from the fractionation column, expanded, evaporated to provide refrigeration at a low temperature level, and fed to the fractionation column. The rewarmed residual vapour is subsequently compressed to a pressure suitable for export, with a portion of the compressed gas being cooled, condensed and recycled back to reflux the top section of the fractionation column.