Abstract: A process for liquefying natural gas in conjunction with processing natural gas to recover natural gas liquids (NGL) is disclosed. In the process, the natural gas stream to be liquefied is taken from one of the streams in the NGL recovery plant and cooled under pressure to condense it. A distillation stream is withdrawn from the NGL recovery plant to provide some of the cooling required to condense the natural gas stream. The condensed natural gas stream is expanded to an intermediate pressure and supplied to a mid-column feed point on a distillation column. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas, and is routed to the NGL recovery plant so that these heavier hydrocarbons can be recovered in the NGL product.

Abstract: A process for liquefying natural gas in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane is disclosed. In the process, the natural gas stream to be liquefied is partially cooled, expanded to an intermediate pressure, and supplied to a distillation column. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas. The residual gas stream from the distillation column is compressed to a higher intermediate pressure, cooled under pressure to condense it, and then expanded to low pressure to form the liquefied natural gas stream.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. In recent years, the preferred method of separating a hydrocarbon gas stream generally includes supplying at least portions of the gas stream to a fractionation tower having at least one reboiler, and often one or more side reboilers, to supply heat to the column by withdrawing and heating some of the tower liquids to produce stripping vapors that separate the more volatile components from the desired components. The reboiler and side reboilers (if any) are typically integrated into the feed stream cooling scheme to provide at least a portion of the refrigeration needed to condense the desired components for subsequent fractionation in the distillation column.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. In recent years, the preferred method of separating a hydrocarbon gas stream generally includes supplying at least portions of the gas stream to a fractionation tower having at least one reboiler, and often one or more side reboilers, to supply heat to the column by withdrawing and heating some of the tower liquids to produce stripping vapors that separate the more volatile components from the desired components. The reboiler and side reboilers (if any) are typically integrated into the feed stream cooling scheme to provide at least a portion of the refrigeration needed to condense the desired components for subsequent fractionation in the distillation column.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. In recent years, the preferred method of separating a hydrocarbon gas stream generally includes supplying at least a portion of the gas stream to a work expansion device, then directing the work expanded stream to a distillation column at a mid-column feed point below an upper rectification section. The top column feed above the upper rectification section is typically a condensed and subcooled gaseous stream, frequently comprised of a gas stream that would otherwise feed the work expansion device. In the process disclosed, the work expanded stream is further cooled prior to feeding the distillation column at the mid-column feed point, so that a lesser volume of top column feed is required to maintain the column overhead temperature at a temperature whereby the major portion of the desired components is recovered.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is divided into first and second streams, and the second stream is cooled and expanded to a lower pressure and supplied to a contacting device. The first stream is cooled to condense substantially all of it, expanded to the lower pressure, and then used to cool a warmer distillation stream from a distillation column to at least partially condense the distillation stream. At least a portion of the partially condensed distillation stream is directed to the contacting device to intimately contact the expanded second stream, the resulting vapors and liquids are separated from the contacting device, and these liquids are supplied to the distillation column.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is divided into first and second streams, and the second stream is expanded to the fractionation tower pressure and supplied to the column at a mid-column feed position. A recycle stream is withdrawn from the tower overhead after it has been warmed and compressed, and is combined with the first stream. The combined stream is cooled to condense substantially all of it, and is thereafter expanded to the fractionation tower pressure and supplied to the fractionation tower at a top column feed position. The pressure of the compressed recycle stream and the quantities and temperatures of the feeds to the column are effective to maintain the column overhead temperature at a temperature whereby the major portion of the desired components is recovered.

Abstract: A process for the recovery of propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is cooled and/or expanded to partially condense it, then separated to provide one or more C.sub.3 containing liquid steams and a first vapor stream. These streams are then directed into a distillation column wherein a second vapor stream is separated to recover a product containing the major portion of the C.sub.3 components and heavier hydrocarbon components. A distillation stream is withdrawn from the column below the feed point of the first vapor stream and is then directed into heat exchange relation with the second vapor stream to cool the distillation stream and condense at least a part of it, forming a condensed stream. At least a portion of the condensed stream is directed to the distillation column as its top feed.

Abstract: A process for the recovery of propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is cooled and/or expanded to partially condense it, then separated to provide a first vapor stream. The first vapor stream is directed into a contacting device whereby a third vapor stream and a C.sub.3 -containing liquid stream are formed. The C.sub.3 -containing liquid stream is directed to a distillation column wherein a second vapor stream is separated to recover a product containing the major portion of the C.sub.3 components and heavier hydrocarbon components. The second vapor stream is directed into heat exchange relation with the third vapor stream to cool the second vapor stream and condense at least a part of it, forming a condensed stream.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is divided into first and second streams. The first stream is cooled to condense substantially all of it and is thereafter expanded to the fractionation tower pressure and supplied to the fractionation tower at a first mid-column feed position. The second stream is expanded to the tower pressure and is then supplied to the column at a second mid-column feed position. A recycle stream is withdrawn from the tower overhead after it has been warmed and compressed. The compressed recycle stream is cooled sufficiently to substantially condense it, and is then expanded to the pressure of the distillation column and supplied to the column at a top column feed position.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is cooled to partially condense it, then separated to provide a first vapor stream and a first condensed stream. The first vapor stream is divided into first and second streams, then the first stream is combined with the first condensed stream. The combined stream is cooled and expanded to an intermediate pressure to partially condense it, then separated to provide a second vapor stream and a second condensed stream. The second vapor stream is cooled at the intermediate pressure to condense substantially all of it and is thereafter expanded to the fractionation tower pressure and supplied to the fractionation tower at a top feed position. The second condensed stream is subcooled at the intermediate pressure, expanded to the tower pressure, and is supplied to the column at a first mid-column feed position.

Abstract: A process for the recovery of C.sub.2 components (ethylene and/or ethane) and heavier hydrocarbon components from a gas stream containing a significant quantity of components more volatile than methane (e.g., hydrogen, nitrogen, and/or others) is disclosed. The cooled, partially condensed hydrocarbon bearing gas stream is separated into a vapor containing substantial quantities of the component(s) more volatile than methane and a liquid containing predominantly hydrocarbons. The vapor is expanded to the distillation column pressure and then supplied to the column at an upper mid-column feed position. The liquid is expanded to column pressure and supplied to the column at a lower mid-column feed position. A recycle stream is withdrawn from the column at a point below the upper mid-column feed position where the bulk of the volatile components are supplied to the column.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbons from a liquefied natural gas (LNG) stream is disclosed. At least a portion of the LNG feed stream is directed in heat exchange relation with a compressed recycle portion of the fractionation tower overhead, with the warmed LNG stream thereafter supplied to the fractionation tower at a mid-column feed position. The recycle stream is cooled by the LNG stream sufficiently to substantially condense it, and the substantially condensed recycle stream is then supplied to the column at a top column feed position to serve as reflux for the tower. The pressure of the recycle stream and the quantities and temperatures of the feeds to the column are effective to maintain the column overhead temperature at a temperature whereby the major portion of said desired components is recovered in the bottom liquid product from the column.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is divided into first and second streams. The first stream is cooled to condense substantially all of it and is thereafter expanded to the fractionation tower pressure. After expansion, the cooled first stream is directed in heat exchange relation with a compressed recycle portion of the fractionation tower overhead. The warmed first stream is then supplied to the fractionation tower at a first mid-column feed position. The second stream is expanded to the tower pressure and is then supplied to the column at a second mid-column feed position. The recycle stream is cooled by the first stream sufficiently to substantially condense it. The substantially condensed recycle stream is then expanded to the pressure of the distillation column and supplied to the column at a top column feed position.

Abstract: A process for the recovery of ethane and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is divided into first and second streams. The first stream is cooled to condense substantially all of it and is thereafter expanded to a pressure below that of the distillation column. After expansion, the cooled first stream is directed in heat exchange relation with a warmer distillation stream rising from fractionation stages of the distillation column. The warmed first stream is then separated to provide a cold vapor and a liquid stream. The liquid is supplied to the column at a first mid-column feed position and the cold vapor is supplied to the column at a second mid-column feed position. The second stream is expanded to the column pressure and is then supplied to the column at a third mid-column feed position. The distillation stream is cooled by the first stream sufficiently to partially condense it .

Abstract: A process for the recovery of propane and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is divided into first and second streams. The first stream is cooled to condense substantially all of it and is thereafter expanded to the pressure of the distillation column. After expansion, the cooled first stream is directed in heat exchange relation with a warmer distillation stream rising from fractionation stages of the distillation column. The warmed first stream is then supplied to the column at a first mid-column feed position. The second stream is expanded to the column pressure and is then supplied to the column at a second mid-column feed position. The distillation stream is cooled by the first stream sufficiently to partially condense it. The partially condensed distillation stream is then separated to provide volatile residue gas and a reflux stream. The reflux stream is supplied to the column at a top column feed position.