The invention is directed to a combined naphtha hydrotreating (NHT) and isomerization process scheme, which includes dividing wall columns (DWC) that replace multiple distillation columns and allow optimized heat integration within the system. The disclosed design provides reductions in both capital and energy costs compared to conventional schemes.

The invention is directed to a combined naphtha hydrotreating (NHT) and isomerization process scheme, which includes dividing wall columns (DWC) that replace multiple distillation columns and allow optimized heat integration within the system. The disclosed design provides reductions in both capital and energy costs compared to conventional schemes.

Systems and methods for crude oil separations including degassing, dewatering, desalting, and stabilization. One method includes separating crude oil into a crude oil off-gas and a partially degassed crude oil output; compressing the crude oil off-gas; applying the compressed crude oil off-gas for indirect heating through reboilers of the partially degassed crude oil output; and directly mixing with the crude oil a compressed atmospheric pressure gas. In some embodiments, multiple reboilers are used. In some embodiments, heat exchangers are used. Aftercoolers are used after the compressor to cool the gas; knockout drums are used after the coolers to separate liquids.

Systems and methods for crude oil separations including degassing, dewatering, desalting, and stabilization. One method includes separating crude oil into a crude oil off-gas and a partially degassed crude oil output; compressing the crude oil off-gas; applying the compressed crude oil off-gas for indirect heating through reboilers of the partially degassed crude oil output; and directly mixing with the crude oil a compressed atmospheric pressure gas. In some embodiments, multiple reboilers are used. In some embodiments, heat exchangers are used. Aftercoolers are used after the compressor to cool the gas; knockout drums are used after the coolers to separate liquids.

A system and method to remove gas, water, and salt from crude oil via a GOSP train and discharging the crude oil from a desalter vessel of the GOSP train as unstabilized crude oil to a stabilizer distillation column, removing gas from the unstabilized crude oil via the stabilizer distillation column to reduce vapor pressure of the unstabilized crude oil to give stabilized crude oil, and diverting a bypass portion of the unstabilized crude oil discharged from the desalter vessel to the stabilized crude oil downstream of the stabilizer distillation column.

A system and method to remove gas, water, and salt from crude oil via a GOSP train and discharging the crude oil from a desalter vessel of the GOSP train as unstabilized crude oil to a stabilizer distillation column, removing gas from the unstabilized crude oil via the stabilizer distillation column to reduce vapor pressure of the unstabilized crude oil to give stabilized crude oil, and diverting a bypass portion of the unstabilized crude oil discharged from the desalter vessel to the stabilized crude oil downstream of the stabilizer distillation column.

An isomerization method consists of a deisobutanizer column receives feed comprising n-butane. The deisobutanizer column delivers its bottoms a portion to a reboiler and another portion along with hydrogen is routed to a isomerization reactor and the reactor effluent is returned to the column. A stabilizer which is integrated with the column, an overhead stream used as a reflux and bottoms containing an iso-butane-rich stream that is the iso-butane product stream. The column overhead effluent is routed to separator, which splits the hydrocarbons and effluent, where the hydrocarbons are routed to deisobutanizer column and effluent recycled to stabilizer, where the stabilizer separates the reactor effluent into product streams contains an iso-butane product stream, a n-butane product stream, and a lighter hydrocarbon product stream.

An isomerization method consists of a deisobutanizer column receives feed comprising n-butane. The deisobutanizer column delivers its bottoms a portion to a reboiler and another portion along with hydrogen is routed to a isomerization reactor and the reactor effluent is returned to the column. A stabilizer which is integrated with the column, an overhead stream used as a reflux and bottoms containing an iso-butane-rich stream that is the iso-butane product stream.

The column overhead effluent is routed to separator, which splits the hydrocarbons and effluent, where the hydrocarbons are routed to deisobutanizer column and effluent recycled to stabilizer, where the stabilizer separates the reactor effluent into product streams contains an iso-butane product stream, a n-butane product stream, and a lighter hydrocarbon product stream.

A system and method to remove gas, water, and salt from crude oil via a GOSP train and discharging the crude oil from a desalter vessel of the GOSP train as unstabilized crude oil to a stabilizer distillation column, removing gas from the unstabilized crude oil via the stabilizer distillation column to reduce vapor pressure of the unstabilized crude oil to give stabilized crude oil, and diverting a bypass portion of the unstabilized crude oil discharged from the desalter vessel to the stabilized crude oil downstream of the stabilizer distillation column.

A system and method to remove gas, water, and salt from crude oil via a GOSP train and discharging the crude oil from a desalter vessel of the GOSP train as unstabilized crude oil to a stabilizer distillation column, removing gas from the unstabilized crude oil via the stabilizer distillation column to reduce vapor pressure of the unstabilized crude oil to give stabilized crude oil, and diverting a bypass portion of the unstabilized crude oil discharged from the desalter vessel to the stabilized crude oil downstream of the stabilizer distillation column.