A method for operating a natural gas liquids processing (NGL) system, the system being selectively configured in either an ethane rejection configuration or an ethane recovery configuration, the method comprising, when the NGL system is in the ethane rejection configuration, collecting a reboiler bottom stream that, in the ethane rejection configuration, includes ethane in an amount of less than 5% by volume, and when the NGL system is in the ethane recovery configuration, collecting a reboiler bottom stream that, in the ethane recovery configuration, includes ethane in an amount of at least about 30% by volume.

Methods and systems for separating components are disclosed. A process liquid stream is provided that contains a first component and a second component. The process liquid stream is cooled to near a temperature at which the second component forms a solid. The process liquid stream is expanded into a vessel such that the first component and a first portion of the second component vaporize to form a process vapor stream and a second portion of the second component forms a solid to form a solid product stream. The process vapor stream and the solid product stream are passed out of the vessel.

Implementations described and claimed herein provide systems and methods for removing nitrogen during liquefaction of natural gas. In one implementation, a nitrogen rejection unit is used in an LNG facility to remove nitrogen from natural gas during an LNG liquefaction process. The nitrogen rejection unit contains at least two columns and at least one 3-stream condenser, 2-stream condenser or a two 2-stream condenser.

Implementations described and claimed herein provide systems and methods for removing nitrogen during liquefaction of natural gas. In one implementation, a nitrogen rejection unit is used in an LNG facility to remove nitrogen from natural gas during an LNG liquefaction process. The nitrogen rejection unit contains at least two columns and at least one 3-stream condenser, 2-stream condenser or a two 2-stream condenser.

Embodiments provide a method for preventing shutdowns in LNG facilities by removing heavy hydrocarbons from the inlet gas supply. According to an embodiment, there is provided an LNG facility treating pipeline quality natural gas that is contaminated with lubrication oil and low concentrations of heavy hydrocarbons. Due to contamination, the behavior of the pipeline quality natural gas is not properly predicted by thermodynamic modeling. In an embodiment, heavy hydrocarbons are removed by a drain system in a heat exchanger. In an embodiment, heavy hydrocarbons are removed by a treatment bed.