CRYOGENIC SYSTEM FOR REMOVING ACID GASES FROM A HYDROCARBON GAS STREAM, AND METHOD OF REMOVING ACID GASES

摘要

A system for removing acid gases from a raw gasstream the system includes a cryogenic distillation tower. The towerreceives and separates the raw gas stream into an overhead methanestream and a bottom liquefied acid gas stream. Refrigeration equipmentdownstream of the cryogenic distillation tower cools the overheadmethane stream and returns a portion of the overhead methanestream to the cryogenic distillation tower as liquid reflux. The systemalso may include a first molecular sieve bed upstream of thedistillation tower and a second molecular sieve bed downstream ofthe distillation tower. The first molecular sieve bed adsorbs waterwhile the second molecular sieve bed adsorbs additional acid gasesfrom the cooled overhead methane stream.