ARGON CONDENSATION SYSTEM AND METHOD

摘要

An argon reflux condensation system and method in which a plurality of once-through condensers are connected to an argon column of an air separation plant to condense argon-rich vapor streams for production of reflux to the argon column. Condensation of the argon-rich vapor streams is brought about through indirect heat exchange with crude liquid oxygen streams that partially vaporize and are introduced into a lower pressure column of the plant for further refinement. The flow rate of the crude liquid oxygen streams are sensed and controlled at locations in the air separation plant where the crude liquid oxygen is in a liquid state and in proportion to the size of the once-through heat exchangers. Prior to flowing into the once-through condensers, the partially vaporized crude oxygen stream enters a phase separator which separates the crude oxygen vapor from the crude liquid oxygen. The separated crude oxygen vapor bypasses the once-through condensers and is mixed with the vaporized oxygen stream that exits the one-through condensers. Feed stream flow rate to the argon column is controlled in response to air flow rate to the plant and product flow rate is controlled in response to the feed stream flow rate to the argon column.

主权项

1. An argon condensation system for an air separation unit having an argon column, a lower pressure column and a higher pressure column, said argon condensation system comprising:
a plurality of once-through heat exchangers connected to an argon column such that argon-rich vapor streams composed of argon-rich vapor column overhead are condensed within condensation passages of the once-through heat exchangers to produce an argon-rich liquid product stream and an argon-rich liquid reflux stream that is returned to the argon column as reflux; a phase separator configured to separate a partially vaporized crude oxygen feed stream into at least one crude oxygen vapor stream and one or more crude liquid oxygen streams, wherein the partially vaporized crude oxygen feed stream originates as a crude liquid oxygen column bottoms from the higher pressure column that is partially vaporized as it is directed to the phase separator; one or more crude liquid oxygen feed conduits disposed between the phase separator and vaporization passages of the once-through heat exchangers and configured to direct the one or more crude liquid oxygen streams to the plurality of once-through heat exchangers and wherein the one or more crude liquid oxygen streams are partially vaporized in the vaporization passages of the once-through heat exchangers through indirect heat exchange with the argon-rich vapor streams to produce partially vaporized crude liquid oxygen streams; and one or more crude oxygen vapor conduits disposed between the phase separator and the lower pressure column and configured to direct the at least one crude oxygen vapor stream from the phase separator to the lower pressure column; wherein the argon-rich vapor column overhead is produced through distillation of a crude argon feed stream and is fed from the lower pressure column to the argon column.