System and method for enhanced argon recovery from a feed stream comprising hydrogen, methane, nitrogen and argon
AssigneePraxair Technology, Inc.
InventorHenry E. Howard
Life of this patent
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Abstract
A system and method for argon and nitrogen extraction from a feed stream comprising hydrogen, methane, nitrogen and argon, such as tail gas of an ammonia production plant is provided. The disclosed system and method provides for nitrogen-argon rectification and the methane rejection within a column system comprised of at least one distillation column. Nitrogen and argon are further separated and to produce liquid products. An argon stripping column arrangement is disclosed where residual argon is further removed from the methane-rich fuel gas and recycled back to the feed stream.
Claims17
A system for recovery of argon from a feed stream comprising hydrogen, nitrogen, methane and argon, the system comprising:
- a conditioning circuit configured for conditioning the feed stream to a temperature suitable for rectification and at pressure less than or equal to about 400 psia;
- at least one rectifying column configured to receive the conditioned feed stream and produce an argon depleted, nitrogen rich vapor stream, an argon enriched side draw, and a methane-rich liquid stream;
- an argon stripping column configured to receive the methane rich liquid stream and strip argon from the methane rich liquid stream using the argon depleted, nitrogen rich vapor stream and produce an argon depleted methane rich liquid from the bottom of the argon stripping column and an argon containing overhead gas from the top of the argon stripping column;
- a recycle circuit configured for extracting the argon containing overhead gas from the argon stripping column and mixing the argon containing overhead gas with the feed stream;
- and
- a distillation column arrangement configured to receive the argon enriched stream and produce a high purity argon stream and a nitrogen overhead gas stream.
A system for recovery of argon from a feed stream comprising hydrogen, nitrogen, methane and argon, the system comprising:
- a conditioning circuit configured for conditioning the feed stream to a temperature suitable for rectification and at pressure less than or equal to about 400 psia;
- at least one rectifying column configured to receive the conditioned feed stream and produce an argon depleted, nitrogen rich vapor stream, an argon enriched side draw, and a methane-rich liquid stream;
- a hydrogen stripping column configured to receive the argon enriched stream and strip hydrogen and methane from the argon enriched stream to produce a hydrogen and methane rejection gas stream and a hydrogen-free argon enriched stream;
- and
- a distillation column arrangement configured to receive the hydrogen-free argon enriched stream and produce a high purity argon stream and a nitrogen overhead gas stream.
Dependencies are inferred from the claim text.