Back to results
US 5,711,166 AGranted
Air separation method and apparatus
AssigneeThe BOC Group, Inc.
InventorsAnish Mehta, Sidney Simon Stern
Life of this patent
Estimating the term…
Abstract
A method and apparatus of separating air in which the air is rectified wig a single column nitrogen generator which produces a nitrogen stream which is expanded into a refrigerant stream and then taken as a medium pressure product. Oxygen enriched air can be taken as low pressure and medium pressure enriched air products. A stream of oxygen enriched air can be used to regenerate the pre-purification unit and also taken as a wet product.
Claims6
A method of separating air, said method comprising:
- filtering, compressing, and purifying the air to produce a compressed and purified air stream;
- cooling the compressed and purified air stream to a temperature suitable for its rectification;
- rectifying the air contained within said compressed and pad fled air stream within a single column nitrogen generator to produce gaseous nitrogen as a tower overhead and oxygen enriched liquid as a column bottoms;
- valve expanding a coolant stream composed of said oxygen enriched liquid;
- producing reflux for said nitrogen generator by condensing part of a stream of said gaseous nitrogen against vaporizing said coolant stream;
- partially warming a remaining part of said stream of gaseous nitrogen;
- expanding said remaining part of said stream of gaseous nitrogen with the performance of work to produce a refrigerant stream;
- indirectly exchanging heat between said refrigerant stream and said coolant stream, directly after vaporization thereof, with said with the compressed and purified air stream so that said compressed and purified air stream is cooled to said temperature suitable for its rectification and said refrigerant stream and said coolant stream fully warm;
- and
- taking as products said coolant and said refrigerant streams.
7 more elements
An apparatus for separating air, said apparatus comprising:
- means for producing a compressed and purified air stream;
- a single column nitrogen generator for rectifying the air contained within said compressed and purified air stream to produce said gaseous nitrogen as a tower overhead and oxygen enriched liquid as a column bottoms;
- a valve connected to said single column nitrogen generator for valve expanding a coolant stream composed of said oxygen enriched liquid;
- a head condenser connected to said nitrogen generator and configured to condense part of a stream of the gaseous nitrogen against vaporizing said coolant stream, thereby to produce reflux for said single column nitrogen generator;
- expansion means for expanding a remaining part of said stream of gaseous nitrogen with the performance of work to produce a refrigerant stream;
- and
- main heat exchange means directly connected to said head condenser to directly receive said coolant stream after the vaporization thereof, interposed between said single column nitrogen generator, said expansion means and said compressed and purified air stream producing means, and configured for cooling the compressed and purified air stream to a temperature suitable for its rectification, for partially warming the remaining part of the stream of the gaseous nitrogen and for fully warming said refrigerant stream and for fully warming said coolant stream.
4 more elements
Dependencies are inferred from the claim text.