Process for producing ultra high purity oxygen
AssigneeAir Products and Chemicals, Inc.
InventorsThomas E. Cormier, Bruce K. Dawson, Keith B. Wilson, Thomas C. Young
Life of this patent
Estimating the term…
Abstract
A method of oxygen recycle on the bottom section of the low-pressure column of a dual-pressure column, with an increase in the bottom section reboil vapor rate, allows an appreciable increase in the production rate of ultra high purity oxygen and a substantial decrease in power required as compared to conventional processes.
Claims13
In a method for the production of ultra high purity oxygen by means of liquefying and fractionally distilling air in a dual-column air separation plant having a high-pressure column and a low-pressure column, the improvement for reducing the net energy requirement comprising the steps of:
- removing an oxygen-rich vapor stream from a first intermediate level of the low-pressure column,
- compressing the vapor stream,
- condensing the compressed vapor stream to liquid in an auxiliary low-pressure column reboiler,
- flashing the condensed liquid stream to the pressure of the low-pressure column to form a stream of a gas and liquid mixture,
- returning the flashed stream to a second intermediate level of the low-pressure column.
In a method for the production of ultra high purity oxygen by means of liquefying and fractionally distilling air in a dual-column air separation plant having a high-pressure column and a low-pressure column, the improvement for reducing the net energy requirement comprising the steps of:
- removing an oxygen-rich vapor stream from a first intermediate level of the low-pressure column,
- heating the vapor stream to ambient temperature,
- compressing the heated vapor stream followed by cooling in an after-cooler,
- cooling the compressed vapor stream by heat exchange against said vapor stream as it leaves the low-pressure column,
- condensing the cooled vapor stream to liquid in an auxiliary low-pressure column reboiler,
- flashing the condensed liquid stream to the pressure of the low-pressure column to form a stream of a gas and liquid mixture,
- returning the flashed stream to a second intermediate level of the low-pressure column.
Dependencies are inferred from the claim text.