Air separation

Details Air separation Air separation

1991-07-11

1992-09-15

Capossela, Ronald C.

Refrigeration

Processes

Circulating external gas

62 39, F25J 302

Patent

active

051467569

ABSTRACT:
An air stream is compressed in a compressor, and purified in an apparatus. A major portion of the compressed, purified air stream is then cooled in a main heat exchanger to a temperature suitable for its separation in a double rectification column comprising a higher pressure column and a lower pressure column. The lower pressure column typically operates at a pressure in the range of 2.5 to 4.5 bar. A minor portion of the compressed, purified air stream is employed to generate refrigeration for the air separation by being further compressed in the compressor and expanded in a turbine. Oxygen and nitrogen product streams are withdrawn from the lower pressure column. The nitrogen product stream is passed through the main heat exchanger countercurrently to the major air stream. A part of this nitrogen stream is withdrawn at an intermediate region of the heat exchanger and is expanded in an expansion turbine. The resulting expanded nitrogen passes through the heat exchanger from its cold to its warm end thereby creating additional refrigeration so as to maintain a mean temperature different from end to end of the heat exchanger of at least 10K between the streams being warmed and the streams being cooled. A substantial reduction in the size of the heat exchanger compared with that of a conventional plant thereby becomes possible. The expanded nitrogen stream leaving the warm end of the heat exchanger may also be used to perform a cooling duty at about ambient temperature.

REFERENCES:
patent: 4222756 (1960-09-01), Thorogood
patent: 4367082 (1983-01-01), Tomisaka et al.
patent: 4372764 (1983-02-01), Theobald
patent: 4790866 (1988-12-01), Rathbone

Affiliated with

Also associated with

Rating

Air separation does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Air separation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Air separation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-729670