Refrigeration – Cryogenic treatment of gas or gas mixture – Separation of gas mixture
Reexamination Certificate
1999-03-05
2001-02-20
Capossela, Ronald (Department: 3744)
Refrigeration
Cryogenic treatment of gas or gas mixture
Separation of gas mixture
C062S644000
Reexamination Certificate
active
06189337
ABSTRACT:
This invention relates to an air separation apparatus.
Air separation apparatus employing a purifier for removing impurities such as water vapour and carbon dioxide from incoming compressed air, a heat exchanger for cooling the purified, compressed air to a temperature suitable for its separation by rectification, and at least one rectification or fractionation column for separating one or both of nitrogen and oxygen products from the air is well known.
Such air separation apparatus is, for example, used to provide high purity nitrogen to the electronics industry. The air separation apparatus may for this purpose take the form of any of the embodiments disclosed in EP-A-0 412 793 or EP-A-0 520 738.
There is often a need to supply to the same manufacturer of electronics components separate pure air and pure nitrogen products. Separate apparatuses are used for this purpose.
It is an aim of the present invention to provide a single apparatus which is able both to supply a product of air separation and purified air.
According to the present invention there is provided an air separation apparatus comprising a compressor having at least two stages in series, a first outlet from a chosen stage upstream of a final stage of the compressor, a second outlet from the final stage of the compressor, an air purifier having an inlet communicating with the first outlet and an outlet communicating with first and second flow paths in parallel with one another, wherein the first flow path leads via a heat exchanger to at least one rectification column for separating the air, there being an outlet for a nitrogen product from the said rectification column, the second flow path leads via the stage or stages downstream of said chosen stage to the second outlet, and the second outlet provides an outlet from the apparatus for a purified air product.
The apparatus according to the invention is thus able to provide a pure air product from the second outlet and at least one product of air separation from the rectification column least two such adsorbers in parallel. In a particularly preferred arrangement the air purifier is effective to remove water vapour, carbon dioxide and one or both of hydrogen and carbon monoxide impurities from the air.
The apparatus according to the invention typically additionally includes at least one expansion turbine for generating refrigeration for the separation of the air.
By employing a single air purifier and a single train of compressor stages in order to produce a product of air separation (for example nitrogen) and purified air, the invention makes possible a simplification of the known apparatus which requires separate compressors for both nitrogen and air production and separate air purifiers.
An apparatus according to the present invention will now be described by way of example only with reference to the accompanying drawing which is a schematic flow diagram of an air separation apparatus.
The drawing is not to scale.
REFERENCES:
patent: 2932174 (1960-04-01), Schilling
patent: 3477239 (1969-11-01), Rische
patent: 3950957 (1976-04-01), Zakon
patent: 4459143 (1984-07-01), Nawata et al.
patent: 5425240 (1995-06-01), Jain et al.
patent: 542539 A1 (1993-05-01), None
patent: 0653599 A1 (1995-05-01), None
Capossela Ronald
Pace Salvatore P.
The BOC Group plc
LandOfFree
Air separation apparatus 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 apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Air separation apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2612602