Refrigeration – Cryogenic treatment of gas or gas mixture – Separation of gas mixture
Reexamination Certificate
2000-06-27
2001-12-11
Capossela, Ronald (Department: 1723)
Refrigeration
Cryogenic treatment of gas or gas mixture
Separation of gas mixture
C062S908000, C062S928000
Reexamination Certificate
active
06327872
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for producing a purified and pressurized liquid carbon dioxide stream in which a feed stream composed of carbon dioxide vapor is condensed into a liquid that is subsequently pressurized by being heated within a chamber. More particularly, the present invention relates to such a method and apparatus in which two chambers are used so that the pressurized liquid carbon dioxide stream can be continually dispensed.
Highly pressurized, purified liquid carbon dioxide is required for a variety of industrial processes. Such highly pressurized liquid is produced by purifying industrial grade liquid carbon dioxide that is available at about 13 to 23 bar and then pumping the liquid to a pressure of anywhere from between about 20 and about 68 bar.
The problem with pumping, however, is that impurities such as particulates or hydrocarbons can be introduced into the product stream as a byproduct of mechanical pump operation. As will be discussed, this problem is overcome in the present invention.
SUMMARY OF THE INVENTION
The present invention provides a method of producing a pressurized liquid carbon dioxide stream in which a feed stream composed of carbon dioxide vapor is introduced into a purifying filter. The purified feed stream is condensed within a condenser having a sump and an intermediate liquid stream is introduced from the condenser sump into first and second pressure accumulation chambers. The first and second pressure accumulation chamber are heated to pressurize liquid contained therein and the pressurized liquid carbon dioxide stream is delivered from the first and second pressure accumulation chambers.
The intermediate liquid stream is alternately introduced into the first and second pressure accumulation chambers and the pressurized liquid carbon dioxide stream is alternately delivered from the first and second pressure accumulation chambers such that prior to one of the first and second pressure accumulation chambers becoming empty, the intermediate liquid stream is introduced into the other of the first and second pressure accumulation chambers. This ensures continual delivery of the pressurized liquid carbon dioxide stream. Each of the first and second pressure accumulation chambers is vented to the sump of the condenser prior to introduction of the intermediate liquid stream therein.
Preferably, each of the first and second pressure accumulation chambers is electrically heated. Additionally, the feed stream is preferably condensed within the condenser through indirect heat exchange with a refrigerant stream. The pressurized liquid carbon dioxide stream can be further treated through its introduction into a particle filter.
In another aspect, the present invention provides an apparatus for producing a pressurized liquid carbon dioxide stream. In such aspect, a purifying filter is provided for purifying a feed stream composed of carbon dioxide vapor and a condenser having a sump is used for condensing the feed stream. First and second pressure accumulation chambers are associated with heaters for heating the first and second pressure accumulation chambers, thereby to pressurize liquid contained therein.
A flow network, associated with the pressure accumulation chambers, has conduits connecting the sump of the condenser to the first and second pressure accumulation chambers for discharging the pressurized liquid carbon dioxide stream therefrom. The flow network has valves associated with the conduits to allow for an intermediate liquid stream to be alternately introduced from the sump of the condenser into the first and second pressure accumulation chambers and the pressurized liquid carbon dioxide stream to be alternately delivered from the first and second pressure accumulation chambers such that prior to one of the first and second pressure accumulation chambers becoming empty, the intermediate liquid stream is introduced into the other of the first and second pressure accumulation chambers. This acts to ensure continual delivery of the pressurized liquid carbon dioxide. The conduits additionally include a vent line from the first and second pressure accumulation chambers to the condenser to allow each of the first and second pressure accumulation chambers to be vented prior to introduction of the intermediate liquid stream therein.
Preferably, the heaters comprise electrical heaters and the condenser includes an external refrigeration circuit having a heat exchanger to condense the feed stream through indirect heat exchange with a refrigerant stream. The apparatus can further comprise a particle filter connected to the flow network to filter the pressurized liquid carbon dioxide stream.
As may be appreciated from the above discussion, since heaters are used to pressurize the liquid, the liquid never contacts a mechanical pump component that could introduce impurities into the pressurized liquid carbon dioxide. Furthermore, since a pump is not used, maintenance requirements for an apparatus in accordance with the present invention are reduced over prior art devices.
REFERENCES:
patent: 3420633 (1969-01-01), Lee
patent: 4337071 (1982-06-01), Yang
patent: 4717406 (1988-01-01), Giacobbe
patent: 4806171 (1989-02-01), Whitlock et al.
patent: 5028273 (1991-07-01), Weltmer, Jr. et al.
patent: 5582029 (1996-12-01), Occhialini et al.
patent: 6164088 (2000-12-01), Moriguchi et al.
Boyd Robert Walter
Cheng David C.
Leitch Kelly
Pike Jessi Lynn
Capossela Ronald
Cohen Joshua L.
Pace Salvatore P.
The BOC Group Inc.
LandOfFree
Method and apparatus for producing a pressurized high purity... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for producing a pressurized high purity..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for producing a pressurized high purity... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2596330