Chemistry of hydrocarbon compounds – Purification – separation – or recovery – By plural serial diverse separations
Patent
1992-10-28
1995-08-22
McFarland, Anthony
Chemistry of hydrocarbon compounds
Purification, separation, or recovery
By plural serial diverse separations
585853, 585867, 62 19, 62 23, C07C 700, F25J 300
Patent
active
054441765
ABSTRACT:
A safe, effective, and economical method is provided for recovering olefins from cat-cracked gases without accumulating dangerous amounts of nitrogen oxides. A stream of cat-cracked gas first is scrubbed to remove acid gases, including nitrogen dioxide (NO.sub.2), and then is passed through a depropanizer fractionation tower. Hydrocarbons having four or more carbon atoms are recovered in the bottoms of the depropanizer, and the overhead from the depropanizer--which is composed of hydrocarbons having three or fewer carbon atoms--is sent to an absorber demethanizer tower. Hydrocarbons having two or more carbon atoms are recovered in the bottoms from the absorber demethanizer tower, where temperatures are no lower than about -45.56.degree. C. (-50.degree. F.). The overhead from the absorber demethanizer tower--which is composed of methane, hydrogen, and trace amounts of nitrogen oxide, C.sub.2, and absorbent (C.sub.3)--then is chilled to condense and recover trace amounts of C.sub.2 and heavier gases, including trace amounts of the C.sub.3 absorbent, at temperatures of about -101.11.degree. C. (-150.degree. F.) or higher. Thus, recovery of desired hydrocarbons from the cat-cracked gas is conducted at temperatures that are high enough to prevent the oxidation of nitric oxide (NO) to form nitrogen dioxide (NO.sub.2) and high enough to prevent the accumulation of unwanted nitrogen oxides.
REFERENCES:
patent: 2573341 (1951-10-01), Kniel
patent: 3485886 (1969-12-01), Mitchell et al.
patent: 3607963 (1971-09-01), Dannell et al.
patent: 3635038 (1972-01-01), Nagel et al.
patent: 4743282 (1988-05-01), Mebra
patent: 5220097 (1993-06-01), Lam et al.
Grenoble Dane C.
Halle Roy T.
Thomson William D.
Exxon Chemical Patents Inc.
McFarland Anthony
Phan Nhat D.
Russell Linda K.
LandOfFree
Process for recovering olefins from cat-cracked gas without accu does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for recovering olefins from cat-cracked gas without accu, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for recovering olefins from cat-cracked gas without accu will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2142742