Refrigeration – Cryogenic treatment of gas or gas mixture – Separation of gas mixture
Patent
1997-12-08
1999-11-30
Doerrler, William
Refrigeration
Cryogenic treatment of gas or gas mixture
Separation of gas mixture
F25J 302
Patent
active
059921757
ABSTRACT:
The present invention is directed to methods for improving the efficiency and economy of processes for the recovery of natural gas liquids (NGL) from a gas feed, e.g., raw natural gas or a refinery or petrochemical plant gas stream. These methods may be employed with most, if not all, conventional separation methods using a distillation tower, e.g., a demethanizer or deethanizer column. In the methods of the present invention, a portion of a hydrocarbon liquid condensed on a chimney tray disposed below the lowest feed tray of the column is withdrawn from the tower. This withdrawn liquid hydrocarbon is expanded and heated to produce a two-phase system for separation into a heavy, liquid hydrocarbon product and a vapor phase for recycle to the column, preferably as a stripping gas. The withdrawn hydrocarbon liquid is preferably heated by indirect heat exchange with the inlet gas, thus reducing or eliminating the external refrigeration requirements of the process. The expanded, heated vapor recycled to the column increases the ethane and propane concentration in the column, thus reducing the tray temperature profile and increasing the separation efficiency. Accordingly, the column may be operated at lower temperatures and higher pressures, resulting in significant energy savings and economies of operation.
REFERENCES:
patent: 3592015 (1971-07-01), Streich et al.
patent: 4171964 (1979-10-01), Campbell et al.
patent: 4251249 (1981-02-01), Gulsby
patent: 4278457 (1981-07-01), Campbell et al.
patent: 4318723 (1982-03-01), Holmes et al.
patent: 4350511 (1982-09-01), Holmes et al.
patent: 4596588 (1986-06-01), Cook
patent: 4617038 (1986-10-01), Mehra
patent: 4680042 (1987-07-01), Mehra
patent: 4687499 (1987-08-01), Aghili
patent: 4690702 (1987-09-01), Paradowski et al.
patent: 4692179 (1987-09-01), Mehra
patent: 4698081 (1987-10-01), Aghili
patent: 4851020 (1989-07-01), Montgomery, IV
patent: 4885063 (1989-12-01), Andre
patent: 5275005 (1994-01-01), Campbell et al.
patent: 5421165 (1995-06-01), Paradowski et al.
patent: 5566554 (1996-10-01), Vijayaraghavan et al.
patent: 5588306 (1996-12-01), Schmidt
patent: 5600969 (1997-02-01), Low
patent: 5737940 (1998-04-01), Yao et al.
patent: 5779863 (1998-07-01), Ha et al.
Chen Jong Juh
Elliot Douglas G.
Yao Jame
Bushman Browning
Doerrler William
IPSI LLC
LandOfFree
Enhanced NGL recovery processes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Enhanced NGL recovery processes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Enhanced NGL recovery processes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1658399