US4908121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible feed pyrolysis process
Assignee: MW KELLOGG COMPANY (A DE CORP FORMED IN 1987)
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Filing: 1986-05-12
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Granted: 1990-03-13
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Expires: 2006-05-12
Abstract
Abstract When steam cracking hydrocarbons to lower olefins in a tubular fired furnace having a convection section for preheating hydrocarbon feed, feedstock flexibility to process light feeds is provided by cooling mixed feed of steam and hydrocarbon followed by reheating to the desired mixed feed temperature.
Inventors
- 👤 Larry G. Hackemesser
- 👤 Bradley L. Lankford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:29
CPC Classifications
C; C10; C10G; C10G9/00; C10G9/34; C10G9/36; C10G9/14
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
88 words
A process for steam cracking hydrocarbons in a tubular, fired furnace having a convection section for preheating the hydrocarbons and a radiant section for cracking the preheated hydrocarbons which comprises: (a) preheating an initial hydrocarbon feed in the convection section; (b) mixing diluent steam with the resulting preheated, initial hydrocarbon feed to form a mixed feed; (c) cooling the mixed feed; (d) reheating the cooled mixed feed in the convection section; and (e) cracking the reheated mixed feed containing all the initial hydrocarbon feed in the radiant section.
Claim 2
Dependent Claim
88 words
A process for steam cracking hydrocarbons in a tubular, fired furnace having a convection section for preheating the hydrocarbons and a radiant section for cracking the preheated hydrocarbons which comprises: (a) preheating an initial hydrocarbon feed in the convection section; (b) mixing diluent steam with the resulting preheated, initial hydrocarbon feed to form a mixed feed; (c) cooling the mixed feed; (d) reheating the cooled mixed feed in the convection section; and (e) cracking the reheated mixed feed containing all the initial hydrocarbon feed in the radiant section.
Claim 3
Dependent Claim
17 words
The process of claim 1 wherein the mixed feed is cooled by direct heat exchange with water.
Claim 4
Dependent Claim
15 words
The process of claim 1 wherein the mixed feed is cooled by indirect heat exchange.
Claim 5
Dependent Claim
19 words
The process of claim 1 wherein the mixed feed is cooled by direct heat exchange with a hydrocarbon coolant.
Claim 6
Dependent Claim
35 words
The process of claim 4 wherein an initial hydrocarbon feed is preheated in the convection section to form the preheated, initial hydrocarbon feed and the hydrocarbon coolant is a portion of the initial hydrocarbon feed.
Claim 7
Dependent Claim
29 words
The process of claim 1 wherein the preheated, initial hydrocarbon feed is a normally gaseous hydrocarbon and the mixed feed is cooled by from 55° C. to 220° C.
Claim 8
Dependent Claim
50 words
The process of claim 1 wherein the preheated, initial hydrocarbon feed is a normally liquid hydrocarbon having an initial boiling point between 25° C. and 120° C. and an end point between 150° C. and 230° C. and the mixed feed is cooled by from 55° C. to 140° C.
Claim 9
Dependent Claim
19 words
The process of claim 6 wherein the cooled mixed feed is reheated to from 565° C. to 705° C.
Claim 10
Dependent Claim
19 words
The process of claim 7 wherein the cooled mixed feed is reheated to from 540° C. to 650° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-12 | 1993-09-11 | 1994-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-12 | 1997-09-11 | 1998-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-12 | 2001-09-11 | 2002-03-13 | $7700.00 | Window Closed / Lapsed |