Method for olefin production from butanes and cracking refinery hydrocarbons and alkanes
View Patent ↗Systems and processes for producing one or more olefins are provided. A feed containing C 4 compounds can be dehydrogenated to provide a first product containing butene. At least a portion of the first product can be bypassed around a methyl-tert-butyl-ether production unit and cracked in a first cracker to provide a second product containing propylene, ethylene, and butane. A light hydrocarbon containing gas oils, full range gas oils, resid or any combination thereof can be cracked in a second cracker to provide a cracked hydrocarbon containing propylene, ethylene, and butane. An alkane can be cracked in a third cracker to provide cracked alkanes containing propylene, ethylene, and butane. The second product, cracked hydrocarbons, and cracked alkanes can be combined and separated to provide a third product containing propylene and a first recycle containing butane. At least a portion of the first recycle can be recycled to the first product prior to cracking. At least a portion of the first recycle can be recycled to feed prior to dehydrogenation.
1. A process for making propylene, comprising:
dehydrogenating a feed comprising butane to provide a first product comprising butene;
bypassing the first product around an etherification reactor for converting isobutylene to methyl tert-butyl ether;
cracking at least a portion of the first product in a first cracker to provide a second product comprising propylene, ethylene, and butane;
cracking a refinery hydrocarbon comprising gas oil, full range gas oil, resid, or a combination thereof in a second cracker to provide a cracked hydrocarbon comprising ethylene, propylene, or a combination thereof;
cracking one or more alkanes in a third cracker to provide an effluent comprising ethylene and propylene;
combining the second product, cracked hydrocarbon, and effluent to form a mixture;
selectively separating at least a portion of the mixture to provide a third product comprising propylene and a first recycle comprising butane; and
recycling at least a portion of first recycle to the first product.
2. The process of claim 1 , wherein the first product is heated to a temperature of about 90° C. to about 370° C.
3. The process of claim 1 , wherein cracking at least a portion of the first product occurs at a temperature of about 590° C. to about 675° C., and a pressure of about 40 kPa to about 700 kPa.
4. The process of claim 1 , wherein the feed comprises a mixture having from about 40% to about 95% by weight paraffins having 4 or more carbon atoms and about 5% to about 60% by weight olefins having 4 or more carbon atoms.
5. The process of claim 1 , wherein the first product comprises a mixture having from about 40% to about 95% by weight olefins having 4 or more carbon atoms and about 5% to about 60% by weight paraffins having 4 or more carbon atoms.
6. The process of claim 1 , wherein the first cracker is a fluidized catalytic cracker having a catalyst-to-first product ratio of about 5:1 to about 70:1.
7. The process of claim 1 , wherein the second product exits the first cracker at a temperature of from about 550° C. to about 650° C. when the first product comprises at least 90% by weight hydrocarbons having 4 carbon atoms.
8. A process for making propylene, comprising:
dehydrogenating a feed comprising butane to provide a first product comprising butene;
bypassing the first product around an etherification reactor for converting isobutylene to methyl tert-butyl ether;
cracking at least a portion of the first product in a first cracker to provide a second product comprising propylene, ethylene, and butane;
cracking a refinery hydrocarbon comprising gas oil, full range gas oil, resid, or a combination thereof in a second cracker to provide a cracked hydrocarbon comprising ethylene, propylene, or a combination thereof;
cracking one or more alkanes in a third cracker to provide an effluent comprising ethylene and propylene;
combining the second product, cracked hydrocarbon, and effluent to form a mixture;
selectively separating at least a portion of the mixture to provide a third product comprising propylene and a first recycle comprising butane;
recycling at least a portion of the first recycle to the first product; and
recycling at least a portion of the first recycle to the feed.
9. The process of claim 8 , wherein cracking at least a portion of the first product occurs at a temperature of about 590° C. to about 675° C., and a pressure of about 40 kPa to about 700 kPa.
10. The process of claim 8 , wherein the feed comprises a mixture having from about 40% to about 95% by weight paraffins having 4 or more carbon atoms and about 5% to about 60% by weight olefins having 4 or more carbon atoms.
11. The process of claim 8 , wherein the first product comprises a mixture having from about 40% to about 95% by weight olefins having 4 or more carbon atoms and about 5% to about 60% by weight paraffins having 4 or more carbon atoms.
12. The process of claim 8 , wherein the first cracker is a fluidized catalytic cracker having a catalyst-to-first product ratio of about 5:1 to about 70:1.
13. The process of claim 8 , wherein the second product stream exits the first cracker at a temperature of from about 550° C. to about 650° C. when the first product comprises at least 90% by weight hydrocarbons having 4 carbon atoms.
14. A process for retrofitting a methyl tert-butyl ether process, comprising:
bypassing a first product produced by dehydrogenating a feed comprising butane around an etherification reactor for converting isobutylene to methyl tert-butyl ether, wherein the first product comprises butene;
cracking at least a portion of the first product in a first cracker to provide a second product comprising propylene, ethylene, and butane;
cracking a refinery hydrocarbon comprising gas oil, full range gas oil, resid, or a combination thereof in a second cracker to provide a cracked hydrocarbon comprising ethylene, propylene, or a combination thereof;
cracking one or more alkanes in a third cracker to provide an effluent comprising ethylene and propylene;
combining the second product, cracked hydrocarbon, and effluent to form a mixture;
selectively separating at least a portion of the mixture to provide a third product comprising propylene and a first recycle comprising butane; and
recycling at least a portion of first recycle to the first product.
15. The process of claim 14 , wherein the first product is heated to a temperature of about 90° C. to about 370° C.
16. The process of claim 14 , wherein cracking at least a portion of the first product occurs at a temperature of about 590° C. to about 675° C., and a pressure of about 40 kPa to about 700 kPa.
17. The process of claim 14 , wherein the feed comprises a mixture having from about 40% to about 95% by weight paraffins having 4 or more carbon atoms and about 5% to about 60% by weight olefins having 4 or more carbon atoms.
18. The process of claim 14 , wherein the first product comprises a mixture having from about 40% to about 95% by weight olefins having 4 or more carbon atoms and about 5% to about 60% by weight paraffins having 4 or more carbon atoms.
19. The process of claim 14 , wherein the first cracker is a fluidized catalytic cracker having a catalyst-to-first product ratio of about 5:1 to about 70:1.
20. The process of claim 14 , wherein the second product stream exits the first cracker at a temperature of from about 550° C. to about 650° C. when the first product comprises at least 90% by weight hydrocarbons having 4 carbon atoms.
21. The process of claim 1 , wherein the feed further comprises isobutane and has an isobutane concentration of about 50% vol to about 99% vol.
22. The process of claim 1 , wherein the feed further comprises about 70% vol or more isobutane and about 5% vol to about 30% vol butane.
23. The process of claim 1 , wherein the first product further comprises isobutane, isobutene, hydrogen, and C 1 to C 3 hydrocarbons, and the process further comprises:
contacting at least a portion of the first product with a solvent to provide a solvent mixture; and
separating the solvent mixture to produce a purified isobutane/isobutene mixture, wherein the purified isobutane/isobutene mixture contains less hydrogen and C 1 to C 3 hydrocarbons than the first product, and wherein at least a portion of the purified isobutane/isobutene mixture is cracked in the first cracker to provide the second product.
24. The process of claim 1 , wherein the feed further comprises about 70% vol or more isobutane and about 5% vol to about 30% vol butane, wherein the first product further comprises isobutene and isobutane and has an isobutane to isobutene molar ratio ranging from about 1:1 to about 1.5:1, and wherein the first recycle further comprises isobutane and has a concentration of isobutane of about 5% vol to about 20% vol and a concentration of butane of about 20% vol to about 80% vol.
25. The process of claim 1 , wherein selectively separating at least a portion of the mixture further provides a C 7 and heavier product, and the process further comprises hydrotreating the C 7 and heavier product to provide a treated gasoline product.
26. The process of claim 25 , further comprising:
selectively separating the treated gasoline product to provide an aromatic-rich product comprising about 40 wt % or more aromatics and an aromatic-lean product comprising less than about 30 wt % aromatics;
recycling at least a portion of the aromatic-lean product to the third cracker; and
recycling at least a portion of the aromatic-rich product to the first cracker.
27. The process of claim 1 , wherein selectively separating at least a portion of the mixture further provides a second recycle and an third recycle, wherein the second recycle comprises about 90 mol % or more propane and the third recycle comprises about 90 mol % or more ethane, and the process further comprises recycling at least a portion of the second recycle and at least portion of the third recycle to the third cracker.
28. The process of claim 1 , wherein selectively separating at least a portion of the mixture further provides a methane recycle comprising about 70 mol % or more methane, and the process further comprises recycling at least a portion of the methane recycle to the first cracker.
29. The process of claim 1 , further comprising recycling at least a portion of the third product to the first cracker.
30. The process of claim 1 , wherein the third product comprises abut 80 mol % or more propylene, and the process further comprises recycling about 10% vol or more of the third product to the first cracker.