Claims
- 1. A process of relieving downstream burdens and fouling in a resid hydrotreating unit, said method comprising the steps of:
- (a) hydrotreating a resid feed stream in at least one ebullated bed reactor;
- (b) feeding a high temperature heavy oil liquid component from said reactor to a high temperature flash drum;
- (c) feeding a liquid output of said high temperature flash drum to a solvent extraction unit without further distillative fractionation to separate said output into asphaltenes, resins, and oils;
- (d) recycling a portion of said resins separated in step (c) to an input of said ebullated bed reactor of step (a); and
- (e) forwarding a portion of said oils separated in step (c) for further processing in a fluid catalytic cracking unit or a catalytic feed hydrotreating unit.
- 2. The process of claim 1 and the added steps of feeding medium and low temperature heavy oil liquid components from said reactor to medium and low temperature flash drums, respectively; and feeding liquid outputs of said medium and low temperature flash drums to an atmospheric tower for separation into liquid fractions.
- 3. The process of claim 2 wherein said liquids fractions separated in said atmospheric tower include naphtha, distillates, and gas oil.
- 4. The process of claim 1 wherein the separation of step (c) comprises the added steps of:
- (c1) feeding said high temperature component from an output of said flash drum and a solvent into a first stage solvent separator;
- (c2) feeding an asphaltene-rich phase from said first stage solvent separator; and
- (c3) feeding an asphaltene-depleted phase from said first stage solvent separator to at least one second stage solvent separator.
- 5. The process of claim 4 wherein there are three of said solvent separator stages and the added step of taking said oils separated in step (c) from a bottom of a third solvent separator, and of recycling solvent withdrawn from said third stage separator to an input of said first stage separator of step (c1).
- 6. The process of claim 5 and the added step of exchanging heat between said recycled solvent and said asphaltene-depleted phase fed to said second separator in step (c3).
- 7. The process of claim 1 wherein said high temperature heavy oil liquid component is separated from a reactor effluent stream by a high temperature separator operating in the approximate range of about 700.degree. F.-850.degree. F.
- 8. The process of claim 7 wherein the separator operates in the approximate range of about 2500-2900 psia.
- 9. The process of claim 1 wherein a solvent extraction unit solvent is a C.sub.3 -C.sub.5 alkane, or mixtures thereof.
- 10. A resid hydrotreating process comprising the steps of:
- (a) hydrotreating an input resid feedstream in an ebullated bed reactor to produce an output stream;
- (b) separating said output stream into high temperature, medium temperature, and low temperature heavy oil liquid components;
- (c) feeding each of said components to individually associated high, medium, and low temperature flash drums, respectively;
- (d) without further distillative fractionation feeding a liquid output of said high temperature flash drum to a solvent extraction unit; and
- (e) feeding liquid outputs form said medium and low temperature flash drums to an atmospheric tower for separation into at least naphtha, distillates, and gas oil.
- 11. The process of claim 10 and the added steps of: separating said liquid output of said high temperature flash drum into asphaltenes, resins, and oil.
- 12. The process of claim 11 and the added step of eliminating said asphaltenes separated in said solvent extractor unit of step (d).
- 13. The process of claim 11 and the added step of recycling said resin into said input feed stream of said ebullated bed reactor.
- 14. The process of claim 10 wherein step (e) includes the steps of separating said medium and low temperature components in said atmospheric tower into unstable naphtha, heavy naphtha, light distillate, mid-distillates, light atmospheric gas oil, and heavy gas oil.
- 15. The process of claim 11 wherein the separation of step (d) comprises the added steps of:
- (d1) feeding said output of said high temperature flash drum and a solvent into a first stage solvent separator;
- (d2) feeding an asphaltene-rich phase from said first stage separator;
- (d3) feeding an asphaltene-depleted phase from said first stage separator to at least one second stage solvent separator; and
- (d4) withdrawing resins from said second stage separator and recycling the resins to said ebullated bed reactor.
- 16. The process of claim 15 wherein there are three of said solvent separator stages in said solvent extractor unit and the added step of taking oils separated in step (d) from a bottom of third stage solvent separator, and of recycling a solvent phase from a top of said third stage solvent separator to an input of said first stage separator of step (1).
- 17. The process of claim 16 and the added step of exchanging heat between said recycled solvent and said asphaltene-depleted phase fed from said first stage separator to said second separator.
- 18. The process of claim 10 wherein said high temperature heavy oil liquid component is separated from a reactor effluent stream by a high temperature separator operating in the approximate range of about 700.degree. F.-850.degree. F.
- 19. The process of claim 18 wherein the separator operates in the approximate range of about 2500-2900 psia.
- 20. The process of claim 10 wherein a solvent extraction unit solvent is a C.sub.3 -C.sub.5 alkane, or mixtures thereof.
- 21. A process for use in a resid hydrotreating unit, said process comprising the steps of:
- (a) separating a high temperature heavy oil liquid component of a partially refined liquid output stream of an ebullated bed resid hydrotreating reactor, said separated high temperature component containing at least some bottom materials;
- (b) feeding said high temperature component of said partially refined output stream to a high temperature flash drum;
- (c) feeding an effluent liquid stream form said flash drum to a solvent extractor unit without further distillative fractionation to separate the stream into asphaltenes, resins, and oils; and
- (d) recycling said separated resins to an input of said ebullated bed reactor to eventually rejoin said partially refined oil stream of step (a).
- 22. The process of claim 21 wherein said high temperature component is separated from said liquid output stream in a high temperature separator operating in the approximate range of about 700.degree. F.-850.degree. F.
- 23. The process of claim 22 wherein the separator operates in the approximate range of about 2500-2900 psia.
- 24. The process of claim 21 wherein a solvent extraction unit solvent is a C.sub.3 -C.sub.5 alkane, or mixtures thereof.
- 25. A resid hydrotreating unit process comprising the steps of:
- (a) feeding a condensable effluent partially refined resid from a medium and low temperature flash system through an atmospheric tower for fractionating it into lighter components;
- (b) feeding a high temperature liquid effluent from partially refined resid from a high temperature flash system to a solvent extraction unit without further distilling the liquid effluent; and
- (c) extracting heavier components from a liquid effluent produced by said high temperature flash system, said extraction being carried out by a solvent extraction process locate upstream of said atmospheric tower whereby said resid hydrotreating unit is relieved of a bottleneck in said refining because the extracted heavier components do not reach and foul the atmospheric tower.
- 26. A hydrotreating process comprising the steps of:
- (a) substantially desalting crude oil;
- (b) heating said desalted crude oil in a pipestill furnace;
- (c) pumping said heated crude oil to a primary distillation tower;
- (d) separating said heated crude oil in said primary distillation tower into streams of naphtha, kerosene, primary gas oil, and primary reduced crude oil;
- (e) pumping said primary reduced crude oil to a pipestill vacuum tower;
- (f) separating said primary gas oil in said pipestill vacuum tower into streams of wet gas, heavy gas oil, and vacuum reduced crude oil providing resid oil;
- (g) feeding a resid oil feed comprising solvent-extracted resins and said resid oil from said pipestill vacuum tower to a resid hydrotreating unit comprising a series of three ebullated bed reactors;
- (h) injecting hydrogen-rich gases into said ebullated bed reactors;
- (i) conveying resid hydrotreating catalysts to said ebullated bed reactors;
- (j) ebullating said feed comprising said solvent-extracted resins and said resid oil with said hydrogen-rich gases in the presence of said resid hydrotreating catalyst in said ebullated bed reactors under hydrotreating conditions to produce upgraded hydrotreated resid oil;
- (k) feeding a high temperature component from an output of said ebullated bed reactor to a high temperature flash drum and liquid effluent from said high temperature flash drum without further distillative fractionation to a first stage solvent separator;
- (l) feeding a bottom material from said first stage solvent separator to a solid fuels unit or a coker;
- (m) feeding a top material of said first stage solvent separator to at least one second stage solvent separator;
- (n) feeding a top material from said second stage solvent to a third stage solvent separator;
- (o) withdrawing separated asphaltenes from a bottom of said first stage solvent separator and separated resins from a bottom of said second stage separator;
- (p) conveying said solvent-extracted resins from said solvent extraction unit of step (o) to said resid hydrotreating unit as part of said resid oil feed;
- (q) withdrawing separated oils from a bottom of said third solvent separator, and recycling solvent withdrawn from said third stage separator to an input of said first stage separator;
- (r) feeding medium and low temperature components from said ebullated bed reactor to medium and low temperature flash drums, respectively; and feeding liquid outputs of said medium and low temperature flash drums to an atmospheric tower for separation into liquid fractions, said liquid fractions separated in said atmospheric tower include naphtha, distillates, and gas oil;
- (s) separating virgin atmospheric tower bottom material in a resid vacuum tower into vacuum streams of vacuum gas oil and vacuum tower bottoms comprising vacuum resid oil;
- (t) conveying and feeding a substantial portion of said vacuum tower bottoms from said resid vacuum tower to a resid hydrotreating unit.
- 27. The process of claim 26 and the added steps of:
- (u) feeding a solvent to said multistage solvent extraction unit of step (t), said solvent comprising a member selected from the group consisting of butane and pentane;
- (v) substantially deasphalting and solvent-extracting said vacuum tower bottoms with said solvent in said multistage solvent extraction unit to substantially separate said vacuum tower bottoms into streams of substantially deasphalted solvent-oil, substantially deasphalted solvent-extracted resins, and substantially deresined solvent-extracted asphaltenes;
- (w) recovering said solvent under supercritical conditions and recycling said solvent to said solvent extraction unit of step (t); and
- (x) transporting at least some of said solvent-extracted asphaltenes of step (v) for use as solid fuel.
- 28. A hydrotreating process comprising the steps of:
- (a) feeding a first stream comprising resid to a reactor;
- (b) feeding a second stream comprising recycled substantially deasphalted resins to said reactor;
- (c) feeding hydrotreating catalyst to said reactor;
- (d) injecting hydrogen-rich gases into said reactor;
- (e) hydrotreating said first stream comprising resid and said second stream comprising recycled resins with said hydrogen-rich gases in the presence of said hydrotreating catalyst under hydrotreating conditions to produce hydrotreated oil;
- (f) feeding a high temperature component in an output stream produced in step (e) to a high temperature flash drum;
- (g) solvent separating a nonfractionated liquid output stream from said flash drum of step (f), said separation of step (g) producing asphaltenes, resins, and oil;
- (h) fractionating medium and low temperature components produced in step (e) in at least one fractionator to yield distillable liquid products; and
- (i) recycling said second stream comprising said recycled deasphalted resins to said reactor.
- 29. The process of claim 28 and the added steps of:
- (j) substantially separating said resid bottoms of step (h) into one stream comprising asphaltenes and said second stream comprising said substantially deasphalted resins.
- 30. A process for hydrotreating a resid feedstock comprising the steps of:
- hydrotreating the resid feedstock in an ebullated bed reactor in the presence of a hydrocracking catalyst and hydrogen;
- flashing effluent from the reactor to separate the reactor effluent into a volatile fraction and a hydrotreated heavy oil liquid fraction;
- transferring the heavy oil liquid fraction to a solvent extraction unit without further distillative fractionation of the heavy oil fraction; and
- deasphalting the heavy oil fraction in a solvent extraction unit.
- 31. The process of claim 30 wherein the deasphalted heavy oil fraction is solvent extracted to produce a resin fraction and an oil fraction and wherein the resin fraction si recycled to the ebullated bed reactor.
- 32. The process of claim 31 wherein the oil fraction is transferred to a catalytic feed hydrotreating unit, a distillation unit or a fluidized catalytic cracking unit.
Parent Case Info
This is a continuation-in-part of Ser. Nos. 07/616,208 now U.S. Pat. No. 5,124,026;; 07/616,218 now U.S. Pat. No. 5,124,027; and 07/616,219 now U.S. Pat. No. 5,124,025 each of which was filed Nov. 20, 1990 each of which, in turn, was a continuation-in-part of Ser. No. 07/381,372 filed Jul. 18, 1989, now U.S. Pat. No. 5,013,427 issued May 7, 1991.
US Referenced Citations (4)
Related Publications (2)
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Number |
Date |
Country |
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616281 |
Nov 1990 |
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616219 |
Nov 1990 |
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Continuation in Parts (2)
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Number |
Date |
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Parent |
616208 |
Nov 1990 |
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Parent |
381372 |
Jul 1989 |
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