Desulfurization and Sulfone Removal Using A Coker

• US 20120055845A1
• Filed: 09/07/2010
• Published: 03/08/2012
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Bourane, Abdennour, Koseoglu, Omer Refa, Kressmann, Stephane Cyrille
• Granted Patent: US 9,574,143 B2
• Time in Patent Office: Days
• US Class Current: 208/90
• CPC Class Codes: C10B 55/00 Coking mineral oils, bitumen, tar, and the like or mixtures thereof with solid carbonaceous material cracking oils C10G
• CPC Class Codes: C10B 57/04 using charges of special composition
• CPC Class Codes: C10G 21/16 Oxygen-containing compounds
• CPC Class Codes: C10G 21/20 Nitrogen-containing compounds
• CPC Class Codes: C10G 21/22 Compounds containing sulfur, selenium, or tellurium
• CPC Class Codes: C10G 21/28 Recovery of used solvent
• CPC Class Codes: C10G 2300/202 Heteroatoms content, i.e. S, N, O, P
• CPC Class Codes: C10G 2300/301 Boiling range
• CPC Class Codes: C10G 2300/44 Solvents
• CPC Class Codes: C10G 27/04 with oxygen or compounds generating oxygen
• CPC Class Codes: C10G 27/12 with oxygen-generating compounds, e.g. per-compounds, chromic acid, chromates plumbites or plumbates C10G19/06
• CPC Class Codes: C10G 53/04 including at least one extraction step
• CPC Class Codes: C10G 53/14 including at least one oxidation step

Abstract

A method and apparatus for upgrading a hydrocarbon feedstock is provided. The method includes the steps of (a) supplying a hydrocarbon feedstock to an oxidation reactor, wherein the hydrocarbon feedstock is oxidized in the presence of a catalyst under conditions sufficient to selectively oxidize sulfur compounds present in the hydrocarbon feedstock; (c) separating the hydrocarbons and the oxidized sulfur compounds by solvent extraction; (d) collecting a residue stream that includes the oxidized sulfur compounds; and (e) supplying the residue stream to a coker to produce coker gases and solid coke.

Claims

1. A method of upgrading a hydrocarbon feedstock, the method comprising the steps of:

supplying the hydrocarbon feedstock to an oxidation reactor, the hydrocarbon feedstock comprising sulfur containing compounds;

contacting the hydrocarbon feedstock with an oxidant in the presence of a catalyst in the oxidation reactor under conditions sufficient to selectively oxidize sulfur compounds present in the hydrocarbon feedstock to produce a hydrocarbon stream that comprises hydrocarbons and oxidized sulfur containing compounds;

supplying the hydrocarbon stream to an extraction vessel and separating the hydrocarbon stream into an extracted hydrocarbon stream and a mixed stream by extracting the hydrocarbon stream with a polar solvent, wherein the mixed stream comprising the polar solvent and the oxidized sulfur containing compounds and wherein the extracted hydrocarbon stream has a lower concentration of the sulfur containing compounds than the hydrocarbon feedstock;

separating the mixed stream into a first recovered polar solvent stream and a first residue stream; and

supplying the first residue stream to a coker to produce coker vapors and solid coke.

2. The method of claim 1, wherein the oxidant is selected from the group consisting of air, oxygen, oxides of nitrogen, peroxides, hydroperoxides, organic peracids, and combinations thereof.

3. The method of claim 1, wherein the oxidation reactor catalyst is a metal oxide having the formula M_xO_y, wherein M is an element selected from Groups IVB, VB, and VIB of the periodic table.

4. The method of claim 1, wherein the oxidation reactor is maintained at a temperature of between about 20 and 150°

C. and at a pressure of between about 1-10 bars.

5. The method of claim 1, wherein the ratio of the oxidant to sulfur compounds present in the hydrocarbon feedstock is between about 4:

1 and 10;

1.

6. The method of claim 1, wherein the polar solvent has a Hildebrandt value of greater than about 19.

7. The method of claim 1, wherein the polar solvent is selected from the group consisting of acetone, carbon disulfide, pyridine, dimethyl sulfoxide, n-propanol, ethanol, n-butanol, propylene glycol, ethylene glycol, dimethlyformamide, acetonitrile, methanol and combinations of the same.

8. The method of claim 1, wherein the polar solvent is acetonitrile.

9. The method of claim 1, wherein the polar solvent is methanol.

10. The method of claim 1, wherein the solvent extraction is conducted at a temperature of between about 20°

C. and 60°

C. and at a pressure of between about 1-10 bars.

11. The method of claim 1, further comprising the step of supplying the extracted hydrocarbon stream to a stripper to produce a second recovered polar solvent stream and a stripped hydrocarbon stream.

12. The method of claim 1, wherein the hydrocarbon feedstock further comprises nitrogen containing compounds, such that the step of contacting the hydrocarbon feedstock with the oxidant in the presence the catalyst oxidizes at least a portion of the nitrogen containing compounds, and wherein the residue stream supplied to the coker includes the oxidized nitrogen containing compounds.

13. The method of claim 11, further comprising the step of supplying the extracted hydrocarbon stream to an adsorption column, the adsorption column being charged with an adsorbent suitable for the removal of oxidized compounds present in the extracted hydrocarbon stream, the adsorption column producing a high purity hydrocarbon product stream and a second residue stream, the second residue stream containing a portion of the oxidized compounds.

14. The method of claim 13, further comprising supplying the second residue stream to coker.

15. The method of claim 13, wherein the adsorbent is selected from the group consisting of activated carbon, silica gel, alumina, natural clays, and combinations of the same.

16. The method of claim 13, wherein the adsorbent is a polymer coated support, wherein the support has a high surface area and is selected from the group consisting of silica gel, alumina, and activated carbon, and the polymer is selected from the group consisting of polysulfone, polyacrylonitrile, polystyrene, polyester terephthalate, polyurethane and combinations of the same.

17. A method for upgrading a hydrocarbon feedstock comprising sulfur containing compounds, the method for upgrading the hydrocarbon feedstock comprising the steps of:

supplying the hydrocarbon feedstock having a boiling point of up to about 500°

C. to reaction zone where the hydrocarbon feedstock is contacted with an oxidant in the presence of a catalyst to oxidize at least a portion of the sulfur containing compounds in the hydrocarbon feedstock and produce an intermediate product stream comprising hydrocarbons and oxidized sulfur containing compounds;

supplying the intermediate product stream comprising hydrocarbons and oxidized sulfur containing compounds to an extraction vessel wherein the intermediate product stream is contacted with a polar solvent, wherein said polar solvent selectively extracts oxidized sulfur containing compounds from the intermediate product stream, to produce a first hydrocarbon product stream comprising hydrocarbons and having a lower concentration of sulfur containing compounds than the hydrocarbon feedstock and a mixed stream comprising the polar solvent and the extracted oxidized sulfur containing compounds;

separating the mixed stream by distillation to produce a recovered solvent stream comprising a major portion of the polar solvent, and a residue stream comprising the oxidized sulfur containing compounds;

supplying the residue stream to a coker to produce a recovered hydrocarbon product stream comprising condensed coker vapors and gas oil and solid coke, wherein the coker includes a coker furnace and a coker drum, and wherein the coker furnace is operated at a temperature of at least about 400°

C. and the coker drum is operated at a temperature of at least about 425°

C. and a pressure in the range of between about 1 and 50 kg/cm²; and

supplying at least a portion of the recovered solvent stream to the extraction vessel wherein at least a portion of the recovered solvent stream is combined with the polar solvent.

18. The method of claim 17 wherein the step of oxidizing at least a portion of the sulfur containing compounds in the hydrocarbon feedstock comprises contacting the hydrocarbon feedstock with the oxidant and catalyst in the oxidation reaction, wherein the oxidation reactor is maintained at a temperature of between about 20°

C. and 150°

C. and a pressure of between about 1 and 20 bars for a contact time of between about 5 and 60 minutes.

19. The method of claim 18 wherein the ratio of catalyst to oil is between about 0.1% and 10% by weight.

20. The method of claim 17 wherein the polar solvent has a Hildebrandt solubility value of greater than about 19.

21. The method of claim 18 wherein extraction vessel is maintained at a temperature of between about 20°

C. and 60°

C.