Systems and methods for regenerating a spent catalyst
View Patent ↗Systems and methods for regenerating a spent catalyst are provided. The method can include mixing a spent catalyst with a carrier fluid to provide a mixture. The spent catalyst can include carbon deposited on at least a portion thereof. The carrier fluid can include an oxygen containing gas. The mixture can be introduced to or above an upper surface of a dense phase catalyst zone disposed within a regenerator. A gas can be introduced to a lower zone of the dense phase catalyst zone. At least a portion of the carbon deposited on the catalyst can be combusted to provide a flue gas, heat, and a regenerated catalyst.
1. A method for regenerating a spent catalyst, comprising:
mixing a spent catalyst with a carrier fluid to provide a mixture, wherein the spent catalyst includes carbon deposited on at least a portion thereof, and wherein the carrier fluid comprises an oxygen containing gas;
introducing the mixture to a dilute phase catalyst zone disposed within a regenerator;
distributing the mixture of the dilute phase catalyst zone onto an upper surface of a dense phase catalyst zone disposed within the regenerator;
introducing a gas to a lower zone of the dense phase catalyst zone; and
combusting at least a portion of the carbon deposited on the catalyst to provide a flue gas, heat, and a regenerated catalyst.
2. The method of claim 1 , wherein the carrier fluid comprises from about 10% to about 90% of the total amount of gas introduced to the regenerator, and wherein the carrier fluid comprises from 0.5% to about 90% of the total amount of oxygen introduced to the regenerator.
3. The method of claim 1 , wherein the carrier fluid comprises from about 20% to about 50% of the total amount of gas introduced to the regenerator, and wherein the carrier fluid comprises from about 0.5% to about 50% of the total amount of oxygen introduced to the regenerator.
4. The method of claim 3 , further comprising introducing an oxygen containing gas to the regenerator above the upper surface of the dense phase catalyst zone.
5. The method of claim 1 , wherein the flue gas comprises less than about 150 ppm nitrogen oxides.
6. The method of claim 1 , further comprising distributing the mixture above the upper surface of the dense phase catalyst zone.
7. The method of claim 1 , wherein the gas comprises an oxygen-lean gas, air, or oxygen-rich gas.
8. The method of claim 7 , wherein the ratio of the oxygen introduced with the carrier fluid to the oxygen introduced with the gas ranges from about 1:1 to about 1:3.
9. The method of claim 1 , wherein the carbon deposited on the spent catalyst ranges from about 0.7% wt to about 1.3% wt.
10. The method of claim 1 , further comprising introducing a carbon monoxide combustion promoter to the regenerator.
11. The method of claim 10 , wherein the carbon monoxide combustion promoter comprises platinum at a concentration of ranging from about 0.01 ppm to about 3 ppm.
12. A method for regenerating a spent catalyst, comprising:
mixing a spent catalyst with a carrier fluid to provide a mixture, wherein the spent catalyst includes carbon deposited on at least a portion thereof;
introducing the mixture to a dilute phase catalyst zone disposed above a dense phase catalyst zone in a regenerator;
distributing the mixture of the dilute phase catalyst zone onto an upper surface of the dense phase catalyst zone;
introducing a gas to a lower portion of the dense phase catalyst zone;
combusting at least a portion of the carbon deposited on the spent catalyst to provide a flue gas, heat, and a regenerated catalyst;
introducing at least a portion of the regenerated catalyst to a fluidized catalytic cracker; and
recovering the flue gas from the regenerator, wherein the flue gas comprises less than about 150 ppm nitrogen oxides.
13. The method of claim 12 , further comprising distributing the mixture above the upper surface of the dense phase catalyst zone.
14. The method of claim 12 , wherein the carrier fluid comprises from about 10% to about 90% of a total amount of gas introduced to the regenerator, and wherein the carrier fluid comprises from about 0% to about 90% of the total amount of oxygen introduced to the regenerator.
15. The method of claim 12 , wherein the carrier fluid comprises less than about 50% of a total amount of gas introduced to the regenerator, and wherein the carrier fluid comprises less than about 50% of the total amount of oxygen introduced to the regenerator.
16. The method of claim 12 , further comprising introducing air, an oxygen-rich gas, or a combination thereof to the dilute phase catalyst zone.
17. The method of claim 12 , further comprising introducing a carbon monoxide combustion promoter to the regenerator.
18. The method of claim 17 , wherein the concentration of the carbon monoxide combustion promoter ranges from about 0.3 ppm to about 2 ppm.
19. A method for regenerating a spent catalyst, comprising:
mixing a spent catalyst with a carrier fluid to provide a dilute phase mixture, wherein the spent catalyst includes carbon deposited on at least a portion thereof;
introducing the dilute phase mixture to a dilute phase catalyst zone disposed above a dense phase catalyst zone in a regenerator;
distributing the dilute phase mixture of the dilute phase catalyst zone onto an upper surface of the dense phase catalyst zone;
introducing a gas to the lower zone;
introducing an oxygen containing gas to the dilute phase catalyst zone; and
combusting at least a portion of the carbon deposited on the catalyst to provide a flue gas, heat, and a regenerated catalyst.
20. The method of claim 19 , wherein the carrier fluid comprises a gas containing less than about 5% vol oxygen.
21. The method of claim 19 , wherein the oxygen containing gas comprises a gas mixture containing at least 10% vol oxygen.
22. The method of claim 19 , wherein the gas comprises air, an oxygen-lean gas, or an oxygen-rich gas.
23. The method of claim 19 , wherein the carbon deposited on the spent catalyst ranges from about 0.7% wt to about 1.3% wt.
24. The method of claim 19 , further comprising introducing a carbon monoxide combustion promoter to the regenerator.
25. The method of claim 24 , wherein the concentration of the carbon monoxide combustion promoter ranges from about 0.3 ppm to about 2 ppm.
26. The method of claim 1 , wherein the total amount of gas introduced to the regenerator is from about 80% to about 115% of the stoichiometric oxygen required to oxidize all of the coke and carbon monoxide within the regenerator.
27. The method of claim 1 , wherein the flue gas comprises less than about 40 ppm nitrogen oxides.
28. The method of claim 1 , wherein the flue gas comprises less than about 0.1 mol% carbon monoxide.
29. The method of claim 1 , further comprising distributing the mixture above the upper surface of the dense phase catalyst zone.
30. The method of claim 19 , wherein the dilute phase catalyst zone has a catalyst concentration from about 50 kg/m 3 to about 160 kg/m 3 .
31. The method of claim 1 , wherein the carrier fluid comprises from about 10% to about 90% of the total amount of gas introduced to the regenerator, and wherein the carrier fluid comprises from 40 to about 90% of the total amount of oxygen introduced to the regenerator.
32. The method of claim 12 , wherein the carrier fluid comprises from about 10% to about 90% of the total amount of gas introduced to the regenerator, and wherein the carrier fluid comprises from 60% to about 90% of the total amount of oxygen introduced to the regenerator.
33. The method of claim 19 , wherein the carrier fluid comprises from 10% to about 60% of the total amount of oxygen introduced to the regenerator.
34. The method of claim 19 , wherein the dilute phase mixture comprises a spent catalyst concentration of less than 175 kg/m 3 .