Processes for controlling the partial regeneration of spent catalyst from an MTO reaction

Patent metadata

Field	Value
Publication number	US-10589264-B2
Application number	US-201816100566-A
Country	US
Kind code	B2
Filing date	Aug 10, 2018
Priority date	Aug 10, 2018
Publication date	Mar 17, 2020
Grant date	Mar 17, 2020

Abstract

A method of controlling the regeneration of spent catalyst from an oxygenate-to-olefin reaction zone in order to provide a partially regenerated catalyst. The partially regenerated catalyst has between 1 to 4, or 1 to 3, or, 2 to 3 wt % coke. The regeneration is controlled by adjusting a ratio of air to recycled flue gas in the combustion gas passed to the regeneration zone. CO in the flue gas is removed in a CO oxidation zone which receives oxygen to oxidize CO to CO2.

First claim

What is claimed is:

1. A process for controlling catalyst regeneration in a catalyst regeneration zone, the process comprising:
introducing an oxygen containing gas into a catalyst regeneration zone;
partially regenerating a stream of spent catalyst from an MTO reaction zone, the spent catalyst including coke;
separating regenerated catalyst from a flue gas, the regenerated catalyst having a reduced amount of coke and the flue gas comprising carbon monoxide and carbon dioxide;
recycling a portion of the flue gas to the catalyst regeneration zone with the oxygen containing gas; and,
maintaining a ratio of carbon dioxide to carbon monoxide in the flue gas to be at least 0.5.

2. The process of claim 1 , wherein the ratio of carbon dioxide to carbon monoxide is maintained by adjusting an oxygen content of the oxygen containing gas introduced into the catalyst regeneration zone.

3. The process of claim 2 , wherein the oxygen content is adjusted by controlling a ratio of air to flue gas the in oxygen containing gas.

4. The process of claim 1 , wherein the ratio of carbon dioxide to carbon monoxide in the flue gas is maintained to be greater than 2.

5. The process of claim 1 , wherein the flue gas further comprises oxygen, and wherein the process further comprises:
maintaining an amount of oxygen in the flue gas to be less than 2%, by volume.

6. The process of claim 1 , wherein the regenerated catalyst comprises between 1 to 4%, by weight, coke.

7. A process for controlling catalyst regeneration in a catalyst regeneration zone, the process comprising:
introducing an oxygen containing gas into a catalyst regeneration zone;
partially regenerating a stream of spent catalyst from an MTO reaction zone, the spent catalyst including coke;
separating regenerated catalyst from a flue gas, the regenerated catalyst having a reduced amount of coke and the flue gas comprising oxygen;
recycling a portion of the flue gas to the catalyst regeneration zone with the oxygen containing gas; and,
maintaining an amount of oxygen in the flue gas to be less than 2%, by volume.

8. The process of claim 7 , wherein the amount of oxygen in the flue gas is maintained by adjusting an oxygen content of the oxygen containing gas introduced into the catalyst regeneration zone.

9. The process of claim 8 , wherein the oxygen content is adjusted by controlling a ratio of air to flue gas in the oxygen containing gas.

10. The process of claim 7 , wherein the regenerated catalyst comprises between 1 to 4%, by weight, coke.

11. The process of claim 10 , wherein the flue gas further comprises carbon dioxide and carbon monoxide,
and wherein the process further comprises:
maintaining a ratio of carbon dioxide to carbon monoxide in the flue gas to be at least 0.5.

12. The process of claim 11 , wherein the ratio of carbon dioxide to carbon monoxide in the flue gas is maintained to be greater than 2.

13. A process for partially regenerating catalyst from an MTO reaction zone, the process comprising:
passing a stream of oxygen containing gas into a catalyst regeneration zone;
passing a stream of spent catalyst from an MTO reaction zone to the catalyst regeneration zone, the spent catalyst including coke;
combusting coke off of the spent catalyst to provide a partially regenerated catalyst comprising between 1 to 4%, by weight, coke;
recycling a portion of a flue gas stream to the catalyst regeneration zone as the oxygen containing gas;
controlling a ratio of air to flue gas in the oxygen containing gas in order to achieve the partially regenerated catalyst by maintaining at least one of the following parameters:
an amount of oxygen in the flue gas to be less than 2%, by volume;
a ratio of carbon dioxide to carbon monoxide in the flue gas to be at least 0.5; or, an oxygen utilization in the catalyst regeneration zone of at least 90%.

14. The process of claim 13 wherein the ratio of carbon dioxide to carbon monoxide is maintained to be greater than 2.

15. The process of claim 13 further comprising:
adjusting a processing condition associated with the MTO reaction zone; and,
adjusting the ratio of air to flue gas in the oxygen containing gas in response to the adjusted processing condition of the MTO reaction zone.

16. The process of claim 13 further comprising at least one of:
sensing at least one parameter of the process and generating a signal or data from the sensing;
generating and transmitting a signal; or
generating and transmitting data.

17. The process of claim 16 further comprising:
receiving the signal or data; and,
adjusting the ratio of air to flue gas in response to the received data or signal.

18. The process of claim 13 wherein the ratio of air to flue gas in the oxygen containing gas is controlled in order to achieve the partially regenerated catalyst by maintaining at least two of the following parameters:
an amount of oxygen in the flue gas to be less than 2%, by volume;
a ratio of carbon dioxide to carbon monoxide in the flue gas to be at least 0.5; or,
an oxygen utilization in the catalyst regeneration zone of at least 90%.

19. The process of claim 13 wherein the ratio of air to flue gas in the oxygen containing gas is controlled in order to achieve the partially regenerated catalyst by maintaining the following parameters:
an amount of oxygen in the flue gas to be less than 2%, by volume;
a ratio of carbon dioxide to carbon monoxide in the flue gas to be at least 0.5; and,
an oxygen utilization in the catalyst regeneration zone of at least 90%.

20. The process of claim 13 further comprising:
adjusting the ratio of air to flue gas in the oxygen containing gas in order to maintain a constant velocity of spent catalyst particles within a reactor of the catalyst regeneration zone.

Assignees

• Uop Llc

Inventors

• Senetar John J

Classifications

• B01J2219/00229

  of the reaction system · CPC title

• B01J2219/00182

  controlling the level of reactants in the reactor vessel · CPC title

• B01J19/0006

  Controlling or regulating processes (controlling or regulating in general G05) · CPC title

• B01J38/14 Primary

  with control of oxygen content in oxidation gas · CPC title

• B01J29/90

  Regeneration or reactivation · CPC title