This invention is directed to a process for removing catalyst particles from a gas. The invention is particularly suited to separating particles from the gas in a vessel that has a dilute phase zone and a dense phase zone. An acoustic waveform is applied to the dilute phase zone to assist in separating small particles from the gas in the dilute phase zone.
Description
DETAILED DESCRIPTION OF THE DRAWING
FIG. 1 shows the flow of gas and fluidized solids through a vessel and subsequent separation of the solids from the gas.
Claims
1. A process for removing catalyst particles from a dilute phase zone of a vessel and recovering the catalyst particles in a dense phase zone, comprising:
flowing gas and catalyst particles into a dilute phase zone;applying an acoustic waveform to the dilute phase zone to agglomerate at least a portion of catalyst particles in the dilute phase zone;removing at least a portion of the agglomerated particles from the dilute phase zone; andrecovering at least a portion of the removed particles in a dense phase zone.
2. The process of claim 1, wherein the gas is a hydrocarbon or regeneration medium.
3. The process of claim 1, wherein the catalyst particles are molecular sieve catalyst particles.
4. The process of claim 1, wherein the catalyst particles have an ARI of not greater than 5 wt %/hr.
5. The process of claim 1, wherein the dilute phase zone has a particle density less than that of the dense phase zone.
6. The process of claim 1, wherein the catalyst particles have a particle size distribution such that not greater than about 20 wt % of the catalyst particles in the dense phase zone have an average diameter less than or equal to 20 μm.
7. The process of claim 1, wherein the catalyst particles have a particle size in which not greater than about 20 wt % of the catalyst particles in the dense phase zone have an average diameter greater than or equal to about 250 μm.
8. The process of claim 1, wherein the catalyst particles in the dense phase zone have a particle size distribution in μm of 1<d10<75; 20<d50<200; and 50<d90<400.
9. The process of claim 1, wherein the dilute phase zone has a solid volume of from about 0.01% to about 15%.
10. The process of claim 1, wherein the dilute phase zone typically has about 1% or less solid volume as that contained in the dense phase zone.
11. The process of claim 1, wherein, the dense phase zone has a solid volume content of from about 20% to about 40%.
12. The process of claim 1, wherein the dilute phase zone and dense phase zone located in a common vessel.
13. The process of claim 1, wherein the acoustic waveform is amplitude modulated, frequency modulated, or both amplitude and frequency modulated.
14. The process of claim 1, wherein the acoustic waveform is modulated in a frequency range of up to 1 GHz.
15. The process of claim 1, wherein the acoustic waveform is modulated in amplitude range of up to 200 dB referenced to 20 micro-Pascals.
16. The process of claim 1, wherein the acoustic waveform is applied as a standing waveform.
17. The process of claim 1, wherein the agglomerated particles are removed using a disengaging unit.
18. A process for separating solid particles from a gas composition in a vessel having a dilute phase zone and a dense phase zone, wherein the dilute phase zone has a particle density less than that of the dense phase zone, the process comprising:
flowing a gas composition containing solid particles through the dilute phase zone of the vessel;applying an acoustic waveform to the dilute phase zone to agglomerate at least a portion of the particles in the gas composition;flowing at least a portion of the gas and agglomerated particles through one or more cyclones to separate at least a portion of the agglomerated particles from the gas; andsending at least a portion of the separated particles to the dense phase zone of the vessel.
19. The process of claim 18, wherein the gas is a hydrocarbon or regeneration medium.
20. The process of claim 18, wherein the catalyst particles are molecular sieve catalyst particles.
21. The process of claim 18, wherein the catalyst particles have an ARI of not greater than 5 wt %/hr.
22. The process of claim 18, wherein the dilute phase zone has a particle density less than that of the dense phase zone.
23. The process of claim 18, wherein the catalyst particles have a particle size distribution such that not greater than about 20 wt % of the catalyst particles in the dense phase zone have an average diameter less than or equal to 20 μm.
24. The process of claim 18, wherein the catalyst particles have a particle size in which not greater than about 20 wt % of the catalyst particles in the dense phase zone have an average diameter greater than or equal to about 250 μm.
25. The process of claim 18, wherein the catalyst particles in the dense phase zone have a particle size distribution in μm of 1<d10<75; 20<d50<200; and 50<d90<400.
26. The process of claim 18, wherein the dilute phase zone has a solid volume of from about 0.01% to about 15%.
27. The process of claim 18, wherein the dilute phase zone typically has about 1% or less solid volume as that contained in the dense phase zone.
28. The process of claim 18, wherein, the dense phase zone has a solid volume content of from about 20% to about 40%.
29. The process of claim 18, wherein the dilute phase zone and dense phase zone located in a common vessel.
30. The process of claim 18, wherein the acoustic waveform is amplitude modulated, frequency modulated, or both amplitude and frequency modulated.
31. The process of claim 18, wherein the acoustic waveform is modulated in a frequency range of up to 1 GHz.
32. The process of claim 18, wherein the acoustic waveform is modulated in amplitude range of up to 200 dB referenced to 20 micro-Pascals.
33. The process of claim 18, wherein the acoustic waveform is applied as a standing waveform.
34. The process of claim 18, wherein the agglomerated particles are removed using a disengaging unit.
35. A process for separating catalyst particles from hydrocarbon, comprising:
flowing a hydrocarbon feed gas through a fluidized catalyst bed to convert the feed gas to hydrocarbon product;flowing the hydrocarbon product through a dilute phase zone having a catalyst density less than that of the fluidized catalyst bed;contacting catalyst particles in the dilute phase zone with an acoustic waveform to agglomerate at least a portion of the catalyst particles; andflowing at least a portion of the agglomerated catalyst particles and hydrocarbon product to one or more cyclones to separate at least a portion of the agglomerated particles from the gas.
36. The process of claim 35, wherein the gas is a hydrocarbon or regeneration medium.
37. The process of claim 35, wherein the catalyst particles are molecular sieve catalyst particles.
38. The process of claim 35, wherein the catalyst particles have an ARI of not greater than 5 wt %/hr.
39. The process of claim 35, wherein the dilute phase zone has a particle density less than that of the dense phase zone.
40. The process of claim 35, wherein the catalyst particles have a particle size distribution such that not greater than about 20 wt % of the catalyst particles in the dense phase zone have an average diameter less than or equal to 20 μm.
41. The process of claim 35, wherein the catalyst particles have a particle size in which not greater than about 20 wt % of the catalyst particles in the dense phase zone have an average diameter greater than or equal to about 250 μm.
42. The process of claim 35, wherein the catalyst particles in the dense phase zone have a particle size distribution in μm of 1<d10<75; 20<d50<200; and 50<d90<400.
43. The process of claim 35, wherein the dilute phase zone has a solid volume of from about 0.01% to about 15%.
44. The process of claim 35, wherein the dilute phase zone typically has about 1% or less solid volume as that contained in the dense phase zone.
45. The process of claim 35, wherein, the dense phase zone has a solid volume content of from about 20% to about 40%.
46. The process of claim 35, wherein the dilute phase zone and dense phase zone located in a common vessel.
47. The process of claim 35, wherein the acoustic waveform is amplitude modulated, frequency modulated, or both amplitude and frequency modulated.
48. The process of claim 35, wherein the acoustic waveform is modulated in a frequency range of up to 1 GHz.
49. The process of claim 35, wherein the acoustic waveform is modulated in amplitude range of up to 200 dB referenced to 20 micro-Pascals.
50. The process of claim 35, wherein the acoustic waveform is applied as a standing waveform.
51. The process of claim 35, wherein the agglomerated particles are removed using a disengaging unit.
Patent Application
20070175326
