Process for conversion of biomass in multi-zone reactor
View Patent ↗A two-stage reactor is disclosed for the conversion of solid particulate biomass material. The reactor is designed to maximize conversion of the solid biomass material, while limiting excess cracking of primary reaction products. The two-stage reactor comprises a first stage rector, in which solid biomass material is thermally pyrolyzed to primary reaction products. The primary reaction products are catalytically converted in a second stage reactor.
1. A two-stage process for the conversion of solid particulate biomass material, the process comprising:
(i) a first stage comprising the step of subjecting the solid particulate biomass material to a pyrolysis reaction in a first zone of a reactor to produce primary reaction products;
(ii) a second stage comprising the step of subjecting at least part of the primary reaction products to a catalytic conversion reaction in a second zone of the reactor, in the presence of a catalyst, to produce secondary reaction products, wherein the first and second zones of the reactor are in fluid communication and further wherein the second zone of the reactor is positioned above the first zone of the reactor; and
(iii) wherein the first and second zones each have an internal diameter and wherein the internal diameter of the second zone is less than the internal diameter of the first zone.
2. The two-stage process according to claim 1 further comprising removing solid particles from the secondary reaction products, wherein the solid particles comprise deactivated catalyst particles.
3. The two-stage process according to claim 2 further comprising regenerating at least part of the deactivated catalyst particles, forming regenerated catalyst particles.
4. The two-stage process according to claim 3 further comprising stripping volatile materials from the deactivated catalyst particles prior to regenerating.
5. The two-stage process according to claim 1 further comprising recycling catalyst particles back to the first zone, or the second zone, or both the first and second zones of the reactor.
6. The two-stage process according to claim 3 further comprising recycling at least a portion of the regenerated catalyst particles back to the reactor.
7. The two-stage process according to claim 6 wherein at least a portion of the regenerated catalyst particles are recycled back to the second zone of the reactor.
8. The two-stage process according to claim 1 wherein the reactor temperature in the second zone is higher than the reactor temperature in the first zone.
9. The two-stage process according to claim 8 wherein the reactor temperature in the first zone is in the range of from about 350° C. to about 600° C.
10. The two-stage process according to claim 8 wherein the reactor temperature in the first zone is in the range of from 400° C. to 550° C.
11. A process for converting solid particulate biomass material in a single circulating fluidized reactor, the process comprising:
(i) pyrolyzing at least a portion of the solid particulate biomass material to form primary reaction products within a lower zone of the reactor, the lower zone having a frustrum geometry; and
(ii) catalytically converting at least a portion of the primary reaction products into secondary reaction products in the presence of a catalyst within an upper cylindrical zone of the reactor
wherein the lower zone of the reactor is in fluid communication with the upper zone of the reactor and further wherein each of the first zone and second zone have an internal diameter, the diameter of the lower zone being greater than the diameter of the upper zone.
12. The process according to claim 11 further comprising removing solid particles from the secondary reaction products, wherein the solid particles comprise deactivated catalyst particles.
13. The process according to claim 11 further comprising recycling catalyst particles back to the lower zone, or the upper zone, or both the lower and upper zones of the reactor.
14. The process according to claim 12 further comprising stripping volatile materials from the deactivated catalyst particles.
15. The process according to claim 14 further comprising regenerating at least part of the deactivated catalyst particles from the stripper, forming regenerated catalyst particles.
16. The process according to claim 15 further comprising recycling regenerated catalyst particles back to the reactor.
17. The process according to claim 16 wherein at least a portion of the regenerated catalyst particles are recycled back to the upper zone of the reactor.
18. The process according to claim 11 wherein the reactor temperature in the upper zone is higher than the reactor temperature in the lower zone.
19. A two-stage process for the conversion of solid particulate biomass material in a single reactor, the process comprising:
(i) introducing a lift gas into a first zone of the reactor and pyrolyzing the solid particulate biomass material in the first zone to produce primary reaction products;
(ii) conveying the primary reaction products within the lift gas to a second zone of the reactor and converting in the presence of a catalyst at least part of the primary reaction products to secondary reaction products wherein the velocity of the lift gas is accelerated upon entering the second zone of the reactor;
(iii) wherein the first and second zones of the reactor are in fluid communication and further wherein the second zone of the reactor is positioned above the first zone of the reactor; and wherein the first and second zones each have an internal diameter and wherein the internal diameter of the second zone is less than the internal diameter of the first zone.
20. The two-stage process of claim 19 , wherein the biomass is pyrolyzed in the first zone in a bed ebulliated or fluidized with the lift gas.
21. The two-stage process of claim 19 , wherein solid particulate biomass material is fluidized with the lift gas prior to pyrolysis.
22. The two-stage process of claim 19 , wherein inert particulate material, deactivated particulate catalyst material or a combination thereof is in the first zone of the reactor and is conveyed to the second zone of the reactor in the lift gas.
23. The two-stage process of claim 19 , wherein a fluidizable particulate solid heat carrier material comprising deactivated particulate catalyst is in the first zone of the reactor.
24. The two-stage process of claim 23 , wherein the mean particle diameter of the fluidizable particulate solid heat carrier material is in the range of from about 50 μm to about 600 μm.
25. The two-stage process of claim 19 , wherein a particulate solid heat material is in the first zone and further wherein the temperature in the first zone is maintained with the particulate solid heat material.
26. The two-stage process of claim 19 , further comprising quenching the temperature in the second zone with a gas, solid particulate material or steam having temperature lower than the primary reaction products conveyed into the second zone.