Apparatuses and methods for controlling heat for rapid thermal processing of carbonaceous material
View Patent ↗Embodiments of apparatuses and methods for controlling heat for rapid thermal processing of carbonaceous material are provided herein. The apparatus comprises a reheater for containing a fluidized bubbling bed comprising an oxygen-containing gas, inorganic heat carrier particles, and char and for burning the char into ash to form heated inorganic particles. An inorganic particle cooler is in fluid communication with the reheater to receive a first portion of the heated inorganic particles. The inorganic particle cooler is configured to receive a cooling medium for indirect heat exchange with the first portion of the heated inorganic particles to form first partially-cooled heated inorganic particles that are fluidly communicated to the reheater and combined with a second portion of the heated inorganic particles to form second partially-cooled heated inorganic particles. A reactor is in fluid communication with the reheater to receive the second partially-cooled heated inorganic particles.
1. A method for controlling heat for rapid thermal processing of carbonaceous material, the method comprising the steps of:
combining an oxygen-containing gas, inorganic heat carrier particles, and char at combustion conditions effective to burn the char into ash and heat the inorganic heat carrier particles to form heated inorganic particles;
indirectly exchanging heat from a first portion of the heated inorganic particles to a cooling medium to form first partially-cooled heated inorganic particles and a heated cooling medium; and
combining the first partially-cooled heated inorganic particles with a second portion of the heated inorganic particles to form second partially-cooled heated inorganic particles.
2. The method according to claim 1 , wherein the step of combining the oxygen-containing gas, the inorganic heat carrier particles, and the char comprises forming the heated inorganic particles having a temperature of from about 600 to about 780° C.
3. The method according to claim 1 , wherein the step of indirectly exchanging heat comprises forming the first partially-cooled heated inorganic particles having a temperature of from about 500 to about 680° C.
4. The method according to claim 1 , wherein the step of combining the first partially-cooled heated inorganic particles with the second portion of the heated inorganic particles comprises forming the second partially-cooled heated inorganic particles having a temperature of from about 600 to about 780° C.
5. The method according to claim 1 , wherein the step of indirectly exchanging heat comprises indirectly exchanging heat from the first portion of the heated inorganic particles to the cooling medium that has a temperature of about 40° C. or less.
6. The method according to claim 1 , wherein the heated cooling medium has a temperature of about 125° C. or greater.
7. The method according to claim 1 , wherein the heated cooling medium comprises heated air.
8. The method according to claim 7 , further comprising the step of:
removing water from the carbonaceous material with the heated air to form a water-depleted carbonaceous material.
9. The method according to claim 8 , further comprising the step of:
contacting the water-depleted carbonaceous material with the second partially-cooled heated inorganic particles to rapidly pyrolyze the water-depleted carbonaceous material.
10. The method according to claim 8 , wherein the step of removing water comprises forming the water-depleted carbonaceous material having a water content of about 6 wt. % or less.
11. An apparatus for controlling heat for rapid thermal processing of carbonaceous material, the apparatus comprising:
a reheater configured to contain a fluidized bubbling bed that comprises an oxygen-containing gas, inorganic heat carrier particles, and char and to operate at combustion conditions effective to burn the char into ash and heat the inorganic heat carrier particles to form heated inorganic particles;
an inorganic particle cooler in fluid communication with the reheater to receive a first portion of the heated inorganic particles and configured to receive a cooling medium for indirect heat exchange with the first portion of the heated inorganic particles to form first partially-cooled heated inorganic particles and a heated cooling medium, wherein the reheater and the inorganic particle cooler are cooperatively configured to combine the first partially-cooled heated inorganic particles with a second portion of the heated inorganic particles in the reheater to form second partially-cooled heated inorganic particles; and
a reactor in fluid communication with the reheater to receive the second partially-cooled heated inorganic particles.
12. The apparatus according to claim 1 , wherein the cooling medium comprises air and the inorganic particle cooler is configured to indirectly exchange heat from the first portion of the heated inorganic particles to the cooling medium to form heated air, and wherein the apparatus further comprises a dryer that is in fluid communication with the inorganic particle cooler to receive the heated air, and wherein the dryer is configured to receive the carbonaceous material and to remove water from the carbonaceous material with the heated air to form a water-depleted carbonaceous material, and wherein the reactor is configured to receive the water-depleted carbonaceous material and to rapidly pyrolyze the water-depleted carbonaceous material with the second partially-cooled heated inorganic particles.
13. An apparatus for controlling heat for rapid thermal processing of carbonaceous material, the apparatus comprising:
a reactor;
a reheater in fluid communication with the reactor to receive inorganic heat carrier particles and char, wherein the reheater is configured to form a fluidized bubbling bed that comprises an oxygen-containing gas, the inorganic heat carrier particles, and the char and to operate at combustion conditions effective to burn the char into ash and heat the inorganic heat carrier particles to form heated inorganic particles; and
an inorganic particle cooler in fluid communication with the reheater and comprising a shell portion and a tube portion that is disposed in the shell portion, wherein the inorganic particle cooler is configured such that the tube portion receives a portion of the heated inorganic particles and the shell portion receives a cooling medium for indirect heat exchange with the portion of the heated inorganic particles to form:
(i) partially-cooled heated inorganic particles that are fluidly communicated to the reheater; and
(ii) a heated cooling medium.
14. The apparatus according to claim 13 , wherein the tube portion comprises a plurality of tubes each having an outer surface and at least one cooling fin that is disposed along the outer surface.
15. The apparatus according to claim 13 , wherein the tube portion comprises a plurality of juxtaposed tubes that are spaced apart and longitudinally disposed substantially parallel to a vertical axis.
16. The apparatus according to claim 13 , wherein the inorganic particle cooler comprises:
an exchanger vessel comprising the shell and tube portions;
a lift riser disposed downstream from the exchanger vessel; and
a sand-air distributor disposed within the reheater downstream from the lift riser, and wherein the lift riser is configured to receive and fluidly communicate the partially-cooled heated inorganic particles to the sand-air distributor and the sand-air distributor is configured to distribute the partially-cooled heated inorganic particles in the reheater.
17. The apparatus according to claim 16 , wherein the lift riser has a lower portion extending to an upper portion, the lower portion is configured to receive the partially-cooled heated inorganic particles and the upper portion is fluidly coupled to the sand-air distributor, and wherein the lift riser comprises an air nozzle that is positioned in the lower portion and that is configured to direct the partially-cooled heated inorganic particles through the lift riser from the lower portion to the upper portion for introduction to the sand-air distributor.
18. The apparatus according to claim 16 , wherein the reheater has a lower section for containing the fluidized bubbling bed and comprises a gas distributor that is disposed in the lower section and that is configured to fluidly communicate the oxygen-containing gas to the fluidized bubbling bed, and wherein the sand-air distributor is disposed above the gas distributor.
19. The apparatus according to claim 18 , wherein the inorganic particle cooler is fluidly coupled to the lower section of the reheater to receive the portion of the heated inorganic particles.
20. The apparatus according to claim 16 , wherein the inorganic particle cooler further comprises at least one bubble breaking grating that is disposed upstream from the tube portion.