Direct sorbent preparation/feed apparatus and method for circulating fluidized bed boiler systems

Abstract

A sorbent conditioning and feed apparatus for a circulating fluidized bed combustion system includes a dryer apparatus configured to dry unprocessed sorbent material transported thereto from a raw storage container; a sorbent crushing device configured to reduce the particle size of dried sorbent material discharged from the dryer apparatus; and a circulating fluidized bed (CFB) boiler configured to receive processed sorbent material conveyed from the sorbent crushing device; wherein the dryer apparatus utilizes an untempered hot air source diverted directly from a primary air stream input to the circulating fluidized bed boiler.

1 . A sorbent conditioning and feed apparatus for a circulating fluidized bed (CFB) combustion system, comprising:
 a dryer apparatus configured to dry unprocessed sorbent material transported thereto from a raw storage container;   a sorbent crushing device configured to reduce the particle size of dried sorbent material discharged from the dryer apparatus; and   a circulating fluidized bed boiler configured to receive processed sorbent material conveyed from the sorbent crushing device;   wherein the dryer apparatus utilizes an untempered hot air source diverted directly from a primary air stream input to the circulating fluidized bed boiler.   
   
   
       2 . The apparatus of  claim 1 , wherein the temperature of the untempered hot air source is at least about 400° F. 
   
   
       3 . The apparatus of  claim 1 , wherein the dryer apparatus is further configured to remove sorbent fines from the unprocessed sorbent material prior to input to the sorbent crushing device. 
   
   
       4 . The apparatus of  claim 3 , wherein the sorbent fines removed by the dryer apparatus are diverted directly to the CFB boiler. 
   
   
       5 . The apparatus of  claim 3 , wherein the sorbent fines removed by the dryer apparatus are diverted to the CFB boiler using a portion of boiler system secondary air discharged from the dryer apparatus. 
   
   
       6 . The apparatus of  claim 1 , wherein the sorbent crushing device comprises a roll crusher. 
   
   
       7 . A direct limestone conditioning and feed apparatus for a circulating fluidized bed (CFB) combustion system, comprising:
 a dryer apparatus configured to dry unprocessed limestone material transported thereto from a raw storage container;   a roll crushing device configured to reduce the particle size of dried limestone material discharged from the dryer apparatus; and   a circulating fluidized bed boiler configured to receive processed limestone material conveyed from the roll crushing device;   wherein the dryer apparatus utilizes an untempered hot air source diverted directly from a primary air stream input to the circulating fluidized bed boiler.   
   
   
       8 . The apparatus of  claim 7 , wherein the temperature of the untempered hot air source is at least about 400° F. 
   
   
       9 . The apparatus of  claim 7 , wherein the dryer apparatus is further configured to remove limestone fines from the unprocessed limestone material prior to input to the roll crushing device. 
   
   
       10 . The apparatus of  claim 9 , wherein the limestone fines removed by the dryer apparatus are diverted directly to the CFB boiler. 
   
   
       11 . The apparatus of  claim 9 , wherein the limestone fines removed by the dryer apparatus are diverted to the CFB boiler using a portion of boiler system secondary air discharged from the dryer apparatus. 
   
   
       12 . The apparatus of  claim 7 , wherein the dryer apparatus comprises a fluidized bed dryer. 
   
   
       13 . A method of conditioning and feeding sorbent material for a circulating fluidized bed combustion system, the method comprising:
 transporting raw, unprocessed sorbent material from a raw storage container to a dryer apparatus;   diverting untempered hot air directly from a primary air stream input to the circulating fluidized bed boiler, the untempered hot air used to dry the raw sorbent material;   directing dried raw sorbent material from the dryer apparatus to a crushing device configured to reduce the particle size of the dried raw sorbent material discharged from the dryer apparatus; and   conveying processed sorbent material from the crushing device to the CFB boiler.   
   
   
       14 . The method of  claim 13 , wherein the temperature of the untempered hot air source is at least about 400° F. 
   
   
       15 . The method of  claim 13 , further comprising using the dryer apparatus to remove sorbent fines from the raw sorbent material prior to directing the dried raw sorbent material from the dryer apparatus to a crushing device. 
   
   
       16 . The method of  claim 15 , wherein the sorbent fines removed by the dryer apparatus are diverted directly to the CFB boiler. 
   
   
       17 . The method of  claim 15 , wherein the sorbent fines removed by the dryer apparatus are diverted to the CFB boiler using a portion of boiler system secondary air discharged from the dryer apparatus. 
   
   
       18 . The method of  claim 13 , wherein the dryer apparatus comprises a fluidized bed dryer. 
   
   
       19 . The method of  claim 13 , wherein the sorbent crushing device comprises a roll crusher. 
   
   
       20 . The method of  claim 13 , wherein the sorbent comprises limestone.