System and method for removing ash deposits within a boiler

Abstract

A system for removing ash deposits within a boiler is provided. The system includes a soot blower disposed within the boiler, and a gas supply line in fluid communication with the soot blower and a gas source. The soot blower is operative to inject compressed gas from the gas source into the boiler to remove the ash deposits from a surface of the boiler.

What is claimed is: 
     
         1 . A system for removing ash deposits within a boiler comprising:
 a soot blower disposed within the boiler,   a gas supply line in fluid communication with the soot blower and a gas source; and   wherein the soot blower is operative to inject compressed gas from the gas source into the boiler to remove the ash deposits from a surface of the boiler.   
     
     
         2 . The system of  claim 1 , wherein the compressed gas is carbon dioxide. 
     
     
         3 . The system of  claim 1 , wherein the gas source is the boiler. 
     
     
         4 . The system of  claim 3 , further comprising:
 a compressor disposed downstream of the boiler for compressing a flue gas stream discharged from the boiler; and   wherein the flue gas stream is the compressed gas.   
     
     
         5 . The system of  claim 3 , further comprising:
 a compressor disposed downstream of the boiler for compressing a flue gas stream discharged from the boiler;   a separator disposed downstream of the compressor that is operative to separate carbon dioxide from the flue gas stream; and   wherein the separated carbon dioxide is the compressed gas.   
     
     
         6 . The system of  claim 5 , further comprising:
 a series of compressors disposed downstream of the separator and operative to compress the separated carbon dioxide prior to being injected into the boiler by the soot blower.   
     
     
         7 . The system of  claim 6 , further comprising:
 a heat exchanger for heating the separated carbon dioxide prior to being injected into the boiler by the soot blower; and   wherein the heat exchanger heats the separated carbon dioxide via cooling the flue gas stream.   
     
     
         8 . The system of  claim 7 , wherein the heat exchanger is disposed downstream of the compressor and upstream of the separator. 
     
     
         9 . The system of  claim 1  further comprising:
 a heat recovery system that includes a particulate remover and a desulferizer, the heat recovery system operative to recover heat from a flue gas stream discharged by the boiler; and 
 wherein the compressed gas is heated by the flue gas stream between the particulate remover and the desulferizer. 
 
     
     
         10 . The system of  claim 1 , wherein the boiler is an oxy-fuel combustion boiler. 
     
     
         11 . A method for removing ash deposits within a boiler comprising:
 supplying a compressed gas from a gas source via a supply line to a soot blower disposed within the boiler;   injecting the compressed gas into the boiler via the soot blower so as to remove the ash deposits from a surface of the boiler.   
     
     
         12 . The method of  claim 11 , wherein the compressed gas is carbon dioxide. 
     
     
         13 . The method of  claim 11 , wherein the gas source is the boiler. 
     
     
         14 . The method of  claim 13  further comprising:
 compressing a flue gas stream discharged from the boiler via a compressor disposed downstream of the boiler; and 
 wherein the flue gas stream is the compressed gas. 
 
     
     
         15 . The method of  claim 13  further comprising:
 compressing a flue gas stream discharged from the boiler via a compressor disposed downstream of the boiler; 
 separating carbon dioxide from the flue gas stream via a separator disposed downstream of the compressor; and 
 wherein the separated carbon dioxide is the compressed gas. 
 
     
     
         16 . The method of  claim 15  further comprising:
 compressing, via a series of compressors disposed downstream of the separator, the separated carbon dioxide prior to injecting the separated carbon dioxide via the soot blower into the boiler. 
 
     
     
         17 . The method of  claim 16  further comprising:
 heating the separated carbon dioxide via a heat exchanger prior to injecting the separated carbon dioxide via the soot blower into the boiler; and 
 wherein the heat exchanger heats the separated carbon dioxide via cooling the flue gas stream. 
 
     
     
         18 . The method of  claim 17 , wherein the heat exchanger is disposed downstream of the compressor and upstream of the separator. 
     
     
         19 . The method of  claim 11  further comprising:
 recovering heat from a flue gas stream discharged by the boiler via a heat recovery system that includes a particulate remover and a desulferizer; and 
 heating the compressed gas via the flue gas stream between the particulate remover and the desulferizer. 
 
     
     
         20 . A system for removing ash deposits within a boiler comprising:
 a soot blower disposed within the boiler;   a gas supply line in fluid communication with the soot blower and a carbon dioxide gas storage vessel; and   wherein the soot blower is operative to inject carbon dioxide gas received from the carbon dioxide gas storage vessel into the boiler to remove the ash deposits from a surface of the boiler.