Gasification apparatus and method

Abstract

A gasification system is disclosed having a combustor, a scrubber, a finisher, and optionally a recycler. A carbonaceous fuel is partially combusted in the combustor to generate a combustible gas. An improved ash support and removal system reduces clogging and other problems in the combustor. The combustible gas passes through the scrubber to remove matter such as tar and oil and to undergo preliminary catalytic chemical reactions. The scrubbed gas passes through a hybrid blower to the finisher. Final catalytic chemical reactions occur in the finisher, and wood chips or other filters may also be used in the finisher to provide a relatively clean, dry, combustible gas. Wastewater and other waste products from the scrubber and finisher are captured in the recycler and returned to the combustor.

1 . A method, comprising: 
 (1) at least partially combusting a carbonaceous fuel to produce a combustible gas;    (2) passing said combustible gas through one or more first filters to produce a scrubbed gas;    (3) passing said scrubbed gas through one or more second filters to produce a finished gas; and    (4) after step (3), combusting said scrubbed and finished gas.    
     
     
         2 . The method of  claim 1 , wherein step (1) comprises: 
 at least partially combusting said carbonaceous fuel to produce said combustible gas, said carbonaceous fuel comprising chicken litter.    
     
     
         3 . The method of  claim 1 , wherein step (1) comprises: 
 at least partially combusting said carbonaceous fuel to produce said combustible gas, said carbonaceous fuel comprising wood pulp sludge.    
     
     
         4 . The method of  claim 1 , wherein: 
 step (1) comprises at least partially combusting said carbonaceous fuel in a combustor to produce said combustible gas; and    step (2) comprises passing said combustible gas through said one or more first filters in a scrubber to produce said scrubbed gas; and further comprising    passing wastewater from said scrubber to said combustor.    
     
     
         5 . The method of  claim 1 , wherein: 
 step (1) comprises at least partially combusting said carbonaceous fuel in a combustor to produce said combustible gas; and    step (3) comprises passing said scrubbed gas through said one or more second filters in a finisher; and further comprising    passing wastewater from said finisher to said combustor.    
     
     
         6 . The method of  claim 1 , wherein: 
 step (3) comprises passing said scrubbed gas through said one or more second filters in a finisher; and further comprising:    passing wastewater from said finisher to said combustor.    
     
     
         7 . The method of  claim 1 , wherein: 
 step (1) comprises at least partially combusting said carbonaceous fuel in a combustor to produce said combustible gas;    step (2) comprises passing said combustible gas through said one or more first filters in a scrubber to produce said scrubbed gas; and    step (3) comprises passing said scrubbed gas through said one or more second filters in a finisher; and further comprising:    passing wastewater from said scrubber to a recycler;    passing wastewater from said finisher to said recycler; and    passing said wastewater from said scrubber and said wastewater from said finisher from said recycler to said combustor.    
     
     
         8 . The method of  claim 1 , wherein the one or more first filters comprise one or more catalysts.  
     
     
         9 . The method of  claim 1 , wherein the one or more first filters comprise one or more liquids.  
     
     
         10 . A method, comprising: 
 (1) at least partially combusting a carbonaceous fuel in a combustor to produce a combustible gas;    (2) passing said combustible gas to a scrubber;    (3) passing said combustible gas through one or more filters within said scrubber; and    (4) passing a first portion of the one or more filters from said scrubber to said combustor.    
     
     
         11 . The method of  claim 10 , wherein step (3) comprises: 
 passing said combustible gas through said one or more filters within said scrubber, said one or more filters comprising water.    
     
     
         12 . The method of  claim 10 , wherein step (3) comprises: 
 passing said combustible gas through the one or more filters within said scrubber to remove matter from said combustible gas, said matter comprising tar and oil; and    further comprising:    passing said tar and oil from said scrubber to said combustor.    
     
     
         13 . The method of  claim 10 , further comprising: 
 passing said combustible gas from said scrubber to a finisher; and    passing a waste liquid from said finisher to said combustor.    
     
     
         14 . The method of  claim 10 , wherein step (4) comprises: 
 passing said first portion of said liquid from said scrubber to a recycler; and    passing said first portion of said liquid from said recycler to said combustor.    
     
     
         15 . The method of  claim 14 , wherein step (3) comprises: 
 passing said combustible gas through the one or more filters within said scrubber to remove matter from said combustible gas, said matter comprising tar and oil; and    further comprising:    passing said tar and oil from said scrubber to said recycler; and    passing said tar and oil from said recycler to said combustor.    
     
     
         16 . The method of  claim 15 , further comprising: 
 passing said combustible gas from said scrubber to a finisher;    passing waste liquid from said finisher to said recycler; and    passing said waste liquid from said recycler to said combustor.    
     
     
         17 . The method of  claim 10 , wherein said one or more filters comprise one or more catalysts.  
     
     
         18 . The method of  claim 10 , wherein said one or more filters comprise one or more liquids.  
     
     
         19 . A combination, comprising: 
 a combustor having an upper outer wall portion and a lower base portion;    an inner wall disposed within said combustor, an upper portion of said inner wall being connected to said combustor to form an inner chamber and an outer chamber, a lower portion of said inner wall defining a first opening within said combustor;    an ash support member disposed within said combustor below said first opening, said ash support member being affixed within said combustor so that ash may spill from said ash support member over at least approximately 80 percent of an outer periphery of said ash support member.    
     
     
         20 . The combination of  claim 19 , wherein said ash support member is affixed within said combustor so that ash may spill from said ash support member over at least approximately 90 percent of said outer periphery of said ash support member.  
     
     
         21 . The combination of  claim 19 , further comprising: 
 a first agitating member disposed within said combustor above said opening; and    a second agitating member disposed within said combustor below said opening.    
     
     
         22 . The combination of  claim 21 , further comprising a third agitating member disposed within said combustor above said opening.  
     
     
         23 . The combination of  claim 19 , further comprising: 
 a scrubber, said scrubber being operably connected to said combustor to provide a flow path from said outer chamber of said combustor to said scrubber;    a finisher, said finisher being operably connected to said scrubber; and    one or more filters disposed in said finisher.    
     
     
         24 . The combination of  claim 19 , further comprising: 
 a blower disposed downstream from said combustor and operably connected to said combustor for withdrawing a combustible gas from said combustor, said blower comprising:    an impeller housing;    an impeller disposed within said impeller housing; and    a seal between portions of said impeller housing.    
     
     
         25 . The combination of  claim 24 , wherein said blower further comprises: 
 a shaft affixed to said impeller; and    at least two sets of bearings operably connected to said shaft.