Bulk fueled gasifiers

Abstract

A gasifier includes a gasifier shell, means for introducing fuel into the shell, and means for introducing oxygenate into the shell. The gasifier also includes means for discharging gas from the shell, which can be located below the means for introducing oxygenate. The gasifier can also include means for re-circulating gas prior to gas being discharged from the shell.

1 . A gasifier comprising:
 a gasifier shell;   means for introducing fuel into said shell;   means for introducing oxygenate into said shell; and   means for discharging gas from said shell, wherein said means for discharging is located below said means for introducing oxygenate.   
   
   
       2 . The gasifier of  claim 1  wherein said means for discharging includes a torus shaped pipe located inside said shell and a gas exit pipe extending through said shell. 
   
   
       3 . The gasifier of  claim 2  further comprising means for directing gas into said torus shaped pipe. 
   
   
       4 . The gasifier of  claim 3  wherein said means for directing gas includes a torus shaped nose and a cone solid. 
   
   
       5 . The gasifier of  claim 1  further comprising means for discharging slag and/or ash from said shell. 
   
   
       6 . The gasifier of  claim 5  wherein said means for discharging slag and/or ash includes a tap hole formed in said shell and an inductive coil disposed around said tap hole. 
   
   
       7 . The gasifier of  claim 1  further comprising means for re-circulating gas prior to gas being discharged from said shell. 
   
   
       8 . The gasifier of  claim 7  wherein said means for re-circulating gas includes a blower located at or near the top of the shell and one or more down-flow tubes, said down-flow tubes directing gas into said means for introducing oxygenate. 
   
   
       9 . The gasifier of  claim 1  further comprising an agitator disposed in said shell. 
   
   
       10 . A gasifier comprising:
 a gasifier shell;   means for introducing fuel into said shell;   means for introducing oxygenate into said shell, wherein a fire zone is created in said shell adjacent to said means for introducing oxygenate;   means for discharging gas from said shell; and   means for re-circulating gas prior to gas being discharged from said shell.   
   
   
       11 . The gasifier of  claim 10  wherein said shell defines a wall and an interior, and said means for re-circulating gas includes one or more re-circulation tubes running lengthwise in said wall. 
   
   
       12 . The gasifier of  claim 11  wherein said means for re-circulating gas further includes a re-circulating blower that draws gas from said interior of said shell and into said re-circulation tubes. 
   
   
       13 . The gasifier of  claim 12  wherein said re-circulating blower is driven by a variable speed motor. 
   
   
       14 . The gasifier of  claim 11  further comprising a valve associated with each re-circulation tube, wherein said valve can be adjusted to control how much gas from said re-circulation tube is directed into said fire zone. 
   
   
       15 . The gasifier of  claim 10  wherein said means for introducing fuel includes a chute that is offset from the center of said shell. 
   
   
       16 . The gasifier of  claim 10  further comprising an agitator disposed in said shell. 
   
   
       17 . The gasifier of  claim 10  further comprising means for discharging slag and/or ash from said shell.