Gasifier for a solid carbon fuel

Abstract

Disclosed here are example gasifiers for gasification of solid carbon fuel. An example gasifier includes a vertical vessel that includes feeding means for introducing a fuel at a top and along a first vertical axis in the vessel. The example vessel also includes a pyrolysis zone for pyrolysis of the fuel, a combustion zone for burning pyrolysis gases from the pyrolysis zone, a reduction zone for gasifying carbonized fuel from the pyrolysis zone and an outlet for collecting gases produced in the reduction zone. In addition, the example vessel includes a horizontal plate fixedly mounted between the feeding means and the pyrolysis zone for receiving and retaining the fuel introduced into the vessel. Also, the example vessel includes a movable pusher mounted between the feeding means and the horizontal plate, the movable pusher to push the fuel retained on the horizontal plate into the pyrolysis zone and positioned or positionable above the horizontal plate.

1 . A gasifier comprising a vertical vessel comprising:
 feeding means for introducing a fuel at a top and along a first vertical axis in the vessel;   a pyrolysis zone for pyrolysis of the fuel;   a combustion zone for burning pyrolysis gases from the pyrolysis zone;   a reduction zone for gasifying carbonized fuel from the pyrolysis zone;   an outlet for collecting gases produced in the reduction zone;   a horizontal plate fixedly mounted between the feeding means and the pyrolysis zone for receiving and retaining the fuel introduced into the vessel; and   a movable pusher mounted between the feeding means and the horizontal plate, the movable pusher to push the fuel retained on the horizontal plate into the pyrolysis zone and positioned or positionable above the horizontal plate.   
     
     
         2 . The gasifier as claimed in  claim 1 , wherein the movable pusher comprises at least one arm extending horizontally above the plate and mounted rotatably about a second vertical axis. 
     
     
         3 . The gasifier as claimed in  claim 2 , wherein the second axis is offset relative to the first axis. 
     
     
         4 . The gasifier as claimed in  claim 2 , further comprising:
 a motor for driving the at least one arm of the pusher in rotation about the second axis; and   first controlling means for controlling the motor to give a rocking motion to the at least one arm about the second axis.   
     
     
         5 . The gasifier as claimed in  claim 4 , wherein the first controlling means is to set an initial angular position and an amplitude of the rocking motion. 
     
     
         6 . The gasifier as claimed in  claim 1 , wherein the first vessel comprises levelling means to at least partially level a top surface of a bed of solid fuel in the pyrolysis zone. 
     
     
         7 . The gasifier as claimed in  claim 6 , wherein the levelling means comprises at least one levelling arm extending horizontally at a level of the top surface of the bed of solid fuel in the pyrolysis zone, the at least one arm being mounted rotatably about a third vertical axis. 
     
     
         8 . The gasifier as claimed in  claim 7 , wherein the levelling means comprises six arms mounted radially at intervals of 60 degrees around a rotating shaft with the third axis. 
     
     
         9 . The gasifier as claimed in  claim 7 , wherein the second axis and the third axis coincide. 
     
     
         10 . The gasifier as claimed in  claim 9 , wherein the at least one arm of the pusher and the at least one levelling arm of the levelling means are mounted on a rotating shaft. 
     
     
         11 . The gasifier as claimed in  claim 3 , further comprising:
 a motor for driving the at least one arm of the pusher in rotation about the second axis; and   first controlling means for controlling the motor to give a rotating motion to the at least one arm about the second axis.   
     
     
         12 . The gasifier as claimed in  claim 11 , wherein the first controlling means is to set an initial angular position and an amplitude of the rotating motion. 
     
     
         13 . The gasifier as claimed in  claim 8 , wherein the second axis and the third axis coincide. 
     
     
         14 . The gasifier as claimed in  claim 9 , wherein the at least one arm of the pusher and the at least one levelling arm of the levelling means are mounted on a rotating shaft. 
     
     
         15 . A unit for production and combustion of gas, comprising a gasifier as claimed in  claim 1  for producing the gas. 
     
     
         16 . A gasifier comprising:
 an inlet to introduce a fuel;   a pyrolysis zone to pyrolyze the fuel;   a plate mounted between the inlet and the pyrolysis zone to hold the fuel;   a pusher mounted between the inlet and the plate to push the fuel from the plate into the pyrolysis zone, the pusher positioned above the plate and movable relative to the plate;   a combustion zone to burn pyrolysis gases from the pyrolysis zone;   a reduction zone to gasify carbonized fuel from the pyrolysis zone; and   an outlet to collect gases produced in the reduction zone.