Pyrolyzer furnace apparatus and method for operation thereof

Abstract

A char making apparatus comprises a longitudinal pyrolyzer furnace housing wherein coal-bearing material may be heated to a temperature to fluidize volatile materials therein and plasticize coal in the coal-bearing material. At least two rotatable drive screws are laterally positioned and interleaved within the longitudinal furnace housing and capable of conveying coal-bearing materials through the pyrolyzer furnace housing, each drive screw having a hollow drive shaft and a diverter positioned within the drive shaft to provide heating to the coal-bearing material. A heating jacket about the longitudinal furnace housing provides additional heating to the coal-bearing material. Multiple combustion chambers adjacent the heating jacket and hollow drive shaft burn fluidized volatile materials and exhaust combustion fluids through the jacket and shaft.

What is claimed is: 
     
         1 . A method for making char comprising the steps of:
 a. assembling a longitudinal pyrolyzer furnace housing having at least two rotatable drive screws laterally positioned and interleaved within the longitudinal furnace housing, and capable of conveying coal-bearing materials containing volatile material through the pyrolyzer furnace housing, each drive screw having a hollow drive shaft and a diverter longitudinally positioned within the drive shaft, the diverter forming with an inner surface of each drive shaft an inner passageway capable of directing heat flux to adjacent coal-bearing materials moving through the pyrolyzer furnace to fluidize the volatile material therein and plasticize coal in the coal-bearing material;   b. assembling a heating jacket about the longitudinal furnace housing along at least a portion thereof in fluid communication with combustion fluid from multiple combustion chambers to provide heat flux from combustion fluid moving through the heating jacket to adjacent coal-bearing materials moving through the pyrolyzer furnace to fluidize the volatile material in the coal bearing material and plasticize the coal in the coal bearing material;   c. assembling multiple combustion chambers adjacent the longitudinal pyrolyzer furnace housing capable of burning fluidized volatile material and, if desired, other hydrocarbon fuels, and exhausting combustion fluids through the inner passageway within the hollow drive shaft of the drive screws and the heating jacket of the pyrolyzer furnace housing to fluidize the volatile material in the coal bearing material and plasticize the coal in the coal bearing material; and   d. rotating the drive screws to cause coal-bearing material containing volatile materials to move through the longitudinal pyrolyzer furnace housing to be heated by the heat flux from the combustion fluid to fluidize volatile material in the coal-bearing material and plasticize the coal in the coal-bearing material.   
     
     
         2 . The method of making char as claimed in  claim 1 , where the flow of combustion fluid through the inner passageways and heating jacket are in the same direction as the movement of the coal-bearing materials through the pyrolyzer furnace housing. 
     
     
         3 . The method of making char as claimed in  claim 1 , further comprising the step of: providing a turbulent flow of combustion fluids through the inner passageways and the heating jacket having a Reynolds Number greater than 4000. 
     
     
         4 . The method of making char as claimed in  claim 1 , further comprising the step of: tapering outer walls of the hollow shafts of the drive screws downstream to cause the coal-bearing material to be compressed as it moves through the pyrolyzer furnace housing to compact the char before exiting the pyrolyzer furnace housing. 
     
     
         5 . The method of making char as claimed in  claim 1 , further comprising the step of: reducing the cross sectional area of the portion of the pyrolyzer furnace housing through which the coal-bearing material moves in the direction of movement of the coal-bearing material through the housing to compress the coal-bearing materials as it moves through the pyrolyzer furnace housing to compact the char before exiting the pyrolyzer furnace housing. 
     
     
         6 . The method of making char as claimed in  claim 1 , the step involve heating the volatile materials in the coal-bearing material and coal in the coal bearing material to a temperature within a range of approximately 650° F. to 1300° F. 
     
     
         7 . The method of making char as claimed in  claim 1 , further comprising the step of: raising an end of the pyrolyzer furnace housing to provide an elevation in the direction of travel of the coal-bearing material through the pyrolyzer furnace housing. 
     
     
         8 . The method of making char as claimed in  claim 1 , where step a. involves: assembling at least three drive screws laterally positioned within the pyrolyzer furnace housing, with each screw being positioned such that each drive screw interleaves at least one other screw. 
     
     
         9 . The method of making char as claimed in  claim 1 , where the step of assembling pyrolyzer furnace housing includes forming at least two zones along its length, where the first zone is capable of fluidizing volatile materials, and the second zone is capable of mixing supplemental materials into the coal-bearing materials, and plasticizing coal in the coal-bearing material in the second or subsequent zone. 
     
     
         10 . The method of making char as claimed in  claim 1 , where the step of assembling the pyrolyzer furnace housing includes forming at least two zones along its length, where the first zone is capable of fluidizing volatile materials, and at least one of the subsequent zones are capable of plasticizing coal in the coal-bearing material. 
     
     
         11 . A method of making char comprising the steps of:
 a. assembling a longitudinal pyrolyzer furnace housing having at least two rotatable drive screws laterally positioned and interleaved within the longitudinal furnace housing, and capable of conveying coal-bearing materials containing volatile material through the pyrolyzer furnace housing, each drive screw having a hollow drive shaft and a diverter longitudinally positioned within the drive shaft, the diverter forming with an inner surface of each drive shaft an inner passageway to direct heat flux from combustion fluid moving through the inner passageway to adjacent the coal-bearing materials moving through the pyrolyzer furnace to fluidize the volatile material in the coal bearing material and plasticize coal in the coal-bearing material, and having double outer walls in the furnace housing at least partially around the rotatable drive screws and forming an outer passageway between the outer walls, the outer passageway capable of conveying a flow of combustion fluid adjacent the coal-bearing materials through the pyrolyzer furnace housing to fluidize the volatile material therein;   b. assembling combustion chambers adjacent the longitudinal pyrolyzer furnace housing capable of burning fluidized volatile material and, if desired, other hydrocarbon fuels, and conveying combustion fluids through the inner passageway within the hollow drive shaft of the rotatable drive screws and the outer passageway in the pyrolyzer furnace housing to provide heat flux to fluidize the volatile material in the coal bearing material and plasticize coal in the coal-bearing material; and   c. rotating the drive screws to cause coal-bearing material containing volatile materials to move through the longitudinal pyrolyzer furnace housing and be heated to a temperature to fluidize volatile materials in the coal bearing material and plasticize coal in the coal-bearing material.   
     
     
         12 . The method of making char as claimed in  claim 11 , where the flow of combustion fluid through the inner passageways and outer passageways in the furnace housing are in the same direction as the movement of the coal-bearing materials through the pyrolyzer furnace housing. 
     
     
         13 . The method of making char as claimed in  claim 11 , further comprising the step of: providing a turbulent flow of combustion fluids through the inner passageway and the outer passageway having a Reynolds Number greater than 4000. 
     
     
         14 . The method of making char as claimed in  claim 11 , further comprising the step of: tapering outer walls of the hollow shafts of the drive screws downstream to cause the coal-bearing material to be compressed as it moves through the pyrolyzer furnace housing to compact the char before exiting the pyrolyzer furnace housing. 
     
     
         15 . The method of making char as claimed in  claim 11 , further comprising the step of: reducing the cross sectional area of the portion of the pyrolyzer furnace housing through which the coal-bearing material moves in the direction of movement of the coal-bearing material through the housing to compress the coal-bearing materials as it moves through the pyrolyzer furnace housing to compact the char before exiting the pyrolyzer furnace housing. 
     
     
         16 . The method of making char as claimed in  claim 11 , the steps involve heating the volatile materials in the coal-bearing material and coal in the coal bearing material to a temperature within a range of approximately 650° F. to 1300° F. 
     
     
         17 . The method of making char as claimed in  claim 11 , further comprising the step of: raising an end of the pyrolyzer furnace housing to provide an elevation in the direction of travel of the coal-bearing material through the pyrolyzer furnace housing. 
     
     
         18 . The method of making char as claimed in  claim 11 , where step a. involves: assembling at least three drive screws laterally positioned within the pyrolyzer furnace housing, with each screw being positioned to overlap with at least one other screw. 
     
     
         19 . The method of making char as claimed in  claim 11 , where the step of assembling pyrolyzer furnace housing include forming at least two zones along its length, where the heat flux is capable of fluidizing volatile materials in the first zone, and the second zone is capable of mixing supplemental materials into the coal-bearing materials, and the heat flux is capable of plasticizing coal in the coal-bearing material in the second and/or subsequent zones. 
     
     
         20 . The method of making char as claimed in  claim 11 , where the step of assembling the pyrolyzer furnace housing includes forming at least two zones along its length, where the heat flux is capable of fluidizing volatile materials in the first zone, and the heat flux are capable of plasticizing coal in the coal-bearing material in at least one of the subsequent zones.