Apparatus for biomass torrefaction, manufacturing a storable fuel from biomass and producing offsets for the combustion products of fossil fuels

Abstract

Apparatus for biomass torrefaction which includes a serpentine elongated housing, the housing having three generally U-shaped axial portions having first and second axial extremities and an intermediate section, the first and second axial extremities are disposed in normal use at a higher elevation than the first and second axial extremities, the intermediate section being configured for holding a liquid. Other forms of the invention include the method for biomass torrefaction which includes providing a quantity of biomass, providing a liquid heat transfer fluid, providing at least a first housing for holding the heat transfer liquid, elevating the temperature of the liquid heat transfer liquid, heat treating the biomass by passing it through the heat transfer liquid in the first housing at a temperature and duration sufficient to accomplish torrefaction of the wood. In some forms of the method, the process further includes the step of pelletizing the biomass prior to performing the treating step.

1 . Apparatus for biomass torrefaction which comprises a serpentine elongated housing, said housing having at least a first generally U-shaped axial portion having first and second axial extremities and an intermediate section, the first and second axial extremities are disposed in normal use at a higher elevation than the first and second axial extremities, said intermediate section being configured for holding a liquid whereby axial movement of wood of associated wood from said first axial extremity to said second axial extremity immerses the wood in a liquid in said intermediate section. 
     
     
         2 . The apparatus as described in  claim 1  wherein said serpentine elongated housing further includes a second generally U-shaped axial portion having first and second axial extremities and an intermediate section, the first and second axial extremities thereof being disposed in normal use at a higher elevation than the first and second axial extremities thereof, said intermediate section being configured for holding a liquid, said second generally U-shaped axial portion being coupled to said first generally U-shaped axial portion by a first elevated axial section of said housing whereby said first and second generally U-shaped axial portions are disposed in fluid communication. 
     
     
         3 . The apparatus as described in  claim 2  wherein said serpentine elongated housing further includes a third generally U-shaped axial portion having first and second axial extremities and an intermediate section, the first and second axial extremities thereof being disposed in normal use at a higher elevation than the first and second axial extremities thereof, said intermediate section being configured for holding a liquid, said third generally U-shaped axial portion being coupled to said second generally U-shaped axial portion by a second elevated axial section of said housing whereby said first, second and third generally U-shaped axial portions are disposed in fluid communication. 
     
     
         4 . The apparatus as described in  claim 1  wherein said first axial portion is a pre-heat portion. 
     
     
         5 . The apparatus as described in  claim 2  wherein said second axial portion is a heat treatment section. 
     
     
         6 . The apparatus as described in  claim 3  wherein said third axial section is a cooling section. 
     
     
         7 . The apparatus as described in  claim 2  further including a vent in said first elevated axial sections whereby moisture and volatile organic compounds can escape. 
     
     
         8 . The apparatus as described in  claim 3  further including respective first and second vents in said first and second elevated axial sections whereby moisture and volatile organic compounds can escape. 
     
     
         9 . The apparatus as described in  claim 1  further including a wire mesh enclosure for containing biomass in a pellet form, said enclosure being dimensioned and configured for passage through said serpentine elongated housing. 
     
     
         10 . The apparatus as described in  claim 3  including a plurality of wire mesh enclosures for containing biomass in a pellet form, each of said enclosures being dimensioned and configured or axial movement in said serpentine elongated housing. 
     
     
         11 . The apparatus as described in  claim 3  further including a conveyor for serially moving wire mesh enclosures through the axial extent of the serpentine elongated housing. 
     
     
         12 . The apparatus as described in  claim 11  wherein said conveyor includes elongated members joining respective wire mesh enclosures whereby a succession of alternating elongation members and wire mesh enclosures are joined together. 
     
     
         13 . The apparatus as described in  claim 12  wherein each of said elongated members is a chain. 
     
     
         14 . The apparatus as described in  claim 3  further including a heat recovery system for recovering heat added to an associated biomass being heat-treated in said apparatus. 
     
     
         15 . The apparatus as described in  claim 3  further including apparatus for the raising the temperature of an associated heat transfer fluid within said second portion to a temperature in the range of substantially 380 to 550° F.