Static solid state bioreactor and method for using same

Abstract

A static solid state bioreactor and method of using same. The bioreactor comprises a vessel having an upper end and a lower end, the upper end having a sealable opening. A gas distribution system in communication with the upper end and the lower end of the vessel. A liquid distribution system in communication with the upper end of the vessel. A liquid recovery system in communication with the lower end of the vessel. A material removal system disposed at the lower end of the vessel for removing biomass from the vessel.

1 . A static solid state bioreactor, the bioreactor comprising:
 a vessel having an upper end and a lower end, the upper end having a sealable opening;   a gas distribution system in communication with the upper end and the lower end of the vessel;   a liquid distribution system in communication with the upper end of the vessel;   a liquid recovery system in communication with the lower end of the vessel; and   a material removal system disposed at the lower end of the vessel for removing biomass residue from the vessel.   
     
     
         2 . The bioreactor of  claim 1 , wherein the vessel further comprises a plurality of openings located on the lower end wherein the gas distribution system communicates with the vessel at the lower end through the plurality of openings. 
     
     
         3 . The bioreactor of  claim 1 , wherein the vessel further comprises a plurality of openings located on the lower end wherein the liquid recovery system communicates with the vessel at the lower end through the plurality of openings. 
     
     
         4 . The bioreactor of  claim 1 , wherein the lower end of the vessel is conically shaped. 
     
     
         5 . The bioreactor of  claim 4 , wherein the biomass opening is located at an apex of the conically shaped lower end. 
     
     
         6 . The bioreactor of  claim 5 , wherein the material reclaim system further comprises an auger driven by a motor wherein the auger protrudes into the vessel through the opening at the apex and extends up towards a perimeter of a base of the conically shaped lower end. 
     
     
         7 . The bioreactor of  claim 4 , wherein the vessel further comprises a plurality of openings located on the lateral surface of the conically shaped lower end. 
     
     
         8 . The bioreactor of  claim 7 , wherein the gas distribution system is in communication with the lower end of the vessel through the plurality of openings. 
     
     
         9 . The bioreactor of  claim 8 , wherein the liquid recovery system is in communication with the lower end of the vessel through the plurality of openings. 
     
     
         10 . The bioreactor of  claim 7 , further comprising at least one screen disposed on the lower end of the vessel and covering the plurality of openings. 
     
     
         11 . The bioreactor of  claim 7 , further comprising a plurality of screens configured to fit within and cover one of the plurality of openings in the lower end of the vessel. 
     
     
         12 . The bioreactor of  claim 1 , wherein the gas distribution system further comprises:
 at least one fan;   a first duct in communication with the upper end of the vessel and the fan; and   a second duct in communication with the lower end of the vessel and the fan.   
     
     
         13 . The bioreactor of  claim 12 , wherein the gas distribution system further comprises at least one valve, the at least one valve in communication with the at least one fan, wherein the at least one valve can selectively connect an intake and an output from the at least one fan to the first duct and the second duct and change a direction of a gas flow through the vessel. 
     
     
         14 . The bioreactor of  claim 1 , wherein the liquid collection system is in communication with the liquid distribution system wherein a liquid effluent from the bioreactor can be recycled. 
     
     
         15 . The bioreactor of  claim 10 , wherein the at least one screen is a wedge wire screen. 
     
     
         16 . The bioreactor of  claim 15 , wherein the wedge wire screen further comprises a plurality of wires oriented to run towards a direction of material removal. 
     
     
         17 . A method of performing static solid state fermentation, the method comprising the steps of:
 a. mixing a bulking agent with a biomass to form a mixture;   b. adding the mixture to a static solid state bioreactor;   b. irrigating the mixture with an aqueous solution;   c. flowing a gas through the mixture; and,   d. maintaining a microorganism supporting environment within the mixture by calculating a specific heat of an aqueous solution flow, calculating a specific heat of a gas flow, and balancing the aqueous solution flow with the gas flow.   
     
     
         18 . The method according to  claim 17 , further comprising the step of maintaining a ratio of mass flow per cross sectional area per unit time of the gas flow to the aqueous solution flow between 0.25 and 0.4. 
     
     
         19 . The method according to  claim 17 , further comprising the step of adding an inoculum comprising at least one microorganism to the biomass prior to the step of mixing a bulking agent with a biomass. 
     
     
         20 . The method according to  claim 19 , further comprising the step of adding one or more enzymes to the biomass prior to the step of adding an inoculum to the biomass. 
     
     
         21 . The method according to  claim 20 , further comprising the step of adding an antibiotic to the biomass prior to the step of adding enzymes to the biomass. 
     
     
         22 . The method according to  claim 17 , further comprising the step of collecting the liquid solution from a lower end of the biomass and recycling the liquid solution back on to an upper end of the mixture. 
     
     
         23 . The method according to  claim 22 , further comprising the step of treating the liquid solution to improve quality before recycling the liquid solution back on to an upper end of the mixture. 
     
     
         24 . The method according to  claim 17 , wherein the bulking agent maintains a hydraulic conductivity of the mixture greater than 10 −4  cm/sec. 
     
     
         25 . The method according to  claim 17 , wherein the bulking agent limits the gas flow back-pressure to less than 200 mm of water head. 
     
     
         26 . The method according to  claim 17 , further comprising the step of reversing the direction of a gas flow through the mixture. 
     
     
         27 . A non-stirred solid state bioreactor, comprising:
 a hollow body for stacking biomass therein, the stacked biomass being stored within the hollow body under conditions suitable for fermentation, the hollow body having a lower end and an upper end, the lower end being perforated to allow the a flow of gas and a liquid through the stacked biomass, the upper end having at least one sealable opening for the stacking of biomass within the hollow body;   a passageway for removal of decomposed biomass material at the lower end of the hollow body;   a material removal system operatively provided within the hollow body at the lower end, the material removal system configured to direct the flow of decomposed biomass material toward the passageway during unloading of the hollow body;   a gas delivery system coupled to the upper end and the lower end of the hollow body and configured to flow gas through the stacked biomass from the lower end to the upper end and from the upper end to the lower end;   an irrigation system disposed within the hollow body proximate to the upper end of the vessel and configured to irrigate the stacked biomass from above; and   a system for collecting liquid effluent that drains from the stacked biomass operatively provided proximate to the perforated lower end.   
     
     
         28 . The bioreactor vessel of  claim 27 , wherein the material removal system further comprises at least one auger. 
     
     
         29 . The bioreactor vessel of  claim 27 , wherein the hollow body is sealed and configured for anaerobic bioreactor operation. 
     
     
         30 . A bioreactor for performing static solid state fermentation of biomass, the bioreactor comprising:
 a vessel having an upper end and a lower end, the lower end having a plurality of openings and a material removal port,   a plurality of gas ports in communication with a gas distribution system and in communication with the plurality of openings in the lower end of the vessel;   a plurality of liquid ports in communication with a liquid collection system and in communication with the plurality of openings in the lower end of the vessel;   at least one screen disposed in the lower end of the vessel covering the plurality of openings.   
     
     
         31 . The bioreactor of  claim 30 , wherein the at least one screen is a wedge wire screen. 
     
     
         32 . The bioreactor of  claim 30 , wherein the at least one screen comprises a plurality of wires oriented to run towards the material removal port. 
     
     
         33 . The bioreactor of  claim 30 , further comprising a plurality of manifolds, the plurality of manifolds being disposed to connect the plurality of openings with the plurality of gas ports and the plurality of liquid ports. 
     
     
         34 . The bioreactor of  claim 33 , wherein at least one gas port of the plurality of gas ports is located above at least one liquid port of the plurality of liquid ports on at least one manifold of the plurality of manifolds. 
     
     
         35 . The apparatus of  claim 14 , wherein the liquid effluent is treated by physical means before recycling. 
     
     
         36 . The apparatus of  claim 14 , wherein the liquid effluent is treated by chemical means before recycling. 
     
     
         37 . The apparatus of  claim 14 , further comprising a means for treating the effluent discharge to improve quality before recycling. 
     
     
         38 . A bioreactor for producing a gaseous fuel from a biomass material, the bioreactor comprising:
 a gas tight vessel having an upper end and a lower end, the upper end having a sealable opening;   at least one fan;   a duct, the duct disposed on the upper end of the vessel, the lower end of the vessel, and the at least one fan, wherein the vessel is in communication with the at least one fan through the duct;   at least one valve, the at least one valve disposed along a length of the duct wherein the at least one valve can change a gas flow direction and cause the gas to flow in a direction from the lower end of the vessel to the upper end of the vessel and in a direction from the upper end of the vessel to the lower end of the vessel.   
     
     
         39 . The bioreactor of  claim 38 , where the at least one valve further comprises a second valve disposed along the length of the duct on an input side of the at least one fan, wherein oxygen can be introduced into the bioreactor by opening the second valve. 
     
     
         40 . A bioreactor for producing a gaseous fuel from a biomass material, the bioreactor comprising:
 a plurality of gas tight vessels having an upper end and a lower end, the upper end having a sealable opening;   a gas distribution system in communication with the upper end and the lower end of the plurality of vessels wherein a gas can be recycled from a first vessel of the plurality of vessels to a second vessel of the plurality of vessels.   
     
     
         41 . A method of producing a gaseous fuel from a biomass material, the method comprising the steps of:
 a. preparing a first volume of biomass for reaction;   b. flowing a gas from a second volume of reacting biomass through the first volume of biomass;   
     
     
         42 . A bioreactor for producing a gaseous fuel from a biomass material, the bioreactor comprising:
 a gas tight volume having an upper end and a lower end;   a mixture of biomass and bulking agent disposed within the gas tight volume;   a gas distribution system in communication with the upper end and lower end of the gas tight volume;   a liquid distribution system in communication with the upper end of the gas tight volume;   a liquid recovery system in communication with the lower end of the gas tight volume,   wherein a microorganism supporting environment is maintained by balancing a counter-current flow of gas through the mixture from the gas distribution system with a counter-current flow of fluid through the mixture from the liquid distribution system to the liquid recovery system.   
     
     
         43 . The bioreactor of  claim 42 , wherein a hydraulic conductivity of the mixture is maintained greater than 10 −4  cm/sec. 
     
     
         44 . The bioreactor of  claim 42 , wherein the hydraulic conductivity of the mixture limits the gas flow back-pressure to less than 200 mm of water head. 
     
     
         45 . The method according to  claim 17 , wherein a product of fermentation is a biogas. 
     
     
         46 . The method according to  claim 45 , wherein the biogas is methane. 
     
     
         47 . The method according to  claim 17 , further comprising the step of collecting a liquid effluent from the static solid state bioreactor. 
     
     
         48 . The method according to  claim 47 , wherein the liquid effluent contains alcohol. 
     
     
         49 . The method according to  claim 47 , wherein the liquid effluent contains ethanol.