System and method for continuously treating biomass

Abstract

A continuous biomass pretreatment system and method is provided. The system comprises a pipe reactor having an input end, an output end, an interior and an exterior. The pipe reactor does not have a mixing component that passes from the interior to the exterior and rotates with respect to the pipe. The system further comprises a pump in communication with the input end of the pipe reactor, a valve in communication with the output end of the pipe reactor, and a flash vessel having an input opening in communication with the output of the valve.

1 . A system for continuously treating biomass, the system comprising:
 a pipe reactor having an input end and an output end and an interior and an exterior wherein the pipe reactor does not have a mixing component that passes from the interior to the exterior and rotates with respect to the pipe;   a pump having an input side and an output side wherein the output side of the pump is in communication with the input end of the pipe reactor;   a valve having an input and an output wherein the output end of the pipe reactor is in communication with the input of the a valve; and   a flash vessel having an input opening and an output opening wherein the output of the valve is in communication with the input opening of the at least one flash vessel.   
     
     
         2 . The system of  claim 1 , wherein the valve is a choke valve. 
     
     
         3 . The system of  claim 1 , further comprising a static mixer disposed within the interior of the pipe reactor. 
     
     
         4 . The system of  claim 1 , further comprising a static mixer disposed within the interior of the pipe reactor and rigidly affixed to the pipe reactor. 
     
     
         5 . The system of  claim 1 , further comprising a counter current splash vessel in communication with the input side of the pump. 
     
     
         6 . The system of  claim 5 , wherein the counter current splash vessel further comprises a steam input. 
     
     
         7 . The system of  claim 6 , wherein the flash vessel further comprises a steam output in communication with the counter current splash vessel steam input and wherein steam is recycled from the flash vessel to the counter current splash vessel. 
     
     
         8 . The system of  claim 1 , wherein the pump is capable of handling pressures between about 350 and 450 pounds per square inch, temperatures between about 120 and 220° C., and a biomass slurry that is about 50% to 90% solids by mass. 
     
     
         9 . A method of continuously treating biomass, the method comprising the steps of:
 a. pumping a biomass slurry with a pump into a pipe reactor at a reaction pressure wherein the pipe reactor does not have a mixing component that passes from the interior to the exterior and rotates with respect to the pipe;   b. heating the biomass within the pipe reactor to a reaction temperature;   c. ejecting the heated biomass from the pipe reactor through a valve into a flash vessel to rapidly depressurize the biomass; and   d. maintaining a constant flow rate through the pipe reactor, wherein the biomass reaches the reaction temperature before exiting the pipe reactor.   
     
     
         10 . The method according to  claim 9 , further comprising the step of pre-heating the biomass in a counter current splash vessel before the pumping step. 
     
     
         11 . The method according to  claim 10 , further comprising the step of recovering steam from the flash vessel and recycling the recovered steam to the counter current splash vessel to pre treat the biomass. 
     
     
         12 . The method according to  claim 9 , wherein the valve is a choke valve. 
     
     
         13 . The method according to  claim 9 , further comprising the step of injecting a reagent on an input side of the pump. 
     
     
         14 . The method according to  claim 9 , wherein the pump is capable of handling pressures between about 350 and 450 pounds per square inch, temperatures between about 120 and 220° C., and a biomass slurry that is about 50% to 90% solids by mass. 
     
     
         15 . The method according to  claim 9 , wherein the heating step is performed by injecting steam into the pipe reactor. 
     
     
         16 . A method of continuously treating biomass, the method comprising the steps of:
 a. a high solids biomass slurry into a pipe reactor at a reaction pressure wherein the pipe reactor has no motor driven stirring method and wherein the pipe reactor has a plurality of sealable openings for flowing biomass and steam;   b. injecting steam into the pipe reactor to heat the biomass;   c. ejecting the heated biomass from the pipe reactor through a valve into a flash vessel to rapidly depressurize the biomass; and   d. maintaining a constant flow rate through the pipe reactor, wherein the biomass reaches a reaction temperature before exiting the pipe reactor by continuously performing the pumping, injecting, and ejecting steps.   
     
     
         17 . The method according to  claim 16 , further comprising the step of pre-heating the biomass in a counter current splash vessel before the pumping step. 
     
     
         18 . The method according to  claim 17 , further comprising the step of recovering steam from the flash vessel and recycling the recovered steam to the counter current splash vessel in the pre-heating step. 
     
     
         19 . The method according to  claim 17 , wherein the valve is a choke valve. 
     
     
         20 . The method according to  claim 17 , further comprising the step of injecting a reagent on an input side of the pump. 
     
     
         21 . The method according to  claim 17 , wherein the pump is capable of handling pressures between about 350 and 450 pounds per square inch and temperatures between about 120 and 220° C., and a biomass slurry that is about 50% to 90% solids by mass.