Devices and Methods for a Pyrolysis and Gasification System for Biomass Feedstock

Abstract

A pyrolysis and gasification system produce a synthesis gas and bio-char from a biomass feedstock. The system includes a feed hopper that has a flow measurement device. The system also includes a reactor that is operable in a gasification mode or a pyrolysis mode. The reactor is configured to receive the biomass feedstock from the feed hopper. The reactor is operable to provide heat to the biomass feedstock from the feed hopper to produce the synthesis gas and bio-char. The system also includes a cyclone assembly. The produced synthesis gas including the bio-char is fed to the cyclone assembly. The cyclone assembly removes a portion of the bio-char from the synthesis gas.

What is claimed is: 
     
         1 . A pyrolysis and gasification system for producing a synthesis gas and bio-char from a biomass feedstock, comprising:
 a feed hopper, wherein the feed hopper comprises a flow measurement device;   a reactor that is operable in a gasification mode or a pyrolysis mode, and wherein the reactor is configured to received the biomass feedstock from the feed hopper, and further wherein the reactor is operable to provide heat to the biomass feedstock from the feed hopper to produce the synthesis gas and bio-char; and   a cyclone assembly, wherein the produced synthesis gas comprising bio-char is fed to the cyclone assembly, and wherein the cyclone assembly removes bio-char from the synthesis gas.   
     
     
         2 . The pyrolysis and gasification system of  claim 1 , wherein the reactor comprises a reactor bed, wherein the reactor bed is fluidized by a fluidizing medium input. 
     
     
         3 . The pyrolysis and gasification system of  claim 1 , wherein the reactor comprises an upper portion and a bottom portion, and wherein the upper portion comprises an increased diameter over a diameter of the bottom portion. 
     
     
         4 . The pyrolysis and gasification system of  claim 1 , wherein the cyclone assembly comprises a first cyclone and a second cyclone. 
     
     
         5 . The pyrolysis and gasification system of  claim 1 , further comprising a pressure swing absorption system, wherein the produced synthesis gas is fed to the pressure swing absorption system to remove contaminants from the synthesis gas. 
     
     
         6 . The pyrolysis and gasification system of  claim 5 , wherein the pressure swing absorption system comprises a first absorber and a second absorber, wherein the second absorber is purged of absorbed contaminants when the first absorber is absorbing contaminants from the synthesis gas, and wherein the first absorber is purged of contaminants when the second absorber is absorbing contaminants from the synthesis gas. 
     
     
         7 . The pyrolysis and gasification system of  claim 6 , wherein the first absorber and the second absorber each comprise an activated carbon section and a molecular sieve section. 
     
     
         8 . The pyrolysis and gasification system of  claim 1 , further comprising a condenser, wherein the synthesis gas is fed to the condenser to produce bio-oil. 
     
     
         9 . The pyrolysis and gasification system of  claim 1 , wherein the bio-char from the cyclone assembly is fed to a char collector. 
     
     
         10 . The pyrolysis and gasification system of  claim 1 , wherein operating conditions of the reactor are adjustable to control production of the bio-char and synthesis gas. 
     
     
         11 . A method for gasification and pyrolysis of a biomass feedstock in a reactor, wherein the reactor comprises bed materials, comprising:
 (A) introducing a fluidizing medium to the bed materials to fluidize the bed materials and to produce a fluidized condition;   (B) heating the bed materials to a desired temperature, wherein the heating is provided by a heat source;   (C) feeding the biomass feedstock to the bed materials, wherein a reaction produces a synthesis gas and bio-char from the biomass feedstock;   (D) controlling the temperature of the bed materials to maintain the fluidized condition in a pyrolysis mode; and   (E) removing the bio-char from the reactor.   
     
     
         12 . The method of  claim 11 , further comprising selecting bed materials of a desired size. 
     
     
         13 . The method of  claim 11 , further comprising removing the heating provided by the heat source when the desired temperature is achieved. 
     
     
         14 . The method of  claim 11 , further comprising determining a feed rate of the biomass feedstock to the bed materials. 
     
     
         15 . The method of  claim 11 , further comprising controlling feed rates of the fluidizing medium and the biomass feedstock to the bed materials. 
     
     
         16 . The method of  claim 11 , further comprising controlling operating conditions to prevent the reaction from proceeding into a combustion mode, wherein the controlling operating conditions comprises increasing a temperature of the reactor by increasing a flow rate of the fluidizing medium and maintaining a feed rate of the biomass feedstock. 
     
     
         17 . The method of  claim 16 , wherein the controlling operating conditions optionally comprises decreasing a temperature of the reactor by increasing a feed rate of the biomass feedstock and maintaining a flow rate of the fluidizing medium. 
     
     
         18 . The method of  claim 11 , further comprising maintaining a minimum air flow rate to maintain the fluidized condition. 
     
     
         19 . The method of  claim 11 , further comprising feeding the synthesis gas to a pressure swing absorption system to remove contaminants from the synthesis gas. 
     
     
         20 . The method of  claim 11 , further comprising feeding the synthesis gas to a condenser to produce bio-oil.