System and process for biomass treatment

Abstract

A system including an apparatus is presented for treatment of biomass that allows successful biomass treatment at a high solids dry weight of biomass in the biomass mixture. The design of the system provides extensive distribution of a reactant by spreading the reactant over the biomass as the reactant is introduced through an injection lance, while the biomass is rotated using baffles. The apparatus system to provide extensive assimilation of the reactant into biomass using baffles to lift and drop the biomass, as well as attrition media which fall onto the biomass, to enhance the treatment process.

1 . A system for batch processing biomass comprising: 
 a) an apparatus comprising: 
 i) a cylindrical reaction vessel with an opening on at least one end;  
 ii) one or more baffles attached to the interior of said vessel;  
 iii) attrition media comprising pellets free-floating in the interior of the reaction vessel;  
 iv) a cover for said vessel open end comprising one or more ports; and  
 v) an injection lance comprising means for delivering a processing reactant, wherein said means is an injection lance extending the length of the reaction vessel and connecting to a first port in the cover of iv); and  
   b) means for rotating the baffles of the vessel.    
     
     
         2 . The apparatus of  claim 1  wherein the attrition media occupy less than about 10% of the volume of the reaction vessel.  
     
     
         3 . The apparatus of  claim 1 , further comprising a rotary joint connected to a port in the reaction vessel cover.  
     
     
         4 . The apparatus of  claim 1  wherein a second port is a port for adding reactants to the reaction vessel, for sampling the contents of the reaction vessel, or both.  
     
     
         5 . The apparatus of  claim 1 , wherein said vessel is composed of a non-corrosive material capable of withstanding temperatures ranging from about −10° C. to about 220° C.  
     
     
         6 . The apparatus of  claim 5 , wherein the vessel is capable of withstanding temperatures ranging from about 4° C. to about 170° C.  
     
     
         7 . The apparatus of  claim 5 , wherein said material is stainless steel.  
     
     
         8 . The apparatus of  claim 1 , wherein said vessel is composed of a non-corrosive material capable of withstanding pressures up to about 1200 kPa.  
     
     
         9 . The apparatus of  claim 8 , wherein the vessel is capable of withstanding pressures up to about 310 kPa.  
     
     
         10 . The apparatus of  claim 1 , wherein said baffles are attached at perpendicular angles to the interior surface of the reaction vessel.  
     
     
         11 . The apparatus of  claim 1 , wherein said processing reactant is an aqueous solution comprising ammonia.  
     
     
         12 . The apparatus of  claim 1 , wherein said processing reactant is a saccharifying enzyme mixture.  
     
     
         13 . The system of  claim 1 , further comprising means for temperature control.  
     
     
         14 . The system of  claim 13 , wherein said means for temperature control is a temperature controlling jacket or an external incubator.  
     
     
         15 . The system of  claim 1 , further comprising a vacuum source connected to the port.  
     
     
         16 . The system of  claim 1 , wherein said system provides for treatment of biomass at high dry biomass concentrations ranging from about 15 weight percent to about 80 weight percent of a biomass-reactant mixture.  
     
     
         17 . The system of  claim 1 , wherein said system provides for treatment of biomass at high dry biomass concentrations ranging from about 15 weight percent to about 60 weight percent of a biomass-reactant mixture.  
     
     
         18 . The system of  claim 1 , wherein said means for rotation is rollers, a shaft and crank, belts, wheels, or trunnion bearings.  
     
     
         19 . A process for treating biomass comprising: 
 a) introducing biomass to the reaction vessel of the apparatus of  claim 1;     b) introducing a processing reactant to the reaction vessel; and    c) assimilating said processing reactant into said biomass by rotating the baffles of the reaction vessel whereby the baffles lift and drop the attrition media.    
     
     
         20 . The process of  claim 19 , wherein said process is a biomass pretreatment process.  
     
     
         21 . The process of  claim 20 , wherein said processing reactant is an aqueous solution comprising ammonia.  
     
     
         22 . The process of  claim 20 , wherein said process is a saccharification process.  
     
     
         23 . The process of  claim 22 , wherein said processing reactant is a saccharification enzyme mixture.  
     
     
         24 . A process for treating biomass comprising: 
 b) pretreating biomass in the reaction vessel of the apparatus of  claim 1 , producing pretreated biomass;    c) adjusting the temperature and pH of the pretreated biomass of (a) in the reaction vessel; and    d) saccharifying the adjusted pretreated biomass of (b) in the reaction vessel.    
     
     
         25 . A process for pretreating biomass comprising: 
 a) introducing biomass to the reaction vessel of the apparatus of  claim 1;     b) contacting said biomass with an aqueous solution comprising ammonia to form a biomass-aqueous ammonia mixture in the reaction vessel, wherein the ammonia is present at a concentration at least sufficient to maintain alkaline pH of the biomass-aqueous ammonia mixture but wherein said ammonia is present at less than about 12 weight percent relative to dry weight of biomass, and further wherein the dry weight of biomass is at a high solids concentration of at least about 15 weight percent relative to the weight of the biomass-aqueous ammonia mixture.    
     
     
         26 . A process for saccharifying pretreated biomass at high dry biomass concentration, comprising: 
 a) providing biomass, wherein said biomass has optionally been pretreated to provide a readily saccharifiable composition;    b) providing an enzyme consortium capable of hydrolyzing the biomass of (a);    c) assimilating the enzymes of (b) into the biomass of (a) in the apparatus of  claim 1 .    
     
     
         27 . The process of  claim 26 , wherein fermentable sugars are produced.  
     
     
         28 . The process of  claim 26 , wherein the dry weight of biomass is at high solids concentration of at least about 15 weight percent relative to the weight of the biomass-reactant mixture.  
     
     
         29 . The process of claims  25  or  26 , wherein said biomass is selected from the group consisting of switchgrass, waste paper, sludge from paper manufacture, corn grain, corn cobs, corn husks, corn stover, grasses, wheat, wheat straw, hay, barley, barley straw, rice straw, sugar cane bagasse, sorghum, soy, components obtained from processing of grains, trees, branches, roots, leaves, wood chips, sawdust, shrubs and bushes, vegetables, fruits, flowers and animal manure.  
     
     
         30 . The process of  claim 29  wherein biomass is selected from the group consisting of corn cobs, corn stover, corn husks, sugar cane bagasse, sawdust, switchgrass, wheat straw, hay, rice straw, and grasses.  
     
     
         31 . The process of  claim 30 , wherein biomass is selected from the group consisting of corn cobs, corn stover, sawdust, and sugar cane bagasse.  
     
     
         32 . The process of claims  25  or  26 , wherein said biomass is derived from multiple feedstocks.  
     
     
         33 . A method for optimizing a treatment process comprising: 
 a) introducing biomass to the reaction vessel of the apparatus of  claim 1;     b) varying treatment conditions in the reaction vessel;    c) sampling the treated biomass via said one or more ports under said varying treatment conditions; and    d) testing said samples to determine optimal treatment conditions for processing biomass.    
     
     
         34 . The method of  claim 33 , wherein said varying conditions include, pH, temperature, processing reactants and concentrations of processing reactants, percent initial dry weight of biomass in the biomass-reactant mixture, type and form of biomass, type of inert atmosphere, pressure, feed strategies for process reactants, and processing time.  
     
     
         35 . The method of  claim 33 , wherein said treatment process is a saccharification process.  
     
     
         36 . The method of  claim 33 , wherein said treatment process is a pretreatment process.