Pyrolysis oil and other combustible compositions from microbial biomass

Abstract

Oleaginous microbial biomass is subjected to pyrolysis to make microbial pyrolysis oil for use as a fuel or is otherwise formed into combustible products for the generation of heat and/or light.

1 . A gasification method employing biomass from an oleaginous microbe as a feedstock, wherein said biomass comprises spent microbial biomass, less than about 20% protein by dry cell weight, and about 1-20% lipid by dry cell weight, said method comprising the steps of heating said biomass at a temperature of from about 200 to 1400 degrees C. in an atmosphere containing less than 3% V/V oxygen to produce a gas containing a mixture of hydrocarbons. 
     
     
         2 . The method of  claim 1  comprising the additional step of cooling said gas to form a pyrolysis oil. 
     
     
         3 . The method of  claim 1 , wherein the gas produced or an oil produced from the gas is used as an energy source in the gasification of additional biomass. 
     
     
         4 . (canceled) 
     
     
         5 . A burnable torrefied composition comprising biomass from an oleaginous microbe produced by a method comprising the steps of: (1) heating said biomass under substantially oxygen free conditions at a temperature of from about 200° C. to about 280° C.; (2) maintaining said heating step for a period of from about 0.25 hours to about 10 hours; (3) cooling the heated product; and (4) recovering the burnable torrefied composition. 
     
     
         6 . A solid, non-torrefied burnable fuel composition comprising combustible biomass from an oleaginous microbe shaped into a log or pellet suitable for burning in a fireplace, stove, oven, or furnace. 
     
     
         7 . The composition of  claim 6  that further comprises a combustible binder or a crackling additive or both. 
     
     
         8 . The composition of any of  claim 5 , wherein the biomass is spent microbial biomass. 
     
     
         9 . The composition of  claim 8 , wherein said biomass makes up by weight from about 5% to about 100% of said burnable composition. 
     
     
         10 . The composition of  claim 5 , wherein said composition further comprises non-microbial cellulosic or lignocellulosic material. 
     
     
         11 . The composition of  claim 5 , wherein said biomass comprises less than about 10% protein by dry cell weight and about 1-10% lipid by dry cell weight. 
     
     
         12 . The composition of  claim 11 , wherein said biomass comprises less than about 10% protein by dry cell weight and about 1-5% lipid by dry cell weight. 
     
     
         13 . The composition of  claim 5 , wherein the biomass was obtained from an oleaginous microbe cultured under heterotrophic conditions. 
     
     
         14 . The composition of  claim 13 , wherein the biomass is selected from microalgal biomass and oleaginous yeast biomass. 
     
     
         15 . The composition of  claim 5 , wherein the biomass is milled or processed to generate particles of a between about 1 mm and about 50 mm. 
     
     
         16 . The composition of  claim 5 , wherein the biomass is derived from a microalgae selected from the group consisting of  Achnanthes orientalis, Agmenellum, Amphiprora hyaline, Amphora coffeiformis, Amphora coffeiformis linea, Amphora coffeiformis punctata, Amphora coffeiformis taylori, Amphora coffeiformis tenuis, Amphora delicatissima, Amphora delicatissima capitata, Amphora  sp.,  Anabaena, Ankistrodesmus, Ankistrodesmus falcatus, Boekelovia hooglandii, Borodinella  sp.,  Botryococcus braunii, Botryococcus sudeticus, Carteria, Chaetoceros gracilis, Chaetoceros muelleri, Chaetoceros muelleri subsalsum, Chaetoceros  sp.,  Chlorella anitrata, Chlorella Antarctica, Chlorella aureoviridis, Chlorella candida, Chlorella capsulate, Chlorella desiccate, Chlorella ellipsoidea, Chlorella emersonii, Chlorella fusca, Chlorella fusca  var.  vacuolata, Chlorella glucotropha, Chlorella infusionum, Chlorella infusionum  var.  actophila, Chlorella infusionum  var.  auxenophila, Chlorella kessleri, Chlorella lobophora  (strain SAG 37.88),  Chlorella luteoviridis, Chlorella luteoviridis  var.  aureoviridis, Chlorella luteoviridis  var.  lutescens, Chlorella miniata, Chlorella minutissima, Chlorella mutabilis, Chlorella nocturna, Chlorella parva, Chlorella photophila, Chlorella pringsheimii, Chlorella protothecoides  (including any of UTEX strains 1806, 411, 264, 256, 255, 250, 249, 31, 29, 25, and CCAP strains 211/17 and 211/8d),  Chlorella protothecoides  var.  acidicola, Chlorella regularis, Chlorella regularis  var.  minima, Chlorella regularis  var.  umbricata, Chlorella reisiglii, Chlorella saccharophila, Chlorella saccharophila  var.  ellipsoidea, Chlorella salina, Chlorella simplex, Chlorella sorokiniana, Chlorella  sp.,  Chlorella sphaerica, Chlorella stigmatophora, Chlorella vanniellii, Chlorella vulgaris, Chlorella vulgaris, Chlorella vulgaris f. tertia, Chlorella vulgaris  var.  autotrophica, Chlorella vulgaris  var.  viridis, Chlorella vulgaris  var.  vulgaris, Chlorella vulgaris  var.  vulgaris f. tertia, Chlorella vulgaris  var.  vulgaris f. viridis, Chlorella xanthella, Chlorella zofingiensis, Chlorella trebouxioides, Chlorella vulgaris, Chlorococcum infusionum, Chlorococcum  sp.,  Chlorogonium, Chroomonas  sp.,  Chrysosphaera  sp.,  Cricosphaera  sp.,  Cryptomonas  sp.,  Cyclotella cryptica, Cyclotella meneghiniana, Cyclotella  sp.,  Dunaliella  sp.,  Dunaliella bardawil, Dunaliella bioculata, Dunaliella granulate, Dunaliella maritime, Dunaliella minuta, Dunaliella parva, Dunaliella peircei, Dunaliella primolecta, Dunaliella salina, Dunaliella terricola, Dunaliella tertiolecta, Dunaliella viridis, Dunaliella tertiolecta, Eremosphaera viridis, Eremosphaera  sp.,  Ellipsoidon  sp.,  Euglena, Franceia  sp.,  Fragilaria crotonensis, Fragilaria  sp.,  Gleocapsa  sp.,  Gloeothamnion  sp.,  Hymenomonas  sp.,  Isochrysis aff. galbana, Isochrysis galbana, Lepocinclis, Micractinium, Micractinium  (UTEX LB 2614),  Monoraphidium minutum, Monoraphidium  sp.,  Nannochloris  sp.,  Nannochloropsis salina, Nannochloropsis  sp.,  Navicula acceptata, Navicula biskanterae, Navicula pseudotenelloides, Navicula pelliculosa, Navicula saprophila, Navicula  sp.,  Nephrochloris  sp.,  Nephroselmis  sp.,  Nitschia communis, Nitzschia alexandrine, Nitzschia communis, Nitzschia dissipata, Nitzschia frustulum, Nitzschia hantzschiana, Nitzschia inconspicua, Nitzschia intermedia, Nitzschia microcephala, Nitzschia pusilla, Nitzschia pusilla elliptica, Nitzschia pusilla monoensis, Nitzschia quadrangular, Nitzschia  sp.,  Ochromonas  sp.,  Oocystis parva, Oocystis pusilla, Oocystis  sp.,  Oscillatoria limnetica, Oscillatoria  sp.,  Oscillatoria subbrevis, Pascheria acidophila, Pavlova  sp.,  Phagus, Phormidium, Platymonas  sp.,  Pleurochrysis carterae, Pleurochrysis dentate, Pleurochrysis  sp.,  Prototheca wickerhamii, Prototheca stagnora, Prototheca portoricensis, Prototheca moriformis, Prototheca zopfii, Pyramimonas  sp.,  Pyrobotrys, Sarcinoid chrysophyte, Scenedesmus armatus, Spirogyra, Spirulina platensis, Stichococcus  sp.,  Synechococcus  sp.,  Tetraedron, Tetraselmis  sp.,  Tetraselmis suecica, Thalassiosira weissflogii , and  Viridiella fridericiana.    
     
     
         17 . The composition of  claim 5 , wherein the biomass is derived from a microalgae of a genus selected from the group consisting of  Chlorella, Parachlorella , and  Prototheca.    
     
     
         18 . The composition of  claim 5 , wherein the biomass is derived from an oleaginous microbe genetically engineered to express one of more exogenous genes. 
     
     
         19 . The composition of  claim 5 , wherein the biomass is derived from an oleaginous microbe genetically engineered to express one of more exogenous genes, said microbe producing lipid, wherein the proportions of fatty acids of the lipid are altered relative to that in the lipid produced by an oleaginous microbe lacking said one or more exogenous genes. 
     
     
         20 . A blended fuel comprising a pyrolysis oil produced by the method of  claim 2 , wherein said oleaginous microbe used in the method has been genetically engineered to express one of more exogenous genes that result in said microbe producing lipid in which the proportions of fatty acids are altered relative to the proportions of fatty acids in lipid produced by an oleaginous microbe lacking said one or more exogenous genes.