Patent application number | Description | Published |
20100159552 | PROCESS FOR ALCOHOLIC FERMENTATION OF LIGNOCELLULOSIC BIOMASS - A process for the production of ethanol wherein a hydrolyzed lignocellulosic biomass is fermented in the presence of a stillage residue. The fermentation of cellulosic hydrolysates is improved by adding prior to and/or during fermentation a stillage residue side stream from a corn starch-to-ethanol process as a nutrient source for the yeast organisms used in the fermentation. Stillage residues from the grain dry mill ethanol producing process, including the whole stillage, wet cake, thin stillage, and/or syrup are added to assist as a nitrogen and nutrient source for the fermentive processes. The stillage residue is produced by any grain-to-ethanol process. | 06-24-2010 |
20100263814 | PRETREATMENT OF LIGNOCELLULOSIC BIOMASS THROUGH REMOVAL OF INHIBITORY COMPOUNDS - A process for the pretreatment of lignocellulosic biomass is disclosed. The process is intended for use in connection with biomass to ethanol processes and is directed in particular to an economical removal of inhibitory compounds generated in biomass pretreatment, which are inhibitory to downstream hydrolysis and fermentation steps. The process includes the steps of heating the lignocellulosic biomass with steam to a preselected temperature, at a preselected pressure and for a preselected time to hydrolyze and solubilize hemicelluloses in the biomass; explosively decomposing the biomass into fibers; and extracting from the resulting reaction mixture a liquefied portion of the lignocellulosic biomass before or after explosive decomposition. The liquefied portion is extracted to remove compounds from the lignocellulosic biomass which are inhibitory to enzymatic cellulose hydrolysis and sugar fermentation to ethanol. For improved efficiency and economy, the inhibitory compounds are not completely removed. Furthermore, xylose has been found to be a good indicator compound for the general level of inhibitory compounds in the reaction mixture and the extraction step is therefore controlled on the basis of the xylose content in the reaction mixture. In particular, the extracting step is discontinued once a dry matter (dm) content of xylose, as monomer or oligomer, in the reaction mixture of 4% to 8% (w/w dm) is achieved. This most economically balances the practical need for inhibitory compound removal with the economical need to control and preferably minimize the costs of the overall ethanol production process. | 10-21-2010 |
20100269990 | SEPARATION OF REACTIVE CELLULOSE FROM LIGNOCELLULOSIC BIOMASS WITH HIGH LIGNIN CONTENT - A process for separating the components of lignocellulosic biomass for the purpose of producing a pure reactive cellulose is disclosed. The process has two stages. In the first stage, the lignocellulosic biomass is pretreated with steam, with or without an acid catalyst, and then pressed, with or without the presence of an eluent, to remove hemicellulose and other impurities. In the second stage, the pretreated biomass is extracted with a solvent such as ethanol with or without acid catalysts in order to remove lignin and release a purified cellulose stream. The extracted cellulose is then rapidly decompressed to rupture the fibrous structure. The process provides a purified cellulose stream that is relatively easy to hydrolyze with enzymes and ferment to biofuels and other chemicals such as ethanol. | 10-28-2010 |
20100313882 | FRACTIONATION OF BIOMASS FOR CELLULOSIC ETHANOL AND CHEMICAL PRODUCTION - A process is defined for the continuous steam pretreatment and fractionation of corn cobs and low lignin lignocellulosic biomass to produce a concentrated cellulose solid stream that is sensitive to enzymatic hydrolysis. Valuable chemicals are recovered by fractionating the liquid and vapor stream composed of hydrolysis and degradation products of the hemicellulose. Cellulosic derived glucose is produced for fermentation to biofuels. A hemicellulose concentrate is recovered that can be converted to value added products including ethanol. | 12-16-2010 |
20120329116 | PRETREATMENT OF LIGNOCELLULOSIC BIOMASS THROUGH REMOVAL OF INHIBITORY COMPOUNDS - A process for the pretreatment of lignocellulosic biomass is disclosed, which includes the steps of pretreating the lignocellulosic biomass to hydrolyze and solubilize hemicelluloses in the biomass; explosively decomposing the biomass into fibers; and extracting from the resulting solids fraction a liquefied portion of the lignocellulosic biomass before or after explosive decomposition. This removes compounds from the lignocellulosic biomass which are inhibitory to enzymatic cellulose hydrolysis and sugar fermentation to ethanol. For improved economy, the inhibitory compounds are not completely removed. The extraction step is controlled on the basis of the xylose equivalent content in the reaction mixture and the extracting step is discontinued once a xylose equivalent content of 4-8% w/w of xylose in the dry matter of the solids fraction is achieved. This most economically balances the practical need for inhibitory compound removal with the economical need to minimize the costs of the overall ethanol production process. | 12-27-2012 |
20130014749 | CONDITIONING OF BIOMASS FOR IMPROVED C5/C6 SUGAR RELEASE PRIOR TO FERMENTATION - Disclosed is an improvement in a conventional process for C5 and C6 sugar recovery from lignocellulosic biomass for fermentation to ethanol, which process including the conventional steps of pretreatment of the biomass with steam at elevated temperature and pressure, collection of C5 sugars from hemicellulose breakdown, cellulose hydrolysis and collection of C6 sugars from cellulose breakdown. The improvement includes conditioning of the biomass prior to the pretreatment step by heating the biomass with steam for a time period between 5 minutes to 60 minutes to achieve a steam treated biomass having a temperature of about 80 to 100°C.; and adjusting a moisture content of the steam treated biomass to about 45% to 80%. An increased recovery of C5 and C6 sugars is achieved compared to the conventional process. | 01-17-2013 |
20130017589 | FRACTIONATION OF LIGNOCELLULOSIC BIOMASS FOR CELLULOSIC ETHANOL AND CHEMICAL PRODUCTION - A process is defined for the continuous steam pretreatment and fractionation of corn cobs and low lignin lignocellulosic biomass to produce a concentrated cellulose solid stream that is sensitive to enzymatic hydrolysis. Valuable chemicals are recovered by fractionating the liquid and vapor stream composed of hydrolysis and degradation products of the hemicellulose. Cellulosic derived glucose is produced for fermentation to biofuels. A hemicellulose concentrate is recovered that can be converted to value added products including ethanol. | 01-17-2013 |
20130029406 | TWO STAGE CONTINUOUS PRE-TREATMENT OF LIGNOCELLULOSIC BIOMASS - Disclosed is a method of pretreating biomass in two pretreatment stages as part of a biofuel production process. The first stage pretreatment is carried out by heating the biomass to a first stage temperature of 140° C. to 180° C. for a first stage time of 30 minutes to 2 hours at a first stage pressure of 105 to 150 psig; and the second stage is carried out by heating the biomass to a second stage temperature of 190° C. to 210° C. for a second stage time of 2 to 10 minutes at a second stage pressure of 167 to 262 psig. The biomass may be initially conditioned prior to the first pretreatment stage by atmospheric steam heating and adjusting the moisture content of the biomass. Hemicellulose and inhibitors (inhibitory compounds) to downstream hydrolysis and fermentation are preferably removed between the first and second pretreating stages, more preferably after each pretreatment stage. | 01-31-2013 |
Patent application number | Description | Published |
20100159552 | PROCESS FOR ALCOHOLIC FERMENTATION OF LIGNOCELLULOSIC BIOMASS - A process for the production of ethanol wherein a hydrolyzed lignocellulosic biomass is fermented in the presence of a stillage residue. The fermentation of cellulosic hydrolysates is improved by adding prior to and/or during fermentation a stillage residue side stream from a corn starch-to-ethanol process as a nutrient source for the yeast organisms used in the fermentation. Stillage residues from the grain dry mill ethanol producing process, including the whole stillage, wet cake, thin stillage, and/or syrup are added to assist as a nitrogen and nutrient source for the fermentive processes. The stillage residue is produced by any grain-to-ethanol process. | 06-24-2010 |
20100263814 | PRETREATMENT OF LIGNOCELLULOSIC BIOMASS THROUGH REMOVAL OF INHIBITORY COMPOUNDS - A process for the pretreatment of lignocellulosic biomass is disclosed. The process is intended for use in connection with biomass to ethanol processes and is directed in particular to an economical removal of inhibitory compounds generated in biomass pretreatment, which are inhibitory to downstream hydrolysis and fermentation steps. The process includes the steps of heating the lignocellulosic biomass with steam to a preselected temperature, at a preselected pressure and for a preselected time to hydrolyze and solubilize hemicelluloses in the biomass; explosively decomposing the biomass into fibers; and extracting from the resulting reaction mixture a liquefied portion of the lignocellulosic biomass before or after explosive decomposition. The liquefied portion is extracted to remove compounds from the lignocellulosic biomass which are inhibitory to enzymatic cellulose hydrolysis and sugar fermentation to ethanol. For improved efficiency and economy, the inhibitory compounds are not completely removed. Furthermore, xylose has been found to be a good indicator compound for the general level of inhibitory compounds in the reaction mixture and the extraction step is therefore controlled on the basis of the xylose content in the reaction mixture. In particular, the extracting step is discontinued once a dry matter (dm) content of xylose, as monomer or oligomer, in the reaction mixture of 4% to 8% (w/w dm) is achieved. This most economically balances the practical need for inhibitory compound removal with the economical need to control and preferably minimize the costs of the overall ethanol production process. | 10-21-2010 |
20100269990 | SEPARATION OF REACTIVE CELLULOSE FROM LIGNOCELLULOSIC BIOMASS WITH HIGH LIGNIN CONTENT - A process for separating the components of lignocellulosic biomass for the purpose of producing a pure reactive cellulose is disclosed. The process has two stages. In the first stage, the lignocellulosic biomass is pretreated with steam, with or without an acid catalyst, and then pressed, with or without the presence of an eluent, to remove hemicellulose and other impurities. In the second stage, the pretreated biomass is extracted with a solvent such as ethanol with or without acid catalysts in order to remove lignin and release a purified cellulose stream. The extracted cellulose is then rapidly decompressed to rupture the fibrous structure. The process provides a purified cellulose stream that is relatively easy to hydrolyze with enzymes and ferment to biofuels and other chemicals such as ethanol. | 10-28-2010 |
20120111514 | BAGASSE FRACTIONATION FOR CELLULOSIC ETHANOL AND CHEMICAL PRODUCTION - A process is defined for the continuous steam pretreatment and fractionation of bagasse to produce a concentrated cellulose solid stream that is sensitive to enzymatic hydrolysis. Valuable chemicals are recovered by fractionating the liquid and vapor stream composed of hydrolysis and degradation products of the hemicellulose. Cellulosic derived glucose is produced for fermentation to biofuels. A hemicellulose concentrate is recovered that can be converted to value added products including ethanol. | 05-10-2012 |
20120115200 | CONTINUOUS PROCESS FOR THE PRODUCTION OF ETHANOL FROM LIGNOCELLULOSIC BIOMASS - A continuous process for the recovery of ethanol from hemicellulose and cellulose from lignocellulosic biomass. Yield of fermentable sugars can be maximized by continuous operation of the pre-treatment system and careful selection of pretreatment conditions including the addition of only small amounts of dilute mineral acid and low pressure. With this approach, the xylose component that is mainly present in its unfermentable oligomeric form in known pre-hydrolysis Kraft processes can be recovered more efficiently and as a monomer that can be fermented by xylose fermenting yeasts and bacteria. Due to the use of only dilute acids, there is a very low loss of glucose and xylose hence very low production of toxic chemicals (e.g. HMF, furfural) in the pretreatment step. The resulting overall fermentation efficiency of both hexose and pentose sugars is 90% of the theoretical maximum. | 05-10-2012 |