| GREENFIELD ETHANOL INC. Patent applications |
| Patent application number | Title | Published |
| 20120118517 | SOLID/FLUID SEPARATION DEVICE AND METHOD FOR TREATING BIOMASS INCLUDING SOLID/FLUID SEPARATION - A solid/fluid separation module and pretreatment apparatus and method enables pretreatment of biomass at high temperature and pressure with the ability to vary residence and processing times. | 05-17-2012 |
| 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 |
| 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 |
| 20110229949 | GENETICALLY MODIFIED YEAST STRAIN - A polyploid transformed yeast cell comprising a deleted or disrupted GDH1 gene encoding an NADPH-dependent glutamate dehydrogenase. The polyploid yeast cell shows increased production of ethanol and reduced production of glycerol when compared with a control polyploid yeast cell. | 09-22-2011 |
| 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 |
| 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 |
| 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 |
| 20100255554 | FED BATCH PROCESS FOR BIOCHEMICAL CONVERSION OF LIGNOCELLULOSIC BIOMASS TO ETHANOL - A method for optimization of a fed batch hydrolysis process wherein the hydrolysis time is minimized by controlling the feed addition volume and/or batch addition frequency of the prehydrolysate and optionally also the enzyme feed. The increase over time in hydrolysate consistency and volume and/or concentration of sugars released in the reactor, so that the enzymatic hydrolysis is controlled, significantly reduces the impact of cellulase feedback inhibition, especially for enzyme contents lower than 0.5%. The overall time to reach conversion of the total prehydrolysate feed is reduced significantly where the batch addition frequency is equal to one batch each time 70% to 90%, preferably 80%, conversion of the previous batch is reached in the reaction mixture. At an enzyme load of 0.3% in the reaction mixture, the optimum frequency each time 80% conversion was reached was found to be one batch every 105 minutes. | 10-07-2010 |
| 20100181034 | REMOVAL OF INHIBITORY COMPOUNDS DURING PRE-TREATMENT OF LIGNOCELLULOSIC BIOMASS - A process for the pretreatment of lignocellulosic biomass, in particular during the production of ethanol from biomass. The process including a cooking step where the biomass is exposed to steam at elevated temperatures and pressures for a preselected period of time in a treatment vessel. During the process, volatile and liquid compounds are purged from the treatment vessel. | 07-22-2010 |
| 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 |
| 20090239276 | GENETICALLY MODIFIED YEAST STRAIN - A polyploid transformed yeast cell comprising a deleted or disrupted GDH1 gene encoding an NADPH-dependent glutamate dehydrogenase, said polyploid yeast cell showing increased production of ethanol and reduced production of glycerol when compared with a control polyploid yeast cell. | 09-24-2009 |