927 results about "Lignocellulosic biomass" patented technology

A method wherein lignocellulosic biomass materials are converted into combustible fuel products. In particular, the method is a continuous process, involving wet oxidation or steam explosion, for fermentatively converting such biomass materials into ethanol using a process design that permits all or part of the process water from the ethanol fermentation process to be recycled to reduce the consumption of process water. The effluent from the ethanol fermentation step may be subjected to an anaerobic fermentation step generating methane and a water effluent in which the amount of potentially inhibitory substances is at a sub-inhibitory level, which in turn permits all or part of the effluent water from the anaerobic fermentation step to be recycled into the process.

A continuous and modular process converts lignocellulosic materials for the production of ethanol principally and / or chemicals such as methanol, butanediol, propanediol, hydrocarbon fuel, etc. Renewable lignocellulosic biomass such as but not all inclusive hardwoods (gum, beech, oak, sweet gum, poplar, eucalyptus, etc.), soft woods (pines, firs, spruce, etc.), corn stovers, straws, grasses, recycled papers, waste products from pulp and paper mills, etc can be used as feedstock. The process is designed to be modular and the feed entry point can be selected to adapt to different biomass feedstock. Lignocellulosic biomass such as hardwood and softwood are subjected to chemical / pressure treatment stages using potent and selective chemicals such as sodium chlorite / acetic acid (anhydrous) and chlorine / chlorine dioxide to separate the main components—lignin, cellulose (glucose) and hemicelluloses (xylose, arabinose, galactose)—into three process streams. The separated carbohydrates are further subjected to washing, cleaning, neutralization, and / or mild hydrolysis and subsequently fermented to produce ethanol. Residual lignin and extractives remained with the cellulose are removed by chemical treatment steps to enhance the fermentations of cellulose. Pre-hydrolysate after neutralization to neutralize and remove toxic components such as acetic acid, furfural, phenolics, etc. containing (xylose, arabinose, galactose) and hexoses (glucose) can be either separately or together with the purified cellulosic fraction fermented to produce ethanol. Approximately 100 gallons of ethanol, suitable to be used as a fuel, can be produced from one dried ton of wood. Significant amount of lignin are separated as a by-product and can be converted to hydrocarbon fuel, surfactant, drilling aid, or can be incinerated for generation of power and steam.

This invention provides novel enzyme compositions using newly identified and isolated C. lucknowense enzymes, including CBH Ib CBH IIb, EG II, EG VI, β-glucosidase, and xylanase II in conjunction with previously identified enzymes CBH Ia, CBH IIa (previously described as Endo 43), and EG V. These enzyme compositions demonstrate an extremely high ability to convert lignocellulosic biomass (e.g., Avicel, cotton, Douglas fir wood pretreated by organosolv) to glucose. CBH Ia and IIb, which both have a cellulose-binding module (CBM) displayed a pronounced synergism with three major endoglucanases (EG II, EG V, EG VI) from the same fungus in hydrolysis of cotton as well as a strong synergy with each other. The enzyme compositions are effective in hydrolysis of the lignocellulosic biomass.

In a process for converting lingnocellulosic biomass to ethanol, the improvement of obtaining higher fermentable soluble sugar yields by drying acid impregnated biomass particles, comprising: a) feeding moist lignocellulosic biomass into an acid impregnator to render it acid-soaked and draining the acid-soaked biomass to about 30% to 35% by weight solids; b) dewatering the acid-soaked biomass by drying or centrifugation to prevent compaction of the biomass and arrive at about 40% to 60% by weight solids; c) subjecting the acid-impregnated biomass to a first-stage hydrolysis reactor at a temperature of from 130° C. to 220° C. and discharging formed hydrolysate into a flash tank at about 120° C. to 140° C. to hydrolyze most of the remaining soluble oligosaccharides to monomeric sugars, and flashing remaining hydrolysate to a second flash tank at a lower temperature than the first flash tank-the second flash tank serving as a feed surge tank for a counter-current extractor; d) washing the hydrolysate, adjusting the pH of the sugar extract to about 5, and recovering more than 95% of the soluble sugars in the first-stage hydrolysate slurry by a counter-current extractor; e) subjecting remaining washed-first stage solids of pretreated biomass to a second-stage acid and metal salt impregnator and dewatering by drying or centrifugation to prevent compaction of biomass to arrive at 40% to 60% by weight solids; f) subjecting the acid and metal salt-impregnated biomass to a second-stage hydrolysis reactor at a temperature from 190° C. to 240° C. and discharging formed hydrolysate into a flash tank, at about 120° C. to 140° C. to hydrolyze most of the remaining soluble oligosaccharides to monomeric sugars and flashing remaining hydrolysate to a second flash tank at a lower temperature than the first flash tank, the second flash tank serving as a feed surge tank for second-stage fementors; g) cooling pH-adjusted extract from the counter-current extractor, feeding the extract to a first-stage fermentor and air sparging the first-stage fermentor at a rate sufficient to promote enough yeast growth to compensate for loss through second-stage fermentors; h) pH adjusting second-stage hydrolysate slurry to 4.5, cooling the slurry and adding it into the top of the first fermentor of a two-fermentor train in the second stage fermentors, pumping broth from the bottom of the first stage fermentors to the second stage fermentors while the yeast is in the growth phase for a period sufficient to consume over 95% of fermentable sugars; and i) recovering ethanol.

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.

Countercurrent extraction of lignocellulosic biomass such as trees, grasses, shrubs, and agricultural residues or waste involves the separation of cellulose fibers from other constituents, for subsequent use in the manufacture of paper, plastics, ethanol, and other industrial chemicals. Systems and methods involve continuous, multiple processing steps that may include chemical reactions with mixing at elevated temperature and / or pressure, efficient reagent or solvent utilization, filtration at elevated temperature and / or pressure, controlled discharge of liquid and solid products, and energy recuperation.

The present invention generally relates to processes for production of ethanol from cellulosic biomass. The present invention also relates to production of various co-products of preparation of ethanol from cellulosic biomass. The present invention further relates to improvements in one or more aspects of preparation of ethanol from cellulosic biomass including, for example, improved methods for cleaning biomass feedstocks, improved acid impregnation, and improved steam treatment, or “steam explosion.”

A method for preparing biomass for slurry processing. The method includes solubilizing the solid material into either a dissolved state or a suspended solid in a liquid phase, and treating the liquid phase to produce chemicals and fuels.

A method for converting a carbohydrate to a furan in a polar aprotic solvent in the presence of a chloride, bromide, or iodide salt or a mixture thereof and optionally in the presence of an acid catalyst, a metal halide catalyst and / or an ionic liquid (up to 40 wt %). The method can be employed in particular to produce furfural or 5-hydroxymethylfurfural.

A process for obtaining a product sugar stream from cellulosic biomass is disclosed. In one process, the cellulosic biomass is pretreated at a pH between about 0.4 to 2.0 by adding one or more than one acid to produce a pretreated cellulosic biomass comprising acetic acid. One or more than one base is then added to the pretreated cellulosic biomass to adjust the pretreated cellulosic biomass to a pH of about 4.0 to about 6.0 to produce a neutralized cellulosic biomass comprising inorganic salt and acetate salt. The neutralized biomass is then hydrolyzed by cellulase enzymes to produce a crude sugar stream. Insoluble residue is separated from the crude sugar stream and the resulting clarified sugar stream is treated using ion exclusion chromatography at about pH 5.0 to about 10.0 to produce one or more raffinate streams and a product stream. The raffinate stream comprises inorganic salts and acetate salts, and the product stream comprises sugar. The product stream may then be fermented or otherwise further processed. In an alternate process, a product sugar stream is obtained from a crude sugar stream that is produced from conversion of cellulosic biomass to sugar. The cellulosic biomass may be produced using any suitable method. In this process the crude sugar stream is treated using ion exclusion chromatography at about pH 5.0 to about 10.0 to produce one or more than one raffinate stream comprising sulfate and acetate salts, and a product stream comprising sugar, and the product sugar stream is obtained.