Abstract: A method is disclosed for the production of alcohol and other bioproducts hemicelluloses extracted from biomass prior to thermal conversion of the biomass to energy. The process can be integrated with the host plant process to minimize the energy loss from extracting hemicelluloses. Also disclosed is a stepwise enzymatic break down of cellulose fibers from a pulping operation which is performed with the redeployment of equipment and vessels contained within typical existing pulp and paper manufacturing mills. The preferred feedstock is highly delignified pulp from acid or alkaline pulping process or from bleaching stage.

Abstract: The disclosure provides a process for producing fluff pulp and ethanol from sugarcane bagasse or straw, comprising: fractionating the feedstock in the presence of an acid catalyst, a solvent for lignin, and water, to generate a solid/liquid slurry comprising cellulose-rich solids, hemicelluloses, and lignin; separating the solid/liquid slurry into a solid stream and a liquid stream; further treating the cellulose-rich solids to produce fluff pulp; hydrolyzing the hemicelluloses to generate hemicellulose monomers; and fermenting at least a portion of the hemicellulose monomers to cellulosic ethanol. Lignin is removed from the process during one or more steps and combusted to provide energy for process requirements. The process is integrated with, and provides energy to, a first-generation process that ferments sugarcane-derived sucrose to first-generation ethanol. Similar processes are possible with energy cane, corn, and other crops.

Abstract: A process is provided for producing a lignin-coated cellulose material, comprising: pre-extracting a lignocellulosic biomass feedstock in the presence of steam or hot water, depositing lignin from the liquid onto a surface of solids to generate a lignin-coated intermediate material; optionally drying the intermediate material; digesting the lignin-coated intermediate material in the presence of an acid, a solvent for lignin, and water, wherein the rate of delignification of surface lignin is lower than the rate of delignification of bulk lignin; and recovering a hydrophobic lignin-coated cellulose material. In some variations, part of the overall process is a combination of Green Power+® and AVAP® technologies. A cellulose-rich composition is provided, containing about 5 wt % to about 15 wt % total lignin, with particles having a higher average surface concentration of lignin compared to an average bulk (internal) concentration of lignin.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity, hydrophobic cellulose. In some variations, the process includes fractionating biomass with an acid (such as sulfur dioxide), a solvent (such as ethanol), and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and depositing lignin onto cellulose fibers to produce lignin-coated cellulose materials (such as dissolving pulp). The crystallinity of the cellulose material may be 80% or higher, translating into good reinforcing properties for composites. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers. These polymers may be combined with the hydrophobic cellulose to form completely renewable composites.

Abstract: A system or plant and method for the production of pure alcohol, acetic acid or its derivatives from the extract containing hemicelluloses filtered after extraction of woody biomass or directly extracted from woody biomass. The process can be integrated with the host plant process to minimize the effect of loss of heat value from the extracted hemicelluloses and reduce the loading to the effluent plant.

Abstract: The disclosure provides a process for separating fermentation inhibitors from a biomass-derived hydrolysate, comprising: introducing a biomass-derived liquid hydrolysate stream to a stripping column; introducing a steam-rich vapor stream to the stripping column to strip fermentation inhibitors (such as acetic acid) from the liquid hydrolysate stream; recovering a stripped liquid stream and a stripper vapor output stream; compressing the stripper vapor output stream; introducing the compressed vapor stream, and a water-rich liquid stream, to an evaporator; recovering, from the evaporator, an evaporated liquid stream and an evaporator output vapor stream; and recycling the evaporator output vapor stream to the stripping column as the steam-rich vapor stream. Other variations utilize a rectification column to recover a rectified liquid stream and a rectification column vapor stream, and recycle the rectification column vapor stream to the stripping column as the steam-rich vapor stream.

Abstract: A biorefinery process to fractionate lignocellulosic materials into cellulose, hemicelluloses and lignin using a pretreatment with mixture of alcohol, sulfur dioxide and water. Further treatment with enzymes, micro-organisms, and optionally bisulfite ion, are used to convert intermediate products to alcohol and lignin derivatives.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with low mechanical energy input. In some variations, the process includes fractionating biomass with lignosulfonic acids, to generate cellulose-rich solids; and mechanically treating the cellulose-rich solids to form nanofibrils and/or nanocrystals. The strong lignosulfonic acids created during delignification give a pH less than 1 and hydrolyze preferentially the amorphous regions of cellulose. The total mechanical energy may be less than 500 kilowatt-hours per ton. The crystallinity of the nanocellulose material may be 80% or higher, translating into good reinforcing properties for composites. The nanocellulose material may include nanofibrillated cellulose, nanocrystalline cellulose, or both. In some embodiments, the nanocellulose material is hydrophobic via deposition of lignin onto the cellulose surface.

Abstract: This invention provides processes and apparatus to convert biomass, including wood and agricultural residues, into low-ash biomass pellets for combustion, alone or in combination with another solid fuel. Some embodiments provide processes for producing low-ash biomass from cellulosic biomass, comprising providing an aqueous extraction solution with acetic acid; extracting the feedstock to produce an extract liquor containing soluble ash, hemicellulosic oligomers, acetic acid, dissolved lignin, and cellulose-rich solids; dewatering and drying the cellulose-rich, lignin-rich solids to produce a low-ash biomass; hydrolyzing the hemicellulosic oligomers to produce hemicellulosic sugars, wherein additional acetic acid is generated; removing a vapor stream comprising vaporized acetic acid from the extract; and recycling the vapor or its condensate to provide some starting acetic acid for the extraction solution. The disclosed processes can produce clean power from biomass.

Abstract: An improved semichemical pulping process is disclosed to reduce washing costs and recovery process costs, while producing equivalent pulp and paper products. In some variations, the invention provides a process for producing a paper product from biomass, comprising: digesting lignocellulosic biomass in the presence of steam and/or hot water to generate an intermediate pulp material and a liquid phase containing extracted hemicelluloses; mechanically refining the intermediate pulp material, to generate a refined pulp material; and introducing the refined pulp material, the liquid phase, and optionally a separate solid material to a paper machine, to produce a paper product. The process optionally employs no washing step. When the liquid phase is washed from the intermediate pulp material or the refined pulp material using an aqueous wash solution, the wash filtrate may be introduced directly or indirectly to the paper machine.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with low mechanical energy input. In some variations, the process includes fractionating biomass with sulfur dioxide or a sulfite compound and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and mechanically treating the cellulose-rich solids to form nanofibrils and/or nanocrystals. The total mechanical energy may be less than 500 kilowatt-hours per ton. The crystallinity of the nanocellulose material may be 80% or higher, translating into good reinforcing properties for composites. The nanocellulose material may include nanofibrillated cellulose, nanocrystalline cellulose, or both. In some embodiments, the nanocellulose material is hydrophobic via deposition of some lignin onto the cellulose surface. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers.

Abstract: In some variations, this invention provides a process for producing fermentable sugars from cellulosic biomass, comprising: extracting biomass with steam or hot water to produce an extract liquor containing hemicellulose oligomers, dissolved lignin, and cellulose-rich solids; separating and washing the cellulose-rich solids; removing a portion of glucan contained in the washed cellulose-rich solids as glucose oligomers using a liquefaction-focused blend of enzymes; co-hydrolyzing glucose oligomers and hemicellulose oligomers, with enzymes or chemical catalyst, to produce glucose and hemicellulose monomers; and recovering the glucose and hemicellulose monomers as fermentable sugars. The liquefaction-focused blend of enzymes contains endoglucanases and exoglucanases. Optionally, the glucose and the hemicellulose monomers may be recovered as separate streams.

Abstract: This invention provides a process for producing biomass pellets and fermentable sugars from cellulosic biomass, comprising: extracting cellulosic biomass feedstock with steam and/or hot water to produce an extract liquor containing hemicellulosic oligomers, dissolved lignin, and cellulose-rich solids, wherein at least some of the steam and/or hot water is derived from an internal or external source of fermentation vinasse; separating at least a portion of the hemicellulosic oligomers from the cellulose-rich solids, to produce intermediate solids; hydrotorrefying the intermediate solids to produce the energy-dense biomass, wherein water for hydrotorrefaction is derived, at least in part, from the internal or external source of fermentation vinasse; pelletizing the energy-dense biomass to form biomass pellets; and hydrolyzing the hemicellulosic oligomers into fermentable sugars. The fermentation vinasse may be recycled from downstream operations involving fermentation of the sugars.

Abstract: The present invention provides a process for fractionating lignocellulosic biomass, comprising: digesting a biomass feedstock in the presence of a solvent for lignin, an acid, and water, to produce cellulose-rich solids; separating and washing the cellulose-rich solids with a wash solvent; washing the cellulose-rich solids with water, to generate washed cellulose-rich solids and a wash liquor comprising fines, wherein the wash liquor is introduced to or in contact with a classifier to remove the fines; and separating the fines and recycling the remaining water. The classifier may include a screen with mesh size in the range of 10 to 500, such as 200. The washed cellulose-rich solids will typically have a lower Kappa number (lignin content) and ash content compared to cellulose-rich solids from a process without a classifier that removes fines.

Abstract: A method for the fractionation of lignocellulosic materials into reactive chemical feedstock in a batch or semi continuous process by the stepwise treatment with aqueous aliphatic alcohols in the presence of sulfur dioxide or acid. Lignocellulosic material is fractionated in a fashion that cellulose is removed as pulp, or converted to esterified cellulose, cooking chemicals are reused, lignin is separated in the forms of reactive native lignin and reactive lignosulfonates and hemicelluloses are converted into fermentable sugars, while fermentation inhibitors are removed. In an integrated vapor compression stripper and evaporator system, aliphatic alcohol is removed from a liquid stream and the resulting stream is concentrated for further processing.

Abstract: In this disclosure, a process for producing biomass pellets and sugars from cellulosic biomass is provided, comprising: extracting the feedstock with steam and/or hot water and optionally with an acid catalyst, to produce cellulose-rich solids and an extract liquor containing hemicellulosic oligomers and lignin; separating the cellulose-rich solids from the extract liquor; filtering the extract liquor to remove at least some of the lignin, thereby generating a filter permeate comprising cleaned extract liquor containing the hemicellulosic oligomers and a filter retentate comprising a lignin-rich stream; hydrolyzing the hemicellulosic oligomers in the cleaned extract liquor with an acid or enzymes, to generate hemicellulosic monomers which are recovered; and pelletizing the cellulose-rich solids to form biomass pellets, wherein the pelletizing utilizes at least some of the lignin-rich stream as a binder or binder component.

Abstract: In some variations, the invention provides a process for fractionating biomass, comprising: in a digestor, fractionating a biomass feedstock in the presence of a solvent for lignin, sulfur dioxide, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; substantially removing the cellulose-rich solids from the liquor; hydrolyzing the hemicellulose contained in the liquor, to produce hemicellulosic monomers; hydrolyzing the cellulose-rich solids to produce glucose; neutralizing, with lime, a hydrolysate liquid containing the hemicellulosic monomers and the glucose, thereby generating gypsum; heating the gypsum to form calcium sulfate; reducing the calcium sulfate with a reductant (such as syngas) to generate calcium oxide and sulfur dioxide; and recycling the calcium oxide and the sulfur dioxide.

Abstract: This invention provides processes to convert biomass into energy-dense biomass for combustion, alone or in combination with another solid fuel. Some embodiments provide processes for producing fermentable sugars and energy-dense biomass from cellulosic biomass, comprising extracting the feedstock with steam and/or hot water to produce an extract liquor containing hemicellulosic oligomers, dissolved lignin, and cellulose-rich solids; separating the extract liquor, to produce dewatered cellulose-rich solids; hydrolyzing the dewatered cellulose-rich solids, thereby removing a portion of the cellulose, to produce intermediate solids (with higher energy density) and a hydrolysate; drying the intermediate solids to produce energy-dense biomass; and recovering fermentable sugars from the hydrolysate. The energy-dense biomass may be pelletized into biomass pellets, which may have a similar energy density as torrefied pellets from wood.

Abstract: Processes are described for fractionating lignocellulosic biomass into cellulose, hemicellulose, and lignin, comprising fractionating lignocellulosic biomass in the presence of a solvent for lignin (such as ethanol), a hydrolysis catalyst (such as sulfur dioxide), and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; hydrolyzing the hemicellulose to produce hemicellulosic monomers; saccharifying the cellulose-rich solids to produce glucose; recovering the hemicellulosic monomers and the glucose, separately or in a combined stream, as fermentable sugars; and fermenting the fermentable sugars to a fermentation product having a higher normal boiling point than water. Process integration of mass and/or energy is disclosed in many specific embodiments. The fermentation product may include an organic acid, an alcohol, a diol, or combinations thereof.

Abstract: A method for the production water insoluble reactive lignin having low sulfur content and lignosulfonates from lignocellulosic material in a batch or continuous process. Lignocellulosic material is fractionated to produce water insoluble native lignin and lignosulfonates in various ratios, while preserving the cellulose and hydrolyzed hemicelluloses using water, ethanol and sulfur dioxide.