Abstract: This invention provides optimized fermentation of cellulosic and hemicellulosic sugars. Biomass-derived hemicellulosic and cellulosic sugars are independently conditioned and separately fermented, utilizing reuse and recycle of microorganisms, metabolic intermediates, and nutrients. Conditioned sugars can be fermented in separate vessels, where excess cells from glucose fermentation are conveyed to hemicellulose sugar fermentation along with raffinate from solvent recovery, to enhance productivity and product yield.

Abstract: A composition comprising nanocellulose is disclosed, wherein the nanocellulose contains very low or essentially no sulfur content. The nanocellulose may be in the form of cellulose nanocrystals, cellulose nanofibrils, or both. The nanocellulose is characterized by a crystallinity of at least 80%, an onset of thermal decomposition of 300° F. or higher, and a low light transmittance over the range 400-700 nm. Other variations provide a composition comprising lignin-coated hydrophobic nanocellulose, wherein the nanocellulose contains very low or essentially no sulfur content. Some variations provide a composition comprising nanocellulose, wherein the nanocellulose contains about 0.1 wt % equivalent sulfur content, or less, as SO4 groups chemically or physically bound to the nanocellulose. In some embodiments, the nanocellulose contains essentially no hydrogen atoms (apart from hydrogen structurally contained in nanocellulose itself) bound to the nanocellulose.

Abstract: Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with surprisingly low mechanical energy input. 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 mechanically treating the cellulose-rich solids to form nanofibrils and/or nanocrystals. 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: The invention provides a continuous process for enzymatic hydrolysis of pretreated biomass, the process comprising: providing a pretreated lignocellulosic biomass feed material containing cellulose; introducing the pretreated lignocellulosic biomass feed material to a mechanical-treatment unit containing one or more decompression regions configured to release pressure; introducing a liquid solution containing cellulase enzymes to one or more decompression regions in the mechanical-treatment unit, wherein the liquid solution enters void spaces between fibers of the pretreated lignocellulosic biomass feed material, to form enzyme-containing cellulose-rich solids; and retaining the enzyme-containing cellulose-rich solids under effective hydrolysis conditions to hydrolyze at least some of the cellulose to glucose. Various apparatus configurations are disclosed for the mechanical-treatment unit.

Abstract: In some variations, a process is provided for producing a pulp product at a biorefinery site, comprising: converting a woody cellulosic material to a first pulp stream; converting a non-woody cellulosic material to a second pulp stream; blending the second pulp stream into the first pulp stream; and recovering or further processing the blended pulp stream as a pulp product. Biorefinery site infrastructure may be shared between the woody and non-woody lines. Also, the process may include process integration of mass and/or energy between the woody and non-woody lines. The process may be a retrofit addition to a pulp plant, or a greenfield biorefinery site. The non-woody line also can generate fermentable sugars, for fermentation to ethanol (or other products). Through allocation of carbon credits from the ethanol to the pulp, the final pulp product life-cycle profile can be improved.

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: The present invention provides a process for fractionating lignocellulosic biomass, comprising: contacting biomass with SO2, water, and optionally a first solvent, to produce intermediate solids; then contacting the intermediate solids with SO2, water, and a second solvent, to produce cellulose-rich solids and a liquid phase comprising hemicelluloses and lignin. The first concentration of SO2 may be lower or higher than the second concentration of SO2. It is desirable to vary the SO2 and solvent concentrations in different stages to optimize the removal of hemicellulose versus lignin. The resulting cellulose-rich material can contain very low hemicellulose, very low lignin, or both low hemicellulose and low lignin. High-purity cellulose is useful both for producing glucose as well as for cellulose products or derivatives. The hemicelluloses may be hydrolyzed to produce monomeric sugars, and the lignin may be recovered as a co-product.

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: The GreenBox+ technology is suitable to extract hemicellulose sugars prior to pulping of biomass into pulp products. The revenue obtainable from the sugar stream can significantly improve the economics of a pulp and paper mill. An initial extraction and recovery of sugars is followed by production of a pulp product with similar or better properties. Other co-products such as acetates and furfural are also possible. Some variations provide a process for co-producing pulp and hemicellulosic sugars from biomass, comprising: digesting the biomass in the presence of steam and/or hot water to extract hemicellulose into a liquid phase; washing the extracted solids, thereby generating a liquid wash filtrate and washed solids; separating the liquid wash filtrate from the washed solids; refining the washed solids at a refining pH of about 4 or higher, thereby generating pulp; and hydrolyzing the hemicellulose to generate hemicellulosic fermentable sugars.

Abstract: A composition comprising nanocellulose is disclosed, wherein the nanocellulose contains very low or essentially no sulfur content. The nanocellulose may be in the form of cellulose nanocrystals, cellulose nanofibrils, or both. The nanocellulose is characterized by a crystallinity of at least 80%, an onset of thermal decomposition of 300° F. or higher, and a low light transmittance over the range 400-700 nm. Other variations provide a composition comprising lignin-coated hydrophobic nanocellulose, wherein the nanocellulose contains very low or essentially no sulfur content. Some variations provide a composition comprising nanocellulose, wherein the nanocellulose contains about 0.1 wt % equivalent sulfur content, or less, as SO4 groups chemically or physically bound to the nanocellulose. In some embodiments, the nanocellulose contains essentially no hydrogen atoms (apart from hydrogen structurally contained in nanocellulose itself) bound to the nanocellulose.

Abstract: Conventionally, sugarcane processing avoids leaving residual sucrose in the bagasse, since the bagasse will be burned and the value of the sucrose would be lost. However, when coupled with a Green Power+® process to extract hemicelluloses, sucrose may also be extracted and recovered from the bagasse. In some variations, a process includes mechanically treating a feedstock to generate a sucrose-rich stream and lignocellulosic material that intentionally retains a significant amount of the initial sucrose in the feedstock; extracting the lignocellulosic material with steam and/or hot water to produce cellulose-rich solids and an extract liquor containing hemicellulosic oligomers and sucrose; and then hydrolyzing the hemicellulosic oligomers into a hemicellulose sugar stream. Each of the sucrose-rich stream and the hemicellulose sugar stream (containing the starting residual sucrose) may be recovered or further processed (e.g., fermented to ethanol).

Abstract: A method 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: A continuous process for producing hemicellulose sugars from a biomass extraction liquor is provided. A system is configured for continuously producing hemicellulose sugars and/or hemicellulose derivatives from a biomass extraction liquor, the system comprising at least a first hydrolysis reactor and a second hydrolysis reactor. Each of the hydrolysis reactors is in switchable communication with (i) an operating feed stream of a biomass extraction liquor containing water, hemicellulose oligomers, and dissolved or suspended lignin, and (ii) a cleaning feed stream of a cleaning agent selected from the group consisting of steam, an alkaline solution, an organic solvent, and combinations thereof. The cleaning agent dissolves precipitated lignin formed from the lignin under the hydrolysis reaction conditions.

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: The GreenBox+ technology is suitable to extract hemicellulose sugars prior to pulping of biomass into pulp products. The revenue obtainable from the sugar stream can significantly improve the economics of a pulp and paper mill. An initial extraction and recovery of sugars is followed by production of a pulp product with similar or better properties. Other co-products such as acetates and furfural are also possible. Some variations provide a process for co-producing pulp and hemicellulosic sugars from biomass, comprising: digesting the biomass in the presence of steam and/or hot water to extract hemicellulose into a liquid phase; washing the extracted solids, thereby generating a liquid wash filtrate and washed solids; separating the liquid wash filtrate from the washed solids; refining the washed solids at a refining pH of about 4 or higher, thereby generating pulp; and hydrolyzing the hemicellulose to generate hemicellulosic fermentable sugars.

Abstract: The present invention generally provides methods of improving lignin separation during biomass fractionation with an acid to release sugars and a solvent for lignin (such as ethanol). In some embodiments, a digestor is employed to fractionating a feedstock in the presence of a solvent for lignin, sulfur dioxide, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin. A solid additive is added to the digestor, wherein the solid additive combines with at least a portion of the lignin. Then a mixture of lignin and the solid additive is separated from the liquor, prior to hemicellulose recovery. Optionally, a solid additive may also be introduced to a hydrolysis reactor for converting hemicellulose oligomers to monomers, to improve separation of acid-catalyzed lignin. In some embodiments, the solid additive is gypsum or a gypsum/lignin mixture.

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: Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with surprisingly low mechanical energy input. 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 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.

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: The present invention provides a method of treating a fermentation stream to remove dissolved gases, comprising obtaining a fermentation stream including water, one or more fermentation products, and dissolved gases; continuously sonicating the fermentation stream to generate acoustically cavitated gases from the dissolved gases; and applying vacuum to release the acoustically cavitated gases from the fermentation stream. The dissolved gases may include air, oxygen, nitrogen, helium, argon, carbon dioxide, carbon monoxide, hydrogen, or other non-condensables. The release of acoustically cavitated gases may optionally be done simultaneously with sonication. At least 75%, such as up to 95% or more, of the dissolved gases may be released from the fermentation stream. The disclosed method positively impacts downstream operations and product quality by removing dissolved gases.