A cooking method and a digester system wherein partly digested cellulosic fiber source is compressed during cooking to provide high molecular weight lignin and pulp.

Provided are compositions and processes concerning efficient downstream processing of products derived from organic acids pretreatment of plant materials.

A polymer-nanocellulose-lignin composite as disclosed comprises a polymer, nanocellulose, and lignin, wherein lignin forms a hydrophobic interface between the polymer and the nanocellulose. In some variations, a process is disclosed for producing a polymer-nanocellulose-lignin composite material, comprising: fractionating lignocellulosic biomass in the presence of an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin, wherein lignin deposits onto fiber surfaces or into fiber pores; mechanically treating the cellulose-rich solids to form a hydrophobic nanocellulose material comprising cellulose fibrils and/or cellulose crystals; hydrolyzing the hemicellulose to generate fermentable hemicellulosic sugars; fermenting the fermentable hemicellulosic sugars to generate a monomer or monomer precursor; polymerizing the monomer to produce a polymer; and combining the polymer with the lignin-coated nanocellulose to generate a polymer-nanocellulose-lignin composite material for use in a wide variety of products.

The present invention describes a process for continuous fractionation of CTO (crude tall oil) to RTD (refined tall diesel), said process comprising:—when removing a stream of TOP (tall oil pitch) the CTO is fed through at least two evaporation zones arranged in series so that one stream of CTO is fed from a first evaporation zone to a second evaporation zone, wherein a TOP stream is produced and fed from the second evaporation zone, wherein a first vapor stream is produced within the first evaporation zone and a second vapor stream is produced within the second evaporation zone and wherein there is a temperature difference of at least 10° C. between the first vapor stream and the second vapor stream; and—feeding the first vapor stream and the second vapor stream into a subsequent fractionation column to produce a stream of RTD from the fractionation column, wherein the first vapor stream and the second vapor stream are being fed to different positions, relative to the column height, in the fractionation column, where different conditions are applied to ensure suitable fractionations of a more fatty acid rich material and a more rosin rich material, respectively, and which different positions in the fractionation column are separated by packing means.

The present invention relates to fractionation of crude tall oil, which originates from the Kraft process black liquor. In the method, according to the present invention, simulated moving bed (SMB) chromatography is used to efficiently separate fractions from the crude tall oil.

The present invention relates to a method for producing one or more low molecular weight aromatic lignin-derived compounds. The method preferably comprises providing lignocellulosic material, subjecting the lignocellulosic material to a pulping process, separating pulp to provide a substantially pulp-free process stream comprising a modified lignin-derived component, isolating the modified lignin-derived component, subjecting the isolated modified lignin-derived component to a decomposition step comprising oxidative cracking (cracking and oxidizing) or reducing under the influence of a catalyst or electro-oxidation, and subjecting the resulting products to an isolation step, to provide a low molecular weight aromatic lignin-derived compound. Said compound may be further modified, e.g. by annulation. The inventive method preferably comprises further oxidizing said compound to a redox active compound. Additionally, the present invention relates to compounds obtainable by the inventive method and to an assembly for carrying out the inventive method. Furthermore, the present invention refers to a method for providing an existing pulp and/or paper manufacturing plant with said assembly.

An improved continuous process for production of cellulose from glass-like feedstock, which includes: (i) cooking of comminuted grass-like feedstock in white liquor which contains 0.5-2.0% w/w NaOH and 0.5-25.0% w/w NaCl at 95-100° C.; (ii) bleaching process of the brown cellulose in the white liquor of the same composition with oxygen (O.sub.2) and chlorine (Cl.sub.2) at 70-100° C., yielding bleached cellulose pulp; where, (iii) lignin and other side-products are separated by continuous electrolysis, where the white liquor is regenerated, together with O.sub.2 and Cl.sub.2 for the bleaching purpose, thereby closing the cycle of the process.

It is disclosed a process for producing a bio-product from a ligno-cellulosic biomass, wherein the ligno-cellulosic biomass, a gas and steam are introduced in a pressurized reactor operated in a continuous manner at conditions to have a vapor head space. In the pressurized reactor, the vapor head space is maintained at a vapor head space temperature and at a pressure which is at least 1 bar greater than a pure steam equilibrium pressure at the vapor head space temperature. The ligno-cellulosic biomass is then refined by rapidly releasing the pressure while discharging the ligno-cellulosic biomass from the pressurized reactor assembly to create a pre-treated ligno-cellulosic biomass, which is then hydrolyzed and converted to the bio-product. Preferably, at least a portion of the gas is air entrapped in the ligno-cellulosic biomass and it is introduced into the pressurized reactor as part of the ligno-cellulosic biomass. In a preferred embodiment, the lignocellulosic biomass is subjected to a soaking step and an aeration step prior to being introduced into the pressurized reactor, without any xylans separation step.

The invention relates to a method for producing lignin particles, comprising the steps of: a) extracting lignin from a lignincontaining starter material, using a mixture that comprises at least one organic solvent and water, and b) precipitating the lignin in the solution from step a).

The invention relates to a method for clarification of raw green liquor in a sedimentation tank. According to the invention is a part of dregs separated in the sedimentation tank recirculated back into the inflow of raw green liquor, and preferably after passing the dregs through at least one turbulence generator (30, 31) that could break up larger dregs particles into smaller dregs particles, and thus create larger total surface on the dregs particles, improving sedimentation rate in the sedimentation tank. In a preferred embodiment is the recirculated dregs added into the flow of raw green liquor before a flocculant is added into the flow of raw green liquor and mixed recirculated dregs.