The present invention relates a process and a system for the point-of-use dilution of microfibrillated cellulose (MFC) from a higher solids content to a lower solids content, for example from a solids content in the range of 5% weight by weight (w/w)-50% w/w, preferably 5% w/w-30% w/w, further preferably 5% w/w-15% w/w, down to a solids content of below 7% w/w, preferably below 5% w/w, preferably to a solids content of 0.01% w/w-5% w/w, further preferably to a solids content of 0.1% w/w-3% w/w. The process at least comprises the following steps: (i) providing microfibrillated cellulose in a solvent, wherein the solids content is in the range of 5% weight by weight (w/w)-50% w/w, preferably 5% w/w-30% w/w, further preferably 5 w/w-15% w/w; (ii) subjecting said microfibrillated cellulose from step (i) to a dilution step in a rotor-stator mixer; (iii) simultaneously to step (ii): injecting solvent into the rotor-stator mixer, or into a volume segment upstream of the rotor-stator mixer, in order to lower the solids content of the microfibrillated cellulose in the rotor-stator mixer.

The present invention relates a process and a system for the point-of-use dilution of microfibrillated cellulose (MFC) from a higher solids content to a lower solids content, for example from a solids content in the range of 5% weight by weight (w/w)-50% w/w, preferably 5% w/w-30% w/w, further preferably 5% w/w-15% w/w, down to a solids content of below 7% w/w, preferably below 5% w/w, preferably to a solids content of 0.01% w/w-5% w/w, further preferably to a solids content of 0.1% w/w-3% w/w. The process at least comprises the following steps: (i) providing microfibrillated cellulose in a solvent, wherein the solids content is in the range of 5% weight by weight (w/w)-50% w/w, preferably 5% w/w-30% w/w, further preferably 5 w/w-15% w/w; (ii) subjecting said microfibrillated cellulose from step (i) to a dilution step in a rotor-stator mixer; (iii) simultaneously to step (ii): injecting solvent into the rotor-stator mixer, or into a volume segment upstream of the rotor-stator mixer, in order to lower the solids content of the microfibrillated cellulose in the rotor-stator mixer.

A process is provided for preparing a low density, fibrous primary lignocellulose biomass, particularly straw for anaerobic digestion at large scale, i.e. >2 MW.sub.th, which comprises a step that greatly increasing the density of the straw through size reduction, moisture adjustment and compression ahead of loading and subsequent agitation of the resultant biomass in a pressure vessel through an atmosphere of saturated steam providing heat for thermal-pressure hydrolysis and recovering treated biomass from the vessel. The primary lignocellulose biomass may be prepared in admixture with secondary biomass which may be manure-based. There is also provided a feedstock for anaerobic digestion comprising a fibrous primary lignocellulose biomass in a finely divided state, a secondary biomass providing anaerobically digestible nitrogen and aqueous liquid, the primary biomass having a disrupted cellular structure such that its inherent buoyancy in aqueous liquid is lost and digestible carbon is released and the mixture being in the form of an aqueous slurry in a sterilized state. The feedstock after thermal pressure hydrolysis may be anaerobically digested e.g. by wet mesophilic anaerobic digestion to achieve a high unit throughput and biomethane output thus allowing the deployment of the system at large scale within the anaerobic digestion industry.

A process is provided for preparing a low density, fibrous primary lignocellulose biomass, particularly straw for anaerobic digestion at large scale, i.e. >2 MW.sub.th, which comprises a step that greatly increasing the density of the straw through size reduction, moisture adjustment and compression ahead of loading and subsequent agitation of the resultant biomass in a pressure vessel through an atmosphere of saturated steam providing heat for thermal-pressure hydrolysis and recovering treated biomass from the vessel. The primary lignocellulose biomass may be prepared in admixture with secondary biomass which may be manure-based. There is also provided a feedstock for anaerobic digestion comprising a fibrous primary lignocellulose biomass in a finely divided state, a secondary biomass providing anaerobically digestible nitrogen and aqueous liquid, the primary biomass having a disrupted cellular structure such that its inherent buoyancy in aqueous liquid is lost and digestible carbon is released and the mixture being in the form of an aqueous slurry in a sterilized state. The feedstock after thermal pressure hydrolysis may be anaerobically digested e.g. by wet mesophilic anaerobic digestion to achieve a high unit throughput and biomethane output thus allowing the deployment of the system at large scale within the anaerobic digestion industry.

The present invention regards a refiner plate segment (1) for a disc-type refiner apparatus (30), adapted to grind a saturated cellulosic material (M) in a refining gap (17) defined by opposed discs (20) during use of the apparatus (30), the material being moved from a refiner inlet opening (21) towards an outer edge (7) of the segment (1). The outer edge (7) of the segment (1) comprises a barrier arrangement (15) to increase the pressure in the refining gap (17) for retaining the liquid phase out to said outer edge (7). The present invention also regards a method of refining a saturated cellulosic material (M) in a refining gap (17) defined by two opposed discs (20) of a disc arrangement.

The present invention regards a refiner plate segment (1) for a disc-type refiner apparatus (30), adapted to grind a saturated cellulosic material (M) in a refining gap (17) defined by opposed discs (20) during use of the apparatus (30), the material being moved from a refiner inlet opening (21) towards an outer edge (7) of the segment (1). The outer edge (7) of the segment (1) comprises a barrier arrangement (15) to increase the pressure in the refining gap (17) for retaining the liquid phase out to said outer edge (7). The present invention also regards a method of refining a saturated cellulosic material (M) in a refining gap (17) defined by two opposed discs (20) of a disc arrangement.

It is disclosed an apparatus for separating a least one solid from a solids/fluid mixture, said apparatus comprising a separation chamber and a cushion chamber. The separation chamber comprises a top end, a bottom end, at least one wall, and an inlet port for introducing the solids/fluid mixture, said inlet port having an inlet port vector. The cushion chamber comprises at least one boundary wall, and it is adapted to maintain a cushion of the solids/fluid mixture at an intersection of the inlet port vector and the cushion chamber when the separation chamber and the cushion chamber are connected by a communication port at the intersection of the inlet port vector and the at least one wall. The communication port has an area at least a size of an impact area of the solids/fluid mixture on the at least one wall. The communication port may be formed by the erosion of the at least one wall of the separation chamber caused by the solids/fluid mixture at the impact area. It is also disclosed a process for separating a solids/fluid mixture, wherein the solids/fluid mixture is introduced through the inlet port of the separation chamber and contacted with a cushion of a previously introduced solids/fluid mixture, the solids/fluid mixture being allowed to interact with the cushion of the previously introduced solids/fluid mixture. The at least one solid is separated from the fluid by density difference in the separation chamber. Preferably, the solids/fluid mixture is steam treated lignocellulosic biomass which is inserted in the disclosed apparatus at high velocity.

The invention provides a method for generating a solid wood-based material and a hemicellulose-derived material from a wood raw material. The method includes treating the wood raw material under aqueous conditions at elevated temperature and pressure to generate a hemicellulose-containing fluid component and a solid component; separating the fluid component from the solid component; processing at least a part of the solid component into a solid wood-based material; and processing the liquid component into a hemicellulose-derived material. The invention also provides for a wood-derived fuel with a low ash content.

The steam saving device for a steam explosion system for the hydrothermal pre-treatment of biomass comprises a tubular body 30 with a first open end 32 and a second open end 34. The first open end 32 being adapted to be coupled to an outlet opening 14 of a steam explosion reactor vessel 10, the second open end 34 being adapted to be coupled to a discharge line 18. The inner surface 36 of the tubular body 30 of the nozzle 16 may comprise an engraved helical structure 38.

The steam saving device for a steam explosion system for the hydrothermal pre-treatment of biomass comprises a tubular body 30 with a first open end 32 and a second open end 34. The first open end 32 being adapted to be coupled to an outlet opening 14 of a steam explosion reactor vessel 10, the second open end 34 being adapted to be coupled to a discharge line 18. The inner surface 36 of the tubular body 30 of the nozzle 16 may comprise an engraved helical structure 38.