Disclosed are non-wood pulps having a fiber length greater than about 1.70 mm and a brightness of about 80% or greater. The relatively high degree of brightness is achieved without a loss of fiber length or pulp yield. The high degree of brightness and relatively long fiber length make the pulps well suited for the manufacture of wet-laid fibrous products, particularly wet-laid tissue products. The pulps may be prepared from plants of the family Asparagaceae by mechanical pulping and more preferably by a chemi-mechanical pulping using a sodium hydroxide alkaline peroxide solution where the primary pulp is cleaned to reduce debris prior to bleaching. Preferably the cleaned primary pulp has less than about 5 wt % debris prior to bleaching.

Disclosed are non-wood pulps having a fiber length greater than about 1.70 mm and a brightness of about 80% or greater. The relatively high degree of brightness is achieved without a loss of fiber length or pulp yield. The high degree of brightness and relatively long fiber length make the pulps well suited for the manufacture of wet-laid fibrous products, particularly wet-laid tissue products. The pulps may be prepared from plants of the family Asparagaceae by mechanical pulping and more preferably by a chemi-mechanical pulping using a sodium hydroxide alkaline peroxide solution where the primary pulp is cleaned to reduce debris prior to bleaching. Preferably the cleaned primary pulp has less than about 5 wt % debris prior to bleaching.

Methods of producing cellulosic or lignocellulosic materials for use in papermaking include treating a cellulosic or lignocellulosic dry feedstock having a first average molecular weight with ionizing radiation, and controlling the dose of ionizing radiation such that the average molecular weight of the feedstock is reduced to a predetermined level. A method of producing an irradiated paper product includes treating a paper product including a first carbohydrate-containing material having a first molecular weight with ionizing radiation, and controlling the dose of ionizing radiation so as to provide an irradiated paper product with a second carbohydrate-containing material having a second molecular weight higher than the first molecular weight. Pulp and paper products are produced.

Methods of producing cellulosic or lignocellulosic materials for use in papermaking include treating a cellulosic or lignocellulosic dry feedstock having a first average molecular weight with ionizing radiation, and controlling the dose of ionizing radiation such that the average molecular weight of the feedstock is reduced to a predetermined level. A method of producing an irradiated paper product includes treating a paper product including a first carbohydrate-containing material having a first molecular weight with ionizing radiation, and controlling the dose of ionizing radiation so as to provide an irradiated paper product with a second carbohydrate-containing material having a second molecular weight higher than the first molecular weight. Pulp and paper products are produced.

The invention relates to a method for impregnating biomass (10). In a step (S100) of the method, a reactor unit (11) is fed with biomass (10) by means of a plug screw (12). In another step (S200), the reactor unit (11) is at least partially filled up to a predetermined fill level (13) with a reactant (18), such that a reaction between the fed biomass (10) and the reactant (18) takes place in order to obtain an impregnated biomass. In another step (S300), the impregnated biomass (10) is discharged from the reactor unit (11) for further processing (S300). The invention further relates to a device (1) for impregnating biomass (10).

The invention relates to a method for impregnating biomass (10). In a step (S100) of the method, a reactor unit (11) is fed with biomass (10) by means of a plug screw (12). In another step (S200), the reactor unit (11) is at least partially filled up to a predetermined fill level (13) with a reactant (18), such that a reaction between the fed biomass (10) and the reactant (18) takes place in order to obtain an impregnated biomass. In another step (S300), the impregnated biomass (10) is discharged from the reactor unit (11) for further processing (S300). The invention further relates to a device (1) for impregnating biomass (10).

Hydrothermal pretreatment of mechanically compressed straw in unagitated reactors provides a simple and inexpensive solution to poor C5 monomer yields with autohydrolysis processes. Unlike raw straw, compressed straw pellets or briquettes can be pretreated on commercial scale using unagitated batch reactors or simplified unagitated continuous systems. The chemistry of hydrothermal pretreatment is thereby altered such that loss of C5 sugars to unwanted byproduct reactions is reduced. With compressed straw, water content can be introduced within the reactor while it is pressurized, which reduces energy costs and capital expense. Provided are methods of processing straw feedstocks using semi-continuous or continuous systems and a pretreatment reactor adapted to processes compressed straw with high throughput through a small reactor volume in which water content is added within the reactor under pressure.

In alternative embodiments, provided are methods and industrial processes for generating pulp from lignocellulosic feedstocks, comprising directly contacting a lignocellulosic feedstock with a system comprising a super critical or sub-super critical fluid or mixture of fluids, whereby the partial pressure of the system provides for the hydrolysis or a combination thereof of the feedstock at reduced temperatures and pressures, followed by an upgrading step wherein a low-purity cellulosic material generated in the super critical or sub-super critical reaction step is treated with an alkaline solution. In alternative embodiments, provided are systems and methods for producing a cellulose material using reduced amounts of water.

The invention relates to a method for removing lignin from lignocellulosic biomass. The method comprises feeding of lignocellulosic biomass and a first aqueous solution into a reactor vessel, the lignocellulosic biomass and the first aqueous solution forming a reaction mixture; reducing the pressure in the reactor vessel below 0.8 bar absolute pressure, preferably 0.5 bar absolute pressure, more preferably below 0.2 bar absolute pressure; keeping the reaction mixture in a predetermined extraction temperature, and adding at least one extraction chemical, such as base or acid, to the reaction vessel and extracting lignin from the biomass to the liquid phase of the reaction mixture.

The invention relates to a method for removing lignin from lignocellulosic biomass. The method comprises feeding of lignocellulosic biomass and a first aqueous solution into a reactor vessel, the lignocellulosic biomass and the first aqueous solution forming a reaction mixture; reducing the pressure in the reactor vessel below 0.8 bar absolute pressure, preferably 0.5 bar absolute pressure, more preferably below 0.2 bar absolute pressure; keeping the reaction mixture in a predetermined extraction temperature, and adding at least one extraction chemical, such as base or acid, to the reaction vessel and extracting lignin from the biomass to the liquid phase of the reaction mixture.