The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank, wherein the absolute pressure in the blow tank is maintained below atmospheric pressure. The slurry of biomass separated in the blow tank is then enzymatically treated.

The invention relates to an improved method for generating clean steam in a digester plant of a chemical pulp mill. By feeding a steam-to-steam converter (SSC) with venting steam from a black liquor flash tank (FT) as well as venting steam from chip steaming (SV) could the volume of clean steam produced be increased by over 40-50%, and to such an extent that the volume of clean steam covers the needs for preheating of chips in the digester system also in severe operational conditions. The total consumption of clean steam from the steam net of the mill may be reduced and used for other purposes such as electricity production, which meets the requirements for converting the pulp mill to an environmental friendly pulp mill.

The invention relates to an improved method for generating clean steam in a digester plant of a chemical pulp mill. By feeding a steam-to-steam converter (SSC) with venting steam from a black liquor flash tank (FT) as well as venting steam from chip steaming (SV) could the volume of clean steam produced be increased by over 40-50%, and to such an extent that the volume of clean steam covers the needs for preheating of chips in the digester system also in severe operational conditions. The total consumption of clean steam from the steam net of the mill may be reduced and used for other purposes such as electricity production, which meets the requirements for converting the pulp mill to an environmental friendly pulp mill.

The presently disclosed subject matter relates to a horizontal reactor system that can be used for processing various plant material biomass to produce fermentable carbohydrates, paper and pulp products, or both. Particularly, the disclosed system comprises a horizontal reactor vessel comprising a body with first and second ends. The reaction vessel is intended to encompass and retain a reaction medium (i.e., biomass slurry) that is to undergo a biological and/or biochemical reaction. The vessel comprises an internal agitator that functions to mix the contents of the reactor. The agitator is powered by a drive, which can be a motor, positioned outside the reaction vessel.

The presently disclosed subject matter relates to a horizontal reactor system that can be used for processing various plant material biomass to produce fermentable carbohydrates, paper and pulp products, or both. Particularly, the disclosed system comprises a horizontal reactor vessel comprising a body with first and second ends. The reaction vessel is intended to encompass and retain a reaction medium (i.e., biomass slurry) that is to undergo a biological and/or biochemical reaction. The vessel comprises an internal agitator that functions to mix the contents of the reactor. The agitator is powered by a drive, which can be a motor, positioned outside the reaction vessel.

A process for producing refined cotton with a high polymerization degree includes: a. selection of material; b. impurity removal; c. impregnation; d. pretreatment: compounding triethanolamine, sodium carbonate, copper sulfate and magnesium oxide in equal proportion to form a cooking compound adjuvant with a mass concentration of 0.2-0.5%, putting the cooking compound adjuvant into a spherical digester together with the cotton linter subjected to the impregnation treatment, heating to 70 C, stopping heating, and subjecting to idling pretreatment for 40-60 min; e. cooking; f. cooling of the spherical digester; g. formulating a chlorine dioxide bleaching stabilization solution; h. a first stage of bleaching; I. alkali treatment; J. a second stage of bleaching; K. dechlorination; and l. rolling and drying by baking.

A process for producing refined cotton with a high polymerization degree includes: a. selection of material; b. impurity removal; c. impregnation; d. pretreatment: compounding triethanolamine, sodium carbonate, copper sulfate and magnesium oxide in equal proportion to form a cooking compound adjuvant with a mass concentration of 0.2-0.5%, putting the cooking compound adjuvant into a spherical digester together with the cotton linter subjected to the impregnation treatment, heating to 70 C, stopping heating, and subjecting to idling pretreatment for 40-60 min; e. cooking; f. cooling of the spherical digester; g. formulating a chlorine dioxide bleaching stabilization solution; h. a first stage of bleaching; I. alkali treatment; J. a second stage of bleaching; K. dechlorination; and l. rolling and drying by baking.

A process to perform a controlled exothermic delignification of biomass comprises providing a system having a first vessel and a second vessel, providing a biomass comprising lignin, hemicellulose and cellulose fibers placed into the first vessel, providing an aqueous acidic composition comprising a sulfuric acid component, providing a modifier component and providing a peroxide component. The biomass is exposed to the sulfuric acid component and peroxide component, thereby creating a reaction mass. The reaction mass is mixed and the sulfuric acid, modifier and peroxide components are allowed to come into contact with the biomass for a period of time sufficient for a delignification reaction to occur and to remove a predetermined amount of the lignin from the biomass. The predetermined amount is assessed by testing a first kappa number of the biomass. When the first kappa number of the biomass is reached, the biomass is transferred to the second vessel.

A process to perform a controlled exothermic delignification of biomass comprises providing a system having a first vessel and a second vessel, providing a biomass comprising lignin, hemicellulose and cellulose fibers placed into the first vessel, providing an aqueous acidic composition comprising a sulfuric acid component, providing a modifier component and providing a peroxide component. The biomass is exposed to the sulfuric acid component and peroxide component, thereby creating a reaction mass. The reaction mass is mixed and the sulfuric acid, modifier and peroxide components are allowed to come into contact with the biomass for a period of time sufficient for a delignification reaction to occur and to remove a predetermined amount of the lignin from the biomass. The predetermined amount is assessed by testing a first kappa number of the biomass. When the first kappa number of the biomass is reached, the biomass is transferred to the second vessel.

In general, the present invention is directed to a method of cooking wood in a cooking liquor medium. The method comprises a step of providing wood to a treatment vessel and contacting the wood with a digester additive composition. The composition comprises a first surfactant comprising an anionic surfactant, a derivative thereof, a salt thereof, or any combination thereof and a second surfactant comprising a polyoxyalkylene glycol or a derivative thereof. Additionally, according to another embodiment, the present invention is directed to a digester additive composition comprising a first surfactant comprising an anionic surfactant, a derivative thereof, a salt thereof, or any combination thereof and a second surfactant comprising a polyoxyalkylene glycol or a derivative thereof.