28results about "Continuous pulping process" patented technology

In one example, a process includes providing a system with a first vessel and a second vessel; providing a biomass comprising lignin, hemicellulose and cellulose fibers into said first vessel; providing an aqueous acidic composition comprising an acid; providing a modifier component; providing a peroxide component; exposing said biomass to said sulfuric acid, modifier and peroxide components, creating a reaction mass; mixing said reaction mass; and allowing said sulfuric acid component and peroxide component to come into contact with said biomass for a period of time sufficient to a delignification reaction to occur and remove a pre-determined amount of said lignin from said biomass. The pre-determined amount may be assessed by determining a first remaining peroxide concentration in the reaction mass, with a suitable apparatus, when said first remaining peroxide concentration is reached, the biomass is transferred to said second vessel.

An apparatus for processing fibrous materials, in particular fibrous material with high stock densities in the HC range, such as waste paper. The apparatus has a pulping module for pulping fibrous material into a fibrous material suspension, and a grading module, coupled to the pulping module, for subsequent grading of the pulped fibrous material suspension. The pulping module has a housing and a first rotor arranged in the housing. The grading module has a housing with a screen for separating the fibrous material suspension fed in into accepted stock and reject, and a second rotor arranged in the housing. The first and second rotors are formed as a common rotor.

A system and method are provided for predictive control of brown stock treatment at a pulp mill. Various online sensors generate output signals representative of actual values for respective process characteristics, each of which are directly or indirectly affected by adjustments to corresponding process variables. A controller uses the output signals or associated measurement data to dynamically set target values for the process characteristics based on a predicted impact of control responses for corresponding process variables. The controller further generates control signals to actuators associated with the respective process variables based on detected variations between the respective actual values and target values. Exemplary brown stock washing control systems may optimize various types of brown stock washing configurations, including for example vacuum drum washers, compaction baffle washers, chemiwashers, direct displacement washers and wash presses. Cloud-based analytics and machine learning may also be implemented to improve the control algorithms over time.

There is provided a manufacturing method for a type II unmodified cellulose fine fiber to obtain a cellulose fine fiber via mercerization of a cellulose, wherein a chemically unmodified cellulose fine fiber can be efficiently obtained by simple steps. A manufacturing method for a type II unmodified cellulose fine fiber is characterized as comprising: a mercerization step of mercerizing a cellulose to obtain a mercerized cellulose; a depolymerization step of reducing a degree of polymerization of the mercerized cellulose to 760 or less to obtain a raw cellulose; a defibration step of defibrating the raw cellulose by adding an alkali metal hydroxide so as to achieve a total concentration of 2.5 to 17.5% to obtain a cellulose fine fiber; and a neutralization step of neutralizing the cellulose fine fiber with an acid.

[Problem] To provide a manufacturing method for obtaining type II unmodified cellulose microfibers through mercerization of cellulose, wherein chemically unmodified cellulose microfibers can be obtain

A process to perform a controlled exothermic delignification of biomass, said process comprising the steps of: - providing a system comprising at least a first vessel and a second vessel; - providing a biomass comprising lignin, hemicellulose and cellulose fibers into said first vessel; - providing an aqueous acidic composition comprising an acid selected from the group consisting of: sulfuric acid; an alkylsulfonic acid; an arylsulfonic acid and combinations thereof; - providing a modifier component; - providing a peroxide component; - exposing said biomass to said sulfuric acid, modifier and peroxide components, creating a reaction mass; - mixing said reaction mass; - allowing said sulfuric acid component and peroxide component to come into contact with said biomass for a period of time sufficient to a delignification reaction to occur and remove a pre-determined amount of said lignin from said biomass; wherein said pre-determined amount is assessed by determining a first remaining peroxide concentration in the reaction mass, with a suitable apparatus, when said first remaining peroxide concentration is reached, the biomass is transferred to said second vessel.

The invention relates to a device (100) for processing fibrous materials, in particular fibrous material with high material densities in the HC range such as waste paper, comprising at least one pulping module (10) for pulping fibrous material into a fibrous stock suspension, and a grading module (10) which is coupled to the pulping module (10) for subsequent grading of the pulped fibrous stock suspension, wherein the pulping module (10) comprises a housing (12) and a first rotor (17) which is arranged in the housing (12), and wherein the grading module (50) comprises a housing (52) with a screen (53), for separating the fibrous stock suspension which is fed in into accepted stock and into a reject, and a second rotor (57) which is arranged in the housing (52).

Provided is a method for producing type II unmodified cellulose microfibers, which is a method for producing cellulose microfibers by mercerizing cellulose, and which can efficiently produce unmodified cellulose microfibers by a simple process. The method for producing type II unmodified cellulose microfibers is characterized by having the following steps: a defibrillation step in which defibrillation is performed by adding an alkali metal hydroxide to raw material cellulose subjected to a mercerization step of mercerizing cellulose to obtain mercerized cellulose and a depolymerization step of reducing the degree of polymerization of the mercerized cellulose to 760 or less, such that the total concentration is 2.5 to 17.5%, thereby obtaining cellulose microfibers; and a neutralization step in which the cellulose microfibers are neutralized with an acid.

The present invention relates to a method for obtaining a cellulosic pulp from a textile, as well as the cellulosic pulp obtained by the disclosed method, and further processing and use thereof.

The invention relates to a prehydrolysis-kraft process where the hydrolysate is withdrawn in a position where withdrawal capacity may be obtained over a longer operational period. According to the inventive process is the first volume of hydrolysate withdrawn from the process made after a moderate alkalization at end of hydrolysis (PR) and within a time period less than 10 minutes. Mechanical agitation and mixing effects in transfersystem (TR) prevents pitch deposits and clogging in top separator screen (31).

Systems and methods are provided for predictive control of brown stock handling at a pulp mill. Various online sensors produce output signals representative of actual values of respective process characteristics, each of which is directly or indirectly affected by adjustments to a corresponding process variable. A controller uses the output signals or related measurement data to dynamically set target values for the process characteristics based on predicted effects of control responses to the corresponding process variables. The controller further produces control signals to actuators associated with the corresponding process variables based on detected differences between the respective actual values and the target values. Exemplary brown stock washing control systems can optimize various types of brown stock washing configurations, including, for example, vacuum drum washers, compaction baffle washers, chemical washers, direct displacement washers, and wash presses. Cloud-based analysis and machine learning can also be implemented to improve control algorithms over time.

An arrangement for installations of monitoring sensors of a vessel 1 for treatment of lignocellulosic material, which vessel (1) has a central pipe (2) comprising at least one concentric pipe (3), which is mounted coaxially within the vessel (1).At least one sensor channel (4) is arranged along the outermost wall of the concentric pipe (3) of the central pipe (2) and that the at least one sensor channel (4) is connected to a cable conduit (5), which cable conduit (5) connects the exterior of the vessel (1) to the at least one sensor channel (4) ) and the sensor channel (4) is several meters long and has plurality of holders (13) for sensors (11) and / or is configured to contain plurality of thermal sensors (11) with their cables (8). An outer wall (6) of the sensor channel (4) may be a concentric pipe on the central pipe (2) or it is welded from both sides of the outer wall (6) onto the central pipe (2). The sensor channel (4) may contain subchannels (7). The sensor channel (4) may be pressurized and / or have means for evacuating leaked liquid from the bottom of the sensor channel (4). The sensor channel (4) may be thermally insulated from the center pipe (2).

There is provided a manufacturing method for a type II unmodified cellulose fine fiber to obtain a cellulose fine fiber via mercerization of a cellulose, wherein a chemically unmodified cellulose fine fiber can be efficiently obtained by simple steps.A manufacturing method for a type II unmodified cellulose fine fiber is characterized as comprising: a mercerization step of mercerizing a cellulose to obtain a mercerized cellulose; a depolymerization step of reducing a degree of polymerization of the mercerized cellulose to 760 or less to obtain a raw cellulose; a defibration step of defibrating the raw cellulose by adding an alkali metal hydroxide so as to achieve a total concentration of 2.5 to 17.5% to obtain a cellulose fine fiber; and a neutralization step of neutralizing the cellulose fine fiber with an acid.

The present invention relates to a method of producing chemical pulp. The method comprises at least the following steps: a) wood chips or other comminuted lignocellulosic fibrous material is treated with a polysulfide-containing cooking liquor in an impregnation stage at a temperature of 90-145 Ό, and b) slurry of fibrous material from step a) is heated into cooking temperature and cooked for producing pulp having a desired kappa number. After step a) mercaptide ions are added into the slurry of fibrous material and the fibrous material is treated at cooking temperature in step b).

Provided are cellulose fine fibers having a type II crystal structure obtained through cellulose mercerization, and a method for producing the cellulose fine fibers and a molded article thereof, which are chemically unmodified cellulose fine fibers that are highly transparent and safe and can be efficiently obtained through a simple process, and a method for producing the type II unmodified cellulose fine fibers and a molded article thereof. [Solution] Type II unmodified cellulose fine fibers are obtained by a mercerization step in which cellulose is mercerized to obtain mercerized cellulose, a depolymerization step in which the degree of polymerization of the mercerized cellulose is reduced to 760 or less, a defibration step in which an alkali metal hydroxide is added to the raw cellulose to defibrate it to obtain cellulose fine fibers, and a neutralization step in which the cellulose fine fibers are neutralized with an acid.

The present invention relates to the production of steam cracked biomass in the form of black pellets in the field of solid biofuels. More particularly, the present invention relates to the production of black pellets from heterogeneous biomass. The objective of the present invention is to produce black pellets with good mechanical strength, good water resistance, and increased heating value.

There is provided a manufacturing method for a type II unmodified cellulose fine fiber to obtain a cellulose fine fiber via mercerization of a cellulose, wherein a chemically unmodified cellulose fine fiber can be efficiently obtained by simple steps. A manufacturing method for a type II unmodified cellulose fine fiber is characterized as comprising: a mercerization step of mercerizing a cellulose to obtain a mercerized cellulose; a depolymerization step of reducing a degree of polymerization of the mercerized cellulose to 760 or less to obtain a raw cellulose; a defibration step of defibrating the raw cellulose by adding an alkali metal hydroxide so as to achieve a total concentration of 2.5 to 17.5% to obtain a cellulose fine fiber; and a neutralization step of neutralizing the cellulose fine fiber with an acid.

The present invention relates to treatment of unbleached or partially bleached or alkaline extracted dissolving pulp with one or more cellulases. The cellulase treatment results in increased viscosity control, reduced viscosity and / or increased reactivity of the final dissolving pulp.

The invention relates to a method for feeding a slurry of chips and liquid to a prehydrolysis reactor in the production of dissolving pulp. The slurry is pumped by using at least one pump to the reactor, and alkali is fed into the at least one pump 5 for adjusting the pH of the slurry to a range of 7-10.

Herein described is a method for alkaline pulping of biomass in an aqueous mixture, comprising a conversion step in which biomass comprising lignin is converted in an aqueous liquor to obtain converted biomass, wherein the aqueous liquor comprises a protective agent, a basic compound, water, and optional additional pulping reagents. Also described are lignin, xylan and cellulose obtainable by said method.

The present invention relates to a process for obtaining cellulose pulp from textiles, to the cellulose pulp obtained by the disclosed process, and to the further processing and use thereof.

The production of steam-cracked biomass in the form of black pellets in the field of solid biofuels. More particularly, the present disclosure relates to the production of black pellets from a heterogeneous biomass. The aim of the present disclosure is to produce black pellets having good mechanical strength, good water resistance and an increased calorific value.

A pulping line comprising: a cooking arrangement (1) arranged to receive wood chips and to subject the wood chips to a cooking process to produce pulp; a screening arrangement (2) arranged to receive the pulp from the cooking arrangement; a waste treatment arrangement (3a-b) connected to the screening arrangement to receive waste from the screening arrangement, the waste treatment arrangement being arranged to convey at least a portion of the waste to the storage device for discarding thereof; and a washing arrangement (4) connected to the screening arrangement, the washing arrangement configured to wash at least a portion of the accepted stock received from the screening arrangement. The waste treatment arrangement, the screening arrangement, and the washing arrangement are arranged continuously within an elongated region portion of the pulping line, such as on an elongated platform. Further, a cooking arrangement is disposed at a first long side of the zone / platform.

A method of heating lignocellulosic material in a digester (20), comprising the steps of: transporting lignocellulosic material (4) as a slurry (2) comprising the lignocellulosic material and a liquid before the lignocellulosic material is added to the contents (14) of the digester, separating a major part of the liquid (6) from the slurry so that only a minor part of the liquid is added to the contents of the digester together with the lignocellulosic material, and heating the lignocellulosic material and the minor part of the liquid by steam before the lignocellulosic material and the minor part of the liquid are added to the contents of the digester, wherein the steam is flash steam generated by flashing black liquor withdrawn from the digester A digester system is also provided.

A method of generating flash steam by leading black liquor via a first conduit (28) from a digester (20) into a flashing vessel (40), accumulating at least part of the black liquor in a buffer volume (40) of black liquor in the flashing vessel, and withdrawing liquor from the buffer volume, heating the withdrawn liquor, and reintroducing the heated withdrawn liquor into the flashing vessel to generate flash steam. An arrangement (100) configured to generate flash steam from flashing black liquor withdrawn from a digester is also provided.

A pulp mill comprising a cooking arrangement (1) arranged to receive wood chips and to subject the wood chips to a cooking process to produce pulp, a screening arrangement (2) arranged to receive pulp from the cooking arrangement, a reject handling arrangement (3a-b) connected to the screening arrangement to receive a reject therefrom, the reject handling arrangement being arranged to convey at least portion of the reject to storage means for disposal thereof, and a washing arrangement (4) connected to the screening arrangement, the washing arrangement being configured to wash at least a portion of an accept received from the screening arrangement The reject handling arrangement, the screening arrangement and the washing arrangement are arranged consecutively within an elongated area portion of the pulp mill, such as on an elongated platform. Furthermore, the cooking arrangement is disposed at a first long side of the area / platform.

The present invention relates to a process for obtaining cellulose pulp from textiles, to the cellulose pulp obtained by the disclosed process, and to the further processing and use thereof.