14results about "Continuous pulping process" patented technology

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.

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.

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.

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.

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 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 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.

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.