117results about "Pulp bleaching" patented technology

The present application relates to pulping technology field, the present application provides a kind of high-strength high-cleanliness chemical pulp's pulping process, with bamboo willow edge scrap as fiber raw material, after 1 stage pre-steaming, chip washing, dehydration, 2 stage pre-steaming;The wood chip material after 2 stage pre-steaming is 1 stage extrusion and is dissolved, 1 stage chemical liquid pre-impregnation, 2 stage extrusion and is dissolved, 2 stage chemical liquid pre-impregnation;1 stage chemical liquid pre-impregnation uses sodium hydroxide solution and does not use hydrogen peroxide, the chemical reagent of 2 stage chemical liquid pre-impregnation process is sodium hydroxide, hydrogen peroxide and sodium silicate;Material after 2 stage chemical liquid pre-impregnation is 1 stage refining, separation, cooling, 1 stage high-concentration bleaching, 1 stage dehydration, 2 stage high-concentration bleaching, 2 stage dehydration;Pulp after 2 stage dehydration is latent, refining etc., and the finished product is prepared.This application process can produce high-strength, high-cleanliness chemical pulp, and the pulp cost is lower, and the pulp quality is better, and it is beneficial to high-end cultural paper etc. application.

The invention discloses a chlorine-free environment-friendly bleaching agent for refined cotton. Comprising the following raw materials in parts by weight: 5-18 parts of peracetic acid, 10-30 parts of hydrogen peroxide, 5-8 parts of a sodium alginate / PEG4000 / modified cellulose nanowhisker compound, 1-5 parts of an organic acid catalyst, 0.05-0.5 part of a dipicolinic acid stabilizer, 0.01-0.1 part of a magnesium salt stabilizer, 2-10 parts of a pH buffer solution and 40-60 parts of deionized water. According to the chlorine-free environment-friendly refined cotton bleaching agent disclosed by the invention, efficient bleaching under mild conditions is realized through precise matching of a composite oxidation system and a multi-element synergistic protection system; meanwhile, the invention provides a preparation method and an application process of the bleaching agent, the bleaching agent is adaptive to the existing production line, and enterprise upgrading cost is reduced.

There is provided a bleached high temperature chemithermomechanical pulp and a method for producing said HT-CTMP comprising the steps: a) providing wood chips comprising softwood, hardwood or mixtures thereof; b) impregnating the wood chips with an impregnation liquid comprising NaOH and / or Na2SO3 to obtain impregnated chips; c) transferring the impregnated chips to a heating zone without compressing the impregnated chips; d) heating the impregnated chips in the heating zone with steam having a temperature of above 140 °C, such as at least 150 °C, such as at least 160 °C, to obtain pre-treated chips; e) defibrating the pre-treated chips to obtain a pulp; f) bleaching the pulp to obtain a bleached pulp; and g) refining the bleached pulp at a consistency of 3-8 wt. % to obtain bleached HT-CTMP.

A variant polypeptide of xylanase, and a fusion protein and an enzyme composition comprising the variant polypeptide, a recombinant host cell for production of the variant polypeptide, methods for using it and its use, is disclosed comprising an amino acid sequence having at least 79%, but less than 100% amino acid sequence identity with amino acids 1-191 of SEQ ID NO: 1, wherein the amino acid sequence has xylanase activity, at least one disulfide bridge between two Cys residues in the 1-191 amino acid region, and an amino acid substitution at the position 23 or 28, or at the positions 23 and 28, the positions corresponding to the positions 23 and 28 of the SEQ ID NO: 1.

The invention provides bamboo reed bleached fluff pulp as well as a preparation method and application thereof, and belongs to the field of papermaking. According to the characteristics of low bonding strength and small bursting strength of the arundo donax short fibers and parenchyma cells, the use of chemicals such as a debonding agent and the like is canceled, the preparation process is different from a traditional bamboo fluff pulp preparation process, the components of the arundo donax short fibers are reserved, the three-dimensional structure of the arundo donax bleached fluff pulp fibers is optimized, the water absorption and water retention capacity of the fluff pulp is improved, and meanwhile, the paper pulp yield is optimized. According to the raw material characteristics of the bamboo reed, the process conditions of prehydrolysis, cooking and bleaching are optimized, and an economical and efficient bleached fluff pulp product of the bamboo reed pulp is produced, so that the method has good practical application value.

An article including a first fiber derived from a first natural source and a second fiber derived from a fruit. A method of manufacturing an article may include combining a first and second fiber to form a fiber mixture, where the first and second fibers are obtained from discrete materials, and where at least one of the fibers is derived from an edible fruit of a plant. The article may be formed from the fiber mixture.

The invention provides a composite metal catalyst and application thereof in biological combined light treatment paper pulp bleaching. The method comprises the following steps: dividing and brooming cooked paper pulp fibers by adopting biological pretreatment, and then carrying out illumination bleaching under simulated sunlight irradiation by adopting a metal photocatalyst (ZnO, ZFO, ZAO, ZMO and the like). According to the mild treatment method, the whiteness of the paper pulp is improved, and meanwhile it is guaranteed that fibers are not damaged. Compared with traditional chemical bleaching, biological combined light treatment bleaching has the advantages that the content of pollutants in wastewater is greatly reduced, meanwhile, reacted metal oxides can be recycled, and the combined treatment method can be used as a novel paper pulp fiber bleaching mode.

The application belongs to the technical field of bioengineering, and particularly relates to a high-temperature-resistant laccase mutant obtained by site-directed mutation through an overlapping PCR technique, and preparation and application thereof. The laccase mutant is obtained on the basis of a wild-type laccase shown in SEQ ID NO. 1, and at least one of D221Y, E231D, Y441H or Y441F mutations occurs, and the mutant enzyme activity and the thermal stability at 80 DEG C are both improved to different degrees relative to the wild type, which is beneficial to expand the application in the industrial fields of degrading lignocellulose, paper pulp bleaching and the like.

The present invention relates to a system for treating delignified cellulose pulp, comprising: consecutive first and second washing devices configured to receive and wash delignified cellulose pulp; an acidic bleaching device arranged to receive cellulose pulp from the second washing device; the post-acid-bleaching washing device is connected to the acid bleaching device and is used for washing the cellulose pulp received from the acid bleaching device; an alkaline bleaching device arranged downstream of the washing device; the alkaline bleaching post-washing device is connected to the alkaline bleaching device and is used for washing the cellulose pulp received from the alkaline bleaching device; a filtrate feeding means arranged to recycle the waste washing liquid from the post-alkaline-bleaching washing means as a diluent between the first washing means and the second washing means and / or as a washing liquid to the first washing means; and a source of water and / or condensate connected to the second washing device to provide a washing liquid.

The utility model relates to the technical field of paper pulp bleaching, and discloses a hydrogen peroxide supply device for a wood pulp bleaching process, which comprises an oxygen generator, a water purifier, a liquid caustic soda pressure stabilizing and filtering system, a hydrogen peroxide electrolysis production system, an energy storage system and the like. And an alkaline hydrogen peroxide storage tank is arranged on the outer side of the hydrogen peroxide electrolysis production system. According to the hydrogen peroxide supply device for the wood pulp bleaching process, in order to better control the flow of alkaline hydrogen peroxide, high-purity oxygen is stably supplied through the oxygen generator, and the liquid caustic soda pressure is stabilized and impurities are filtered through the liquid caustic soda pressure stabilizing and filtering device, so that the stable quality of the generated alkaline hydrogen peroxide is ensured; the alkaline hydrogen peroxide outlet flow meter and the alkaline hydrogen peroxide discharging pump work cooperatively, the flow of the alkaline hydrogen peroxide can be accurately controlled according to actual requirements, accurate supply is achieved, and the problem that the bleaching effect is unstable due to fluctuation of the dosage of the hydrogen peroxide is solved.

The present disclosure relates to a modified polypeptide having xylanase activity and the use thereof.

The invention discloses a continuous efficient decolorizing and bleaching system and process for preparing recycled pulp from waste textiles, and belongs to the technical field of waste textile recycling. The decolorizing and bleaching machine with a sectional type screw rod structure, process unit integration and the like is adopted for carrying out pretreatment, decolorizing treatment, first cleaning treatment, bleaching treatment and second cleaning treatment, so that continuous and efficient decolorizing, bleaching and cleaning on the waste textiles (especially the waste textiles containing indigo dyes) under the condition of medium and high concentration (10-30%) are realized; consumption of chemical agents and water resources is reduced, the technological process is shortened, and the technological requirements are met.

The application discloses a kind of high thickness of high bulk pulp and its preparation process, belong to papermaking technical field.The technical scheme is as follows: including the following steps, raw material preparation and pre-soaking treatment, reaction bin reaction, high consistency refining treatment, bleaching, latent elimination, low consistency refining, screening and washing, 1) raw material preparation and pre-soaking treatment: the raw material wood chip is broken, then pre-soaking is carried out, control pre-soaking temperature 80~90 ℃, pH value 9.8~10.2, liquid level ≥50%, ADI back pressure ≥4bar, NaOH dosage is 1.5%~2.0% of dry wood chip weight;2) high consistency refining treatment: the wood chip after pre-soaking is sent into high consistency refiner for refining, refining consistency 35~45%;3) bleaching: pulp after refining is sequentially subjected to one-stage bleaching and two-stage bleaching.The application process has high stability, and can realize the synchronous and stable improvement of bulk and freeness.

The invention provides a bamboo pulp corrugated carton preparation technology, and relates to the technical field of corrugated carton preparation, the bamboo pulp corrugated carton preparation technology comprises the following steps: S1, bamboo pulp paper preparation: S11, pulping, S12, paper pulp blending, and S13, papermaking; s2, corrugated board preparation: pressing the wood pulp paper into core paper by adopting a single-sided machine, coating an adhesive on a corrugated peak part on one side of the core paper by adopting the single-sided machine, so that the core paper and the inner paper are initially adhered to form a single-sided corrugated board, coating an adhesive on a corrugated peak part on the other side of the core paper by adopting a double-sided machine, and adhering the single-sided corrugated board and the surface paper to form double-sided corrugated paper; and S3, corrugated case preparation: forming lap joint grooves in the double-sided corrugated paper prepared in the S2 by adopting a grooving machine, pressing folding lines, and performing die cutting forming by adopting a die cutting machine to prepare the corrugated case. Bamboo pulp is used as surface paper and inner paper, the cost advantage is remarkable, the problems of moisture absorption and embrittlement of a corrugated carton are solved, and the performance defects caused by bamboo pulp fiber short boards are overcome.

The invention relates to the field of pulping and papermaking, in particular to a mediator-free laccase delignification bamboo pulp bleaching method which comprises the following steps: S1, mixing laccase and absolute dry pulp, adjusting pulp concentration, introducing oxygen at a certain temperature for reaction, washing with deionized water, spin-drying and scattering; the absolutely dry pulp is obtained by defibering, screening and drying unbleached chemical bamboo pulp. And S2, carrying out acid pickling chelation on the absolutely dry slurry treated in the step S1. And S3, bleaching the absolutely dry slurry treated in the step S2. According to the method, the lignin in the bamboo pulp is efficiently removed, the kappa number is reduced by more than 40%, the biological enzyme is directly used for replacing about 30% of total chemicals under the condition of not changing the section of an oxygen removal tower in the original process, and the consumption of chemicals and the discharge of bleaching wastewater in industrial production are reduced; and meanwhile, no expensive mediator is added, so that the problem of corrosion of the mediator to equipment is avoided, and the maintenance cost is greatly reduced.

The invention particularly relates to a dissolving pulp production process which comprises the following steps: washing and soaking wood chips or cotton linters, and naturally draining to obtain a pretreated raw material; adding adjusting water into the pretreated raw material, then adding sodium sulfite, mixing and stirring, heating and preserving heat, and extracting pre-hydrolysis waste liquid to obtain semi-slurry; the ratio of the absolute dry mass of the pretreated raw materials to the volume of the adjusting water is 1: (5-8); in terms of SO2, the use amount of sodium sulfite is 2%-4% of the absolute dry mass of the pretreated raw material; the heating and heat preservation temperature ranges from 150 DEG C to 160 DEG C, and the heat preservation time ranges from 90 min to 120 min; carrying out sulfate cooking on the semi-slurry to prepare coarse slurry and cooking black liquor; the coarse pulp is bleached, pulped and sieved by adopting an OD0EOPD1 section sequence, and the dissolving pulp is prepared. According to the method, the quality of the dissolving pulp is remarkably improved by adopting sodium sulfite to prehydrolyze the dissolving pulp, the high-end application requirements of cellulose acetate, Lyocell fibers and the like can be met, the vacuum pulp washing link of semi-pulp after prehydrolysis is omitted, the pulp wastage rate is reduced, the MVR evaporator utilizes secondary steam compression reuse, and the water resource utilization rate is improved.

The application discloses a food-grade high-strength and high-toughness paper pulp, paper products and a preparation method thereof, and belongs to the technical field of papermaking. The food-grade high-strength and high-toughness paper pulp comprises 100 parts of virgin wood pulp, 1-3 parts of alginic fiber, and 0.3-1.5 parts of a wet strength agent, and the wet strength agent is a random copolymer of methyl acrylate, glycidyl ether-based polyethylene glycol monoallyl ether, dihydro-jasmine acid methyl acryloyl oxy hydroxypropyl ester and acrylamide propyl trimethyl ammonium chloride. The alginic fiber and the wet strength agent are added into the virgin wood pulp, so that the strength and toughness of the paper products are improved.

A process for producing sanitized pulp is provided. Also provided is the use of sanitized pulp in the manufacture of paper, cardboard, molded fiber articles, or other fiber-based articles, including sanitized pulp.

The invention relates to the technical field of cellulose treatment processes, in particular to a sterilizing and bleaching process for treating gelatinous cellulose.According to the sterilizing and bleaching process, the gelatinous cellulose is subjected to low-temperature crushing treatment, the specific surface area can be increased, the reagent permeation path can be shortened, and therefore the problem that internal treatment of large gel is not thorough is solved; in the mild baking soda cooking treatment, baking soda is hydrolyzed to generate a weakly alkaline environment, the sterilization effect can be achieved, the sterilization rate is kept to be larger than 99.9%, and carbon dioxide gas generated in the cooking treatment can form microchannels in cellulose, so that subsequent reagent permeation is promoted; in directional sodium percarbonate bleaching treatment, sodium percarbonate is decomposed into sodium carbonate for providing an alkaline environment and hydrogen peroxide for oxidative degradation of pigments when meeting water, so that the whiteness of cellulose can be improved, a thallus membrane structure can be destroyed, and further, the effect of one-step bleaching and sterilization is realized.

A method for recycling textile material comprising cellulose, the method comprising treating (2) the textile material using Hot Caustic Extraction, HCE, and, after said treating, bleaching (4) material obtained from said treating The HCE is carried out at a temperature of at least 100 °C. The bleaching comprises at least one of ozone bleaching at a total ozone charge of more than 5 kg / odt; chlorine dioxide bleaching, and hydrogen peroxide bleaching at a total charge of more than 13 kg / odt.

The application belongs to the field of genetic engineering and enzyme engineering, and particularly relates to a mannanase from a space mutagenized yeast strain, a preparation method, a product and an application thereof. The amino acid sequence of the mannanase is shown as SEQ ID NO. 2, and the nucleotide sequence thereof is shown as SEQ ID NO. 3. The mutant has outstanding performances at high temperature (70% enzyme activity is retained at 85 DEG C for 3 min, while 40% enzyme activity is retained for the original enzyme at 85 DEG C for 3 min) and acidic pH (the stability is increased from 3% to 25% after treatment at pH 3.0 for 180 min), and has low-temperature high-efficiency catalytic characteristics of optimal pH 7.0, optimal temperature 40 DEG C and 30% enzyme activity at 20 DEG C, and has significant application potential in the fields of feed and papermaking industry.

Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with surprisingly low mechanical energy input. In some variations, the process includes fractionating biomass with an acid (such as sulfur dioxide), a solvent (such as ethanol), and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and mechanically treating the cellulose-rich solids to form nanofibrils and / or nanocrystals. The total mechanical energy may be less than 500 kilowatt-hours per ton. The crystallinity of the nanocellulose material may be 80% or higher, translating into good reinforcing properties for composites. The nanocellulose material may include nanofibrillated cellulose, nanocrystalline cellulose, or both. In some embodiments, the nanocellulose material is hydrophobic via deposition of some lignin onto the cellulose surface. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers. These polymers may be combined with the nanocellulose to form completely renewable composites.

The application discloses a method for removing lignin from lignocellulose raw materials by using a catalyst, and comprises the following steps: placing the lignocellulose raw materials into a mixed solution of hydrogen peroxide and glacial acetic acid, and adding a catalyst to cook the lignocellulose raw materials, so that the cooked lignocellulose raw materials are lignocellulose raw materials from which lignin is removed, wherein the catalyst is Mn / Fe / Bi@Al2O3. The method can realize the purpose of removing or separating lignin by adding hydrogen peroxide and acetic acid to produce a synergistic effect with the Mn / Fe / Bi@Al2O3 catalyst, and oxidizing toxic and refractory organic compounds. In addition, the whiteness of the lignocellulose raw materials treated by the method can reach 90ISO, and the finished product with high whiteness and high lignin removal rate can be obtained by one-step method.

The invention belongs to the technical field of papermaking, and discloses bamboo reed bleaching chemical pulp and a preparation method and application thereof.The preparation method comprises the following steps that bamboo reed unbleached pulp is adjusted to the set concentration, sodium hydroxide with the mass percent being 1.5%-4% and a bleaching auxiliary agent with the mass percent being 0.15%-0.3% are added into the bamboo reed unbleached pulp, the oxygen pressure is 0.3-0.6 MPa, the temperature is 85-90 DEG C, reaction is conducted for 50-70 min, and the bamboo reed bleaching chemical pulp is obtained. Carrying out first-stage oxygen delignification; the paper pulp subjected to first-stage oxygen delignification is conveyed to an up-flow reaction tower, sodium hydroxide and bleaching auxiliaries are not added any more, the oxygen pressure is 0.3-0.6 MPa, the temperature is 85-90 DEG C, reaction is conducted for 50-70 min, and second-stage oxygen delignification is conducted; carrying out first chlorine dioxide bleaching on the paper pulp subjected to second-stage oxygen delignification for 50-70 minutes at 72-76 DEG C under an acidic condition; then under the alkaline condition, hydrogen peroxide treatment is carried out for 50-70 min; and finally, carrying out second chlorine dioxide bleaching for 150-200 minutes at 72-76 DEG C under an acidic condition, so as to obtain the product.

The application provides a xylanase mutant and application thereof. The xylanase mutant comprises: (a) a protein which is mutated based on a wild-type xylanase comprising an amino acid sequence shown in SEQ ID NO: 1, and the mutation site comprises any one or more of the following: T256, G67, H137, V173, R180, Y196, L248, I124, F170, A188 or S271; (b) a protein which has more than 70% homology with the amino acid sequence of the protein defined in (a) and has xylanase activity. The xylanase mutant can solve the problem of poor heat resistance of xylanase in the prior art and is suitable for the field of xylanase modification.

The invention discloses a production method and application of bamboo reed dissolving pulp. The production method of the dissolving pulp comprises the following steps: preparing materials, slicing bamboo reeds, tearing and softening, removing dust, cleaning and dehydrating; keeping the temperature at 150-175 DEG C for 90-150 minutes, and carrying out steam hydrolysis; a sulfite solution is adopted, cooking is conducted for 90-150 min at the temperature of 160-180 DEG C till the pH end point ranges from 5.5 to 6.5, and the hardness K of feed liquid ranges from 15 to 21; and then carrying out a coarse pulp washing and screening process, an oxygen delignification process and an A-DO-EOP-D1-D2 bleaching process so as to carry out multi-stage bleaching on the pulp. The bamboo reed is used as a raw material instead of wood, so that the wood is saved, the cost is reduced, the black liquor in the preparation process can be used as fulvic acid fertilizer, secondary solid waste pollution is avoided, and the method is environment-friendly and efficient in utilization. The dissolving pulp prepared by the method meets the standard and has antibacterial property when being applied to fiber materials.

The present disclosure relates to a modified polypeptide having xylanase activity and the use thereof.

The invention discloses a resource utilization method of bamboo waste materials, which comprises the following steps: S1, washing the bamboo processing production waste materials until the water content of the bamboo processing production waste materials reaches 50-60%, then carrying out steam explosion treatment at 180-200 DEG C, obtaining steam explosion liquid containing lignin degradation products at a condensate interface, and recycling the steam explosion liquid containing lignin degradation products at the condensate interface; steam explosion solids containing cellulose are obtained in the material collecting cavity; s2, loading the steam explosion solid into an acid and alkali resistant filter bag, transferring into an enzymolysis system, adding a buffer solution into the enzymolysis system, and carrying out an enzymolysis reaction at 45-50 DEG C to obtain an enzymolysis product; and S3, transferring the enzymolysis product into a hydrogen peroxide solution, controlling the pH value to be 10-11, bleaching at 70-75 DEG C, and drying through a fluidized bed to obtain the cellulose. The cellulose, hemicellulose and lignin extracted by the method are high in purity, the yield of the bamboo waste cellulose is up to 73.2%, the purity is up to 91.6%, and the method has potential application value.

The utility model discloses a spiral mixing and bleaching device which comprises a conveying shell, a spiral mixing and bleaching device, a spiral mixing and bleaching device, a spiral mixing and bleaching device and a spiral mixing and bleaching device, and is characterized in that the conveying shell is provided with a feed port and a discharge port; the conveying and mixing screw comprises a conveying shaft, a spiral blade and a spiral groove are arranged on the conveying shaft, a liquid conveying channel is arranged on the inner side of the conveying shaft, a liquid conveying opening communicated with the liquid conveying channel is formed in the end of the conveying shaft, and an inner liquid adding opening communicated with the liquid conveying channel is formed in the conveying shaft. Liquid medicine is added from the outer liquid adding opening in the conveying shell, namely from the radial outer side of materials, and is added from the inner liquid adding opening in the conveying shaft, namely from the radial inner side of the materials to be in contact with and mixed with the materials, and the materials are conveyed to the discharging opening in the spiral groove, stirred and further mixed with the liquid medicine for bleaching. The liquid medicine is added to the radial outer side and the radial inner side of the material, the contact mixing points of the material and the liquid medicine are increased, and the mixing blind area is reduced, so that the mixing uniformity of the material and the liquid medicine can be improved, and the adding amount of the liquid medicine is reduced.

The utility model relates to the technical field of bleaching equipment, and discloses paper pulp bleaching equipment which is characterized in that a stirring rod is arranged in a tank body, and a main rod of the stirring rod is designed to be a rectangular rod; a telescopic assembly is arranged at the top of the tank body and comprises a rod body, the bottom end of the rod body penetrates through the top of the tank body and is rotationally connected with the tank body, and a stirring rod penetrates through the rod body; the first bevel gear is fixedly arranged on the outer side wall of the rod body in a sleeving mode. The motor I is arranged at the top of the tank body; the bevel gear II is arranged on an output shaft of the motor I and is meshed with the bevel gear I; the top plate is arranged at the top of the stirring rod; according to the bleaching equipment, the telescopic assembly drives a first bevel gear and a second bevel gear to be engaged through a first motor to drive a stirring rod to rotate, meanwhile, a second motor drives an extrusion block to move the stirring rod up and down, and the mixing effect of the stirring rod is improved. According to the bleaching equipment, the protection assembly can shield and protect the exposed part of the assembly through the guardrail, and mistaken touch of workers is avoided.