308results about "Pulp bleaching" patented technology

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 fiber length or pulp yield. The high degree of brightness and relatively long fiber length makes 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% debris prior to bleaching.

The invention discloses a method for preparing high-quality dissolving pulp from low-grade plant fiber raw materials, and belongs to the technical field of biomass pulping. The preparation method comprises the following steps: screening a low-grade plant fiber raw material to obtain a fiber raw material of which the length is 20-30 mm, the width is 10-15 mm and the thickness is 3-5 mm; carrying out deep prehydrolysis-sulfate cooking treatment on the screened fiber raw materials to obtain unbleached sulfate pulp fibers; performing deep eutectic solvent and elemental chlorine-free bleaching treatment on the unbleached sulfate pulp fiber to obtain paper pulp fiber with low kappa number; and carrying out biological enzyme treatment on the paper pulp fibers with low kappa number to obtain the high-quality dissolving pulp. According to the method, the morphology and the structure of chemical pulp fibers are effectively regulated and controlled by designing deep eutectic solvent treatment, and deep dissolution of residual hemicelluloses and lignin is achieved; through biological enzyme treatment, the alpha-cellulose content and the Fock reaction performance are further improved, and finally the high-quality dissolving pulp is prepared.

The invention relates to the technical field of bamboo pulp bleaching, and particularly discloses a method for preparing all-chlorine-free bleached bamboo pulp and application. The method adopts a three-section enhanced bleaching process and comprises the following steps: firstly, decomposing lignin under an alkaline condition of 100-115 DEG C through oxygen delignification (Op section); removing transition metal ions by using sulfuric acid and a metal chelating agent with a specific structure by adopting acid pickling chelation (AQ section); and finally, deeply oxidizing the residual lignin in a high-pressure oxygen environment through oxygen enhanced bleaching (Po section). In each stage, hydrogen peroxide is used as a main bleaching agent, sodium hydroxide, sodium silicate and other assistants are matched, and ineffective decomposition of hydrogen peroxide is effectively inhibited through staged pH regulation and a metal chelation technology. The whiteness of the obtained bamboo pulp is larger than or equal to 83% ISO, the kappa number is smaller than or equal to 3.0, and the requirements of high-grade paper products are completely met.

The invention discloses sugarcane syrup suitable for lyocell fiber production and a preparation method and system of the sugarcane syrup, and belongs to the technical field of lyocell fiber production. According to the present invention, the sugarcane pulp for lyocell fiber production is prepared sequentially through the first high-concentration alkali treatment, the second low-concentration alkali treatment, the bleaching, the acid washing and the drying, and the processes are matched for use, such that the conditions are milder compared with the traditional pulping and papermaking cooking process and the oxygen delignification, the equipment requirement is low, the production energy consumption is low, and the operation is safe; according to the present invention, the raw material does not need to be crushed, the index of the finally prepared raw material can meet the Lyocell production requirement, the operation process is simple, the industrial application prospect is provided, the production system matched with the method is provided, and the industrial and continuous production of the sugarcane syrup suitable for Lyocell fiber production is achieved.

The invention discloses a method for producing a green packaging material by using field planting tobacco waste, which comprises the following steps: by taking tobacco stems as raw materials, extracting to obtain high-purity nicotine, extracting active chemical components to obtain tobacco stem residues, primarily treating the residual tobacco stems by an extruding and tearing machine to cut off and separate the tobacco stems into shreds, and drying the shreds to obtain the green packaging material. The cut tobacco stems enter a closed reaction bin, steam heating is adopted, ammonium sulfite or sodium sulfite and sodium hydroxide are added, EDTA and the ammonium sulfite or sodium sulfite and sodium hydroxide solution can dissolve fibrous adhesive lignin in the tobacco stems, and the tobacco stems can be used for producing green packaging materials after further mechanical treatment. Tobacco stem waste residues obtained after nicotine and pectic substance extraction are used as plant fiber paper pulp for producing the green packaging material, holocellulose in the tobacco stem residues is fully recycled and subjected to high-value resource utilization, the waste recycling value is increased, and the problem of waste environmental pollution is solved.

The present technology relates to fluff pulp having improved odor control and methods of making such fluff pulp. A fluff pulp is provided that includes bleached kraft fibers and a copper ion content of from about 0.2 ppm to about 50 ppm by weight of the bleached kraft fibers. The bleached kraft fibers include a length-weighted average fiber length of at least about 2 mm, a copper number of less than about 7, a carboxyl content of greater than about 3.5 meq / 100 grams; an ISO brightness of at least 80; and a viscosity of from about 2 cps to about 9 cps.

The invention discloses an chemi-mechanical pulp production method capable of improving the filtration property of chemi-mechanical pulp, and relates to the technical field of papermaking, high-concentration grinding freeness is optimized to 640 + / -30ml, pulp fine fibers can be controlled at 22%-33%, the tensile index middle-lower limit and the bulk middle-upper limit, the high-concentration grinding effect is improved, the effect between fibers is facilitated, the effect between the fibers and a grinding sheet is reduced, and the filtration property of the chemi-mechanical pulp is improved. Fiber cutting is reduced, and the content of pulp fine fibers is reduced; the MSD torque is increased to 250 + / -10 KNM, the tearing effect of wood chips is improved, the preimpregnation reaction of the wood chips is facilitated, the original fine content is controlled to 26%-29% from original 22%-33%, the pulp bulk is increased by about 0.1 cm < 3 > / g, and the tensile index is increased by 1.0 N.m / g; the four low-concentration grinders are changed into parallel connection, so that the residence time of pulp in the low-concentration grinders is prolonged, the cutting effect of the pulp ground by the low-concentration grinders on fibers is reduced, light friction between grinding sheets and the fibers is increased, fibrillation of the fibers is facilitated, the bulk and the tensile strength are improved to a certain extent, and under the content of fine fibers, the size of the fibers is reduced. And the bulkiness and the tensile index of the finished pulp are also improved to a certain extent.

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.

This method for producing a cellulose material comprises: a hydrothermal treatment step for subjecting a plant biomass to a hydrothermal treatment in an acid aqueous solution; and a bleaching hydrothermal treatment step for subjecting the plant biomass, which has been subjected to the hydrothermal treatment step, to a hydrothermal treatment in an alkaline aqueous solution containing a bleaching agent.

This application provides a method for applying a plant-extracted bioenzyme to paper pulp treatment. Specifically, it involves applying plant-extracted peroxidase to the pre-bleaching delignification treatment of mechanical pulps from bamboo, reeds, and eucalyptus using H2O2. Key parameters in the treatment process, such as enzyme dosage, treatment time, and H2O2 addition, are optimized. The optimal treatment scheme is determined by measuring the total lignin and surface lignin content and fiber morphology of the treated samples. This optimal scheme is more effective in improving the fiber strength and brightness of the treated pulp compared to conventional enzyme treatment methods. Furthermore, molecular docking simulations are performed using a model of the plant-extracted peroxidase and lignin model compounds (LMCs) with different degrees of polymerization to obtain information on the interaction between the enzyme and LMCs, revealing the mechanism of action between peroxidase and lignin. This provides reliable evidence and technical reference for the feasibility of using plant-extracted peroxidase to remove surface lignin from mechanical pulp and promote subsequent H2O2 bleaching.

The utility model discloses a paper pulp bleaching device which comprises a bleaching tank, a top cover is detachably mounted at the top of the bleaching tank, a transmission shaft is rotatably mounted at the center of the top cover, a first bevel gear is sleeved outside the transmission shaft, a speed reducing motor is mounted on the top cover through a support, and the output end of the speed reducing motor is in transmission connection with the transmission shaft. The bleaching agent is uniformly fed into the bleaching tank through the dosing mechanism, the mixing of paper pulp and the bleaching agent is accelerated by matching with the stirring of the stirrer, and the position of the semicircular cavity can be adjusted up and down under the matching of the connecting piece, so that the free switching of the conveying height of the bleaching agent is completed, and the problem that the conveying height of the bleaching agent cannot be changed in the transmission dosing process is avoided. The problem that the bleaching agent cannot be in full contact with paper pulp is solved, the two dosing mechanisms can be adjusted to be arranged at the same height or different heights according to needs, the bleaching agent can be smoothly put into the bleaching tank at different liquid levels, the bleaching precision is improved, and operation of technicians is facilitated.

The utility model discloses bamboo pulp bleaching equipment which comprises a machine body, a partition plate is fixedly installed in the machine body, a water pump is fixedly installed on one side of the machine body, a liquid inlet pipe is fixedly installed at one end of the water pump, and the liquid inlet pipe is inserted into the machine body and located below the partition plate. A feeding pipe is fixedly installed on the machine body and located below the partition plate, a second liquid outlet pipe is fixedly installed at the liquid outlet end of the water pump, a second rotating shaft is inserted into the machine body and rotationally connected with the machine body, and a water inlet groove is formed in the top of the second rotating shaft; one end of the second liquid outlet pipe is inserted into the water inlet tank, and a second bevel gear is fixedly mounted on the outer side of a second rotating shaft. According to the device, a fused solution is guided into the water inlet tank through the water pump, then the liquid outlet holes in the solution flow dividing rod are thrown out through the first motor, and the effect that the solution makes contact with bamboo pulp more evenly is achieved.

The invention discloses a manufacturing method of an environment-friendly paper product. The environment-friendly paper product is prepared from the following raw materials in parts by mass: 60-70 parts of a main fiber raw material, 25-35 parts of an auxiliary fiber raw material, 3-8 parts of an environment-friendly additive and 1-2 parts of a pretreating agent. By means of the components, by adding the auxiliary fiber raw materials, the environmental protection property is remarkably improved, waste cotton and linen and agricultural waste are converted into papermaking raw materials, consumption of primary fibers is reduced, meanwhile, waste recycling is achieved, and pollution caused by incineration and landfill is reduced. The auxiliary fibers and the main fibers have a synergistic effect and are matched with the environment-friendly auxiliaries to reinforce the quality of the paper, the cotton and linen fibers improve the flexibility, the agricultural waste fibers enhance the stiffness, lignin and short fibers are separated through low-temperature pyrolysis, impurities are prevented from affecting the performance of the paper, and solid powder rich in the lignin and the short fibers is recycled and reused.

According to an exemplary embodiment of the present invention, a method is provided that includes providing a pulp composition, screening the pulp composition to obtain an accept fraction and a reject fraction, and dewatering the accept fraction output from the screening by a screw press.

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.

The present disclosure relates to a method for producing chemithermomechanical pulp, CTMP, comprising: a) providing wood chips comprising softwood, hardwood or a mixture thereof; b) storing the chips at a temperature of 45-75 °C for at least 24 h in an aerobic environment to obtain matured chips; c) impregnating the matured chips with an impregnation liquid to obtain impregnated chips; d) transferring the impregnated chips to a heating zone; e) heating the impregnated chips in the heating zone with steam to obtain pre-treated chips; f) defibrating the pre-treated chips to obtain a pulp; and g) dewatering the pulp.

A packaging paper for sharp-edged objects and / or objects having unevenly arranged, protruding, substantially non-deformable elevations on at least one of the surfaces of the object, consisting of kraft pulp as the main constituent and fillers, starch, sizing agent and additional process aids. The packaging paper containing at least 95% primary pulp having a length-weighted average fiber length of at least 2.0 mm and cationic starch and other process aids. The packaging paper has an elongation at break in the machine direction (MD) according to ISO 1924-3:2005 of at least 6.0%, a puncture energy index according to DIN EN 14477:2004 at a test speed of 10.0 mm / min, measured on any side of the packaging paper, in the range of 30 to 75 mJ·m2 / kg and a kappa number according to ISO 302:2015 of between 35 and 38.

The present invention relates to the field of biotechnology, and specifically relates to β-1,4-endoxylanase XlyAE10, its encoding gene and applications thereof. The xylanase XlyAE10 provided by the present invention is a β-1,4-endoxylanase XlyAE10 with excellent properties, good pH stability and heat resistance. The optimal temperature of this enzyme is 60.0 °C, and the optimal pH value is 5.5. It still maintains 50% of its activity within the range of pH 4.0 - 9.0, and has 93.26% of its enzyme activity at 65.0 °C. It can be applied to high-temperature biotechnology fields such as food, feed, textile, pulp bleaching and energy development, and has broad application prospects.

The invention relates to an impurity removal method of a chlorine dioxide vertical generator, which comprises the following steps: adding first pure water and a sodium hypochlorite solution into the chlorine dioxide vertical generator, continuously boiling under a vacuum condition, cooling and discharging liquid; washing with second pure water and discharging liquid; the boiling temperature is lower than 80 DEG C. Different from the prior art, the technical scheme provides a mode for efficiently removing impurities in a mode that the sodium hypochlorite solution is boiled at the temperature lower than 80 DEG C, the boiling temperature in the mode is lower than the efficient decomposition temperature 80 DEG C of hypochlorite, the hypochlorite is high in stability, the decomposition amount is small although the hypochlorite is boiled, and therefore the impurity removing efficiency is higher; the chlorine dioxide vertical generator impurity removal device has the advantages of simple and effective impurity removal of the chlorine dioxide vertical generator, no residue, reduction of the decomposition of chlorine dioxide, and improvement of the production efficiency and the production safety.

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 present application relates to the field of genetic engineering and protein modification technology, and particularly relates to a novel basic xylanase mutant. The present application is based on wild-type xylanase H1, and provides a mutant containing at least one mutation site of Q24P, S38V / K / W / H / T / I, G40M / R / K / F / H, D41P, N56L / I / P / K, A57E / D / Y, A59K / R / I / M / H, H61F / Y, A75S, T80M, T103I, T107E, T114Y, D129L, Q132R / M, D135M, N143D, K144R, T149L, Q151N / Y, C154N, D157E, A160E, N165D, V166I, N167S / W, T177V, D192E. The tolerance of the mutant to high temperature and alkaline environment is significantly improved, which is beneficial to its wide application in the field of papermaking.

The invention discloses a pulping method of bleached chemical pulp, which comprises the following steps: (A) adjusting the concentration of pulp after cooking reaction with water, and adding bio-enzyme and oxidizing compound for oxygen removal reaction to obtain pulp after oxygen delignification; (B) bleaching the paper pulp subjected to oxygen delignification with chlorine dioxide to obtain bleached paper pulp; (C) carrying out alkali extraction on the bleached paper pulp to obtain the bleached chemical pulp, the biological enzyme is one or more of xylanase, hemicelluloses hydrolase, laccase, fiber oxidase, lignin peroxidase and multifunctional peroxidase. According to the method, specific bio-enzyme is added in an oxygen removal section, a common oxygen removal section is converted into bio-enzyme and oxygen bleaching delignification, delignification of a rear section is selectively improved, the load of front-section cooking can be released, the use amount of caustic soda for oxygen removal and cooking is reduced, and the production cost is reduced. Meanwhile, the oxygen removal efficiency, the subsequent bleaching efficiency and the sustainable production level of the paper pulp can be improved.

Processes disclosed are capable of converting biomass into high-crystallinity nanocellulose with low mechanical energy input. In some variations, the process includes fractionating biomass with sulfur dioxide or a sulfite compound 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.

A white liquor oxidation apparatus (1) comprising: a detector (2) disposed inside an oxidized white liquor process flow configured to measure at least one characteristic of the process flow by spectroscopy; and a controller (3) connected to the detector to receive measurement data from the detector. The controller (3) is configured to determine the amount of at least one substance in the process flow according to the measured data and control the white liquid oxidation process according to the determined amount of at least one substance.

The invention discloses a method for preparing tobacco stem-pinus khasys mixed fluff pulp, which comprises the following steps of: performing two-stage hot water pretreatment on tobacco stems to dissolve out hot water soluble substances of the tobacco stems, pulping residues by adopting an oxygen-alkali method, and performing screening and ECF three-stage bleaching to obtain bleached tobacco stem pulp; the method comprises the following steps: pulping pinus khasys by using sulfate, screening, carrying out oxygen delignification and carrying out ECF three-section bleaching to obtain bleached pinus khasys pulp, enabling tobacco stems to have poor water absorption and good water-retaining property due to short fiber length, and preparing fluff pulp with good water absorption by matching long-fiber pinus khasys and short-fiber tobacco stems; the solid waste tobacco stems are subjected to resource utilization, and meanwhile a solution thought is provided for solving the problem that domestic fluff pulp long fiber forestry resources are not abundant.

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.