408results 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.

According to an example aspect of the present invention, there is provided a method comprising: 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 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.

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 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 belongs to the technical field of pulp paper production, and particularly relates to a preparation method of low-dirt-degree and high-strength bleached sulfate mixed broadleaf wood wet wood pulp and pulp board. According to the invention, the acacia mangium chips and the eucalyptus chips are mixed and prepared, so that a foundation is laid for obtaining subsequent high-quality products; mixed wood chips are pre-impregnated in impregnation liquid with the effective alkali content being 4-8 g / L, so that the wood chips can react quickly in the cooking stage, and resin in broadleaf wood is eliminated; the wood chips are cooked, knotted, screened and washed, so that impurities in the slurry can be eliminated again; and by performing oxygen delignification treatment and bleaching on the coarse pulp, the quality of the pulp is improved. Therefore, the mixed broadleaf wood wet wood pulp and wood pulp board prepared by the preparation method disclosed by the invention are excellent in various indexes, low in dust degree, high in tension resistance, tear-resistant and breakage-resistant, and high-quality mixed wood pulp is provided for customers of paper for daily use.

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.

The present invention provides a water-closed cycle waste paper pulping system and a process thereof, which relates to the technical field of pulping devices, and includes: a base, which is a rectangular plate-shaped structure, and is placed on the ground, and a box body with a rectangular box-shaped structure is fixed on the base. The present application, through the arrangement of the second barrel body and the third barrel body, firstly, can precipitate the pulp, and through precipitation, the excess water can be extracted, thereby ensuring the water content of the pulp; secondly, after the excess water is extracted, the water can be decomposed by a decomposition agent, and after decomposition, it can be put into the box body again for continued use, thereby realizing the circulation of water and saving water; the present application, through the arrangement of auxiliary components, firstly, the array-shaped air holes on the annular seat can improve the mixing effect of the pulp in the first barrel body, thereby improving the bleaching effect; secondly, under the telescopic action of the electric cylinder, the height change of the annular seat can be realized, thereby further improving the bleaching effect.

The invention relates to the technical field of refined cotton processing, in particular to an efficient and optimized refined cotton processing production method which comprises the following production steps: S1, preparing materials: selecting cotton linters as raw materials; s2, cotton opening is conducted, cotton linters are placed on a feeding port of a cotton opener, and equipment is started for cotton opening treatment; s3, preparation of a cooking agent: taking quinone and 2-methylquinone as assistants, putting the assistants into sodium hydroxide, sodium carbonate and amino acid salt, and mixing and stirring to prepare the cooking agent; and S4, cooking treatment: putting the cotton linters into the prepared cooking agent, cooking, and reacting sodium hydroxide with cellulose. By regulating and controlling the biological thallus glycolysis process, directional control over the polymerization degree of the product is achieved, the range of the polymerization degree is narrowed, the fiber reaction uniformity is improved, the fluctuation range of the polymerization degree of products of the same specification is smaller than 80, the impurity removal efficiency is improved, the content of impurities, ash and metal ions is reduced, efficient impurity removal and refining are achieved, and the quality of processed refined cotton is improved.

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.

Recycle fiber bleaching includes an oxygen pre-treatment to activate the fiber for further bleaching. A preferred method of making a high brightness papermaking pulp from recycled cellulose fiber includes: (a) pre-treating a first recycled cellulosic fiber mix with oxygen, said first recycled cellulosic fiber mix having a first high Kappa number prior to pre-treatment and a reduced Kappa number after pre-treatment that is lower than said first high Kappa number; and (b) blending the pre-treated first recycled cellulosic fiber mix with the reduced Kappa number with a second recycled cellulosic fiber mix having a second Kappa number lower than the first high Kappa number of the first recycled cellulosic fiber mix; and (c) oxidatively bleaching the blended recycled cellulosic fiber mix of step (b); and optionally (d) reductively bleaching the blended recycled cellulosic fiber mix of step (c).

The invention provides kenaf whole stalk APMP pulp and a preparation method thereof.The preparation method comprises the specific steps that S1, air-dried kenaf whole stalks are cut into strips, washing and impurity removing are conducted, and a material a is obtained; s2, carrying out pre-steaming treatment on the material a, and extruding and defibering the steamed material to obtain a material b; s3, adding the material b into the pre-impregnation liquid for impregnation to form slurry, and performing centrifugal dewatering on the slurry until the concentration is 20-30wt% to obtain slurry a; s4, grinding the pulp a to form high-concentration ground pulp, adding the high-concentration ground pulp into the adjusting liquid a, bleaching, and centrifugally dewatering until the concentration is 20-30wt% to obtain pulp b; s5, the pulp b is added into the adjusting liquid b for second-stage bleaching and centrifugal dewatering till the concentration is 20-30 wt%, pulp c is formed, the pulp c is diluted and ground, cleaning and screening are conducted after grinding is completed, and the kenaf whole stalk APMP pulp is obtained. The kenaf whole stalk APMP pulp has good pulp characteristics, the dependence of traditional APMP pulping on wood is broken through, and the current situation that domestic pulping wood resources are deficient is relieved.

Disclosed are non-wood pulps having a fiber length greater than about 1.70 mm and a Very Long Fiber (VLF) content of about 0.50% or less. The fibers are readily dispersible in water and useful in the formation of fibrous sheets, particularly wet-laid sheets and more particularly wet-laid tissue sheets having a relatively low basis weight. In addition of having a relatively long fiber length and a low VLF content, the pulps may also have a Dispersivity Index of about 2.00 or less, which is indicative of a relatively narrow fiber length distribution. The pulps may be prepared from plants of the family Asparagaceae by mechanical pulping and more preferably by a chemi-mechanical pulping process using an alkaline and hydrogen peroxide where the plant biomass is cut to size prior to pulping.

In some embodiments, a method may include reducing the microbial load in contaminated water of water recycle loops. These water recycling loops may include pulp and paper mills, cooling towers and water loops, evaporation ponds, feedstock processing systems and / or non-potable water systems. The methods may include providing a peracetate oxidant solution. The peracetate solution may include peracetate anions and a peracid. In some embodiments, the peracetate solution may include a pH from about pH 10 to about pH 12. In some embodiments, the peracetate solution has a molar ratio of peracetate anions to peracid ranging from about 60:1 to about 6000:1. In some embodiments, the peracetate solution has a molar ratio of peracetate to hydrogen peroxide of greater than about 16:1. The peracetate solution may provide bleaching, sanitizing and / or disinfection of contaminated water and surfaces. The peracetate oxidant solution may provide enhanced separation of microbes from contaminated water.

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 invention provides a method for preparing nanocellulose by using a phellinus igniarius substrate as a raw material, and belongs to the technical field of green biomass refinement, the method comprises the following steps: crushing and sieving the phellinus igniarius substrate, repeatedly washing with deionized water, and filtering to obtain phellinus igniarius substrate filter residues; bleaching the phellinus igniarius substrate filter residues with alkali liquor and bleaching liquor at the same time to obtain cellulose; the method comprises the following steps: carrying out enzymolysis on cellulose by utilizing an enzymolysis method, and carrying out centrifugal separation, acid flocculation, centrifugal washing and freeze drying to obtain the nano cellulose. The hydrogen peroxide is used for bleaching the cellulose, so that pigments can be effectively removed, the damage to the cellulose is smaller than that of other bleaching agents, and no chemical substance harmful to the cellulose is left after bleaching. By changing the enzymolysis conditions and the centrifugal rotating speed, three different supernates can be separated, and different nano-crystalline cellulose can be extracted from the supernates to meet the requirements of different applications. And resource utilization of the phellinus igniarius substrate is realized, and waste is turned into wealth.

1. A process for bleaching a pulp comprising delignifying the pulp by carrying out the following sequence: an enzyme treatment step comprising contacting the pulp with a glycoside hydrolase family GH11 xylanase enzyme at a pH of at least 9.5 and a temperature of at least 85°C, an oxidation step in which a bleaching agent is added, an alkaline extraction step in which an alkaline agent is added, and recovering the bleached pulp, wherein the GH11 xylanase enzyme has the ability to reduce the viscosity of a xylan-containing mixture at 90°C and pH 10.5 by at least 20% when compared to the same mixture without any xylanase enzyme.

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.

A novel wood fiber production process is characterized by comprising the following steps: a feeding stage: conveying raw materials from a conveyor belt for feeding; in the winnowing stage, the raw materials enter a winnowing desander to be desanded; in the material plugging stage, the raw materials enter a material plugging screw for stable material plugging; in the treatment stage, the raw materials enter a treatment assembly to be treated, and high-strength wood fibers are obtained; in the feeding stage, wood chips with the water content being 50% are adopted as raw materials, the wood chips are existing production waste materials, and the raw materials are shoveled and conveyed to a conveying belt through a forklift; an opening is formed in the upper end of a winnowing sand remover used in the winnowing stage to receive the raw materials on the conveying belt, and an exhaust fan and a bag-type dust collector are matched with the winnowing sand remover to discharge and collect gravel in the raw materials; wood chips / sand are separated through winnowing equipment; through proper material plug spiral type selection, it is ensured that low-density wood chips form a stable material plug; the high-strength wood fiber is obtained by adjusting the proper chemical adding proportion and steam consumption.

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.

An aqueous composition comprising: sulfuric acid; a modifying agent comprising an arylsulfonic acid; and a peroxide. Said composition being capable of delignifying biomass under milder conditions than conditions under which krafit pulping takes place.

A method of treating cellulosic waste material, decolorized cellulosic pulp and uses thereof. The method includes providing a cellulosic waste material containing colouring substances such as color pigments, dyes, colorants, and combinations thereof, pulping the 5 waste material to produce a cellulosic pulp, and decolorizing the pulp with ozone under alkaline conditions. By subjecting recycled textile waste material to ozone treatment in the alkaline range after pulping, excellent whiteness of the pulp is achieved without significantly compromising the viscosity of the pulp.

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.