618results about "Pulp de-watering" patented technology

The present invention provides an apparatus and a method for conversion of cellulosic material, such as chopped straw and corn stover, and household waste, to ethanol and other products. The cellulosic material is subjected to continuous hydrothermal pre-treatment without addition of chemicals, and a liquid and a fibre fraction are produced. The fibre fraction is subjected to enzymatic liquefaction and saccharification. The method of the present invention comprises:performing the hydrothermal pre-treatment by subjecting the cellulosic material to at least one soaking operation, and conveying the cellulosic material through at least one pressurised reactor, and subjecting the cellulosic material to at least one pressing operation, creating a fibre fraction and a liquid fraction;selecting the temperature and residence time for the hydrothermal pretreatment, so that the fibrous structure of the feedstock is maintained and at least 80% of the lignin is maintained in the fibre fraction.

The present invention comprises an improved method for refining cellulose that produces a highly refined cellulosic material in combination with a hydrocolloid. The method comprises soaking raw material from primarily parenchymal cell wall structures in an aqueous solution which need not contain an agent to modify the fiber (e.g., a mild alkalizing or alkaline agent and / or solution) using reduced temperatures and pressures, and refining the material with a plate refiner so that a waste water stream is reduced in volume. The mass is dried to produce the HRC fiber. The HRC fiber displays a water retention capacity of about 25 to at least about 56 g H2O / g dry HRC and retains moisture under conditions that are ordinarily used to remove moisture from materials. The highly refined fiber product can also provide excellent thickening properties and can be used in a wide variety of materials, including edible materials.

A process for separating organic components from a pulp mill waste stream comprising the steps of washing a cellulose pulp to obtain an aqueous extraction liquor containing organic components, and separating at least a portion of said organic components from the extraction liquor by passing the extraction liquor through at least one nanofiltration membrane. The process may be used in conjunction with a variety of pulp mill processes, including kraft cooking processes, hot caustic extraction processes, sulfite cooking processes, and bleaching processes.

Methods of bleaching mechanical pulp under alkaline conditions with hydrogen peroxide. The methods include introducing a source of magnesium ions and hydroxyl ions to a refiner. The wood particulates are refined into a pulp in the presence of the magnesium ions and hydroxyl ions, and optionally perhydroxyl ions to simultaneously refine and bleach the pulp in a refiner.

The present invention discloses a bleached chemical pulp prepared by using graminoid plant as raw material and its preparation method. Said invention is characterized by that it utilizes a high-hardness pulp which is obtained by using cooking process and whose permanganate number is 16-28 and equal to Kappa number 26-50 and makes said high-hardness pulp undergo the processes of pulp-washing and bleaching treatment so as to obtain the invented bleached chemical pulp whose breaking length is 4500-8000 m and folding endurance is 20-70 times.

The invention discloses short linen viscose fiber and a preparation method thereof. The viscose fiber is produced by preparing linen pulp from linen and then using the linen pulp. The preparation method comprises the following steps of: pre-processing, washing, digesting, washing, pulping, degritting, concentrating, alkali refining, whitening, performing acid treatment, washing, finely selecting, degritting, concentrating, papermaking, soaking, squeezing, smashing, aging, yellowing, grinding, dissolving, filtering, defoaming, filtering, spinning, drafting, cutting off, performing post treatment, drying, packaging and the like. The preparation method has the advantages that: the performance of bacterial resistance and bacterial resistance of the linen fiber can be kept better, a finished product has high whiteness, the production period is short, the problems of large digesting intensity, complicated digesting process and the like are solved, and the pollution generated during production is low.

The invention provides a method to remove black liquor by a presser from the high rigidity pulp prepared by cooling the grass materials. Send the cooked pulp which has the rigidity of potassium permanganate value 16-28 (equals to karber value 24-50) into the inlet of the presser for pressing. The pulp discharges from the outlet after removing the black liquor. The invention aims at pressing the low concentration and high rigidity pulp prepared by cooling the grass materials to remove the black liquor. It prepares for the necessary washing and bleaching steps during the processing, advances the bleaching effect and saves the necessary chemicals for bleaching, which is an economic and environmental protection method.

The invention discloses a method that uses esterase obtained by 100 percent deinking and desizing of wasted newspaper controls sticky which mainly aims at producing the low fixed amount newspaper by using the 100 percent deinking and desizing of the wasted newspaper, adopts Optimyze 525 esterase control sticky and produces the newspaper with 45g / mm<2> fixed amount. The invention has the advantages of reducing the dosage of the sticky in the paper pulp, leading the sticky removing rate to be about 20 percent to 40 percent, reinforcing the operating performance of a paper machine, and helping to improve the speed and the output of the paper machine; by adopting deinking and desizing of 100 percent wasted newspaper to make 45g / m<2> lowing amount offset newsprint, the obtained products have good quality, chemical pulp and groundwood pulp which are high in pollution and high consumption are eliminated, the manufactory cost of the pulp material and the processing cost of the water are reduced, and the discharged waste water and the pollutants are reduced.

The application of the invention provides an environmentally-friendly paper making and pulping technique with high yield, which comprises a raw material preprocessing stage, a physical fibrillation impregnating processing stage, an impregnating, steaming and bleaching three-section integrated pulping stage and a thickening and dewatering processing stage. An environmentally-friendly paper making and pulping system with high yield realizing the pulping technique comprises a stock cutter, a hammering and fibrillation screening dust remover, a washing dust remover, dewatering conveying equipment, a spiral steaming conveyor, a crashing, extruding and impregnating machine, a stirring and impregnating cabin, a pump pipe and a discharge pipe of a high-enriched steaming, bleaching and pulping all-in-one machine, wherein the pump pipe is connected to the high-enriched steaming bleaching pulping all-in-one machine; the discharge pipe of the high-enriched steaming, bleaching and pulping all-in-one machine is connected to a pulp cabin; the pump pipe of the pulp cabin is connected with a thickening and dewatering machine; the thickening and dewatering machine is output to the high-enriched pulping machine; the output of the high-enriched pulping machine is connected with a screening purifier and a thickening and squeezing machine in sequence. In the invention, the problems of high pollution, high energy consumption, serious shortage of paper making raw material and the like in present pulping and paper making industry can be solved fundamentally; rich plant fiber in the nature can be used, and the technical purposes of efficient bleaching, high yield, no black liquor and low energy consumption can be realized.

The invention relates to a production technique of a dissolved cotton pulp, in particular to a production technique that utilizes the raw material of cotton linters and adopts simple techniques to produce the dissolved cotton pulp with even fiber length, high fibrillation degree, good intensity, less water soluble substances, high methylcellulose content, stable polymerization degree and less dust, has low COD discharge in waste water, and lowers environmental pollution. The dissolved cotton pulp produced by the production technique is mainly used for producing paper that is used for wiping upper-scale precise instruments, steel paper that is used for precise machining, a novel medicine loading agent of microcrystalline cellulose, explosive nitrocellulose, high-level nitrolacquer and building coating materials, etc.

A pulp making process in which fibrous cellulosic material is pulped to form an aqueous suspension of cellulosic material, the suspension is drained through a screen to form a pulp sheet and that the pulp sheet is dried to form a dry market pulp, in which a water soluble cationic polymer is added to the suspension as the sole drainage aid wherein the water-soluble cationic polymer is either,i) a copolymer comprising (a) between 1 and 70 mole % (meth) acrylamide and (b) between 30 and 99 mole % (meth) acryloyloxyethyltrimethyl ammonium chloride with an intrinsic viscosity between 5 and 9 dl / g; orii) a hydrolysed homopolymer of vinylformamide comprising between 1 and 100 mole % vinyl amine units and having a K value of between 45 and 240.The process of the invention provides improved drainage time and solids content of the dewatered pulp.

The invention discloses an efficient and clean puling and bleaching method dissolving alpha-pulp by Chinese alpine rush. The method comprises the steps of stock preparation, prehydrolysis, alkaline cooking, black liquor extraction, closed screening, total chlorine free bleaching, bleached pulp treatment and the like, namely, adding stock blank after prehydrolysis into a continuous digester to carry out alkaline cooking; adopting a vacuum pulp washer to extract black liquor from sizing agent, sealing and screening, then washing and concentrating the sizing agent through a vacuum filter, wherein the mass concentration of pulp after concentration is larger than or equal to 10%; adding NaOH solution and magnesium salt protective agent in concentrated pulp, then sequentially passing through a medium concentration pump and a medium concentration mixer to enter an upflow type bleaching tower to carry out total chlorine free bleaching. In the invention, the productive process is continuous, and non chlorine bleaching agent is utilized in the production, waste water can flow reversely for reuse and does not contain toxic and harmful adsorbable organic chloride AOX, thereby realizing energy saving and emission reduction, cleaning and bleaching of alpha-pulp production, improving the additional value of Chinese alpine rush, thus the method can be promoted and utilized industrially.

An improved market pulp and process for making the same by adding a composite material are described. The composite material includes cellulose nanocrystals, cellulose nanofibers, or another high aspect ratio, high surface area cellulose material (or a starch, or both) and a crosslinking compound that crosslinks a portion of the surface hydroxyl groups to form a 3-D matrix. Adding the composite material to market pulp has been shown to improve the strength of twice-dried paper products, made from such an enhanced market pulp. By crosslinking a portion of the surface hydroxyl groups in the market pulp to form a 3-D matrix, a first drying step may be accomplished without loss of benefits afforded when the market pulp is later re-pulped to make a paper product.

The present invention relates to a pulping technology, in particular to a clean pulping technique with straw or broad leaves as raw materials. In the technical scheme, the clean pulping technology mainly includes twelve steps: (1) straw cutting or fragmenting and dedusting; (2) a fly cutter material-washing pool; (3) a raw material bin; (4) a press master; (5) the first-stage high-consistency grinding; (6) a reaction bin; (7) a press master; (8) the second-stage high-consistency grinding; (9) a high-consistency bleaching and temperature-keeping bin; (10) pulping; (11) filtering; (12) washing and whiteness enhancement. The technology uses straw or broad leaves as raw materials to realize the pollution-free fiber pulping technique, and applicable to large and medium paper-making enterprises, the whole pulping technique has the advantages of simplicity, low production cost, high yield rate of white pulp, good pulp quality, obvious reduction of energy consumption, etc.

The present invention provides compositions comprising cellulose fibers and cellulose ester fibers and wet laid articles made from the compositions, as well as wet laid processes to produce these compositions. More specifically, the present invention provided compositions comprising cellulose fibers and cellulose acetate fibers and wet laid articles made from these compositions as well as wet laid processes to produce these compositions. The present invention also relates to developing a composition, process, wet laid product, or articles exhibiting any one of many desired benefits.

The invention discloses a method for preparing bleached pulp by using eucalyptus wood chips, and belongs to the fields of pulping and papermaking. The method comprises the following steps: orderly washing, dewatering and presteaming a eucalyptus wood material, carrying out double helix extrusion, chemical impregnation and high-consistency refining, eliminating, washing and the like. A double helix extruder with a variable pitch and a variable diameter is adopted in extrusion and concentration treatment of the material before defibrination; the damage of the traditional extrusion tearing machine to a fiber is avoided; the quality of the prepared pulp is similar to that of the pulp prepared by qualified chips; the bulk of the pulp can achieve over 3.4 cm<3> / g; the whiteness can achieve over 76% ISO (international standardization organization); effective utilization of the eucalyptus wood chips in the fields of pulping and papermaking is achieved; alkaline hydrogen peroxide which is friendly to the environment is adopted in the craft process; a fewer of pollutants are generated in the pulping process and are non-toxic; instant bleaching and subsequent bleaching reaction are achieved by effectively utilizing the heat energy generated in the pulping process; and steam consumption is reduced.

The invention discloses a production method for preparing bamboo dissolving pulp by utilizing natural-color unbleached bamboo pulp in a modifying way, overcoming the defect of poor reaction property of products prepared by an alkali refining method. The production method comprises the following steps of: concentrating and dewatering dredged natural-color unbleached bamboo pulp, and delivering to a double-helix roller type pulp grinder; continuously dewatering in the pulp grinder, and adding liquid medicine; continuously concentrating and kneading the pulp and mixing the pulp with the liquid medicine in the pulp grinder; then delivering the pulp to a stewing machine; and after stewing is completed, conducting subsequent procedures including washing and bleaching till paper making. The invention reduces the preparation cost, enhances the quality of products and increases resource supplying sources; in addition, the bamboo pulp prepared by the production method not only has higher content of alpha-celluloses, but also has good reaction property, and is suitable for filament and staple fibers.

The invention belongs to the technical field of paper strengthening, in particular to a method using starch as a paper dry strengthen agent. The method comprises the following steps: uniformly mixing starch accounting for 0.5-25% of oven dry mass of pulp with pulp, carrying out extrusion and concentration, heating for 8-150min at 70-100 DEG C to gelatinize starch, carrying out defibering and dispersion on the heated pulp, and manufacturing paper with pulp. The invention has simple process, low production cost and less pollution, improves the strength of paper by 30-110%, has above 80% of starch retention ratio, and can improve the retention ratios of fillers and fiber fines.

The invention relates to an OCC line residual pulp efficient recycling production method. The method comprises the steps of low-concentration tailing collecting and conveying, finely-screened tailing collecting and conveying, trench off-machine water total discharged residue collecting and conveying, tailing concentration, tailing pulp grinding, tailing mixing, diluting and concentration regulating, medium-concentration sand removing, fine screening, multi-tray concentration, pulp grinding and pulp storage. The step of trench off-machine water total discharged residue collecting and conveying specifically comprises the steps that total trench off-machine water of OCC line machines is recycled through an inclined screen of a wastewater treating plant, and recycled residual pulp is pumped into a residual pulp treating line after the concentration is regulated. Compared with the prior art, by means of development and application of key processes such as tailing collecting, concentration, re-grinding, diluting, sand removing, fine screening, concentration and fine pulp obtaining and key equipment improvement, fibers and recyclable fine fibers in tailings and filler are efficiently recycled, and the residue pulp treatment line is large in treatment amount and high in yield.

The invention relates to a mechanical method for making pulp by extruding sunflower stems, belonging to the field of paper making and aiming to provide a method for preparing paper making pulp by taking the sunflower stems as raw materials. Severed sunflower stems are firstly delivered into a vertical type depithing machine to carry out depithing by a half wet method and then washed to carry out depithing by a wet method, then the severed sunflower stems are steamed and then enter a twin-screw extrusion impregnating machine, slag charge sheets are extruded and grinded into mass-shaped rough pulp and also impregnated and absorbed by NaOH inside the twin-screw extrusion impregnating machine, the mixed rough pulp enters a reaction chamber to be continuously reacted and then enters a high-concentration attrition mill to mill the rough pulp into highly-concentrated pulp, and the milled pulp is delivered into a latency chest to be diluted, stayed and stirred and finally enters a screw press dewaterer to carry out screw type press and dewatering and extrude finished pulp. The invention has the advantages of low-energy consumption, no pollution, low water consumption (ton paper / 10 tons of water), high intensity, high yielding rate and high benefit.

The invention belongs to the field of paper pulp manufacturing and particularly relates to a method for utilizing a bamboo raw material to produce high-polymerization-degree dissolving pulp. The method is characterized by comprising the steps of material preparation, prehydrolysis, hot alkali extraction, alkaline method cooking, oxygen bleaching, bleaching and acid treatment and the like, and the clean pulping method for the high-polymerization-degree bamboo pulp solves the problems that existing production raw materials for the high-polymerization-degree dissolving pulp is sufficient, the technology falls behind, and pollution is severe, and the like. The polymerization degree of the manufactured bleached bamboo pulp is over 2000, the whiteness is over (90+ / -2)%ISO, a-cellulose is over 96%, the ash content is below 0.1%, the Fe ion is below 20ppm, S18 is below 3%, S10 is below 4%, and (S10-S18) is below 2%.

The present invention relates to a process for purifying a slurry comprising cellulose, such as microfibrillated cellulose, wherein the process comprises the following steps: —providing a slurry comprising cellulose and liquid,—subjecting the slurry to an electric field inducing the liquid of the slurry to flow, —separating the liquid from the cellulose thus obtaining a liquid depleted slurry, —adding a washing liquid, such as an organic solvent, to the liquid depleted slurry—subjecting the liquid depleted slurry to an electric field inducing the washing liquid of the slurry to flow and—separating the washing liquid from the cellulose, thus obtaining a purified cellulose. The invention also relates to cellulose such as microfibrillated cellulose obtainable from said process.

The invention provides writing paper made of slurry comprising the following components by percentage: 20% to 100% of unbleached straw pulp and 0% to 80% of wood pulp. According to the ISO (International Standardization Organization), the whiteness of the writing paper is 35% to 75%; the opacity thereof is higher than or equal to 75%; and the basis weight thereof is 45.0g / m<2> to 80.0g / m<2>. The production process of the writing paper is energy-saving and cost-saving; and the pollutant emission can be greatly reduced.

The invention discloses an ultrahigh-viscosity refined cotton production process. The specific production process comprises the step a of material selection and cotton opening, the step b of soaking, the step c of pretreatment, the step d of digesting, the step e of bleaching and the step f of grinding and drying. In the step d, pretreated alkali fibers are placed into an airtight spherical digester, and the temperature in the spherical digester is raised; next, the spherical digester is rotated in an idle mode, the temperature is raised again while the spherical digester is rotated, and the pressure is controlled to range from 0.20 MPa to 0.22 MPa; next, rotation of the spherical digester is stopped, a small amount of steam is released for 10 minutes, and a part of oxygen in the spherical digester is discharged to prevent oxidation and viscosity reduction; next, the temperature is raised again while the spherical digester is rotated, and the pressure is controlled to range from 0.25 MPa to 0.28 MPa; lastly, a large amount of steam is released after the temperature is kept for 30 minutes, alkali liquor is recovered, and cotton slurry is poured out when the temperature drops to 100 DEG C. The ultrahigh-viscosity refined cotton production process has the advantages that the use amount of the alkali liquor is reduced, the use cost of the alkali liquor is effectively lowered, and the requirement for improving the ultrahigh viscosity of products is met.

The invention concerns a method and a device for the dilution of dewatered cellulose pulp that maintains a consistency of 30% or greater. By shredding of the pulp to a finely divided dry granulate, dilution to a homogeneous consistency in the medium consistency range can take place exclusively through hydrodynamic effects from the addition of dilution fluid. The dilution fluid is added to the granulate at a position at which the granulate is in free fall in a stand pipe 22, 40 and above a level LiqLEV of diluted pulp in the stand pipe. A number of nozzles are arranged around the periphery of the stand pipe, directed in towards the centre of the stand pipe, obliquely downwards in the direction of fall of the granulate. It is possible through this simplified procedure to avoid completely the conventional dilution screws, and this reduces the investment costs and is operating costs, while at the same time unnecessary mechanical influence of the pulp fibres can be avoided.

The invention relates to methods of producing microfibrillated cellulose (MFC). According to the invention a fibrous pulp suspension is fibrillated mechanically at a consistency of less than 12.5%, dewatered to raise the consistency of the fibrillated suspension to at least 12.5%, and then subjected in the dewatered condition to further fibrillation. Alternatively an initially fibrillated fibrous pulp suspension may be dewatered and fibrillated in the dewatered condition, after which these dewatering and fibrillating steps are repeated one or more times so that pulp consistency is increased for each fibrillation step. The goals of raising the consistency between subsequent fibrillations are energy saving and an increased aspect ratio in MFC. The invention even comprises uses of the MFC product, e.g. as an additive for papermaking furnish or injection molded plastic composites.