438 results about "Dissolving pulp" patented technology

The invention relates to a cellulose extracting technology, and specifically relates to a technology that utilizes organic acids to extract cellulose from biomass raw materials in the presence of a hydrogen peroxide catalyst. The technology comprises the following steps: in the presence of a hydrogen peroxide catalyst, utilizing an organic acid to cook biomass raw materials, wherein the organic acid is composed of formic acid with a concentration of 70 to 95 wt% and acetic acid with a concentration of 70 to 95 wt%; extracting and screening so as to obtain screened cellulose pulp; and further bleaching the screened pulp so as to obtain the target cellulose; wherein the cellulose is dissolving pulp or industrial cellulose. The alpha-cellulose content of the cellulose obtained by the method provided by the invention is more than 90 wt%. The technology has the advantages of simple route and low energy consumption.

The present invention relates to a process for the production of xylose and dissolving pulp from xylan-containing biomass, such as hardwood. The invention is based on prehydrolysis of the xylan-containing biomass with SO2 in specified conditions, followed by chromatographic fractionation, nanofiltration or precipitation crystallization of the xylose-containing prehydrolyzate to obtain a xylose product having a xylose content of at least 55% on DS. The dissolving pulp obtained from the process can be used for example for the production of viscose.

The invention relates to a production method for preparing a dissolving pulp by an oxygen-dissolving and continuous-cooking method, which applies the preparation of cotton linters in the production of viscose fibers in the textile industry, and the method comprises the following steps of: I. cotton linter pretreatments: including cotton linter loosening, cyclone separation and dust removal, feeding, two-roll grinding treatment, etc. to the cotton linters by a two-roll pulping machine; and II. oxygen dissolving and continuous cooking: a horizontal continuous cooking digester is adopted to realize the continuous, fast and low-pollution preparation of dissolving cotton pulp through the actions of high temperature, alkali, oxygen or hydrogen peroxide. The horizontal continuous cooking digester includes a pre-reaction bin, a two-roll gauge, a feeding screw, a T-shaped tube, a continuous-cooking tube and a cold discharge device. The method can effectively solve the problems of: cutting, tearing and cell primary wall breakage to the cotton linters by dry method after feed preparation, physical and chemical stripping to mass impurities in the cotton linters, fast accumulation reduction of the cotton linters in a continuous-cooking device and the purification of alpha cellulose under fast accumulation reduction, recycling of waste heat in the production link, and reduction of total amount of COD in a black liquor, and the method has advantages of even cooking and short cooking cycle.

The present invention is process of producing pulp for producing viscose fiber, and solves the technological problem of wood pulp with papermaking level wood pulp sheet. The wood pulp modifying production process includes the following steps: paging the wood pulp sheet, alkali impregnating, dispersing, digesting, washing, depurating, bleaching, secondary washing, and fishing pulp. The process can produce wood pulp with the quality same as that of dissolved pulp and suitable for use in producing viscose fiber, and has low production cost and less environmental pollution.

The invention provides a method for preparing an improved fibrino spinning original solution that ion liquid is used as solvent, which includes: two phases of swelling and dissolution, namely, placing dried fibrino dissolving pulp and 1-butyl-3-methyl imidazole villaumite with 1%-20% water ratio into a dissolution device for uniform mixing, firstly, leaving and swelling in 70-100 DEG. C, then stronger stirring for swelling to plasm shape without dissolution; secondly, raising temperature to 80-125 DEG. C slowly in stirring state, stirring and reducing pressure distillation for removing water component, fibrino can be dissolved completely after 2-8h; finally, reducing stirring speed, and reducing temperature of plasm to 90-100 DEG. C and keeping 30-60 min for obtaining straw yellow spinning original solution. The method provided by the invention has advantages that the spinning original solution is more uniform, dissolution is more fully, gelatin particle in the spinning original solution is reduced, the spinning original solution quality is increased; apparent viscosity of the spinning original solution is reduced, accordingly, solid content in the spinning original solution is increased further.

The present invention relates to a high tenacity, high modulus and low shrinkage lyocell multifilament yarn suitable for use in tire cords and MRG (mechanical rubber goods). The lyocell multifilament yarn is a cellulose-based fiber for industrial applications, which is produced by dissolving pulp having a degree of polymerization (DPW) of 700-2,000 and preferably 800-1,400, and a α-cellulose content of more than 90% and preferably more than 92%, in N-methylmorpholine N-oxide (NMMO) hydrate, at a pulp concentration of 5-15% by weight and preferably 8-13% by weight. The lyocell monofilament according to the present invention is characterized by the following stress-strain profile: (1) the lyocell monofilament analyzed after drying is elongated by less than 3.0% and has an initial modulus of 150-400 g / d, when it was subjected to an initial stress of 3.0 g / d; (2) it is elongated by 3.0-7.0% when it was subjected to a stress greater than the initial stress but smaller than 6.0 g / d; and (3) it is elongated from a tensile tenacity of at least 6.0 g / d until the yarn is broken.

The invention relates to the field of papermaking and discloses a preparation method of hydrophobic oilproof paper. The preparation method includes: 1), making body paper: soaking bleached softwood chemical pulp, and pulping; mixing the bleached softwood chemical pulp, carboxymethyl cellulose, bacterial cellulose and dissolving pulp, making handsheet, and drying to obtain the body paper; 2), dissolving a natural polyhydroxy high molecular material in water, stirring, heating, holding temperature until a system is transparent, stirring, cooling to room temperature to obtain coating liquid, andcoating; 3), drying the body paper after being precoated, using an acyl chloride solution to treat the surface of the body paper, and drying to obtain a finished product. The problem that paper is porous is solved by means of coating the surface of the paper with the polyhydroxy high molecular material which is natural and easy to degrade, and an acyl chloride compound not containing fluorine is used to replace fluorine-containing polymer to endow the paper with hydrophobicity and oilproofness, so that environment friendliness is realized. In addition, paper prepared by the method has good strength performance and printability.

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.

The invention relates to a process for producing a dissolving pulp from a cellulosic starting material using the kraft process, comprising the step of cooking the starting material with a cooking liquor. The process according to the invention characterized in that the starting material is exposed to a steam treatment prior to cooking and that the pulp obtained by cooking is subjected to cold caustic extraction (CCE) in the course of further processing.

The invention provides a preparation method of composite pulp of paper pulp and cotton linter for viscose. By utilizing the method, the unique performances of fibers such as bamboos, woods, bast fibers, bagasse and the like can be combined with the excellent performances of cotton; any other two or more than two of raw materials such as the paper pulp or the bamboos, the woods, the cotton, the bast fibers and the like can be steamed and cooked independently and can be composited and prepared into dissolved pulp at a bleaching stage after being subjected to a series of process treatments. The varieties of the paper pulp used in the invention are not limited from production methods and raw materials and can be unbleached pulp or bleached pulp; through alkali steeping treatment, the difficulty in steaming and cooking the paper pulp is reduced, the prepared dissolved pulp has high content of alpha cellulose and the steeping liquor can be cyclically utilized; and by utilizing the method, the pollution in the pulping process is less and the cyclic utilization of the alkali liquor can be realized.

The invention discloses a manufacturing technique of bamboo dissolving pulp. The manufacturing technique sequentially comprises cropping, screening and removing ashes, washing under standard temperature, sulfate cooking, serosity separation, scrubbing purification, chlorination treatment, alkali treatment, acetic acid bleaching +H2O2 oxidation organic bleaching, acid complex treatment and runnability. The invention effectively shortens the production process and enhances production efficiency of producing bamboo dissolving pulp by bamboo. The dissolving pulp can be used in rayon dissolving pulp, nitrocellulose dissolving pulp, cellulose acetate dissolving pulp and cellulose dissolving pulp. At the same time, the invention enhances the harvesting rate of making bamboo dissolving pulp by bamboo.

The invention relates to a production method of dissolving pulp. The method comprises the steps of pre-hydrolyzing plant fibrous raw materials by water, steam or diluted acid, then digesting the materials by peroxy acid, and processing the materials by hemicellulase, thus obtaining the dissolving pulp. The dissolving pulp produced by the method has the whiteness more than 90% ISO (International Standards Organization), and the content of Alpha-cellulose is more than 92%, and the content of pentosan is less than 2.0%. The method is applicable to wood and non-wood fibrous raw materials.

The invention discloses a special compound feed for crabs. The compound feed consists of soybean meal, rapeseed meal, peanut meal, corn protein powder, spray-dried animal blood cells, fish meal, shrimp meal, four, fish dissolving-pulp protein powder, yeast extract, fish oil, soybean lecithin oil, bentonite, monocalcium phosphate, a mildew preventive, mannan oligosaccharide, glycine betaine, a hulling element, methionine, choline, perilla seed extract, a vitamin premix and a mineral premix. The raw materials of the compound feed are stable in source, high in utilization ratio, balanced in nutrient content and relatively low in cost. The preferred fish dissolving-pulp protein powder enhances the feed attraction of the feed. An advanced puffing process is adopted so as to further improve the utilization ratio and water resistance of the feed and reduce waste and water pollution. Meanwhile, an immune nutrition additive is adopted so as to significantly enhance the immune function and anti-stress capacity of the crabs and significantly increase the survival rate. The compound feed is much greener and more environmentally friendly, and efficiency increase is particularly significant in a high-density river crab breeding mode.

The invention relates to a method for preparing bagasse dissolving pulp and pre-extracting hemicellulose and products thereof; the method comprises the following steps: bagasse preparation which comprises the steps of depithing and washing; prehydrolysis which is carried out in a globe digester or a hydrolysis boiler; wherein, the process conditions are as follows: in the process for depithing and oven-drying bagasse, the solid-to-liquid ratio is 1:0.4-8.0, the hydrolysis temperature is 100-200 DEG C, the hydrolysis time is 15-240min, the pH value of the end point of hydrolysis is 2-5; in the process of the solid-to-liquid separation and washing, the filtrate is collected to prepare extracting solution; dissolving pulp is prepared by residue alkali method. By adopting the method, bagasse dissolving pulp and bagasse extracting solution which is used to prepare oligosaccharides are obtained. Most of pentosan in bagasse can be extracted by controlling the process conditions of the prehydrolysis, the technical route and the process conditions have strong pertinence so that the reactivity and the uniformity of bagasse dissolving pulp can be improved; by improving the traditional dissolving pulp alkali method for pulping, bagasse biorefinery based on dissolving pulp pulping can be realized in engineering so that the production costs for preparing bagasse dissolving pulp and pre-extracting hemicellulose are reduced.

Aiming at the current situation of the cotton dissolving pulp and the wood dissolving pulp and the characteristics of the bamboo and the defects in the existing preparation of the dissolving pulp, the invention provides a method for preparing a chemical bamboo dissolving pulp. The chemical dissolving pulp produced can be widely applied in the cellulose derivative industries such as spinning viscose fiber, nitrocellulose and acetate fiber. The method comprises the following steps of: material preparation, cooking, screening, scrubbing, bleaching and paper making. The cooking procedure comprises two grades of cooking steps, wherein the primary cooking procedure is continuous cooking and the secondary cooking procedure is continuous cooking or intermittent cooking; and the bleaching procedure is elemental chlorine free bleaching or totally chlorine free bleaching. The invention solves the problems existed in the cooking and bleaching procedures. The chemical bamboo dissolving pulp can be prepared with high efficiency, low energy consumption, low material consumption and low pollution.

The invention relates to a method for preparing bamboo dissolving pulp by improved prehydrolysis alkaline process, which comprises the following steps of: bamboo material preparation, in which bamboo is made into bamboo sheets and bamboo threads, the bamboo sheets and threads are washed to remove impurities and dust; pretreatment, which is for removing more organic and nonorganic impurities, and in which the loss of pentosan is less than 2 percent; prehydrolysis, which is carried out at an acid concentration of sulphuric acid and hydrochloric acid of 0.1 to 10.0 weight percent, a temperature of between 80 and 14 DEG C and a liquor ratio of 1:4-15 for 30 to 400 minutes; and alkaline process. The method has the advantages that: the performance index of the bamboo dissolving pulp meets the requirements of viscose fibre pulp and the like; the improved prehydrolysis process allows the major part of pentosan in the bamboo to be hydrolyzed; the hydrolysate can be used as a raw material for xylose, xylitol, L-Arabinitol, ethanol and other products; the improved prehydrolysis process lays a good foundation for cooking and improving the reaction performance of the dissolving pulp; little production cost is added, the treatment load and cost of waste are reduced with the recovery of the products of the prehydrolysis, and the comprehensive cost is the lowest; and the comprehensive utilization of the components of biomass is realized during the pulping process of the dissolving pump.

The invention discloses an energy-saving, environmental-protection and resourced pulping method of plant fibers, wherein the method comprises the following steps: (1) mechanically cutting a raw material; (2) washing with water and dedusting; (3) pretreating; (4) carrying out steam explosion treatment; (5) carrying out hydrolysis treatment, and extracting xylose; (6) carrying out sulfonation treatment, and extracting sodium lignosulfonate; (7) washing with water to obtain a coarse pulp; (8) carrying out pulp grinding treatment, desanding, screening with a pressure screen, washing with water, and squeezing dry to obtain an unbleached pulp with the water content of 60-65%. Hydrogen peroxide is added into the unbleached pulp to bleach the unbleached pulp, so as to obtain a bleached dissolved pulp. The method has a good softening effect on the plant fiber raw material, can extract xylose and sodium lignosulfonate, achieves zero emissions of wastewater by using a membrane separation technology, and has the prominent advantages of less usage of chemicals, prevention of black liquor generation in a traditional pulping process, high yield and relatively low pulping cost.

The invention discloses a method for preparing fibrillation pulp. The method comprises the following steps: (1) pre-treating chopped fibers by a pre-treating agent; (2) Controlling the concentration of the chopped fibers to between 0.1 and 30 weight percent, and jordaning the chopped fibers in the jordaning equipment to obtain the pulp; and (3) dewatering and storing the pulp. The fibrillation pulp prepared by the method can be applied to friction materials, reinforcing materials, battery membranes, PCB base materials, honeycomb core materials or high-performance paper. The method has the advantages that with the method, the key technical problem in the fibrillation pulp preparing process is effectively solved, and the method is wider in application range; the method can effectively improve the preparing efficiency of the fibrillation pulp and save energy consumption; and by the concrete adjustment of process including the pre-treating agent, the pre-treating condition and the jordaning process, the fibrillation pulp meeting the service condition can be prepared according to the service requirement of products, so the method has larger flexibility.

The invention provides a fish meal and fish oil based on leftover bits and pieces of Tilapia mossambica and making method in preparing field of animal fodder raw material. The making method of fish meal comprises the following steps: choosing leftover bits and pieces of Tilapia mossambica as raw material; producing fish meal after boiling, pressing, drying, disintegrating, sizing and packaging. The making method of fish oil comprises the following steps: doing solid-liquid separation of pressing liquid through pressing step; centrifuging the liquid at high-speed to get upper layer oily substance being fish oil; thickening sub-layer fish dissolving pulp to return fish meal to improve yield rate. The invention processes leftover bits and pieces of Tilapia mossambica to be high grade fish meal and fish oil in changing waste into treasure way with totally-enclosed during the whole process and improves yield rate and prevents polluting environment through waste gas retracting device at the same time, which achieves one level domestic fish meal request in every index of quality belonging an environment-friendly product with fine quality that substitutes domestic fish meal absolutely.

The invention discloses a eucalyptus dissolving pulp and a production method thereof, wherein the eucalyptus dissolving pulp is prepared after the steam prehydrolysis, sulfate cooking, oxygen delignification and D0EoPD1 bleaching of eucalyptus pieces, the whiteness is not less than 88%, the alpha cellulose is not less than 94.5%, the pentosan is not higher than 3.0%, the dynamic viscosity is 9-25mPa s, the ash content is not higher than 0.1%, and the iron content is not higher than 15mg kg<-1>. The production method of the eucalyptus dissolving pulp comprises the following steps that: the eucalyptus pieces undergo the steam prehydrolysis, and the P- factor of the steam prehydrolysis is 300-800; the sulfate cooking is carried out after the steam prehydrolysis of the eucalyptus pieces to obtain the pulp; the eucalyptus chemical pulp undergoes the D0EoPD1 bleaching after the oxygen delignification; and after the bleaching, the pulp is washed, dried and processed into the eucalyptus dissolving pulp.

The invention discloses a method for making dissolving pulp by oxidative degradation of cotton linters in the oxidative degradation method, aiming at resolving the problems of serious pollution, low yield, long cycle and insufficient resources, etc. existing in the conventional process of making dissolving pulp. The method comprises the following technological steps of cutting and impurity removal, high consistency mixing pretreatment and impurity removal and poly decreasing by continuous oxidative degradation. The method of the invention has the advantages of improving production speed, improving product quality, saving steam and lowering the generation of pollutants.

Aiming at current situations of cotton and wood dissolving pulp, characters of bamboo material and many disadvantages existing in the existing whiten method for preparing dissolving pulp, the invention provides a whiten method for preparing bamboo material chemical dissolving pulp. The chemical dissolving pulp produced by the invention can be widely applied to derivant industry of celluloses, such as spinning viscose fiber, cellulose nitrate, acetate fiber, etc. The whiten method in the invention uses element-free chlorine bleaching or total chlorine free bleaching, thereby solving the problems existing in the whiten method of bamboo material chemical dissolving pulp and preparing bamboo material chemical dissolving pulp high-efficiently with low energy consumption, low material consumption and low pollution.

The invention belongs to the technical field of biochemical environmental protection and provides a method for comprehensively treating and utilizing dissolving pulp black liquor. The method comprises the steps of (1) acidification, (2) flocculation, (3) oxidation, (4) adsorption and (5) biochemical treatment and further achieves sewage discharge up to the standard. By means of the method for comprehensively treating and utilizing the dissolving pulp black liquor, flue tail gas, slag and other wastes can be completely utilized, treatment cost is saved remarkably while emission of the three wastes is reduced, flocculated precipitate can serve as a raw material for producing organic fertilizers, considerable economic benefit is produced, chemical oxygen demand (COD) of water subjected to adsorption treatment is reduced by more than 85%, chroma is reduced by more than 99%, and the water can be recycled and can be subjected to biochemical treatment and then discharge up to the standard. The method is reasonable in process, low in cost and easy to implement, and has good economic benefit, environmental benefit and social benefit.

The present invention relates to a kind of method that utilizes bamboo to make paper pulp, relate to firstly splitting bamboo vertically and transversely and then going through the process of screening and washing to reduce the consumption of medicines in the process of prehydrolysis and pulping and make it easy to react, thereby A method of making pulp from bamboo and its pulp that can produce better-quality, higher-yield dissolving pulp, and that can prevent the generation of dioxins by using the bleaching method of ECF or TCF. Since the anthraquinone caustic soda method using anthraquinone as a catalyst is used in the cooking process, the effects of improving delignification and pulp quality and increasing pulp yield are obtained. Also, the content and degree of polymerization of α-cellulose can be arbitrarily adjusted according to the characteristics of the man-made fibers produced as desired by adjusting the conditions of prehydrolysis, cooking and bleaching. At the same time, by recovering xylose produced in the dissolving pulp manufacturing process, it is used to manufacture xylitol, seasoning, furfural, etc., thereby contributing to the improvement of resource utilization and economic efficiency of waste.

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 discloses bamboo fiber dissolving pulp and a production technology thereof. Bamboo is used as a material in production by using the technology, and the technology adopts the following production procedures of: preparing bamboo wood, hydrolyzing bamboo sheets in advance, performing displacement cooking of sulfate, washing and dressing in a sealing way, performing ECF (extracellular fluid) bleaching and refining, and papermaking by pulp. The displacement cooking and the ECF bleaching are used for producing the bamboo fiber dissolving pulp; a product is good in quality, high in yield, high in alpha-cellulose content, low in pentosan content, few in ashes and impurities, and even in viscosity, good in reacting property, high in whiteness, and not easy to yellow. The production of subsequent procedures is facilitated; and the bamboo fiber dissolving pulp is bleached by ClO2 without chlorine element, and the damage to the environment can be greatly reduced.

The invention discloses a stewing process for preparing wood dissolving pulp by utilizing natural-color unbleached papermaking-grade wood pulp in a modifying way, overcoming the defect of poor reaction property of products prepared by an alkali refining method. The stewing process conditions of natural-color unbleached wood pulp in a stewing device are as follows: liquor ratio is 1:2.5-7.0; alkali charge includes 10-50% of NaOH and 0.1-50% of Na2S; a temperature increasing condition comprises the following steps of: increasing temperature to 115-130 DEG C for 30-60 minutes, and keeping the temperature for 30-120 minutes; continuously increasing the temperature to 135-150 DEG C for 30-60 minutes, and keeping the temperature for 120-180 minutes; after the temperature is kept, continuously increasing the temperature to 165-175 DEG C, and keeping the temperature for 30-180 minutes; after the temperature is kept, reducing the temperature, and discharging; and stewing to end after the discharging. The wood pulp produced by the stewing process not only has higher content of alpha-celluloses, but also has good reaction property, and is suitable for filament and staple fibers.

The invention relates to the technical field of production of regenerated cellulose fiber, in particular discloses a complex enzyme preparation applied in the preparation of dissolving pulp and a technique for preparing the dissolving pulp by using the enzyme preparation. The complex enzyme preparation is divided into a complex enzyme preparation I and a complex enzyme preparation II, wherein the complex enzyme preparation I mainly consists of feruloyl esterase, lipase and the like; and the complex enzyme preparation II mainly consists of xylanase, cellulase and the like. The complex enzyme preparation is applied in the technique for purifying alpha-cellulose and preparing the dissolving pulp; and the technique comprises the following steps of impurity removal for raw materials, enzyme method pretreatment, enzymolysis pulping, chelation treatment, alkali hydroxyl active oxygen cooking, acid treatment, washing, sand removal and pulp mixing. The method has the simple preparation technique, and adopts the complex enzyme preparation to treat the raw material pulp so as to effectively remove lignin, hemicellulose, pectin substance and waxiness and to reduce the degree of polymerization of the alpha-cellulose; the energy consumption is low under the normal pressure condition; the COD (Chemical Oxygen Demand) value of the pulping waste water is low; the yield of the dissolving pulp is high; the alpha-cellulose has high content and uniform degree of polymerization; and the production requirements of viscose can be satisfied.

The present invention discloses method which prepares bleaching dissolved pulp using corn-straw, it slurries using the alkali mode of one boiling and three heating-up after impregnating corn-straw in alkaline solution. It includes the production steps: preparing raw materials, dipping, feeding, boiling, washing materials, beating, former classification, chlorin-alkalization, bleaching, acid treatment, washing in water, rear classification, coarsing pulp and preparing the products. The method can produces the corn-straw into high grade slurry used for preparing viscose fiber, the slurry boiled is easier to be bleached, and the method has simple technology and easy operation, it greatly reduces the heavy environmental pollution caused by the waste disposals of pulping waste liquid after pulping production.

Disclosed is a process for producing pulp utilizing bamboo, comprising finely cutting the bamboo into short segments and subjecting the cut bamboo to screening and washing processes to thereby produce dissolving pulp capable of achieving reduced consumption of chemical agents used during pre-hydrolysis and pulping processes and case of reaction, and having superior quality and high yield. Further, provided are also a process for producing fiber (dissolving) pulp utilizing bamboo, capable of preventing generation of dioxin by bleaching the pulp via ECF or TCF bleaching, and a pulp produced using the same.