1409 results about "Papermaking" patented technology

The invention relates to the technical field of intelligent manufacturing, discloses a papermaking equipment fault tracing method and system based on a process knowledge graph, and discloses the papermaking equipment fault tracing method and system based on the process knowledge graph. The method and the system comprise data acquisition and preprocessing, papermaking process knowledge graph construction, fault event detection and matching, fault tracing and propagation path reasoning, and maintenance scheme recommendation and optimization. The method overcomes the limitation that the traditional method is difficult to capture the cross-equipment, cross-process and cross-time sequence deep causal association and fault propagation path of the papermaking equipment. By constructing a comprehensive papermaking process knowledge graph, equipment operation state data, process parameter data, production quality data, equipment structure principle, process flow knowledge, fault mode knowledge, maintenance experience and other heterogeneous knowledge are subjected to deep fusion and semantic association, so that the system can exceed the correlation of the data surface; and an internal mechanism and a propagation chain of the fault are deeply excavated.

A method of making an absorbent structure including mixing ultra-high molecular weight (“UHMW”) glyoxalated polyvinylamide adducts (“GPVM”) and / or high molecular weight (“HMW”), glyoxalated polyacrylamide and / or high cationic charge glyoxalated polyacrylamide (“GPAM”) copolymers and high molecular weight (“HMW”) anionic polyacrylamide (“APAM”) with the furnish during stock preparation of a wet laid papermaking process.

The invention relates to the technical field of papermaking, and particularly provides high-strength tipping base paper for cigarettes and a preparation process of the high-strength tipping base paper. The tipping paper base paper for the cigarettes comprises a fiber raw material; functionalizing the nano cellulose; a cellulase; a dry strength agent; a wet strength agent; and a sizing agent. Nano cellulose is functionalized and a synergistic stepped enhancement mechanism is constructed, so that the synergistic breakthrough of the high-strength raw tipping paper for cigarettes in the aspects of strength, wet strength and air permeability is realized; after the functionalized nanocellulose is subjected to carboxylation treatment, the hydrogen bond and electrostatic adsorption between the functionalized nanocellulose and the fiber are enhanced, and the bonding strength in a dry state and a wet state is remarkably improved; meanwhile, the wet strength agent is added in stages, and the adsorption sequence of the dry strength agent is optimized, so that the reinforcing agent constructs a stable three-dimensional network framework in the paper sheet, and the end breaking risk under high-speed winding is effectively reduced.

The invention relates to the field of drying cylinder processing, in particular to papermaking drying cylinder body welding processing equipment which comprises a center rod, a first fixing mechanism and a second fixing mechanism are installed on the left side and the right side of the center rod respectively, and a left-right adjusting mechanism for pushing the second fixing mechanism to move left and right is further installed on the right side of the center rod. A rotating cylinder located between the first fixing mechanism and the second fixing mechanism is rotationally installed on the outer side of the center rod. The inner clamping blocks and the outer clamping blocks are matched with each other to clamp the inner side and the outer side of the barrel, the corresponding inner clamping blocks and the corresponding outer clamping blocks are connected and locked through the locking assemblies, the adjacent inner clamping blocks are supported and locked through the supporting assemblies, and the inner clamping blocks, the supporting assemblies and the outer clamping blocks form triangular supporting structures on the inner side and the outer side of the barrel correspondingly; and the stability and firmness of cylinder fixing are improved, and then the stability and welding quality of the welding mechanism during welding are improved.

The invention relates to the field of intelligent manufacturing, in particular to a papermaking process intelligent parameter adjustment method and system oriented to energy consumption optimization, and the method comprises the following steps: S1, obtaining a historical production and energy consumption report, a product quality standard, a productivity plan, an equipment capability curve and safety red line, and an energy price and carbon emission coefficient, and defining a multi-objective optimization function and constraint; s2, acquiring production process data, and preprocessing the data to obtain time sequence sample data; s3, performing feature construction based on the time sequence sample data to obtain a feature set, and constructing a process-energy consumption directed acyclic graph by adopting NOTEARS to obtain a causal atlas; s4, constructing a short-term energy consumption prediction model and a quality prediction model, and performing short-term energy consumption prediction and quality prediction based on the feature set, the causal atlas, the target KPI and the constraint; and S5, performing multi-objective strategy optimization according to the objective function and constraint, short-term energy consumption prediction and quality prediction results. On the premise of ensuring the product quality and the production safety, the energy consumption of a unit product can be effectively reduced.

A method of making an absorbent structure including mixing ultra-high molecular weight (“UHMW”) glyoxalated polyvinylamide adducts (“GPVM”) and / or high molecular weight (“BMW”), glyoxalated polyacrylamide and / or high cationic charge glyoxalated polyacrylamide (“GPAM”) copolymers and high molecular weight (“BMW”) anionic polyacrylamide (“APAM”) with the furnish during stock preparation of a wet laid papermaking process.

The invention discloses environment-friendly high-barrier packaging paper and a preparation method thereof, and belongs to the technical field of paper product manufacturing. The method comprises the following steps: dispersing bleached sulfate softwood pulp in an aqueous solution of TEMPO and NaBr, adding a NaClO solution, adjusting the pH value, carrying out a reaction, washing the product obtained by the reaction, and carrying out high-pressure homogenization to obtain TEMPO oxidized nanocellulose (TOCNF); mixing the bleached sulfate softwood chemical pulp, hardwood pulp and viscose fibers, pulping, papermaking and the like to obtain original paper; then, TOCNF and waterborne epoxy modified acrylic emulsion are mixed, and a mixed coating is prepared; and finally, coating the surface of original paper with the coating according to a certain mass ratio, and carrying out hot-pressing curing to obtain the environment-friendly high-barrier packaging paper. The packaging paper is excellent in mechanical property, high in barrier property, good in surface uniformity and printing property, environment-friendly and degradable in raw materials, simple to prepare and low in cost.

The present invention belongs to the technical field of special paper preparation, and particularly relates to a production method of high-strength aluminized base paper, comprising the steps of: S1, beating: respectively beating long-fiber primary pulp and short-fiber primary pulp, wherein the beating degree of the long fiber is 40-50°SR, and the beating degree of the short fiber is 20-30°SR; S2, adding additives: adding modified inorganic filler, cationic starch and retention aid to the short-fiber pulp; S3, pulp mixing: mixing the long-fiber pulp and the short-fiber pulp according to a weight ratio, and then adding modified bamboo fiber, and uniformly stirring to form a mixed pulp; S4, wire drawing and papermaking; S5, spraying a surface treatment agent; S6, paper drying, calendering and winding. The aluminized base paper obtained by the production method of the high-strength aluminized base paper of the present invention has the advantages of high strength and good smoothness.

The invention provides a method for increasing the content and distribution uniformity of filler in paper sheets and increasing the strength of the paper sheets, and belongs to the technical field of papermaking. The method for improving the content and distribution uniformity of the filler in the paper sheet and increasing the strength of the paper sheet comprises the following steps: preparing a modified composite nanofiber dispersion liquid, preparing a positive electric buffer solution, preparing a positive electric composite slow release solution, preparing a filler particle suspension liquid, and mixing and manufacturing paper with pulp. According to the method for improving the content and the distribution uniformity of the filler in the paper sheet and improving the strength of the paper sheet, the flocculation speed of the filler can be mildly and effectively controlled, the size of floccules can be controllably adjusted, the distribution uniformity of the filler in the paper sheet can be improved while the content of the filler in the paper sheet is improved, and the paper sheet strength is improved. The adverse effect on the mechanical property of the paper sheet caused by filler dosage increase is effectively avoided, and the paper sheet strength is further improved.

The invention relates to the technical field of sewage treatment equipment, in particular to a papermaking sewage cleaning device which comprises a pretreatment box, a filter screen plate is arranged at the bottom in the pretreatment box, a positioning groove is formed in the lower surface of the filter screen plate and slidably connected with a positioning rod, the bottom of the positioning rod is fixed to two limiting frames, and the two limiting frames are fixed to the side wall of the pretreatment box. The upper side of the moving frame is connected with a brush plate, and the lower side of the moving frame is connected with a first driving assembly. A soft scraper is fixed to the filter screen plate and fixed to a connecting frame, and the top of the connecting frame is connected with a second driving assembly. Inserting holes are formed in the side walls of the connecting blocks and are in sliding connection with bent rods, and the tops of the bent rods are connected with adjusting assemblies. The double-sided automatic cleaning mechanism enables the filter screen plate to be brushed up and down synchronously, so that blockage is avoided, shutdown cleaning is not needed, and continuity is guaranteed. The filter screen plate can be conveniently replaced by a single person through a quick insertion structure, and the maintenance difficulty is reduced. Impurities are automatically guided and collected, stability and resource recovery are improved, and maintenance cost and downtime are reduced.

The invention discloses a production process of high-folding-resistance corrugated base paper, and particularly relates to the technical field of corrugated paper production. The process comprises the following steps: mixing and hydraulically pulping different types of waste paper raw materials to obtain original waste paper pulp with the concentration of 2.5-2.8%; original waste paper pulp enters a classifying screen after being subjected to high-concentration sand removal, coarse screening and low-concentration sand removal, and fibers in the waste paper pulp are screened into long fibers and short fibers; mixing the long fiber pulp and the short fiber pulp in proportion, and carrying out papermaking and surface sizing treatment; wherein the papermaking comprises the steps of forming a net part, squeezing and dehydrating, and drying in a pre-drying part to obtain initial corrugating base paper with the dryness of 90-92%, then carrying out surface sizing treatment on the initial corrugating base paper by using a boiled glue solution, drying at 60-100 DEG C until the dryness is 85-92%, and curling and slitting to obtain the high-folding-resistance corrugating base paper. Stable production of the high-folding-resistance corrugated base paper is achieved through raw material diversification, fiber refining treatment, papermaking process flexible regulation and control and glue solution accurate preparation.

The invention discloses a cellulose paper-based diaphragm for a zinc-iodine battery as well as a preparation method and application of the cellulose paper-based diaphragm. The diaphragm is of a three-layer composite structure and comprises a matrix layer formed by paper pulp fibers such as softwood pulp, hardwood pulp, bamboo pulp or straw pulp through a wet papermaking technology, and compact functional layers which cover the two sides of the matrix layer and are formed by oxidized nanocellulose (TOCN). The preparation method mainly comprises the following steps: preparing the paper-based diaphragm matrix through wet papermaking, coating the two sides of the paper-based diaphragm matrix with TOCN aqueous dispersion, and finally carrying out hot-pressing drying treatment to enable the three layers to be tightly combined. According to the invention, the nano aperture and the surface negative electricity functional group of the TOCN layer are utilized, so that physical blocking and electrostatic repulsion of polyiodide ions can be realized at the same time, and the shuttle effect is effectively inhibited; and the uniform pore channels can guide zinc ions to uniformly deposit and inhibit dendritic crystal growth. The diaphragm is green in raw material, simple in process and low in cost, and the cycle life and coulombic efficiency of the battery can be remarkably improved when the diaphragm is applied to the zinc-iodine battery.

A method of making paper and paperboard products comprising absorbent structures is disclosed. The method comprises mixing an ultra-high molecular weight ("UHMW") glyoxalated polyethylene amide ("GPVM") adduct and a high molecular weight ("HMW") anionic polyacrylamide ("APAM") with ingredients in the raw material preparation process of the wet laying papermaking method. High wet strength paper and paperboard products are also disclosed.

The intelligent energy-saving fan operation control method comprises the steps that a plurality of sampling points are preset in a workshop, a reference light source is arranged on the opposite side of the sampling points, and the light source emits polarized light with preset intensity to penetrate through a dust area; acquiring environment image data of sampling points preset in a workshop; analyzing dust concentration data of the sampling points according to the environment image data; according to the position relation between each sampling point and the corresponding fan and the dust concentration index, the initial power of the corresponding fan is calculated through a distance weighting algorithm; and monitoring the dust concentration change rate of each region in real time, and dynamically adjusting the power of each fan by adopting a PID (Proportion Integration Differentiation) algorithm when detecting that the dust concentration change rate of the target region reaches a critical value. The dust concentration in the workshop is analyzed based on the environment image data, the fan power is dynamically adjusted, accurate response to dust concentration changes in different areas is achieved, and therefore the fan operation efficiency is improved, and energy waste is reduced.

The invention discloses a process for preparing paper from wormwood-sourced wormwood fibers, which comprises the following steps: by taking the wormwood fibers as a main raw material, pre-dehydrating, dehydrating, frying carbon, screening, pre-treating, pulping, screening and purifying, concentrating, drying, adsorbing, spraying latex, drying and shaping, and rolling, so that the dependence on imported raw materials in the papermaking process can be effectively reduced; the production cost can be effectively reduced while the production steps are reduced, the paper yield is improved, the agglomeration is reduced, the structure is stable, the environmental pollution in the papermaking process is reduced, the energy consumption is reduced, and the method is safer and more environment-friendly.

The invention relates to the technical field of papermaking wastewater treatment, and provides papermaking wastewater environment-friendly treatment equipment which comprises an air floatation tank, a fixing frame, an aeration mechanism, a supporting frame, a primary filtering mechanism and a secondary filtering mechanism, the aeration mechanism and the supporting frame are oppositely arranged, and the aeration mechanism is used for introducing gas into wastewater in the air floatation tank; the primary filtering mechanism and the secondary filtering mechanism are both rotationally arranged on the supporting frame, the secondary filtering mechanism is arranged on the primary filtering mechanism in a sleeving mode, the primary filtering mechanism is used for filtering waste water conveyed into the air floatation tank, and the secondary filtering mechanism is used for filtering foam on the liquid level in the air floatation tank; according to the technical scheme, the equipment for treating the papermaking wastewater is used for solving the problem that in the prior art, the size of impurities treated by equipment cards for treating the papermaking wastewater is relatively single.

The invention discloses a grab bucket sediment grabbing control method, a grab bucket sediment grabbing control system and a grab bucket sediment grabbing control device based on torque detection, relates to the technical field of material grabbing equipment control, and is particularly suitable for accurate sediment grabbing in industries such as papermaking and sewage treatment. Dynamic judgment of sediment contact is achieved by combining torque polarity transformation and change rate threshold filtering, and the defects of dependence on visual monitoring and preset lowering depth are overcome; the system is composed of a PLC master controller, a frequency converter drive, a motor hoisting mechanism, an encoder position detection and a man-machine interaction interface, high-speed data communication and accurate control are achieved through a DP network, and safe operation of equipment is guaranteed by adopting a multi-stage safety protection mechanism; the sediment grabbing precision and efficiency are improved, equipment abrasion is reduced, unattended continuous operation is achieved, and the sediment grabbing device adapts to the complex underwater environment and has good practical value and popularization prospects.

The invention discloses a silica powder modified paperboard material of embossed frame paper for cigarettes and a preparation method of the silica powder modified paperboard material, and belongs to the field of advanced inorganic non-metallic materials. The material comprises bleached chemical wood pulp, core-shell structure in-situ modified nano silicon micropowder, an auxiliary agent and a latent temperature-sensitive cross-linking agent, a modification system contains a compound silane coupling agent and amino modified organosilane, and a dual network of static triple cross-linking and dynamic secondary cross-linking is formed; the nanometer silicon micro powder is of a core-micro-nano protrusion-shell multilevel structure, a shell layer is thermoplastic resin containing latent epoxy groups, and a double-peak particle size distribution design is adopted. The preparation process is realized through in-situ generation modification, high-speed shearing fusion and an embossing-shaping integrated closed-loop control process, and is adaptive to an existing fourdrinier papermaking production line. The product quantification is 210-220 g / m < 2 >, the transverse stiffness is larger than or equal to 210 mN.m, the embossing retention rate is larger than or equal to 99.5%, after 50 cycles at the temperature of-5 DEG C-40 DEG C and the humidity of 30%-80%, the stiffness is reduced by smaller than or equal to 3%, the barrier property is reduced by smaller than or equal to 6%, the printing adsorption uniformity error is smaller than or equal to 3%, and the barrier property and the environmental protection property are excellent. The method solves the problems of agglomeration, embossing resilience, multi-performance contradiction, poor environmental stability and other pain points of conventional modified filler, realizes the cooperation of low quantification and high performance, conforms to the high-end and green requirements of the tobacco industry, can pass the application of strategic emerging industry priority review channels, and has a wide application prospect.

The present invention discloses a method for preparing food-grade glassine paper from edible mushroom liquid fermentation mycelium and the food-grade glassine paper, which relates to a method for preparing glassine paper using natural biological materials. The preparation method of the food-grade glassine paper is as follows: Step 1: Preparation of the base paper of edible mushroom liquid fermentation mycelium; Step 2: Preparation of the surface paper of edible mushroom liquid fermentation mycelium; Step 3: Preparation of the food-grade glassine paper. The present invention prepares the food-grade glassine paper from edible mushroom liquid fermentation mycelium, which can replace the traditional papermaking method mainly using wood as the raw material, without adding plastics and chemical coating agents, and has the advantages of environmental protection, low carbon and degradability. It is a food-grade oil-proof, moisture-proof and semi-transparent glassine paper, and has broad application prospects in various fields such as food, medicine and express labels.

The invention belongs to the technical field of papermaking wastewater treatment, and particularly relates to a dewatering device based on a papermaking process. A solid-phase feed opening and a liquid-phase feed opening are respectively formed in two sides of the dewatering cylinder; a support frame is fixedly connected to the outer wall of the middle part of the dewatering cylinder; a first base is fixedly connected to the bottom end of the supporting frame. Through an efficient solid-liquid separation technology, papermaking sludge is dewatered and convenient to recycle, the problem of traditional sludge treatment is effectively solved, the sludge enters the rotary drum, centrifugal force generated by high-speed rotation throws the sludge to the inner wall of the rotary drum to form a filter cake layer, and the sludge is pushed to a solid-phase discharge port to be discharged through the spiral conveyor. Meanwhile, waste water is thrown out to a liquid phase discharging opening, solid-liquid separation is achieved, the air flushing plate regularly cleans blockage of the solid phase discharging opening through the strong blowing effect of the pneumatic assembly, the scraping plate is combined with the rotary drum to rotate, sludge attached to the inner wall of the rotary drum is reduced, and the continuous and stable dewatering efficiency is ensured.

The utility model relates to the technical field of papermaking, in particular to a cellulose cooking device for papermaking, which comprises a cooking vessel, a feed port arranged at the top of the cooking vessel, a discharge port arranged at the bottom of the cooking vessel, a filter sieve arranged in the cooking vessel, a stirring rod arranged in the cooking vessel, and two groups of cleaning mechanisms arranged on the stirring rod, the lifting assembly is arranged on the digester; the rotating assembly is arranged at the bottom of the digester; according to the utility model, through the arrangement of the rotating assembly, the digester can be driven to turn over up and down through the rotating assembly, so that slurry can be turned over back and forth to form a good circulation capability, and through the arrangement of the lifting assembly at the top of the stirring rod and the arrangement of the cleaning mechanism on the stirring rod, when the slurry is stirred by the stirring rod, the slurry can be cleaned. The lifting assembly drives the stirring rod to move up and down, the cleaning mechanism can move back and forth along the filter sieve and the bottom of the digester, and scaling is prevented.

The invention belongs to the field of new materials, and relates to an ultrathin thermal insulation material and a preparation method thereof. Aiming at main problems of existing aerogel heat insulation products and actual requirements of related fields on efficient heat insulation products, in combination with functional characteristics of nano-porous silicon, natural plant fibers are taken as carriers, SiO2 aerogel, nano-porous silicon and other functional materials are uniformly mixed with the plant fibers, and the composite material is prepared. And an environment-friendly and degradable new product with heat preservation and heat insulation functions is obtained through a papermaking process. The heat conductivity coefficient of the obtained ultrathin heat preservation and insulation material is smaller than or equal to 0.025 W / (m.K), and a convenient method is provided for large-scale and continuous production of the low-cost ultrathin heat preservation and insulation material. The method is easy and flexible to operate, high in operability and easy to industrially popularize and apply.

The invention relates to an intelligent treatment method for papermaking wastewater, which comprises the following steps: S1, acquiring original operation data of a whole process, and preprocessing the original operation data to obtain a preprocessed multi-modal structured data stream; s2, constructing process interpretable features, and outputting a process interpretable feature matrix through feature selection and dimension reduction; s3, constructing a papermaking wastewater treatment knowledge graph; s4, constructing a wastewater analysis model, and obtaining a wastewater analysis result based on the process interpretable feature matrix; and S5, according to the wastewater analysis result and the papermaking wastewater treatment knowledge graph, utilizing causal reasoning to evaluate the causal influence of the strategy on the key result, eliminating potential high-risk and high-return schemes, then performing dynamic weighting on a plurality of candidate strategies by meta-learning, and combining operation preference to produce a final control strategy with an interpretable reason chain. The operation robustness and the result reliability of the wastewater treatment system are remarkably improved.

The utility model discloses a dewatering box for papermaking, which relates to the technical field of paper pulp dewaterer and comprises a dewaterer consisting of a concave case, a feed hopper and a material blocking device, the feed hopper is fixed at the top of one end of the concave case, the material blocking device is mounted at the other end of the concave case, a dewatering component is arranged on the inner side of the concave case, and the dewatering component is arranged on the inner side of the concave case. The dewatering assembly is used for conveying and dewatering paper pulp; the dewatering assembly comprises a dewatering box, a driving motor, a variable-diameter spiral feeding piece and an inclined flow guide piece. According to the utility model, the inclined flow deflectors are arranged, and water flow discharged from the screen holes above the central axis of the variable-diameter spiral feeding sheet flows downwards along the inclined surfaces of the inclined flow deflectors, so that the phenomenon that the water flow flowing out from the upper screen holes flows into the lower screen holes to cause the paper pulp to absorb water again can be avoided; the paper pulp dehydration efficiency and the dehydration effect are further improved.

The invention relates to the technical field of agricultural paper, in particular to double anti-mite fruit cultivating bag paper and a preparation method thereof. The preparation method comprises the following steps: pulping: respectively pulping natural-color bamboo pulp and natural-color softwood pulp, then mixing, adding water, and uniformly mixing to obtain pulp; papermaking: sequentially adding iron oxide yellow, aluminum sulfate, rosin size and a wet strength agent into the pulp, adding water for dilution, and drying after papermaking to obtain fruit cultivating bag body paper; sizing: taking oxidized cassava starch, adding water, preparing starch slurry, heating, continuously stirring until the starch is completely gelatinized, taking starch gelatinized liquid, adding neem oil, putting into a high-speed homogenizing emulsifying machine, emulsifying to obtain neem oil anti-mite emulsion, uniformly mixing the neem oil anti-mite emulsion with wax emulsion to obtain anti-mite glue liquid, immersing the fruit cultivating bag body paper into the anti-mite glue liquid, and drying to obtain the fruit cultivating bag. And taking out and drying to obtain the double anti-mite fruit cultivating bag paper. The composite material has physical barrier and long-acting anti-mite functions, and the risk of insect attack invasion is greatly reduced.

The invention discloses a preparation method and application of a flame-retardant coating, and relates to the technical field of flame-retardant coatings for special papers.The flame-retardant coating is prepared from, by weight, 80-85 parts of flame-retardant pigment and 15-20 parts of heat insulation pigment; the total weight of the components is set as M, the adhesive accounts for 8-15% M, the co-adhesive accounts for 7-9% M, the thickening agent accounts for 1-2% M, the lubricant accounts for 0.6-1% M, the water repellent agent accounts for 0.5-0.8% M, the defoaming agent accounts for 0.1-0.2% M, and the dispersing agent accounts for 0.2-0.3% M. The flame-retardant coating is designed and prepared, and the tipping base paper which can be carbonized at high temperature and does not burn is prepared by coating the surface of the tipping base paper. The preparation method is simple in process and high in operability, the defects of a direct papermaking method and an in-pulp addition method are overcome, the production efficiency and the resource utilization rate are improved, and the production cost is reduced. The flame-retardant tipping base paper is prepared by a coating method instead of a traditional in-pulp addition method, and a functional coating is selected and designed, so that the coating process flow and parameters are determined. The flame-retardant coating prepared by the invention endows tipping base paper with excellent high-temperature carbonization and non-combustion performance, and the flame safety performance of the tipping base paper is effectively improved.

The invention discloses a preparation technology of collection paper literature deacidification test paper, and belongs to the technical field of papermaking engineering. The method comprises the following steps: firstly, determining physicochemical indexes of the deacidification test paper according to ontology characteristics of precious ancient books and recent modern paper literatures, then taking saponified rosin size as an internal sizing agent, taking talcum powder as a filler, taking cationic polyacrylamide (CPAM) as a retention aid, and finally, carrying out papermaking and drying to obtain the deacidification test paper. The performance of the product prepared by the process is basically consistent with that of recent modern literature paper, the product has the capability of replacing a paper literature body to carry out lossy testing, and a more reliable, more comprehensive and more economical basis can be provided for constructing a deacidification effect evaluation system.

The invention relates to the technical field of papermaking, in particular to modified gypsum, a preparation method of the modified gypsum and application of the modified gypsum in corrugated base paper production. According to the invention, the stabilizer is added to modify the gypsum, so that the obtained modified gypsum not only has the advantage of crystal morphology, but also has obviously reduced solubility in water, and can be stable for a long time. When the modified gypsum is used for preparing corrugated base paper, the papermaking cost can be remarkably reduced under the condition that the mechanical property of paper is met.

The utility model discloses a closed gas hood for papermaking ventilation, and relates to the technical field of papermaking, the closed gas hood comprises a supporting bottom plate, the bottom surface of the supporting bottom plate is uniformly and fixedly connected with bottom cushion blocks through threads, the top surface of the supporting bottom plate is buckled with a sealing hood body, and the top surface of the sealing hood body is uniformly and fixedly provided with adjusting cylinders; a control panel is fixedly clamped to the side edge of the supporting bottom plate, side through grooves are symmetrically formed in the two side edges of the sealing cover body, a ventilation pipeline is horizontally inserted into one side edge of the supporting bottom plate and one side edge of the sealing cover body, an air channel groove is horizontally formed in the top face of the supporting bottom plate, and a supporting net plate is horizontally clamped to the top face of the inner side of the supporting bottom plate. A sealing top groove is formed in the top face of the supporting bottom plate, a control main board is fixedly connected to the inner side wall of the control panel in a clamped mode, an electric overall overturning opening structure is adopted so that feeding and discharging can be more convenient, and meanwhile various requirements for ventilation use can be met through an adjustable interval structure.

The invention discloses an acid-neutral nano PHA paperboard reinforcing agent as well as preparation and application thereof, and belongs to the technical field of papermaking chemicals. The reinforcing agent is a bio-based nano water-based emulsion, and the core of the reinforcing agent is that a stable high-positive-charge nanoparticle interface is constructed under an acid-neutral window through the synergistic effect of polyphenol and an amine polymer. The environment-friendly wet strength agent solves the potential safety hazard of the traditional wet strength agent, and does not contain free formaldehyde and epichlorohydrin. The method has the outstanding advantages that the method is completely compatible with a modern papermaking acid-neutral process, and the defect that the similar bio-based technology needs to react under alkalinity is overcome; the adhesive is flexible to apply, can be efficiently used for wet end addition, or can be stably compounded with oxidized starch for surface sizing; the preparation method is simple, efficient and energy-saving, can realize excellent wet strength retention rate and dry strength improvement under the conditions of low addition amount and conventional industrial drying at 105 DEG C, and does not need extra high-temperature curing.