Abstract: Methods and apparatus are provided for exploiting coated paper products such as coated paper cups. End products include biofuels that have a high energy density. The biofuels may be mixed with coal or other fuels and have good binding characteristics. In some embodiments, useful chemicals such as HMF are produced. The methods involve heat treatment at relatively mild temperatures and pressures under acidic conditions.

Abstract: The method increases the yield and improves the beatability of kraft pulp. During the progression of the cooking process, more than one cooking liquor with a dissolved content of hemicellulose is drawn off and then reintroduced to the last phases of the cooking process, to re-precipitate the hemicellulose on the fibers. The hemicellulose rich cooking liquors are adjusted so that they, upon being added to the last phase of the cooking process are optimized. Early dissolved hemicellulose has a longer chain length than the hemicellulose that dissolves in the cooking liquor in the later phases of the cooking process, and they also have different tendencies to precipitate on the wood chips softened in the cooking process.

Abstract: Methods and apparatus are provided for exploiting coated paper products such as coated paper cups. End products include biofuels that have a high energy density. The biofuels may be mixed with coal or other fuels and have good binding characteristics. In some embodiments, useful chemicals such as HMF are produced. The methods involve heat treatment at relatively mild temperatures and pressures under acidic conditions.

Abstract: Disclosed is an open flotation de-inking module for recycled paper comprised of a flotation cell having an injector module and air control module used in conjunction to infuse micro air bubbles into pulp slurry to optimize the process of separating ink, clay, stickies and other float able contaminants from the recycled pulp slurry by negatively pressurizing the slurry as it accelerates through the injector drawing air from the air control module saturating the slurry with air bubbles before injection into the flotation cell whereupon the contaminants will adhere to the bubbles as they move to the surface forming a foam that is passively skimmed into reject compartments with the decontaminated pulp channeled from the floatation cell for further processing.

Abstract: Disclosed is a closed floatation conventional de-inking process adopted in the recycled paper processing plants, in which, ink separation and removal constitutes a major task. The specific concerns of this invention are the concept and the equipment for the separation and removal of the ink and ash from the pulp slurry contaminated with ink, clay and stickies.

Abstract: A method of treating solid containing material derived from effluent or sludge from a plant for deinking paper, the material containing calcium in the form of one or more insoluble calcium compounds, the method including the steps of treating the material with an acid to cause dissolution of the calcium thereby forming a calcium ion-containing solution in which insoluble solids are suspended, separating the solution from the insoluble solids and incinerating the separated solids. The solution containing calcium ions may be treated by adding one or more reagents to form a calcium compound precipitate, eg calcium carbonate. The particulate solids produced following the incineration step and following the precipitate formation may be employed as pigments or fillers in paper making or paper coating.

Abstract: A method for brightening virgin mechanical pulp. The method comprises combining: (i) an aqueous solution comprising sodium borohydride and sodium hydroxide; and (ii) an aqueous solution comprising sodium bisulfite, in a chemical mixer and adding output of the chemical mixer to an aqueous slurry of virgin mechanical pulp. The ratio of (moles bisulfite?moles hydroxide)/moles borohydride is from 0 to 7.8.

Abstract: A process for producing high bulk cellulosic fiber exhibiting a durable elevated curl index includes: (a) concurrently heat treating and convolving cellulosic fiber pulp at elevated temperature and pressure at high consistency under conditions selected so as to preclude substantial fibrillation and attendant paper strength and fiber bonding development; and (b) recovering the pulp wherein the length weighted curl index of the treated fiber is at least about 20% higher than the length weighted curl index of the fiber prior to the heat treatment and convolving thereof. The curl imparted to the fiber persists upon treatment for 30 minutes in a laboratory disintegrator at 3000 rpm at 1% consistency at a temperature of 125° F. Moreover, the curl may be imparted to the fiber in a disk refiner at very short residence times, on the order of several seconds or less. In general, the process is carried out in the presence of saturated steam at a pressure of from about 5 to about 150 psig.

Abstract: A method for bleaching and color stripping recycled fibers by treating the fibers with a mixture of sodium borohydride and sodium bisulfite.

Abstract: A process for bleaching substantially lignin-free pulp or paper in a single-stage bleaching process or multi-stage bleaching process; comprising

Abstract: Disclosed is a method for pulp bleaching. The method comprises the steps of providing a pulp sample for bleaching, the pulp sample stemming from a pulp producing process, providing a bleaching liquor comprising water and an organic component as solvent components constituting a bleaching medium, dissolved within are at least a bleaching agent, and a basic agent; and subjecting the pulp sample to the bleaching liquor for a predefined amount of time at predefined bleaching conditions. A preferred bleaching agent is hydrogen peroxide. The organic component amounts to at least 5% in weight of the bleaching medium.

Abstract: A method of treating solid containing material derived from effluent or sludge from a plant for de-inking paper, the material containing calcium in the form of one or more insoluble calcium compounds, the method including the steps of treating the material with an acid to cause dissolution of the calcium thereby forming a calcium ion-containing solution in which insoluble solids are suspended, separating the solution from the insoluble solids and incinerating the separated solids. The solution containing calcium ions may be treated by adding one or more reagents to form a calcium compound precipitate, e.g., calcium carbonate. The particulate solids produced following the incineration step and following the precipitate formation may be employed as pigments or fillers in paper making or paper coating.

Abstract: A process for making a pulp product that has a low COD is comprised of soaking and washing pulp in alkaline water for a sufficient time so that the COD after soaking and washing is less than or equal to 2.0 kg/1000 kg of dry pulp. The process includes repetitively soaking and washing an unbleached pulp in alkaline water that is never allowed to drop below pH 7.0. In this process, the pulp is soaked and washed for a total of at least 220 minutes at an elevated temperature to produce the pulp product that has a low COD.

Abstract: A process for bleaching substantially lignin-free pulp or paper in a single-stage bleaching process or multi-stage bleaching process; comprising

Abstract: Materials for use in forming composite products are prepared from recycled composite materials and treated by hydrothermal treatment at 40 ° C. to 120 ° C. along with or followed by high shear treatment. The process enables the use of recycled materials not hitherto usable successfully and it is possible to form composite products with less or no additional bonding resin.

Abstract: A method for removing wax from a pulp furnish is disclosed. The method is effective for removing wax from a pulp furnish containing waxed old corrugated containers (OCC). In the method, the pulp furnish containing waxed OCC is treated with an agglomeration chemical which separates wax from the fibers and agglomerates the wax for removal by screening. In a preferred embodiment, the pulp furnish is treated with a caustic material to enhance wax removal.

Abstract: An improved process for the separation of cellulosic fiber from difficult to process coated and inked paper products is disclosed and claimed. This process readily separates the paper pulp fraction substantially free of contaminants from such waste paper products as single and two side polymeric coated board having wet strength resin, single and two side polymeric coated board having no wet strength resin, single and two-sided glossy printer trimmings, ultraviolet (UV) cured ink coated stocks, and mixtures thereof. Preferred embodiments include a process in an inclined pressure vessel equipped with agitating and rotating means operative to reflux the waste material with respect to the inclined axis of the vessel in the presence of steam and chemical aids for a sufficient period of time so as to bring about repulping and separation of the paper fiber fraction and formation of a contaminant-collecting polymer phase.

Abstract: Disclosed is a process for preparing a paper web. The paper web is prepared from a low-grade furnish, which contains low-grade pulps, such as recycled pulp and/or groundwood pulp, and which, in one preferred embodiment, is a newsprint furnish. In accordance with the disclosed process, a pre-flocculated filler is added to the furnish prior to forming the paper web from the furnish. Filler will be retained in the web, and retention of undesired components of the furnish in the web will be reduced as compared with newsprint in which a filler is incorporated via conventional processes. Another embodiment contemplates the incorporation of a pre-flocculated coated broke slurry into a paper furnish prior to paper formation. The paper web formed via the process of the invention will have improved properties as a result of the incorporation of the pre-flocculated filler or treated broke into the web.

Abstract: A method of treating wood-fiber pump, particularly wood-fiber pulp that contains recycled paper, comprises delivering the pulp to and advancing the pulp in a heating zone while delivering steam to the heating zone. The pulp is finely-divided in a disperser and the finely-divided pulp delivered to a screw press without separate departure of steam, so as to compact the pulp in the end of the screw press and therewith form a plug seal. At the same time, one or more bleaching chemicals is or are supplied during one or more treatment stages, and the temperature of the pulp is regulated to obtain an optimal bleaching process or optimal bleaching processes. The temperature of the pulp can be raised or lowered by supplying steam or water thereto respectively. The invention also relates to a plant for carrying out the method.

Abstract: Disclosed is a process for preparing a paper web. The paper web is prepared from a low-grade furnish, which contains low-grade pulps, such as recycled pulp and/or groundwood pulp, and which, in one preferred embodiment, is a newsprint furnish. In accordance with the disclosed process, a pre-flocculated filler is added to the furnish prior to forming the paper web from the furnish. Filler will be retained in the web, and retention of undesired components of the furnish in the web will be reduced as compared with newsprint in which a filler is incorporated via conventional processes. Another embodiment contemplates the incorporation of a pre-flocculated coated broke slurry into a paper furnish prior to paper formation. The paper web formed via the process of the invention will have improved properties as a result of the incorporation of the pre-flocculated filler or treated broke into the web.

Abstract: A repulpable wax containing paper product consists essentially of a hot melt formulation with an effective amount of an inorganic mineral filler such as clay. The inorganic mineral filler is in an amount which permits the article coated with the hot melt—inorganic mineral filler formulation to be repulped and recycled.

Abstract: A non-woven web such as a facer comprises recycled cellulose fiber; recycled glass fiber, and, a sizing agent which provides the mat with decreased liquid penetrability over time. An example suitable sizing agent is alkenyl succinic anhydride (ASA) which has a dry basis add-on rate of from about 0.15% to about 0.4%, and preferably a dry basis add-on rate of from about 0.2% to about 0.3%. The sizing agent provides the mat with decreased liquid penetrability four weeks after mat production. In one aspect of the invention, the mats/facers can be employed as a facer for a rigid cellular foam board.

Abstract: The present invention relates to a process and composition for the recovery of fibre from waste paper and paper broke which has been treated with wet-strength resins. Specifically the present invention is directed to the removal of such resins from the fibre material, so that such fibre material may be recycled to a paper web forming process, by using selected persulfates such as potassium persulfate. Optionally, the persulfate is used in combination with a surfactant. Improved repulping of the waste paper is achieved.

Abstract: A process for the manufacture of recycled paper having improved strength properties is achieved by replacing refiners by agitators, modifying extractor, applying effective amount of dispersion aids, and applying appropriate amount of dry strength additives.

Abstract: A method for repulping a wet strength paper is disclosed. Wet strength paper, which contains a wet strength resin, is agitated in water to form an aqueous slurry. An effective amount of a composition that contains a dry mixture of a persulfate and a base in the range of 90:10 to 10:90 is added either before or during agitation, and the slurry heated to produce pulp product for paper manufacture. The persulfate/base combination is capable of breaking down the wet strength resin and adjusting or maintaining the pH at a predetermined level without additional chemical treatment.

Abstract: A process of repulping paper a product comprising cellulose fibers, comprising forming an aqueous suspension of paper product to be repulped and an oxidizing agent comprising at least one persulfate salt, and maintaining the pH of the aqueous suspension in a range of from about 2.3 to about 6.5. The process is preferably conducted in the presence of preferred buffer systems. Compositions for conducting such processes are also provided.

Abstract: This invention is a method for deinking wastepaper by disintegrating the waste paper in an carbonate aqueous solution containing sodium sulfite and sodium carbonate to produce a fibrous slurry having a pH of at least 7.5, separating the ink from the fibers and removing the ink from the slurry. A composition useful for deinking fiber consists of a relative proportion of sodium sulfite to sodium carbonate between about 95:5 and about 50:50, and a surfactant.

Abstract: Repulping and/or decolorizing formulations and mixtures which include a catalytic amount of a salt of a metal such as copper, iron, silver, or nickel; a persulfate; and from 0-10% saccharide. Formulations containing a carbonate, sesquicarbonate or bicarbonate for adjusting pH are preferred. A method of repulping and/or decolorizing broke, whether containing wet strength resin or not, using the formulations or mixtures of the ingredients in the formulations.

Abstract: A method of bleaching recycled paper containing pulp wherein said pulp is contacted with ozone in an ozone stage (Z) treatment with a brightness stabilizing step during or at the end of said ozone stage (Z), said stabilizing step consisting of contacting a small amount of hydrogen peroxide with said pulp, the amount of hydrogen peroxide contacted with said pulp being small compared to the amount of hydrogen peroxide usually in an hydrogen peroxide stage, no washing step of the pulp being provided between the ozone contacting step with said pulp and the hydrogen peroxide contacting step. The pulp is first submitted to a test procedure to determine whether the pulp is more reactive to ozone in acidic or alkaline conditions, and if necessary the pH is accordingly adjusted.

Abstract: The invention relates to a method for decolorizing paper pulp containing colored fibers. The paper is first pulped and subjected to fine screening. The screened pulp is then dispersed at a temperature in excess of 100.degree. C. and a pressure exceeding one atmosphere absolute pressure. Prior to the dispersing step a first agent (a reducing agent or oxidizing agent) is introduced to the pulp. A second agent is introduced to said pulp after introduction of the first agent. The second agent is an oxidizing agent when the first agent is a reducing agent, and a reducing agent when the first agent is an oxidizing agent. Finally, the dispersed pulp is recovered after the colored fibers are decolorized.

Abstract: A composition containing a persulfate and a carbonate, a bicarbonate or sesquicarbonate, which composition is suitable for oxidizing wet strength resin based broke used in wet strength paper. The combination decreases the time required for effectively repulping broke from such paper. Additionally, the combination is a single product capable of beaking down the wet strength resin and adjusting or maintaining pH at a predetermined value without additional chemical treatment.

Abstract: The present invention aims at preventing or reducing the lowering in mechanical characteristics of a carbon fiber reinforced carbon composite due to stress orientation caused by the use of a thermosetting resin as a carbon matrix precursor resin to thereby obtain a carbon fiber reinforced carbon composite improved in mechanical characteristics, and for attaining this aim, provides a process for the preparation of a carbon fiber reinforced carbon composite which comprises impregnating a carbon fiber with a bismaleimide-triazine copolymer resin instead of the sizing agent and thermoplastic resin which have been used conventionally and heating the resulting impregnated carbon fiber in a non-oxidizing atmosphere to carbonize or graphitize the resin.

Abstract: Paper and paperboard can be effectively repulped by a composition of nonchlorinated oxidizing agent (persulfates) and a buffer (carbonates) yielding a pH of 7-12. The repulping composition of the present invention is particularly useful in repulping paper containing wet strength resins.

Abstract: The present invention discloses a process for treating filter rods comprising cellulose acetate tow waste comprising the steps of:a. cutting said filter rods so that fiber of said cellulose acetate have a fiber length of less than about 4 inches; andb. treating said cut filter rods with an aqueous base until at least 5% of acetyl groups on said cellulose acetate has been hydrolyzed.Filter rods treated in this manner are suitable for use in various paper products. The process of the present invention may further include a step for repulping the cut filter rods to repulp any included plugwrap.Modified fiber comprising cellulose acetate wherein at least 5% of acetyl groups on said cellulose acetate have been hydrolyzed, said fiber having a length of less than about 4 inches, are also disclosed.Paper products comprising between about 5 and about 90% of the fiber of claim 21 and paper pulp are also disclosed.

Abstract: Process for repulping wet strength paper containing at least one wet strength resin in which initial breakdown of the paper is conducted at a first pH and the substantial completion of the conversion to fibers is conducted at a second pH which is higher than the first pH.

Abstract: This invention relates generally to a method for extracting lignosulfonate for the manufacture of vanillin and other specialty chemicals. Specifically, the invention relates to a method for recovering lignosulfonates from newsprint comprising the steps of:a) converting newsprint to a crumb pulp comprising of from about 20% to about 50% crumb pulp fiber solids by weight on an oven dry basis and the remainder water;b) cooking the crumb pulp in a medium comprising crumb pulp and cooking acid solution selected from the group consisting of sodium bisulfite, magnesium bisulfite, ammonium bisulfite, calcium bisulfite or mixtures thereof wherein the weight ratio of cooking acid solution to the crumb pulp fiber is from about 3 to about 6 for sufficient time and sufficient temperature and pressure for lignosulfonate removal;c) separating the crumb pulp fiber from the spent sulfite liquor; andd) recovering the lignosulfonates from the spent sulfite liquor.

Abstract: A method is disclosed for producing, in a continuous throughput, high quality paper from recycled waste paper utilizing high consistency, low shear pulping, followed by a series of cleaning steps to produce a wet, friable pulp which is digested and optionally bleached. The resulting pulp can be run on a paper machine alone or blended with virgin pulp to produce a paper containing at least 5% by weight recycled paper with less than 20 ppm per unit area solid non-fibrous contaminants larger than 0.3 mm.sup.2, and which may be blade coated on a high speed paper machine. The pulp and paper produced by the methods are also disclosed.

Abstract: A method for brightening fiber from colored waste paper comprising bleaching pulp from colored waste paper with sodium hydrosulfite, formamidine sulfinic acid, or hydrogen peroxide in the presence of a selected quaternary compound.

Abstract: A method for conditioning the felts in a papermaking process utilizing deinked secondary fiber in the furnish by adding a felt conditioner consisting of from 5-33% of a nonionic surfactant, from 5-33% of a dispersant, or blends thereof, with the remainder water; wherein the nonionic surfactant is selected from the group consisting of ethoxylated nonylphenols having moles of ethoxylation of from 7.5 to 30 and an HLB of about 12 to 17.2 and di-alkyl phenol ethoxylates having moles of ethoxylation of from 15 to 24 and an HLB of about 13 to 15.1; and wherein the dispersant is selected from the group consisting of the sodium salt of naphthalene sulfonate formaldehyde-condensate having an average molecular weight of from about 700 to 3500, the potassium salt of polymerized alkyl naphthalene sulfonic acid having an average molecular weight of approximately 1000, or the sodium or ammonium salt of lignosulfonate. Additionally, from 1 to 5% of an alkylether hydroxypropyl sultaine enhances performance.

Abstract: Paper pulp, especially recycled paper pulp which has been deinked, is bleached in a synergistic two-stage process first with sodium bisulfite and then with sodium borohydride. The borohydride is preferably added in an aqueous mixture with sodium hydroxide. A weak acid such as acetic acid may be added to the pulp to advance further the brightness gain.

Abstract: A method for bleaching pulp containing pulp from color dyed waste paper, wherein the method comprises bleaching the pulp with a bleaching chemical, especially sodium hydrosulfite, in the presence of a selected ethoxylated amine.

Abstract: A method is disclosed for producing, in a continuous throughput, high quality paper from recycled waste paper utilizing high consistency, low shear pulping, followed by a series of cleaning steps to produce a wet, friable pulp which is digested and optionally bleached. The resulting pulp can be run on a paper machine alone or blended with virgin pulp to produce a paper containing at least 10% by weight recycled paper with less than 20 ppm per unit area solid non-fibrous contaminants larger than 0.3 mm.sup.2, and which may be blade coated on a high speed paper machine.

Abstract: The invention is directed to a method for deinking and uncoating printed paper which comprises using a monocomponent cellulase during recycling.

Abstract: The invention relates to a method of bleaching waste paper pulp. The pulp is first treated to a reductive chemical followed by acidification and washing or dewatering. The pulp is then subjected to ozone and then to hydrogen peroxide. The reductive chemical used is either formamidine sulphinic acid or sodium hydrosulfite.

Abstract: This invention relates to a method for producing packaging materials containing reclaimed/recycled fiber by chemically hydrolyzing the fiber, treating the fiber at elevated temperature greater than 100.degree. C., adding a reduced sulfur agent to the fiber to reduce the sulfur content of the fiber by forming insoluble heavy metal sulfide compounds which precipitate from the hydrolyzed fiber, oxidizing and then washing the fiber to produce a paper pulp. Such methods of this type, generally, produce reclaimed/recycled fiber that is sufficiently hygienic for food grade and medical device packaging applications.

Abstract: Deinked paper/wood pulps are improvedly bleached to high levels of whiteness by conjointly treating such pulps with a sulfite bleaching agent, e.g., Na.sub.2 SO.sub.3, NaHSO.sub.3 or mixture thereof, or SO.sub.2 and NaOH, and a reducing agent more electronegative than the sulfite ion, e.g., thiourea dioxide, sodium borohydride or sodium dithionite, in a reaction medium having an initial pH ranging from 6 to 12, advantageously followed by washing sulfite and reducing agent values from the bleached pulp and then treating the washed pulp with hydrogen peroxide in an aqueous alkaline medium.

Abstract: Recycled paper pulp is de-inked by pulping it at neutral or alkaline pH with an aqueous deinking composition comprising one or more reducing agents. The preferred reducing agents are sodium bisulfite and sodium borohydride. Sodium hydroxide is preferably used to give the desired pH.

Abstract: Deinked paper pulp is subjected to bleaching with sulfite or bisulfite ions and a reducing agent, preferably sodium bisulfite and sodium borohydride in aqueous alkaline solution. To assist the removal of ink particles, steam is bubbled through the pulp causing the ink particles to rise to the surface as a black foam which can be continuously removed.

Abstract: Good deinking of waste paper can be obtained at high consistency by first pulping at high pH, then lowering the pH, adding alkaline cellulase and letting the cellulase act during continued pulping and/or maceration. The improved deinking results in higher whiteness and better cleanliness (fewer ink particles) in paper made from the treated pulp after separation of ink particles. This cellulase treatment results in better operation of certain equipment such as thickeners and in better drainage of the pulp during paper making.

Abstract: A waste paper recycling process relates to the treatment of a mixture of waste paper containing non-cellulosic contraries and printing inks, in order to release the contraries from the fibers and further to separate them from the stock in order to produce re-usable pulp for the production of paper and board.The invention has to do with new and useful improvements in methods for first removing the non-ink contraries from the fibrous mass and second releasing and then removing the ink particles from the said fibrous mass.The invention is directed to the treatment of the fiber slurry produced during the ink separation stage, after the ink releasing stage has been applied. One aim of the process is to allow both the use of the fibers and the mineral fillers contained in that slurry, for pulp and board making, and the use the solids-free water contained in the same slurry as the washing liquid in the previous ink-separation treatment, thus closing the fibers and the water circuits.