Abstract: The invention comprises a method for clarifying ink-laden water obtained from the recycling of paper stocks by treating said water with a conventional coagulant followed by treatment with a hydrophilic dispersion polymer. The hydrophilic dispersion flocculant of the invention is a copolymer of dimethylaminoethyl (meth)acrylate methyl chloride quat (DMAEA.multidot.MCQ) cationic monomer and (meth)acrylamide (AcAm). Following dosing with the flocculant, a floc is formed. The floc contains ink and impurities which are removed from the water process stream by means of solid liquid separation; the solid liquid separation comprising a dissolved air flotation method.

Abstract: Process for making paper and cardboard, wherein at least one nitrate or basic nitrate of a trivalent metal is used as sizing agent, so that the process wastewater, after a biological denitrification treatment, can be discharged into the environment without causing pollution problems and/or can be reused at least partially as fresh water, with great savings in consumption.

Abstract: Methods for inhibiting the deposition of organic contaminants from pulp in pulp and papermaking systems are disclosed. Albumins, globulins or blends thereof and spray-dried animal blood cells are added to the pulp or sprayed onto deposition prone surfaces of a papermaking system suffering from organic contaminants.

Abstract: Stickies derived from pulping or deinking of cellulosic material are controlled by adding to the cellulosic liquor containing the stickies an emulsion in water of cross-linked, insoluble, ionisable and swellable polymer particles.

Abstract: There is disclosed a process for separating fine solids from water in the used water recovery system of a sheet forming mill, wherein the used water recovery system includes at least one stage in which an alkaline earth metal carbonate is precipitated in the aqueous suspension constituting the used water whereby the particulate material present in the used water becomes entrained in the alkaline earth metal carbonate precipitate. By the invention it is possible to recover the water and the fine solid materials which pass through the wire mesh belt of a paper or board forming machine, and optionally recycle those recovered materials.

Abstract: In a process for making a granular material from a reject stream from a coated grade waste paper pulp stock recycling process, the pulp stock is screened so that the reject stream passes through a screen and long fibers are retained for use in making paper. Solid material in the reject stream is separated by flotation. Water is removed from the reject stream to increase its consistency to that of modelling clay. The reject stream is supplied to an agglomerator which forms uniform granules of irregular but approximately spherical shape. The granules are then dried so that the granules have a solids content greater than 95%. Apparatus for performing the process and characteristics of granular material formed by the process and apparatus are also described.

Abstract: Compositions comprising polyamine and melamine polymers in certain ratios are provided for coagulating suspended solids in wastewaters such as deinking process waters and raw waters.

Abstract: Hot melt wax compositions are described that render fibrous products such as paper, paperboard and corrugated paper containers water-resistant at room temperature, but enable such articles to be repulped and recycled when the coated articles are repulped in a heated nearly neutral to alkaline aqueous medium. The compositions comprise from about 20% to 97.5% by weight of a water-repellent wax that is a solid at 20.degree. C.; from about 2.

Abstract: A mill waste or deinking waste or other suspension containing cellulosic material and hydrophobic material is flocculated by a cationic polymeric flocculant and the flocculated material, is then aggregated by a swelling clay or other anionic colloidal material, optionally further cationic flocculant is added, and the aggregated material is then separated by belt pressing or other pressure filtration as a cake.

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: A method of producing a multi-ply paperboard product. A single aqueous recycled pulp stock which contains both heavy contaminants and lightweight contaminants is separated into three fractions, including a first fraction which contains the heavy contaminants, a second middle density fraction that contains the most desirable fibers, and a third low density fraction that contains the lightweight contaminants. The three fractions are discharged from a multi-channel head box onto a forming fabric, with the middle density fraction constituting the base ply in contact with the forming fabric, the low density fraction being the central ply and the high density fraction being the outer ply, thus forming a multiple-ply paperboard product.

Abstract: A method for the dewatering of sludges in industrial waste waters utilizing a hydrophobically-modified coagulant copolymer of diallyldimethyl ammonium chloride and quaternized dimethylaminoethyl acrylate or quaternized dimethylaminoethylmethacrylate and a flocculant.

Abstract: The invention is a process for removing color from a paper mill waste effluent containing color bodies which comprises: treating the waste effluent containing color bodies with an effective color-removing amount of a water-soluble silicon-containing copolymer coagulant prepared from diallyldimethylammonium halide and a vinyltrialkoxysilane; coagulating the color bodies present in the waste effluent; and then removing the coagulated color bodies from the waste effluent.

Abstract: Hot melt polymer/fatty acid compositions are described that render fibrous products such as paper, paperboard and corrugated paper containers water-resistant at room temperature, but enable such articles to be repulped and recycled when the coated articles are repulped in a heated nearly neutral to alkaline pH aqueous medium.

Abstract: The specification discloses an unorthodox system for manufacturing strong, light-weight and weather-resistant cellulosic composite materials from discarded paper and newsprint, and papermill sludge--and from an unlimited variety of particulated fibrous lignocellulosics--without the use of an extrinsic adhesive. Both the matrix-forming resin and the fiber-substrate, which comprise the entire composite, are spontaneously created in situ at ambient conditions by the ammoniation of a mixture of a protein-containing material and a particulated cellulosic. Heating an article shaped from such a mixture to above 175.degree. C. polymerizes the resin and bonds the fiber-substrate into a cellulosic composite product. Also disclosed is a process for manufacturing reinforced and laminated composites as well as a composition which simplifies the production of both cellulosic composites and all-biomass thermosetting resins.

Abstract: A composition of paper comprising 99 to 10 weight percent cellulose fibers and 1 to 90 weight percent cored cellulose fibers that are uniformly dispersed within the paper. The cored cellulose fibers are composed of a cellulose sheath that is 4 to 15 weight percent of the weight of the fiber and a cellulose acetate core. The cored cellulose fibers contain no substantial crimp and have an average length of 1 to 7 mm, a density of 1.20 to about 1.35 gm/cc, a denier 1 to 30 grams per 9,000 meters and a uniform dispersion index of less than 0.15.

Abstract: The invention relates to a process and an apparatus for recycling backwater in a papermaking machine. According to the invention backwater draining through a forming fabric is collected into several collecting means (51, 52, 53, 54) and pumped by separate pumps (20) in at least two and preferably numerous separate flows (81 to 85) directly as substantially air free separate flows to the fibre process (12, 30, 40) of the short circulation in order to implement a fast, air free and split recycling of backwater from said forming fabric to said fibre process.

Abstract: Secondary sludge produced in the papermaking process is dewatered by adding a material capable of absorbing water together with dry fibers to the secondary sludge, and mixing the secondary sludge with the dried fibers to produce a modified secondary sludge which has sufficient structure and low enough moisture that it may be further dewatered by mechanical means. The preferred fiber adding materials are those readily produced in the papermaking process, particularly dry primary sludge, dried fines and bark and fly ash from boilers.

Abstract: There is disclosed a process for separating fine solids from water in the used water recovery system of a sheet forming mill, wherein the used water recovery system includes at least one stage in which an alkaline earth metal carbonate is precipitated in the aqueous suspension constituting the used water whereby the particulate material present in the used water becomes entrained in the alkaline earth metal carbonate precipitate. By the invention it is possible to recover the water and the fine solid materials which pass through the wire mesh belt of a paper or board forming machine, and optionally recycle those recovered materials.

Abstract: A method of integrating bleaching and recovery in connection with the production of chemical pulp that has been digested and preferably delignified with oxygen gas using processes that retain the viscosity and strength, to kappa number less than 16 without the use of chemicals containing chlorine, and using a bleaching sequence including at least one step with sequestering agent and/or acid, and a peroxide step.

Abstract: A process and an apparatus for recovering clay and fiber from papermaking sludge. The sludge is dried, milled, and separated into distinct clay and fiber components. The fiber component of the sludge is then used as an alternative fuel source. The clay component can be used as recycle into the papermaking process, a masonry additive, or for any other suitable purpose.

Abstract: Potassium permanganate is added to paper mill wastewater streams at an elevated temperature to remove color compounds from the effluent streams. The potassium permanganate causes the formation of flocculant particles which are precipitated out of the stream. This precipitate is then treated with acid to cause resolubilization.

Abstract: An improved duplex linerboard is formed from old corrugated containers (OCC) by first repulping the OCC and screening it to provide a fine fraction and a coarse fraction. NaHSO.sub.3 or H.sub.2 O.sub.2 is applied to the fine fraction and the fine fraction produce a chemically treated fine fraction which is then refined. Coarse fraction is separately refined and the refined coarse fraction pulp is then used to form the bottom ply of a multi-ply board and the refined fine fraction pulp used to form the top ply of the multiply board.

Abstract: A process for improving the freeness of paper pulp, which comprises the steps of adding to the pulp at least 0.05%, based on the dry weight of the pulp, of a cellulolytic enzyme, allowing the pulp to contact the cellulolytic enzyme for from about 40 minutes to about 60 minutes at a temperature of at least 40.degree. C., adding at least 0.011%, based on the dry weight of the pulp, of a water soluble cationic polymer, adding at least 0.007%, based on the dry weight of the pulp, of a water soluble anionic or nonionic polymer and forming the thus treated pulp into paper.

Abstract: Deinking by-product from wastepaper recycling operations and pulp mill clarifier sludge are incorporated into drywall or other gypsum-based building products, such as building blocks. The deinking by-product or pulp mill clarifier sludge is diluted and mixed with stucco (calcium sulfate hemihydrate). The resulting slurry preferably is subjected to an initial dewatering, following the on-set of hardening of the gypsum, and drywall or other building product is formed from the dewatered material. A significant loading of fibrous material in the drywall sheet or other gypsum product is achieved using the procedure, imparting improved flexural strength to the product. The preferred procedure also may be used to incorporate virgin or recycled wood pulp into the building product.

Abstract: In a process for the recovery and re-use of raw materials from paper mill waste sludge, the sludge is subjected to a preliminary cleaning treatment at a relatively low consistency, thickened to a consistency of 10 to 30%, heated to at least 100.degree. C. and then passed through a disperser in the thickened heated state before being passed to a papermachine for re-use. Papermaking fibre from at least one other source is mixed with the sludge before and/or after treatment as just described, so that the final paper product typically contains up to 30% of raw materials recovered from sludge. The action of the disperser is to break up dirt and other debris, and as a result, the recovered raw materials can be re-used in the manufacture of high quality fine papers.

Abstract: A repulpable wet strength paperboard formed from an aqueous dispersion of cellulosic fibers treated with a temporary cationic wet strength agent and a permanent wet strength agent or a reactive internal size wherein said temporary wet strength agent and said permanent wet strength agent or size are used in combined amounts sufficient to impart wet strength to said paper yet render said paper readily repulpable.

Abstract: White water from a paper machine is treated in an improved fiber recovery process, i.e., the "save-all" process. Prior to the mixing of sweetener stock into the white water the sweetener stock is fractionated (undiluted) into fine and coarse fiber fractions, of which only the coarse fraction is fed as sweetener stock into the white water. The inlet line for the sweetener stock is provided with a fractionation apparatus for removing the fine fraction from the sweetener stock. Treatment apparatus may also be utilized to separate the white water into fine and coarse fractions before passing the fine fraction to a mixer for mixing with the sweetener stock coarse fraction.

Abstract: The invention comprises a process for removing true and apparent color from pulp and paper waste waters. It comprises treating these waste waters with a coagulant and vinylamine polymer. The coagulant is selected from the group consisting of epichlorohydrin-dimethylamine, guanidine-formaldehyde condensation polymers, cyanoguanidine-formaldehyde condensation polymers, urea-formaldehyde condensation polymers, polyethyleneimines, polydiallyldimethylammonium chloride, copolymers of polydiallyldimethylammonium chloride and acrylamide, and ethylenedichloride-ammonia. The vinylamine polymer includes from about 1 to about 100 mole percent vinylamine and from about 1 to about 99 mole percent of at least one monomer selected from the group consisting of amidine vinylformamide, vinyl alcohol, vinyl acetate, vinyl pyrrolidinone and the esters, amides, nitriles and salts of acrylic acid and methacrylic acid.

Abstract: A method for removing color from a paper mill waste effluent which comprises the step of adding a low molecular weight hydrophobic polymer dispersion to the effluent. The hydrophobic dispersion is preferably formed from the precipitation polymerization of at least one hydrophilic monomer and a hydrophobic monomer in the presence of a precipitation aid, water, a chain transfer agent, and an initiator.

Abstract: A system for recovering fiber from sludge by-products generated in a pulp and paper mill. Initially, heavy materials are separated from a sludge flow, with the flow thereafter separated into first and second components. High grade fiber is recovered from the first component by centrifugal cleaners and also by optional fine pressure screens. The second component is forwarded to a refiner which breaks-down the second component to form a low grade pulp. In addition, after removal of the high grade fiber, remnants from the first component flow are forwarded to an additional separator such as a liquid cyclone, which removes sand, grit and ash, and thereafter the remnants of the first component can be sent to the refiner for forming a low grade pulp. Thus, the sludge is essentially separated into four components including: (1) high grade pulp; (2) low grade pulp; (3) heavy materials; and (4) sand, grit and ash.

Abstract: A papermaking water system utilizing vacuum pump sealing water and having a zero sealing water discharge. A group of water seal vacuum pumps are used in a papermaking machine to generate subatmospheric pressure in suction equipment and thereby extract water from a wet paper web. During operation of the vacuum pumps, the sealing water is heated and the heated water is discharged to a cooling tower to cool the water which is then recirculated to the vacuum pumps. Steam from a generating plant is supplied to the dryer drums in the dryer section of the papermaking machine, and the steam condensate is combined with the heated sealing water flowing to the cooling tower. By using steam condensate as makeup water, no ionic buildup will occur in the closed system, and high quality water is withdrawn from the closed system and may be used in other sections of the papermaking machine, so that there is no discharge of sealing water to the sewer system.

Abstract: Adhesive contaminants in secondary fiber paper pulps are detackified by the use of a water soluble terphthalate glycol terpolymer.

Abstract: A process for deinking wastepaper printed with heat fused inks to provide a source of deinked paper which can be reused or repulped and converted into a recycled paper product comprises immersing the wastepaper in a non-aqueous solvent bath containing a solvent capable of dissolving the binder component of the ink, and subjecting the wastepaper to low frequency ultrasound energy to separate the ink particles from the wastepaper. The separated ink particles may be collected magnetically or otherwise and the excess solvent recovered and reintroduced into the solvent bath.

Abstract: A recycled paper for electrophotography has a fine class pulp containing a fine class waste paper pulp. The fine class pulp is in a content of not less than 90% by weight based on the weight of the whole pulp. The recycled paper has a waste paper pulp content of more than 70% by weight based on the weight of the whole pulp.

Abstract: A method of treating an aqueous system is disclosed. The method may be used to treat sewage streams as well as aqueous streams in pulp and paper mill processing. The method includes the steps of adding a polymeric composition to an aqueous stream. The composition is an anionically modified acrylamide polymer in an aqueous medium. The polymer is formed by reacting an acrylamide polymer with phosphorous acid, and has at least 5 mole percent phosphonate groups based on the acrylamide content of the polymer, and has a molecular weight of at least about 40,000. the pH of the composition is adjusted to at least about 7.7.

Abstract: A method for clarifying the laser print deinking loop water in a papermaking process by using a water soluble graft copolymer having the structure: ##STR1## wherein E is the repeat unit obtained after polymerization of an .alpha.,.beta. ethylenically unsaturated compound, the molar percentage of a:b is from about 95:5 to 5:95, with the proviso that the sum of a and b equals 100%; G comprises the structure: ##STR2## wherein d is a cationic monomer, R.sub.1, R.sub.2 and R.sub.3 are the same or different and are hydrogen or a lower alkyl group having C.sub.1 to C.sub.3, F is the salt of an ammonium cation and the molar percentage of c:d is from 95:5 to 5:95 with the proviso that the sum of c and d equals 100%.

Abstract: The addition of an amine functional poly(vinyl alcohol) in a process for making recycled paper products results in improvements in both the wet and dry strength of the resultant products. The amine functional poly(vinyl alcohol) used in the process is formed by the hydrolysis of vinyl acetate/vinyl amide copolymers or vinyl acetate/allyl amine copolymers, or optionally may be formed by the reaction of poly(vinyl alcohol ) with an amino-aldehyde dialkyl acetal.

Abstract: A method is described for improving the removal of toxic resin acids and fatty acids from pulp and paper effluent and from other streams containing resins and fatty acids. The addition of an anionic material, such as albumin, gelatin, alginate or alginic acid prior to clarification with conventional or state of the art cationic coagulation clarification or retention will improve the removal of resin acids and fatty acids.

Abstract: White water from a paper machine is treated in an improved fiber recovery process, i.e., the "save-all" process. Prior to the mixing of sweetener stock into the white water the sweetener stock is fractionated (undiluted) into fine and coarse fiber fractions, of which only the coarse fraction is fed as sweetener stock into the white water. The inlet line for the sweetener stock is provided with a fractionation apparatus for removing the fine fraction from the sweetener stock. Treatment apparatus may also be utilized to separate the white water into fine and coarse fractions before passing the fine fraction to a mixer for mixing with the sweetener stock coarse fraction.

Abstract: Degradable particulate absorbent materials and processes for manufacture, wherein the absorbent materials have: i) in most forms of the invention, on the order of not more than 10% by weight inorganic solids or "fillers" and in all cases less than 30% inorganic solids by weight; ii) an open, porous, shot-like fiber structure with low bulk density on the order of not more than 30 lbs./ft..sup.3 and, preferably, in the range of 15 to 18 lbs./ft..sup.3.

Abstract: Wood-resin-containing process water or wastewater from the pulp industry is purified by adding, as flocculants, a high-molecular-weight polyethylene oxide and a water-soluble, non-ionic cellulose ether, suitably having a flocculation temperature of 35.degree.-80.degree. C. The added amount per liter of water is preferably 2-20 mg of the high-molecular-weight polyethylene oxide and preferably 5-30 mg of the non-ionic cellulose ether.

Abstract: A process for the production of a papermaking filler product from the fiber fines/clay fraction of a pulp, paper, paperboard, or deinking mill waste solids such process comprising the reaction of said solids with sufficient acid to lower and maintain a pH of less than 5.0. Such process yields improvement in the drainage characteristics of the material. Bleach can be added or the pH raised back to neutral to further improve the specific resistance and/or brightness of the material.

Abstract: A process for removing color from a pulp and paper wastewater which comprises the following steps: (a) treating the wastewater with a reducing agent which is capable of inactivating color producing functional groups of the wastewater; and (b) treating the wastewater subsequent to step (a) with a polymer which is capable of removing color from the wastewater.

Abstract: A hydrophobic polyelectrolyte copolymer which is useful in the removal of color in paper mill waste water. The copolymer preferably comprises an acrylamide and a hydrophobic monomer selected from the group consisting of quaternized dimethylaminoethylacrylates and quaternized dimethylaminoethylmethacrylates.

Abstract: A process for the preparation and use of a cleaning solution with both foaming and non foaming properties which can be used to de ink paper or clean surfaces which have been soiled either by the pulping of virgin or secondary recycled fiber or natural usage.

Abstract: In minimizing effluents from a cellulose pulp mill, liquid effluents from a bleach plant are concentrated, and then incinerated to produce a residue including sodium, sulfate, and sodium chloride. This residue is distilled with sulfuric acid to produce gaseous hydrogen chloride and remaining residue, the HCl being used in chloride dioxide production for the bleach plant, while the remaining residue is passed to the recovery loop (e.g. recovery boiler). Sulfur containing gases from the non-condensible gas system may be combusted to produce gaseous sulfur dioxide, which is then converted to sulfuric acid, to distill the residue. Where a non-chlorine bleach plant is provided, the liquid effluents may be concentrated in evaporators and then passed directly to the recovery boiler. The liquid streams in the mill are managed by a cascade principle to reserve the cleanest water for only those processes where it is needed while minimizing its use where it is not necessary.

Abstract: A process is for removal of suspended solids including resin and fatty acids from pulp mill effluents including Chemi-Thermo-Mechanical Pulp (CTMP) mill effluents. The process involves filtration of untreated or primary treated effluents through a mat of primary sludge, pulp or woodroom sludge. A sludge mat is formed on a wire screen or punched drum and the effluent to be treated is filtered through the mat. Most of the suspended solids and a part of colloidal material and dissolved solids are retained by the mat. Following the filtration stage, the sludge is dewatered and removed. A portion of the sludge is recycled to form the mat for the next filtration cycle, while the excess sludge is purged. The filtration is achieved by the application of vacuum below the filter mat or pressure over mat.

Abstract: Preservatives and oil are extracted from treated wood. For this purpose, treated wood that is intended to be discarded is comminuted, the chips are impregnated with an alkaline solution until softening of the chips and modification of the chemical state of the products to be extracted. Possibly, the chips may be treated with saturated steam at a temperature between 170.degree. C. and 210.degree. C. followed by an explosive decompression giving wood fragments. This is followed by a refining operation in a crusher permitting the grinding of the wood. The result is a substantial release of the preservatives and oil from the wood chips which are at least partly disintegrated. The chemical preservatives and the oil are collected separately from the wood chips in the aqueous phases which are produced in the impregnation, steam cooking-explosive decompression and refining steps.

Abstract: Process in manufacturing paper wherein stock is prepared using cellulose fiber material which contains calcium sulfate (gypsum). said material being disintegrated in an aqueous medium in order to form part of the stock for the paper to be produced. The characterizing feature of the process is that(a) carbonate ions and/or hydrogen carbonate ions (CO.sub.3.sup.2- or resp. HCO.sub.e.sup.- ) are supplied to the aqueous medium, and(b) the pH in the aqueous medium is adjusted to an alkaline value so that calcium carbonate precipitates and forms part of the suspension.There are overall major advantages provided by the process in the context of applying gypsum coatings on paper, inasmuch as broke can be reused in the process without any troublesome gypsum precipitation.