Abstract: In a hydrocyclone, particularly for deinking of paper pulp, a movable generally cylindrical plug is utilized to define an annular space near the accepts withdrawal conduit to effect release of obstructions should the annular space become clogged. The plug is biased by a spring, and moved against the spring pressure to enlarge the annular space automatically in response to a build up of back pressure. The plug also may be moved manually from exteriorly of the hydrocyclone housing, or may be operated by fluidic elements on a periodic basis to clean the annular space whether or not there has been a build up of back pressure. The hydrocyclone preferably is a gas sparged hydrocyclone, and recycled paper--with print on it--having a consistency of at least about 2% is treated to effect deinking.

Abstract: Dialkylated aryl sulfonic acids or salts thereof or their mixture are useful as collectors in the flotation of minerals, particularly oxide minerals. Collector compositions comprising these salts and oleic acid are particularly useful in hard water. Collector compositions comprising these salts and sulfide collectors such as xanthates are useful in flotations conducted at natural pH of the slurry.

Abstract: The present invention relates to an deinking agent used for reproduction of printed waste papers such as newspapers, magazines, leaflets and the like, and mainly contains one or more additives selected from the group comprising(a) additives made by adding one or more selected from alkylene oxides to at least one selected from dimer acids and polymer acids of higher unsaturated fatty acids having a carbon number of 16-20;(b) additives made by adding one or more selected from alkylene oxides to at least one selected from partial esters which are made of an alcohol having a carbon number of 1-18 and dimer acids and polymer acids of higher unsaturted fatty acids having a carbon number of 16-20;(c) additives made by adding one or more selected from alkylene oxides to one or more selected from dicarboxylic acids or dicarboxylic acid monoesters.

Abstract: A process for deinking wastepaper with an aqueous system, which includes:(a) contacting wastepaper with an aqueous system which contains an agent of one or more organically modified smectite-type clays; and(b) recovering deinked paper pulp from the aqueous system.

Abstract: A composition and method for deinking dry toner electrostatic printed wastepaper is disclosed. The composition comprises a combination of: (1) aliphatic petroleum distillates, (2) an alkylphenoxypoly-(ethyleneoxy) ethanol, and (3) an ethoxylated polyoxypropylene glycol.The method comprises administering a sufficient amount of this combination to a sample of electrostatic printed wastepaper for which treatment is desired.

Abstract: A process for the production of papermaking fiber or pulp from waste solids emanating from pulp and paper mills, particularly waste solids in process water streams containing fibrous solids that cannot be directly recycled by paper mill "saveall" devices, from pulp and paper mill process water streams conveyed by the sewerage system to wastewater treatment plant facilities, and from "sludge" emanating from the underflow of a primary clarifier or sedimentation basin at pulp and paper mill wastewater treatment facilities either before or after the "sludge" is thickened and dewatered.

Abstract: The removal of sticky contaminants during the production of recycled paper is accomplished utilizing a hydrocyclone froth flotation process. Paper having sticky contaminants from labels, tapes, hot melts, and other tacky substances, is reduced to a finely comminuted liquid solids suspension of about 1-4% consistency. The suspension is introduced into a first end of a vortex in a hydrocyclone, and the air is sparged radially inwardly into the suspension vortex by passing it through a porous inner wall of the hydrocyclone. Ligher weight sticky contaminants move to the center of the hydrocyclone, facilitated by the radially inward movement of the sparging air, and hydrophobic sticky contaminants attach to the air bubbles and form a foam. The foam and lightweight sticky contaminants are removed from the first end of the vortex, while the pulp which has had sticky contaminants removed therefrom is discharged from the second end of the vortex, opposite the first end.

Abstract: Method is disclosed of treatment of waste paper or the like at high temperatures in the range of 160.degree. C. to about 230.degree. C. The furnish is treated in a digester with or without added chemicals but in the presence of saturated steam. The preferred dwell times are in the range of about 1 minute to about 6 minutes. The treated furnish is then discharged from the digester, preferably, but not exclusively, by an explosive discharge.The advance in the art is in an improved de-inking effect, reduced consumption of chemicals and power. Also, some furnishes previously unsuitable for re-cycling, have been successfully processed by the method of the invention.

Abstract: A deinking composition comprising a deinking agent which is a reaction product obtained by:(a) reacting (i) a natural oil or a fat or a reaction product of a natural oil or a fat with glycerine, with (ii) a hexahydric alcohol, wherein the molar ratio of said hexahydric alcohol and glycerine moiety in said natural oil and fat is in the range of between 0.05/1-0.48/1, to obtain an ester mixture having a hydroxyl group value (OHV) of 18-220; and(b) reacting said ester mixture with ethylene oxide and propylene oxide wherein the molar ratio of ethylene oxide to propylene oxide is in the range of between 1.8 and 2.2, and the average mole number of added ethylene oxide is in the range of between 30 and 300, based on the mole number of glycerides present.

Abstract: The machinability of a papermaking composition of recycled fibers is improved by treating the fibrous composition with an enzyme preparation which acts on all or part of the cellulose fiber components, causing an improvement in the drainability of the water through the fibrous layer.

Abstract: The present invention relates to a method of removing ink from secondary fiber by contacting a pulp of said secondary fiber with an aqueous medium in the presence of a polymeric material having a glass transition temperature in the range of from about 20.degree. C. to about 70.degree. C. and a substituted polyethylene oxide to agglomerate the ink into discrete masses and separating the agglomerated ink from the pulp-containing aqueous medium.

Abstract: A deinking composition comprising a reaction product of a glyceride mixture, derived from natural oil and fat with ethylene oxide and propylene oxide. The glyceride mixture comprises 5 to 10 percent by weight of monoglycerides, 30 to 45 percent by weight of diglycerides and 50 to 70 percent by weight of triglycerides. The reaction product has a molar ratio of ethylene oxide to propylene oxide in the range of 1.8 to 2.2 and has, on average, from 30 to 80 moles of added ethylene oxide per mole of glycerides.

Abstract: A composition and method for the improved deinking of groundwood newsprint is disclosed. The composition comprises an amount, effective for the intended purpose, of: 1) an anionic surfactant, e.g., the ammonium or sodium salts of a sulfated ethoxylate derived from a 12 to 14 carbon linear primary alcohol blend, and 2) a dispersant, e.g., naphthalene-formaldehyde condensates.The method comprises administering a sufficient amount of this combined treatment to a sample of groundwood newsprint for which treatment is desired.

Abstract: A process for removing stickies and/or PCDD's and PCDF's from cellulose-containing fibers such as waste paper is provided. The process comprises contacting the fibers with supercritical or near supercritical propane for a period of time sufficient to extract a substantial portion of the stickies and/or PCDD's and PCDF's without substantially damaging the fibers. Extraction efficiencies of up to 95% for PCDD's or PCDF's and of about 70% to 95% for stickies have been achieved with the technique.

Abstract: A method for deinking recycled waste cellulosic material such as newsprint includes pulping the waste in the presence of an aqueous dispersion of a resin precursor, curable in said dispersion and curing the resin precursor during the pulping operation.

Abstract: Deinking of paper having print during the production of recycled paper is accomplished by a froth flotation process using a hydrocyclone. A finely comminuted liquid solids used paper suspension having a consistency of about 1 to 4% is introduced into a generally vertical axis vortex provided in a hydrocyclone. Air is sparged into the suspension in the vortex, by passing through a porous inner wall of the hydrocyclone, to cause ink particles to attach to the air bubbles and to rise in a foam while cellulosic pulp moves downwardly in the vortex. The foam--containing the ink particles--and the pulp are removed from the vortex in separate streams. The pulp is deaerated and the air component of the foam is removed in the cyclone. About 5-15% of the total flow of the suspension is removed with the foam in each stage, and about 95-85% with the pulp.

Abstract: In froth flotation apparatus for separating solid particle impurities from a liquid suspension stock in a flotation cell, provision is made for aerating the stock flowing through the inlet conduit leading to the cell by positioning a drum-shaped rotor having an irregular outer surface in the conduit on an axis extending transversely of the conduit, directing a supply of air against the rotor surface on the upstream side of its rotational axis, and causing the rotor to rotate at a linear speed of its outer surface which is substantially higher than the linear flow rate of the stock in the conduit so that the rotor surface breaks up the air impinging thereon into bubbles and distributes those bubbles in the stock flowing therepast to create foam within the cell.

Abstract: Co-polymers of diallyldimethyl ammonium chloride with up to 30 mole percent of a water soluble anionic monomer such as acrylic acid are superior coagulants for deinking process waters.

Abstract: A process for removing sticky contaminants ("stickies") from cellulose-containing fibers such as waste paper is provided. The process comprises contacting the fibers with supercritical or near supercritical carbon dioxide for a period of time sufficient to extract a substantial portion of the stickies without substantially damaging the fibers.

Abstract: A process for removing PCDD's and PCDF's from cellulose-containing fibers such as waste paper is provided. The process comprises contacting the fibers with supercritical or near supercritical carbon dioxide for a period of time sufficient to extract a substantial portion of the PCDD's and PCDF's without substantially damaging the fibers. Extraction efficiencies of greater than 95% have been achieved with the technique.

Abstract: A process for the production of papermaking fiber or pulp from waste solids emanating from pulp and paper mills, particularly waste solids in process water streams containing fibrous solids that cannot be directly recycled by paper mill "saveall" devices, from pulp and paper mill process water streams conveyed by the sewerage system to wastewater treatment plant facilities, and from "sludge" emanating from the underflow of a primary clarifier or sedimentation basin at pulp and paper mill wastewater treatment facilities either before or after the "sludge" is thickened and dewatered.

Abstract: A composition and method for inhibiting the deposition of white pitch on the surfaces of papermaking equipment during the processing of recycled coated broke. The process involves adding to the coated broke during repulping a composition having a first compound of a tetrafunctional alkoxylated diamine having the structure: ##STR1## wherein R.sub.1 and R.sub.2 are ethylene oxide or propylene oxide and R.sub.1 and R.sub.2 are not the same, and a second compound selected from the group consisting of a phosphate, phosphonate and phosphonic acid.

Abstract: A waste paper de-inking system of this invention agitates and mixes waste paper dissolving slurry and treating gas by a multi-stage type vapor-liquid mixer before a floatator treating step, separates and finely pulverizes ink and sticky matters adhered to fiber in the waste paper dissolving slurry and sufficiently absorbs and contains the treating gas in the slurry before reaching the lower most stage to facilitate de-inking operation in later floatators. Further, the high tower multi-stage vapor-liquid mixer can be utilized also as a floatator to reduce a required floor area and required power consumption of the system.Further, high temperature exhaust gas containing SO.sub.2 produced in a factory is utilized as the treating gas to perform various operations, such as desulfurization, heat recovery, bleaching and also purification of a factory environment, thereby a more economical waste paper de-inking system is provided.

Abstract: A flotation process for the de-inking of printed waste-paper by treating the paper pulp in the pulper at alkaline pH-values by means of alkali silicate, oxidative bleaches and separating the loosened printing-ink particles from the fibrous material suspension by flotation, in which protein fatty acid condensates are added finely distributed, possibly together with dispersing agents, in a solution or dispersion which is fluid at normal temperature.

Abstract: A deinking composition is used for reclamation of waste paper and comprises (a) an alkylene oxide adduct to a mixture of a natural oil or fat and a polyhydric alcohol and (b-1) an alkylene oxide adduct of a higher alcohol, (b-2) a sulfate of (b-1) or (b-3) a higher fatty acid.

Abstract: The present invention involves new anti-foam compositions which control foaming in aqueous systems and by nature of their inverse cloud point characterisitics are insoluble and particulate above their inverse cloud point, and soluble below it. This property makes them particulate non-depositing defoamers. As the defoamed aqueous system cools down these novel products become soluble, preventing insoluble material (pitch) from depositing on process equipment and matter being processed. The anitfoam composition is an alkoxylated bis-amide of the following formula: ##STR1## where R.sup.1 is ##STR2## R.sup.2 is --(CH.sub.2).sub.a --; R.sup.3 is alkyl C.sub.12 to C.sub.20 ; ##STR3## x,y,z are each independently integers from 0 to 20; a is an integer from 1 to 5;c is an integer from 0 to 5;R.sup.5 is selected from H, CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.6.

Abstract: Process for deinking printed waste paper by treatment of the paper pulp in a pulper at alkaline pH values using alkali silicate, oxidative bleaches, higher fatty and/or resinic acids and dispersants and separation of the detached printing ink particles from the fiber suspension by flotation, the fatty and/or resinic acids being used in the form of their alkaline earth metal salts in fine distribution together with dispersants in an oil-in-water dispersion which is liquid at normal temperature.

Abstract: The present invention involves new anti-foam compositions which control foaming in aqueous systems and by nature of their unique cloud point characteristics are insoluble and particulate above their inverse cloud point, and soluble below it. This property makes them particulate non-depositing defoamers. As the defoamed aqueous system cools down these novel products become soluble, preventing insoluble material (pitch) from depositing on process equipment and matter being processed.

Abstract: The present invention involves the use of a polymeric material comprised of polyvinyl alcohol moieties to control the depositing tendency of adhesive materials contained in waste paper and paper products which are being utilized to produce finished paper products. The polyvinyl alcohol is added to the water sprays or showers used on the felts, wires, and press rolls.

Abstract: An improved method for deinking waste printed, cellulosic fibrous materials which includes the addition of ionic surfactants either alone or in combination with non-ionic surfactants. The ionic surfactants are anionic, cationic or amphoteric.

Abstract: A composition containing an aqueous, recycled cellulosic fibre pulp, print pigments contaminating the pulp, from 0.1% to 10% based on the weight of the pulp solids of a curable precursor of a solid polymer resin which is not substantive to the cellulosic fibres of the pulp, and a catalyst capable of curing the resin precursor in the dispersion; wherein the resin precursor contains a mixture of a fluid prepolymer having at least two reactive functional groups per molecule and a cross-linking agent capable of reacting with the functional groups.

Abstract: A liquid absorbing pad, in particular for use in hygiene articles and sanitary products, such as diapers, bed pads, sanitary napkins, pads for incontinence, panty shields, nursing pads or the like, is produced in a dry and direct process on the basis of wet-strength and/or coated paper waste, especially originating from the production of food packages, milk carton packages, deep-freeze packages, disposable tableware and the like. The waste is cut and defibrated, and during the defibration or just before it a maximum of 25% by volume, based on the volume of the paper waste, of a mixture of water and a surfactant is added to reestablish the absorption capacity of the fibres. Starting materials otherwise difficult to process can thus be used in a dry and direct process.

Abstract: The invention is directed to the use of polyvinyl alcohol to control the problem of "stickies" in waste paper processing.

Abstract: Process for improving the quality of deinked papermaking pulps obtained by ecycling waste printed papers, in which:the papers are converted into a slush pulp (1),most of the ink (12) is removed (11) from this slush pulp, especially by selective primary flotation of the ink, andthe deinked pulp is washed (5) to remove the residual ink before being conveyed into the circuit (14) for utilization of the pulp,wherein the waters (24) from this washing (5) are first of all subjected to a selective secondary flotation (16) to remove (17) only the residual ink therefrom, the suspension of the remaining matter (fibers and fillers) (18-23) being subsequently mixed with the pulp (15) originating from the washing (5).The invention also relates to a plant for making use of this process.

Abstract: The present invention relates to a method of removing ink from secondary fiber by contacting a pulp of said secondary fiber with an aqueous medium in the presence of a polymeric material having a glass transition temperature in the range of from about 20.degree. C. to about 70.degree. C. and a substituted polyethylene oxide to agglomerate the ink into discrete masses and separating the agglomerated ink from the pulp-containing aqueous medium.

Abstract: A method and apparatus for decomposing waste paper in a storage tank (tower) under the effect of chemicals with a high stock concentration (high-consistency stock method), including the rotation of the paper pulp together with dilution and a vigorous extensive disintegration of the waste paper or rags by a slushing rotor in the lowest part of the storage tank (tower).

Abstract: The instant invention is directed to a method for deinking cellulosic fibrous material impregnated with ink wherein a mixture of said material and water is stirred in the presence of a deinking agent, the improvement wherein the deinking agent is a hydrolyzed copolymer of dimethyldiallyl ammonium chloride and acrylamide.

Abstract: The present invention involves the use of a methyl cellulose derivative to control the depositing tendency of adhesive materials contained in waste paper and paper products which are being utilized to produce finished paper products.

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.

Abstract: An apparatus for improving the quality of paper manufactured from a contaminated fibrous stock having therein recycled paper pulp and contaminants smaller than a predetermined size and with a specific gravity approximately that of the specific gravity of whitewater used in the production of recycled paper stock comprises a hydrokinetic amplifier having a mixing chamber connected to each of a steam inlet, a stock inlet, a chemical feed inlet, an overflow discharge and a venturi. The venturi is connected to an outlet of the hydrokinetic amplifier. The apparatus also includes a pulper, a dump chest, a cyclone separator, a pressure screen, a vibratory screen, a holding tank, a pump, and various auxiliary pumps, valves, piping and sources of steam and whitewater.

Abstract: Waste paper fibers containing tacky impurities processed for the preparation of recycle paper fiber products in the presence of a surface-active tertiary amine or tertiary or quaternary ammonium compound, thereby reducing discoloration and tackiness.

Abstract: The present invention involves the use of a methyl cellulose derivative to control the depositing tendency of adhesive materials contained in waste paper and paper products which are being utilized to produce finished paper products.

Abstract: Ink-bearing secondary fiber feedstocks are mechanically fiberized in a substantially dry state to produce substantially discrete fibers and ink-bearing fines, and the fibers are separated from the fines in a substantially dry state.

Abstract: A process for the deinking of waste newsprint, which comprises steps for(a) converting the waste newsprint to a pulp,(b) contacting and agitating the pulp in an aqueous medium containing a deinking agent comprising a mixture of (i) a water-soluble C.sub.9 to C.sub.16 alkanol ethoxylate component having an average of about 6.5 to 20 oxyethylene units per ethoxylate molecule and (ii) an oil-soluble C.sub.9 to C.sub.16 alkanol ethoxylate component having an average of about 0.5 to 3.5 oxyethylene units per ethoxylate molecule, said mixture containing the respective components (i) and (ii) in a relative weight ratio in the range from about 2:1 to 1:3, and said mixture being present in said aqueous medium in an amount between about 0.1 and 5 percent by weight based on the dry weight of the newsprint fiber, and(c) recovering deinked pulp from the aqueous medium.The invention offers high performance in the removal of ink from pulp fibers and substantially eliminates the foaming of aqueous surfactant solution.

Abstract: This invention relates to microbicidal/microbistatic compositions for industrial use which comprise 4,5-dichloro-1,2-dithiol-3-one and a haloacetic acid ester and an industrial method of killing and/or inhibiting microbes by using the aforementioned compositions.

Abstract: The method of substantially removing and dispersing resinous or waxy contaminants from contaminant-containing secondary fiber during repulping, is disclosed. The method includes combining the contaminant-containing secondary fiber in an aqueous repulping medium with a substituted oxyethylene glycol nonionic surfactant, and a water soluble, low molecular weight polyelectrolyte dispersant, at an elevated temperature.

Abstract: A method for the deinking of wastepaper which comprises converting the wastepaper to a pulp, contacting the pulp with an aqueous medium of alkaline pH containing between about 0.2 and 2 percent by weight, calculated on dry weight of the pulp, of a deinking agent which is one or a mixture of certain thiol ethoxylate compounds, and treating the resulting pulp-containing medium to remove suspended or dispersed ink. The use of a thiol ethoxylate deinking agent offers a high level of performance in such a deinking process, both from the standpoint of the overall brightness and dirt count of paper prepared from the deinked pulp. In certain specific embodiments, the invention further comprises a step for treating thiol ethoxylate containing process streams and effluents to convert the surface active deinking agent to low-foaming sulfonyl derivatives, or to degrade the deinking agent to non-surface-active matter.

Abstract: There is disclosed an improvement to the process for the de-inking of printed waste paper which comprises (1) treating the waste paper in a pulper at an alkaline pH with alkali silicate, an oxidatively active bleaching agent, one or more acid components selected from the group consisting of fatty acids and resinic acids containing more than 10 carbon atoms, and mixtures thereof, and a dispersing agent, and (2) separating the detached printing ink particles from the fiber suspension by either flotation, washing, or a combination thereof. The improvement comprises employing the acid and the dispersing agent in the form of an oil-in-water emulsion.

Abstract: The invention relates to a method of treating waste paper, wherein the waste paper is steeped, under certain circumstances chemically treated at the same time, and is thereafter adjusted to a lower substance density and sorted. Furthermore, the invention relates to apparatus for performing such a method.

Abstract: A process for the deinking of xerographically printed wastepaper to produce reclaimed stock having high brightness and low dirt count. The process centers upon contact between a wastepaper pulp and an aqueous medium of alkaline pH containing a deinking agent consisting of a mixture of one or more C.sub.5 to C.sub.20 alkanols with nonionic surfactant to form a suspension of the ink in the aqueous medium. The deinking agent suitable for practice of the invention necessarily contains for every 10 parts by weight between 3 and 5 parts of alkanol and between 5 and 7 parts of nonionic surfactant, and is present in the aqueous medium in an amount between about 0.2 and 2.0 percent by weight, calculated on the dry weight of the pulp.