Abstract: The invention relates to a method and apparatus for manufacturing paper or like products which contains retention agent and inorganic filler. The retention and technical properties of the paper are enhanced by coflocculating the filler with a cellulosic material having a large specific surface area (fine pulp) prior to introducing floc suspension into the stock, and by subjecting the flocs to a floc size-controlling shearing process in a particular reaction vessel to produce flocs that have a mean particle size within the range of 2-4 mm. The particular reaction vessel used herefor incorporates a mixing zone, a flocculation zone, separator means located between the mixing zone and flocculation zone, a shearing zone and a sedimentation zone.

Abstract: Processes for treating waste paper containing aluminum and having a high lignin content are disclosed, including producing an aqueous pulp suspension of the waste paper, screening the pulp suspension, dewatering the pulp so as to produce a first white water stream including most of the aluminum, delignifying the pulp suspension with oxygen, separating a portion of the aqueous liquid from the delignified pulp to produce a separated pulp stream and a second white water stream which is substantially free of aluminum, transferring the separated pulp to a paper mill, diluting the separated pulp stream with a dilution liquid stream in the paper mill, evaporating the second white water stream, and transferring at least a major part of the first white water stream to the paper mill for use as the dilution liquid therein.

Abstract: White water at a high speed of current occurs in the region of a forming roll in a paper machine running at a high speed. The white water is caught in a white water trough which is provided with deflection vanes and is carried substantially at the initial speed by means of a duct (1) out of the ground plan of the paper machine to a stilling tower (2) standing adjacent to the paper machine, to feed the inner wall of a screen wall (3) of a screen cage, which wall is arranged in the stilling tower. The wall (3) is curved and has openings (4) for the white water to pass through. They are designed to peel off in layers the film of white water which is sent along the wall (3) and to deflect the jets of white water passing through the openings (4) radially outwards to the wall (3) against an outer wall (5) of the stilling tower (2), where the actual deceleration of the current takes place in several individual jets.

Abstract: A method of, and washing machine or washer for, washing stock suspensions, wherein a rotatable cylinder having a solid smooth surface is encircled along a portion of its circumference by a movable endless wire or filter band. The stock suspension to be dewatered and washed is infed by a flat jet nozzle between the rotatable solid cylinder and the movable endless wire. The fiber web formed between the rotatable solid cylinder and the movable endless wire has a weight of less than 100 grams per square meter, preferably 30 to 70 grams per square meter. The wire speed and the circumferential speed of the rotatable solid cylinder is in the order of about 400 to 1,200 meters per minute. After through-flow of the stock suspension between the rotatable solid cylinder and the movable endless wire, the dewatered and washed fiber material is removed from the movable endless wire and the rotatable solid cylinder, respectively, collected in a collecting container and delivered for further processing.

Abstract: Apparatus and method for the manufacture of a non-woven fibrous web such as paper from a dispersion of fibers in a foamed liquid in which fiber furnished in a foamed liquid comprising a solution of surfactant in water is discharged from a headbox into the nip of a twin forming wire prior to its passage over a forming roll. The water-surfactant solution is drained from the web and recycled as a foamed liquid containing about 65% air in the form of bubbles of from about 20 to about 200 microns in diameter. The foamed liquid is directed into a mix tank wherein a slurry containing fiber at 20% to 55% solids is added and mixed. The mixture is pumped to the headbox and into the nip of the forming wires.

Abstract: A process for making a cement and non-asbestos fiber mat on a Hatschek machine having a cylinder vat, a cylinder in the cylinder vat, and a porous surface on the cylinder on which the mat is formed and through which drainage water passes including the steps of introducing a slurry of cement and non-asbestos fibers and clay and poly(ethylene oxide) and water into the cylinder vat, and maintaining a lesser portion of the porous surface in engagement with the cement and non-asbestos slurry than the portion of the surface which is otherwise normally engaged by a cement and asbestos slurry of the same depth to thereby form the cement and non-asbestos fiber mat on the lesser portion of the porous surface and thus provide a lesser area for the slurry to drain than the area through which a cement and asbestos slurry drains, the poly(ethylene oxide) and clay causing the drainage water to be substantially clear and not to have any appreciable amount of cement fines, the cement and non-asbestos fiber mat containing Port

Abstract: Use of oxygen, oxygen containing gases or substances giving off oxygen in reduction or inhibition of the dark coloring of pulp or paper in white water systems, especially closed ones, in production of pulp and paper, these substances being added to the white water system in such an amount that aerobic conditions are maintained substantially permanently in at least a part of the white water system, i.e. the redox potential is higher than -100 mV.

Abstract: A method of treating chemical process water which contains dissolved solids, usually of a biodegradable organic nature. According to the invention, the dissolved organic solids, which are objectionable because they cause process equipment corrosion, undesirable product and process odors and pollution, are treated with ultraviolet light. The light treatment causes dissolved materials of relatively simple chemical structure to react and create more complex, less soluble materials which can easily be removed from the system as they become less soluble. The method is applicable to papermaking and numerous other industrial processes using large quantities of process water.

Abstract: Apparatus and method for the manufacture of a non-woven fibrous web such as paper from a dispersion of fibers in a foamed liquid. In a preferred embodiment, a solution of surfactant in water is initially discharged from a headbox into the nip of a twin forming wire prior to its passage over a curvilinear path defined by a forming roll. The water-surfactant solution is caused repeatedly to pass through the outer one of the twin forming wires until there is created, and stored in a silo, a foamed liquid containing about 65% air in the form of bubbles of from about 20 to about 200 microns in diameter. The foamed liquid is directed from the silo into a mix tank wherein a slurry containing fibers at 20% to 55% solids is added and mixed. The mixture is pumped to the headbox and into the nip of the forming wires. The outer wire retains the fibers while passing and again foaming the liquid for return to the silo and the mix tank for addition of fibers and return to the headbox.

Abstract: Alkylamine polyether surface active agent compositions and methods for using are described. The instant compositions are low foaming, and pH sensitive and are generally of the structure: ##STR1## in which (a) R.sub.1 may be hydrogen or alkyl;if R.sub.1 is hydrogen then R.sub.2, R.sub.3 and R.sub.4 must be alkyl having a total number of carbon atoms falling in the range of 7 to 23;if R.sub.1 is alkyl, then R.sub.2, R.sub.3 and R.sub.4 may be alkyl or hydrogen, the total number of carbon atoms in R.sub.1 +R.sub.2 +R.sub.3 +R.sub.4 falling in the range of 7 to 36 (preferably about 10 to 20);(b) The --(C.sub.2 H.sub.4 O).sub.m -- segment must be a poly(oxyethylene) homogeneous chain or "block" polymer (i.e., a homopolymer), m having an average value in the range of 1 to 15, preferably 5 to 13; and(c) Y is selected from the group consisting of:(1) homogeneous poly(oxypropylene) chain (PO) "block" polymer or residue (i.e., a homopolymer), of the structure --(C.sub.3 H.sub.6 O).sub.

Abstract: A method of killing and inhibiting the growth of microorganisms in industrial process streams comprises the addition of an enzymatically catalyzed biocide system utilizing a microbial or plant dehydrogenase enzyme such as peroxidase or laccase in the presence of an oxidant such as hydrogen peroxide or oxygen to oxidize phenolic compounds found in or added to the process streams to produce oxidation products that are toxic to microorganisms.

Abstract: Apparatus for supplying deaerated stock to a processing machine incorporates an enclosed receiver and an open receiver open to the atmosphere. Stock deaerated by vacuum in the enclosed receiver flows to the processing machine, preferably via the open receiver. Some of such stock spills over a weir associated with the open receiver to maintain a constant-level pond in such receiver. Such constant-level pond minimizes stock pressure fluctuations at the machine. The apparatus may be provided with devices for controlling the level of stock in the conduit leading from the enclosed receiver and for passing stock from the enclosed receiver to the conduit in a predictable flow pattern to minimize generation of pulsations at the entry to the conduit. The stock spilling over the weir in the open receiver is recycled. During a temporary shutdown of the processing machine, the system may be maintained in operation with continuous recirculation of stock through the receivers to facilitate rapid restarting of the machine.

Abstract: In the production of multi-ply paper in a twin-wire former of the kind in which the wires define a curved forming zone, preferably a former of roll type with a smooth-faced forming roll, a substantially improved layer purity is produced in that the discharges from a first and at least succeeding portion of the curved forming zone are collected separately as different fractions. The first fraction collected nearest the multilayer headbox is returned in a first separate circuit to be used for diluting a first high consistency pulp to a first stock of headbox consistency, from which stock a first layer is to be formed directly on the outer wire in relation to the curved forming zone. At least a portion of a second fraction collected at a greater distance from the multilayer headbox is returned in a second separate circuit to be used for diluting a second high consistency pulp to a second stock of headbox consistency, from which a second layer is to be formed superimposed on the first layer.

Abstract: Apparatus for supplying deaerated stock to a processing machine incorporates an enclosed first receiver and a second receiver open to the atmosphere. Stock deaerated by vacuum in the first receiver flows to the second receiver. Some of such stock spills over a weir associated with the second receiver to maintain a constant-level pond in such receiver. Stock is supplied to the machine from such constant-level pond, so that the pond minimizes stock pressure fluctuations at the machine. The stock spilling over the weir is recycled to the first receiver. During a temporary shutdown of the processing machine, the system may be maintained in operation with continuous recirculation of stock through the receivers to facilitate rapid restarting of the machine. Because there is no need for a pond of stock in the enclosed receiver, such receiver may be compact. The system may be installed in a preexisting mill and space within a preexisting vessel may be used for the second receiver.

Abstract: Apparatus and method for the manufacture of a non-woven fibrous web, such as paper, from a dispersion of fibers in a foamed liquid. In a preferred embodiment, a solution of surfactant in water is initially discharged from a headbox into the nip of a twin forming wire prior to its passage over a curvilinear path defined by a forming roll. The water-surfactant solution is caused repeatedly to pass through the outer one of the twin forming wires until there is created, and stored in a silo, a foamed liquid containing about 65% air in the form of bubbles of from about 20 to about 200 microns in diameter. The foamed liquid is directed from the silo into a mix tank wherein a slurry containing fibers at 20% to 55% solids is added and mixed. The mixture is pumped to the headbox and into the nip of the forming wires. The outer wire retains the fibers while passing and again foaming the liquid for return to the silo and the mix tank for addition of fibers and return to the headbox.

Abstract: A carboxylated latex is added to an aqueous slurry of fibers to remove metal ions contained in solution. The water is removed to form a felt. The demetallized water removed during felt formation is recycled in a closed process water system. The carboxylated latex is formed by polymerizing an unsaturated carboxylic acid on a substantially surfactant free styrene-diene polymer latex.

Abstract: A method of killing and inhibiting the growth of microorganisms in industrial process streams comprises the addition of an enzymatically catalyzed biocide system utilizing a microbial or plant dehydrogenase enzyme such as peroxidase or laccase in the presence of an oxidant such as hydrogen peroxide or oxygen to oxidize halide salts, or phenolic compounds found in or added to the process streams to produce oxidation products that are toxic to microorganisms.

Abstract: Unbleached sulphae fibres are chemically separated from other fibres by the use of high molecular polyalkylene oxides, preferably polyethylene oxide. The polyalkylene oxides are added to aqueous suspensions of fibre mixtures and hereby flocculates unbleached sulphate fibres in a selective manner and the flocks can be separated by known methods such as sedimentation, flotation, filtration etc. Use of polyalkylene oxides for selective flocculation of unbleached sulphate fibres gives the possibility of upgrading for example recovered fibres, broke and secondary fibre raw materials.

Abstract: In order to obtain a more uniform sheet-like glass fiber product, it has been discovered that the use of a treating formulation having phosphate esters of polyoxyalkylene alkyl alcohol, polyamine compound, organic acid with glass fibers gives a more uniform aqueous dispersion of glass fibers. The treating formulation can be added to the aqueous solution to which the glass fibers are to be dispersed and then the more uniform aqueous dispersion of glass fibers is conveyed to a separator to produce the more uniform sheet-like glass fiber product from the aqueous dispersion and the aqueous dispersion is recyled to disperse fresh glass fibers. Also, the treating formulation can be present by itself on glass fibers that are in a wet condition. In addition, the treating formulation can be present on glass fibers that are in a dry condition when the treating formulation is applied to the glass fibers from a sizing composition containing the treating formulation and a film-former.

Abstract: A method for producing fire retardant or non-combustible fibrous products. Fibrous organic or inorganic materials, or a mixture thereof, are processed into a slurry, which is then intimately mixed with a boron-containing mineral and a mineral acid. The mixture is allowed to ripen, and is fed into a sheet forming and dewatering apparatus to form a dewatered, fibrous web, which is dried to form the fibrous product.

Abstract: The potassium compounds in heavy black liquor flowing in the recovery cycle are reduced by the introduction of magnesium nesosilicate to form magnesium potassium silicate which is voided from the system by filtration.

Abstract: Starch fibrids useful in enhancing the physical properties of non-woven webs, e.g., paper, are produced by a process which comprises providing an aqueous, alkaline solution of a water-insoluble starch in a finely divided form, e.g., in the form of an aerosol, and introducing the finely divided starch solution into an agitated, aqueous precipitating medium comprising a precipitating salt to thereby produce starch fibrids characterized by having both film and fiber morphology. The starch fibrids are recovered from the salt-containing liquid and may be incorporated into paper to improve the physical properties thereof.

Abstract: Method of producing fiberboard products according to the so-called dry method from lignocellulosic fiber material in which the fiber material discharged from a defibrating apparatus in an environment of steam is propelled in a stream of heated air to remove substantially all moisture therefrom. The thus dried fibers are deposited on an underlying moving perforated screen to form a mat in which the fibers are oriented at random while propellant air is evacuated therefrom. The thus formed mat is wetted by adding water thereto while it is being advanced by the screen into a hot press where the wetted fibers are compressed and bonded in their random orientation, with consequent removal of water. The amount of water added in the wetting step is proportioned to be effective in itself to bond the fibers without use of extraneous bonding or adhesive substance.

Abstract: A method for controlling the microorganism in aqueous systems comprising treating such systems with a biocidal amount of a mixture of 75% of 5-chloro-2-methyl-4-isothiazolin-3-one and 25% 2-methyl-4-isothiazolin-3-one with chlorine or chlorine dioxide.

Abstract: The present invention relates to certain compositions and processes useful for inhibiting the growth of microorganisms in water and, in particular, water used for industrial purposes; for example, in the manufacture of paper, in cooling water systems, in effluent water treatment, and in secondary recovery petroleum operations. The novel processes and compositions of the present invention are processes or mixtures which show unexpected synergistic activity against microorganisms, including bacteria, sulfate-reducing bacteria, fungi, and algae, which produce slime in aqueous systems where such slime is objectionable from either an operational or aesthetic point of view. Specifically, the invention is directed to the use of compositions comprising 2-(thiocyanomethylthio)benzothiazole and 2,2-dibromo-3-nitrilopropionamide.

Abstract: A method and apparatus for forming a fibrous web between a pair of forming wires. The apparatus includes an imperforate rotatable roll and a pair of liquid permeable forming wires which meet about a portion of the surface of the rotatable roll. Means are provided for delivering a liquid suspension of fibers between the forming wires as the wires are being received about a portion of the rotatable roll. The specific improvement of the present invention is centered around an arcuate imperforate roof conforming to the periphery of the rotatable roll along a limited part of the portion in which the twin wires are forming the sheet, with injection means for injecting pressurized air along the surface of the roof to form an air film therealong. Collector means are provided at the end of the forming portion for collecting liquid expelled from the forming wires during their travel along the portion of the roll.

Abstract: Waste water effluent from online production machinery and/or clean-off water from shut-down machinery is deposited in a settling tank in which the solids settle out. Water, relatively clear of the solids, is returned to the production plant. A slurry containing a high concentration of these solids is, depending on the percentage of solids, either returned to the production machinery via a slurry tank or returned to the settling tank for further concentration. The degree of concentration of solids in the slurry tank is carefully controlled in order to permit the addition of these otherwise wasted solids to the virgin asbestos-cement slurry in the various production machineries. This addition of the otherwise wasted solids is carefully monitored at each of the production machinery installations in order to provide proper quality control of the product produced thereby.

Abstract: A method of treating papermaking white water which contains dissolved solids, usually of a biodegradable organic nature. According to the invention, the dissolved organic solids, which are objectionable because they cause process equipment corosion, undesirable product and process odors and water pollution, are treated with ultraviolet light so as to lower their concentration and eliminate these problems. The light treatment causes material of relatively simple chemical structure to polymerize into more complex, less soluble materials which can easily be removed from the system as they become less soluble. The method is applicable to papermaking and other industries process using large quantities of process water. The treatment cell, which preferably operates on clarified white water, may be placed in series with the process white water flow or in parallel therewith, and can be operated as a continuing treatment process or as a intermittent treatment process.

Abstract: A method of making fiberboard using a substantially closed white water system. One or more layers of separately prepared surface pulp is applied to a layer of base pulp at the wet sheet forming stage. Lignocellulose chips in a pressure-sealed defibrating zone under generation of steam. The steam is separated at the discharge end of the defibrating zone under atmospheric pressure. The atmospheric steam is utilized to presteam the raw chips. The presteamed chips are thereafter dewatered to a moisture content coordinated to the energy demand of the defibrating treatment and the desired generation of steam prior to entering the defibrating zone. The water removed at the dewatering stage is collected for use in preparing the surface layer pulp suspension. A small portion of the base pulp to be used for the surface layer pulp is diverted to a refiner and diluted with water.

Abstract: The water resulting from the filter press molding of slurries of hydrated lime and reactive silica in the manufacture of hydrous calcium silicate products is recycled to the process by treating it with carbon dioxide to precipitate dissolved calcium hydroxide, filtering, and returning the filtered water to the process step wherein the lime and silica are slurried in water.

Abstract: An improved process for forming a non-woven fabric by wet-laying, on paper making equipment, staple length, synthetic fibers having a length to diameter ratio of about 400 to 3000, and an improved, non-woven fabric produced by the process. The process involves forming a stable, viscous, uniform, air-fiber-water dispersion by: adding the fibers to a high-shear agitated mixture of water and a dispersant to separate the fibers and to completely and uniformly distribute the individual fibers throughout the resulting, high-shear agitated, air, water and fiber mixture; and then, slowly adding a thixotropic thickener to the high-shear agitated mixture to form the viscous, air-fiber-water dispersion, having a nascent viscosity of about 10 to 125 cps., when measured at a shear rate of 30.5 sec..sup.-1, and in which the individual fibers are restrained from becoming entangled and from forming knits, bundles, and strings.

Abstract: Water-soluble polyamines which (a) have an average molecular weight of above 1,000, (b) contain at least one grouping of the formula-- R -- Zin whichZ denotes a --COOH or --SO.sub.

Abstract: A fibrous web is continuously formed between inner and outer endless foraminous forming belts between which stock slurry is fed from a headbox, the belts being held in tension as they wrap a first convexly curved forming run surface from which the outer belt is separated immediately following the forming run, the inner belt carrying the wet web then running over a second convexly curved surface from the offrunning side of which the inner belt is then separated and a porous pickoff belt is pressed by a substantial convex area of an imperforate pickup roll against the wet web on the inner belt, the inner belt being guided to diverge from the pickoff belt commencing at the off-running end of the convex area of contact of the pickup roll and the wet web being forced to adhere to the pickoff belt by the vacuum action of the imperforate surface of the pickup roll. By multiplication of the apparatus a multiply web can be formed.

Abstract: The waste water obtained from a papermaking process is purified to remove the last traces of fibers suspended in the water by mixing the waste water with those contaminating materials that are separated from the paper pulp suspension before it is fed to the papermaking machine. These contaminants act as a filter aid and make it possible to separate the fibers remaining in the water phase after the water from the papermaking machine has been subjected to a flocculating process, filtering and screening.

Abstract: A continuous wet-laid process for making high-strength glass fiber mats is described. In the process, glass fibers of known quantity are fed directly into a water stream of given volume to form a flowing fiber slurry of predetermined fiber consistency. Immediately thereafter, the flow of the slurry is interrupted turbulently to form a uniform fiber dispersion. The dispersion then is conveyed quickly onto a moving mat-forming wire screen to form the desired mat. The water thus-removed is recirculated into the original stream to provide a continuous operation. The process may be used advantageously for making high-strength mats of relatively long glass fibers, which find utility in the manufacture of asphalt roofing shingles, and as backing sheets for vinyl flooring.

Abstract: A method of removing liquid from a slurry of solid material in liquid in which the liquid is squeezed from the slurry by passing the slurry through a roll nip and, simultaneously with the squeezing and passing, the liquid squeezed from the slurry is blocked from flowing through the roll nip.Apparatus for removing liquid from a slurry of solid material in a liquid includes a plurality of liquid guides, disposed in a spaced-apart parallel relationship, being inclined away from and opening adjacent the roll nip.

Abstract: Disclosed is a method for coagulating the suspended solids in paper mill waste water so that the coagulated solids may be easily separated from the waste water and the clarified waste water reused in the paper making process. Coagulation is induced by first adding sulfuric acid to lower the pH to below 4, mixing thoroughly, and then adding calcium hydroxide to raise the pH to above 10. The coagulated solids separated from the waste water may be used as a landfill, used as a low grade pulp source, or dewatered and burned as a fuel.

Abstract: A continuous, essentially closed recirculating papermaking process is provided by using a dispersing medium of adjustable viscosity. The process permits the continuous reuse of the medium under preferred operating conditions. It includes the steps of forming a dispersion of fibers within the adjustable medium containing a pH sensitive viscosity producing agent, reducing the fiber consistency and the viscosity within the dispersion while maintaining the concentration of the agent substantially unchanged, subsequently forming a fibrous web material on a papermaking screen from said dispersion of reduced fiber consistency while separating the dispersing media from the fibers forming the web and continuously collecting the separated media and recirculating it within the system to effect a subsequent fiber dispersion as well as a fiber consistency reduction and viscosity reduction without substantially changing the concentration of the viscosity producing agent.

Abstract: Wet-lay papermaking processes employing urea-formaldehyde resin in a papermaking slurry for imparting wet strength to the paper, are improved by addition of a water soluble salt of carboxymethylcellulose to the papermaking slurry, preferably when the urea-formaldehyde resin is dispersed in the slurry. The carboxymethylcellulose salt substantially increases the wet strength cure rate of the paper without significantly affecting the ultimate wet strength properties imparted to the paper by the cured urea-formaldehyde resin.

Abstract: Slime in industrial process waters can be dispersed and prevented by treating the waters with a few ppm of the enzyme, Rhozyme HP-150, a pentosanase-hexosanase.

Abstract: An improved process for forming a non-woven fabric by wet-laying, on paper making equipment, staple length, synthetic fibers having a length to diameter ratio of about 400 to 3000, and an improved, non-woven fabric produced by the process. The process involves forming a stable, viscous, uniform, air-fiber-water dispersion by: adding the fibers to a high-shear agitated mixture of water and a dispersant to separate the fibers and to completely and uniformly distribute the individual fibers throughout the resulting, high-shear agitated, air, water and fiber mixture; and then, slowly adding a thixotropic thickener to the high-shear agitated mixture to form the viscous, air-fiber-water dispersion, having a nascent viscosity of about 10 to 125 cps., when measured at a shear rate of 30.5 sec..sup.-1, and in which the individual fibers are restrained from becoming entangled and from forming knits, bundles, and strings.

Abstract: A slurry of cellulosic material is diluted to a flowable consistency and subjected to a pressure differential on a permeable surface to increase the slurry consistency to a value between the consistency of the diluted slurry and the consistency of the slurry prior to dilution thereby forming a mat of cellulosic material on the permeable surface. The liquid and solids which pass through the permeable surface as a result of the pressure differential are recycled for use as slurry diluent, and to the mat of cellulosic material, while the mat remains on the permeable surface and subject to the pressure differential, is countercurrently applied, in a plurality of treatment stages, a treating liquid, such as a wash liquid, including application of a fresh treating liquid to said mat in the last stage of said treatment stages, whereby the treating liquid displaces at least a portion of liquid present in said mat from said mat and through the permeable surface in each treatment stage.

Abstract: The discharge pipes of a plurality of stock pumps, each supplying a separate concentrated stock slurry, are connected with a pipe containing comparatively dilute stock, commonly called "white water", discharged under pressure from a single fan pump on a single white water silo to supply separate slurries to separate chambers of a multi-ply web forming machine. The stock pumps have smaller capacities and pressure heads compared with a fan pump, thereby providing increased efficiency at required capacity with the minimum of equipment.

Abstract: A slurry of cellulosic material is diluted to a flowable consistency and subjected to a pressure differential on a permeable surface to increase the slurry consistency to a value between the consistency of the diluted slurry and the consistency of th slurry prior to dilution thereby forming a mat of cellulosic material on the permeable surface. The liquid and solids which pass through the permeable surface as a result of the pressure differential are recycled for use as slurry diluent, and to the mat of cellulosic material is applied a treating liquid, such as a washing liquid.

Abstract: Lignocellulose fiber containing chips, preheated with steam liberated from a previous chip defibration, are dewatered and then defibrated in an atmosphere of saturated steam and in the presence of backwater and suspended in backwater to form a pulp suspension whereafter wet sheets are formed from the pulp suspension, water is mechanically removed from the wet sheets and recycled as backwater to be supplied simultaneously, with dewatered chips, to the defibration step and to form a new pulp suspension and said wet sheets are dried.

Abstract: Hardboard is produced by a process wherein wood solubles or sugars released principally during the pulp preparation stage are retained in a closed water system by collecting the process waters released during mechanical dewatering of the pulp to form a mat and returning such water to the system. The mat is dried by thermal evaporation with substantial quantities of sugars being deposited on the mat surfaces as a result. The mat is then pressed under conditions such as to cause flowing and caramelization of the surface sugars thus forming a crust or skin of the sugars on the mat surfaces, which sugars improve the board surface characteristics. A paper overlay may be applied to the mat prior to pressing and bonded thereto by the sugars to provide a paper overlaid hardboard.

Abstract: A method of producing textile-like non-woven essentially binderless webs from fiber furnishes at least about 70% of which comprise man made non-fibrillatable low denier fibers having no large area flat surfaces and which are at least about 1/4 inch in length with a length to diameter ratio of between about 400:1 and 700:1. The method includes a wet laying system in which sufficient wetting agent is added to the water used in dispersing the fibers to wet the fibers completely and reduce the surface tension of the water to between about 30-35 dynes. It also includes agitating the dispersion vigorously to create tumbling water surface conditions in which up to, but less than about 4% by volumeof air is entrained in the water in the form of tiny air bubbles to create a water/air emulsion in which the fibers are dispersed without generating any substantial amount of surface foam.

Abstract: An improved method for the manufacture of wood fiberboard according to the wet system with a closed white water system includes the steps of drying the incoming lignocellulose containing material, prior to the dilution step, to a dryness, or solid consistency, which is higher than the dryness of the wet lap or sheet before final drying to produce the fiberboard product. Formaldehyde is added to the resulting white water which is homogenized to atomize occurring precipitations through efficient agitation and dispersion prior to being recirculated for use for diluting the incoming fiber material. Thus, there is obtained an efficient closed white water system which results in a reduction of environmentally harmful discharge of polluted water as well as the production of fiberboard with enhanced appearance.

Abstract: An improved method for the manufacture of wood fiberboard according to the wet system with a closed white water system includes the steps of drying the incoming lignocellulose containing material, prior to the dilution step, to a dryness, or solid consistency, which is higher than the dryness of the wet lap or sheet before final drying to produce the fiberboard product. Formaldehyde is added to the resulting white water which is homogenized to atomize occurring precipitations through efficient agitation and dispersion prior to being recirculated for use for diluting the incoming fiber material. Thus, there is obtained an efficient closed white water system which results in a reduction of environmentally harmful discharge of polluted water as well as the production of fiberboard with enhanced appearance.

Abstract: A method of treating papermaking white water which contains dissolved solids, usually of a biodegradable organic nature. According to the invention, the dissolved organic solids, which are objectionable because they cause process equipment corosion, undesirable product and process odors and water pollution, are treated with ultraviolet light so as to lower their concentration and eliminate these problems. The light treatment causes material of relatively simple chemical structure to polymerize into more complex, less soluble materials which can easily be removed from the system as they become less soluble. The method is applicable to papermaking and other industries process using large quantities of process water. The treatment cell, which preferably operates on clarified white water, may be placed in series with the process while water flow or in parallel therewith, and can be operated as a continuing treatment process or as a intermittent treatment process.