Abstract: A paper former comprises two wires which converge for defining a paper production gap and a plurality of dewatering blades arranged in the paper production gap in a paper producing direction and brought into sliding contact with one of the two wires so that a stock is dehydrated while being conveyed in a state put in the paper production gap. Each of the plurality of dewatering blades is shaped into a convexly curved surface configuration bent along a traveling direction of the wires and equipped with a wire sliding contact surface brought into sliding contact with said wire for guiding the traveling of said wire, and grooves are made in said wire sliding contact surfaces as a moisture run-off opening for running off moisture developing through the dewatering from the wire side. This paper former thus constructed can suppress the occurrence of paper defects stemming from the landing of a material jet or paper defects stemming from the dewatering property, thus improving the paper quality.

Abstract: Device for the washing and dewatering a fibrous suspension, which device incorporates two hollow, circular cylindrical filter drums (1), which filter drums incorporate evacuation chambers inside the filter drums for evacuation of fluid. The filter drums rotate in opposite directions to create a pinch (2) where at least one of the said filter drums (1) is installed in a trough (7,8) which partly encloses the outer surface (3) of the filter drum and which, in the direction of rotation of the filter drum, converges towards the outer surface of the filter drum. At least one pulp inflow chamber (4) is installed at the highest point (1) of one or both of the filter drums each equipped with a trough for the introduction of pulp between the outer surfaces (3) of the filter drum and its trough (7,8) for the formation of a fibrous web.

Abstract: A twin wire former in a machine for the production of a fibrous material web, specifically a paper or cardboard web, includes two rotating continuous wires which meet in the area of a simultaneously rotating dewatering element, thereby forming a stock inlet gap; and a headbox over which the fiber stock suspension is fed into the stock inlet gap. The stock consistency C of the fiber stock suspension in the headbox, as well as the basis weight F of the fiber stock suspension supplied to the stock inlet gap is selected according to the calculation: F/(C*1000)>0.025 whereby the basis weight F is stated in g/m2 and the stock consistency C is stated in g/l.

Abstract: A web of tissue is formed in a twin wire former, followed by an air press for water removal in the pressing section, passing onto a Yankee dryer. A headbox injects stock between upper and lower dryer fabrics brought together on a breast roll. The fabrics move over vacuum boxes, and the web is heated with steam and passed between an upper pressure box and a lower vacuum box forming an air press which dewaters the web. A sheet transfer pickup vacuum box holds the sheet to the upper fabric as the lower fabric diverges from the upper fabric. A pressure roller transfers the web onto a Yankee dryer. The fabrics are cleaned on vertical runs before returning to the breast roll.

Abstract: A non-woven web of cellulosic synthetic fibrous material is produced using a twin wire former. The former may have a closed first end and closed first and second sides, and a second end provided by first and second moving foraminous elements. An interior structure between the sides and second end may have at least first and second different length pluralities of conduits extending from the former first end toward the second end, and defining by themselves, or with wall elements, the interior volume into a first volume and a second volume on opposite sides thereof. A first fiber/foam slurry is introduced into the first volume and a second fiber/foam slurry in the second volume, and suction box assemblies are provided on the opposite sides of the foraminous elements from the interior volume for withdrawing foam from the slurries to forming a non-woven web on the foraminous elements.

Abstract: Plies that are formed by respective formers are couched together in a sheet forming device, specifically a machine for the production of a multi-ply fiber web, particularly a paper or cardboard web, or a packaging paper web. At least one of the formers for forming a multi-ply web includes a multi-layer headbox, to which at least two different stocks, or stock partial streams of different composition for different plies are furnished.

Abstract: The invention concerns an equipment and a method in a twin-wire former, in which a partly pre-drained or non-drained fiber stock is passed to between the forming wires of the web former in the vicinity of the former roll (11) or of a water drain box, in which connection water is drained out of the stock web by means of the former roll (11) or the water drain box. The twin-wire former comprises a rib (20) in connection with the former roll (11) or the water drain box in the lateral area of the wires (H2), which rib has been fitted to control the running of the second forming wire H2) passed from the gap roll. By means of the rib (20), in the lateral area of the wire runs, the point at which said forming wire (H2) reaches contact with the first forming wire in connection with the former roll (11) or the water drain box is shifted further away in the machine direction. The rib (20) is an oblong structure, which has a maximal height (Hmax) in the middle area of the rib (20).

Abstract: A method and apparatus for improving forming of a web of paper or paper board employing prepressing during web forming. Forming wires are brought together over at least one roll or alternatively two rolls. The web then passes, sandwiched between two wires through one or more pressure nips which may be one or more roll nips or an extended nips. The pressure nip may be formed as the web travels between the two fabrics, one of them being a forming wire, along a straight path or alternatively as the web travels partially around a roll. The web is then sandwiched between a wire and a fabric, which may be a felt or a belt, and passed through another press nip which may be one or more roll nips or an extended nip.

Abstract: A compact multilevel paper making machine is provided comprising a web-receiving region where a web of paper is received on a fabric forming a continuous loop, a reel-up for winding the paper web onto a roll, and a web transfer point disposed between the web-receiving region and the reel-up. The fabric receives the web at the web-receiving region and then supports and transports the web from the web-receiving region to the web transfer point in a first direction on a first defined vertical level. At the web transfer point, the web is separated from the fabric. The fabric loop further includes a return run from the web transfer point to the web-receiving region over which the fabric then travels. A cleaning section is also disposed along the return run of the fabric loop for cleaning the fabric.

Abstract: The invention concerns an integrated paper machine, which comprises, in the running direction of the web, a multi-layer headbox (100), a gap former (200), in which there is at least one pre-press (303, 304), a press section (300), in whcih there is at least one extended-nip press (308, 309), a pre-dryer section (400), in which the web (W) is dried by means of a high-capacity dryer unit, a dryer section (500), in which there is at least one dryer group (R1, R2, R3) which makes use of single-wire draw, as well as a surface treatment device (P) for the web. Further, the paper machine is provided with a closed web draw at least to the end of the dryer section (500).

Abstract: A twin wire former in a machine for the production of a fibrous material web, specifically a paper or cardboard web, includes two rotating continuous wires which meet in the area of a simultaneously rotating dewatering element, thereby forming a stock inlet gap; and a headbox over which the fiber stock suspension is fed into the stock inlet gap.

Abstract: A through-air drying paper making apparatus is provided comprising a twin-fabric forming section, a water-removing section arranged downstream of the forming section, and a web transfer device disposed between the forming section and the water-removing section. The forming section includes a forming roll, a pair of fabrics guided to travel about a portion of the circumference of the forming roll, and a headbox operable to deposit a slurry between the fabrics so as to form a paper web therebetween. Preferably, one of the fabrics in the forming section comprises a through-air drying (TAD) fabric arranged to carry the paper web through the water-removing section, while the other fabric comprises a forming wire. At the web transfer device, the paper web is separated from the forming wire and the paper web then carried on the TAD fabric through the water-removing section. The water-removing section includes at least one through-air dryer for at least partially drying the paper web.

Abstract: A papermaking machine and a method for applying an application medium to a moving web of material in a papermaking machine. The papermaking machine has a wet end section, a press section, a drying section and an applying device for applying a medium to a moving web of material. The wet end section includes a twin wire area having a first wire and a second wire wherein the web of material is formed and positioned between the two wires and separated from the two wires before moving to the press section. At least one wet end section applying device is positioned on one side of at least one of the first wire or the second wire within the twin wire area and facing away from the web of material positioned on the wires. The press section of the papermaking machine has a first press element and at least one press section applying device facing directly toward the web of material.

Abstract: A method and apparatus for beginning the formation of a paper web on a traveling forming wire, or between a pair of converging forming wires, includes a headbox on a papermaking machine for projecting a stock stream onto the forming wire, or between the forming wires over the porous face surface of a forming shoe. The forming wire or wires are looped to travel in a continuous path, and within at least one of the looped forming wires is the forming shoe, which is porous by way of grooves or openings over at least a portion of its face surface. The grooves are in the surface of the forming shoe which engages the inner surface of the looped forming wire to define a portion of the path of travel of the forming wire adjacent the headbox from which the stock stream is projected onto, or between, the forming wire(s). The grooves extend in the surface facing the forming wire from a point downstream of the leading edge in the nose portion of the face surface of forming shoe in the direction of forming wire travel.

Abstract: An arrangement for adjusting the width of a fibre web in an apparatus comprising two filter wires permeable to water, the filter wires having the same direction of travel, and a conduit for placing pulp suspension between the wires. The arrangement comprises channel for feeding water between the wires and to the edges thereof.

Abstract: A flexible mounting for use in the forming section of a twin forming fabric paper making machine consisting essentially of a base member supported by the paper making machine structure to which is attached a flexible C-shaped beam. The C-shaped beam has one edge attached to the base member, and a fabric contacting blade attachment means at the other edge. A pressurized loading tube is located within the C-shaped beam between the base member and the second edge of the C-shaped beam. When the pressurized loading tube is loaded, the C-shaped beam flexes thus allowing the blade to move initially into contact with a forming fabric. As the pressurized tube is further loaded, the contact face of the blade is moved into further engagement with the forming fabric. In a preferred construction, the wrap angle of the fabrics at or about the blade leading edge can be minimized. The mounting thus can diminish wear of the fabric as it passes over the blade.

Abstract: Wire section, guidance device, and process of forming a web in a machine for producing a fibrous material web. The device include two revolving endless wire belts, a twin wire zone formed between the two revolving endless wire belts, and a revolving flexible support belt located in a vicinity of the twin wire zone and positioned to support at least one of the two wire belts in a support region. The flexible support belt is generally guided along an at least essentially circular cylindrical path, and the support region includes a support path having an average curvature radius that is greater than a curvature radius of the essentially circular path. The process includes supporting at least one of the two endless wire belts with the flexible support belt in a support region, rotating the flexible support belt along a generally circular path, and deflecting the support belt from the generally circular path in the support region, whereby the support belt in the support regions travels along a support path.

Abstract: A sheet forming system of a paper or cardboard machine. A headbox includes a headbox nozzle with to laterally extending side panels and first and second nozzle walls extending along a width of the machine. First and second screens converge in a region adjacent the headbox nozzle. At least two guide mechanisms, each having a guide surface, guide the first and second screens in the region. At least one support mechanism supports at least a portion of one of the first and second nozzle walls against said guide surface of at least one of said at least two guide mechanisms.

Abstract: A dewatering instrument for a paper machine twin-wire former for improving the fiber dispersion performance while avoiding the decrease in strength of formed paper in its thickness directions. In the dewatering instrument, dewatering inhibiting blades have plane sections for supporting a wire and inclined surfaces for defining wedge-shaped spaces spreading out toward the upstream side in the wire traveling direction with respect to a wire plane formed on a wire entry side of the plane sections. Angles (wedge-angles) between the inclined surfaces and the wire are set to become sequentially smaller as a whole in proportion as the dewatering inhibiting blades are positioned on the further downstream side in the flowing direction of a paper raw material liquid.

Abstract: A pressurized box is positioned opposite a vacuum box. The pressurized box has a leading cross machine direction baffle with a ceramic shoe which engages a forming fabric, and a trailing cross machine direction baffle of similar construction. Two end deckles complete the pressurized box. The leading cross machine direction baffle presses against a resilient seal which causes a web contained between upper and lower forming fabrics to wrap about the baffle shoe a few degrees forming an effective end seal which does not allow air to bypass the baffle. The trailing cross machine direction baffle is positioned over a vacuum box which prevents air from leaking around the trailing baffle. A vacuum box draws air through the forming fabrics and the web, from the pressurized box increasing the total pressure gradient across the web to 20 to 30 psi or more. The pressure box and opposed vacuum box form an air press. The pressure box is positioned and held against the forming fabrics by opposing air tubes.

Abstract: Device for the washing and dewatering a fibrous suspension, which device incorporates two hollow, circular cylindrical filter drums (1), which filter drums incorporate evacuation chambers inside the-filter drums for evacuation of fluid. The filter drums rotate in opposite directions to create a pinch (2) where at least one of the said filter drums (1) is installed in a trough (7,8) which partly encloses the outer surface (3) of the filter drum and which, in the direction of rotation of the filter drum, converges towards the outer surface of the filter drum. At least one pulp inflow chamber (4) is installed at the highest point (1) of one or both of the filter drums each equipped with a trough for the introduction of pulp between the outer surfaces (3) of the filter drum and its trough (7,8) for the formation of a fibrous web.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering.

Abstract: A method and apparatus for beginning the formation of a paper web on a traveling forming wire, or between a pair of converging forming wires, includes a headbox on a papermaking machine for projecting a stock stream onto the forming wire, or between the forming wires over the porous face surface of a forming shoe. The forming wire or wires are looped to travel in a continuous path, and within at least one of the looped forming wires is the forming shoe, which is porous by way of grooves or openings over at least a portion of its face surface. The grooves are in the surface of the forming shoe which engages the inner surface of the looped forming wire to define a portion of the path of travel of the forming wire adjacent the headbox from which the stock stream is projected onto, or between, the forming wire(s). The grooves extend in the surface facing the forming wire from a point downstream of the leading edge in the nose portion of the face surface of forming shoe in the direction of forming wire travel.

Abstract: The invention relates to a method of recovering energy in a forming section of a papermaking or boardmaking machine, wherein stock from a headbox is fed into a forming zone of a forming section, said forming zone including at least one looped forming fabric curving along a convex surface of a support member, and water is drained from the stock through said at least one forming fabric in the forming zone to form a paper or board web, the water passing through said at least one fabric being thrown out from the forming zone and possessing kinetic energy, characterized by placing a movable component in the water thrown out from the forming zone, so as to cause the water to move the component, and thereby recovering part of the kinetic energy. The invention also relates to an arrangement in a papermaking or boardmaking machine.

Abstract: A stock feed system for a multi-layer headbox and a method in the operation of a multi-layer headbox in which into each inlet header of the multi-layer headbox, a stock concept is passed which has been produced out of the same fresh stock by adding the necessary chemicals and fillers to separated portions of the fresh stock.

Abstract: A process arrangement for the short circulation in a paper or board machine including stock chests for component stocks, metering pumps for component stocks, cleaning devices, pumps, a headbox and a wire section as well as a system of pipes connecting these elements, together with regulation devices. After the metering pumps, the component stock flows are passed into a closed mixing volume in which the component stocks are mixed and diluted with a first dilution water flow. From this closed mixing volume, the stock is passed in a closed space by a first feed pump of the main line of the process through a screen and a centrifugal cleaner to the suction side of a second feed pump of the main line, where a second dilution water flow is passed to the stock. The second feed pump feeds the stock through a machine screen to the inlet header in the headbox.

Abstract: Twin wire former and method for manufacturing a fibrous material web from a fibrous suspension using same. The twin wire former comprises a movable bottom wire belt and a movable top wire belt converging at a twin wire zone. The twin wire zone has a first section, a second section and an end section. A rotating forming roller is disposed at the first section of the twin wire zone, and the to wire and the bottom wire form a wedge-shaped inlet gap at the first section of the twin wire zone. The inlet gap is adapted to receive the fibrous suspension from a headbox. The bottom wire belt and the top wire belt are adapted to form the fibrous web therebetween at the second section of the twin wire zone, and the second section of the twin wire zone has at least one drainage element. A separating device is disposed at the end of the twin wire zone and is adapted to separate one wire belt from another the wire belt.

Abstract: A twin-wire former adapted to form a web of fibrous material is provided. First and second endless circulating wire bands define a twin-wire zone therebetween, and form the web of fibrous material therebetween. The first and second wire bands run over a forming roll in the twin-wire zone, where the first wire band contacts the forming roll. A reel-off point is defined as the point at which the first and second wire bands disengage from the forming roll. At least one support device extends crosswise over the second wire band. The support device is a hinged foil skimmer, and is disposed in a region of the reel-off point, and contacts the second wire band. Movement of the second wire band relative to the at least one supporting device creates an area of reduced air pressure therebetween. The method includes moving the first and second wire bands adjacent a forming roll such that the first wire band contacts the forming roll. The first and second wire bands disengage from the forming roll at a reel-off point.

Abstract: A wet section (10) of a paper or cardboard machine and a process for the manufacture of a fibrous material web are suggested. The wet section (10) exhibits a double-screen segment (US), in which two screens (16, 18) are guided about parallel to one another and into which a fibrous material suspension (27) is introduced. The double-screen segment (US) is looped around a roll (22). The means (30, 32, 38) for the immobilization of the fibrous material suspension in the double-screen segment (US) are provided on the roll (22), for the formation of the fibrous material web. Moreover, the wet section exhibits means (32, 34, 36; 34, 36, 66) for further draining of the fibrous material web.

Abstract: Twin-wire former for producing a fibrous material web from a fibrous suspension and process for separating upper and lower wires of the twin-wire former. The twin-wire former includes a twin-wire zone composed of a lower wire and an upper wire and a plurality of rolls including an inlet roll and an outlet roll. The upper wire is guidable over the plurality of rolls, the inlet roll guides the upper wire to the twin-wire zone, and the outlet roll guides the upper wire toward the inlet roll. A wedge-shaped inlet zone is formed between the upper wire and the lower wire and has an adjustable inlet wedge angle. An upper wire subassembly includes a drainage box adapted to receive suspension water that flows upwardly through the upper wire, and further includes a pivotable common support device, to which the drainage box and the inlet roll are mounted. A stroke device is coupled to the pivotable common support device to lift the pivotable common support device around a first horizontal axle.

Abstract: The invention refers to a process for dewatering a pulp web, particularly a chemical pulp web, where dewatering takes place between twin wire belts or felts in an initial dewatering zone with a set area pressure and then in a second dewatering zone. It is mainly characterized by the area pressure in the initial dewatering zone being pre-set, and in the second dewatering zone it is adjustable, with the web being dewatered in both directions (upwards and downwards). The invention also refers to a device for implementing the process.

Abstract: Apparatus and method for forming a continuous web on a forming fabric includes providing a pressurized chamber, processing the forming fabric through the pressurized chamber, and distributing a pressurized flow of a slurry having a first composition in the pressurized chamber across the width of the forming fabric to form the continuous web.

Abstract: In order to render a twin wire former for a paper machine more applicable to an appropriate dewatering pressure state with respect to widely used paper formation conditions, there is provided a dewatering device including a plurality of dewatering blades that face a gap for paper formation through the wires constituting closed loops. The dewatering blades comprise a pressure adjustment unit for operating the dewatering blades in a direction close to or away from a wire and an angle adjustment unit for swinging the dewatering blades in a wire running direction, which are operationally associated with each other. The angle formed between an active plane of the dewatering blades and the wires is externally adjustable by the angle adjustment unit.

Abstract: Ash from a recovery boiler is purified by leaching or evaporation-crystallizing contaminants such as, chlorides and potassium salts in water. The leaching or evaporation-crystallizing takes place in an aqueous solution at a temperature that is in the vicinity of the boiling point of the aqueous solution. The leached or evaporation-crystallized ash is returned to the black liquor or to the recovery boiler while the leaching water or the evaporation-crystallization water is then cooled to less than 32.degree. C., preferably 10-15.degree. C. Sodium sulphate containing crystallization water, such as sodium sulphate heptahyfdrate or sodium sulphate decahydrate, is crystallized out and then separated to be reintroduced into the black liquor, directly into the recovery boiler or into the leaching solution or evaporation-crystallization solution.

Abstract: A method for impregnation and chemical digestion of lignocellulosic material and recovery of pulping liquors. A spent impregnating or cooking liquor is withdrawn and sulphurous compounds are recovered therefrom in a partial oxidation reactor. These sulphurous compounds are converted into hot liquid elemental sulphur which thereafter is mixed with a hot sulphide containing liquor to provide a polysulphide liquor with a concentration greater than 10 g/l and which is essentially free from thiosulphate. This polysulphide liquor is used for carbohydrate stabilising impregnation and/or for cooking at a relatively low temperature.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering. The air press has an air plenum and a vacuum collection device, each on opposite sides of two support fabrics that sandwich the paper web. There are cross machine sealing blade(s) that impinge upon the support fabrics and is opposed on the other side of the support fabrics by a sealing member formed of deformable material. The air plenum and vacuum collection device are movable relative to one another so that the sealing blade and deformable sealing member form a seal in the operating position of the air press.

Abstract: A method for the manufacture of non-chlorine bleached pulp, from alkaline digested cellulose pulp, wherein a suspension of the cellulose pulp is subjected to a series to oxygen gas delignification (O), treatment with complexers (Q) and bleaching with non chlorine-containing oxidative bleaching agents (O,P,Z). The various treatment stages interspersed with washing and/or reconcentration of the cellulose pulp in at least one stage, in conjunction with which a suspension liquid is conveyed essentially in strict counter-current, with the result that the pulp manufacturing process is essentially totally closed with regard to the liquid circuit.

Abstract: A process for conditioning an ozone gas recycle stream in an ozone pulp bleaching process, wherein the level of carbon dioxide in the recycle stream is controlled to allow full capacity operation of the ozone generator. Carbon dioxide concentration is identified over the relevant operational ranges and maximum concentration is identified for full capacity/optimum efficiency operation. Specific methods are described for controlling carbon dioxide concentration including purging a portion of the recycle stream, counter-current scrubbing of the recycle stream with an alkaline solution and passing the recycle stream through an adsorbent material. Contaminants entering the system also may be reduced by directing the purged recycle stream, which is relatively oxygen rich, into the dewatering press where pulp consistency is increased. In this manner nitrogen surrounding the pulp is displaced by oxygen and thus, does not enter the bleaching/ozone system with the pulp.

Abstract: Process for recovering chemicals and energy from black liquor, where the black liquor is gasified with CO, CO.sub.2, CH.sub.4, H.sub.2, and H.sub.2 S, in gaseous form, and Na.sub.2 CO.sub.3, NaOH and Na.sub.2 S, in the form of drops of smelt, being principally formed. The mixture of gas and smelt is cooled, in a first stage, by direct contact with a cooling liquid, whereupon a part of the cooling liquid is volatilized, and the smelt drops are separated off and dissolved in the remaining part of the cooling liquid with the formation of a liquid bath of green liquor. In a second stage, the gas is washed and saturated with moisture by direct contact with a washing liquid bath. After the gas has been washed in the second stage, energy in the form of thermal energy and condensation heat is recovered from the gas in an indirect condenser.

Abstract: An air press for noncompressively dewatering a wet web to consistency levels not previously thought possible at industrially useful speeds without thermal dewatering.

Abstract: A method of separating impurities from lime or the calcium carbonate or the lime sludge produced in the chemical recovery system of a pulp mill so that lime sludge or lime is dissolved in a solution containing carbonate or hydrocarbonate in order to dissolve impurities. Subsequently the lime sludge or lime is separated from the solution containing dissolved impurities. A method of causticizing green liquor containing impurities, such as silicon, in two stages. In the first stage green liquor is causticized with such an amount of lime that impurities substantially remain in the liquor. The lime produced in this stage is removed from the liquor and the rest of the lime required in the causticizing is added to this liquor, so that impurities precipitate with the lime sludge produced in the second stage and at least a portion of the lime sludge rich in impurities is discharged from the process.

Abstract: A method of treating solid-containing material contained in or produced from an effluent or waste from a process for the treating of waste paper. The solid-containing material includes constituents of the waste paper and organic material including cellulose fibers and inorganic particulate material including calcium carbonate and other inorganic particulate material included in the waste paper. The solid-containing material is subjected to a heat treatment that incinerates the organic material present and forms from the inorganic particulate material present a calcined product including calcium oxide from thermal decomposition of calcium carbonate. The calcined product is formed into an aqueous suspension wherein calcium oxide is converted to calcium hydroxide.

Abstract: Provided is a quench vessel containing at least two separate internal vessels. A receiving liquor is contained in the first internal vessel and a washing liquid bath is contained in a second internal vessel.

Abstract: When closing the process of manufacturing cellulose pulp of high brightness, i.e. including the recovery of essentially all waste liquor, there is an untenable enrichment of certain basic elements, such as sodium and sulphur. The present invention provides a partial solution to this problem and is concerned with a method in bleaching with ozone lignocellulosic material, e.g. cellulose pulp, which has been at least partially manufactured chemically, in the presence of water at a degre of acidity, expressed as pH, of 2-5. The method is characterized in that the acidity is maintained during the ozone bleaching process by adding a sulphuric acid solution or an acid sodium sulphate solution produced by electrolysis or electrodialysis of an essentially neutral sodium sulphate solution obtained by recycling chemicals in a system to which waste liquor from the ozone bleaching process is added.

Abstract: The invention relates to an apparatus in a paper or board machine for dewatering the web prior to its passage to a press section. The dewatering is effected by a pair of rolls, which is located at the end of a wire section upstream of a pick-up suction roll or a similar transfer device. An additional wire is brought in contact with a side of the web opposite that of the wire of the wire section and it is passed together with the wire of the wire section and the web through the pair of rolls. One of the rolls is an open-surfaced roll for receiving water from the web over its area of contact with the path of travel formed by the wires and the web. The other roll of the pair of rolls is a smooth-surfaced roll and is in contact within the area of contact with the path of travel formed by the wires and the web on the opposite side.

Abstract: Provided is a process for recovering chemicals and energy from spent liquor obtained when producing paper pulp by chemical delignificatation of fibrous raw material. The spent liquor is gasified in at least two reactors, a first and a second stream of solid and/or smelt material and of combustible gaseous material being formed. The formed material is treated in one or more devices (5, 6, 7, 8), whereby a first (9) and a second liquor (27) are formed. The pressure and/or temperature in the first reactor differ(s) from the pressure and/or temperature in the second reactor. In addition, one or more process chemicals are recovered selectively from the formed liquor and/or gas, and are thereafter returned in whole or in part to one or more of the reactors (1, 2) and/or to one or more of the devices (5, 6, 7, 8) for treatment of the formed material.

Abstract: A Pulp Mill Recovery installation for producing liquors containing different concentrations of recovered process chemicals or combustion gasses containing different concentrations of process chemicals from a spent liquor obtained from the production of pulp.

Abstract: The invention concerns the wire section of a papermaking machine and a method of removing water from a fiber web in that section. A fiber suspension is discharged from a headbox on at least one and usually between two wires in the forming section. The fiber suspension is dewatered until it eventually reaches the point of immobility at which the fiber orientation is fixed. The rate of removal of water transverse to the direction of travel of the web is controlled at regions across the web. In particular, the rate of water removal is decreased at the edge regions of the wire and the web, as compared with the center region, to improve the transverse formation profile of the web.

Abstract: Provided is a process for removing metals from a bleaching plant spent liquor and recovering a chelating agent which includes the steps of: heating a spent liquor containing a chelate comprising metals bound in a chelating agent to a temperature of at least about 140.degree. C.

Abstract: The invention relates to a process for producing polysulphide by means of oxidizing sulphide in spent liquors from kraft cellulose cooking. The process is characterized in that green liquor is firstly enriched in sulphide and then oxidized.