Abstract: Described is a machine for manufacturing a continuous web, in particular a paper or cardboard web, the machine having a number of rolls that may include press rolls, drying cylinders, suction rolls, or the like. At least one transport belt is guided with the web around the rolls and is characterized by the fact that a metallic screen is guided between the web and the respective roll surface. The metallic screen may be formed of metal, formed as a metallized drying screen, or formed from metal and synthetic threads.

Abstract: A calender hood for a paper machine having a dryer section and a calender section the hood extending along a portion of the paper path from the dryer section through the calender section to restrict movement of the ambient air into the region between the surface of the paper sheet and the calender hood and thereby reduce heat losses to the ambient air by the paper sheet.

Abstract: A press-to-dryer apparatus is disclosed for pressing and drying a web of paper. The apparatus includes a press for pressing the web of paper and a dryer disposed downstream relative to the press for drying the web. The dryer includes an unfelted drying cylinder disposed immediately downstream relative to the press. The arrangement is such that the web extends from the press to and around the drying cylinder. The dryer also includes a heater which cooperates with the unfelted drying cylinder such that the web is disposed between the drying cylinder and the heater for heating and drying the web. The dryer also includes a single-tier drying section which is disposed downstream relative to the unfelted drying cylinder for completing the drying of the web.

Abstract: A heatable roller which can be heated from inside the roller body by a heating device. Provided radially outside the heating device are axially parallel bore holes uniformly distributed over the periphery of the roller body which are connected at the ends by annular chambers. The bore holes and the annular chambers form a closed system which is partially filled with water. This system operates to make the temperature uniform via condensation heating in the event of local temperature reduction.

Abstract: A method for reducing the consumption of fresh water and energy in a paper mill in which fresh water is passed into the paper mill for various needs, and a cooling tower is utilized for cooling water heated in the papermaking process. All fresh waters or a substantial proportion of the fresh waters of the paper mill are introduced into the process through the water system of the cooling tower. The cooling tower includes at least one inlet for passing the water to be cooled into the cooling tower, nozzles for discharging the water that was passed in and that is to be cooled onto heat transfer faces, filler pieces and/or filler plates, which disperse the water to be cooled so as to increase the contact area between the water and the cooling air, at least one outlet for passing the cooled water out of the cooling tower, and blowers for blowing the cooling air through the cooling tower.

Abstract: A paper machine roll, in particular for a soft calender or supercalender, which includes a metal frame, roll ends, and shafts. The frame is coated with a polymer coating over at least a middle area or central region thereof while lateral regions may optionally remain uncoated. In order to equalize a difference in temperature between the roll ends and the optionally non-coated lateral regions of the metal frame, on one hand, and the coated central region area of the roll, on the other hand, an arrangement for equalizing the difference in temperature is provided by heating the roll ends and the optionally non-coated lateral regions of the metal frame.

Abstract: A paper making machine for the production of a fiber material web includes a drying cylinder, first and second bearing assemblies, a fixed rigid support, a fixed structure and a flexible device. The drying cylinder has two longitudinal ends, a longitudinal axis and at least one fluid passage for receiving heated fluid. Each bearing assembly is attached to and rotatably carries a respective longitudinal end of the drying cylinder. The fixed rigid support substantially immovably supports the second bearing assembly. The flexible device allows for longitudinal thermal expansion of the drying cylinder in a direction substantially parallel to the longitudinal axis of the drying cylinder. The flexible device carries the first bearing assembly and interconnects the first bearing assembly to the fixed structure.

Abstract: The invention is directed to an apparatus to produce layers of material, such as paper, carton or cardboard, under use of at least one roll that can be heated in a controlled manner, in particular a dryer cylinder, with tubing attached to the end of the roll that supplies the energy necessary to heat up the roll. Bearings at both ends of the roll are mounted to a seating structure. One of the bearings is a freely carrying bearing and the steam supply is rigidly attached to the seating structure.

Abstract: An integrated flue gas treatment and condensing heat exchanger is used to scrub sulfur dioxide from the flue gas produced by a power boiler used in a paper mill operating a kraft process. Sensible and latent heat from the flue gas is recovered and the condensate effluent from the condensing heat exchanger contains valuable chemicals that are returned to and used in the kraft process.

Abstract: A steam applicator to apply steam to a web passing by the applicator. The applicator is a main supply header and a plurality of profiling steam chambers to receive steam from the main supply header. The pre-heat chambers adjacent the profiling steam chambers. The flow of steam is controlled from the main supply header to each profiling steam chamber. At least one outlet in each profiling steam chamber allows a supply of steam from the applicator. The supply of steam from each outlet can be controlled. The apparatus is compact and has the virtue avoiding condensate dripper onto the web.

Abstract: A method of regulating the temperature in a chemical melt dissolving tank, where chemical melt produced in combustion of spent liquor of a cellulose pulp mill is dissolved in liquid, producing green liquor, provides excellent heat economy, while minimizing the amount of liquid needed to dissolve the melt to produce green liquor at a temperature below boiling. Green liquor produced in the dissolving tank is expanded (and thereby cooled) in a vacuum tank, and a least a significant part of the cooled liquor is returned to the dissolving tank, for regulating the temperature in the tank. The heat energy contained in the generated expansion steam may be used in many different ways, for example, for indirectly heating (e.g. in a heat exchanger acting as a condenser) water or other liquid to a sufficiently high temperature so that the liquid is useful elsewhere in the pulp mill.

Abstract: An apparatus for use in the pulp industry for recovering heat in the spent liquor recovery boiler, whereby the boiler walls are formed of water-cooled tubes connected to the water/steam circulation system of the boiler. Supply of air into the lower section of the furnace is effected symmetrically through air ports which are disposed at equal distances from the center of the furnace. The lower section of the furnace is preferably cylindrical and connected to a separate cooling medium circulation system.

Abstract: The invention overcomes the problem of paper edge overdrying during the paper drying process on paper machine drying cylinders. It comprises applying a thin ceramic coating onto the circumferential exterior surface of the cylinder near the cylinder edges, thereby forming a thermal barrier coating which decreases paper drying rate at said edges and reduces or eliminates paper edge overdrying.

Abstract: An apparatus and method for treating a sheet material (3) with an arrangement of rollers (6, 7), including at least one heated roller (8, 9), which defines at least one roller gap through which the sheet of material is passed and acted upon with pressure and/or elevated temperature. A housing (32) surrounds the roller arrangement (6, 7) and the treatment takes place in an environmental atmosphere, the temperature and/or humidity of which can be adjusted to a specified value. A roll of the sheet material is subjected to pretreatment to provide it with desired temperature and humidity conditions before entering the housing (32).

Abstract: A method and apparatus for use in the pulp industry for recovering heat in the spent liquor recovery boiler, whereby the boiler walls are formed of water-cooled tubes connected to the water/steam circulation system of the boiler. The lower section of the boiler is defined by water tubes connected to a separate water circulation system of a forced type. Thus, heat is preferably recovered in the lower section of the boiler by a separate water circulation system having a lower pressure than in the water/steam circulation system of the boiler.

Abstract: The invention relates to a method and apparatus for use in the pulp industry for improving the safety of a spent liquor recovery boiler, such as a soda recovery boiler. The boiler comprises, for recovering chemical and energy, a furnace cooled by water tubes and connected to the water/steam circulation system of the boiler, the cooling of the bottom of the furnace being provided by a separate cooling circulation. The separately cooled lower section of the furnace is provided by separating the bottom or the bottom and part of the furnace walls from the boiler water circulation system. This separated section is supplied with a cooling fluid of its own which may be a gas (e.g. air or inert gas) or a liquid (e.g. molten zinc) which does not cause an explosion of it contacts the melt of the furnace.

Abstract: A chip feeding system for a continuous digester provides for a greater rate of delivery of chip slurry to the digester, and is much less expensive than conventional chip feeding systems, typically being only 40-50% of the height of the conventional system. An atmospheric vessel may be connected at the bottom thereof to a slurry pump which pumps the chip slurry to a conventional high pressure feeder. A recirculation loop for returning liquid from the feeder to the vessel may include an atmospheric level tank, and a liquid cooler. The vessel may have one dimensional convergence and side relief, and instead of a conventional cylindrical chip bin, the chip bin may have a hopper having two transitions with one dimensional convergence and side relief. The chip bin also may be at atmospheric pressure so that no low pressure feeder between the bin and vessel is necessary.

Abstract: A method and device for intensifying the operation of a Yankee press in a soft-tissue machine in which a web is pressed in one or several nips formed between a Yankee cylinder and one or more press rolls. The web is dried on the Yankee cylinder by blowing hot air introduced through the Yankee hood against the web. In the method, a blow device is used to blow hot and humid air against the web. The blow air for the blow device is taken from the outlet/heat recovery of the air system of the Yankee hood, and the exhaust air from the blow device is returned to the outlet/heat recovery of the air system of the Yankee hood. Air is blown against the web at the proximity of the nip formed between the Yankee cylinder and the first press roll, before and near the first press nip, in the running direction of the web. The blow device includes a blow chamber, an exhaust chamber, and blow nozzles for blowing hot and humid air against the web and exhaust-air ducts for the removal of the air.

Abstract: Apparatus for cooling the end portions of a calender roll which has an elastic layer adjacent its peripheral surface and wherein the central portion of the peripheral surface is overlapped by a running web of paper or other material when the calender is in use. The width of the non-overlapped portions of the peripheral surface of the roll varies when a web having a first width is followed by a web having a different second width. This could lead to damage to the roll at the non-overlapped portions of the peripheral surface as a result of overheating by an adjacent rotary component of the calender. The end portions of the roll are cooled by discrete adjustable cooling devices which are movable along the respective non-overlapped portions of the peripheral surface in parallelism with the axis of the roll and each of which shares movements with a monitoring device which is to be maintained in a selected position relative to the adjacent marginal portion of a running web.

Abstract: Disclosed is a polishing doctor blade for resurfacing the surface of a metal calendering roll while in operation, comprising a working surface containing diamond abrasive particles harder than the surface material.

Abstract: Method and system for applying steam to a paper forming web for the purpose of heating the web to improve the quality of the paper, and withdrawing steam through the use of a vacuum opposite the steam shower, by the simultaneously controlled removal of steam at equally spaced increments by the use of a computer based control system. The computer based control system includes a selectively actuable stepper motor, to effectuate the simultaneous opening of both the steam valve and opposing withdrawal means valve. The system includes a coanda nozzle to cause steam to travel between the sheet and the adjacent surface of the apparatus in a direction opposite to the direction of travel of the sheet and also includes steam impingement nozzles. The apparatus includes devices for creating, housing and providing a supply of steam and a supply of vacuum.

Abstract: A press apparatus and method for pressing water from a paper web is disclosed. The apparatus includes a frame and a first press roll which is rotatably supported by the frame. A second press roll cooperates with the first roll for defining therebetween a pressing nip such that in use of the apparatus, the web extends through the nip for pressing the water therefrom. An elastomeric cover covers at least one of the rolls such that the pressing nip is extended in a machine direction so that the residence time of the web during passage of the web through the nip is increased.

Abstract: An apparatus and method is disclosed for removing fluid from a fibrous web. The apparatus includes a press member and a blanket which cooperates with the press member for defining therebetween an elongate pressing section such that the web is pressed between the press member and the blanket during passage through the pressing section. An elongate shoe urges the blanket towards the press member such that when the web passes through the pressing section, fluid is removed from the web. A heater is disposed adjacent to the press member for transferring heat to the web such that when the web passes through the press section, the web is subjected for an extended period to increased pressure and temperature so that water vapor generated within the pressing section during passage through the pressing section forces the fluid in the liquid phase away from the web. The press member defines a pressing surface which is porous so that delamination of the web is inhibited.

Abstract: Multi-cylinder dryer, has upper cylinder (13,14,15,16) and lower cylinders (10,11,12) over which a paper web (W) to be dried is run in meandering fashion from one cylinder onto the next cylinder. The paper web is in direct contact with each drying cylinder within a sector that is larger than 180.degree.. An upper wire (5) and a lower wire (6) are used to press the paper web against faces of the drying cylinders (10,11,12; 13,14,15,16). The wires (6,5) are guided by guide rolls, which are placed in such a way that the paper web (W) is continuously supported by a wire (5,6) as it runs from one cylinder onto the other. The guide roll arrangements consist of fragmentary rolls (21,51), which are supported on suction boxes (20) and/or on blow boxes (50) so that at least two fragmentary rolls (21,51) are supported on each suction box (20)/blow box (50). By means of the suction boxes (20)/blow boxes (50), blowings (S,P) are directed at the drying wire (5,6).

Abstract: Method for pressing and dewatering a paper web, in which a hot-pressing stage is utilized where the wet paper web is pressed in direct contact with a cylinder face that has been heated to a temperature higher than about 100.degree. C. A relatively long pressing time and a relatively low compression pressure are applied in a pre-heating/pre-pressing stage. In this preliminary stage, a surface layer of the cylinder that heats the paper web is heated to a temperature higher than about 100.degree. C. In the immediately following stage, the compression pressure applied to the paper web is lowered so that vaporization of the water present in the paper web is intensified.

Abstract: A method and system for cooling pulp discharged from a batch type digester and recovering heat from it. A stream of pulp together with spent cooking liquor is discharged from a batch digester to a diffuser and passed through the diffuser at substantially the same pressure as that of the digester. The pulp stream is caused to flow between screens and hot spent cooking liquor is displaced with cooler liquor flowing across the pulp stream thereby lowering the temperature of the pulp stream. The displayed cooking liquor and the pulp is withdrawn from the diffuser.

Abstract: The present invention is an air guide box. The box has a guide wall intended to lay adjacent to a running web. The guide wall has an air suction channel and a discharge opening. A drive jet blows air into the air suction channel to create suction, with the air being expelled through the discharge opening.

Abstract: An apparatus and method is disclosed for removing fluid from a fibrous web. The apparatus includes a press member and a blanket which cooperates with the press member for defining therebetween an elongate pressing section such that the web is pressed between the press member and the blanket during passage through the pressing section. An elongate shoe urges the blanket towards the press member such that when the web passes through the pressing section, fluid is removed from the web. A heater is disposed adjacent to the press member for transferring heat to the web such that when the web passes through the press section, the web is subjected for an extended period to increased pressure and temperature so that water vapor generated within the pressing section during passage through the pressing section forces the fluid in the liquid phase away from the web. The press member defines a pressing surface which is porous so that delamination of the web is inhibited.

Abstract: A floater dryer for drying a web-shaped (W), moving material, in particular a paper or cardboard web. The dryer comprises a plurality of radiation/air blowing units (10) which are provided on one side of the web (W) or on both sides (10A,10B). The units (10) have been shaped to be blow boxes having on their side facing the web (W) a contact-free carrier surface (21R,27) and into conjunction with which is blown, through a nozzle aperture (20a,20b) opening on the leading and/or trailing edge of the carrier surface, an air jet (Ful), or air jets (Fua,Fub). The jets will have a substantially large component parallel to said carrier surface. In conjunction with the radiation/air blowing units (10) are provided radiation elements (30) from which into the treatment interval (P.sub.1, P.sub.2, P-) is directed radiation (S.sub.O) through a window (27). The window at the same time serves as carrier surface for the air support of the web (W). The air flows (F.sub.3,F.sub.

Abstract: A headbox for dispensing a machine-width suspension flow from a machine-width nozzle type discharge channel which is defined by two machine-width flow control walls converging on each other. Located on the downstream end is a machine-width discharge gap for the flow of suspension. One of the two flow control walls is for fine adjustment of the discharge gap width and is equipped with an elastically flexible wall section which extends across the machine width. This wall section is equipped with a number of areal heating elements in a succession across the machine width, with which material layers having different coefficients of heat expansion may be coordinated. By appropriate heating of individual heating elements it is possible to achieve a local deformation of the flexible wall section and thus a local change of the discharge gap width and a correction of the basis weight cross profile of the paper web produced.

Abstract: Method and apparatus for drying paper webs continuously manufactured in paper machines, by the use of process steam produced by a two-substance compression heat pump with a solution-circuit.A portion of the thermal energy needed for the drying process is obtained from process steam produced by the heat pump from the waste heat contained in the moist exhaust air of the paper machine, and another portion from preheated ambient air, which is then used for drying the paper web. The ambient air is preheated by using it to cool the rich solution of the heat pump.

Abstract: A press apparatus is disclosed for removing fluid from a fibrous web. The apparatus includes a press member and a blanket cooperating with the press member for defining therebetween an elongate pressing section such that the web is pressed between the press member and the blanket during passage through the pressing section. The blanket is urged towards the press member such that when the web passes through the pressing section, fluid is pressed from the web. A heating device is disposed adjacent to the press roll for transferring heat to the web such that when the web passes through the pressing section, the web is subjected for an extended period to increased pressure and temperature so that water vapor generated within the pressing section during the passage of the web through the pressing section forces the fluid in the liquid phase away from the web.

Abstract: A dryer for paper and similar fibrous web materials including a dryer roll having an outer cylindrically-shaped wall, a radiant heat source within the dryer roll adapted to heat the wall substantially uniformly about the entire periphery thereof, and nip-forming means forming a pressure nip with the dryer roll.

Abstract: A method for the moistening of an endless web moving in a processing device, wherein the moistening substance is an evaporated fluid condensated on the web and said web is treated with a corresponding steam substance prior to this moistening. The method includes steps for supplying the evaporated fluid in a bag-like member formed by the web, the bag-like member being supported by an external member. The supply of the substance is carried out by means of a steamer appliance arranged transverse to the web. The method includes steps for adjusting the specific property of the steam substance in accordance to specific values measured from the web.

Abstract: In order to control the moisture profile of paper webs in the cross machine direction thereof in the dryer part of the paper making process a built-up insulating sheet fixedly wound around a part of the circumferential surface of a drying cylinder is composed of a fluorine resin coated sheet having an adhesive agent coated layer on the reverse side thereof and an air-containing synthetic fabric adhered to said fluorine resin coated sheet and having a width slightly smaller than that of said fluorine resin coated sheet. The built-up insulating sheet is adhered to the circumferential surface of the drying cylinder at the appointed positions thereof through the adhesive agent coated layer exposed at the end portion of the fluorine resin coated sheet.

Abstract: A drying cylinder for use in the drying part of a paper making process. The moisture profile of paper web is equalized all over the width of said paper web by fixedly winding synthetic fabric around the surface of a drying cylinder contacting with wet paper web at the appointed positions thereof to form the void areas among yarns of said synthetic fabric as highly insulating air-holding portions.

Abstract: The invention concerns a process and device for molding and drying objects made of fibrous materials.The device comprises a cylinder 12, rotating about its longitudinal axis, having a row of porous molds 18 along the lengths of said cylinder's lateral faces, partially dipping into a vat 10 maintained with a constant level of fibrous product paste made of an appropriate liquid, a tubule 20 which connects the interior of the cylinder with a source of vacuum so as to create a partial vacuum therein, said cylinder 12 surrounded on its entire lateral surface free between paste vat 10 and removal device 22 by an arrangement of insulating walls 42 which define with cylinder 12 and vat 10 an enclosure 44 into which opens passageway 46 conveying hot air, said hot air being dwarfed from the extraction of air from a dryer.The present invention notably applies to the formation of egg boxes.

Abstract: Methods and apparatus for drying a web of material running between a drying cylinder and a traveling covering cloth avoid the formation of air boundary layers which would impede heat exchange with respect to, and humidity removal from, the traveling web. In particular, these methods and apparatus avoid excessive wear of the covering cloth by locating a baffleplate at a distance from the covering cloth within a domain of the boundary layer, and promote a heat exchange and humidity removal through turbulence by impacting air from the boundary layer against a front surface of the baffleplate at a distance from the covering cloth, causing an exchange of air in the boundary layer and in meshes of the covering cloth. Effects of non-uniform humidity profiles are avoided by providing the front surface of the baffleplate with a varying configuration across the covering cloth.

Abstract: A moist, porous web is consolidated and dried by running it through the nip between two rotatable rolls, the surface of one of which is heated as it approaches the nip. One side of the web is in direct contact with the surface of the heated roll and the other side faces a permeable surface. The rolls are pressed together under high pressure to transfer heat from the heated roll to the web compressed therebetween to dry the same. The roll surface may be heated by hot gases from a fuel combustion burner or by a liquid medium. The dried and consolidated web may be removed from the heated roll by doctoring or it may be conveyed from the nip between the rolls to apparatus for processing it further.

Abstract: Apparatus to supply steam to a paper sheet passing beneath it. The apparatus has a leading edge and a trailing edge relative to the sheet direction and comprises at least two headers, a first header being adjacent to the leading edge. There is a steam supply system means for the headers. A profiling chamber is formed between the headers and baffles which divides the profiling chamber into compartments. There is provision for a controlled supply of steam to each compartment. Outlets in the profiling chamber permit steam to be projected towards the sheet from the compartments. A further chamber is formed adjacent to the leading edge and steam can be supplied to the chamber. Outlets in the further chamber permit steam to be directed towards the sheet to form a steam curtain at the leading edge of the apparatus to prevent air being drawn under the apparatus by the sheet.

Abstract: An apparatus for the drying of a slurry being conveyed on a movable support including a steam producing arrangement below the movable support forming a steam atmosphere. A film of condensed vapor is produced above the slurry caused by heat transfer through the movable support, and an air drying arrangement is adapted to propel a stream of air across the slurry surface so as to entrain the vapor therein and to remove it from the slurry.

Abstract: A Fourdrinier steam shower positioned over the wire includes a steam distributor pipe extending across the path of motion of the machine wire and fed with pressurized steam. This steam pipe is connected to support members in the Fourdrinier machine. Positioned around said steam pipe for the width of the machine wire is a steam distributor including legs extending downward and outward from the pipe at an angle so as to define and enclose a steam chamber open at the bottom. Steam enters the steam distributor from jets in the steam pipe and is directed through a tortuous path into the steam chamber. Water collecting in the legs of the steam distributor is discharged through drains located at the bottom of each leg.