Abstract: A web forming apparatus includes a drum portion and a second web forming unit. The drum portion has an accommodating chamber capable of accommodating fragments, and accommodating powder supplied from a first supplying unit. The second web forming unit forms a second web by letting a mixture containing the fragments and the powder falling from the drum portion accumulate. The first supplying unit includes a storing chamber for storing the powder and an outlet portion provided below the storing chamber. The powder goes out of the storing chamber via the outlet portion. The drum portion has meshes formed in a net demarcating the accommodating chamber. The powder is able to pass through the meshes. The outlet portion is provided vertically over the net of the drum portion.

Abstract: A system comprising: (a) a steam box; and (b) a monitoring system that monitors cleanliness of the steam box and is configured to connect to a paper machine.

Abstract: Described herein are different distributed sensor network models, use cases, and details of the components of each model to achieve the goal of monitoring, detecting, tracking, and mitigating a target(s) such as a signal, an object, a phenomenon, etc. An independent sensor or a local sensor network may supply data to one or more fusion center(s) that collect(s) data and perform(s) higher logic to enhance system performance. A local sensor network allows independent sensors or other local sensor networks to merge into the local sensor network. A sensor cloud can be formed by multiple local sensor networks and independent sensors. By using different distribution models, the local sensor network can provide protection for various targets like Very Important Personnel (VIP) vehicles, lands, facilities, and cities.

Abstract: A dynamic, reconfigurable, and modular cleaning device utilizes software, sensors, and modular components to provide a one-size-fits-all approach to cleaning conveyor belts. The cleaning device secures to a body or frame associated with a conveyor belt, in which an associated cleaning head cleans the conveyor belt's surface. The cleaning head has an arm that extends from its body and inserts into a corresponding opening on a connecting frame associated with the cleaning device. The cleaning head is then secured in place via a cylindrical pin that extends through aligned holes on the arm and the connecting plate. Insertion of the pin connects the components together, and removal of the pin enables a user to disconnect the cleaning head and swap a new one in its place, such as to provide a different cleaning action.

Abstract: A system comprising: (a) housing; (b) support arm; and (c) rotary actuator that rotates a steam box between a working position and a rotated position.

Abstract: Methods and apparatus for vacuum forming a meat tray using a slurry. The slurry comprises: a moisture barrier comprising AKD in the range of about 4% by weight; a fiber base comprising bagasse; and an oil barrier comprising a water-based emulsion in the range of about 1.5% by weight.

Abstract: The vaporization type humidification unit includes a vaporization unit that evaporates moisture, a first blower that sucks humidification air humidified by the vaporization unit, a transport tube that is connected to the first blower and through which the air discharged from the first blower is transported, a second blower connected to the transport tube and discharging the humidification air discharged from the first blower side toward outside, an opening provided in a middle of the transport tube, a humidity measurement unit installed on a discharging side of the second blower, and a control unit that controls an air flow rate discharged from the first blower and the second blower, in which the control unit controls the air flow rate discharged from the second blower to a desired value and controls the air flow rate discharged from the first blower based on a humidity measured by the humidity measurement unit.

Abstract: A sheet fabrication apparatus includes: a fiber separation unit that micronizes an ingredient; a first sensor unit that measures a temperature in a first space including the fiber separation unit; a first air conditioning unit that adjusts the temperature in the first space; a fabrication unit that works the fiber separated articles obtained by micronizing the ingredient by the fiber separation unit; a second sensor unit that measures at least either a temperature or a humidity at a mounting position of the fabrication unit; and a control unit that controls the first air conditioning unit on the basis of at least any of measurement results of the first sensor unit and the second sensor unit.

Abstract: A sheet manufacturing apparatus includes a defibrator configured to produce defibrated material, a feedstock supply unit, a monitoring device, and a cleaning device. The feedstock supply unit includes a conveyance device configured to convey feedstock, a storage device configured to accumulate the feedstock conveyed from the conveyance device and supply the feedstock to the defibrator, and a measuring device configured to measure a state of the feedstock accumulated on the storage device. The monitoring device is configured to predict stopping of conveyance of the feedstock by the feedstock supply unit and activate the cleaning device when a conveyance speed of the feedstock by the feedstock supply unit becomes slower than during normal operation. The cleaning device is configured to execute on at least one of the conveyance device and the storage device a cleaning process that preemptively prevents the stopping of conveyance.

Abstract: An apparatus for cleaning a felt in a system for producing a paper web has a device for introducing a cleaning liquid into the felt and at least one following suction device in the direction of movement of the felt and having a vacuum duct, through which the cleaning liquid is suctioned out of the felt. The suction device between the vacuum duct and the felt is formed with suction ducts, through which the cleaning liquid in the felt is suctioned away. At least one of the suction ducts is assigned an inflatable valve element. In the inflated state of the valve element the suction duct is closed and in its ventilated state the suction duct is opened.

Abstract: A sheet manufacturing apparatus includes a defibrator configured to produce defibrated material, a feedstock supply unit, a monitoring device, and a cleaning device. The feedstock supply unit includes a conveyance device configured to convey feedstock, a storage device configured to accumulate the feedstock conveyed from the conveyance device and supply the feedstock to the defibrator, and a measuring device configured to measure a state of the feedstock accumulated on the storage device. The monitoring device is configured to predict stopping of conveyance of the feedstock by the feedstock supply unit and activate the cleaning device when a conveyance speed of the feedstock by the feedstock supply unit becomes slower than during normal operation. The cleaning device is configured to execute on at least one of the conveyance device and the storage device a cleaning process that preemptively prevents the stopping of conveyance.

Abstract: An apparatus and method to convert high resistivity (18 MOhm/cm) deionized water into lower resistivity deionized water with a tight resistivity range (150 KOhm/cm+\?50 KOhm/cm) without adding metals to the DI. The invention discreetly injects carbon dioxide in an on demand fashion through a metals free fluid path.

Abstract: A sheet manufacturing apparatus having: a defibrating unit configured to defibrate, in air, feedstock containing fiber; a mixing unit configured to mix, in air, resin with the fiber defibrated from the feedstock by the defibrating unit; an air-laying unit configured to lay a web from the mixture output from the mixing unit; a liquid application unit configured to add water to part of the web laid by the air-laying unit; and a sheet forming unit configured to form a sheet with parts having different light transmittance by heating and compressing the web to which water was added by the liquid application unit.

Abstract: A sheet manufacturing method includes defibrating a defibration object in the atmosphere, mixing, in the atmosphere, additive agents including resin into a defibrated material that has been defibrated, adjusting moisture of a mixture of the defibrated material and the additive agents, and heating the mixture that has been moisture-adjusted.

Abstract: A present sheet manufacturing apparatus, which manufactures a sheet including defibrated material and whiteness enhancer, is provided with a defibrating unit configured to defibrate a stock material that includes fibers, a whiteness enhancer feeding unit configured to feed the whiteness enhancer to the defibrated material defibrated in the defibrating unit. A feeding amount of the whiteness enhancer is changed based on whiteness information of the stock material or the defibrated material.

Abstract: A sheet manufacturing apparatus includes a defibrating unit configured to defibrate a defibration object including at least a fiber, in air. The sheet manufacturing apparatus forms a sheet by adding quantity of heat to a defibrated material defibrated at the defibrating unit. The sheet manufacturing apparatus includes a measuring unit configured to acquire moisture amount information of the defibrated material or the defibration object, and a controller configured to control the quantity of heat to be added to the defibrated material on the basis of the moisture amount information.

Abstract: A doctor blade cartridge for use in a doctor blade holder is disclosed. The doctor blade cartridge is for receiving a doctor blade, and includes at least one blade supporting member, wherein the blade supporting member is sufficiently stiff to support the doctor blade and includes load indication means for providing a signal indicative of at least one of blade supporting member strain and blade supporting member deflection.

Abstract: A machine for producing and/or processing a fiber web, in particular a tissue web, includes a press roll and a mating roll which forms a nip with the press roll and the circumferential surface of which has a contour running in the cross-machine direction which, during operation of the machine, changes as compared with when the machine is at a standstill. The press roll has a roll core and a roll cover surrounding the roll core. Multiple pressure and/or temperature sensors are disposed in the roll cover and/or between the roll core and the roll cover. The pressure and/or temperature sensors are spaced apart differently far from one another in the cross-machine direction of the press roll, at least in some areas.

Abstract: Embodiments of the present disclosure include methods to control the quantity of vapor phase corrosion, devices, and the like.

Abstract: This invention relates to a method and system for detecting contamination of boiler condensate and/or boiler feedwater in a papermaking process. The method includes measuring an oxidation-reduction potential at one or more locations in the boiler condensate and/or the boiler feedwater of the papermaking process with one or more corrosion stress monitoring devices. A controller is operable to assess whether the measured or a calculated oxidation-reduction potential is within an optimum range. The controller is operable to cause transmission of a signal to direct feeding an effective amount of one or more reductants and/or one or more pH-controlling chemicals into the boiler feedwater and/or one or more a satellite feed locations of the papermaking process.

Abstract: The present invention relates to a method for manufacturing a sheet-type substrate having a security thread, especially a banknote paper having a security thread, in which a) a security thread having features spaced apart from one another in the longitudinal direction of the security thread is inserted into the substrate in such a way that it is at least partially embedded in the substrate, b) at least one of the features is displayed as an image after the embedding of the security thread, c) the stretch of the embedded security thread in the longitudinal direction is calculated based on the image of the at least one feature, and d) the region of the substrate in which the calculated stretch of the security thread exceeds a specified maximum stretch is obliterated depending on the calculated stretch.

Abstract: A sheet manufacturing apparatus includes a defibrating unit configured to defibrate a defibration object, a measuring unit configured to acquire information relating to the moisture contained in the defibration object, and a controller configured to modify an operating condition of the defibrating unit based on the information.

Abstract: A sheet manufacturing apparatus includes a defibrating unit configured to defibrate a defibration object including at least a fiber, in air. The sheet manufacturing apparatus forms a sheet by adding quantity of heat to a defibrated material defibrated at the defibrating unit. The sheet manufacturing apparatus includes a measuring unit configured to acquire moisture amount information of the defibrated material or the defibration object, and a controller configured to control the quantity of heat to be added to the defibrated material on the basis of the moisture amount information.

Abstract: A present sheet manufacturing apparatus, which manufactures a sheet including defibrated material and whiteness enhancer, is provided with a defibrating unit configured to defibrate a stock material that includes fibers, a whiteness enhancer feeding unit configured to feed the whiteness enhancer to the defibrated material defibrated in the defibrating unit. A feeding amount of the whiteness enhancer is changed based on whiteness information of the stock material or the defibrated material.

Abstract: Apparatus for washing and dewatering pulp and a system for controlling this apparatus are provided. The apparatus includes a pair of rotatable press rolls installed in vats and including a press nip therebetween, an inlet for feeding the pulp to the press nip, with one of the press rolls being movable in relation to the other and in which the processing of the pulp is determined by the number of variable operating parameters. The system includes apparatus for utilizing the distance between the press rolls as a variable operating parameter, for setting a desired value for a specific control parameter, for measuring the specific control parameter, and for adjusting at least two of the variable operating parameters during operation to maintain the difference between the desired value and the measured value of the specific control parameter below a predetermined difference.

Abstract: A conservation control system is provided for integration with an cross-direction controller on a sheet making machine. The conservation control system receives inputs from the cross-direction controller and accepts and/or modifies the controller commands to a profiler based on desired performance and conservation trade-offs.

Abstract: A method includes receiving a measurement associated with an anisotropy of a first surface and a measurement associated with an anisotropy of a second surface of a sheet of material. The method also includes adjusting an operating parameter associated with a headbox based on the measurements. The headbox is associated with manufacture of the sheet. The operating parameter could include a jet speed, a jet impingement angle, a jet thickness, a slice opening, and/or a slice apron projection. Adjusting the operating parameter could be based on a difference between a measured anisotropy of the first surface and a measured anisotropy of the second surface. For example, the operating parameter could be adjusted to achieve a desired difference between the measured anisotropy of the first surface and the measured anisotropy of the second surface. Multiple headboxes could be controlled, such as when different headboxes are used to produce different layers of a multi-layer sheet.

Abstract: Partitioning control of the wet end and dry end, by introducing estimates of physical properties such as dry weight: and percent ash at the wire, allows for machine direction (MD) controls to continue during loss of scanner measurements. A mathematical model estimates the controlled, variables, such as dry weight, basis weight, and ash percent at the wire, and these estimated values are then controlled. When scanner measurements resume, parameters in the model are recursively updated to compensate for any model errors and ensure an accurate model. MD controls consist of a cascade set-up where the estimated wire-dry weight or wire basis weight and estimated wire ash percent are controlled by manipulating stock flow and addition of filler to stock. When scanner measurements are available, they become the downstream variables in the cascade control and are controlled by manipulation of the setpoints for the estimated wire weight and ash.

Abstract: A method and system for reducing waste water from a paper machine system. The system involves splitting a flow output from a seal water tank. With a portion of the flow output being used to maintain a fluid level within a wire pit, and the balance being recycled to the system as substantially clean water.

Abstract: The present invention provides a method of treating an aqueous system for biocide control, by adding an acidified solution that includes monoalkyldithiocarbamate salt and alkyl isothiocyanate to an aqueous system. A biocide feed system is also provided that is configured to generate a reproducible level of alkyl isothiocyanate. The method and system provide effective levels of alkyl isothiocyanate for rapid biocidal activity, along with levels of monoalkyldithiocarbamate salt which can decompose to form additional alkyl isothiocyanate and provide longer-term biocidal activity.

Abstract: The invention relates to a method for impregnating and drying a continuous paper web (1) by means of a urea resin dissolved in water, and to a corresponding system. Such paper webs (1) are employed for example as furniture foil or floor laminate, wherein in the known art melamine resin is used exclusively for bonding to a substrate. This is relatively expensive. Therefore the object of the invention is to create a method in which the paper web (1) which is impregnated by means of urea resin can be bonded to the substrate with a high degree of operational reliability. Said object is achieved in that the temperature of the paper web (1) is determined separately in each of the drying zones (3.1, 3.2, 3.3, 3.4), that for each of the drying zones (3.1, 3.2, 3.3, 3.4) an amount and/or a temperature of the circulating air are regulated so that the maximum temperature of the paper web (1) is 99° C., and that exhaust air is extracted from a first one of the drying zones (3.1, 3.2, 3.3, 3.

Abstract: Optical radiation sources functioning on different optical bands radiate on different optical bands and focus optical radiation on a region in a web surface as pulses in such a manner that illumination areas of the pulses overlap on the plane of the web. At most one optical radiation band is focused on the web from the direction of the normal. The spatial intensity distribution of at least one optical band differs from the uniform distribution and the intensity distributions of at least two different optical bands differ from one another in a predetermined manner. A camera forms still images of the web surface region on each optical radiation band. An image-processing unit determines the surface topography of the web on the basis of the images. In addition, a controller may control the paper manufacturing process on the basis of the determined surface topography.

Abstract: A pulp pre-processor for the papermaking industry uses pulp fiber analyzers to determine the distribution of fiber parameters, such as length, curl or coarseness from a feed source, such as recycled pulp, and mixes metered portions of pulp from augmenting pulp sources on an as-needed basis to provide a uniform distribution of a particular fiber parameter while maximizing use of recycled pulp.

Abstract: A method includes steps of: expressing changes of velocity components of a paper material at an exit of a slice lip by using a mathematical model, wherein the changes of velocity components are caused by manipulating an edge flow adjustment means (or a side bleed adjustment means) of a headbox when supplying the paper material on a wire; without changing a velocity component of a flow of the paper material in the mathematical model, setting the mathematical model based on an assumption in which a velocity component orthogonally crossing a flow direction of the paper material is proportionally changed by changes of an edge flow (or a side bleed) of a certain response width from the exit of the slice lip; and conducting a forecasting calculation of changes of a fiber orientation profile in a cross direction by using the mathematical model.

Abstract: Apparatus and methods for controlling the flow of a pulp suspension from a container in which the pulp is processed or stored are disclosed. The container is pressurized to a first pressure and includes an outlet for the pulp suspension, a pump includes an inlet and an outlet, and the pump inlet is connected to the container. The pulp suspension is fed from the inlet to the outlet of the pump and provides a controlled decrease in pressure to which the pulp suspension is subjected in the pump during such transport, and the flow from the container is controlled by adjusting this controlled decrease in pressure.

Abstract: A papermaking raw material processor capable of reforming pulp in papermaking a process using cavitation includes a first pump 5 jets jet liquid and second pump 6 jets suspension containing; e.g., pulp fibers into a processing unit inside which cavitation is generated by generation of a jet stream. Inside processing unit 2, a jet stream generates cavitation to carry out a reforming processing in which ink, or the like, is removed from the fibers by a blast resulting from collapse of cavitation bubbles generated there. The liquid after reforming processing is returned to second tank 4, except for a part of it fed to downstream steps, while the suspension is processed, as circulated between processing unit 2 and second tank 6.

Abstract: An apparatus for determining fiber orientation parameters of a sheet of material during a production process includes a polarized radiation generating system operable for providing polarized radiation having a frequency of at least 1×108 Hz. The radiation is aligned to be incident on a sheet material to be characterized. A polarimeter is aligned to receive the radiation transmitted by the sheet material. A photodetector is provided for measuring radiation received after polarization processing by the polarimeter. A processor is coupled to the photodetector for calculating Stokes parameters of the sheet material based upon intensities of the radiation received and determines at least one parameter relating to fiber orientation of the sheet material based upon the Stokes parameters.

Abstract: A method includes identifying first data associated with cyclic voltammetry measurements of a material being examined. The cyclic voltammetry measurements include applying a varying first voltage to the material and measuring a first current. The method also includes identifying second data associated with impedance measurements. The impedance measurements include applying a second voltage to the material and measuring a second current. The second data includes a scaling factor. The method further includes adjusting at least part of the first data using the scaling factor and identifying a composition of the material using the adjusted first data. The first data could include a current versus voltage curve that associates values of the first current to values of a sweep voltage. The first data could be adjusted by normalizing the curve using the scaling factor, and the normalized curve could be used to generate a current derivative curve.

Abstract: Method and device for producing a web of tissue. In the method, the web of tissue is led over at least one drying cylinder, doctored off the latter with a creping doctor and then wound up by way of a winding device. The web of tissue is supported at least largely over the entire distance between creping doctor and winding device on one side by a transfer device, so that there is only a short free web draw, while its other side is free. The device includes at least one drying cylinder, a creping doctor arranged on the drying cylinder and a winding device that winds up the web of tissue. Between the creping doctor and the winding device, a transfer device at least largely bridges the entire distance which supports the web of tissue on one side. There is a short free web draw, but its other side is left free.

Abstract: A method includes receiving a measurement associated with an anisotropy of a first surface and a measurement associated with an anisotropy of a second surface of a sheet of material. The method also includes adjusting an operating parameter associated with a headbox based on the measurements. The headbox is associated with manufacture of the sheet. The operating parameter could include a jet speed, a jet impingement angle, a jet thickness, a slice opening, and/or a slice apron projection. Adjusting the operating parameter could be based on a difference between a measured anisotropy of the first surface and a measured anisotropy of the second surface. For example, the operating parameter could be adjusted to achieve a desired difference between the measured anisotropy of the first surface and the measured anisotropy of the second surface. Multiple headboxes could be controlled, such as when different headboxes are used to produce different layers of a multi-layer sheet.

Abstract: Apparatus and methods for controlling the flow of a pulp suspension from a container in which the pulp is processed or stored are disclosed. The container is pressurized to a first pressure and includes an outlet for the pulp suspension, a pump includes an inlet and an outlet, and the pump inlet is connected to the container. The pulp suspension is fed from the inlet to the outlet of the pump and provides a controlled decrease in pressure to which the pulp suspension is subjected in the pump during such transport, and the flow from the container is controlled by adjusting this controlled decrease in pressure.

Abstract: The invention relates to a method for optimizing the energy balance of a forming section in a machine for producing fibrous webs, in which a fiber suspension, which is fed to the forming section by way of a material ramp after the immobility point is reached, is passed through at least two dewatering units within a compression zone and to a subsequent functional unit. The invention is characterized in that a setpoint value for a target dryness to be set is predefined based on the existing dewatering elements as a function of a theoretical maximum achievable dryness under plant conditions in the area of the transition zone, said setpoint being selected such that it is less than the theoretical maximum achievable dryness but is equal to or greater than a required minimum dryness in the area of the transition zone, and that the target dryness is controlled by lowering the inlet dryness at one of the last dewatering units disposed in the direction of passage of the fiber suspension within the compression zone.

Abstract: Optical radiation sources functioning on different optical bands radiate on different optical bands and focus optical radiation on a region in a web surface as pulses in such a manner that illumination areas of the pulses overlap on the plane of the web. At most one optical radiation band is focused on the web from the direction of the normal. The spatial intensity distribution of at least one optical band differs from the uniform distribution and the intensity distributions of at least two different optical bands differ from one another in a predetermined manner. A camera forms still images of the web surface region on each optical radiation band. An image-processing unit determines the surface topography of the web on the basis of the images. In addition, a controller may control the paper manufacturing process on the basis of the determined surface topography.

Abstract: In a used paper recycling apparatus of furniture size that can be installed in a small shop or room, this is a belt meandering preventive device of a simple structure for executing the paper making process for manufacturing used paper pulp at low trouble rate and high reliability. A rolling roller rolls on a mesh belt of a paper making net conveyor unit for processing and conveying used paper pulp while applying a tension a, roller oscillating unit oscillates this rolling roller in a direction intersecting with the running direction of the mesh belt, and the rolling roller is maintained at the neutral position so as to be perpendicular to the running direction of the mesh belt when the running position of the mesh belt is in an appropriate running range, and the rolling roller is directed to a meandering correcting direction for moving the running position of the mesh belt into the appropriate running range when the running position of the mesh belt is out of the appropriate running range.

Abstract: Methods for processing pulp in an apparatus for washing and dewatering pulp and a system for controlling this apparatus are provided. The apparatus includes a pair of rotatable press rolls installed in vats and including a press nip therebetween, an inlet for feeding the pulp to the press nip, with one of the press rolls being movable in relation to the other and in which the processing of the pulp is determined by the number of variable operating parameters. The method includes utilizing the distance between the press rolls as a variable operating parameter, setting a desired value for a specific control parameter, measuring the specific control parameter, and adjusting at least two of the variable operating parameters during operation to maintain the difference between the desired value and the measured value of the specific control parameter below a predetermined difference. Systems for controlling this apparatus are also disclosed.

Abstract: A method includes steps of: expressing changes of velocity components of a paper material at an exit of a slice lip by using a mathematical model, wherein the changes of velocity components are caused by manipulating an edge flow adjustment means (or a side bleed adjustment means) of a headbox when supplying the paper material on a wire; without changing a velocity component of a flow of the paper material in the mathematical model, setting the mathematical model based on an assumption in which a velocity component orthogonally crossing a flow direction of the paper material is proportionally changed by changes of an edge flow (or a side bleed) of a certain response width from the exit of the slice lip; and conducting a forecasting calculation of changes of a fiber orientation profile in a cross direction by using the mathematical model.

Abstract: This invention relates to a method and system for detecting contamination of boiler condensate and/or boiler feedwater in a papermaking process. The method includes measuring an oxidation-reduction potential at one or more locations in the boiler condensate and/or the boiler feedwater of the papermaking process with one or more corrosion stress monitoring devices. A controller is operable to assess whether the measured or a calculated oxidation-reduction potential is within an optimum range. The controller is operable to cause transmission of a signal to direct feeding an effective amount of one or more reductants and/or one or more pH-controlling chemicals into the boiler feedwater and/or one or more a satellite feed locations of the papermaking process.

Abstract: A method of and an apparatus for controlling the height of a material column in a vessel upstream of a pump, in which method material is conveyed into an upper portion of the vessel, electrical signals are provided on the basis of the presence of material at predetermined measuring levels of the vessel by using a first sensor set disposed at a first measuring level at the upper portion of the vessel and a second sensor set disposed at a second measuring level at the lower portion of the vessel, and material is extracted at a controlled flow speed from a lower portion of the vessel by the pump, wherein the provided electrical signals are used to infer weighting factors of measuring level presence functions, and the flow speed is controlled on the basis of the weighting factors of the measuring level presence functions.

Abstract: Washing apparatus as well as methods for washing and dewatering a cellulose pulp are disclosed comprising a rotary drum with outer compartments for pulp washing, and a stationary casing surrounding the drum to define an annular space between the casing and the drum which is divided into zones by longitudinal seals. The function of the seals is optimized by a force measurement device for measuring forces acting on the longitudinal seal for measuring a biasing force of a spring package in the measurement device and for measurement of a force acting on a load transmission shaft of the device as well as an extractor for extracting a force acting against the seal in a direction away from the drum.

Abstract: Pulp processing equipment used to produce high-quality recycled pulp with little damage to fibers, high brightness and low residual ink by means of a force selectively acting on fiber surfaces during the process of recycling waste paper is disclosed. Moreover, fiber surfaces are modified by means of a force acting on only the fiber surfaces to obtain high-quality pulp and to render harmless dirts deteriorating pulp quality. A jet system is provided having one or more nozzles for jetting an aqueous slurry containing a material comprising cellulose into a vessel.